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K. Baranitharan, Dineshbabu V., Robert Concepción-Lázaro, Balamanigandan R., K. Selvakumarasamy, Mahaveerakannan R., and Mohammed Wasim Bhatt
- Healthcare Analytics, Vol 3, Iss , Pp 100184- (2023)
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Collaborative and adaptive cyber Défense strategies, Healthcare networks, Cyber security edge computing, Cyber Défense strategies, Internet of Things, Computer applications to medicine. Medical informatics, and R858-859.7
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The Internet of Things (IoT) is a massive network connecting various devices and computer systems. This technology makes prototyping and distributing cutting-edge software and services easier. Through specifically created healthcare networks, the IoT makes it simple to link digital and tangible devices. Disputes continue to arise in the industry due to the absence of uniformity and the rapid growth of products, services, and methods. This study seeks to provide a birds-eye perspective of the technologies and protocols that support the IoT’s foundation. We start by introducing an elaborate process to examine the function of healthcare networks in creating and disseminating IoT-based software and some solutions to the current problems. We then discuss and formulate future challenges and the unanswered concerns surrounding the IoT’s support for healthcare networks. The primary focus of this research is to dissect the IoT, or horizontal network, into its constituent parts. These elements are essential for creating secure and robust mobile applications.
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2. Technologies for implementing of artificial intelligence as a service based on hardware accelerators [2023]
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Artem Perepelitsyn, Yelyzaveta Kasapien, Herman Fesenko, and Vyacheslav Kharchenko
- Авіаційно-космічна техніка та технологія, Vol 0, Iss 6, Pp 57-65 (2023)
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штучний інтелект, fpga, ші як сервіс, гетерогенні проєкти ші систем, апаратні прискорювачі ші, dpu, інструментальні засоби розробки ші, xrt, Motor vehicles. Aeronautics. Astronautics, and TL1-4050
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The subject of study in this article is modern technologies, tools and methods of building AI systems as a service using FPGA as a platform. The goal is to analyze modern technologies and tools used to develop FPGA-based projects for systems that implement artificial intelligence as a service and to prepare a practical AI service prototype. Task: to analyze the evolution of changes in the products of leading manufacturers of programmable logic devices and experimental and practical examples of the implementation of the paradigm of continuous reprogramming of programmable logic; analyze the dynamics of changes in the development environment of programmable logic systems for AI; analyze the essential elements of building projects for AI systems using programmable logic. According to the tasks, the following results were obtained. The area of application of hardware implementation of artificial intelligence for on-board and embedded systems including airspace industry, smart cars and medical systems is analyzed. The process of programming FPGA accelerators for AI projects is analyzed. The analysis of the capabilities of FPGA with HBM for building projects that require enough of high speed memory is performed. Description languages, frameworks, the hierarchy of tools for building of hardware accelerators for AI projects are analyzed in detail. The stages of prototyping of AI projects using new FPGA development tools and basic DPU blocks are analyzed. The parameters of the DPU blocks were analyzed. Practical steps for building such systems are offered. The practical recommendations for optimizing the neural network for FPGA implementation are given. The stages of neural network optimization are provided. The proposed steps include pruning of branches with low priority and the use of fixed point computations with custom range based on the requirements of an exact neural network. Based on these solutions, a practical case of AI service was prepared, trained and tested. Conclusions. The main contribution of this study is that, based on the proposed ideas and solutions, the next steps to create heterogeneous systems based on the combination of three elements are clear: AI as a service, FPGA accelerators as a technology for improving performance, reliability and security, and cloud or Edge resources to create FPGA infrastructure and AI as service. The development of this methodological and technological basis is the direction of further R&D.
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Marco Coco
- Applications in Engineering Science, Vol 15, Iss , Pp 100135- (2023)
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Phonon anisotropy, Heating effects, Temperature definition, Graphene, Monte Carlo method, Boltzmann equations, Engineering (General). Civil engineering (General), and TA1-2040
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The effect of inclusion of the planar phonon anisotropy on thermo-electrical behavior of graphene is analyzed. Charge transport is simulated by means of Direct Simulation Monte Carlo technique coupled with numerical solution of the phonon Boltzmann equations based on deterministic methods.The definition of the crystal lattice local equilibrium temperature is investigated as well and the results furnish possible alternative approaches to identify it starting from measurements of electric current density, with relevant experimental advantages, which could help to overcome the present difficulties regarding thermal investigation of graphene.Positive implications are expected for many applications, as the field of electronic devices, which needs a coherent tool for simulation of charge and hot phonon transport; the correct definition of the local equilibrium temperature is in turn fundamental for the study, design and prototyping of cooling mechanisms for graphene-based devices.
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Harsh G. Bhundiya and Zachary C. Cordero
- Additive Manufacturing Letters, Vol 6, Iss , Pp 100146- (2023)
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Wireframe structures, Path planning, Additive manufacturing, Deformation processing, Industrial engineering. Management engineering, and T55.4-60.8
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This paper presents a computer numerical control (CNC) deformation process, termed Bend-Forming, for fabricating 3D wireframe structures. The process relies on the combination of CNC wire bending with mechanical joints to construct reticulated structures from wire feedstock. A key component of the process is a path planning framework which uses Euler paths and geometrical computations to derive fabrication instructions for arbitrary 3D wireframe geometries. We demonstrate the process by fabricating exemplary structures on the order of 1 m, including reticulated columns, shells, and trusses, with rapid build times compared to other additive manufacturing techniques. The structures fabricated herein contain defects which result in residual stress and imperfect geometries. To determine the tolerances needed to fabricate accurate structures, we develop a model of error stack-up for Bend-Forming, using fabrication defects in feed length, bend and rotate angle, and strut curvature. We find that for tetrahedral trusses fabricated with Bend-Forming, defects in feed length and strut curvature have a large effect on the surface precision and stiffness of the truss, respectively, and are thus important tolerances to control to achieve structural performance metrics. Overall, Bend-Forming is a versatile and low-power process that is well suited for a wide-range of applications, from rapid prototyping of wireframe structures to in-space manufacturing.
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Noah Sargent, Yuankang Wang, Daozheng Li, Yunhao Zhao, Xin Wang, and Wei Xiong
- Additive Manufacturing Letters, Vol 6, Iss , Pp 100133- (2023)
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Directed energy deposition, entropy, grain refinement, alloy design, Industrial engineering. Management engineering, and T55.4-60.8
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Additive manufacturing (AM) is a tool for rapid prototyping with complex geometry. However, the cyclic heating and cooling in laser melting processes often cause large columnar grains that dominate the as-printed microstructure, resulting in a strong texture and anisotropic properties that limit the application of AM. In this work, we apply powder-based directed energy deposition to discover new alloys using mixtures of Inconel 718 (IN718) and Stainless Steel 316L (SS316L). We discovered that the 77 wt.% IN718 alloy mixture, with the highest configurational entropy, demonstrated an intriguingly fine grain structure in the as-built condition and after homogenization at 1180°C. Residual stress from the laser melting process was identified as the primary cause of the observed grain refinement phenomenon. Although, a quantitative analysis of the changes in grain size after homogenization in the alloy mixtures of IN718 and SS316L requires further research. The discovery of this unique microstructural behavior shows how in-situ mixing of commercially available powders can be used to develop next-generation feedstock materials for AM and improve the understanding of fundamental process-microstructure-property relationships.
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Chunxu Li, Fengbo Sun, Jingjing Tian, Jiahao Li, Haidan Sun, Yong Zhang, Shigong Guo, Yuanhua Lin, Xiaodan Sun, and Yu Zhao
- Bioactive Materials, Vol 24, Iss , Pp 361-375 (2023)
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3D printing, Zinc submicron particles, Osteoinductivity, Anti-inflammatory, Bone defect repair, Materials of engineering and construction. Mechanics of materials, TA401-492, Biology (General), and QH301-705.5
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Long-term nonunion of bone defects has always been a major problem in orthopedic treatment. Artificial bone graft materials such as Poly (lactic-co-glycolic acid)/β-tricalcium phosphate (PLGA/β-TCP) scaffolds are expected to solve this problem due to their suitable degradation rate and good osteoconductivity. However, insufficient mechanical properties, lack of osteoinductivity and infections after implanted limit its large-scale clinical application. Hence, we proposed a novel bone repair bioscaffold by adding zinc submicron particles to PLGA/β-TCP using low temperature rapid prototyping 3D printing technology. We first screened the scaffolds with 1 wt% Zn that had good biocompatibility and could stably release a safe dose of zinc ions within 16 weeks to ensure long-term non-toxicity. As designed, the scaffold had a multi-level porous structure of biomimetic cancellous bone, and the Young's modulus (63.41 ± 1.89 MPa) and compressive strength (2.887 ± 0.025 MPa) of the scaffold were close to those of cancellous bone. In addition, after a series of in vitro and in vivo experiments, the scaffolds proved to have no adverse effects on the viability of BMSCs and promoted their adhesion and osteogenic differentiation, as well as exhibiting higher osteogenic and anti-inflammatory properties than PLGA/β-TCP scaffold without zinc particles. We also found that this osteogenic and anti-inflammatory effect might be related to Wnt/β-catenin, P38 MAPK and NFkB pathways. This study lay a foundation for the follow-up study of bone regeneration mechanism of Zn-containing biomaterials. We envision that this scaffold may become a new strategy for clinical treatment of bone defects.
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Krithi Vishnu Balaji, Sumant Bhutoria, Sunita Nayak, PR Anil Kumar, and Shiny Velayudhan
- Biomedical Engineering Advances, Vol 5, Iss , Pp 100083- (2023)
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3D Bioprinting, Bioink, Printability, FDM, Carboxy methyl cellulose, Medical technology, and R855-855.5
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Three dimensional (3D) bioprinting is a rapid prototyping technology that can be used to accurately position living cells and biomaterials called bioink, to fabricate functional living tissue constructs or organs. The bioink are deposited in 3D in a layer-by-layer manner using a bioprinter. However, commercially available 3D bioprinters are expensive, limiting the widespread adoption of this technology in low-resource laboratories. To overcome this limitation the conventional Filament Deposition Modelling (FDM) 3D printer can be modified to a 3D bioprinter by replacing the print head unit. During the makeover, The device has to perform in its most efficient capacity in synergy with the bioink used. Hence it is essential to check the bio-printabililty of bioink in the modified FDM printer. In this study we created certain specific G-codes for the evaluation of hybrid bioinks and authenticated the printability. This study focuses on quantifying the printability of a hybrid hydrogel composed of sodium salt carboxymethyl cellulose (CMC) and gelatin using a 3D bioprinter based on the RepRap prototyper. The 3D design and slicing parameters were generated using opensource software and manually edited for printability evaluation. The results of these experiments indicate the importance of printability evaluation of custom bioprinters and provide some key aspects of how to modify CAD design parameters for printability evaluation. This approach can also be adopted to evaluate the printability of other hydrogels for bio-printing. The codes are created to evaluate the printability of bioink using FDM modified bioprinters. The printability evaluation is limited to high viscous bioink for extrusion bioprinting. A user friendly, simple G-Codes and methodology for evaluation of printability of bioink using FDM modified bioprinters. To authors knowledge, this is the first report on 3D printability evaluation of bioink using FDM modified bioprinters. The study also fulfills an identified need to study printability of bioink in biofabrication by additive manufacturing.
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Tommaso Caldognetto, Andrea Petucco, Andrea Lauri, and Paolo Mattavelli
- HardwareX, Vol 14, Iss , Pp e00411- (2023)
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Power electronics, Inverters, Rapid control prototyping, Experimental setups, Science (General), and Q1-390
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A flexible power electronic converter embedding a rapid control prototyping platform suitable to be applied in research test setups and teaching laboratories is proposed and described in this paper. The electronic system is composed of three subsystems, namely, i) three half-bridge power boards, ii) a dc-link capacitor bank with a half-bridge power module for active dc-link control, iii) an interfacing board, called motherboard, to couple the power modules with a control unit, iv) a digital control unit with rapid control prototyping functionalities for controlling power electronic circuits. Power modules integrate sensors with related conditioning circuits, driving circuits for power switches, and protection circuits. Conversion circuits exploit GaN electronic switches for optimal performance. The architecture and implementation of the system are described in detail in this manuscript. Main applications are in the implementation of conversion circuits for supplying arbitrary ac or dc voltages or currents, testing of new control algorithms for power electronic converters, testing of systems of electronic converters in, for example, smart nanogrids or renewable energy applications, training of undergraduate and graduate students.
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9. Single-step fabrication of superhydrophobic surfaces by two-photon polymerization micro 3D printing [2023]
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Ada-Ioana Bunea, Nina Szczotka, Jesper Navne, and Rafael Taboryski
- Micro and Nano Engineering, Vol 19, Iss , Pp 100192- (2023)
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Superhydrophobic, Reentrant structures, Wenzel state, Cassie-Baxter state, Two-photon polymerization, 3D printing, Electronics, TK7800-8360, Technology (General), and T1-995
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In this work, we fabricate a hexagonal array of pillars where each pillar has a “micro-hoodoo” shape, i.e., a reentrant cross section. The shape of the pillars makes them more resilient towards total wetting, i.e., transition from a Cassie-Baxter non-wetting state to a Wenzel wetting state. We show the single-step fabrication of 4 × 4 mm2 arrays by two-photon polymerization direct laser writing of the polydimethylsiloxane (PDMS)-derived commercial resin IP-PDMS. The use of a hydrophobic resin for rapid prototyping of reentrant structures enables the fabrication of surfaces patterns displaying superhydrophobic behavior despite the use of relatively simple structures, i.e. with a single reentrant surface. By changing the size of the micro-hoodoos and the packing density of the arrays, we map wetting behaviors ranging from the pinning of water droplets in Wenzel state to non-wetting Cassie-Baxter states. The measured contact angles follow quite well the theoretical results obtained by minimizing Gibbs free energy using the Wenzel, Cassie-Baxter and partial wetting theories. Among the tested micropatterns, five exhibited superhydrophobic properties, with a static contact angle with water as high as 158.1° ± 7.1°. This is the first demonstration of superhydrophobic surfaces produced by two-photon polymerization direct laser writing of PDMS in a single-step process.
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Marie Reischke, Oliver Vanderpoorten, and Florian Ströhl
- Micro and Nano Engineering, Vol 19, Iss , Pp 100186- (2023)
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Additive manufacturing, Two-photon, Direct laser writing, Photolithography, 3D microscopy, SU-8, Electronics, TK7800-8360, Technology (General), and T1-995
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Multifocus gratings (MFGs) enable microscopes and other imaging systems to record entire Z-stacks of images in a single camera exposure. The exact grating shape depends on microscope parameters like wavelength and magnification and defines the multiplexing onto a grid of MxN Z-slices. To facilitate the swift production and alteration of MFGs for a system and application at hand, we have developed a fabrication protocol that allows manufacturing of 1xN MFGs within hours and without the requirement of clean room facilities or hazardous etching steps. Our approach uses photolithography with a custom-built stage-scanning direct laser writing (DLW) system. By writing MFG grating lines into spin-coated negative tone SU-8 photoresist, polymerized parts are crafted onto the substrate and thus directly become a part of the grating structure. We provide software to generate the required MFG grating line paths, details of the DLW system and fully characterize a manufactured MFG. Our produced MFG is 5.4 mm in diameter and manages to record an image volume with a Z-span of over 600 μm without spherical aberrations or noticeable loss of resolution.
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Galík Ján, Varecha Daniel, Drbúl Mário, Madaj Rudolf, and Konstantová Viera
- Production Engineering Archives, Vol 29, Iss 2, Pp 201-215 (2023)
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pathogens, uv-c radiation, disinfection, additive manufacturing, rapid prototyping, Machine design and drawing, TJ227-240, Engineering machinery, tools, and implements, and TA213-215
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This manuscript aims to familiarise readers with the development of a device for the construction of a mobile disinfection chamber for small communication devices and small objects. The conceptual design and the material of the new device play essential roles in the design process of a new device. The manuscript presents concepts based primarily on previous experience and different perspectives. The concept design is created in the 3D modelling program CREO Parametric 8.0. A multi-criteria team evaluation determined the most suitable version of the idea. For dimensioning and shape adaptation of the device was used EinScan SP device (3D scanning method). The article's aim was also to establish a suitable way of producing a prototype using tribological research in available production methods and materials within rapid prototyping. Using the ALICONA Infinite Focus G5 device, experimentally investigated the parameters characterising the surface of the parts. The end of the manuscript focused on the mechanical structure and subjecting them to FEM analysis in the program ANSYS Workbench. The design of the concept disinfection device was also for extreme cases of use. Within this issue was optimising shapes, wall thicknesses, reinforcement design and other necessary modifications using the FEM analysis. From the results, the most suitable material to produce a more significant number of parts may not be the most suitable material to create prototype devices. Tools such as 3D scanning, rapid prototyping, and FEM analysis can "significantly" help reduce mistakes before testing the device.
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LI Qun xing
- 口腔疾病防治, Vol 31, Iss 6, Pp 381-388 (2023)
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jaw defect, functional reconstruction, digital technology, computer-aided design, 3d printing, personalized surgical instruments, preoperative virtual surgery, immediate implantation, and Medicine
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With the development of computer-aided surgery and rapid prototyping via 3D printing technology, digital surgery has rapidly advanced in clinical practice, especially in the field of oral and maxillofacial surgery. 3D printing technology has been applied to the functional restoration and reconstruction of the jawbone. Before surgery, a 3D digital model is constructed through software to plan the scope of the osteotomy, shape the bone graft and plan the placement of the implant. Additionally, 3D models of personalized surgical instrument guides are printed prior to surgery. With these 3D-printed models and guides, accurate excision of the jaw tumor, accurate placement of the grafted bone and precise placement of implants can be achieved during surgery. Postoperative evaluation of accuracy and function shows that 3D printing technology can aid in achieving the biomechanical goals of simultaneous implant placement in jaw reconstruction, and in combination with dental implant restoration, the technology can improve patients' postoperative occlusal and masticatory functions. Nevertheless, 3D printing technology still has limitations, such as time-consuming preparation before surgery. In the future, further development of 3D printing technology, optimization of surgical plans, and alternative biological materials are needed. Based on domestic and foreign literature and our research results, we have reviewed the process and clinical application prospects of jaw reconstruction via 3D printing technology to provide a reference for oral and maxillofacial surgeons.
