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1. 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
- Abstract
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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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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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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
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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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Tayyaba Sahar, Muhammad Rauf, Ahmar Murtaza, Lehar Asip Khan, Hasan Ayub, Syed Muslim Jameel, and Inam Ul Ahad
- Results in Engineering, Vol 17, Iss , Pp 100803- (2023)
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Metal additive manufacturing (MAM), Laser powder bed fusion (L-PBF), Machine learning (ML), Process parameter optimization, Anomaly detection, and Technology
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Metal Additive Manufacturing (MAM) applications are growing rapidly in high-tech industries such as biomedical and aerospace, and in many other industries including tooling, casting, automotive, oil and gas for production and prototyping. The onset of Laser Powder Bed Fusion (L-PBF) technology proved to be an efficient technique that can convert metal additive manufacturing into a reformed process if anomalies occurred during this process are eliminated. Industrial applications demand high accuracy and risk-free products whereas prototyping using MAM demand lower process and product development time. In order to address these challenges, Machine Learning (ML) experts and researchers are trying to adopt an efficient method for anomaly detection in L-PBF so that the MAM process can be optimized and desired final part properties can be achieved. This review provides an overview of L-PBF and outlines the ML methods used for anomaly detection in L-PBF. The paper also explains how ML methods are being used as a step forward toward enabling the real-time process control of MAM and the process can be optimized for higher accuracy, lower production time, and less material waste. Authors have a strong believe that ML techniques can reform MAM process, whereas research concerned to the anomaly detection using ML techniques is limited and needs attention.This review has been done with a hope that ML experts can easily find a direction and contribute in this field.
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5. Design and prototyping of a robotic hand for sign language using locally-sourced materials [2023]
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Ibrahim A. Adeyanju, Sheriffdeen O. Alabi, Adebimpe O. Esan, Bolaji A. Omodunbi, Oluwaseyi O. Bello, and Samuel Fanijo
- Scientific African, Vol 19, Iss , Pp e01533- (2023)
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Android, Communication, Deaf, Disability, Dumb, Hardware, and Science
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People living with disability constitute a significant percentage of the world population. For many people with disabilities, assistance and support are prerequisites for participating in societal activities. This research work developed a hardware prototype of a robotic hand forfor sign language communication with persons living with hard-of-hearing disabilities (deaf and/or dumb). The prototype has three basic modules: the input unit, the control unit, and the robotic hand. The input unit is designed as an Android-based mobile application with speech recognition capabilities while the control unit is ATMEGA 2560 microcontroller board. The robotic hand is constructed using locally available materials (bathroom Slippers, expandable rubber, straw pipe, and tiny rope) together with three servo motors and is designed to look and perform movements similar to a human hand. The prototype was evaluated quantitatively in terms of empirical accuracy and response time. It was also evaluated qualitatively by thirty-five (35) users which included fifteen (15) experience ASL users, eighteen (18) non-experience ASL users, and two (2) ASL experts, who completed questionnaires to rate the prototype on a 5-point Likert scale in terms of five parameters: functionality, reliability, ease of use, efficiency, and portability. An accuracy of 78.43% with an average response time of 2 s was obtained from empirical experiments. Statistical analysis of user responses showed that 97%, 68%, 77%, 80%, and 83% of users rated the system as above average for functionality, reliability, ease of use, efficiency, and portability, respectively. The robotic hand effectively communicates American Sign Language which includes English Alphabets, numbers (1–9), and some selected common words, which can be demonstrated with a single hand for hard of hearing persons. To the best of our knowledge, this work is the first ASL robotic hand that is based on locally sourced cost-effective materials, and we build on flaws from existing literature, most of which are either template-based, not real-time, or expensive. In terms of future work, the prototype can be improved by extending the single robotic hand to a fully robotic body with two hands.
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Simon Orlob, Christoph Hobisch, Johannes Wittig, Daniel Auinger, Otto Touzil, Gabriel Honnef, Otmar Schindler, Philipp Metnitz, Georg Feigl, and Gerhard Prause
- Data in Brief, Vol 46, Iss , Pp 108767- (2023)
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cardiopulmonary resuscitation, Mechanical ventilation, Mechanical chest-compression, Respiratory monitoring, Thiel embalmed cadaver, Biomechanics, Computer applications to medicine. Medical informatics, R858-859.7, Science (General), and Q1-390
- Abstract
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The data presented in this article relate to the research article, “Reliability of mechanical ventilation during continuous chest compressions: a crossover study of transport ventilators in a human cadaver model of CPR” [1].This article contains raw data of continuous recordings of airflow, airway and esophageal pressure during the whole experiment. Data of mechanical ventilation was obtained under ongoing chest compressions and from repetitive measurements of pressure-volume curves. All signals are presented as raw time series data with a sample rate of 200Hz for flow and 500 Hz for pressure. Additionally, we hereby publish extracted time series recordings of force and compression depth from the used automated chest compression device. Concomitantly, we report tables with time stamps from our laboratory book by which the data can be sequenced into different phases of the study protocol.We also present a dataset of derived volumes which was used for statistical analysis in our research article together with the used exclusion list.The reported dataset can help to understand mechanical properties of Thiel-embalmed cadavers better and compare different models of cardiopulmonary resuscitation (CPR). Future research may use this data to translate our findings from bench to bedside. Our recordings may become useful in developing respiratory monitors for CPR, especially in prototyping and testing algorithms of such devices.
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Jonathan Silcock, Iuri Marques, Janice Olaniyan, David K. Raynor, Helen Baxter, Nicky Gray, Syed T. R. Zaidi, George Peat, Beth Fylan, Liz Breen, Jonathan Benn, and David P. Alldred
- Health Expectations, Vol 26, Iss 1, Pp 399-408 (2023)
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aged, deprescribing, frailty, polypharmacy, primary health care, referral and consultation, Medicine (General), R5-920, Public aspects of medicine, and RA1-1270
- Abstract
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Abstract Background In older people living with frailty, polypharmacy can lead to preventable harm like adverse drug reactions and hospitalization. Deprescribing is a strategy to reduce problematic polypharmacy. All stakeholders should be actively involved in developing a person‐centred deprescribing process that involves shared decision‐making. Objective To co‐design an intervention, supported by a logic model, to increase the engagement of older people living with frailty in the process of deprescribing. Design Experience‐based co‐design is an approach to service improvement, which uses service users and providers to identify problems and design solutions. This was used to create a person‐centred intervention with the potential to improve the quality and outcomes of the deprescribing process. A ‘trigger film’ showing older people talking about their healthcare experiences was created and facilitated discussions about current problems in the deprescribing process. Problems were then prioritized and appropriate solutions were developed. The review located the solutions in the context of current processes and procedures. An ideal care pathway and a complex intervention to deliver better care were developed. Setting and Participants Older people living with frailty, their informal carers and professionals living and/or working in West Yorkshire, England, UK. Deprescribing was considered in the context of primary care. Results The current deprescribing process differed from an ideal pathway. A complex intervention containing seven elements was required to move towards the ideal pathway. Three of these elements were prototyped and four still need development. The complex intervention responded to priorities about (a) clarity for older people about what was happening at all stages in the deprescribing process and (b) the quality of one‐to‐one consultations. Conclusions Priorities for improving the current deprescribing process were successfully identified. Solutions were developed and structured as a complex intervention. Further work is underway to (a) complete the prototyping of the intervention and (b) conduct feasibility testing. Patient or Public Contribution Older people living with frailty (and their informal carers) have made a central contribution, as collaborators, to ensure that a complex intervention has the greatest possible potential to enhance the experience of deprescribing medicines.
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Russell Galea, Pierre-Sandre Farrugia, Krzysztof K. Dudek, Daphne Attard, Joseph N. Grima, and Ruben Gatt
- Materials & Design, Vol 226, Iss , Pp 111596- (2023)
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Perforations, Subtractive manufacturing, Negative Poisson’s ratio, 3D auxetic structures, Materials of engineering and construction. Mechanics of materials, and TA401-492
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Prototyping of three-dimensional mechanical metamaterials that exhibit negative Poisson’s ratio is usually performed through additive manufacturing. Although this technique has a huge potential, its use to engineer mechanical metamaterials for consumer products is still challenging. In this work, a novel design method is being proposed where 3D auxetic metamaterials can be produced by introducing continuous voids of constant cross-sectional area. Such voids would be inserted at strategic positions in different perpendicular planes of a solid block to obtain a continuous three-dimensional mechanical metamaterial that can exhibit the desired mechanical characteristics. The use of continuous voids to design the 3D meatamaterial makes it possible to use additive manufacturing, subtractive manufacturing as well as casting to produce these systems. The proposed design method is explained by using continuous voids having a diamond shaped cross-sectional area. The resulting group of structures can be described as connected polygons and were found to exhibit a negative or zero Poisson’s ratio. The analysed systems were also found to have a strain independent Poisson’s ratio up to at least 7% strain. The proposed design method can thus facilitate the availability of three dimensional auxetic metamaterials in the consumer market which to date is conspicuous by their absence.
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Francesca Usai, Giada Loi, Franca Scocozza, Massimo Bellato, Ignazio Castagliuolo, Michele Conti, and Lorenzo Pasotti
- Materials Today Bio, Vol 18, Iss , Pp 100526- (2023)
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Bioprinting, Engineered living materials, Biosensors, Synthetic biology, Engineered bacteria, Medicine (General), R5-920, Biology (General), and QH301-705.5
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The intertwined adoption of synthetic biology and 3D bioprinting has the potential to improve different application fields by fabricating engineered living materials (ELMs) with unnatural genetically-encoded sense & response capabilities. However, efforts are still needed to streamline the fabrication of sensing ELMs compatible with field use and improving their functional complexity. To investigate these two unmet needs, we adopted a workflow to reproducibly construct bacterial ELMs with synthetic biosensing circuits that provide red pigmentation as visible readout in response to different proof-of-concept chemical inducers. We first fabricated single-input/single-output ELMs and we demonstrated their robust performance in terms of longevity (cell viability and evolutionary stability >15 days, and long-term storage >1 month), sensing in harsh, non-sterile or nutrient-free conditions compatible with field use (soil, water, and clinical samples, including real samples from Pseudomonas aeruginosa infected patients). Then, we fabricated ELMs including multiple spatially-separated biosensor strains to engineer: level-bar materials detecting molecule concentration ranges, multi-input/multi-output devices with multiplexed sensing and information processing capabilities, and materials with cell-cell communication enabling on-demand pattern formation. Overall, we showed successful field use and multiplexed functioning of reproducibly fabricated ELMs, paving the way to a future automation of the prototyping process and boosting applications of such devices as in-situ monitoring tools or easy-to-use sensing kits.
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Huang, Xina, Ding, Shoubin, Lang, Lihui, and Gong, Shuili
- Rapid Prototyping Journal, 2023, Vol. 29, Issue 2, pp. 209-217.
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Ameri, Behnam, Taheri-Behrooz, Fathollah, Majidi, Hamid Reza, and Mohammad Aliha, Mohammad Reza
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 218-231.
12. Modeling SEBM process of tantalum lattices [2023]
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Yue, Mingkai, Li, Meie, An, Ning, Yang, Kun, Wang, Jian, and Zhou, Jinxiong
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 232-245.
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Wang, Xiaoqi, Cao, Jianfu, and Cao, Ye
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 246-258.
