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RAPID prototyping, ROTATIONAL motion, DETECTORS, DIELECTRIC materials, MICROWAVES, and PROXIMITY detectors

This article presents a novel sensor for detecting and measuring angular rotation and proximity, intended for rapid prototyping machines. The sensor is based on a complementary split-ring resonator (CSRR) driven by a conductor-backed coplanar waveguide (CBCPW). The sensor has a planar topology, which makes it simple and cost-effective to produce and accurate in measuring both physical quantities. The sensor has two components, a rotor and a stator: the first of these (the CSRR) can rotate around its axis and translate along the plane normal to the ground of the CBCPW. A detailed theoretical and numerical analysis, along with a circuit model, of the unique sensor design is presented. The proposed sensor exhibits linear response for measuring angular rotation and proximity in the range of 30°–60° and 0–200 μm, respectively. Another distinctive feature of the rotation and proximity sensor is the wide frequency band of applicability, which is an integral part of its novel design and is implemented through various dielectric material loadings on the CSRR. In the prototype of the proposed device, the stator (CBCPW) is fabricated on a 0.508-mm-thick RF-35 substrate, whereas the CSRR-based rotor is fabricated on TLY-5 and RF-35 substrates. The angular rotation, proximity, operating band selection, and sensitivity are measured using a vector network analyzer and are found to be good matches to the simulated and theoretical results. [ABSTRACT FROM AUTHOR]

RAPID prototyping, TECHNOLOGY, SEMICONDUCTOR devices, and INTERPOLATION

In this paper, a new look-up table (LUT) method is proposed to reduce the simulation time and the run time memory requirement for large logic and mixed signal simulations. In the proposed method, for the first time, circuit with multiple devices is replaced by one LUT model, called circuit LUT. The replacement results in significant reduction of the run time memory requirement. The replacement also reduces the number of interpolation steps to be performed at every Newton–Raphson iteration during the simulation that results in significant reduction of simulation time. With the proposed method, the simulation speed is improved by two times over the conventional LUT models developed for devices. In addition, 25% reduction in the run time memory requirement is also achieved by the proposed method. [ABSTRACT FROM AUTHOR]

RAPID prototyping, USER interfaces, WIRELESS communications, RAPID tooling, TOYS, ACQUISITION of data, and MODULAR construction

• Compares two manufacturing strategies for Rapid Prototyping Tools. • One tool is a single board, while the other combines modular and plug-and-play strategies. • We embedded both tools into smart toy components of different shapes and sizes. • Modular approach offers better adaptability for different setups. • Technical assessment supports to list improvements for future versions of the tool. A Toy User Interface (ToyUI) is a setup that combines smart toy components with other hardware and software components to enhance the player's experience. We propose a novel Rapid Prototyping Tool to facilitate the development of smart toy components so that creative teams can focus on design improvements. IoT4Fun is a hardware toolkit that supports distributed data collection through wireless communication and contactless identification. It can support a range of play and interface features and limit personal data acquisition by collecting motion tracking information. We compare IoT4Fun single and modular toolkits by embedding them into ToyUI prototypes. The modular toolkit demonstrates more appropriate than the single-board version to design a variety of smart toy components when embedded into different shapes and sizes. A technical assessment compares battery consumption and identifies vulnerabilities of the modular toolkit. Ongoing improvements cover miniaturization, robustness, and designing a secure Application Programming Interface for easier development. [ABSTRACT FROM AUTHOR]

RAPID prototyping, DECISION making, ANALYTIC hierarchy process, GREY relational analysis, FUZZY numbers, and STRENGTH of materials