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Ángel Antonio Rodríguez-Sevillano, María Jesús Casati-Calzada, Rafael Bardera-Mora, Javier Nieto-Centenero, Juan Carlos Matías-García, and Estela Barroso-Barderas
- Aerospace, Vol 10, Iss 467, p 467 (2023)
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morphing wings, micro air vehicles (MAVs), airfoil parameterization, CST (class-shape transformation), PythonOCC, Motor vehicles. Aeronautics. Astronautics, and TL1-4050
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This paper shows a series of tools that help in the research of morphing micro air vehicles (MAVs). These tools are aimed at generating parametric CAD models of wings in a few seconds that can be used in aerodynamic studies, either via CFD directly using the model obtained or via wind tunnel through rapid prototyping with 3D printers. It also facilitates the analysis of morphing wings by allowing for the continuous parametric deformation of the airfoils and the wing geometry. In addition, one of the tools greatly simplifies the purely experimental design of this type of vehicle, allowing the transfer of experimental measurements to the computer, generating virtual models with the same deformation as the physical model. This software has two fundamental parts. The first one is the parameterization of the airfoils, for which the CST (Class-Shape Transformation) method will be used. CST coefficients can be modified according to the actuator variable that changes the wing geometry. The second part is the generation of a three-dimensional parametric model of the wing. We used OpenCASCADE technology in its Python version called PythonOCC, which enables the generation of geometries with good surface quality for typical and non-standard wing shapes. Finally, the use of this software for the study of a morphing aircraft will be shown, as well as improvements that could be incorporated in the future to increase its capabilities for the design and analysis of MAVs.
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Boban Sudarevic, Joel Troya, Karl-Hermann Fuchs, Alexander Hann, Andras Vereczkei, and Alexander Meining
- Applied Sciences, Vol 13, Iss 5656, p 5656 (2023)
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endoscopy, endoscopic intervention, 3D printing, endoscopic instruments, minimally invasive surgery, rapid prototyping, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
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(1) Background: Interventional endoscopic procedures are growing more popular, requiring innovative instruments and novel techniques. Three-dimensional printing has demonstrated great potential for the rapid development of prototypes that can be used for the early assessment of various concepts. In this work, we present the development of a flexible endoscopic instrument and explore its potential benefits. (2) Methods: The properties of the instrument, such as its maneuverability, flexibility, and bending force, were evaluated in a series of bench tests. Additionally, the effectiveness of the instrument was evaluated in an ex vivo porcine model by medical experts, who graded its properties and performance. Furthermore, the time necessary to complete various interventional endoscopic tasks was recorded. (3) Results: The instrument achieved bending angles of ±216° while achieving a bending force of 7.85 (±0.53) Newtons. The time needed to reach the operating region was 120 s median, while it took 70 s median to insert an object in a cavity. Furthermore, it took 220 s median to insert the instrument and remove an object from the cavity. (4) Conclusions: This study presents the development of a flexible endoscopic instrument using three-dimensional printing technology and its evaluation. The instrument demonstrated high bending angles and forces, and superior properties compared to the current state of the art. Furthermore, it was able to complete various interventional endoscopic tasks in minimal time, thus potentially leading to the improved safety and effectiveness of interventional endoscopic procedures in the future.
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Yanjing Bi, Chao Li, Yannick Benezeth, and Fan Yang
- Applied Sciences, Vol 13, Iss 5835, p 5835 (2023)
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computer-assisted pronunciation training, high-level synthesis, embedded designs, machine learning, FPGA, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
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Computer-assisted pronunciation training (CAPT) is a helpful method for self-directed or long-distance foreign language learning. It greatly benefits from the progress, and of acoustic signal processing and artificial intelligence techniques. However, in real-life applications, embedded solutions are usually desired. This paper conceives a register-transfer level (RTL) core to facilitate the pronunciation diagnostic tasks by suppressing the mulitcollinearity of the speech waveforms. A recently proposed heterogeneous machine learning framework is selected as the French phoneme pronunciation diagnostic algorithm. This RTL core is implemented and optimized within a very-high-level synthesis method for fast prototyping. An original French phoneme data set containing 4830 samples is used for the evaluation experiments. The experiment results demonstrate that the proposed implementation reduces the diagnostic error rate by 0.79–1.33% compared to the state-of-the-art and achieves a speedup of 10.89× relative to its CPU implementation at the same abstract level of programming languages.
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Alessia Romani, Stefan Caba, Raffaella Suriano, and Marinella Levi
- Applied Sciences, Vol 13, Iss 5848, p 5848 (2023)
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polymer–matrix composites (PMCs), circular economy, recycled fibers reinforced polymers (FRPs), indirect 3D printing, Direct Ink Writing, liquid deposition modeling, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
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This work explores the use of additive manufacturing (AM) to reprocess recycled glass and carbon fibers in the automotive sector. It aims to foster exploitation of recycled Glass Fiber Reinforced Polymers (rGFRPs) and recycled Carbon Fiber Reinforced Polymers (rCFRPs) through two manufacturing workflows: indirect Fused Filament Fabrication (FFF) and UV-assisted Direct Ink Writing (UV-DIW). An industrial case study on vehicle components has been considered by prototyping one real component. After the tensile tests, some molds were fabricated with a FFF 3D printer for the indirect 3D printing process to cast an epoxy-based thermosetting resin with rGFs and rCFs. The second technology consisted in fabricating the parts by hardening in-situ a photo- and thermal-curable thermosetting acrylic liquid resin with rGFs. These results validate the use of AM and recycled composites for applications in the automotive sector. These approaches may be implemented for customizable components for batches below 100 vehicles as the first step for their exploitation.
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17. Optimizing the Auxiliary Air Channels of a Vortex Atomizer by 3D Printing Using the Taguchi Method [2023]
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Jung-Shun Chen and Shang-Rong Li
- Applied Sciences, Vol 13, Iss 5898, p 5898 (2023)
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atomizer, auxiliary air holes, 3D printing, Taguchi method, CFD, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
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In this study, the optimum spraying performance of a pressurized vortex atomizer using water as the working fluid was investigated experimentally by modifying the geometry of auxiliary air holes via the Taguchi method. The experimental results were also examined by CFD simulations. The four control factors of the auxiliary air holes are their numbers, areas, inclination angles, and lengths. With five levels for each control factor, an L25 orthogonal table was selected. Each case of the L25 orthogonal table was test repeatedly three times to obtain key average results. The auxiliary air holes were designed by a KISSlicer CAD tool and fabricated by 3D printing. The 3D printing was carried out by fused deposition of PLA with a resolution of about 30 μm. In the experiments, the spraying jet patterns were recorded, and the water droplet weights were measured. By using the signal to noise ratios and the smaller-the-better quality characteristic, the effect of the control factors of the auxiliary air holes in descending order is the numbers, areas, inclination angles, and hole lengths, respectively. The optimum air hole configuration is the one with six holes, an inclination angle of 20°, an area of 18 mm2, and a length of 8 mm. The optimum condition was confirmed by a signal to noise ratio of 20.5 dB with 95% confidence interval. The resulting smaller jet opening angle is about 42°, close to the simulated angle of 45°. That is, by the novelty of combining 3D printing with the Taguchi method, this study obtains the optimum design with fast prototyping and relatively few experiments.
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Tiancong Zhao, Huichao Zhu, and Hangyu Zhang
- Biosensors, Vol 13, Iss 546, p 546 (2023)
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laser-induced graphene, flexible pressure sensor, double-sided engraving, porous electrode, capacitive, Biotechnology, and TP248.13-248.65
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Flexible pressure sensors are widely applied in tactile perception, fingerprint recognition, medical monitoring, human–machine interfaces, and the Internet of Things. Among them, flexible capacitive pressure sensors have the advantages of low energy consumption, slight signal drift, and high response repeatability. However, current research on flexible capacitive pressure sensors focuses on optimizing the dielectric layer for improved sensitivity and pressure response range. Moreover, complicated and time-consuming fabrication methods are commonly applied to generate microstructure dielectric layers. Here, we propose a rapid and straightforward fabrication approach to prototyping flexible capacitive pressure sensors based on porous electrodes. Laser-induced graphene (LIG) is produced on both sides of the polyimide paper, resulting in paired compressible electrodes with 3D porous structures. When the elastic LIG electrodes are compressed, the effective electrode area, the relative distance between electrodes, and the dielectric property vary accordingly, thereby generating a sensitive pressure sensor in a relatively large working range (0–9.6 kPa). The sensitivity of the sensor is up to 7.71%/kPa−1, and it can detect pressure as small as 10 Pa. The simple and robust structure allows the sensor to produce quick and repeatable responses. Our pressure sensor exhibits broad potential in practical applications in health monitoring, given its outstanding comprehensive performance combined with its simple and quick fabrication method.
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Jimmi Normann Kristiansen, Catarina Batista, and Tuuli Maria Utriainen
- CERN IdeaSquare Journal of Experimental Innovation, Vol 7, Iss 1 (2023)
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editorial, Impact Innovation, Technology (General), T1-995, Technological innovations. Automation, and HD45-45.2
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This special issue presents 4 selected papers that have an emphasis on either the antecedents or provide concrete cases of impact innovation. Across the papers, the authors approach the topic of impact innovation from distinct angles, from measures of personal innovativeness to the power of physical teamwork, to the purpose of prototyping and entrepreneurial attitudes. This serves to demonstrate that innovation is not a linear process but rather a complex phenomenon that can be studied from a multitude of technical and social perspectives.
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Karla Mariana Rojas-Martínez, Pleuntje Brons, and Alexandru Dumitriu
- CERN IdeaSquare Journal of Experimental Innovation, Vol 7, Iss 1 (2023)
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Prototyping, low-fidelity prototype, high-fidelity prototype, Design Thinking, Perceived customer value, Technology (General), T1-995, Technological innovations. Automation, and HD45-45.2
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Perceived customer value is the measure of how customers perceive the total worth of a product or service. Providing a high perceived value is crucial for businesses to gain a competitive edge over their rivals and ensure long-term success. Prototyping has been shown to be able to measure perceived customer value and effectively collect user feedback early in the process before significant investments are made. However, the effects of prototype fidelity on assessing perceived customer value are yet to be explored. Nevertheless, the fidelity levels of a prototype should be accounted for since they significantly alter the prototype's complexity, appearance, and functionality. This paper explores such effects using a low- and a high-fidelity prototype applied to dentistry. The paper used qualitative and quantitative methods to gather feedback from dental healthcare experts and patients. Our study suggests that both low-and-high fidelity prototypes are suitable for assessing customer value. Furthermore, the fidelity levels complemented each other, improving the overall user feedback.
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21. 3D-Printed Hydrodynamic Focusing Lab-on-a-Chip Device for Impedance Flow Particle Analysis [2023]
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Dayananda Desagani, Shani Kleiman, Teddy Zagardan, and Hadar Ben-Yoav
- Chemosensors, Vol 11, Iss 283, p 283 (2023)
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lab-on-a-chip, 3D printing, point-of-care detection, electrochemical impedance spectroscopy, microfluidics, rapid prototyping, Biochemistry, and QD415-436
- Abstract
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Particles analysis, such as cell counting and differentiation, are widely used for the diagnosis and monitoring of several medical conditions, such as during inflammation. Three-dimensional-printed lab-on-a-chip (LOC) devices, which can utilize one of the cell counting methods, can bring this technology to remote locations through its cost-efficient advantages and easy handling. We present a three-dimensional-printed LOC device with integrated electrodes. To overcome the limited resolution of a 3D printer, we utilized a flow-focusing design. We modeled and simulated the mass transfer and flow dynamics in the LOC by incorporating a flow-focusing design and reached an optimal channel diameter of 0.5 mm, resulting in a flow-focusing distance of
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Cristian Deliv, Declan Devane, El Putnam, Patricia Healy, Amanda Hall, Sarah Rosenbaum, and Elaine Toomey
- Digital Health, Vol 9 (2023)
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Computer applications to medicine. Medical informatics and R858-859.7
- Abstract
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Objectives We aimed to develop a video animation knowledge translation (KT) resource to explain the purpose, use and importance of evidence synthesis to the public regarding healthcare decision-making. Methods We drew on a user-centred design approach to develop a spoken animated video (SAV) by conducting two cycles of idea generation, prototyping, user testing, analysis, and refinement. Six researchers identified the initial key messages of the SAV and informed the first draft of the storyboard and script. Seven members of the public provided input on this draft and the key messages through think-aloud interviews, which we used to develop an SAV prototype. Seven additional members of the public participated in think-aloud interviews while watching the video prototype. All members of the public also completed a questionnaire on perceived usefulness, desirability, clarity and credibility. We subsequently synthesised all data to develop the final SAV. Results Researchers identified the initial key messages as 1) the importance of evidence synthesis, 2) what an evidence synthesis is and 3) how evidence synthesis can impact healthcare decision-making. Members of the public rated the initial video prototype as 9/10 for usefulness, 8/10 for desirability, 8/10 for clarity and 9/10 for credibility. Using their guidance and feedback, we produced a three-and-a-half-minute video animation. The video was uploaded on YouTube, has since been translated into two languages, and viewed over 12,000 times to date. Conclusions Drawing on user-centred design methods provided a structured and transparent approach to the development of our SAV. Involving members of the public enhanced the credibility and usefulness of the resource. Future work could explore involving the public from the outset to identify key messages in developing KT resources explaining methodological topics. This study describes the systematic development of a KT resource with limited resources and provides transferrable learnings for others wishing to do similar.
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Marc Schmitt
- Intelligent Systems with Applications, Vol 18, Iss , Pp 200188- (2023)
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Artificial intelligence, Machine learning, AutoML, Business analytics, Data-driven decision making, Digital transformation, Cybernetics, Q300-390, Electronic computers. Computer science, and QA75.5-76.95
- Abstract
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The realization that AI-driven decision-making is indispensable in today's fast-paced and ultra-competitive marketplace has raised interest in industrial machine learning (ML) applications significantly. The current demand for analytics experts vastly exceeds the supply. One solution to this problem is to increase the user-friendliness of ML frameworks to make them more accessible for the non-expert. Automated machine learning (AutoML) is an attempt to solve the problem of expertise by providing fully automated off-the-shelf solutions for model choice and hyperparameter tuning. This paper analyzed the potential of AutoML for applications within business analytics, which could help to increase the adoption rate of ML across all industries. The H2O AutoML framework was benchmarked against a manually tuned stacked ML model on three real-world datasets. The manually tuned ML model could reach a performance advantage in all three case studies used in the experiment. Nevertheless, the H2O AutoML package proved to be quite potent. It is fast, easy to use, and delivers reliable results, which come close to a professionally tuned ML model. The H2O AutoML framework in its current capacity is a valuable tool to support fast prototyping with the potential to shorten development and deployment cycles. It can also bridge the existing gap between supply and demand for ML experts and is a big step towards automated decisions in business analytics. Finally, AutoML has the potential to foster human empowerment in a world that is rapidly becoming more automated and digital.
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24. Design of a Mobile App to Monitor and Control in Real Time Type 2 Diabetes Mellitus in Peru [2023]
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Lilian Ocares-Cunyarachi and Laberiano Andrade-Arenas
- International Journal of Interactive Mobile Technologies, Vol 17, Iss 10 (2023)
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Mobile Application, Covid-19, controlling, diabetes mellitus type 2, monitoring, Telecommunication, and TK5101-6720
- Abstract
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Diabetes in the world is a big problem. In addition, in Peru there are high cases of diabetes mellitus type 2, this happens due to insulin resistance, which causes damage to muscle, liver. In addition to the fact that the fat cells do not generate insulin correctly is because the body needs to generate more insulin so that glucose can enter the cells. Due to the problem that exists, a solution to the problem was sought with the objective of developing the design of a mobile application to monitor in real time, in such a way that it helps patients with diabetes to have a good monitoring plan. The methodology developed in the research is Design Thinking as it fits perfectly to the solution of the problems of society which was successfully developed using the phases of empathizing, defining, ideating, prototyping and finally testing. As a result, the design of the mobile application to monitor and control in real time patients with diabetes mellitus type 2 in Peru was obtained. In addition, obtained data on diabetes in Peru verified by the Ministry of Health, such as the results of registered cases of diabetes in Peru 2022, type of diabetes that develop in Peru on a large scale, type of diabetes in men and women. The complications that arise in the progression of the disease in addition to the cases of records according to sex and period of the year 2020 to 2022. Also, the cases presented diabetes throughout Peru therefore a survey was conducted where professors of the Universidad de Ciencias y Humanidades were conducted to qualify the prototypes for development which returned favorable results for implementation.
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Sarvesh Sonkar, Prashant Kumar, Yuvaraj Tanjore Puli, Riya Catherine George, Deepu Philip, and Ajoy Kanti Ghosh
- Journal of Aerospace Technology and Management, Vol 15 (2023)
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Hybrid, UAV, VTOL, BLDC, Fuselage, Aircraft design, Technology, Motor vehicles. Aeronautics. Astronautics, and TL1-4050
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Fixed-wing unmanned aerial vehicles (UAVs) offer the best aerodynamic efficiency required for long-distance or high-endurance applications, albeit their runway requirement for take-off and landing in comparison with quadcopters, helicopters, and flapping-wing UAVs that can perform vertical take-off and landing (VTOL). Integrating a multirotor system with a fixed-wing UAV imparts VTOL capabilities without significantly compromising fixed-wing aerodynamic efficiency, endurance, payload capacity or range. Documented system design approaches to address various challenges of such fusion processes are sparse. This research proposes a holistic approach for designing, prototyping, and testing an electric-powered fixed-wing hybrid VTOL UAV. The proposed system design approach augments the standard aircraft design process with additional steps to integrate VTOL capabilities. Separate fixed-wing and multirotor designs were derived from the frozen mission requirements, which were then fused. The process used simulation for modeling and evaluating alternatives for the hybrid UAV created using standard aircraft design equations. We prototyped and instrumented the final design to validate operational capabilities through test flights. Multiple flight trials identified the ideal combination of Lithium-Polymer (Li-Po) batteries for VTOL (8000mAh) and fixed-wing (14000mAh) modes to meet the endurance and range requirements. The redundant power supplies also increased the survivability chances of the hybrid UAV during failures.
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Arafat M Ibrahim, Ahmed M Ali, and Hisham Kamel
- Journal of Engineering and Applied Science, Vol 70, Iss 1, Pp 1-18 (2023)
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Finite element, Design optimization, Semi-trailer, Chassis prototyping, Experimental testing, Vehicle structure, Engineering (General). Civil engineering (General), and TA1-2040
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Abstract The automotive industry is placing a high priority on the design and optimization of articulated vehicles to minimize the risk of potential accidents or failures. Before mass production, field testing is a crucial step in the development process, requiring extensive dynamic tests to provide a secure design. However, these tests can be both expensive and time-consuming. This study presents the design process of a small-scale low-bed semi-trailer chassis, manufactured to simulate the structural response of an actual semi-trailer. The aim was to identify weak points through analysis under bending conditions and then optimize the thickness and width of the various cross-sections to increase strength while minimizing costs. After manufacturing and welding based on the optimized design, the equivalent chassis was subjected to two load cases for experimental testing. The test results confirmed the accuracy of the finite element analysis, with a deviation of 7.75 to 10.24% in stress levels compared to the numerical results. Overall, this study demonstrates an effective approach to optimize the design of low-bed semi-trailers for improved safety and cost-effectiveness.