14. Force-flow guided reinforcement design of homogeneous mesoscale structure in additive manufacturing [2023]
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Yu, Ying, Huang, Huan, Wang, Shuo, Li, Shuaishuai, and Wang, Yu
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 259-274.
15. Impact energy absorption and fracture mechanism of FFF made fiberglass reinforced polymer composites [2023]
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Prajapati, Ashish R., Dave, Harshit K., and Raval, Harit K.
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 275-287.
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Verma, Virendra Kumar, Kamble, Sachin S., and Ganapathy, L.
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 288-311.
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Panchagnula, Jayaprakash Sharma and Simhambhatla, Suryakumar
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 312-323.
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Riensche, Alex, Severson, Jordan, Yavari, Reza, Piercy, Nicholas L., Cole, Kevin D., and Rao, Prahalada
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 324-343.
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Zhang, Guoquan, Wang, Yaohui, He, Jian, and Xiong, Yi
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 344-353.
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Danielak, Anna, Chauhan, Siddharth Singh, Islam, Aminul, Andrzejewski, Jacek, and Pedersen, David Bue
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 354-365.
21. Evaluation of Cu-Ti dissimilar interface characteristics for wire arc additive manufacturing process [2023]
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Mishra, Avinash, Paul, Amrit Raj, Mukherjee, Manidipto, Singh, Rabesh Kumar, and Sharma, Anuj Kumar
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 366-377.
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Brauer, Cole and Aukes, Daniel
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 378-392.
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Lavecchia, Fulvio, Pellegrini, Alessandro, and Galantucci, Luigi Maria
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 393-407.
24. The development of a radial based integrated network for the modelling of 3D fused deposition [2023]
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AlAlaween, Wafa', Abueed, Omar, Gharaibeh, Belal, Alalawin, Abdallah, Mahfouf, Mahdi, Alsoussi, Ahmad, and Albashabsheh, Nibal
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 2, pp. 408-421.
25. Mechanical properties assessment of a 3D printed composite under torsional and perpendicular stress [2023]
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Lovo, João Fiore Parreira, Gerlin Neto, Vicente, Piedade, Lucas Pereira, Massa, Renan Cesar, Pintão, Carlos Alberto, Foschini, Cesar Renato, and Fortulan, Carlos Alberto
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 1-8.
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Candidori, Sara, Graziosi, Serena, Russo, Paola, Osouli, Kasra, De Gaetano, Francesco, Zanini, Alberto Antonio, and Costantino, Maria Laura
- Rapid Prototyping Journal, 2023, Vol. 29, Issue 11, pp. 7-20.
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Mundada, Piyush Suresh, Yang, Che-Hao, and Chen, Roland K.
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 9-18.
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Mussi, Elisa, Servi, Michaela, Facchini, Flavio, Furferi, Rocco, and Volpe, Yary
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 19-32.
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Verma, Virendra Kumar, Kamble, Sachin S., Ganapathy, L., and Tarei, Pradeep Kumar
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 33-49.
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Yousefi Kanani, Armin, Rennie, Allan E.W., and Abd Rahim, Shayfull Zamree Bin
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 50-66.
31. Ti6Al4V scaffolds fabricated by laser powder bed fusion with hybrid volumetric energy density [2023]
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Gaur, Bhanupratap, Soman, Deepak, Ghyar, Rupesh, and Bhallamudi, Ravi
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 67-79.
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Ettaieb, Kamel, Godineau, Kevin, Lavernhe, Sylvain, and Tournier, Christophe
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 80-91.
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Ali, Shafahat, Abdallah, Said, Devjani, Deepak H., John, Joel S., Samad, Wael A., and Pervaiz, Salman
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 92-111.
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Kaill, Nathaniel, Campbell, Robert, and Pradel, Patrick
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 112-117.
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Xiao, Haifeng, Zhang, Changchun, and Zhu, Haihong
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 118-127.
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Zhao, Donghua, Zhu, Gaohan, He, Jiapeng, and Guo, Weizhong
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 128-144.
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Evans, Emmeline and McComb, Christopher
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 145-156.
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Şirin, Şenol, Aslan, Enes, and Akincioğlu, Gülşah
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 157-165.
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Borra, N. Dhanunjayarao and Neigapula, Venkata Swamy Naidu
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 166-184.
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Seyedzavvar, Mirsadegh and Boğa, Cem
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 1, pp. 185-206.
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Sebastian-Camilo Vanegas-Ayala, Julio Barón-Velandia, and Daniel-David Leal-Lara
- Advances in Fuzzy Systems, Vol 2023 (2023)
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Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Computer software, and QA76.75-76.765
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Establishing the indoor and outdoor humidity values in a greenhouse allows us to describe the crop yield during its entire developmental cycle. This study seeks to develop a predictive model of indoor relative humidity values in a greenhouse with high accuracy and interpretability through the use of optimized fuzzy inference systems, in order to offer greenhouse users a clear and simple description of their behaviour. The three-phase methodology applied made use of descriptive statistics techniques, correlation analysis, and prototyping paradigm for the iterative and incremental development of the predictive model, validated through error measurement. The research resulted in six models which define the behaviour of humidity as a result of temperature, CO2, and soil moisture, with percentages of effectiveness above 90%. The implementation of a Mamdani-type fuzzy inference system, optimized by a hybrid method combining genetic and interior point algorithms, allowed to predict the relative humidity in greenhouses with high interpretability and precision, with an effectiveness percentage of 90.97% and MSE (mean square error) of 8.2e − 3.
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Michela Tramonti, Alden Meirzhanovich Dochshanov, and Assel Sagnayevna Zhumabayeva
- Applied Sciences, Vol 13, Iss 858, p 858 (2023)
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3D printing, Arduino, educational robotics, design thinking, open-source project, open-source platform, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
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The dynamic spread of 3D printing technologies and open-source electronics prototyping platforms has significantly enriched the diversity of instruments used within educational robotics (ER) settings. An active, low-entry-level community offering ready-to-use libraries for a broad variety of devices assists in the development of quite sophisticated projects. However, the flipside of the coin is represented by the current research findings, which reveal that students’ interest in science, technology, engineering and mathematics (STEM) subjects has declined across Europe, as manifested in difficulties when approaching scientific topics and dealing with problems and phenomena studied from a multidisciplinary perspective. Consequently, a significant percentage of youths are at risk of social exclusion due to the direct relationship between low academic achievements and school dropout. Moreover, learners lack guidance in applied and life-context skills, such as creative thinking, problem solving, and collaboration, which highlights the need to introduce innovative pedagogical approaches. In this context, the design thinking (DT) methodology was proposed to tackle the problem. Originating in the development of psychological studies on creativity in the 1950s within the educational context, DT is known to foster creative thinking, help develop empathy, promote action-oriented actions, improve meta-cognitive awareness, contribute to problem-solving skills, and enhance students’ imagination. The last point supports the students’ development of critical thinking, social inclusion, teamwork skills, and academic performance. Thus, this paper introduces a methodological framework combining DT with ER classes. First, to approach the problem, the teachers’ survey data were collected and analysed to reveal the respondents’ level of integration of the DT methodology into current school curricula. Then, the work focused on the application of this framework in a learning experience by addressing the weakest points established and their elaboration through the combined ER and DT classes in the context of secondary schools.
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Vyacheslav Rybin, Timur Karimov, Oleg Bayazitov, Dmitriy Kvitko, Ivan Babkin, Kirill Shirnin, Georgii Kolev, and Denis Butusov
- Applied Sciences, Vol 13, Iss 936, p 936 (2023)
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chaos-based communication, covert transmission, secure communication systems, hardware chaos generators, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
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Chaos-based communications are a promising application of chaos theory and nonlinear dynamics. Their key features include concealed transmission, high security, and native broadband signals. Many studies have recently been published devoted to this technology. However, the practical implementations of chaos-based communications are rare due to multiple shortcomings: high hardware requirements, complex signal processing algorithms, and a lack of efficient modulation techniques for chaotic signals. In this study, we consider a simple hardware prototype of a coherent chaos-based communication system based on a novel type of modulation: adaptive symmetry of the finite-difference scheme used in a chaos generator. We explicitly demonstrate the possibility of covertly transmitting data using a chaotic transmitter and receiver implemented in a general-purpose microcontroller unit. A comparison between traditional parameter and symmetry modulation is given through a return map analysis and bit error rate estimation. The communication secrecy is analyzed using quantified return map analysis. The obtained results confirm the possibility of creating chaos-based communication systems based on symmetry modulation.
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Mahdi Katsumata Shah, Bruno Jactat, Toshiyuki Yasui, and Murod Ismailov
- Education Sciences, Vol 13, Iss 53, p 53 (2023)
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prototyping, design thinking, higher education institution, HEI management, cognitive biases, and Education
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A project using design thinking (DT) was conducted among internal stakeholders of a large state Japanese university to design a user-centric brochure promoting study abroad programs at francophone partner universities. The low-fidelity prototype and the final product created with DT were tested by asking potential student-users to compare it with a standard brochure through two sets of surveys. Analysis of the quantitative and qualitative data revealed that low-fidelity prototyping was effective to enhance both the utility and usability of the final product. We also show how DT helped expose cognitive biases among designers.
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Michał Szelka, Andrzej Drwięga, Jarosław Tokarczyk, Marek Szyguła, Kamil Szewerda, Marian Banaś, Krzysztof Kołodziejczyk, and Krzysztof Kędzia
- Energies, Vol 16, Iss 542, p 542 (2023)
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axial fan, ventilation, efficiency, rapid prototyping, CFD, FEM, and Technology
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The article discusses the process of designing and testing as well as their results, carried out in order to increase the efficiency of axial fans, implemented as part of the European project INESI. Modifications of existing solutions based on rapid prototyping methods were presented. Scanning, FEM and CFD numerical calculations and 3D printing were used for that purpose. Rapid prototyping involved the use of a steel blade base and 3D-printed complex aerodynamic shapes that were bonded to create completely new blades. After their installation on the new rotor, enabling the angle of attack adjusting, a number of verifying tests of the fan were carried out. The solution was successfully tested and the results are discussed in the article.
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Loris Ventura, Roberto Finesso, and Stefano A. Malan
- Energies, Vol 16, Iss 907, p 907 (2023)
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diesel engine, machine learning engine management, neural network models, control system coordination, and Technology
- Abstract
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The tightening of diesel pollutant emission regulations has made Internal Combustion Engine (ICE) management through steady-state maps obsolete. To overcome the map’s scarce performance and efficiently manage the engine, control systems must cope with ICE transient operations, the coupling between its subsystem dynamics, and the tradeoff between different requirements. The work demonstrates the effectiveness of a reference generator that coordinates the air path and combustion control systems of a turbocharged heavy-duty diesel engine. The control system coordinator is based on neural networks and allows for following different engine-out Nitrogen Oxide (NOx) targets while satisfying the load request. The air path control system provides the global conditions for the correct functioning of the engine, targeting O2 concentration and pressure in the intake manifold. Through cooperation, the combustion control targets Brake Mean Effective Pressure (BMEP) and NOx to react to rapid changes in the engine operating state and compensates for the remaining deviations with respect to load and NOx targets. The reference generator and the two controller algorithms are suitable for real-time implementation on rapid-prototyping hardware. The performance overall was good, allowing the engine to follow different NOx targets with 150 ppm of deviation and to achieve an average BMEP error of 0.3 bar.