A multitude of rapid prototyping (RP) systems and technologies have come up since the introduction of additive process. Owing to the enlarging number of these systems with distinctive efficacy, the problem of selecting an appropriate system for a particular requirement is a cumbersome task. Henceforth, this work comes up with a strategy based on multi-attribute decision making to select a most suitable RP system. The presence of subjectivity in decision making as well as the existence of imprecision from various sources emphasize the methods which must consider uncertainty and vagueness. A decision advisor based on uncertainty theories, including fuzzy analytical hierarchy process (FAHP) and grey relational analysis (GRA) has been introduced. It provides a comprehensive database comprising thirty nine commercially available RP systems. The evaluation attributes consisting of machine cost, accuracy, layer thickness, machine speed, material cost, net build size volume, machine weight, surface roughness, and material strength were utilized to characterize the different machines. The FAHP based on trapezoidal fuzzy number was implemented to determine the priority weights of various attributes, while the GRA was employed to realize the best RP system and technology. The authors believe that this system has the potential to transform into a fully developed RP selection system. [ABSTRACT FROM AUTHOR]

WIRELESS power transmission, RAPID prototyping, RADIO frequency, GOLD coatings, and STAINLESS steel

This article presents an electromagnetically powered stent designed for hyperthermia treatment of in-stent restenosis. The stent device based on medical-grade stainless steel serves as a radio frequency (RF) inductive receiver to produce mild heating wirelessly through resonant-coupling power transfer, while acting as a mechanical scaffold inside an artery similar to commercial stents. The device and its custom transmitter are prototyped and optimized to show efficient wireless power transfer and stent heating through in vitro tests. The inductive stent with its helical pattern is gold coated to achieve a $3.5\times $ higher quality ($Q$) factor, improving heating performance of the device. The combinational use of independent resonant antennas with the power antenna is found to significantly boost stent temperature by up to 96% with an intermediate tissue layer. Upon matching the frequencies at which the $Q$ factors of the inductive stent, power antenna, and booster antenna are peaked, the stent excited through 10 mm-thick tissue exhibits a temperature increase of 18 °C, well over a necessary level for targeted hyperthermia treatment. The prototype achieves heating efficiencies (HEs) of 15.5–3.2 °C/W with a tissue thickness of 5–15 mm. These results indicate that the proposed resonant-heating stent system with the prototyped transmitter is promising for further development toward its clinical application. [ABSTRACT FROM AUTHOR]

RAPID prototyping, CURRENT-voltage characteristics, and ELECTRONIC feedback

Using a photovoltaic (PV) emulator (PVE) simplifies the testing of the PV generation system. However, conventional controllers used for PVEs suffer from oscillating output voltage, requiring a high number of iterations, or being too complex to be implemented. This paper proposes a controller based on a resistance feedback control strategy that produces a stable and fast converging operating point for the PVE. The resistance feedback control strategy requires a new type of PV model, which is the current–resistance (I–R) PV model. This model is computed using a binary search method at a fast convergence rate. It is combined with a closed-loop buck converter using a proportional-integral controller to form the resistance feedback control strategy. The PVE's controller is implemented into dSPACE ds1104 hardware platform for experimental validation. The acquired experimental results show that the proposed PVE is able to follow the current–voltage characteristic of the PV module accurately. In addition, the PVE's efficiency is more than 90% under maximum power point operation. The transient response of the proposed PVE is similar to the PV panel during irradiance changes. [ABSTRACT FROM AUTHOR]

RAPID prototyping, PRODUCT design, OPEN innovation, MODULAR design, VIRTUAL communities, and INTERNET of things

An increasingly popular form of open innovation in the digital age is 'making,' where users innovate across multiple disciplines and make products that meet their needs, using mechanical, electronic, and digital components. These users have at their disposal, a wide solution space for innovation through various modular toolkits enabled by digital‐age technologies. This study explores and outlines how these users simplify this wide solution space to innovate and make tangible products. Following a modularity theory perspective, it draws on case studies of users and their innovations: (1) Users with initial prototype product designs based on the Internet of things (IoT) from a maker event and (2) users with established product designs from the online community platform Thingiverse. The studies found that users reused the design in the form of existing off‐the‐shelf products and utilized digital fabrication and low‐cost electronics hardware as a 'glue' to create physical and informational interfaces wherever needed, enabling bottom‐up modularity. They iteratively refined their innovations, gradually replacing re‐used designs with own integrated designs, reducing modularity, and reducing wastage. The study contributes to open innovation and modularity with implications on the design of products and toolkits enabled by the digital age. [ABSTRACT FROM AUTHOR]