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27. Development of e-module STEAM-Integrated problem based learning for salt hydrolysis topic [2023]
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Lusi Marvita Sari and Andromeda Andromeda
- Jurnal Pijar MIPA (Pengkajian Ilmu dan Pengajaran Matematika dan Ilmu Pengetahuan Alam), Vol 18, Iss 3, Pp 305-311 (2023)
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e-module, problem-based learning, steam, salt hydrolysis, plomp model, Science (General), Q1-390, Education (General), and L7-991
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Teaching materials as a support in the learning process in this technological era can be in the form of e-modules. Using e-modules in the learning process is declared effective, with a marked increase in student learning outcomes. This research aims to produce an integrated STEAM Problem-Based Learning E-Module of Salt Hydrolysis and determine its validity and practicality level. The type of research used is research development or Research and Development (R&D). The development model used is the Plomp model, which consists of 3 stages, namely: (1) Preliminary Research, (2) the Development or Prototyping Phase, and (3) Trial and Assessment (assessment phase). This research is limited to the development stage, namely the validity and practicality test. The research instrument used was a validity and practicality questionnaire. Five validators validated the e-module, while the practicality test was carried out by three chemistry teachers and 12 students in class XII MIPA senior high school SMAN 15 Padang. The results of the validation analysis obtained an average content validity test value of 0.87 with a valid category and an average media validity test value of 0.90 with a valid category. At the same time, the practicality tests of teachers and students obtained 91% and 91%, respectively, in the very practical practicality category. In conclusion, the salt hydrolysis e-module based on STEAM integrated Problem-Based Learning for class XI SMA/MA, which has been developed, is valid and practical.
- Full text View record in DOAJ
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Yeltika Afria Ningsih and Iswendi Iswendi
- Jurnal Pijar MIPA (Pengkajian Ilmu dan Pengajaran Matematika dan Ilmu Pengetahuan Alam), Vol 18, Iss 3, Pp 343-348 (2023)
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chemistry uno card game, periodic system of elements, plomp model, Science (General), Q1-390, Education (General), and L7-991
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This study aims to develop a chemical uno card game as a learning medium on the periodic system of elements for tenth-grade students and determine its validity and practicality. This type of research is research and development with the Plomp development model, which consists of three stages, namely (1) preliminary research, (2) prototyping stage, and (3) assessment phase. The research subjects were five chemistry lecturers at the Faculty of Mathematics and Natural Sciences, Padang State University, two chemistry teachers, and ten senior high school SMAN 13 Padang students for the 2022/2023 academic year. The research instrument was in the form of one-to-one evaluation interview sheets, media expert validity questionnaires, material expert validity questionnaires, and practicality test questionnaires. Validity data were analyzed using the Aiken'V formula, and practicality data were processed using the percentage formula. The validity value of the media expert was 0.88, and the material expert was 0.85 with the valid category. The results of the practicality analysis by teachers and students are in the very practical category, with respective values of 95.38% and 97%. In conclusion, the uno chemical card game as a learning medium in the periodic system of elements was valid and practical.
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29. Design a simple distillation project-based on chemical literacy on the topic of the alcohol phase F [2023]
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Meylinda Anggraini and Eka Yusmaita
- Jurnal Pijar MIPA (Pengkajian Ilmu dan Pengajaran Matematika dan Ilmu Pengetahuan Alam), Vol 18, Iss 3, Pp 386-391 (2023)
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Science (General), Q1-390, Education (General), and L7-991
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This study aims to design a simple distillation project on chemical literacy on alcohol phase f. This research was designed using the Plomp development model, which consists of 3 stages: the preliminary research stage, the development stage or prototyping, and the assessment stage. In this study, the authors limit the research to the development stage prototype, which produces prototype III. This project was designed using the project-based learning model with a combination of the anatomy of the project-based learning model) and project-based learning syntax, which contains aspects of chemical literacy. The development of this simple distillation project on chemical literacy on the topic of alcohol phase f is expected to assist teachers in overcoming obstacles in making learning media. It can be used as one of the learning media that can help students in learning, especially on alcohol. Testing the content validity and construct validity was carried out by five validators (Padang State University lectures and teachers of senior high school). The data obtained from the validator was then analyzed using Aiken’s V formula. The results of data analysis in this study showed that the average results of Aiken's V on content validity were 0.89, and construct validity was 0.90, which is included in the valid category.
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Ankita Gupta, Lakhwinder Kaur, and Gurmeet Kaur
- PeerJ Computer Science, Vol 9, p e1268 (2023)
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Wheat, Image processing, Machine learning, Chlorophyll fluoroscence, Drought, Texture analysis, Electronic computers. Computer science, and QA75.5-76.95
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The workflow of this research is based on numerous hypotheses involving the usage of pre-processing methods, wheat canopy segmentation methods, and whether the existing models from the past research can be adapted to classify wheat crop water stress. Hence, to construct an automation model for water stress detection, it was found that pre-processing operations known as total variation with L1 data fidelity term (TV-L1) denoising with a Primal-Dual algorithm and min-max contrast stretching are most useful. For wheat canopy segmentation curve fit based K-means algorithm (Cfit-kmeans) was also validated for the most accurate segmentation using intersection over union metric. For automated water stress detection, rapid prototyping of machine learning models revealed that there is a need only to explore nine models. After extensive grid search-based hyper-parameter tuning of machine learning algorithms and 10 K fold cross validation it was found that out of nine different machine algorithms tested, the random forest algorithm has the highest global diagnostic accuracy of 91.164% and is the most suitable for constructing water stress detection models.
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Chrysoula Pandelidi, Ryan Blakis, Kok Peng Marcian Lee, Stuart Bateman, Milan Brandt, and Mladenko Kajtaz
- Polymers, Vol 15, Iss 2395, p 2395 (2023)
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polyamide-11, thermal aging, mechanical performance, powder aging, powder bed fusion, additive manufacturing, Organic chemistry, and QD241-441
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The transition of additive manufacturing (AM) from a technique for rapid prototyping to one for manufacturing of near net or net components has been led by the development of methods that can repeatedly fabricate quality parts. High-speed laser sintering and the recently developed multi-jet fusion (MJF) processes have seen quick adoption from industry due to their ability to produce high-quality components relatively quickly. However, the recommended refresh ratios of new powder led to notable amounts of used powder being discarded. In this research, polyamide-11 powder, typically used in AM, was thermally aged to investigate its properties at extreme levels of reuse. The powder was exposed to 180 °C in air for up to 168 h and its chemical, morphological, thermal, rheological, and mechanical properties were examined. To decouple the thermo-oxidative aging phenomena from AM process related effects, such as porosity, rheological and mechanical properties characterisation was performed on compression-moulded specimens. It was found that exposure notably affected the properties of both the powder and the derived compression-moulded specimens within the first 24 h of exposure; however, consecutive exposure did not have a significant effect.
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Tarek Elouaret, Sylvain Colomer, Frédéric De Melo, Nicolas Cuperlier, Olivier Romain, Lounis Kessal, and Stéphane Zuckerman
- Sensors, Vol 23, Iss 4631, p 4631 (2023)
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FPGA, bio-inspired algorithms, Wizarde custom platform, Nvidia Jetson TX2, neural networks, N-LOC, Chemical technology, and TP1-1185
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Autonomous vehicles require efficient self-localisation mechanisms and cameras are the most common sensors due to their low cost and rich input. However, the computational intensity of visual localisation varies depending on the environment and requires real-time processing and energy-efficient decision-making. FPGAs provide a solution for prototyping and estimating such energy savings. We propose a distributed solution for implementing a large bio-inspired visual localisation model. The workflow includes (1) an image processing IP that provides pixel information for each visual landmark detected in each captured image, (2) an implementation of N-LOC, a bio-inspired neural architecture, on an FPGA board and (3) a distributed version of N-LOC with evaluation on a single FPGA and a design for use on a multi-FPGA platform. Comparisons with a pure software solution demonstrate that our hardware-based IP implementation yields up to 9× lower latency and 7× higher throughput (frames/second) while maintaining energy efficiency. Our system has a power footprint as low as 2.741 W for the whole system, which is up to 5.5–6× less than what Nvidia Jetson TX2 consumes on average. Our proposed solution offers a promising approach for implementing energy-efficient visual localisation models on FPGA platforms.
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Ruben Viegas, Friedrich Zabel, and Antonio Silva
- Sensors, Vol 23, Iss 4931, p 4931 (2023)
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spiral source, underwater acoustics, bearing angle estimate, spiral source calibration, underwater localization, Chemical technology, and TP1-1185
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Underwater acoustic spiral sources can generate spiral acoustic fields where the phase depends on the bearing angle. This allows estimating the bearing angle of a single hydrophone relative to a single source and implementing localization equipment, e.g., for target detection or unmanned underwater vehicle navigation, without requiring an array of hydrophones and/or projectors. A spiral acoustic source prototype made out of a single standard piezoceramic cylinder, which is able to generate both spiral and circular fields, is presented. This paper reports the prototyping process and the multi-frequency acoustic tests performed in a water tank where the spiral source was characterized in terms of the transmitting voltage response, phase, and horizontal and vertical directivity patterns. A receiving calibration method for the spiral source is proposed and showed a maximum angle error of 3° when the calibration and the operation were carried out in the same conditions and a mean angle error of up to 6° for frequencies above 25 kHz when the same conditions were not fulfilled.
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Angela Busato, Michaela Servi, Yary Volpe, Rocco Furferi, and Maurizio Scorianz
- SoftwareX, Vol 22, Iss , Pp 101398- (2023)
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Surgical planning, Rapid prototyping, Medical application, 3D manipulation, Computer software, and QA76.75-76.765
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This paper presents a collaborative platform developed to allow the communication between surgeons and engineers in the process of designing patient-specific surgical instruments. To date, only a few applications are available to collaboratively create surgical instruments from medical 3D models, mostly dedicated to expert CAD modelers. This makes the preoperative planning process time-consuming and inefficient limiting the usability of applications and making planning difficult and inaccurate. Accordingly, we propose a solution in the form of a web-based, interactive, extendable, 3D navigation and manipulation application, called Precise, which does not require client installation. Precise is a lightweight, high-performance application built to provide easy-to-use, powerful, on-demand visualization and manipulation of 3D images, implemented using open-source libraries.
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Andreas Frithioff, Kenneth Weiss, Martin Frendø, Pascal Senn, Peter Trier Mikkelsen, Daniel Sieber, Mads Sølvsten Sørensen, David Bue Pedersen, and Steven Arild Wuyts Andersen
- 3D Printing in Medicine, Vol 9, Iss 1, Pp 1-8 (2023)
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3D printing, Additive manufacturing, Rapid prototyping, Temporal bone, Mastoidectomy, Training, Medical physics. Medical radiology. Nuclear medicine, and R895-920
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Abstract Background 3D-printed temporal bone models can potentially provide a cost-effective alternative to cadaver surgery that can be manufactured locally at the training department. The objective of this study was to create a cost-effective 3D-printed model suitable for mastoidectomy training using entry level and commercially available print technologies, enabling individuals, without prior experience on 3D-printing, to manufacture their own models for basic temporal bone training. Methods Expert technical professionals and an experienced otosurgeon identified the best material for replicating the temporal bone and created a cost-effective printing routine for the model using entry-level print technologies. Eleven participants at a temporal bone dissection course evaluated the model using a questionnaire. Results The 3D-printed temporal bone model was printed using a material extrusion 3D-printer with a heat resistant filament, reducing melting during drilling. After printing, a few simple post-processing steps were designed to replicate the dura, sigmoid sinus and facial nerve. Modifying the 3D-printer by installing a direct-drive and ruby nozzle resulted in more successful prints and less need for maintenance. Upon evaluation by otorhinolaryngology trainees, unanimous feedback was that the model provided a good introduction to the mastoidectomy procedure, and supplementing practice to cadaveric temporal bones. Conclusion In-house production of a cost-effective 3D-printed model for temporal bone training is feasible and enables training institutions to manufacture their own models. Further, this work demonstrates the feasibility of creating new temporal bone models with anatomical variation to provide ample training opportunity.
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Avdhoot Walunj, Ying Chen, Yuyuan Tian, and Zhiwei Zeng
- Agronomy, Vol 13, Iss 1260, p 1260 (2023)
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DEM, soil–plant–machine interactions, soil dynamics, machinery systems, numerical modeling, and Agriculture
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The study of soil–plant–machine interaction (SPMI) examines the system dynamics at the interface of soil, machine, and plant materials, primarily consisting of soil–machine, soil–plant, and plant–machine interactions. A thorough understanding of the mechanisms and behaviors of SPMI systems is of paramount importance to optimal design and operation of high-performance agricultural machinery. The discrete element method (DEM) is a promising numerical method that can simulate dynamic behaviors of particle systems at micro levels of individual particles and at macro levels of bulk material. This paper presents a comprehensive review of the fundamental studies and applications of DEM in SPMI systems, which is of general interest to machinery systems and computational methods communities. Important concepts of DEM including working principles, calibration methods, and implementation are introduced first to help readers gain a basic understanding of the emerging numerical method. The fundamental aspects of DEM modeling including the study of contact model and model parameters are surveyed. An extensive review of the applications of DEM in tillage, seeding, planting, fertilizing, and harvesting operations is presented. Relevant methodologies used and major findings of the literature review are synthesized to serve as references for similar research. The future scope of coupling DEM with other computational methods and virtual rapid prototyping and their applications in agriculture is narrated. Finally, challenges such as computational efficiency and uncertainty in modeling are highlighted. We conclude that DEM is an effective method for simulating soil and plant dynamics in SPMI systems related to the field of agriculture and food production. However, there are still some aspects that need to be examined in the future.
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Galina Guentchev, Erika J. Palin, Jason A. Lowe, and Mark Harrison
- Climate Services, Vol 30, Iss , Pp 100352- (2023)
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Upscaling, Scaling up, Climate services, Prototyping, Pilot projects, Meteorology. Climatology, QC851-999, Social sciences (General), and H1-99
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Translating climate data and information for use in real-world applications often involves the development of climate service prototypes within the constraints of pilot or demonstration projects. However, these services rarely make the transition from prototype to fully-fledged, transferrable and/or repeatable climate services – that is, there are problems with upscaling them beyond the pilot/demonstrator phase.In this paper we are using the mainstream understanding of the three main types of upscaling: reaching many (horizontal), enhancing the enabling environment (vertical), and expanding the product or service’s features (functional). Through a review of the general upscaling literature, coupled with focused interviews with weather/climate services experts, we found that there are common barriers to, and enablers for, successful upscaling – many of which apply to the specific case of upscaling climate services. Barriers include problems with leadership (e.g. the absence of a long-term vision and/or strategy for upscaling); limited funding or lack of a business model for the service at scale; issues with the enabling environment for upscaling (e.g. poor policy context, inadequate governance systems); and poor user engagement.Lessons learned from the literature in the context of upscaling climate services include planning for it as early as possible in the prototyping process; including a monitoring, evaluation and learning approach to inform upscaling progress; taking actions to foster and enhance the enabling environment; and searching for a balance between generic solutions and fit-for-purpose products.
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Daniel Varecha, Ján Galík, František Brumerčík, Róbert Kohár, Rudolf Madaj, Mário Drbúl, Adam Glowacz, Witold Glowacz, and Hui Liu
- Communications, Vol 25, Iss 2, Pp B140-B156 (2023)
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rapid prototyping, photogrammetry-3d projection additive manufacturing, 2d/3d roughness of pa12, selective laser sintering (sls) multi-jet fusion (mjf), Transportation and communications, HE1-9990, Science, Transportation engineering, and TA1001-1280
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The authors of this manuscript present development of a prototype protective UV-C half-face mask. The first stage of this study focuses on proposing a UV-C half-face mask design and the second phase investigates the quality of printings, 3D/2D roughness and porousness of three different printed samples of PA12. Development of the protective half-face mask used the non-destructive technology of 3D scanning of the human body by the Ein Scan scanner. As a part of the experiment, three samples were prepared with Sinterit Lisa, EOS Formiga and HP jet fusion printers. SLS and MJF technology were used during the experiment. The experimental observation of the structure of the surface was secured using the Alicona Infinite focus G5 device. The conclusions present the study's results and the authors' recommendations for other developers dealing with the development of the protective face masks.
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Rahul Gupta, Maher Assaad, Muhammad Akmal Chaudhary, and Mohammad Hashmi
- Electronics, Vol 12, Iss 1991, p 1991 (2023)
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Wilkinson power divider, design flexibility, frequency-dependent complex impedance transformation, Electronics, and TK7800-8360
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Flexible design schemes for single- and dual-band power dividers terminated in arbitrary port impedances are proposed in this paper. The proposed architecture provides the inherent impedance transformation to real, complex, and frequency-dependent complex impedances at the input and output port terminations. Furthermore, the proposed design is supported by flexible design procedures with independent design variables to enhance rapid prototyping in microstrip technology. It is demonstrated that the presence of independent design variables enhances the design flexibility for varied ranges of frequency and impedance transformation ratios. Two different prototypes, one each demonstrating single- and dual-band performances, are developed to validate the performance of the reported designs with real and frequency-dependent complex port impedances. The prototypes exhibit excellent agreements between the simulated and measured results. The single-band impedance transforming power divider (ITPD) possesses a low-amplitude imbalance of 0.5 dB, a phase imbalance of less than ±0.5∘, and an isolation of −26 dB at the design frequency of 5.8 GHz. The dual-band prototype also exhibits a low-amplitude imbalance of 0.5 dB and a phase imbalance of less than ±0.5∘ at both the design frequencies of 1 GHz and 2.6 GHz. The isolation is also better than −30 dB at both design frequencies. It is thus shown that the overall performance advances the state of the art in the design schemes of ITPDs.
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Shahid Hussain, Ants Kallaste, and Toomas Vaimann
- Energies, Vol 16, Iss 3840, p 3840 (2023)
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additive manufacturing, topology optimization, level set, synchronous reluctance machine, switch reluctance machine, ON-OFF method, and Technology
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Additive manufacturing (AM) or 3D printing has opened up new opportunities for researchers in the field of electrical machines, as it allows for more flexibility in design and faster prototyping, which can lead to more efficient and cost-effective production. An overview of the primary AM techniques utilized for designing electrical machines is presented in this paper. AM enables the creation of complex and intricate designs that are difficult or impossible to achieve using traditional methods. Topology Optimization (TO) can be used to optimize the design of parts for various purposes such as weight, thermal, material usage and structural performance. This paper primarily concentrates on the most recent studies of the AM and TO of the reluctance machines. The integration of AM with TO can enhance the design and fabrication process of magnetic components in electrical machines by overcoming current manufacturing limitations and enabling the exploration of new design possibilities. The technology of AM and TO both have limitations and challenges which are discussed in this paper. Overall, the paper offers a valuable resource for researchers and practitioners working in the field of AM and TO of electrical machines.