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Cahyo Hasanudin, Subyantoro, Ida Zulaeha, and Rahayu Pristiwati
- European Journal of Educational Research, Vol 12, Iss 1, Pp 435-453 (2023)
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Education
- Abstract
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This study aims to investigate lecturers' needs for academic writing learning materials and determine their prototypes. This study is qualitative research in the form of an exploratory case study. The research instruments were semi-open-ended questionnaires and unstructured and open-ended interview guides. The data were analyzed using content analysis. The results show that the developed learning material for academic writing skills contains seven needs for lecturers in the Department of Indonesian Language and Literature. Four of them have not been found by previous researchers. The results from this study provide new knowledge and contribution to the literature about the need to prototype the learning materials. The lecturers or other researchers can use these seven needs in prototyping learning materials for academic writing skills, such as the needs of learning materials, their forms, presentation system, language use, evaluation form, main menu design, and the way of creating learning materials.
- Full text View record in DOAJ
48. Customizable 3D printed perfusion bioreactor for the engineering of stem cell microenvironments [2023]
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Steven J. Dupard, Alejandro Garcia Garcia, and Paul E. Bourgine
- Frontiers in Bioengineering and Biotechnology, Vol 10 (2023)
- Subjects
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3D printing, polylactic acid, bioreactor, mesenchymal niche, hematopoiesis, collagen scaffold, Biotechnology, and TP248.13-248.65
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Faithful modeling of tissues and organs requires the development of systems reflecting their dynamic 3D cellular architecture and organization. Current technologies suffer from a lack of design flexibility and complex prototyping, preventing their broad adoption by the scientific community. To make 3D cell culture more available and adaptable we here describe the use of the fused deposition modeling (FDM) technology to rapid-prototype 3D printed perfusion bioreactors. Our 3D printed bioreactors are made of polylactic acid resulting in reusable systems customizable in size and shape. Following design confirmation, our bioreactors were biologically validated for the culture of human mesenchymal stromal cells under perfusion for up to 2 weeks on collagen scaffolds. Microenvironments of various size/volume (6–12 mm in diameter) could be engineered, by modulating the 3D printed bioreactor design. Metabolic assay and confocal microscopy confirmed the homogenous mesenchymal cell distribution throughout the material pores. The resulting human microenvironments were further exploited for the maintenance of human hematopoietic stem cells. Following 1 week of stromal coculture, we report the recapitulation of 3D interactions between the mesenchymal and hematopoietic fractions, associated with a phenotypic expansion of the blood stem cell populations.Our data confirm that perfusion bioreactors fit for cell culture can be generated using a 3D printing technology and exploited for the 3D modeling of complex stem cell systems. Our approach opens the gates for a more faithful investigation of cellular processes in relation to a dynamic 3D microenvironment.
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Lamees M. Al Qassem, Thanos Stouraitis, Ernesto Damiani, and Ibrahim Abe M. Elfadel
- IEEE Access, Vol 11, Pp 2570-2585 (2023)
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Microservices, autoscalers, resource allocation, resource utilization, machine learning, random forest, Electrical engineering. Electronics. Nuclear engineering, and TK1-9971
- Abstract
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Cloud service providers have been shifting their workloads to microservices to take advantage of their modularity, flexibility, agility, and scalability. However, numerous obstacles remain to achieving the most out of microservice deployments, especially in terms of a Quality of Service (QoS). One possible approach to overcoming these obstacles is to perform autoscaling, which is the ability of cloud infrastructure and services to scale themselves up or down by changing their resource pool. There are two major categories of autoscaling: reactive and proactive. In reactive autoscaling, a feedback loop based on current workload resource usage is implemented to guide resource scaling. One disadvantage of reactive autoscaling is that it may result in inconsistencies between workload demand and resource allocation. In proactive autoscaling, a prediction model is used to guide the future allocation of resources according to current workload metrics. In this paper, a novel proactive autoscaling method is introduced where a two-state, machine-learning Random Forest (RF) model is designed to forecast the future CPU and memory utilization values required by the microservice workload. These predicted values are then used to adjust the resource pool both vertically (hardware resources) and horizontally (microservice replicas). The RF proactive autoscaler has been implemented on a home-grown, open-source microservice prototyping platform and verified using real-world workloads. The experiments show that the RF proactive autoscaler outperforms state-of-the-art ones in terms of allocated resources and latency. The increase in the utilization of allocated resources can reach 90% and the improvement in end-to-end latency, measured by the $95^{th}$ percentile, can reach 95%.
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Carolina Blanco-Angulo, Andrea Martinez-Lozano, Julia Arias-Rodriguez, Alberto Rodriguez-Martinez, Jose Maria Vicente-Samper, Jose Maria Sabater-Navarro, and Ernesto Avila-Navarro
- IEEE Access, Vol 11, Pp 4010-4022 (2023)
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Direct-ink-writing, silver-conductive ink, additive manufacturing, printed electronics, ultra-wideband antennas, electrical conductivity, Electrical engineering. Electronics. Nuclear engineering, and TK1-9971
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Direct ink writing (DIW) of conductive ink is a printed electronics technology that allows a variety of electronic circuits to be produced in a simple way and with minimal waste of materials. In recent years it has been used for rapid prototyping of RF circuits typically working at S-band frequencies (2–4 GHz). In an attempt to extend this frequency range while maintaining cost-effective prototyping, this work has focused on proving the feasibility of DIW of silver-conductive (SC) ink for the fabrication of planar microwave circuits beyond 10 GHz, more specifically, ultra-wideband (UWB) antennas for medical applications. For this purpose, the DC and RF performance of the SC ink, as well as the FR4 substrate used, were first evaluated. Based on the comparison between experimental and simulated results, we have found that the effective RF conductivity of the SC ink is approximately 27.6% of its DC value and 3.4% of the copper conductivity. A few test microstrip circuits were fabricated by DIW, namely two S-band filters and one UWB antenna. The overall measured performance of all of them agreed well with simulations. In particular, the DIW antenna exhibited a bandwidth of 8.2 GHz (between 2.4 and 10.6 GHz), and was compared with an identical copper antenna showing that both have very similar characteristics. It was also found that the lower conductivity of SC ink as compared to copper led to a gain reduction of only 0.3 dB.
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Levi Bieber, Liwei Wang, Juri Jatskevich, and Wei Li
- IEEE Access, Vol 11, Pp 4228-4241 (2023)
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FPGA, hybrid multilevel converter, modular multilevel converter (MMC), rapid control prototyping (RCP), real-time simulation, voltage-source converter high voltage direct current (VSC-HVDC), Electrical engineering. Electronics. Nuclear engineering, and TK1-9971
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Real-time simulation is important for ensuring the reliable operation of VSC-HVDC converters in power grids, particularly through the use of rapid control prototyping (RCP) and hardware-in-the-loop (HIL) based converter controllers. While real-time simulation is a common practice for modular multilevel converters (MMCs), it has been less frequently applied to the new class of hybrid cascaded multilevel converters (HCMCs). In this study, a universal equivalent model (UEM) is proposed for a range of HCMC topologies that combines accuracy and computational efficiency through the use of both CPUs and field-programmable gate arrays (FPGAs). The proposed UEM is derived using the hybrid five-level converter (H5LC), a compact, efficient, and fault-tolerant VSC within the HCMC family. The UEM relies on CPUs to simulate the main circuits and controls of the main converter, and utilizes FPGAs to calculate the instantaneous voltages of a large number of full-bridge submodules (FBSMs), flying capacitors, and DC-side pole capacitors. In addition, the FBSMs’ voltage-balancing and switching algorithms are implemented on the FPGAs. The proposed real-time CPU/FPGA-based H5LC-UEM is compared to an offline CPU-based detailed equivalent model to verify its accuracy.
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52. Development of the Hands-free AI Speaker System Supporting Hands-on Science Laboratory Class [2023]
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Gyeong-Geon Lee, Minji Choi, Taesoo An, Seonyeong Mun, and Hun-Gi Hong
- International Journal of Emerging Technologies in Learning (iJET), Vol 18, Iss 01 (2023)
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AI in education (AIEd), hands-free AI speaker, hands-on science laboratory class, rapid prototyping, natural language processing (NLP), Education, Information technology, and T58.5-58.64
- Abstract
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The recent progress of natural language processing (NLP), speech recognition, and speech generation envisions using hands-free artificial intelligence (AI) speakers in classrooms to support student learning. In science education, the conventional hands-on laboratory education has been considered crucial in fostering students’ manipulative experimentation skills. However, touching things with gloved hands other than experimental equipment and apparatuses is strictly restricted because of the safety issue, which calls for another channel to get timely support. Therefore, we ideated that adopting hands-free AI speakers in the hands-on science laboratory classroom would support student learning. Using the rapid prototyping method, we designed and developed an AI speaker-based system that answers student queries concerning solution-making, experimental process, and waste liquid disposal, which corresponds to the initial, middle, and final phases of a laboratory class. The system was internally validated by usability tests of 9 expert panels and 18 university students, and then revised. The revised system was externally validated in an analytical chemistry experiment class for 3 sessions with 13 university students. We present the result of the prototype development, internal and external validations with quantitative and qualitative data. The AI speaker system enabled students to use the auditory learning mode in the laboratory while concentrating on the experimentation with their hands in the external validation.
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53. Computer-Aided Greenery Design—Prototype Green Structure Improving Human Health in Urban Ecosystem [2023]
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Dominik Sędzicki, Jan Cudzik, and Lucyna Nyka
- International Journal of Environmental Research and Public Health, Vol 20, Iss 1198, p 1198 (2023)
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greenery, automated design, sustainability, public health, landscape design, architecture, and Medicine
- Abstract
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Increasing population and urbanization, with climate change consequences, such as rising temperatures, influence public health and well-being. The search to improve the quality of life in cities becomes one of the priority objectives. A solution can be found in the role of greenery in an urban environment and its impact on human health. This opens a path toward experimentation on microclimate green structures that can be inserted into dense urban spaces providing human and environmental benefits. The article proposes an automated greenery design method combined with rapid prototyping for such interventions. A theoretical analysis of the problem preceded the introduction of the method. The research process was developed in accordance with the main objectives of the CDIO framework (Conceive, Design, Implement, and Operate) with the SiL (Software in the Loop) and HiL (Hardware in the Loop) methods. Moreover, the applied test model allows for complex evaluation in order to ensure quality and directions for further development.
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Belinda Li, Tammara Soma, Nadia Springle, and Tamara Shulman
- International Journal of Qualitative Methods, Vol 22 (2023)
- Subjects
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Social sciences (General) and H1-99
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Qualitative research methods had to quickly adapt to using online platforms due to the COVID-19 pandemic to limit in-person interactions. Online platforms have been used extensively for interviews and focus groups, but workshops with larger groups requiring more complex interactions have not been widely implemented. This paper presents a case study of a fully virtual social innovation lab on bioplastics packaging, which was adapted from a series of in-person workshops. A positive outcome of the online setting was diversifying the types of participants who could participate. Highly interactive activities such as icebreakers, networking, bricolage, and prototyping were particularly challenging to shift from in-person to online using traditional web conferencing platforms like Zoom. Creative use of online tools, such as Gather.Town and Kahoot!, helped unlock more innovative thinking by employing novel techniques such as gamification. However, challenges such as adapting facilitation for an online environment and exclusion of groups that do not have consistent access to internet and/or computers still need to be addressed. The reflections and lessons learned from this paper can help researchers adapt qualitative methods to virtual environments.