RAPID prototyping, SOFTWARE frameworks, ARTIFICIAL neural networks, CONVOLUTIONAL neural networks, NETWORK performance, and COMPUTATIONAL complexity

The huge model size and high computational complexity make emerging convolutional neural network (CNN) models unsuitable to deploy on current embedded or edge computing devices. Recently the binary neural network (BNN) is explored to help reduce network model size and avoid complex multiplication. In this paper, a binary network acceleration framework for rapid system prototyping is proposed to promote the deployment of CNNs on embedded devices. Firstly trainable scaling factors are adopted in binary network training to improve network accuracy performance. The hardware/software co-design framework supports various compact network structures such as residual block, 1 × 1 squeeze convolution layer, and depthwise separable convolution. With flexible network binarization and efficient hardware architecture optimization, the acceleration system is able to achieve over 2 TOPS throughput performance comparable to modern desktop GPU with much higher power efficiency. [ABSTRACT FROM AUTHOR]

RAPID prototyping, SEARCH algorithms, DIELECTRIC-loaded antennas, THREE-dimensional printing, and PERMITTIVITY

A prototyping method for dielectrically loaded antennas is presented. Dielectric loading has been used with horn antennas, feeds, and lenses. Dielectrics have also been used for coating antennas submerged in water and biological matter and have led to improvements in bandwidth and efficiency as well as antenna miniaturisation. The authors present a new technique to produce variable dielectrics with permittivity from 6 to 28 using two commonly available powders, titanium dioxide (used in foods) and magnesium silicate (used in talcum powder). An example spherical helical ball antenna is used to demonstrate the process. In this antenna, the mixed powders were encased in a 3D printed shell that achieved a reduction in diameter of the spherical antenna by a factor of 1.85. The technique aids rapid prototyping and optimisation using search algorithms. [ABSTRACT FROM AUTHOR]

RAPID prototyping, ELECTRIC vehicles, SIGNAL processing, ARTIFICIAL satellite tracking, BRAKE systems, REGENERATIVE braking, and DESIGN

The electro-mechanical brake booster (EMBB) is a kind of mechatronic actuator, which is developed to suit the brake assist requirement of electric vehicles. In this paper, we report on the design of an EMBB system consisting of a dc motor, a two-state reduction of a gear and ball screw, a servo body, and a reaction disk. Considering the inconvenience of installation and high price of the pedal force sensor, we translate the control problem of brake power assist control to position tracking control. Meanwhile, a nonlinear control method for position tracking is presented to solve the problem of power assist braking, which is formalized as three parts: the steady-state control, feed-forward control based on reference dynamics, and state-dependent feedback control. The benefit of the nonlinear control method is that it offers a concise control law and performs well in engineering implementations. In addition, a second-order filter was designed to do the signal processing and obtain a higher-order derivative. Finally, the bench tests based on rapid control prototyping environment were designed and implemented to verify the performance of the controller. Test results show that both the position tracking performance and response time of the EMBB system performed well. [ABSTRACT FROM AUTHOR]

INFORMATION resources management, RAPID prototyping, INDUSTRIAL surveys, COMPUTER software developers, SYSTEMS design, and ORGANIZATION

Many proposed contingencies regarding the conditions when the use of prototyping will lead to successful system development appear in the literature. Using an industry survey, this exploratory study empirically investigates the effect of certain contingencies on system success. Overall, results indicate that five variables, when combined with prototyping, affect system success (as indicated by user satisfaction): innovativeness of the project, impact of the system on the organization, user participation, number of users, and developer experience with prototyping. These results provide some insight into the proper uses of prototyping to improve system success. The results also indicate that several of the current contingencies, if followed, do not ensure high levels of system success. [ABSTRACT FROM AUTHOR]