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Antti Isosalo, Johirul Islam, Henrik Mustonen, Ella Räinä, Satu I. Inkinen, Mikael Brix, Tanesh Kumar, Jarmo Reponen, Miika T. Nieminen, and Erkki Harjula
- Finnish Journal of eHealth and eWelfare, Vol 15, Iss 1 (2023)
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radiology, image processing, health technology, telemedicine, cloud computing, internet of things, Computer applications to medicine. Medical informatics, R858-859.7, Public aspects of medicine, and RA1-1270
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Computational requirements for data processing at different stages of the radiology value chain are increasing. Cone beam computed tomography (CBCT) is a diagnostic imaging technique used in dental and extremity imaging, involving a highly demanding image reconstruction task. In turn, artificial intelligence (AI) assisted diagnostics are becoming increasingly popular, thus increasing the use of computation resources. Furthermore, the need for fully independent imaging units outside radiology departments and with remotely performed diagnostics emphasize the need for wireless connectivity between the imaging unit and hospital infrastructure. In this feasibility study, we propose an approach based on a distributed edge-cloud computing platform, consisting of small-scale local edge nodes, edge servers with traditional cloud resources to perform data processing tasks in radiology. We are interested in the use of local computing resources with Graphics Processing Units (GPUs), in our case Jetson Xavier NX, for hosting the algorithms for two use-cases, namely image reconstruction in cone beam computed tomography and AI-assisted cancer detection from mammographic images. Particularly, we wanted to determine the technical requirements for local edge computing platform for these two tasks and whether CBCT image reconstruction and breast cancer detection tasks are possible in a diagnostically acceptable time frame. We validated the use-cases and the proposed edge computing platform in two stages. First, the algorithms were validated use-case-wise by comparing the computing performance of the edge nodes against a reference setup (regular workstation). Second, we performed qualitative evaluation on the edge computing platform by running the algorithms as nanoservices. Our results, obtained through real-life prototyping, indicate that it is possible and technically feasible to run both reconstruction and AI-assisted image analysis functions in a diagnostically acceptable computing time. Furthermore, based on the qualitative evaluation, we confirmed that the local edge computing capacity can be scaled up and down during runtime by adding or removing edge devices without the need for manual reconfigurations. We also found all previously implemented software components to be transferable as such. Overall, the results are promising and help in developing future applications, e.g., in mobile imaging scenarios, where such a platform is beneficial.
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Arzu Turan Dincel, Sadiye Nergis Tural Polat, and Pelin Sahin
- Fractal and Fractional, Vol 7, Iss 346, p 346 (2023)
- Subjects
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numerical approximation for FDEs, Hermite wavelets, operational matrix for fractional derivatives, Thermodynamics, QC310.15-319, Mathematics, QA1-939, Analysis, and QA299.6-433
- Abstract
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Nonlinear fractional differential equations (FDEs) constitute the basis for many dynamical systems in various areas of engineering and applied science. Obtaining the numerical solutions to those nonlinear FDEs has quickly gained importance for the purposes of accurate modelling and fast prototyping among many others in recent years. In this study, we use Hermite wavelets to solve nonlinear FDEs. To this end, utilizing Hermite wavelets and block-pulse functions (BPF) for function approximation, we first derive the operational matrices for the fractional integration. The novel contribution provided by this method involves combining the orthogonal Hermite wavelets with their corresponding operational matrices of integrations to obtain sparser conversion matrices. Sparser conversion matrices require less computational load, and also converge rapidly. Using the generated approximate matrices, the original nonlinear FDE is converted into an algebraic equation in vector-matrix form. The obtained algebraic equation is then solved using the collocation points. The proposed method is used to find a number of nonlinear FDE solutions. Numerical results for several resolutions and comparisons are provided to demonstrate the value of the method. The convergence analysis is also provided for the proposed method.
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43. The application of additive manufacturing technology in pelvic surgery: A bibliometrics analysis [2023]
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Jian Li, Jiani Wang, Jia Lv, Junjun Bai, Shichao Meng, Jinxuan Li, and Hua Wu
- Frontiers in Bioengineering and Biotechnology, Vol 11 (2023)
- Subjects
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pelvic surgery, three-dimensional printing technology, additive manufacturing technology, rapid prototyping, bibliometric analysis, Biotechnology, and TP248.13-248.65
- Abstract
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With the development of material science, additive manufacturing technology has been employed for pelvic surgery, addressing the challenges, such as the complex structure of the pelvis, difficulty in exposing the operative area, and poor visibility, of the traditional pelvic surgery. However, only limited studies have been done to review the research hotspots and trends of the additive manufacturing technology applied for pelvic surgery. In this study, we comprehensively analyzed the literatures related to additive manufacturing technology in pelvic surgery by a bibliometrics analysis and found that additive manufacturing technology is widely used in several aspects of preoperative diagnosis, preoperative planning, intraoperative navigation, and personalized implants for pelvic surgery. Firstly, we searched and screened 856 publications from the Web of Science Core Collection (WoSCC) with TS = (3D printing OR 3D printed OR three-dimensional printing OR additive manufacturing OR rapid prototyping) AND TS = (pelvis OR sacrum OR ilium OR pubis OR ischium OR ischia OR acetabulum OR hip) as the search strategy. Then, 565 of these were eliminated by evaluating the titles and abstracts, leaving 291 pieces of research literature whose relevant information was visually displayed using VOSviewer. Furthermore, 10 publications with high citations were selected by reading all publications extensively for carefully evaluating their Titles, Purposes, Results, Limitations, Journal of affiliation, and Citations. Our results of bibliometric analysis demonstrated that additive manufacturing technology is increasingly applied in pelvic surgery, providing readers with a valuable reference for fully comprehending the research hotspots and trends in the application of additive manufacturing technology in pelvic surgery.
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Ali A. Mohammed, Jingqi Miao, Ieva Ragaisyte, Alexandra E. Porter, Connor W. Myant, and Alessandra Pinna
- Heliyon, Vol 9, Iss 4, Pp e14682- (2023)
- Subjects
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Super paramagnetic iron oxide nanoparticles (SPIONs), 3D printing, Additive manufacturing, Hydrogels, Magnetic stimuli, VAT photopolymerization, Science (General), Q1-390, Social sciences (General), and H1-99
- Abstract
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Magnetic-stimuli responsive hydrogels are quickly becoming a promising class of materials across numerous fields, including biomedical devices, soft robotic actuators, and wearable electronics. Hydrogels are commonly fabricated by conventional methods that limit the potential for complex architectures normally required for rapidly changing custom configurations. Rapid prototyping using 3D printing provides a solution for this. Previous work has shown successful extrusion 3D printing of magnetic hydrogels; however, extrusion-based printing is limited by nozzle resolution and ink viscosity. VAT photopolymerization offers a higher control over resolution and build-architecture. Liquid photo-resins with magnetic nanocomposites normally suffer from nanoparticle agglomeration due to local magnetic fields. In this work, we develop an optimised method for homogenously infusing up to 2 wt % superparamagnetic iron oxide nanoparticles (SPIONs) with a 10 nm diameter into a photo-resin composed of water, acrylamide and PEGDA, with improved nanoparticle homogeneity and reduced agglomeration during printing. The 3D printed starfish hydrogels exhibited high mechanical stability and robust mechanical properties with a maximum Youngs modulus of 1.8 MPa and limited shape deformation of 10% when swollen. Each individual arm of the starfish could be magnetically actuated when a remote magnetic field is applied. The starfish could grab onto a magnet with all arms when a central magnetic field was applied. Ultimately, these hydrogels retained their shape post-printing and returned to their original formation once the magnetic field had been removed. These hydrogels can be used across a wide range of applications, including soft robotics and magnetically stimulated actuators.
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Muhammad Hamza Nazir, Ali H. Al-Marzouqi, Waleed Ahmed, and Essam Zaneldin
- Heliyon, Vol 9, Iss 4, Pp e15023- (2023)
- Subjects
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Natural fibers, Clay-based composites, Additive manufacturing, 3D printing, Sustainable environment, Science (General), Q1-390, Social sciences (General), and H1-99
- Abstract
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Natural fibers or their derivatives have gained significant attention as green fillers or reinforcement materials due to their abundant availability, environment-friendly nature and biodegradability for sustainable development. Despite the availability of modern alternatives such as concrete, glass-fiber/resin composites, steel, and plastics, there is still considerable demand for naturally occurring based materials for different applications due to their low cost, durability, strength, heat, sound, and fire-resistance characteristics. 3D printing has provided a novel approach to the development and advancement of natural fiber-based composite materials, as well as an important platform for the advancement of biomass materials toward intelligentization and industrialization. The features of 3D printing, particularly fast prototyping and small start-up, allow the easy fabrication of materials for a wide range of applications. This review highlights the current progress and potential commercial applications of 3D printed composites reinforced with natural fibers or biomass. This study discussed that 3D printing technology can be effectively utilized for different applications, including producing electroactive papers, fuel cell membranes, adhesives, wastewater treatment, biosensors, and its potential applications in the automobile, building, and construction industries. The research in the literature showed that even if the field of 3D printing has advanced significantly, problems still need to be solved, such as material incompatibility and material cost. Further studies could be conducted to improve and adapt the methods to work with various materials. More effort should be put into developing affordable printer technologies and materials that work with these printers to broaden the applications for 3D printed objects.
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Hamid Radmanesh and Ehsan Farmahini Farahani
- IET Electric Power Applications, Vol 17, Iss 4, Pp 441-451 (2023)
- Subjects
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electric machines, electric motors, finite element analysis, Applications of electric power, and TK4001-4102
- Abstract
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Abstract This study elaborates upon a new modular split‐tooth permanent magnet‐assisted switched reluctance motor (MSTPM‐SRM). In the proposed topology, the stator comprises six modular E‐cores in which the middle poles are split into two teeth. Two permanent magnets (PMs) are placed between each module's middle and side poles. Primarily, the proposed topology is introduced. Next, the principle of operation of the proposed topology are elucidated, and the magnetic equivalent circuit analysis is adopted in order to validate the operational basics. It is proved that the embedded PMs significantly increase the air‐gap's flux density and adjusts the poles' flux density. The flux density distributions, static, and steady‐state characteristics of the proposed MSTPM‐SRM motor and its PMless counterpart are extracted by utilising 2‐D finite element analysis. It is illustrated that the average torque of the proposed MSTPM‐SRM is dramatically increased compared to its PMless counterpart, especially at high excitation currents. Furthermore, the cogging torque analysis is done and it is shown that the proposed structure has approximately zero cogging torque. Finally, a prototyping version of the proposed motor is fabricated, and the experimental results are elicited. It is shown that the experimental results endorse the simulation results.
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47. A novel axial air‐gap transverse flux switching PM generator: Design, simulation and prototyping [2023]
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Aghil Ghaheri, Ebrahim Afjei, and Hossein Torkaman
- IET Electric Power Applications, Vol 17, Iss 4, Pp 452-463 (2023)
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AC machines, AC motor drives, AC motors, AC‐AC power convertors, AC‐DC power convertors, brushless machines, Applications of electric power, and TK4001-4102
- Abstract
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Abstract Wind energy as the cleanest source of renewable energy requires a highly efficient lightweight generator that provides maximum power density while having the least vibration noise and maintenance. In this study, an axial air gap transverse flux machine is presented, and all excitation sources are located in the stator. This structure provides lower core loss, weight and cost due to the full utilisation of the permanent magnets, SMC‐free structure and short magnetic flux path. In fact, by combining the features of a flux‐switching machine into a transverse flux generator with an axial air gap, it is possible to improve the performance of a direct‐drive wind turbine generator by overcoming traditional structures' challenges. To analyse the axial transverse flux switching permanent magnet generator performance characteristics, 3D finite element simulations have been performed, which have been validated by comparing them to the practical results of a single‐phase prototype. The results are in agreement with an acceptable error that is caused by manufacturing uncertainties.
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Cameron K. Brooks, Jack E. Peplinski, and Joshua M. Pearce
- Inventions, Vol 8, Iss 61, p 61 (2023)
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3D printing, additive manufacturing, breakout, chip shortage, design, electronics, Engineering machinery, tools, and implements, TA213-215, Technological innovations. Automation, and HD45-45.2
- Abstract
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The COVID-19 pandemic exposed the vulnerability of global supply chains of many products. One area that requires improved supply chain resilience and that is of particular importance to electronic designers is the shortage of basic dual in-line package (DIP) electronic components commonly used for prototyping. This anecdotal observation was investigated as a case study of using additive manufacturing to enforce contact between premade, off-the-shelf conductors to allow for electrical continuity between two arbitrary points by examining data relating to the stock quantity of electronic components, extracted from Digi-Key Electronics. This study applies this concept using an open hardware approach for the design, testing, and use of a simple, parametric, 3-D printable invention that allows for small outline integrated circuit (SOIC) components to be used in DIP package circuits (i.e., breadboards, protoboards, etc.). The additive manufacture breakout board (AMBB) design was developed using two different open-source modelers, OpenSCAD and FreeCAD, to provide reliable and consistent electrical contact between the component and the rest of the circuit and was demonstrated with reusable 8-SOIC to DIP breakout adapters. The three-part design was optimized for manufacturing with RepRap-class fused filament 3-D printers, making the AMBB a prime candidate for use in distributed manufacturing models. The AMBB offers increased flexibility during circuit prototyping by allowing arbitrary connections between the component and prototyping interface as well as superior organization through the ability to color-code different component types. The cost of the AMBB is CAD $0.066/unit, which is a 94% saving compared to conventional PCB-based breakout boards. Use of the AMBB device can provide electronics designers with an increased selection of components for through-hole use by more than a factor of seven. Future development of AMBB devices to allow for low-cost conversion between arbitrary package types provides a path towards more accessible and inclusive electronics design as well as faster prototyping and technical innovation.
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Diego Anestor Coutinho, Pedro Lucas Siqueira Paulino, Arielli Ajudarte da Conceição, Sthefany Farias Vilela, Guilherme Pedro Aquino, Antonio Alves Ferreira Junior, and Evandro Cesar Vilas Boas
- Journal of Aerospace Technology and Management, Vol 15 (2023)
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Nanosatellites, Nanosats, Small satellites, IoT connectivity, Gamma radiation, Technology, Motor vehicles. Aeronautics. Astronautics, and TL1-4050
- Abstract
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This work presents the design and prototyping of two 1U standard CubeSats for the First Brazilian MCTI Satellite Olympiad, launching one in a stratospheric helium-filled balloon. The nanosatellites were designed for two missions: Internet of Things connectivity in remote areas based on CubeSat (IoSat) and low-orbit harmful gamma radiation mapping (LOHGRM). The IoSat mission aimed to provide server connectivity for a remote sensor network. The LOHGRM CubeSat was designed for sensing and mapping gamma radiation power levels in the satellite’s orbit to construct a heat map to study the gamma radiation effect on the equipment. The prototype’s performance was evaluated based on physical, mechanical, magnetic, thermal, and transmission characterization, with satisfactory results under test conditions. The LOHGRM mission test was carried out on the ground as proof of concept without flying while a stratospheric balloon launched the IoSat prototype. Due to restrictions imposed by the competition, the IoSat nanosatellite only captured and registered altitude, pressure, and temperature data without testing the communication payload. Instead, this data was sent to the ground station through the competition communication system and stored in a memory card to assess its operation during the flying. The satellite’s maximum altitude was 22.6 km, operating under –23.5 °C.
- Full text View record in DOAJ
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Samuel Neumark, Janine Noorloos, and Joseph Ferenbok
- Journal of Clinical and Translational Science, Vol 7, Pp 27-27 (2023)
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Medicine
- Abstract
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OBJECTIVES/GOALS: The goal of the Translational Research Program (TRP) at the University of Toronto is to provide structured and adaptive competency-based training around the translation, mobilization, implementation, and commercialization of research for the current and future Canadian healthcare workforce. METHODS/STUDY POPULATION: Guided by the Toronto Translational Framework, the TRP is a two-year hybrid master’s degree program that integrates courses, case-studies, mentorship, and experiential learning to facilitate real-world student-led translational projects. Focusing on skills development and competency-based assessment, the curriculum emphasizes ongoing reflection, interprofessional collaboration, and multidisciplinary problem-solving using human-centered principles. Learners identify problems using contextual inquiry to define unmet needs and frame design requirements. Systematic ideation is used to generate, select, and validate promising concepts for further iterative prototyping and evaluation. RESULTS/ANTICIPATED RESULTS: Throughout the program, students demonstrate a range of collaborative skills and activities around developing, assessing, and implementing new health interventions. Learners apply the Toronto Translational Framework and refine their professional competencies during the final year of the program in a student-led Capstone project. The unconventional combination of a guided framework and a learner-driven curriculum has produced over 120 graduates in a variety of careers within government, industry, clinical settings, and start-ups. The program’s focus on problem-solving and lifelong learning is growing Canada’s translational workforce and advancing translational health science education. DISCUSSION/SIGNIFICANCE: The TRP addresses the need to educate healthcare professionals in Canada about translational research and accelerate the transformation of scientific discoveries into tangible interventions that benefit human health, improve clinical medicine, and enhance patient care.
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Denny Trias Utomo, Mochammad Rifki Ulil Albaab, Ahmad Fahriyannur Rosyady, Adi Sucipto, and Sholihah Ayu Wulandari
- Journal of Electrical Engineering and Computer, Vol 5, Iss 1, Pp 1-3 (2023)
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matching fund, prototyping, immersive technology, Electrical engineering. Electronics. Nuclear engineering, and TK1-9971
- Abstract
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Sidoarjo Regency is a Delta Plain with an altitude between 0 to 25 m, a height of 0-3m with an area of 19,006 Ha, covering 29.99%, is a fishpond area located in the eastern part of the Central Region which has fresh water with an altitude of 3-10 meters above sea level is a residential area, trade and government. Covering 40.81%. The western region with an altitude of 10-25 meters above sea level is an agricultural area. [1],[2] The Matching Fund Program is a program funded by the Ministry of Education and Culture, Ministry of Research and Technology to strengthen cooperation between PTs and DUDI to jointly form the Merdeka Learning Ecosystem - Merdeka Campus. At the end of the program, a better and sustainable working relationship will be established between PT and DUDI, which is expected to contribute to solving real problems in the field or carrying out national strategic actions. [3] The method used on this project is prototyping, which is a system development method in which prototypes are built, tested and then reworked as necessary until acceptable results are achieved of the system or a complete product can be developed.