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Ahmed ELbarbary and Noha Magdy
- Journal of Architecture, Art & Humanistic Science, Vol 8, Iss 37, Pp 121-143 (2023)
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3dtechnology, pattern, prototyping, garment factories, virtual simulation), Fine Arts, Architecture, and NA1-9428
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3D technology is considered one of the Pattern digital technologies that help this technology to increase, ease and speed of completion of industrial processes. This study deals with how to take advantage of 3D technology in developing the performance of the samples department in the technical department of ready-to-wear factories, in order to solve the problems of the samples section associated with the implementation of the 2D Pattern, as this problem was concluded through field study and practical experiences in ready-to-wear factories in Egypt.Controlling the fitting Pattern of clothes in the samples section faces many difficulties, the most important of which is the incompatibility of the industrial Pattern drawn with the human body “Pattern ". Where defects appeared in the product after conducting and implementing the first sample, which required making adjustments to the industrial Pattern and re-executing the sample a second time until it became free from defects and ready to perform the grading according to the measurements and the "order" of the operation order required to be executed to start production processes, which results in it. In the presence of lost time to implement the sample, as well as wasted effort, and wastes in the raw materials used in the implementation of the sample (fabric/ accessories / threads / and direct and indirect costs) that will be quantified after that.In order to find a solution to this problem, this research presents a case study using the "CLO5.1" program to improve the industrial Pattern in order to improve the quality of the male industrial Pattern drawing using 3D technology by making adjustments to some areas where the stress and stress ratios are high due to the lack of nan fitting of the Pattern. Industrial, which does not appear clearly even during implementation. The study concluded that the implementation of the CLO5.1 program in the sample section has succeeded in reducing the time wastage for sample production and the wastage of raw materials, thus reducing the cost of sample productionKey words :( 3Dtechnology ، pattern، Prototyping ، Garment Factories ،virtual simulation)
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Caterina Credi, Roberto Bernasconi, Marinella Levi, and Luca Magagnin
- Journal of Materials Research and Technology, Vol 22, Iss , Pp 1855-1867 (2023)
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Stereolithography, Composite, Nickel, Electroless plating, Selective metallization, Mining engineering. Metallurgy, and TN1-997
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The integration of multifunctional elements directly embedded in three-dimensional (3D) printed parts is the cutting-edge of additive manufacturing (AM) and it is crucial for enlarging as well as for strengthening AM role in industrial applications. Here, a straightforward and low-cost method that synergically combines stereolithography (SLA) and selective electroless metallization (EM) is presented for the fabrication of 3D parts characterized by complex shapes and end-use multifunctionalities (conductive, magnetic, mechanical properties). To this end, a novel photocurable composite based on acrylate resin loaded with nickel (Ni) particles is developed for high-resolution SLA-printing of features with self-catalytic properties for EM. Ni particles are loaded in the resin to trigger metal deposition avoiding time consuming and expensive laser-based surface activation. The effect of Ni content on SLA behavior as well as on the efficiency of EM process is studied. Metallized SLA cured samples show good electrical and magnetic properties as well as improved robustness with respect to their non-loaded counterparts. Then, selective metallization of 3D printed parts is successfully achieved by implementing a multi-material SLA-printing where loaded and non-loaded resins are properly interchanged with strong adhesion at the interface, thus offering a cost-effective approach for rapid prototyping of functional free-form features on 3D structures.
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Indrie Noor Aini, Zulkardi, Ratu Ilma Indra Putri, and Poppy Yaniawati
- Journal on Mathematics Education, Vol 13, Iss 4, Pp 723-738 (2023)
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design research, historical buildings’ context, pisa-like math problems, space and shape, Mathematics, and QA1-939
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The essential purpose of developing PISA-like questions is to train students' reasoning abilities so that students' ability to solve PISA-like questions increases. Therefore, this research aims to produce PISA-like math problems in the context of historical buildings in the Karawang Regency that are valid, practical, and potentially affect mathematics learning. The subjects of this study were junior high school students at SMPN 2 Karawang Barat. This research uses design research with development studies, consisting of preliminary and prototyping phases. The preliminary stage consists of two stages: needs analysis and design, while the prototyping stage consists of 5 phases: self-evaluation, expert review, one-to-one, small group, and field tests. The data collection techniques in this study were in the form of PISA-like math problems in the context of shape and space with the context of Historic Buildings in Karawang, observations, questionnaires, and interviews. All data obtained were analyzed descriptively. The results show that this study resulted in nine PISA-like math problems in the context of shape and space with the context of Historic Buildings in Karawang that are valid, practical, and potentially affect learning mathematics. The potential effect is related to students' interest in PISA-like questions and students' ability to understand and answer PISA-like questions. Finally, the results of this study have an impact on students who are getting trained in solving PISA-like math problems.
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Nourma Pramestie Wulandari, Nani Kurniati, Nurul Hikmah, and Wahidaturrahmi Wahidaturrahmi
- Jurnal Elemen, Vol 9, Iss 1, Pp 98-108 (2023)
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mathematical literacy, minimum competency assessment, numeracy problems, numeration, question exercise book, Mathematics, and QA1-939
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Numeracy has become part of the Minimum Competency Assessment (MCA) used in the National Assessment (NA) since it was established in 2021. However, previous research shows that the numeracy skills of junior high school students are still in the low category. The purpose of this study was to obtain a prototype of a practice book about preparation for dealing with numeracy MCA for junior high school students that were valid, according to experts. This research was development research (RD) using the Plomp development model, which consists of preliminary research, a prototyping phase, and an assessment phase. At the end of the development stage, there was a formative evaluation to assess the product development's validity by two experts. The instrument used was the validation sheet for the numerical problems book. The results of this study obtained a prototype of the book that contains at least 90 numeracy problems for Junior High School students, which was categorized as valid with an average score of 89 and an excellent classification. The questions used include multiple choice, multiple complex choice, matchmaking, short essay questions, and essay. The dominant portion is in the form of complex multiple-choice questions. This book is suitable for students' preparation for the numeracy MCA.
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59. Rancang Bangun Aplikasi Computer-based Test (CBT) serta Optimasinya Menggunakan Cache dan Queue Job [2023]
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Rahmat Siswanto and Dwi Senjaya A. Morang
- Jurnal Komputer Terapan, Vol 8, Iss 2, Pp 391-407 (2023)
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cbt, queue job, prototyping, cache, Science, Electronic computers. Computer science, and QA75.5-76.95
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Examinations in schools that still use paper require a great deal of time, effort and money to implement, especially in the activities of printing, duplicating and distributing exam questions to students who will take the exam. Therefore, we need a system that can facilitate the filling, duplication and distribution of questions at a small cost. Based on these problems, a web-based CBT application was built that can be accessed anywhere and anytime and can work on multiple platforms (multi-platform). This system was built using the prototyping method to make it easier for developers and users to develop applications from the initial prototype to the production stage. In practice, this application is expected to be able to accommodate exam activities for all students in the school at the same time. Based on this, the application that is made must have reliability and accuracy starting from the process of carrying out the exam to displaying the results. Researchers apply a cache and queue job system to the application to get maximum results. From the results of tests that have been carried out in three stages, the results show that this web-based CBT application is able to accommodate exam activities in schools with a total of 250 students in one exam session and can display a recap of exam results from all participants.
- Full text View record in DOAJ
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Andrzej Malewski, Marcin Kozłowski, Jacek Podwórny, Marcin Środa, and Wojciech Sumelka
- Materials, Vol 16, Iss 397, p 397 (2023)
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glass formation, soda-lime silicate glass, numerical modeling, modern architecture, literature review, glass production, 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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Architectural soda-lime silicate glass (SLS) is increasingly taking on complex shapes that require more detailed numerical analysis. Glass modeling is a thoroughly described topic with validated constitutive models. However, these models require a number of precise material parameters for SLS glass, and these are very sensitive to changes in glass composition. The currently available information is based on SLS glass tested in the late 1990s. As a result, most current publications are based on the above data. The object of this work was to analyze the available sources and update the information on selected key parameters for modeling. Using the currently utilized SLS glass in construction, the coefficient of thermal expansion (CTE), glass transition temperature, and the Young’s modulus have been experimentally investigated. The updated material parameters will allow for more accurate modeling of the SLS glass currently used in construction, and in consequence will make the prototyping process for glass with complex geometries possible to be transferred from the production stage to the design stage, resulting in shorter production times.
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Jerzy Bochnia
- Materials, Vol 16, Iss 400, p 400 (2023)
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3D printing, PJM, photocurable resins, polymers, polymer aging, 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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Additive manufacturing is being increasingly used both for rapid prototyping as well as the fabrication of finished components. It is important to determine how the properties of 3D printed materials change over time and how they affect the durability and usability of products. The aim of the research presented in this article was to find out what influence the natural aging period had on the mechanical properties, especially the tensile strength and modulus of elasticity, of specimens made from the selected photocurable resins using the PolyJet Matrix (PJM) technology. The tests involved determining the tensile strength and modulus of elasticity of specimens fabricated in 2013 and 2014 using two types of photosensitive resins, i.e., FullCure 720 and VeroWhite, respectively. Some of the specimens were stored under laboratory conditions until July 2022 and then tested using a universal testing machine. The experimental data obtained in 2022 for the naturally aged models were compared with those reported for the as-printed specimens. One of the main findings of this study was that the tensile strength and modulus of elasticity of the naturally aged specimens were largely dependent on the printing direction (model orientation on the build tray). The test results show that aging generally decreased the tensile strength of the specimens. In one case, however, an increase in this property was observed. For the X and Y printing directions, Rm declined by 27.1% and 30.7%, respectively. For the Z direction, a decrease of only 5.5% was reported, for Full Cure 720. The modulus of elasticity of the models tested in 2022 differed considerably from that reported for the as-printed objects. Higher values of the modulus of elasticity implied that the material stiffness increased over time, and this is a common phenomenon in polymers. Interesting results were obtained for VeroWhite specimens. The modulus of elasticity decreased significantly by 25.1% and 42.4% for the specimens printed in the X and Z directions, respectively. However, for the models built in the Y direction, it increased by 27.4%. The experimental data may be of significance to users of products manufactured using the PJM method as well as to researchers dealing with the durability and reliability of such materials.
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Muhammad Umer Shan and Salman Hussain
- Mehran University Research Journal of Engineering and Technology, Vol 42, Iss 1, Pp 42-55 (2023)
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Technology, Engineering (General). Civil engineering (General), TA1-2040, and Science
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In a contemporary era, Additive Manufacturing (AM), 3D printing or rapid prototyping has evolved as a distinctive method when compared with the traditional manufacturing. By addressing the topic of Design for Additive Manufacturing (DFAM), it is observed that the basic principles of DFAM and Design for Assembly (DFA) are well established and usually applicable on small-size AM parts. To address this critical manufacturing decision, our research work presents a new decision support system (DSS) for a large-size AM part which is based on compiling the existing DFAM methodologies. Before presenting the new DSS, the previous DFAM approaches are reviewed and investigated the research trends in part decomposition (PD), part consolidation (PC), and topology optimization (TO). The literature is categorized into six distinctive categories and among them the first phase is the information phase. Following this information requisite step, the next phase is parameter assessment phase and so on. The new DSS starts with the clarification of the design goal while in previous approaches this step was usually done at the later stages. Similarly, the remaining steps are efficiently integrated into the framework structure. The developed system is also guiding the post-decomposition assembly process. The developed DSS is validated using the case study of a 6-axis robotic arm. Moreover, a comprehensive concept for using the developed DSS framework is also presented in the research work.
