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Collaborative and adaptive cyber Défense strategies, Healthcare networks, Cyber security edge computing, Cyber Défense strategies, Internet of Things, Computer applications to medicine. Medical informatics, and R858-859.7

The Internet of Things (IoT) is a massive network connecting various devices and computer systems. This technology makes prototyping and distributing cutting-edge software and services easier. Through specifically created healthcare networks, the IoT makes it simple to link digital and tangible devices. Disputes continue to arise in the industry due to the absence of uniformity and the rapid growth of products, services, and methods. This study seeks to provide a birds-eye perspective of the technologies and protocols that support the IoT’s foundation. We start by introducing an elaborate process to examine the function of healthcare networks in creating and disseminating IoT-based software and some solutions to the current problems. We then discuss and formulate future challenges and the unanswered concerns surrounding the IoT’s support for healthcare networks. The primary focus of this research is to dissect the IoT, or horizontal network, into its constituent parts. These elements are essential for creating secure and robust mobile applications.

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

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.

Phonon anisotropy, Heating effects, Temperature definition, Graphene, Monte Carlo method, Boltzmann equations, Engineering (General). Civil engineering (General), and TA1-2040

The effect of inclusion of the planar phonon anisotropy on thermo-electrical behavior of graphene is analyzed. Charge transport is simulated by means of Direct Simulation Monte Carlo technique coupled with numerical solution of the phonon Boltzmann equations based on deterministic methods.The definition of the crystal lattice local equilibrium temperature is investigated as well and the results furnish possible alternative approaches to identify it starting from measurements of electric current density, with relevant experimental advantages, which could help to overcome the present difficulties regarding thermal investigation of graphene.Positive implications are expected for many applications, as the field of electronic devices, which needs a coherent tool for simulation of charge and hot phonon transport; the correct definition of the local equilibrium temperature is in turn fundamental for the study, design and prototyping of cooling mechanisms for graphene-based devices.

Wireframe structures, Path planning, Additive manufacturing, Deformation processing, Industrial engineering. Management engineering, and T55.4-60.8

This paper presents a computer numerical control (CNC) deformation process, termed Bend-Forming, for fabricating 3D wireframe structures. The process relies on the combination of CNC wire bending with mechanical joints to construct reticulated structures from wire feedstock. A key component of the process is a path planning framework which uses Euler paths and geometrical computations to derive fabrication instructions for arbitrary 3D wireframe geometries. We demonstrate the process by fabricating exemplary structures on the order of 1 m, including reticulated columns, shells, and trusses, with rapid build times compared to other additive manufacturing techniques. The structures fabricated herein contain defects which result in residual stress and imperfect geometries. To determine the tolerances needed to fabricate accurate structures, we develop a model of error stack-up for Bend-Forming, using fabrication defects in feed length, bend and rotate angle, and strut curvature. We find that for tetrahedral trusses fabricated with Bend-Forming, defects in feed length and strut curvature have a large effect on the surface precision and stiffness of the truss, respectively, and are thus important tolerances to control to achieve structural performance metrics. Overall, Bend-Forming is a versatile and low-power process that is well suited for a wide-range of applications, from rapid prototyping of wireframe structures to in-space manufacturing.

Directed energy deposition, entropy, grain refinement, alloy design, Industrial engineering. Management engineering, and T55.4-60.8

Additive manufacturing (AM) is a tool for rapid prototyping with complex geometry. However, the cyclic heating and cooling in laser melting processes often cause large columnar grains that dominate the as-printed microstructure, resulting in a strong texture and anisotropic properties that limit the application of AM. In this work, we apply powder-based directed energy deposition to discover new alloys using mixtures of Inconel 718 (IN718) and Stainless Steel 316L (SS316L). We discovered that the 77 wt.% IN718 alloy mixture, with the highest configurational entropy, demonstrated an intriguingly fine grain structure in the as-built condition and after homogenization at 1180°C. Residual stress from the laser melting process was identified as the primary cause of the observed grain refinement phenomenon. Although, a quantitative analysis of the changes in grain size after homogenization in the alloy mixtures of IN718 and SS316L requires further research. The discovery of this unique microstructural behavior shows how in-situ mixing of commercially available powders can be used to develop next-generation feedstock materials for AM and improve the understanding of fundamental process-microstructure-property relationships.

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

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.