- Full text View record in DOAJ
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Laurențiu-Florin Constantinoiu, Mariana Bernardino, and Eugen Rusu
- Journal of Marine Science and Engineering, Vol 11, Iss 799, p 799 (2023)
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hydrographic survey, maritime unmanned systems, unmanned surface vehicle, CUBE, multibeam sonar, amphibious operations, Naval architecture. Shipbuilding. Marine engineering, VM1-989, Oceanography, and GC1-1581
- Abstract
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Maritime unmanned systems (MUS) have gained widespread usage in a diverse range of hydrographic survey activities, including harbor/port surveys, beach and coastline monitoring, environmental assessment, and military operations. The present article explains a validated, rapid, and reliable technique for processing hydrographic data that was obtained via an autonomous hydrographic survey, and which was executed by a prototype unmanned surface vessel (USV) belonging to the Unmanned Survey Solutions (USS) corporation. The experimentation was part of the annual Multinational Exercise Robotic Experimentation and Prototyping that was augmented by Maritime Unmanned Systems 22 (REPMUS22), which was held in the national waters of Portugal. The main objective of this experimentation was to assess the underwater environment over an ocean beach for an amphibious landing exercise. Moreover, the integration of the multibeam system with the autonomous prototype vessel was assessed. A short comparison between the USV survey and a traditional vessel multibeam survey is presented, whereby the advantages of performing an autonomous survey operation near the coastline is emphasized. A correlation between a known multibeam processing technique and the dissemination of a rapid but consistent product for operational use is described, highlighting the applicability of the technique for the data collected from small experimental platforms. Moreover, this study outlines the relationship between the particular errors observed in autonomous small vehicles and in conventional data processing methods. The resultant cartographic outputs from the hydrographic survey are presented, emphasizing the specific inaccuracies within the raw data and the suitability of distinct hydrographic products for various user domains.
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Arika Sari, Dina Octaria, Rahma Siska Utari, Somakim Somakim, Cecil Hiltrimartin, Yusuf Hartono, and Darmawijoyo Darmawijoyo
- JTAM (Jurnal Teori dan Aplikasi Matematika), Vol 7, Iss 2, Pp 349-360 (2023)
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algebra, development research, infographics, instagram, mathematics anxiety., Mathematics, and QA1-939
- Abstract
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Research is a descriptive research that aims to describe the product development process in the form of infographic learning media in algebra material through Instagram that is appropriate for students to use for independent learning activities. This research focuses on creating infographic media in algebra material through Instagram to reduce mathematics anxiety and improve learning outcomes. The method used in this research is development research using the Sadiman’s model. The stages in this development model are preliminary stage, prototyping stage, and final stage, which from three stages contain of nine steps, namely identification of needs, formulation of objectives, formulation of materials, formulation of success measurement tools, writing of media scripts, production, tests/trials, revisions and the final product. There were 34 students of seventh graders of junior high school participating in this study. Data was collected through interviews, observations, tests, and questionnaires. Data were analyzed quantitatively and qualitatively. The results of the validation test by experts show that 93% of infographics through Instagram as strengthening students' understanding are included in the valid category and are suitable for use in the learning process. In addition, as many as 88% of students experienced an increase in learning outcomes after learning to use infographics through Instagram which indicated that the level of student anxiety in learning mathematics had decreased.
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BUDHY SETIAWAN, DEVI NUSLIKA PURWANTI, and DENDA DEWATAMA
- Jurnal Elkomika, Vol 11, Iss 2 (2023)
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3d printer, as5600 magnetic encoder, bigtree, cartesian, firmware marlin, resume, Electrical engineering. Electronics. Nuclear engineering, and TK1-9971
- Abstract
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ABSTRAK Dalam sebuah perusahaan manufaktur, produk yang dihasilkan selalu mengalami proses pengembangan tertentu yang mencakup pembuatan desain hingga menjadi prototype dengan tujuan untuk memenuhi kebutuhan konsumen. Salah satu mesin yang tepat dan efektif untuk pembuatan prototype adalah 3D printer. Energi listrik dibutuhkan selama proses printing, jika suplai energi listrik terhenti maka mesin 3D printer akan berhenti bekerja. Sehingga ketika suplai energi listrik tersambung kembali proses printing harus mengulang dari awal. Hal ini menyebabkan kerugian material dan waktu, semakin besar ukuran protoype yang dicetak maka akan semakin besar kerugian material dan waktunya. Oleh karena itu, mesin 3D printer memerlukan suatu kemampuan untuk menyimpan data posisi dan melanjutkan proses printing berdasarkan data tersebut. Berdasarkan pengujian akurasi penyimpanan data posisi ekstruder terhadap sumbu X, Y, Z, menggunakan AS5600 magnetic encoder didapatkan persentase error sebesar 0.004928649% pada sumbu X, 0.025628032% pada sumbu Y, 0.020581289% pada sumbu Z. Kata kunci: 3D Printer, AS5600 Magnetic Encoder, Bigtree, Cartesian, Firmware Marlin, Resume ABSTRACT In a manufacturing company, the products produced always undergo a certain development process which includes making designs to becoming prototypes with the aim of meeting consumer needs. One of the right and effective machines for prototyping is a 3D printer. Electrical energy is needed during the printing process, if the supply of electrical energy stops, the 3D printer engine will stop working. So that when the supply of electrical energy is reconnected the printing process has to repeat from the beginning. This causes material and time losses, the larger the printed prototype size, the greater the material and time losses. Therefore, a 3D printer machine requires the ability to store position data and continue the printing process based on that data. Based on testing the accuracy of ekstruder position data storage on the X, Y, Z planes, using the AS5600 magnetic encoder, the percentage error is 0.004928649% on the X axis, 0.025628032% on the Y axis, 0.020581289% on the Z axis. Keywords: 3D Printer, AS5600 Magnetic Encoder, Bigtree, Cartesian, Marlin Firmware, Resume
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55. VALIDITY OF GUIDED INQUIRY-BASED LEARNING INSTRUMENT WITH GEOGEBRA APPLETS FOR TEACHING CIRCLES [2023]
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Stri Pertiwi, Mailizar Mailizar, and Elizar Elizar
- Kalamatika, Vol 8, Iss 1 (2023)
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Learning Media, Guided Inquiry, geogebra applet, Plomp development, Education, Education (General), L7-991, Mathematics, and QA1-939
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The guided inquiry learning model is a student activity that emphasizes maximally training critical thinking skills. The learning instruments developed must be adapted to the syntax/stages of the guided inquiry learning model. Several learning instruments have been developed to assist teachers in making teaching materials. However, many teachers have not mastered technology, especially learning media using applications. Therefore, teachers need learning applications in schools, such as the GeoGebra applet. This study aims to develop valid guided inquiry-based learning instruments using GeoGebra applets for circles. This research is development research employing Plomp’s model and involving preliminary research and prototyping stages. The data was collected by compiling the comments and input from the validator through validation sheets related to learning instruments (lesson plans, worksheets, and GeoGebra applets). The results of the data analysis showed that the learning instruments were declared valid with an average lesson plan score of 4.75, an average student worksheet validation score of 4.60, and an average value of the total validation of GeoGebra applets of 4.94. Further research should assess the practicality and effectiveness of the instruments.
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Janusz Telega, Piotr Kaczynski, Małgorzata A. Śmiałek, Piotr Pawlowski, and Ryszard Szwaba
- Materials, Vol 16, Iss 2866, p 2866 (2023)
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rapid prototyping, Selective Laser Melting SLM, Direct Metal Laser Sintering (DLMS) technology, additive manufacturing, compressor blade, experimental aerodynamics, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, and QC120-168.85
- Abstract
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This paper describes some insights on applicability of a Selective Laser Melting and Direct Metal Laser Sintering technology-manufactured turbine blade models for aerodynamic tests in a wind tunnel. The principal idea behind this research was to assess the possibilities of using ‘raw’ DLMS printed turbine blade models for gas-flow experiments. The actual blade, manufactured using the DLMS technology, is assessed in terms of surface quality (roughness), geometrical shape and size (outline), quality of counterbores and quality of small diameter holes. The results are evaluated for the experimental aerodynamics standpoint. This field of application imposes requirements that have not yet been described in the literature. The experimental outcomes prove the surface quality does not suffice to conduct quantitative experiments. The holes that are necessary for pressure measurements in wind tunnel experiments cannot be reduced below 1 mm in diameter. The dimensional discrepancies are on the level beyond acceptable. Additionally, the problem of ‘reversed tolerance’, with the material building up and distorting the design, is visible in elements printed with the DLMS technology. The results indicate the necessity of post-machining of the printed elements prior their experimental usage, as their features in the ‘as fabricated’ state significantly disturb the flow conditions.
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Josef Sedlak, Zdenek Joska, Jiri Jansky, Jan Zouhar, Stepan Kolomy, Martin Slany, Adam Svasta, and Jan Jirousek
- Materials, Vol 16, Iss 3268, p 3268 (2023)
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3D printing, FFF technology, aging, degradation factors, tensile test, hardness test, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, and QC120-168.85
- Abstract
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The Fused Filament Fabrication (FFF) method is an additive technology that is used for the creation of prototypes within Rapid Prototyping (RP) as well as for the creation of final components in piece or small-series production. The possibility of using FFF technology in the creation of final products requires knowledge of the properties of the material and, at the same time, how these properties change due to degradation effects. In this study, the mechanical properties of the selected materials (PLA, PETG, ABS, and ASA) were tested in their non-degenerate state and after exposure of the samples to the selected degradation factors. For the analysis, which was carried out by the tensile test and the Shore D hardness test, samples of normalized shape were prepared. The effects of UV radiation, high temperature environments, high humidity environments, temperature cycles, and exposure to weather conditions were monitored. The parameters obtained from the tests (tensile strength and Shore D hardness) were statistically evaluated, and the influence of degradation factors on the properties of individual materials was assessed. The results showed that even between individual manufacturers of the same filament there are differences, both in the mechanical properties and in the behavior of the material after exposure to degradation effects.
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Kaijie Song, Zidong Lin, Yongzhe Fa, Xuefeng Zhao, Ziqian Zhu, Wei Ya, Zhen Sun, and Xinghua Yu
- Metals, Vol 13, Iss 764, p 764 (2023)
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wire and arc additive manufacturing (WAAM), high-strength, low-alloy steels, microstructure evolution, mechanical properties, Mining engineering. Metallurgy, and TN1-997
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High-strength, low-alloy (HSLA) steel has attracted much attention in the manufacturing industry because of its good combination of high strength and toughness, low cost, and good formability. Wire and arc additive manufacturing (WAAM) technology can realize the rapid prototyping of HSLA steel parts. This study investigated a 26-layer HSLA steel component fabricated with the WAAM technique. The microstructure of the deposited wall of ER120S-G is mainly acicular ferrite, and there are longitudinal, preferentially growing dendrites along the deposition direction. With the deposition height accumulation, the top sample’s interlayer temperature increases and the amount of acicular ferrite in the microstructure decreases, while the amount of quasi-polygonal ferrite, Widmanstatten ferrite increases. The changes in microhardness were consistent with the corresponding microstructure gradients: the microhardness of the top sample showed a decreasing trend along the deposition direction, while the microhardness of the middle sample was uniform and stable. The present work shows that the mechanical properties of HSLA steel parts deposited using WAAM technology have good strength and toughness. The microstructure gradient of the sample along the deposition direction did not lead to a significant difference in the tensile strength of the sample at different heights. On the contrary, the ductility of the longitudinal sample is slightly lower than that of the transverse sample, indicating some anisotropy in the deposited sample, which is related to the directional growth of grains along the direction of heat flow. From the current work, the thin wall of HSLA steel prepared with the WAAM process has good mechanical properties, which indicates that it is feasible to replace the traditional processing method with the WAAM process to rapidly manufacture an HSLA steel structure meeting the performance requirements.
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Iurii N. Zgoda
- Naučno-tehničeskij Vestnik Informacionnyh Tehnologij, Mehaniki i Optiki, Vol 23, Iss 2, Pp 430-435 (2023)
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thin-walled shell structures, stress-strain state, deep learning, neural networks, computer modeling, julia programming language, Optics. Light, QC350-467, Electronic computers. Computer science, and QA75.5-76.95
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Computer modeling is one of the most common approaches to the analysis of thin-walled shell structures stress-strain state analysis. It requires considerable time costs and high-performance hardware, especially when it is necessary to conduct a comparative analysis of various shell configurations. In this paper, we propose the use of deep learning methods to improve performance of this process. The purpose of work is to develop methods for high-performance computer simulation of thin-walled shell structures using deep neural networks, allowing to take into account geometric and physical properties of the structure as well as the load applied to it. A training approach and deep neural network architecture were developed to perform computer modeling of the stress-strain state of the shell. To form a training dataset, a computational experiment was carried out to simulate 3904 different configurations of doubly curved shallow shells that differ in linear dimensions, curvature radii, and materials used. Based on this dataset, 30 deep neural networks with different architectures were trained. To determine the optimal architecture in terms of modeling accuracy, mean absolute percentage error with clipping near-zero samples was calculated for each of the neural networks based on the test dataset. A network has been developed that allows calculating the stress-strain state of different shell configurations under an arbitrary uniformly distributed load. This is the first solution in the field of shell neural network modeling that allows us to vary the applied load, geometric and physical parameters of the shell and obtain calculation results at an arbitrary point of its middle surface. Performance measurements were carried out which show that the developed neural network allows simulating the stress-strain state of a shell structure 2117 times faster compared to the duration of solving the same problem by classical simulation. The modeling error using the network is at an acceptable level. An original architecture of a neural network for modeling the stress-strain state of shells was proposed which, through minor modifications, can be adapted for high-performance modeling of other building structure types. In accordance with the described architecture, a deep neural network was trained which reduces the computation time by several orders of magnitude. The results obtained are of high practical importance for researchers in the field of thin-walled shells modeling since they allow us to significantly reduce the time costs associated with conducting computational experiments. One of the possible applications for developed solution is prototyping of various shell configurations. Once prototyping is complete, the most efficient shell configurations can be explored in detail using classical computer simulation techniques.
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Muhammad Zulhilmi Zainuddin, Ahmad Adnan Abu Bakar, Ahmad Nurhelmy Adam, Shahino Mah Abdullah, Nizam Tamchek, Muhammad Syafiq Alauddin, Mohd Muzamir Mahat, Nophadon Wiwatcharagoses, Ahmad Alforidi, and Mohd Ifwat Mohd Ghazali
- Polymers, Vol 15, Iss 1849, p 1849 (2023)
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additive manufacturing, stereolithography (SLA), polyurethane acrylate, polyhydroxybutyrate, medical application, Organic chemistry, and QD241-441
- Abstract
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Today, additive manufacturing (AM) is considered one of the vital tenets of the industry 4.0 revolution due to its high productivity, decentralized production and rapid prototyping. This work aims to study the mechanical and structural properties of polyhydroxybutyrate as an additive in blend materials and its potential in medical applications. PHB/PUA blend resins were formulated with 0 wt.%, 6 wt.%, 12 wt.% and 18 wt.% of PHB concentration. Stereolithography or an SLA 3D printing technique were used to evaluate the printability of the PHB/PUA blend resins. Additionally, from FESEM analysis, a change was observed in PUA’s microstructure, with an additional number of voids spotted. Furthermore, from XRD analysis, as PHB concentration increased, the crystallinity index (CI) also increased. This indicates the brittleness properties of the materials, which correlated to the weak performance of the tensile and impact properties. Next, the effect of PHB loading concentration within PHB/PUA blends and aging duration towards the mechanical performance of tensile and impact properties was also studied by using analysis of variance (ANOVA) with a two-way method. Finally, 12 wt.% of PHB/PUA was selected to 3D print the finger splint due to its characteristics, which are compatible to be used in finger bone fracture recovery.
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61. Methods to Reduce Energy and Polymer Consumption for Fused Filament Fabrication 3D Printing [2023]
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Owen James Harding, Christian Andrew Griffiths, Andrew Rees, and Dimitrios Pletsas
- Polymers, Vol 15, Iss 1874, p 1874 (2023)
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3D printing, fused filament fabrication, fused deposition modelling, power efficiency, manufacturing optimisation, polylactic acid (PLA), Organic chemistry, and QD241-441
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Fused Filament Fabrication (FFF) 3D printing is an additive technology used to manufacture parts. Used in the engineering industry for prototyping polymetric parts, this disruptive technology has been adopted commercially and there are affordable printers on the market that allow for at-home printing. This paper examines six methods of reducing the energy and material consumption of 3D printing. Using different commercial printers, each approach was investigated experimentally, and the potential savings were quantified. The modification most effective at reducing energy consumption was the hot-end insulation, with savings of 33.8–30.63%, followed by the sealed enclosure, yielding an average power reduction of 18%. For material, the most influential change was noted using ‘lightning infill’, reducing material consumption by 51%. The methodology includes a combined energy- and material-saving approach in the production of a referenceable ‘Utah Teapot’ sample object. Using combined techniques on the Utah Teapot print, the material consumption was reduced by values between 55.8% and 56.4%, and power consumption was reduced by 29% to 38%. The implementation of a data-logging system allowed us to identify significant thermal management and material usage opportunities to minimise power consumption, providing solutions for a more positive impact on the sustainable manufacturing of 3D printed parts.
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62. Process Parameter Prediction for Fused Deposition Modeling Using Invertible Neural Networks [2023]
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Lukas Pelzer, Andrés Felipe Posada-Moreno, Kai Müller, Christoph Greb, and Christian Hopmann
- Polymers, Vol 15, Iss 1884, p 1884 (2023)
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additive manufacturing, fused deposition modeling, neural network, part quality, process parameters, production management, Organic chemistry, and QD241-441
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Additive manufacturing has revolutionized prototyping and small-scale production in the past years. By creating parts layer by layer, a tool-less production technology is established, which allows for rapid adaption of the manufacturing process and customization of the product. However, the geometric freedom of the technologies comes with a large number of process parameters, especially in Fused Deposition Modeling (FDM), all of which influence the resulting part’s properties. Since those parameters show interdependencies and non-linearities, choosing a suitable set to create the desired part properties is not trivial. This study demonstrates the use of Invertible Neural Networks (INN) for generating process parameters objectively. By specifying the desired part in the categories of mechanical properties, optical properties and manufacturing time, the demonstrated INN generates process parameters capable of closely replicating the desired part. Validation trials prove the precision of the solution with measured properties achieving the desired properties to up to 99.96% and a mean accuracy of 85.34%.