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Margherita Pizzi, Francesco De Gaetano, Marco Ferroni, Federica Boschetti, and Massimiliano Annoni
- Micromachines, Vol 14, Iss 132, p 132 (2023)
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microdrilling, magnesium, microholes, micromachinability, holes quality, chip formation, Mechanical engineering and machinery, and TJ1-1570
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The mechanisms of deep-hole microdrilling of pure Mg material were experimentally studied in order to find a suitable setup for a novel intraocular drug delivery device prototyping. Microdrilling tests were performed with 0.20 mm and 0.35 mm microdrills, using a full factorial design in which cutting speed vc and feed fz were varied over two levels. In a preliminary phase, the chip shape was evaluated for low feeds per tooth down to 1 μm, to verify that the chosen parameters were appropriate for machining. Subsequently, microdrilling experiments were carried out, in which diameter, burr height and surface roughness of the drilled holes were examined. The results showed that the burr height is not uniform along the circumference of the holes. In particular, the maximum burr height increases with higher cutting speed, due to the thermal effect that plasticizes Mg. Hole entrance diameters are larger than the nominal tool diameters due to tool runout, and their values are higher for high vc and fz. In addition, the roughness of the inner surface of the holes increases as fz increases.
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Kwan YH, Ong ZQ, Choo DYX, Phang JK, Yoon S, and Low LL
- Patient Preference and Adherence, Vol Volume 17, Pp 1-11 (2023)
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type 2 diabetes mellitus, mhealth, mobile app, Medicine (General), and R5-920
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Yu Heng Kwan,1– 4 Zhi Quan Ong,5 Dawn Yee Xi Choo,1 Jie Kie Phang,2,4 Sungwon Yoon,2,4 Lian Leng Low2,4,6– 9 1Department of Pharmacy, National University of Singapore, Singapore, Singapore; 2Health Services and Systems Research, Duke-NUS Medical School, Singapore, Singapore; 3Internal Medicine Residency, SingHealth, Singapore, Singapore; 4Centre for Population Health Research and Implementation, SingHealth Regional Health System, Singapore, Singapore; 5School of Computing, National University of Singapore, Singapore, Singapore; 6Population Health & Integrated Care Office (PHICO), Singapore General Hospital, Singapore, Singapore; 7Department of Family Medicine and Continuing Care, Singapore General Hospital, Singapore, Singapore; 8Post-Acute and Continuing Care, Outram Community Hospital, Singapore, Singapore; 9SingHealth Duke-NUS Family Medicine Academic Clinical Program, Singapore, SingaporeCorrespondence: Lian Leng Low, Department of Family Medicine & Continuing Care, Singapore General Hospital, 20 College Road, Singapore, 169856, Singapore, Tel +65 63265872, Email low.lian.leng@singhealth.com.sgBackground: Diabetes is a global public health issue, causing burden on healthcare system and increasing risk of mortality. Mobile applications (apps) can be a promising approach to facilitate diabetes self-management. An increasingly utilized approach to facilitate engagement with mobile health (mHealth) technology is to involve potential users in the creation of the technology.Objective: The aim of this study was to use co-design for type 2 diabetes mellitus (T2DM) self-management mHealth development.Methods: Three rounds of iterative rapid prototyping panel sessions were conducted with a total of 9 T2DM participants in an Asian setting between Oct 2020 and April 2021. The participants were recruited through convenience sampling. For each round, feedback was gathered through qualitative interviews, and the feedback was used as a reference by the development team to develop and test a more refined version of the app in the next round. Transcribed semi-structured interview data was analyzed thematically using an inductive approach.Results: Participants’ ages ranged from 40 to 69 years. Data saturation was reached, with no new themes emerging from the data. During the sessions, the participants expressed a variety of concerns and feedback on T2DM self-management using EMPOWER app and raised suggestions on the features of ideal T2DM self-management app. Important features include 1) reminders and notifications for medications, 2) Bluetooth integration with glucometers and blood pressure machines to minimize manual entry, 3) enlarged local food database including information on sugar content and recommendations for healthier options, 4) one touch for logging of routine medications and favorite foods, 5) export function for data sharing with physicians. Overall inputs concerned aspects such as user-friendliness of the app, customization possibilities, and educational content for the features in the mobile app.Conclusion: In this study, we explored users’ opinions on a T2DM self-management mobile app using co-design approach. This study adds to the growing body of literature on co-designing behavioral mHealth interventions and can potentially guide researchers in mobile app design for other chronic conditions.Keywords: type 2 diabetes mellitus, mHealth, mobile app
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Antonella Sola, Wei Juene Chong, Dejana Pejak Simunec, Yuncang Li, Adrian Trinchi, Ilias (Louis) Kyratzis, and Cuie Wen
- Polymer Testing, Vol 117, Iss , Pp 107859- (2023)
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Tensile properties, International standard, Size effect, Additive manufacturing, Fused filament fabrication, Fused deposition modeling, Polymers and polymer manufacture, and TP1080-1185
- Abstract
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Additive manufacturing (AM, also commonly termed 3D printing) is progressing from being a rapid prototyping tool to serving as pillar of the Industry 4.0 revolution. Thanks to their low density and ease of printing, polymers are receiving increasing interest for the fabrication of structural and lightweight parts. Nonetheless, the lack of appropriate standards, specifically conceived to consistently verify the tensile properties of polymer parts and benchmark them against conventional products, is a major obstacle to the wider uptake of polymer AM in industry. After reviewing the standardisation needs in AM with a focus on mechanical testing, the paper closely examines the hurdles that are encountered when existing standards are applied to measure the tensile properties of polymer parts fabricated by fused filament fabrication (FFF, aka fused deposition modeling, FDM), which is presently the most popular material extrusion AM technique. Existing standards are unable to account for the numerous printing parameters that govern the mechanical response of FFF parts. Moreover, the literature suggests that the raster- and layer-induced anisotropic behaviour and the complicated interplay between structural features at different length scales (micro/meso/macro-structure) undermine pre-existing concepts regarding the specimen geometry and classical theories regarding the size effect, and ultimately jeopardise the transferability of conventional tensile test standards to FFF parts. Finally, the statistical analysis of the tensile properties of poly(lactic acid) (PLA) FFF specimens printed according to different standards (ASTM D638 type I and ASTM D3039) and in different sizes provides experimental evidence to confirm the literature-based argumentation. Ultimately, the literature survey, supported by the experimental results, demonstrates that, until dedicated standards become available, existing standards for tensile testing should be applied to FFF with prudence. Whilst not specified in conventional standards, set-up and printing parameters should be fully reported to ensure the repeatability of the results, rectangular geometries should be preferred to dumbbell-like ones in order to avoid premature failure at the fillets, and the size of the specimens should not be changed arbitrarily.
- Full text View record in DOAJ
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Carlie Rein, Mehmet Toner, and Derin Sevenler
- Scientific Reports, Vol 13, Iss 1, Pp 1-9 (2023)
- Subjects
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Medicine and Science
- Abstract
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Abstract Soft lithography has permitted rapid prototyping of precise microfluidic features by patterning a deformable elastomer such as polydimethylsiloxane (PDMS) with a photolithographically patterned mold. In microfluidics applications where the flexibility of PDMS is a drawback, a variety of more rigid materials have been proposed. Compared to alternatives, devices fabricated from epoxy and glass have superior mechanical performance, feature resolution, and solvent compatibility. Here we provide a detailed step-by-step method for fabricating rigid microfluidic devices from soft lithography patterned epoxy and glass. The bonding protocol was optimized yielding devices that withstand pressures exceeding 500 psi. Using this method, we demonstrate the use of rigid high aspect ratio spiral microchannels for high throughput cell focusing.
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Liao Chen, Chenguang Zhang, Vivek Yadav, Angela Wong, Satyajyoti Senapati, and Hsueh-Chia Chang
- Scientific Reports, Vol 13, Iss 1, Pp 1-13 (2023)
- Subjects
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Medicine and Science
- Abstract
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Abstract Droplet microfluidics offers a platform from which new digital molecular assay, disease screening, wound healing and material synthesis technologies have been proposed. However, the current commercial droplet generation, assembly and imaging technologies are too expensive and rigid to permit rapid and broad-range tuning of droplet features/cargoes. This rapid prototyping bottleneck has limited further expansion of its application. Herein, an inexpensive home-made pipette droplet microfluidics kit is introduced. This kit includes elliptical pipette tips that can be fabricated with a simple DIY (Do-It-Yourself) tool, a unique tape-based or 3D printed shallow-center imaging chip that allows rapid monolayer droplet assembly/immobilization and imaging with a smart-phone camera or miniature microscope. The droplets are generated by manual or automatic pipetting without expensive and lab-bound microfluidic pumps. The droplet size and fluid viscosity/surface tension can be varied significantly because of our particular droplet generation, assembly and imaging designs. The versatility of this rapid prototyping kit is demonstrated with three representative applications that can benefit from a droplet microfluidic platform: (1) Droplets as microreactors for PCR reaction with reverse transcription to detect and quantify target RNAs. (2) Droplets as microcompartments for spirulina culturing and the optical color/turbidity changes in droplets with spirulina confirm successful photosynthetic culturing. (3) Droplets as templates/molds for controlled synthesis of gold-capped polyacrylamide/gold composite Janus microgels. The easily fabricated and user-friendly portable kit is hence ideally suited for design, training and educational labs.
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Andrea Alimenti, Kostiantyn Torokhtii, Pablo Vidal García, Nicola Pompeo, and Enrico Silva
- Sensors, Vol 23, Iss 518, p 518 (2023)
- Subjects
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dielectric-loaded resonator, surface resistance measurement, complex permittivity measurement, microwave material characterization, 3D printing materials, Chemical technology, and TP1-1185
- Abstract
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The spread of additive manufacturing techniques in the prototyping and realization of high-frequency applications renewed the interest in the characterization of the electromagnetic properties of both dielectric and conductive materials, as well as the design of new versatile measurement techniques. In this framework, a new configuration of a dielectric-loaded resonator is presented. Its optimization, realization, and use are presented. A measurement repeatability of about one order of magnitude lower than the commonly found values (10−3 on the Q-factor and 15×10−6 on the resonance frequency, given in terms of the relative standard deviations of repeated measurements) was reached thanks to the design of a closed resonator in which the samples can be loaded without disassembling the whole measurement fixture. The uncertainty levels, the ease of use, and the versatility of the realized system make its use of potential interest in numerous scenarios.