DEALERS (Retail trade), PURCHASING agents, AFFECT (Psychology), YEAR, and SUSPICION

This paper contributes to our understanding of xinren within buyer-seller relationships. Xinren is often translated to trust and is critical for the development of strong business relationships. Previous conceptualizations and measurements of xinren have been inconsistent and questionable. Through a novel methodology, prototyping analysis, this research outlines a foundational structure for xinren. A series of 4 studies were conducted on xinren in buyer-seller relationships in China involving a total of 311 participants who were employed in sourcing and procurement (33.23%) or marketing and sales (31.29%), and had spent less than one year working outside China. Central prototypical features include high arousal emotions highlighting the importance of affect-based aspects when developing xinren. Negative features indicate that both trust and distrust may be synergistically operating within xinren. Contributions are also made by outlining both universal trust features and more culturally-nuanced trust features. Suggestions for managers indicate how both Eastern and Western partners may use these results to build deeper trust within their relationships. Future research includes undertaking further prototyping analysis on trust within other cultures to develop foundational structures that may include both universal and culturally-nuanced trust features. • Xinren consists of affective, negative, connections and integrity features • 5 strongest features: Honesty, communication, cooperation, liar and reliability • Affective features are high arousal features: happiness, love, joy • Negative features include liar, betray and cheat • Connection features include friends and families [ABSTRACT FROM AUTHOR]

POWER electronics, ATMOSPHERIC temperature, HEAT transfer coefficient, COMPUTATIONAL fluid dynamics, VIRTUAL prototypes, and HEAT transfer

To develop a thermal model for air-cooled plate–fin heatsink and evaluate its thermal performance, empirical equations are available to rapidly calculate the pressure drop and heat transfer coefficients for the fins. Besides the heat transfer coefficients, the local air temperature also affects the heat transfer of the fins, which rises along the channel by absorbing the released heat from the fins. In this article, a heatsink model to account for the air temperature rise is proposed, and a thermal circuit model is used to correlate the increased air temperature and the absorbed heat at the fin boundary. With this convective boundary, the temperature distribution for the base plate of the heatsink is calculated by adopting finite-difference method (FDM), which analyzes the conductive heat transfer for the base plate. Both of them have been programed in MATLAB software, and the calculated temperature by the proposed models is compared with the computational fluid dynamics (CFD) simulation. A fan-cooled plate–fin heatsink for a half-bridge power electronics inverter is tested in the laboratory as an example, and the thermal results obtained from the proposed models are within 10% of error with respect to the CFD simulation results and experimental results. The proposed method is also faster than the CFD simulation. The proposed accurate and rapid thermal modeling method will be essential for virtual prototyping and layout/geometry optimization of power electronics systems. [ABSTRACT FROM AUTHOR]

DESIGN

Recently, multi-FPGA platforms have become a popular choice to prototype complex digital systems. This is because of unique advantages such as high frequency and real world testing experience that are offered when compared to other pre-silicon testing techniques. However, one of several challenges faced by multi-FPGA prototyping is the requirement of an efficient back end flow. Partitioning is a key part of the back end flow of multi-FPGA systems and it directly affects the quality of final prototyped design. In this work, we explore two different partitioning approaches: one is multilevel; while the other is hierarchical partitioning approach. For experimentation, we use a suite of fourteen large benchmarks. Experimental results reveal that the multilevel approach gives 12.5% better frequency results for mono-cluster benchmarks while the hierarchical approach gives 13% better results for multi-cluster benchmarks. Furthermore, the hierarchical approach requires, on average, 60% less execution time when compared to the multilevel partitioning approach. [ABSTRACT FROM AUTHOR]