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Jack Grubbs, Bryer C. Sousa, and Danielle L. Cote
- Polymers, Vol 15, Iss 1945, p 1945 (2023)
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additive manufacturing, FFF, PLA, mechanical properties, dimensional accuracy, optimization, Organic chemistry, and QD241-441
- Abstract
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Developments in polymer 3D printing (3DP) technologies have expanded their scope beyond the rapid prototyping space into other high-value markets, including the consumer sector. Processes such as fused filament fabrication (FFF) are capable of quickly producing complex, low-cost components using a wide variety of material types, such as polylactic acid (PLA). However, FFF has seen limited scalability in functional part production partly due to the difficulty of process optimization with its complex parameter space, including material type, filament characteristics, printer conditions, and “slicer” software settings. Therefore, the aim of this study is to establish a multi-step process optimization methodology—from printer calibration to “slicer” setting adjustments to post-processing—to make FFF more accessible across material types, using PLA as a case study. The results showed filament-specific deviations in optimal print conditions, where part dimensions and tensile properties varied depending on the combination of nozzle temperature, print bed conditions, infill settings, and annealing condition. By implementing the filament-specific optimization framework established in this study beyond the scope of PLA, more efficient processing of new materials will be possible for enhanced applicability of FFF in the 3DP field.
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Ju-Yong Lee, Min-Ha Oh, Joo-Hyeon Park, Se-Hun Kang, and Seung-Kyun Kang
- Polymers, Vol 15, Iss 2003, p 2003 (2023)
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elastic soft material, 3D printing, negative Poisson’s ratio structure, conductive composite material, Organic chemistry, and QD241-441
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Three-dimensional (3D) printing has various applications in many fields, such as soft electronics, robotic systems, biomedical implants, and the recycling of thermoplastic composite materials. Three-dimensional printing, which was only previously available for prototyping, is currently evolving into a technology that can be utilized by integrating various materials into customized structures in a single step. Owing to the aforementioned advantages, multi-functional 3D objects or multi-material-designed 3D patterns can be fabricated. In this study, we designed and fabricated 3D-printed expandable structural electronics in a substrateless auxetic pattern that can be adapted to multi-dimensional deformation. The printability and electrical conductivity of a stretchable conductor (Ag-RTV composite) were optimized by incorporating a lubricant. The Ag-RTV and RTV were printed in the form of conducting voxels and frame voxels through multi-nozzle printing and were arranged in a negative Poisson’s ratio pattern with a missing rib structure, to realize an expandable passive component. In addition, the expandable structural electronics were embedded in a soft actuator via one-step printing, confirming the possibility of fabricating stable interconnections in expanding deformation via a missing rib pattern.
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Antoni Pagés-Llobet, Francesc X. Espinach, Fernando Julián, Helena Oliver-Ortega, and José Alberto Méndez
- Polymers, Vol 15, Iss 2019, p 2019 (2023)
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additive manufacturing, FDM (Fused Deposition Modeling), Poly(lactic acid), mechanical properties, interface, cristallinity, Organic chemistry, and QD241-441
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FDM (Fused Deposition Modeling) is one of the most used and industrially applied additive manufacturing processes due to its fast prototyping and manufacturing, simplicity, and low cost of the equipment. However, the mechanical properties of the printed products have a large dependence on orientation and interface strength between layers which is mainly related to the thermal union obtained. This thermal union has a large dependence on the melting and cooling down process. Additionally, the materials used must be extruded in a continuous filament before their use, which limits the materials used. However, a pellet extruder could be used directly in the printing equipment, avoiding filament extrusion. In this work, specimens of PLA (Poly(lactic acid)) with different bead orientations have been produced via filament or pellet extrusion to compare the effect of the different melting processes in the manufacturing methodology. Pellet extruded specimens showed higher infill and mechanical properties. These results were related to better adhesion between layers due to the longer melting and cooling process. The result was confirmed using DSC and XRD techniques, where a higher crystallinity was observed. A bicomponent specimen (50% pellet–50% filament) was prepared and tested, showing higher mechanical results than expected, which was, again, due to the better thermal union obtained in the pellet extruder.
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Laurent Gole, Feng Liu, Kok Haur Ong, Longjie Li, Hao Han, David Young, Gabriel Pik Liang Marini, Aileen Wee, Jingmin Zhao, Huiying Rao, Weimiao Yu, and Lai Wei
- Scientific Reports, Vol 13, Iss 1, Pp 1-12 (2023)
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Medicine and Science
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Abstract The novel targeted therapeutics for hepatitis C virus (HCV) in last decade solved most of the clinical needs for this disease. However, despite antiviral therapies resulting in sustained virologic response (SVR), a challenge remains where the stage of liver fibrosis in some patients remains unchanged or even worsens, with a higher risk of cirrhosis, known as the irreversible group. In this study, we provided novel tissue level collagen structural insight into early prediction of irreversible cases via image based computational analysis with a paired data cohort (of pre- and post-SVR) following direct-acting-antiviral (DAA)-based treatment. Two Photon Excitation and Second Harmonic Generation microscopy was used to image paired biopsies from 57 HCV patients and a fully automated digital collagen profiling platform was developed. In total, 41 digital image-based features were profiled where four key features were discovered to be strongly associated with fibrosis reversibility. The data was validated for prognostic value by prototyping predictive models based on two selected features: Collagen Area Ratio and Collagen Fiber Straightness. We concluded that collagen aggregation pattern and collagen thickness are strong indicators of liver fibrosis reversibility. These findings provide the potential implications of collagen structural features from DAA-based treatment and paves the way for a more comprehensive early prediction of reversibility using pre-SVR biopsy samples to enhance timely medical interventions and therapeutic strategies. Our findings on DAA-based treatment further contribute to the understanding of underline governing mechanism and knowledge base of structural morphology in which the future non-invasive prediction solution can be built upon.
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Stefan Tabacu, Ana Badea, and Alina Sandu
- Sustainability, Vol 15, Iss 6805, p 6805 (2023)
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auxetic tetra-anti-chiral, compression, performance indicators, strain analysis, Environmental effects of industries and plants, TD194-195, Renewable energy sources, TJ807-830, Environmental sciences, and GE1-350
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Cellular structures subjected to compressive loads provide a reliable solution for improving safety. As a member of cellular material, auxetic metamaterials can enhance performance according to the definition of the negative Poisson ratio. In conjunction with Rapid Prototyping by Additive Manufacturing methods, complex structures can be manufactured using a wide range of materials. This paper debuts the development process of a reliable material model that is useful for the numerical simulation, and further details and investigates the performance indicators of an auxetic structure, namely anti-tetra-chiral. These indicators are related to the force developed during the plateau stage, the length of the plateau stage, and the nominal dimensions of the structure to avoid buckling during compression. Two new indicators discussed in this paper aim to provide a complete set of performance indicators. The first analytical solution provides the displacement of the circular nodes during the compression. The second analytical solution estimates the strain developed in the ligaments. Considering the performance of the processed material, this analysis aims to determine whether the structure can develop the complete plateau stage or whether premature failure will occur.
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Emel Alkim, Heidi Dowst, Julie DiCarlo, Lacey E. Dobrolecki, Anadulce Hernández-Herrera, David A. Hormuth, Yuxing Liao, Apollo McOwiti, Robia Pautler, Mothaffar Rimawi, Ashley Roark, Ramakrishnan Rajaram Srinivasan, Jack Virostko, Bing Zhang, Fei Zheng, Daniel L. Rubin, Thomas E. Yankeelov, and Michael T. Lewis
- Tomography, Vol 9, Iss 66, Pp 810-828 (2023)
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magnetic resonance imaging (MRI), multi-omics, breast cancer, cancer informatics, cancer modeling, radiomics, Computer applications to medicine. Medical informatics, and R858-859.7
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Co-clinical trials are the concurrent or sequential evaluation of therapeutics in both patients clinically and patient-derived xenografts (PDX) pre-clinically, in a manner designed to match the pharmacokinetics and pharmacodynamics of the agent(s) used. The primary goal is to determine the degree to which PDX cohort responses recapitulate patient cohort responses at the phenotypic and molecular levels, such that pre-clinical and clinical trials can inform one another. A major issue is how to manage, integrate, and analyze the abundance of data generated across both spatial and temporal scales, as well as across species. To address this issue, we are developing MIRACCL (molecular and imaging response analysis of co-clinical trials), a web-based analytical tool. For prototyping, we simulated data for a co-clinical trial in “triple-negative” breast cancer (TNBC) by pairing pre- (T0) and on-treatment (T1) magnetic resonance imaging (MRI) from the I-SPY2 trial, as well as PDX-based T0 and T1 MRI. Baseline (T0) and on-treatment (T1) RNA expression data were also simulated for TNBC and PDX. Image features derived from both datasets were cross-referenced to omic data to evaluate MIRACCL functionality for correlating and displaying MRI-based changes in tumor size, vascularity, and cellularity with changes in mRNA expression as a function of treatment.
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69. Virtual and Physical Prototyping [2023]
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additive manufacturing, 3d printing, materials mechanics, manufacturing engineering, industrial engineering, Science, Manufactures, and TS1-2301
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Zihua Zhang, Zhenjiang Zhu, Yongbing Feng, and Ran Li
- Advances in Mechanical Engineering, Vol 15 (2023)
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Mechanical engineering and machinery and TJ1-1570
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To overcome the inefficiency of slicing process of rapid prototyping based on STL models, an improved slicing algorithm is proposed. The method builds integral topology of STL models in advance using a Hash table, which enables to get contours directly, and then reduces the search range in slicing by establishing the slicing relation matrix, which can effectively reduce the time cost of slicing. It has been demonstrated that the algorithm has nearly linear time complexity. The method is proved to be effective and efficient through application cases, and the results show better performance than other existing algorithms, especially when the STL model is complex or large.
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71. Simulation device for shoulder reductions: overview of prototyping, testing, and design instructions [2023]
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Sorab Taneja, Will Tenpas, Mehul Jain, Peter Alfonsi, Abhinav Ratagiri, Ann Saterbak, and Jason Theiling
- Advances in Simulation, Vol 8, Iss 1, Pp 1-10 (2023)
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Shoulder reduction, Simulation device, Traction-countertraction, External rotation maneuver, Computer applications to medicine. Medical informatics, and R858-859.7
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Abstract Background Shoulder dislocations are common occurrences, yet there are few simulation devices to train medical personnel on how to reduce these dislocations. Reductions require a familiarity with the shoulder and a nuanced motion against strong muscle tension. The goal of this work is to describe the design of an easily replicated, low-cost simulator for training shoulder reductions. Materials and methods An iterative, stepwise engineering design process was used to design and implement ReducTrain. A needs analysis with clinical experts led to the selection of the traction-countertraction and external rotation methods as educationally relevant techniques to include. A set of design requirements and acceptance criteria was established that considered durability, assembly time, and cost. An iterative prototyping development process was used to meet the acceptance criteria. Testing protocols for each design requirement are also presented. Step-by-step instructions are provided to allow the replication of ReducTrain from easily sourced materials, including plywood, resistance bands, dowels, and various fasteners, as well as a 3D-printed shoulder model, whose printable file is included at a link in the Additional file 1: Appendix. Results A description of the final model is given. The total cost for all materials for one ReducTrain model is under US $200, and it takes about 3 h and 20 min to assemble. Based on repetitive testing, the device should not see any noticeable changes in durability after 1000 uses but may exhibit some changes in resistance band strength after 2000 uses. Discussion The ReducTrain device fills a gap in emergency medicine and orthopedic simulation. Its wide variety of uses points to its utility in several instructional formats. With the rise of makerspaces and public workshops, the construction of the device can be easily completed. While the device has some limitations, its robust design allows for simple upkeep and a customizable training experience. Conclusion A simplified anatomical design allows for the ReducTrain model to serve as a viable training device for shoulder reductions.
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Nana Sepriyanti, Syafruddin Nurdin, Martin Kustati, Wan Nasir, Juli Afriadi, and Aniswita Aniswita
- Aksioma: Jurnal Program Studi Pendidikan Matematika, Vol 12, Iss 1, Pp 501-512 (2023)
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design research, islamic integrated mathematics, textbook, Education, Mathematics, and QA1-939
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Many integrated textbooks between mathematics and another fields such as, music, culture, linguistics, etc. This study developed a valid, practical, and effective Islamic integrated mathematics textbooks for junior high/MTs students grade VII. This study is a developmental research by adopting Plomp model which consists of three phases i.e. preliminary research, prototype stage (developmental or prototyping phase), and assessment phase. The developed textbook has been validated by mathematicians, design experts, and linguists. The research data were collected using observation, interviews, questionnaires and test. Data processing in this study was carried out using quantitative decriptive and qualitative decriptive analysis. The results showed that the Islamic integrated mathematics textbooks for Junior High/MTs students is properly and well developed and applicable as the teaching materials in learning mathematics. The valid criterion is because the textbooks are developed in accordance with the principles of the scientific and logical knowledge. The practical criterion is because the textbooks are applicable in accordance with the settings that have been designed and developed. The effective criterion is because the textbooks can improve student’s mathematics ability.
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Armiati Armiati and Isra Hidayati
- Aksioma: Jurnal Program Studi Pendidikan Matematika, Vol 12, Iss 1, Pp 625-635 (2023)
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Education, Mathematics, and QA1-939
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Abstrak Trigonometri merupakan salah satu topik dalam matematika yang dipandang sulit oleh siswa SMA. Salah satu penyebab kesulitan siswa dalam pembelajaran matematika adalah kecemasan matematis siswa yang masih cukup tinggi. Untuk itu dibutuhkan sebuah desain pembelajaran yang dapat mengatasi permasalahan tersebut. Penelitian ini bertujuan untuk mengetahui keefektifan desain pembelajaran trigonometri berbasis contextual teaching and learning bernuansa etnomatematika Melayu Riau terhadap kecemasan matematis siswa. Desain pembelajaran dikembangkan dengan menggabungkan dua jenis penelitian desain, yaitu model Plomp dan model Gravemeijer dan Cobb. Berdasarkan kombinasi kedua model tersebut, tahapan penelitian ini terdiri dari : (1) tahap investigasi awal, (2) tahap pengembangan atau prototyping, dan (3) tahap penilaian. Subyek penelitian ini adalah siswa kelas X SMAN 1 Rumbio Jaya. Teknik pengumpulan data yang digunakan untuk melihat keefektifan adalah angket kecemasan matematis. Hasilnya adalah desain pembelajaran trigonometri berbasis contextual teaching and learning yang dikembangkan berdampak positif terhadap kecemasan matematis siswa. Kecemasan matematis siswa menurun dari rata-rata skor 72,85 atau berada pada kategori berat menjadi 62,91 atau berada pada kategori sedang setelah menggunakan desain pembelajaran trigonometri berbasis contextual teaching and learning bernuansa etnomatematika Melayu Riau. Abstract Trigonometry is a topic in mathematics that is considered difficult by high school students. One of the causes of students' difficulties in learning mathematics is students' mathematical anxiety which is still quite high. For that we need a learning design that can overcome these problems. This study aims to determine the effectiveness of trigonometric learning designs based on contextual teaching and learning with Riau Malay ethnomathematics nuances on students' mathematical anxiety. The learning design was developed by combining two types of design research, namely the Plomp model and the Gravemeijer and Cobb model. Based on the combination of the two models, the stages of this research consist of: (1) the initial investigation stage, (2) the development or prototyping stage, and (3) the assessment stage. The subjects of this study were students of class X SMAN 1 Rumbio Jaya. The data collection technique used to see the effectiveness is a mathematical anxiety questionnaire. The result is a trigonometric learning design based on contextual teaching and learning that has been developed has a positive impact on students' mathematical anxiety. Students' mathematical anxiety decreased from an average score of 72.85 or in the heavy category to 62.91 or in the moderate category after using a trigonometric learning design based on contextual teaching and learning with Riau Malay ethnomathematics.
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Guilherme Martins, Carlos M. S. Vicente, and Marco Leite
- Applied Sciences, Vol 13, Iss 4429, p 4429 (2023)
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fused filament fabrication, polymer-metal adhesion, single-lap joints, carbon fiber, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
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Additive manufacturing (AM) is often used for prototyping; however, in recent years, there have been several final product applications, namely the development of polymer-metal hybrid (PMH) components that have emerged. In this paper, the objective is to characterize the adhesion of single-lap joints between two different materials: aluminium and a polymer-based material manufactured by fused filament fabrication (FFF). Single-lap joints were fabricated using an aluminium substrate with different surface treatments: sandpaper polishing (SP) and grit blasting (GB). Three filaments for FFF were tested: acrylonitrile butadiene styrene (ABS), polyamide (PA), and polyamide reinforced with short carbon fibers (PA + CF). To characterize the behaviour of these single-lap joints, mechanical tension loading tests were performed. The analysis of the fractured surface of the joints aimed to correlate the adhesion performance of each joint with the occurred failure mode. The obtained results show the impact of surface roughness (0.16 < Ra < 1.65 µm) on the mechanical properties of the PMH joint. The ultimate lap shear strength (ULSS) of PMH single-lap joints produced by FFF (1 < ULSS < 6.6 MPa) agree with the reported values in the literature and increases for substrates with a higher surface roughness, remelting of the primer (PA and PA + CF), and higher stiffness of the polymer-based adherent.
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Nicola De Angelis, Andrea Amaroli, Maria Giovanna Sabbieti, Alessia Cappelli, Alberto Lagazzo, Claudio Pasquale, Fabrizio Barberis, and Dimitrios Agas
- Biology, Vol 12, Iss 536, p 536 (2023)
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additive manufacturing, rapid prototyping, polymer, dentition, oral disorder, bone defect, Biology (General), and QH301-705.5
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The concept of personalized medicine and overcoming healthcare inequalities have become extremely popular in recent decades. Polymers can support cost reductions, the simplicity of customized printing processes, and possible future wide-scale expansion. Polymers with β-tricalcium phosphate (TCP) are well known for their synergy with oral tissues and their ability to induce osteoconductivity. However, poor information exists concerning their properties after the printing process and whether they can maintain an unaffected biological role. Poly(ε-caprolactone) (PCL) polymer and PCL compounded with TCP 20% composite were printed with a Prusa Mini-LCD-®3D printer. Samples were sterilised by immersion in a 2% peracetic acid solution. Sample analyses were performed using infrared-spectroscopy and statical mechanical tests. Biocompatibility tests, such as cell adhesion on the substrate, evaluations of the metabolic activity of viable cells on substrates, and F-actin labelling, followed by FilaQuant-Software were performed using a MC3T3-E1 pre-osteoblasts line. PCL+β-TCP-20% composite is satisfactory for commercial 3D printing and appears suitable to sustain an ISO14937:200937 sterilization procedure. In addition, the proper actin cytoskeleton rearrangement clearly shows their biocompatibility as well as their ability to favour osteoblast adhesion, which is a pivotal condition for cell proliferation and differentiation.