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69. Agile Methodologies Applied to the Development of Internet of Things (IoT)-Based Systems: A Review [2023]
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Gleiston Guerrero-Ulloa, Carlos Rodríguez-Domínguez, and Miguel J. Hornos
- Sensors, Vol 23, Iss 790, p 790 (2023)
- Subjects
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Internet of Things (IoT), development methodologies, agile methodologies, software engineering, Model-Based Engineering, Model-Driven Engineering, Chemical technology, and TP1-1185
- Abstract
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Throughout the evolution of software systems, empirical methodologies have been used in their development process, even in the Internet of Things (IoT) paradigm, to develop IoT-based systems (IoTS). In this paper, we review the fundamentals included in the manifesto for agile software development, especially in the Scrum methodology, to determine its use and role in IoTS development. Initially, 4303 documents were retrieved, a number that was reduced to 186 after applying automatic filters and by the relevance of their titles. After analysing their contents, only 60 documents were considered. Of these, 38 documents present the development of an IoTS using some methodology, 8 present methodologies focused on the construction of IoTS software, and 14 present methodologies close to the systems life cycle (SLC). Finally, only one methodology can be considered SLC-compliant. Out of 38 papers presenting the development of some IoTS following a methodology for traditional information systems (ISs), 42.1% have used Scrum as the only methodology, while 10.5% have used Scrum combined with other methodologies, such as eXtreme Programming (XP), Kanban and Rapid Prototyping. In the analysis presented herein, the existing methodologies for developing IoTSs have been grouped according to the different approaches on which they are based, such as agile, modelling, and service oriented. This study also analyses whether the different proposals consider the standard stages of the development process or not: planning and requirements gathering, solution analysis, solution design, solution coding and unit testing (construction), integration and testing (implementation), and operation and maintenance. In addition, we include a review of the automated frameworks, platforms, and tools used in the methodologies analysed to improve the development of IoTSs and the design of their underlying architectures. To conclude, the main contribution of this work is a review for IoTS researchers and developers regarding existing methodologies, frameworks, platforms, tools, and guidelines for the development of IoTSs, with a deep analysis framed within international standards dictated for this purpose.
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Nicola Kristanto
- Sibatik Journal, Vol 2, Iss 2, Pp 609-622 (2023)
- Subjects
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arduino, accelerometer, firebase, mysql, Social Sciences, and Technology
- Abstract
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Indonesia berada dalam cincin api atau biasa disebut ring of fire karena dikelilingi oleh banyak gunung berapi sehingga kemungkinan untuk terjadinya bencana alam gempa cukup besar potensi nya. Ketika bencana alam gempa terjadi, masih banyak masyarakat kurang tanggap dalam menyadarinya, Banyak juga korban jiwa yang pada akhirnya tidak dapat menyelamatkan diri karena minimnya informasi gempa terjadi dan terlambat dalam melakukan evakuasi diri. Tujuan penelitian ini adalah untuk membuat inovasi untuk memberi solusi kepada masyarakat dengan membuat alat pendeteksi gempa yang dilengkapi oleh sensor Accelerometer adxl335 dan sensor getar SW-420 berbasis Arduino dengan sistem informasinya. Metode penelitian menggunakan metode pembuatan IoT pendeteksi gempa. Metode untuk perancangan dashboard akan menggunakan metode prototyping. Hasil penelitian antara lain adalah alat ini terdiri dari mikrokontroler Arduino Uno R3 untuk mengolah data output dari sensor, sensor getar SW-420 untuk mendeteksi besar getaran yang terjadi, sensor Accelerometer adxl335 untuk mendeteksi posisi dan gerak permukaan dengan sumbu X, Y, dan Z, serta dilengkapi dengan database mysql dan firebase sebagai wadah data untuk sistem informasinya.
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Rebeka Firsly Stephanie Harianja, Lili Rusdiana, and Catharina Elmayantie
- Sistemasi: Jurnal Sistem Informasi, Vol 12, Iss 1, Pp 70-78 (2023)
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Technology, Information technology, and T58.5-58.64
- Abstract
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As technology develops, the use of vending machines also develops. In addition to purchasing food and drinks, it can also be used to exchange medicine packaging for coins. To simplify the exchange process to make it more practical and not to spend a lot of time, a reverse vending machine was built for drug packaging containing metal as input. Collecting data using the method of observation and literature study. This type of research is prototyping because the results obtained are in the form of a prototype. This prototype used 3 buttons in main process. The first stage is pressing button 1 to detect metal, then pressing button 2 to weigh, and button 3 to release coins. The test results obtained from the Arduino-Based Reverse Vending Machine Metal Medicine Packaging Exchange indicate that the prototype is able to be used as a medium of exchange for drug packaging trash containing metal into a medium of exchange in money form. The prototype is able to provide a solution for reducing or managing medical trash which contains metal.
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72. Innover dans les forces spéciales [2023]
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Jean Frances and Violette Larrieu
- Socio, Vol 17, Pp 161-185 (2023)
- Subjects
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innovation logic and organisation logic, innovation by and for operational personnel, Special Forces, military equipment, “something on the side”, combatant work, and Social Sciences
- Abstract
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How do military personnel succeed in designing or perfecting equipment useful to their mission? This paper will analyse the production of material innovations that are characterised by their ability to respond to an operational need, whose design is based on the skills, resources and abilities of soldiers in the field, and whose modelling and prototyping do not require the deployment of major research and development resources. We will show that these activities are based on an inverted form of “something on the side”. More generally, the question arises as to the capacity of an institution marked by the rigour of its hierarchy to make accessible to its personnel the margins of autonomy necessary for the engagement of frugal forms of technological research and development. Through an analysis centred on two case studies—a grenade-launching pole and an oxygen mask for dogs—of innovation by and for Special Forces operatives, we highlight the difficulty, for the military institution, of making an ‘innovation logic’ coexist with an ‘organisation logic’ and articulating them.
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Juliana Kurek, Luciana Londero Brandli, Marcos Antonio Leite Frandoloso, Amanda Lange Salvia, and Janaina Mazutti
- Sustainability, Vol 15, Iss 988, p 988 (2023)
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sustainability, innovation, innovative sustainable business models, design thinking, framework, Environmental effects of industries and plants, TD194-195, Renewable energy sources, TJ807-830, Environmental sciences, and GE1-350
- Abstract
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The process of integrating sustainability into businesses and processes is still recent, both in startups, small and medium-sized companies and even multinationals. Sustainable business models became a phenomenon of global interest and Design Thinking has been increasingly used as a strategy to support this process. In this context, the aim of this article is to improve the understanding of how Design Thinking (DT) and its set of tools and methods contribute to the creation and innovation of sustainable business models (SBM). The analysis of frameworks indicates that the main methodologies linking Design Thinking and Sustainable Business Models are Workshops, Brainstorming, Co-creation and Prototyping. Also, approaches such as Circular Economy, Business Models and Product-Service System models are emerging as a means of enabling the collaborative consumption of products and services and with positive results for sustainable business. The analysis of the articles reveals that user-oriented innovation and analysis of stakeholder needs is present in practically all evaluated frames, but prototyping and experimentation represent a gap that should be better explored in the frameworks.
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Georgi V. Georgiev and Vijayakumar Nanjappan
- Sustainability, Vol 15, Iss 1519, p 1519 (2023)
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digital fabrication, design education, prototyping, FabLab, makerspace, sustainability education, Environmental effects of industries and plants, TD194-195, Renewable energy sources, TJ807-830, Environmental sciences, and GE1-350
- Abstract
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Design education utilising digital fabrication is characterised by a dynamic project-based learning environment in which ideas are embodied in prototypes. This environment affects the way design and fabrication activities are taught, including sustainability considerations in the process and the outcomes. With the objectives of refining the sustainability indicators in the context of digital fabrication design education and identifying educational interventions for improving sustainability, we analyse the processes and outcomes of a digital fabrication course. We further develop a conceptual framework for sustainable prototyping based on the prototyping and testing stages in the design thinking model. The sustainability considerations in the prototyping process and outcomes in the design education context in FabLab are exemplified. The findings will help enhance sustainability and develop interventions in the context of design education.
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75. Are educational robots any good for communicative English learning for primary school students? [2023]
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Xiaotong Yu, Maria Angeles Gutierrez-Garcia, and Roberto Soto-Varela
- Texto Livre: Linguagem e Tecnologia, Vol 16 (2023)
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Robot-assisted English learning, Communicative English learning, Exploratory prototyping, Rapid prototyping, Technology, and Language and Literature
- Abstract
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This paper presents a pilot study that focuses on the exploratory and rapid prototyping within the human-in-the-loop control of a self-constructed and developed educational robot in assisting communicative English learning in primary Education in Madrid, Spain. The study sample was composed of 37 3rd graders that attended four English learning program sessions in November 2021, in which robot integration plays a leading role as learning material. To achieve the above, an easy-to-build, programmed and economical LEGO Education Mindstorms EV3 package was optioned. Pre-and-post questionnaires, classroom observations, and an evaluation sheet that measures self-evaluation, peer evaluation, and teacher evaluation were applied. The result reveals students’ perception of the pioneering robot and although preliminary, presents validation of the technology for English class assistance. Another finding suggests that students’ stress generated from communication in English among peers was reduced with the companion of the robot. Due to the nature of a pilot study, both the number of sessions and the sample size are limited to determine if the robot is helpful in students’ vocabulary acquisition in the long run. Further study is to be conducted with the pioneer model to teach vocabularies of different categories for a longer period. The findings of this pilot study will serve as a reference in the attempt to develop and reproduce promising robots to assist English teaching and learning that are accessible to public schools.
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76. Geometrical analysis in material extrusion process with polylactic acid (PLA)+carbon fiber [2022]
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Bermudo Gamboa, Carolina, Martín Béjar, Sergio, Trujillo Vilches, Francisco Javier, and Sevilla Hurtado, Lorenzo
- Rapid Prototyping Journal, 2022, Vol. 29, Issue 11, pp. 21-39.
77. Multimaterial powder bed fusion techniques [2022]
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Mehrpouya, Mehrshad, Tuma, Daniel, Vaneker, Tom, Afrasiabi, Mohamadreza, Bambach, Markus, and Gibson, Ian
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 1-19.
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Dämmer, Gabriel, Bauer, Hartmut, Neumann, Rüdiger, and Major, Zoltan
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 20-32.
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Kolb, Cara Greta, Lehmann, Maja, Kriegler, Johannes, Lindemann, Jana-Lorena, Bachmann, Andreas, and Zaeh, Michael Friedrich
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 33-50.
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Graziosi, Serena, Ballo, Federico Maria, Libonati, Flavia, and Senna, Sofia
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 51-64.
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Chacón, Jesús Miguel, Sánchez-Reyes, Javier, Vallejo, Javier, and Núñez, Pedro José
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 65-76.
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Ren, Diqian, Choi, Jun-Ki, and Schneider, Kellie
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 77-91.
83. Shrinkage behaviour of material extrusion steel 316L: influence of primary 3D printing parameters [2022]
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Obadimu, Solomon O. and Kourousis, Kyriakos I.
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 92-101.
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Bricín, David, Véle, Filip, Jansa, Zdeněk, Špirit, Zbyněk, Kotous, Jakub, and Kubátová, Dana
- Rapid Prototyping Journal, 2022, Vol. 28, Issue 11, pp. 102-122.
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Yi, Hwang
- Engineering, Construction and Architectural Management, 2021, Vol. 29, Issue 10, pp. 4132-4152.