3D Bioprinting, Bioink, Printability, FDM, Carboxy methyl cellulose, Medical technology, and R855-855.5

Three dimensional (3D) bioprinting is a rapid prototyping technology that can be used to accurately position living cells and biomaterials called bioink, to fabricate functional living tissue constructs or organs. The bioink are deposited in 3D in a layer-by-layer manner using a bioprinter. However, commercially available 3D bioprinters are expensive, limiting the widespread adoption of this technology in low-resource laboratories. To overcome this limitation the conventional Filament Deposition Modelling (FDM) 3D printer can be modified to a 3D bioprinter by replacing the print head unit. During the makeover, The device has to perform in its most efficient capacity in synergy with the bioink used. Hence it is essential to check the bio-printabililty of bioink in the modified FDM printer. In this study we created certain specific G-codes for the evaluation of hybrid bioinks and authenticated the printability. This study focuses on quantifying the printability of a hybrid hydrogel composed of sodium salt carboxymethyl cellulose (CMC) and gelatin using a 3D bioprinter based on the RepRap prototyper. The 3D design and slicing parameters were generated using opensource software and manually edited for printability evaluation. The results of these experiments indicate the importance of printability evaluation of custom bioprinters and provide some key aspects of how to modify CAD design parameters for printability evaluation. This approach can also be adopted to evaluate the printability of other hydrogels for bio-printing. The codes are created to evaluate the printability of bioink using FDM modified bioprinters. The printability evaluation is limited to high viscous bioink for extrusion bioprinting. A user friendly, simple G-Codes and methodology for evaluation of printability of bioink using FDM modified bioprinters. To authors knowledge, this is the first report on 3D printability evaluation of bioink using FDM modified bioprinters. The study also fulfills an identified need to study printability of bioink in biofabrication by additive manufacturing.

Power electronics, Inverters, Rapid control prototyping, Experimental setups, Science (General), and Q1-390

A flexible power electronic converter embedding a rapid control prototyping platform suitable to be applied in research test setups and teaching laboratories is proposed and described in this paper. The electronic system is composed of three subsystems, namely, i) three half-bridge power boards, ii) a dc-link capacitor bank with a half-bridge power module for active dc-link control, iii) an interfacing board, called motherboard, to couple the power modules with a control unit, iv) a digital control unit with rapid control prototyping functionalities for controlling power electronic circuits. Power modules integrate sensors with related conditioning circuits, driving circuits for power switches, and protection circuits. Conversion circuits exploit GaN electronic switches for optimal performance. The architecture and implementation of the system are described in detail in this manuscript. Main applications are in the implementation of conversion circuits for supplying arbitrary ac or dc voltages or currents, testing of new control algorithms for power electronic converters, testing of systems of electronic converters in, for example, smart nanogrids or renewable energy applications, training of undergraduate and graduate students.

Superhydrophobic, Reentrant structures, Wenzel state, Cassie-Baxter state, Two-photon polymerization, 3D printing, Electronics, TK7800-8360, Technology (General), and T1-995

In this work, we fabricate a hexagonal array of pillars where each pillar has a “micro-hoodoo” shape, i.e., a reentrant cross section. The shape of the pillars makes them more resilient towards total wetting, i.e., transition from a Cassie-Baxter non-wetting state to a Wenzel wetting state. We show the single-step fabrication of 4 × 4 mm2 arrays by two-photon polymerization direct laser writing of the polydimethylsiloxane (PDMS)-derived commercial resin IP-PDMS. The use of a hydrophobic resin for rapid prototyping of reentrant structures enables the fabrication of surfaces patterns displaying superhydrophobic behavior despite the use of relatively simple structures, i.e. with a single reentrant surface. By changing the size of the micro-hoodoos and the packing density of the arrays, we map wetting behaviors ranging from the pinning of water droplets in Wenzel state to non-wetting Cassie-Baxter states. The measured contact angles follow quite well the theoretical results obtained by minimizing Gibbs free energy using the Wenzel, Cassie-Baxter and partial wetting theories. Among the tested micropatterns, five exhibited superhydrophobic properties, with a static contact angle with water as high as 158.1° ± 7.1°. This is the first demonstration of superhydrophobic surfaces produced by two-photon polymerization direct laser writing of PDMS in a single-step process.

Additive manufacturing, Two-photon, Direct laser writing, Photolithography, 3D microscopy, SU-8, Electronics, TK7800-8360, Technology (General), and T1-995

Multifocus gratings (MFGs) enable microscopes and other imaging systems to record entire Z-stacks of images in a single camera exposure. The exact grating shape depends on microscope parameters like wavelength and magnification and defines the multiplexing onto a grid of MxN Z-slices. To facilitate the swift production and alteration of MFGs for a system and application at hand, we have developed a fabrication protocol that allows manufacturing of 1xN MFGs within hours and without the requirement of clean room facilities or hazardous etching steps. Our approach uses photolithography with a custom-built stage-scanning direct laser writing (DLW) system. By writing MFG grating lines into spin-coated negative tone SU-8 photoresist, polymerized parts are crafted onto the substrate and thus directly become a part of the grating structure. We provide software to generate the required MFG grating line paths, details of the DLW system and fully characterize a manufactured MFG. Our produced MFG is 5.4 mm in diameter and manages to record an image volume with a Z-span of over 600 μm without spherical aberrations or noticeable loss of resolution.