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Catalin Marculescu, Petruta Preda, Tiberiu Burinaru, Eugen Chiriac, Bianca Tincu, Alina Matei, Oana Brincoveanu, Cristina Pachiu, and Marioara Avram
- Chemosensors, Vol 11, Iss 204, p 204 (2023)
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carbon-based electrochemical biosensors, 3D printing, flexible sensors, electrochemical impedance spectroscopy, Biochemistry, and QD415-436
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In recent research, 3D printing has become a powerful technique and has been applied in the last few years to carbon-based materials. A new generation of 3D-printed electrodes, more affordable and easier to obtain due to rapid prototyping techniques, has emerged. We propose a customizable fabrication process for flexible (and rigid) carbon-based biosensors, from biosensor design to printable conductive inks. The electrochemical biosensors were obtained on a 50 µm Kapton® (polyimide) substrate and transferred to a 500 µm PDMS substrate, using a 3D-extrusion-based printing method. The main features of our fabrication process consist of short-time customization implementation, fast small-to-medium batch production, ease of electrochemical spectroscopy measurements, and very good resolution for an extrusion-based printing method (100 µm). The sensors were designed for future integration into a smart wound dressing for wound monitoring and other biomedical applications. We increased their sensibility with electro-deposited gold nanoparticles. To assess the biosensors’ functionality, we performed surface functionalization with specific anti-N-protein antibodies for SARS-CoV 2 virus, with promising preliminary results.
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77. Studies on the Numerical Control Programming for Multi-Axis Machining of Turbomolecular Pump Rotor [2023]
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Teng-Hui Chen, Jeng-Nan Lee, Ming-Jhang Shie, and Yu-Cheng Chen
- Electronics, Vol 12, Iss 1281, p 1281 (2023)
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multi-axis machining, reverse engineering, rotor, turbomolecular pump (TMP), Electronics, and TK7800-8360
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Turbomolecular pumps (TMPs), boasting advantageous high pumping rates, stability, and cleanliness, have been widely used in the semiconductor and photoelectric industries. In the aviation industry, the lightweight rotors of turbomolecular pumps can enhance the performance of generators. With technological advancements and increased industrial performance demands, various designs for turbomolecular pump rotors utilizing twisted and curved blade surfaces have been proposed. This increase in complexity runs parallel with machining difficulties. Contact and noncontact reverse engineering equipment was used to reconstruct a computer-aided design (CAD) model of turbomolecular pump rotors. The machining of thin and long blades, cutting tool arrangement, and toolpath was planned. Postprocessing was used to convert the toolpath into numerical control (NC) programming codes, which were combined with solid model cutting simulation software to verify the efficacy of the generated machining NC program for turbomolecular pump rotors. A five-axis horizontal machining center (CK type) with aluminum alloy AL6061-T6 was used to conduct actual machining tests measuring the efficiency of the machining methods. The rapid prototyping (RP) blocks can be creatively used as a jig and stuffed between the blades to suppress the chatter problem during processing, and the roughness of the surface of the blades can be reduced from 4.4 μm to 1.3 μm. The processed rotor can meet the flow test requirements, and the overall research can be used as a reference for the industry.
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Tania Islam and Sayan Roy
- Electronics, Vol 12, Iss 1416, p 1416 (2023)
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wireless body area network, WBAN, multiband antenna, specific absorption rate, SAR, phantom, Electronics, and TK7800-8360
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In this work, we propose a novel multiband meander line antenna that can operate at three different frequency bands and offer suitable performance for wireless body area network (WBAN) applications. The net geometry of the antenna is 36 × 30 × 1.524 mm3. The proposed low-profile antenna is analytically modeled and designed in full wave ANSYS HFSS using Rogers TMM4 as the substrate, followed by in-lab prototyping. The designed antenna resonates at 4.5 GHz, 5 GHz, and 5.8 GHz and maintains positive gain, efficiency, and acceptable specific absorption rates at each resonant band. The effectiveness of the antenna for WBAN applications is demonstrated using an in-lab manufactured phantom. The fabrication process of the phantom is described, and dielectric characterization of the phantom mimicking different human tissue layers is presented. Considering results with and without human body phantoms available in the full wave ANSYS HFSS tool, a comparative analysis between simulated and measured antenna parameters concludes this work. Both the simulated and measured results show good agreement.
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Jacek Maciej Stankiewicz
- Energies, Vol 16, Iss 2950, p 2950 (2023)
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wireless power transfer, inductive power transfer, load resistance, numerical analysis, circuit analysis, and Technology
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We are currently seeing an increasing number of devices that support wireless power transfer (WPT) technology. In order to avoid early prototyping and carry out a series of experimental analyses, it was possible to use numerical methods at the design stage to estimate the potential power transfer and efficiency of the system. The purpose of this study is to present a method of analysis for a periodic wireless power transfer system, using periodically arranged planar coils with field and circuit models. A three-dimensional numerical model of a multi-segment charging system with periodic boundary conditions was solved with the finite element method (FEM). An equivalent circuit model of the periodic WPT system was proposed, and the required lumped parameters were obtained using analytical formulas. Mathematical formulas were supplemented with the analysis of several geometric variants, taking into account different sizes of transmitting and receiving coils, as well as different numbers of turns. Both proposed methods of analysis allowed for the determination of load resistance values at which the variants of WPT systems considered in the research had maximum efficiency. The ranges of load resistance values in which the efficiency of the system exceeded 50% were indicated. The results obtained are very helpful in the proper selection of the load resistance, without the need for multiple tests and their resulting multiple measurements. The results also showed that the proposed circuit model was able to achieve similar accuracy as the numerical model, and the complexity of the model and analysis was significantly reduced. The obtained results will allow the design of WPT systems with appropriate selections of load resistance to achieve maximum efficiency.
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Stefan Schoder, Jakob Schmidt, Andreas Fürlinger, Roppert Klaus, and Maurerlehner Paul
- Fluids, Vol 8, Iss 116, p 116 (2023)
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aeroacoustics, electric ducted fan, microperforated plate absorbers, eVTOL, Thermodynamics, QC310.15-319, Descriptive and experimental mechanics, and QC120-168.85
- Abstract
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New innovative green concepts in electrified vertical take-off and landing vehicles are currently emerging as a revolution in urban mobility going into the third dimension (vertically). The high population density of cities makes the market share highly attractive while posing an extraordinary challenge in terms of community acceptance due to the increasing and possibly noisier commuter traffic. In addition to passenger transport, package deliveries to customers by drones may enter the market. The new challenges associated with this increasing transportation need in urban, rural, and populated areas pose challenges for established companies and startups to deliver low-noise emission products. The article’s objective is to revisit the benefits and drawbacks of an affordable acoustic measurement campaign focused on early prototyping. In the very early phase of product development, available resources are often considerably limited. With this in mind, this article discusses the sound power results using the enveloping surface method in a typically available low-reflection room with a reflecting floor according to DIN EN ISO 3744:2011-02. The method is applied to a subsonic electric ducted fan (EDF) unit of a 1:2 scaled electrified vertical take-off and landing vehicle. The results show that considerable information at low costs can be gained for the early prototyping stage, despite this easy-to-use, easy-to-realize, and non-fine-tuned measurement setup. Furthermore, the limitations and improvements to a possible experimental setup are presented to discuss a potentially more ideal measurement environment. Measurements at discrete operating points and transient measurements across the total operating range were conducted to provide complete information on the EDF’s acoustic behavior. The rotor-self noise and the rotor–stator interaction were identified as primary tonal sound sources, along with the highest broadband noise sources located on the rotor. Based on engineering experience, a first acoustic improvement treatment was also quantified with a sound power level reduction of 4 dB(A). In conclusion, the presented method is a beneficial first measurement campaign to quantify the acoustic properties of an electric ducted fan unit under minimal resources in a reasonable time of several weeks when starting from scratch.
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Jie Zhu, Jiangtao Yu, Yingcheng Wu, Yanhong Chao, Peiwen Wu, Linjie Lu, Linlin Chen, Jing He, and Wenshuai Zhu
- Green Chemical Engineering, Vol 4, Iss 1, Pp 73-80 (2023)
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3D printing, Direct ink writing, Ceramic slurry, Kaolin, Adsorption, Chemical engineering, TP155-156, Biochemistry, and QD415-436
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The construction of rapid prototyping for structured ceramics has a promoting effect on potential applications. In this work, engineering slurry with different formulations were used to develop aqueous colloidal ceramic slurry for direct ink writing (DIW). Optimized slurry of Formulation 5 possessed good printing effect for DIW with stable mechanical properties. Related characteristics, including shrinkage, compressive strength, rheological behavior, and chemical property, were also examined. DIW ceramics prepared from optimized slurry can be preliminarily applied to adsorption of Rhodamine B and chlortetracycline, and possessed the advantages of easy separation and operation compared with powder adsorbents. This work provides a strategy for the design of 3D-printed kaolin ceramic slurry, and also extends to potential application in adsorption.
- Full text View record in DOAJ
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You-Lei Fu, Ruoqi Dai, Xiaoshun Xie, and Wu Song
- Heliyon, Vol 9, Iss 3, Pp e13624- (2023)
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Prototype intervention, Usability testing, sEMG, Supine sitting posture, Comfort perception, Science (General), Q1-390, Social sciences (General), and H1-99
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Employees who work long hours frequently complain of muscle fatigue caused by prolonged sitting. As a result, products that assist them when resting in a chair in a reclining position, in order to relieve fatigue and improve comfort are required. To ensure that the new product works as intended, a usability test based on prototyping must be developed. The research process was divided into three stages: firstly, the development of the perception assessment questionnaire; secondly, a validated factor analysis (CFA) was conducted on the perception assessment data of 26 subjects and the measurement model was fitted to verify the reliability and validity of the questionnaire; finally, the sEMG technique was used to verify the comfort level of 21 subjects. Based on usability experiments and an exploration of human factor relationships, this study develops a prototype testing model, which focuses on the comfort perception of body parts, as a means of promoting innovation in the design and manufacturing industry.
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83. How can a foundation be outlined for a successful serious game to increase reading engagement [2023]
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Thomas Bjørner, Mads Strømberg Petersen, Niklas Lee Skjold Hansen, Gustav Jakobsen, and Daniel Hendriksen
- International Journal of Serious Games, Vol 10, Iss 1 (2023)
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Reading engagement, Narrative engagement, Evaluation, Serious Games, Game design, user engagement, Education, Electronic computers. Computer science, QA75.5-76.95, Computer software, and QA76.75-76.765
- Abstract
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This study aims to support a mandatory reading of a novella for high school students by a serious game. The study includes 41 students. The first class is included in the experimental study, which uses a serious game to read the novella. The second class served as the control group and engaged only in analog reading. The evaluation is based on a questionnaire with reading, user, and narrative engagement items. Furthermore, the assessment consists of in-depth interviews with teachers and students. The findings positively affected students’ engagement in the experimental group. Primarily focused attention and reward are higher in the experimental group. However, there was no difference in the narrative engagement between the two groups, indicating that the story (digital or not) is well explained. The qualitative findings revealed positive comments, especially for the reading engagement and the story world. The novelty in this study is the outlined game design process, guided by elements in the foundation, game design, prototyping, and implementation. For the game design, we outlined how to transform the principles from Sweetser and Wyeth to applied design implementations. An important aspect was to illustrate the protagonist with schizophrenia.
- Full text View record in DOAJ
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Ankita M Mohite, Lalita G Nanjannawar, Jiwanasha M Agrawal, Sangamesh Fulari, Shraddha Shetti, Vishwal Kagi, Amol Shirkande, and Sanjivani Gofane
- Journal of Clinical and Diagnostic Research, Vol 17, Iss 3, Pp ZC01-ZC05 (2023)
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digital orthodontics, stereolithography, three-dimensional printing, and Medicine
- Abstract
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Introduction: The digitalisation of dental models has made significant contribution to the current success of orthodontic practices. Rapid Prototyping (RP) is an innovative method of producing physical objects based on Computer-Aided Design (CAD) Computer-Aided Manufacturing (CAM). Aim: To compare the accuracy of the Three-Dimensional (3D) printed rapid prototyped models with orthodontic stone models across different ranges of crowding. Materials and Methods: A cross-sectional study carried out at the Bharati Vidyapeeth Deemed to be University, Dental College and Hospital, Sangli, Maharashtra, India during September 2019 to September 2020. A total of 36 rapid prototyped models were reconstructed from stone models using Light Emitting Diode (LED) scanner and Digital Light Processing (DLP) technology. Dental stone models and RP models were evaluated using digital caliper for different linear measurements and arch dimensions. The data was analysed using Statistical Package for Social Sciences (SPSS) version 26.0. To evaluate accuracy, t-test analyses and Bland-Altman plotting were performed. Results: T-test showed statistically non significant difference in all parameters of measurements of RP models when compared to stone models. According to Bland-Altman plotting. The mean difference between stone and RP models for the various degree of crowding was minimal and within ±0.07 mm in all planes. Conclusion: Discrepancy between dental plaster models and RP models were less than 0.5 mm which was considered clinically non significant. Suggesting that RP models can be effectively used as an alternative to stone models.
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Christina Myers, Lara Piccolo, and Trevor Collins
- Journal of Learning for Development, Vol 10, Iss 1 (2023)
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Theory and practice of education and LB5-3640
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Digital games can be used as educational tools for tackling structural inequalities and promoting social justice. Designing games with these purposes is often a complex task that requires a myriad of combined expertise, including games’ mechanics, software development, educational game design, pedagogy, and knowledge of the educational topic (which can target very specific social issues). Democratising the design of educational games is used to increase the agency and participation of diverse and novice groups throughout design processes - and can be used to improve the efficiency of such games as it directly leads to the inclusion of broad voices, knowledge, experiences and perspectives. This research adopted a Design-Based Research methodology to create, evaluate and validate 13 design principles to democratise the design of educational games for social change. Three research phases were implemented in turn: a preliminary research, prototyping and evaluation phase. The preliminary research phase was based on creating these principles by grounding them on fundamentals of Critical Pedagogy, a theory of education which presents pedagogical techniques to accelerate learning, engagement and social change. The prototyping phase was based on conducting semi-structured interviews to assess and improve these principles with educational and game design experts. During the evaluation phase, these principles were applied and evaluated during two weekend-long game design events, which were mostly attended by diverse groups who had never designed a digital game before. This research presents theoretical and practical contributions related to how to democratise educational game design for social change. It evidenced the relevance of facilitating design principles that addresses what could be done to trigger learning in games by presenting design principles; why this learning could be facilitated, from both educational and gaming perspectives; and how to implement these principles into an educational game.
- Full text View record in DOAJ
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Weison Lin, Yajun Zhu, and Tughrul Arslan
- Journal of Low Power Electronics and Applications, Vol 13, Iss 21, p 21 (2023)
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edge AI accelerator, CNN, dynamic reconfiguration, fault tolerance, Applications of electric power, and TK4001-4102
- Abstract
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Edge AI accelerators are utilized to accelerate the computation in edge AI devices such as image recognition sensors on robotics, door lockers, drones, and remote sensing satellites. Instead of using a general-purpose processor (GPP) or graphic processing unit (GPU), an edge AI accelerator brings a customized design to meet the requirements of the edge environment. The requirements include real-time processing, low-power consumption, and resource-awareness, including resources on field programmable gate array (FPGA) or limited application-specific integrated circuit (ASIC) area. The system’s reliability (e.g., permanent fault tolerance) is essential if the devices target radiation fields such as space and nuclear power stations. This paper proposes a dynamic reconfigurable column streaming-based convolution engine (DycSe) with programmable adder modules for low-power and resource-aware edge AI accelerators to meet the requirements. The proposed DycSe design does not target the FPGA platform only. Instead, it is an intellectual property (IP) core design. The FPGA platform used in this paper is for prototyping the design evaluation. This paper uses the Vivado synthesis tool to evaluate the power consumption and resource usage of DycSe. Since the synthesis tool is limited to giving the final complete system result in the designing stage, we compare DycSe to a commercial edge AI accelerator for cross-reference with other state-of-the-art works. The commercial architecture shares the competitive performance within the low-power ultra-small (LPUS) edge AI scopes. The result shows that DycSe contains 3.56% less power consumption and slight resources (1%) overhead with reconfigurable flexibility.
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Hamdi Selmi, Jean Brousseau, Gabriel Caron-Guillemette, Stéphane Goulet, Jacques Desjardins, and Claude Belzile
- Journal of Manufacturing and Materials Processing, Vol 7, Iss 71, p 71 (2023)
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additive manufacturing, gas metal arc welding, mechanical proprieties, stainless steel, Production capacity. Manufacturing capacity, and T58.7-58.8
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The processes of metal additive manufacturing (AM) are no longer confined to rapid prototyping applications and are seeing increasing use in many fields for the production of tools and finished products. The ability to design parts with practically zero waste, high precision, complex geometry, and on-demand fabrication are among the advantages of this manufacturing approach. One of the drawbacks of this technique is the productivity rate, as the parts are made layer by layer, which also increases the production cost. Moreover, even the working space is limited, especially for the powder bed fusion technique. In view of these disadvantages and in order to guarantee the profitability of this process, it should be oriented to the production of complex components that have a limited volume with a design adapted to additive manufacturing. One solution with which to circumvent these drawbacks is to combine the 3D printing process with conventional manufacturing processes. When designing products, one may choose to use additive manufacturing to create locally complex parts and assemble them with parts produced by conventional processes. On the other hand, and due to the limited AM printing chamber space, it may be necessary to print large parts in multiple smaller parts and then assemble them. In order to investigate the weldability of stainless steel 316L parts produced by laser powder bed fusion (L-PBF), the mechanical behavior of different welding assemblies is tested. Five configurations are studied: non-welded AM specimens, two AM parts welded together, one AM part and one laser cut part welded together, two laser-cut parts welded together, and non-welded laser cut specimens. Welding is performed using the Pulsed Gas Metal Arc Welding process (GMAW-P). Specimen strength is assessed through static and fatigue tests. The results demonstrate that 316L AM parts are weldable, and the tensile and fatigue properties of L-PBF 316L welded components and welded laser cut components are comparable. GMAW-P welding led to lower fatigue results for AM components than for other configurations, but the difference is not important. It was observed that welding defects may have a direct impact on mechanical properties.