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Anders Kalsgaard Møller, Camilla Finsterbach Kaup, Eva Brooks, Dorina Gnaur, Maja Højslet Schürer, and Marie Charlotte Lyngbye
- Acta Didactica Norden, Vol 16, Iss 4 (2022)
- Subjects
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computationel tankegang, videregående uddannelse, humaniora, programmering, Special aspects of education, and LC8-6691
- Abstract
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Med udgangspunkt i det stigende behov for IT-kompetencer er de humanistiske universitetsuddannelser begyndt at indføre kurser, der skal styrke de studerendes forståelse for informatik. Denne artikel undersøger, hvordan studerende på en masteruddannelse i IT på et humanistisk fakultet udvikler kompetencer i programmering og computationel tankegang. De studerende havde alle et obligatorisk kursus i Programmering og Prototyping, og nogle af dem havde valgfag i Computational Thinking. Data består af observationer fra kurserne, vurdering af de studerendes opgaver og fire fokusgruppeinterviews. (De studerende var delt i to grupper – en med Computational Thinking og den anden med kun Programmering og Prototyping.) Vi afholdt interviews før og efter kurserne for begge grupper for at afdække, hvordan elevernes synspunkter havde ændret sig. Begge grupper af studerende ser sig selv i koordinerende roller, hvor de samarbejder med programmører og andre softwareudviklere. De studerende der valgte valgfaget i Computational Thinking, viste et rigere ordforråd, når de beskrev computationel tankegangs begreber, praksisser og perspektiver. Evnen til at reflektere over de praktiske opgaver, herunder begreber, praksisser og perspektiver, synes essentiel for de studerendes fremtidige karriere, som humanister, der arbejder med teknologi. Resultaterne viser, hvordan studerende kan udvikle deres forståelse af computationel tankegang med stilladsering mod computational empowerment. I processen så vi, hvordan studerende opnår en forståelse af computationel tankegang gennem arbejde med koncepter og praksisser, og hvor der opstod perspektiver ved at kombinere computationel tankegang med information og praksis fra andre discipliner.
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A. C. de Mendonça, D. K. K. Cavalcanti, H. F. M. de Queiroz, J. S. S. Neto, F. J. P. Chaves, and M. D. Banea
- Annals of "Dunarea de Jos" University of Galati, Fascicle XII, Welding Equipment and Technology, Vol 33, Iss 1, Pp 27-34 (2022)
- Subjects
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additive manufactured parts, abs, fillers, mechanical properties, Technology, Mining engineering. Metallurgy, and TN1-997
- Abstract
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Rapid prototyping (also known as additive manufacturing, AM) is a quickly developing process with increasing new applications in a large variety of industrial sectors (i.e., aerospace, automotive, medical, among others.) However, despite the great advantage of a decoupled price to part complexity of an AM fabricated structure, the material properties (largely governed by filament material and printing parameters) still present a significant limiting factor. In this context, the development of new filament materials for a wider range of applications has great potential. In this study, the influence of micro-scale filler reinforcement (powders), both natural (curauá) and synthetic (glass fibre), in the fabrication of an Acrylonitrile Butadiene Styrene (ABS) filament was evaluated. The filler was controlled by weight fraction (~1%) and the filament was fabricated via extrusion. A commercially available 3D printer was used to print tensile and flexural specimens for mechanical characterization as per ASTM standards. The fracture morphology was analysed after tensile testing via optical microscopy in order to evaluate the effect of the fillers on the material deposition and void formation. No significant variation in the tensile properties was reported, except for the strain at failure, while more significant flexural strength variation was observed as a function of filler material. The fillers presented a significant effect on the void density of the fractured surface. It was demonstrated that this simple fabrication technique can generate novel filament materials that may enhance the mechanical properties or widen the range of application (e.g., faster decomposition times in nature for single-use plastics due to the hydrophilic nature of the natural filler and lower water absorption of the hydrophobic synthetic filler for marine environment applications).
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88. NUMERICAL AND EXPERIMENTAL ANALYSIS OF A CENTRIFUGAL PUMP WITH DIFFERENT ROTOR GEOMETRIES [2022]
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Łukasz SEMKŁO and Łukasz GIERZ
- Applied Computer Science, Vol 18, Iss 4, Pp 82-95 (2022)
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pump, cfd, the head of the pump, power, efficiency, Information technology, T58.5-58.64, Electronic computers. Computer science, and QA75.5-76.95
- Abstract
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The paper presents a comparative analysis of the operation of two variants of centrifu-gal pump rotors, a description of the main parameters, and the influence of the blade geometry on the performance characteristics obtained. Rotors have been designed using the arc and point method. Based on the developed 3D CAD models, the rotors were printed using the rapid prototyping method on a 3D printer in FFF (Fused Filament Fabrication) technology, in order to experimentally verify the performance, by placing them on the Armfield FM50 test stand. The analysis part of the CFD includes a fluid flow in Ansys Fluent. The process of creating a flow domain and generating a structural mesh was described, along with the definition of boundary conditions, the definition of physical conditions and the turbulence model. The distribution of pressures and velocities in the meridional sections is shown graphically. The chapter with the experimental analysis contains a description of the measuring stand and the methodology used. The results obtained made it possible to generate the characteristics, making it possible to compare the results received. The results allowed to note the influence of geometry on the behavior of the rotors during operation in the system and to indicate that the arc rotor gets a 7% higher head and 2% higher efficiency than the point method rotor, which gives the basis for its commercial use in industry.
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Adam Muc, Agata Bielecka, and Jan Iwaszkiewicz
- Applied Sciences, Vol 13, Iss 532, p 532 (2022)
- Subjects
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wireless control, thyristor rectifier, IoT, Arduino, NodeMCU, Bluetooth, Technology, Engineering (General). Civil engineering (General), TA1-2040, Biology (General), QH301-705.5, Physics, QC1-999, Chemistry, and QD1-999
- Abstract
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The paper presents the implementation possibilities of remote control by use of wireless communication and mobile application dedicated to controlling systems of power electronics converters. The article focuses on Bluetooth and Wi-Fi technologies as they are currently the most commonly used in modern mobile devices. The authors wanted to check the usefulness of those methods in the application of a classic drive set with a DC motor. The MIT App Inventor programming environment, which allows quick prototyping of the mobile graphical interface, was used to develop the mobile application. The developed prototype of the mobile application is the second thread of the article, the aim of which is to propose a mobile application interface that enables safe control of the electric drive in an open loop. By repeated testing of the graphical structure of the application and the controls used, the authors obtained the final form of the interface, which, in their opinion, is absolutely required when developing such programs. The evaluated control strategy has been also used to control the rotational speed of a permanent magnet DC motor supplied by a three-phase thyristor rectifier. This paper’s research results have shown the proposed solutions’ advantages and disadvantages.
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José Neres de Almeida Junior, Orlando Rodrigues Junior, and Maria da Penha Albuquerque Potiens
- Brazilian Journal of Radiation Sciences, Vol 10, Iss 3B (2022)
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Additional Filtration, Diagnostic Radiology, 3D Printing, Prototyping, Calibration., and Science
- Abstract
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The Calibration Laboratory (LCI) of the Nuclear and Energy Research Institute (IPEN-/CNEN) offers calibration services for radiation measurements instruments used in radiation protection, diagnostic radiology and radiotherapy. LCI produces radiation qualities and irradiation conditions which are in accordance with the national and international standard requirements. In order to establish the recommended radiation qualities for diagnostic radiology, X-ray beams generated in laboratory are modified for the irradiation conditions found in equipment routinely used in healthcare services. In this work, a new additional filtration system was developed to be adapted to the existing filter system at LCI. The new filter support can be coupled to the PTW Bench Control installed at the LCI X-ray system. Using a FDM 3D printer, a support model and a set of drawers were developed for the placement of additional filters. The models were also developed to fit each specific drawer of each filter to be used in the laboratory routine, coupled to the specific sensors that fit the spaces of the support part. Additionally, a microcontroller based on Arduino, micro switches, low- and high-level programming, allow checking of drawer status and integration of information with the laboratory control system. The system allows the recognition of the filter inserted in the drawer from sensors attached to the support. Tests were carried out to verify the usability of the system in the routine, adding Ag (silver) and Cu (copper) filters, for the characterization of attenuated radiation beams of interest in diagnostic radiology.
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Amer A. Hijazi, Srinath Perera, Ali M. Alashwal, and Rodrigo N. Calheiros
- Buildings, Vol 13, Iss 91, p 91 (2022)
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BIM, blockchain, construction supply chain, single source of truth, software prototype, Building construction, and TH1-9745
- Abstract
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Blockchain technology has been proposed as a potential solution for coordinating information and trust to aid the development of a single source of the truth data model, going beyond peer-to-peer cash transactions. It is, therefore, argued that the construction supply chain (CSC) will resolve issues related to the lack of reliable platforms for construction and asset management operations once blockchain technology and Building Information Modelling (BIM) are integrated. Though there is no longer any debate about the importance of integrating blockchain technology with BIM, there is still a lack of academic literature on its proof of concept. This study aims to create a thorough proof of concept for integrating blockchain technology and BIM for supply chain data delivery. It demonstrated a step-by-step methodology starting from understanding the current business scenario and proposing logical system architecture, followed by selecting a blockchain platform, designing system architecture related to technologies, prototyping, and evaluating through a virtual business scenario. The software prototype presented in this paper helps establish the technological viability of a single source of the truth data model for integrating blockchain technology and BIM. The supply chain data delivery for handover was considered in this software prototype. However, the process used to create this software prototype can be replicated in future work on blockchain technology-based built environment applications or digital transformation in the built environment research.