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Shashi Kant Shankar, Adolfo Ruiz-Calleja, Luis P. Prieto, María Jesús Rodríguez-Triana, Pankaj Chejara, and Sandesh Tripathi
- Journal of Universal Computer Science, Vol 29, Iss 3, Pp 265-297 (2023)
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ad-hoc development, reusability, Separation of Con, Electronic computers. Computer science, and QA75.5-76.95
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Multimodal Learning Analytics (MMLA) solutions aim to provide a more holistic picture of a learning situation by processing multimodal educational data. Considering contextual information of a learning situation is known to help in providing more relevant outputs to educational stakeholders. However, most of the MMLA solutions are still in prototyping phase and dealing with different dimensions of an authentic MMLA situation that involve multiple cross-disciplinary stakeholders like teachers, researchers, and developers. One of the reasons behind still being in prototyping phase of the development lifecycle is related to the challenges that software developers face at different levels in developing context-aware MMLA solutions. In this paper, we identify the requirements and propose a data infrastructure called CIMLA. It includes different data processing components following a standard data processing pipeline and considers contextual information following a data structure. It has been evaluated in three authentic MMLA scenarios involving different cross-disciplinary stakeholders following the Software Architecture Analysis Method. Its fitness was analyzed in each of the three scenarios and developers were interviewed to assess whether it meets functional and non-functional requirements. Results showed that CIMLA supports modularity in developing context-aware MMLA solutions and each of its modules can be reused with required modifications in the development of other solutions. In the future, the current involvement of a developer in customizing the configuration file to consider contextual information can be investigated.
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Istiva Depiyahani and Fajriah Azra
- Jurnal Pijar MIPA (Pengkajian Ilmu dan Pengajaran Matematika dan Ilmu Pengetahuan Alam), Vol 18, Iss 2, Pp 194-200 (2023)
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application, learning media, android, mole concept, Science (General), Q1-390, Education (General), and L7-991
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This study aims to develop a product in the form of an Android-based learning media application based on the mole concept material for class X SMA/MA that is valid and practical. The study uses the Plomp development research model, which consists of three steps: preliminary research, prototyping phase, and assessment phase. This research is limited to the prototyping phase for the practicality stage of the small group evaluation. Three chemistry lecturers carried out the product validity test at the Faculty of Mathematics and Natural Sciences, Padang State University, two Al-istiqamah High School chemistry teachers as material experts, and two lecturers of informatics engineering at Padang State University as media experts. Fifteen students and two chemistry teachers carried out the practicality test. The validity data analysis technique uses Aiken's V index. The validity test results showed that the Android-based learning media application developed belongs to the valid category with an average V value of 0.86 for material experts and an average V value of 0.93 for media experts. The practicality data analysis technique uses a percentage formula. The results of the practicality test in small groups are classified as "very practical," with a practicality percentage value of 90% for students' practicality and a practicality percentage value of 92% for teachers' practicality. Based on the results of the validation and practicality tests, it was found that applying android-based learning media to the mole concept material was valid and practical.
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Lilis Dahlianis and Iswendi Iswendi
- Jurnal Pijar MIPA (Pengkajian Ilmu dan Pengajaran Matematika dan Ilmu Pengetahuan Alam), Vol 18, Iss 2, Pp 231-236 (2023)
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chemistry uno cards, learning media, chemical bonds, Science (General), Q1-390, Education (General), and L7-991
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This study aims to develop chemical uno cards as learning media in class X senior high school in chemical bonding materials that are valid and practical. This type of research is development research using the Plomp model. This research has three stages, namely (1) preliminary research, (2) prototyping stage, and (3) assessment phase. The subjects of this research consist of 5 chemistry lecturers at the Faculty of Mathematics and Science, Padang State University, two chemistry teachers, and 12 students at SMA N 13 Padang for the 2021/2022 academic year. The research instruments used were self-evaluation sheets, one-to-one evaluation interview sheets, content validity questionnaires, construct media, and practicality questionnaires. Data analysis for validity uses Aiken's V formula, and practicality uses the percentage formula. The research results obtained a V value for material validation of 0.92 and media validation of 0.92, which are included in the valid category. The media practicality was obtained from the teacher's response of 96.8% and 94.4% of the students included in the very practical category.
- Full text View record in DOAJ
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Jan-Erik Rath, Robert Graupner, and Thorsten Schüppstuhl
- Machines, Vol 11, Iss 365, p 365 (2023)
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fiber-reinforced plastic, composite, dieless forming, incremental forming, robotics, automation, Mechanical engineering and machinery, and TJ1-1570
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The demand for lightweight materials, such as fiber-reinforced plastics (FRP), is constantly growing. However, current FRP production mostly relies on expensive molds representing the final part geometry, which is not economical for prototyping or highly individualized products, such as in the medical or sporting goods sector. Therefore, inspired by incremental sheet metal forming, we conduct a systematic functional analysis on new processing methods for shaping woven FRP without the use of molds. Considering different material combinations, such as dry fabric with thermoset resin, thermoset prepreg, thermoplastic commingled yarn weave and organo sheets, we propose potential technical implementations of novel dieless forming techniques, making use of simple robot-guided standard tools, such as hemispherical tool tips or rollers. Feasibility of selected approaches is investigated in basic practical experiments with handheld tools. Results show that the main challenge of dieless local forming, the conservation of already formed shapes while allowing drapability of remaining areas, is best fulfilled by local impregnation, consolidation and solidification of commingled yarn fabric, as well as concurrent forming of prepreg and metal wire mesh support material. Further research is proposed to improve part quality.
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Cecilia Goracci, Jovana Juloski, Claudio D’Amico, Dario Balestra, Alessandra Volpe, Jelena Juloski, and Alessandro Vichi
- Materials, Vol 16, Iss 2166, p 2166 (2023)
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3D printing, additive manufacturing, rapid prototyping, orthodontics, materials, review, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, and QC120-168.85
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The review aimed at analyzing the evidence available on 3D printable materials and techniques used for the fabrication of orthodontic appliances, focusing on materials properties that are clinically relevant. MEDLINE/PubMed, Scopus, and Cochrane Library databases were searched. Starting from an initial retrieval of 669 citations, 47 articles were finally included in the qualitative review. Several articles presented proof-of-concept clinical cases describing the digital workflow to manufacture a variety of appliances. Clinical studies other than these case reports are not available. The fabrication of aligners is the most investigated application of 3D printing in orthodontics, and, among materials, Dental LT Clear Resin (Formlabs) has been tested in several studies, although Tera Harz TC-85 (Graphy) is currently the only material specifically marketed for direct printing of aligners. Tests of the mechanical properties of aligners materials lacked homogeneity in the protocols, while biocompatibility tests failed to assess the influence of intraoral conditions on eluents release. The aesthetic properties of 3D-printed appliances are largely unexplored. The evidence on 3D-printed metallic appliances is also limited. The scientific evidence on 3D printable orthodontic materials and techniques should be strengthened by defining international standards for laboratory testing and by starting the necessary clinical trials.
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Agnė Butkutė, Tomas Jurkšas, Tomas Baravykas, Bettina Leber, Greta Merkininkaitė, Rugilė Žilėnaitė, Deividas Čereška, Aiste Gulla, Mindaugas Kvietkauskas, Kristina Marcinkevičiūtė, Peter Schemmer, and Kęstutis Strupas
- Materials, Vol 16, Iss 2174, p 2174 (2023)
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selective laser etching, 3D laser microfabrication, laser welding, glass microfluidics, femtosecond laser microprocessing, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, and QC120-168.85
- Abstract
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Nowadays, lab-on-chip (LOC) devices are attracting more and more attention since they show vast prospects for various biomedical applications. Usually, an LOC is a small device that serves a single laboratory function. LOCs show massive potential for organ-on-chip (OOC) device manufacturing since they could allow for research on the avoidance of various diseases or the avoidance of drug testing on animals or humans. However, this technology is still under development. The dominant technique for the fabrication of such devices is molding, which is very attractive and efficient for mass production, but has many drawbacks for prototyping. This article suggests a femtosecond laser microprocessing technique for the prototyping of an OOC-type device—a liver-on-chip. We demonstrate the production of liver-on-chip devices out of glass by using femtosecond laser-based selective laser etching (SLE) and laser welding techniques. The fabricated device was tested with HepG2(GS) liver cancer cells. During the test, HepG2(GS) cells proliferated in the chip, thus showing the potential of the suggested technique for further OOC development.
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Mert Gülçür, Paul Wilson, Michael Donnelly, Kevin Couling, Vannessa Goodship, Jérôme Charmet, Mark A. Williams, and Gregory Gibbons
- Materials & Design, Vol 227, Iss , Pp 111741- (2023)
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X-ray, X-ray computed tomography, Micro-injection moulding, 3D visualisation, Injection moulding, Rapid prototyping, Materials of engineering and construction. Mechanics of materials, and TA401-492
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This work presents X-ray computed tomography (XCT) as a dimensional quality assurance technique for micro-injection moulded polymeric test objects for the establishment of predictive quality models and quantifying soft-tool deformation. The results are compared against an industry standard laser-scanning-confocal microscope (LSCM) for the evaluation of XCT’s capability. The work demonstrates; (i) the exploitation of a XCT equipment for dimensional characterisation of micro-injection moulded products made out of polymers with adequate acquisition times, (ii) that acquired XCT data from the 3D visualisation of the micromouldings perform on par with a laser-scanning-confocal microscope in a quality prediction model, (iii) that the deformation occurring in an additively manufactured soft-tool can be quantified using XCT. The technique was particularly superior in volumetric data acquisition compared to LSCM in the filling prediction of the micromouldings. Better accuracy and repeatability in predicting the quality of the mouldings up to 92% achieved with XCT, in conjunction with an in-line collected soft-tool surface temperature data as an indirect quality assurance method. Given the capability of the XCT for the 3D data acquisition of polymeric miniature components, the approach described here has great potential in high-value micro-manufacturing process quality modelling for in-line quality assessment of miniature and added value products in data-rich contexts.Rendered 3D animation of the X-ray CT data: https://youtu.be/KwZty_yoDfs.
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95. Established and Emerging Methods for Protecting Linear DNA in Cell-Free Expression Systems [2023]
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Trevor J. Fochtman and Javin P. Oza
- Methods and Protocols, Vol 6, Iss 36, p 36 (2023)
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cell-free protein synthesis, linear expression templates, LETs, exonuclease, recBCD, GamS, Biology (General), and QH301-705.5
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Cell-free protein synthesis (CFPS) is a method utilized for producing proteins without the limits of cell viability. The plug-and-play utility of CFPS is a key advantage over traditional plasmid-based expression systems and is foundational to the potential of this biotechnology. A key limitation of CFPS is the varying stability of DNA types, limiting the effectiveness of cell-free protein synthesis reactions. Researchers generally rely on plasmid DNA for its ability to support robust protein expression in vitro. However, the overhead required to clone, propagate, and purify plasmids reduces the potential of CFPS for rapid prototyping. While linear templates overcome the limits of plasmid DNA preparation, linear expression templates (LETs) were under-utilized due to their rapid degradation in extract based CFPS systems, limiting protein synthesis. To reach the potential of CFPS using LETs, researchers have made notable progress toward protection and stabilization of linear templates throughout the reaction. The current advancements range from modular solutions, such as supplementing nuclease inhibitors and genome engineering to produce strains lacking nuclease activity. Effective application of LET protection techniques improves expression yields of target proteins to match that of plasmid-based expression. The outcome of LET utilization in CFPS is rapid design–build–test–learn cycles to support synthetic biology applications. This review describes the various protection mechanisms for linear expression templates, methodological insights for implementation, and proposals for continued efforts that may further advance the field.
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Yuanyuan Wei, Tianle Wang, Yuye Wang, Shuwen Zeng, Yi-Ping Ho, and Ho-Pui Ho
- Micromachines, Vol 14, Iss 656, p 656 (2023)
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microfluidics, laser ablation, thermal bonding, Mechanical engineering and machinery, and TJ1-1570
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In this paper, we report a simple, rapid, low-cost, biocompatible, and detachable microfluidic chip fabrication method for customized designs based on Parafilm®. Here, Parafilm® works as both a bonding agent and a functional membrane. Its high ultimate tensile stress (3.94 MPa) allows the demonstration of high-performance actuators such as microvalves and micropumps. By laser ablation and the one-step bonding of multiple layers, 3D structured microfluidic chips were successfully fabricated within 2 h. The consumption time of this method (~2 h) was 12 times less than conventional photolithography (~24 h). Moreover, the shear stress of the PMMA–Parafilm®–PMMA specimens (0.24 MPa) was 2.13 times higher than that of the PDMS–PDMS specimens (0.08 MPa), and 0.56 times higher than that of the PDMS–Glass specimens (0.16 MPa), showing better stability and reliability. In this method, multiple easily accessible materials such as polymethylmethacrylate (PMMA), PVC, and glass slides were demonstrated and well-incorporated as our substrates. Practical actuation devices that required high bonding strength including microvalves and micropumps were fabricated by this method with high performance. Moreover, the biocompatibility of the Parafilm®-based microfluidic devices was validated through a seven-day E. coli cultivation. This reported fabrication scheme will provide a versatile platform for biochemical applications and point-of-care diagnostics.
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Elise Hodson, Teija Vainio, Michel Nader Sayún, Martin Tomitsch, Ana Jones, Meri Jalonen, Ahmet Börütecene, Md Tanvir Hasan, Irina Paraschivoiu, Annika Wolff, Sharon Yavo-Ayalon, Sari Yli-Kauhaluoma, and Gareth W. Young
- Multimodal Technologies and Interaction, Vol 7, Iss 33, p 33 (2023)
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smart city, social impact, evaluation, engagement, social sustainability, citizens, Technology, and Science
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This study examines motivations, definitions, methods and challenges of evaluating the social impacts of smart city technologies and services. It outlines concepts of social impact assessment and discusses how social impact has been included in smart city evaluation frameworks. Thematic analysis is used to investigate how social impact is addressed in eight smart city projects that prioritise human-centred design across a variety of contexts and development phases, from design research and prototyping to completed and speculative projects. These projects are notable for their emphasis on human, organisational and natural stakeholders; inclusion, participation and empowerment; new methods of citizen engagement; and relationships between sustainability and social impact. At the same time, there are gaps in the evaluation of social impact in both the smart city indexes and the eight projects. Based on our analysis, we contend that more coherent, consistent and analytical approaches are needed to build narratives of change and to comprehend impacts before, during and after smart city projects. We propose criteria for social impact evaluation in smart cities and identify new directions for research. This is of interest for smart city developers, researchers, funders and policymakers establishing protocols and frameworks for evaluation, particularly as smart city concepts and complex technologies evolve in the context of equitable and sustainable development.
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Cristina Sanchez, Laura Blanco, Carmina del Río, Eloy Urendes, Vanina Costa, and Rafael Raya
- PeerJ, Vol 11, p e15095 (2023)
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3D printing, Children, Electromyography, Motor disorders, Passive exoskeleton, Upper limb, and Medicine
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The rehabilitation of children with motor disorders is mainly focused on physical interventions. Numerous studies have demonstrated the benefits of upper function using robotic exoskeletons. However, there is still a gap between research and clinical practice, owing to the cost and complexity of these devices. This study presents a proof of concept of a 3D-printed exoskeleton for the upper limb, following a design that replicates the main characteristics of other effective exoskeletons described in the literature. 3D printing enables rapid prototyping, low cost, and easy adjustment to the patient anthropometry. The 3D-printed exoskeleton, called POWERUP, assists the user’s movement by reducing the effect of gravity, thereby allowing them to perform upper limb exercises. To validate the design, this study performed an electromyography-based assessment of the assistive performance of POWERUP, focusing on the muscular response of both the biceps and triceps during elbow flexion–extension movements in 11 healthy children. The Muscle Activity Distribution (MAD) is the proposed metric for the assessment. The results show that (1) the exoskeleton correctly assists elbow flexion, and (2) the proposed metric easily identifies the exoskeleton configuration: statistically significant differences (p-value = 2.26 ⋅ 10−7 < 0.001) and a large effect size (Cohen’s d = 3.78 > 0.8) in the mean MAD value were identified for both the biceps and triceps when comparing the transparent mode (no assistance provided) with the assistive mode (anti-gravity effect). Therefore, this metric was proposed as a method for assessing the assistive performance of exoskeletons. Further research is required to determine its usefulness for both the evaluation of selective motor control (SMC) and the impact of robot-assisted therapies.
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Katarzyna Bulanda, Mariusz Oleksy, and Rafał Oliwa
- Polymers, Vol 15, Iss 1565, p 1565 (2023)
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MEM, blends, hybrid materials, additive manufacturing, design, Organic chemistry, and QD241-441
- Abstract
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As part of this work, polymer composites based on polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) were obtained and used in 3D printing technology, particularly Melted Extrusion Modeling (MEM) technology. The influence of selected fillers on the properties of the obtained composites was investigated. For this purpose, modified fillers such as silica modified with alumina, bentonite modified with a quaternary ammonium salt, and hybrid lignin/silicon dioxide filler were introduced into the PC/ABS matrix. In the first part of this work, polymer blends and their composites containing 1.5–3 wt. of the filler were used to obtain the filament using the proprietary technological line. Moldings for testing the performance properties were obtained using additive manufacturing techniques and injection molding. In the subsequent part of this work, rheological properties (mass flow rate (MFR) and viscosity curves) and mechanical properties (Rockwell hardness and static tensile strength with Young’s modulus) were examined. The structures of the obtained composites were also determined by scanning electron microscopy (SEM/EDS). The obtained results confirmed the results obtained from a wide-angle X-ray scattering analysis (WAXS). In turn, the physicochemical properties were characterized on the basis of the results of tests using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Based on the obtained results, it was found that the introduced modified additives had a significant impact on the processing and functional properties of the tested composites.
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Fedor Doronin, Georgy Rytikov, Andrey Evdokimov, Yury Rudyak, Irina Taranets, and Victor Nazarov
- Processes, Vol 11, Iss 774, p 774 (2023)
- Subjects
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LDPE, PET, adhesion, additive manufacturing, electro-induced multi-gas treatment, free surface energy, Chemical technology, TP1-1185, Chemistry, and QD1-999
- Abstract
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We investigated the effect of electro-induced multi-gas modification (EIMGM) duration on the adhesion and wear resistance of PET and LDPE polymer substrates used in the printing industry. It was found that EIMGM increases the polar component and the complete free surface energy from 26 to 57 mJ/m2 for LDPE and from 37 to 67 mJ/m2 for PET (due to the formation of oxygen-containing groups on the surface of the materials). Although the degree of textural and morphological heterogeneity of the modified LDPE increased more than twice compared to the initial state, it is not still suitable for application as a substrate in extrusion 3D printing. However, for PET, the plasma-chemical modification contributed to a significant increase (~5 times) in filament adhesion to its surface (due to chemical and morphological transformations of the surface layers) which allows for using the FFF technology for additive prototyping on the modified PET-substrates.
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