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Wentao Li, Natalie Baddour, and Edward Lemaire
- Canadian Prosthetics & Orthotics Journal, Vol 5, Iss 2 (2022)
- Subjects
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Ankle Foot Orthosis, Dynamic Gait Rehabilitation, Multi-Stiffness Ankle Foot Orthosis, Quick Release, Orthosis, Medical technology, R855-855.5, Orthopedic surgery, and RD701-811
- Abstract
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BACKGROUND: A posterior dynamic element ankle-foot orthosis (PDEAFO) uses a stiff carbon fibre strut to store and release energy during various mobility tasks, with the strut securely attached to the foot and shank-cuff sections. A design that allows the user to swap struts for specific activities could improve mobility by varying PDEAFO stiffness, but current approaches where bolts securely connect the strut to the orthosis make quick strut swapping time-consuming and impractical. OBJECTIVES: Design a novel quick release AFO (QRAFO) that can enable daily living strut-swapping and thereby enable better ankle biomechanics for the person’s chosen activity. METHODOLOGY: The novel QRAFO enables device stiffness changes through a quick release mechanism that includes a quick-release key, weight-bearing pin, receptacle anchor, and immobilization pin. A prototype was modelled and simulated with SolidWorks. Mechanical tests were performed with an Instron 4482 machine to evaluate quick release mechanism strength with running and 20° slope downhill walking loads. Quick release efficiency was then evaluated via two quick release functional tests, with four participants wearing a 3D printed QRAFO. FINDINGS: Simulated stress on the weight bearing pin, anchor, and surrounding carbon fibre structure under running and downhill walking loads did not exceed the yielding stress. Mechanical tests verified the simulation results. Four participants successfully swapped the strut within 25.01 ± 3.66 seconds, outperforming the 60.48 ± 10.88 seconds result for the hand-tightened bolted strut. A learning evaluation with one participant showed that, after approximately 30 swapping iterations, swap time was consistently below 10 seconds. CONCLUSION: The quick release mechanism accommodated running and slope walking loads, and allowed easy and fast strut removal and attachment, greatly reducing strut swap time compared to screw-anchor connections. Overall, the novel quick release AFO improved strut-swapping time without sacrificing device strength, thereby enabling people to use the most appropriate AFO stiffness for their current activity and hence improve mobility and quality of life. Layman's Abstract An advancement in ankle foot orthosis (AFO) design, named Posterior Dynamic Strut AFO (PDEAFO), securely attaches a strut to the foot and shank-cuff sections via bolts, to better match a user’s activity level. The PDEAFO design approach makes quick strut swapping impractical. A novel quick release PDEAFO design was created to enable AFO users to quickly switch struts when desired, therefore enabling better ankle biomechanics for the person’s chosen activity. The novel quick release AFO (QRAFO) includes a quick-release key, weight-bearing pin, receptacle anchor, and immobilization pin. To ensure appropriate QRAFO strength, simulated loads were tested before prototyping. The prototype was mechanical testing under maximum loads. To prove quick release mechanism efficiency, the author conducted controlled experiments between screw-anchor mechanism (used by PDEAFO) and quick release mechanism on 3D printed AFOs. Simulations demonstrated safe performance under walking, running, and downhill walking conditions. Mechanical testing proved component strength under maximum loads. Functional testing showed that participants can swap struts within 25.01± 3.66 seconds on the quick release AFO, outperforming the 60.48 ± 10.88 seconds result for the screw anchor mechanism. In conclusion, the quick release AFO improved strut-swapping time without sacrificing device strength, thereby enabling people to use the most appropriate AFO stiffness for their current activity and hence improve mobility and quality of life. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/38802/30399 How To Cite: Li W, Baddour N, Lemaire E.D. A novel quick release mechanism for ankle foot orthosis struts. Canadian Prosthetics & Orthotics Journal. 2022; Volume 5, Issue 2, No.3. https://doi.org/10.33137/cpoj.v5i2.38802 Corresponding Author: Edward D. Lemaire, PhD Centre for Rehabilitation Research and Development, Ottawa Hospital Research Institute, Ottawa, Canada. E-Mail:elemaire@ohri.ca ORCID ID: https://orcid.org/0000-0003-4693-2623
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93. Design-driven entrepreneurship: a cooking exercise to integrate effectuation and design thinking [2022]
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Kevin James and Luca Iandoli
- CERN IdeaSquare Journal of Experimental Innovation, Vol 6, Iss 2 (2022)
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creativity, aesthetics, effectuation, design, ideation, new product development, Technology (General), T1-995, Technological innovations. Automation, and HD45-45.2
- Abstract
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This paper presents an experiential learning exercise to (a) Provide students with an effective analogy of the way entrepreneurs identify opportunities and solve problems in the development of new products, (b) Help them to reflect on the importance of defining a Creative Workflow in entrepreneurial endeavors, and (c) Encouraging students to practice Empathy. The proposed exercise is built on using cooking as a metaphor for design-driven innovation. The exercise design is grounded on effectuation, human-centered design, and pedagogic approaches relying on co-creation and prototyping (Aalto Design Factory, 2017). The exercise was created during the pandemic as part of a broader attempt to migrate an entrepreneurship course online. Since the course intensively used prototyping and design exercises, there was a need to find effective ways to transfer these teaching experiments to a virtual environment. The exercise was demoed to academic instructors during a virtual international conference on design-driven innovation. The experts’ feedback and reactions were collected through the video recording of the session and follow-up conversations. This paper will present the exercise in detail, lessons learned, and reflections extracted from the demo session.
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Sara Figueiredo, Apurva Ganoo, Vikki Eriksson, and Kalevi Ekman
- CERN IdeaSquare Journal of Experimental Innovation, Vol 6, Iss 2 (2022)
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experiential learning, product development, Interpersonal skills, multidiciplinary Education, Technology (General), T1-995, Technological innovations. Automation, and HD45-45.2
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This paper addresses the learning outcomes and student perceptions of the Aalto University PdP course, which promotes experiential learning and where multidisciplinary master student teams work on industry-based projects. These outcomes were collected through a questionnaire filled by students voluntarily, which focussed on what were the main competencies, where they were acquired and what was the core learning. The results highlight the significance of interpersonal skills, which formed the most significant category reported by students, and were perceived as critical for project success. Furthermore, the study highlights the importance of the multifaceted role that prototyping plays in communication and sense-making.
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Remigiusz Wiśniewski, Marcin Wojnakowski, and Zhiwu Li
- Energies, Vol 16, Iss 67, p 67 (2022)
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modelling, verification, boundedness, error detection, real-life CPS, FPGA, and Technology
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This paper presents a novel design approach of a Petri-net-based cyber-physical system (CPS). The idea is oriented toward implementation in a field-programmable gate array (FPGA). The proposed technique permits error detection in the system at the early specification stage in order to reduce the time and prototyping cost of the CPS. Due to the state explosion problem, the traditional verification methods have exponential computational complexity. In contrast, we show that under certain assumptions, the proposed algorithm is able to detect possible errors in the system even in cubic O(|T|2|P|) time. Furthermore, all the required steps of the proposed design method are presented and discussed. The idea is illustrated by a real-life case study example of a traffic light crossroad. The system was modelled, analysed, implemented, and finally validated within the FPGA device (Virtex-5 family).
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Jonas Vedsted Sørensen, Zheng Ma, and Bo Nørregaard Jørgensen
- Energy Informatics, Vol 5, Iss S4, Pp 1-30 (2022)
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Digital twin, Wind energy, Game engine, Unreal Engine, Simulation, Energy industries. Energy policy. Fuel trade, and HD9502-9502.5
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Abstract Digital twin technologies have become popular in wind energy for monitoring and what-if scenario investigation. However, developing a digital representation of the wind is challenging, especially due to the digital twin platform constraints. Game engines might be possible to solve this issue, especially since game engines have been used for product design, testing, prototyping, and also digital twins. Therefore, this study investigates the potential of developing a digital twin of wind power in the Unreal game engine. A case study of two types of wind turbines (Vestas V164-8 and Enercon E-126 7.580) and one location (Esbjerg, Denmark) is chosen for this study. The digital twin includes the environment with historical wind data and the visual representation of the wind turbine with a wind power production model and the estimated production in the given wind conditions of the area. The results show that game engines are viable for building entire digital twins where a realistic graphical user interface is required. Unreal Engine 5 provides the tools for modelling the landscape, surrounding water, and lighting. In addition, the Unreal Engine ecosystem provides vast amounts of content, such as 3D assets and game logic plugins, easing the digital twin development. The results prove that digital twins built in Unreal Engine 5 have great potential development of digital twins and user interfaces for communicating with a digital twin. The developed digital twin allows for further extension to benefit future digital twins utilizing wind turbines.
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Christopher Heuer, John‐Alexander Preuß, Taieb Habib, Anton Enders, and Janina Bahnemann
- Engineering in Life Sciences, Vol 22, Iss 12, Pp 744-759 (2022)
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3D printing, biosensors, cell culture, microfluidics, miniaturization, Biotechnology, and TP248.13-248.65
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Abstract Since its invention in the 1980s, 3D printing has evolved into a versatile technique for the additive manufacturing of diverse objects and tools, using various materials. The relative flexibility, straightforwardness, and ability to enable rapid prototyping are tremendous advantages offered by this technique compared to conventional methods for miniaturized and microfluidic systems fabrication (such as soft lithography). The development of 3D printers exhibiting high printer resolution has enabled the fabrication of accurate miniaturized and microfluidic systems—which have, in turn, substantially reduced both device sizes and required sample volumes. Moreover, the continuing development of translucent, heat resistant, and biocompatible materials will make 3D printing more and more useful for applications in biotechnology in the coming years. Today, a wide variety of 3D‐printed objects in biotechnology—ranging from miniaturized cultivation chambers to microfluidic lab‐on‐a‐chip devices for diagnostics—are already being deployed in labs across the world. This review explains the 3D printing technologies that are currently used to fabricate such miniaturized microfluidic devices, and also seeks to offer some insight into recent developments demonstrating the use of these tools for biotechnological applications such as cell culture, separation techniques, and biosensors.
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L. Ferroni, E. Tremoli, S. Leo, B. Zavan, and C. Mortellaro
- European Review for Medical and Pharmacological Sciences, Vol 26 (2022)
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Therapeutics. Pharmacology and RM1-950
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Additive manufacturing (AM) has increasing applications in medicine in recent times. This technology has emerged in cardiovascular medicine as an intelligent system for the improvement of medical devices, the preparation of patient-specific models, and the prototyping of grafts. This review traces the research and development in the production of surgical guides and synthetic grafts for cardiac and vascular applications over the last few years. It also traces the recent widespread use of 3D-printed specific-patient models for cardiovascular surgical interventions. A current view of AM strategies, materials and solutions to improve cardiovascular patient outcomes is also provided.
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Danilo Santoro, Nicola Delmonte, Paolo Cova, and Andrea Toscani
- Frontiers in Energy Research, Vol 10 (2022)
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active load, power supply testing, cost-efficient, load emulation, fast prototyping, arbitrary current absorption, and General Works
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The increased use of DC renewable energy resources and DC storage systems, combined with the necessary reduction of energy waste, is boosting the development of DC smart grids. In this scenario, DC load emulation is of great importance. From the hardware point of view, DC buses stability of smart grids and the different DC/DC converter topologies must be tested. From the software point of view, smart grid strategies and job schedulers must be tested with different power absorption profiles. Moreover, DC load emulation can be useful for many other purposes, such as battery characterization, power supply testing, photovoltaic I-V curve measurements, etc. In this work, a cost-efficient DC Active Load (AL) solution is proposed. The principle of the circuit topology is a buck-boost-derived converter. This solution can be designed and tested considering the required voltage, current, and maximum input power. Both simulation and experimental results are shown on a 400 W size prototype. Thermal and electrical results validate the simulation model and the AL feasibility.
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Igor Zhilyaev, Stefan Grieder, Marco Küng, Christian Brauner, Michael Akermann, Jonas Bosshard, Petra Inderkum, João Francisco, and Martin Eichenhofer
- Frontiers in Materials, Vol 9 (2022)
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additive manufacturing, fiber-reinforced composites, additive fusion, consolidation, process-induced deformations, porosity evaluation, and Technology
- Abstract
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Substitution of conventional metal structures with fiber-reinforced polymers is possible because of their sustainable performance. One of the primary disadvantages of these composite materials is their high cost due to labor-intensive manufacturing. Because the fiber path can be steered directly along the load path, structures can be manufactured in a near-net shape, and a high degree of reproducibility with low scrap rates can be achieved. Additive manufacturing of these composite structures could enable cost efficiency with a high degree of complexity. However, the high degree of porosity and high void content between the printed fiber filaments results in unacceptable structural performance. Following the printing process, a post-consolidation process (additive fusion) can be performed to improve the mechanical performance of the part and use fiber-reinforced polymers for load-bearing applications. Numerical simulation of the consolidation process enables the production of these complex parts without expensive prototyping iterations. Because of the rapid and local changes in material stiffness, the simulation of the consolidation process is combined with a set of numerical model convergence problems. An advanced finite-element numerical model for simulating the consolidation process of additive manufactured continuous fiber composite parts is presented in this paper. The additive fusion step simulation allows for the evaluation of process-induced deformations, final engineering constants, and porosity. The simulation workflow is demonstrated and validated using experimental data from the manufacturing process of a typical aerospace part, specifically a helicopter hinge element.
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