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In this study, cooling methods for a typical spacecraft circuit board assembly are investigated. The power dissipation of the assembly is more than 100 W, and the max heat dissipation of a component is 16 W, making it very difficult to cool the assembly. According to the packaging characteristics and heat dissipation of the components on the circuit board, cooling methods such as potting brackets, cooling springs, and cooling blocks are used, and the effects of various cooling methods are analyzed. Through simulation and experimental research, it is proven that the power components in the printed circuit board assembly meet the requirements of temperature derating, which provides a reference for the thermal design of spacecraft electronic equipment. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Informacije MIDEM: Journal of Microelectronics, Electronic Components & Materials is the property of MIDEM Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• A novel non-contact measurement method of insulation space charge is proposed. • Charge measurement is based on elasto-optical sensing and ellipsometric detection. • Electrical-mechanical-optical polymorphic signal conversion model is constructed. • 15-µm spatial resolution charge measurement is achieved without averaging. To clarify the insulation charge accumulation mechanism under complex PWM (Pulse width modulation) stress condition, a novel insulation space charge non-contact measurement method based on elasto-optical sensing and ellipsometric detection is proposed. Then, polymorphic signal propagation model between electrical pulse, space charge, elastic wave and optical probe signal is constructed. Meanwhile, the charge measurement feasibility is evaluated experimentally by comparing with traditional PEA (Pulsed Electro-Acoustic) charge detection system. It is shown that the charge ellipsometric detection system could achieve the charge measurement without averaging. In addition, the spatial resolution of the ellipsometric detection system could be about 15 µm, which is consistent with the traditional PEA detection system. The related work could provide a reliable technical means to achieve dynamic tracking of insulation charge evolution under complex stress, supporting the optimization design of the power electronic equipment insulation system. [ABSTRACT FROM AUTHOR]

In this paper, an improved voltage-mode constant on-time (COT) control DC–DC buck converter is designed, which makes the DC–DC buck converter have good stability. Firstly, an improved compensation scheme is introduced through the analysis and derivation of the traditional voltage-mode COT controlled buck converter model. Then, according to the application requirements of the design, Simplis software modeling is used to verify the correctness of the theoretical analysis. The 0.13 μ m BCD technology is used to tape out the DC–DC converter of the improved voltage mode COT. The input voltage is 3.7–5.5 V and the output voltage is 3.3 V. The chip test mainly includes heavy-load condition in CCM operation, light-load condition in DCM operation, and load transient response. The test results show that the chip can remain stable under heavy-load and light-load conditions. The overshoot and undershoot in transient response can be quickly restored to steady state during the recovery process. Finally, compared with chips of the same type, it shows that the DC–DC chip for portable electronic equipment designed in this paper adopts an internal compensation structure, which has good stability, simple design, small main chip area, simple peripheral equipment, and good application value. [ABSTRACT FROM AUTHOR]

As forced-air cooling for heat sinks is widely used in the cooling design of electrical and electronic equipment, their thermal performance is of critical importance for maintaining excellent cooling capacity while reducing the size and weight of the heat sink and the equipment as a whole. This paper presents a method based on the combination of computational fluid dynamics (CFD) simulation and surrogate models to optimize heat sinks for high-end energy storage converters. The design takes the thermal resistance and mass of the heat sink as the optimization goals and looks for the best design for the fin height, thickness and spacing, as well as the base thickness. The analytical and numerical results show that the thermal resistance and mass of the heat sink are reduced by the proposed algorithms, as are the temperatures of the heating elements. Test results verify the effectiveness of the optimization method combining CFD simulation with surrogate models. [ABSTRACT FROM AUTHOR]

Snorkeling equipments have played a vitally important role in various underwater operations, such as military, rescue activities, underwater research, archeology, and so on. However, existing snorkeling styles, represented by mechanical lifting system, artificial diving, and submarine mode (water storage and drainage), still face numerous challenges in the issues of large energy loss, complex structure, or environmental unfriendliness. Especially for small flexible equipments, an efficient and convenient way of snorkeling is of prime importance to various underwater explorations for a long time. Here, for the first time, an automatic snorkeling electronic equipment driven by a self‐breathing flexible aqueous aluminum‐air battery (Self‐BAAAB) which integrates functions of the snorkeling and the electric energy supply is designed. The self‐BAAAB battery consists of naturally inspired spongy sodium polyacrylate (PANa) hydrogel that acts as a flexible electrolyte and vertical N–O doped graphene fiber (NOGF) as an ORR/OER/HER trifunctional electrocatalyst. Benefited from the trifunctional catalytic properties and the aluminum metal stripping, the Self‐BAAAB consumes oxygen gas in the routine discharge process while the gas in turn is released during the charging process due to electrolysis of water in the super‐absorbing hydrogel, which triggers the sharp density variation of Self‐BAAAB, driving the "automatic snorkeling" feature of electronic equipment underwater. This work provides new insights into the design of the snorkeling electronic equipments and would promote the high efficiency of underwater operations, especially in a complex environment. [ABSTRACT FROM AUTHOR]

In this paper, in view of the uncertainty of geometric parameters of braided-shielded cable and structural parameters of the shield in practical problems, polynomial chaos expansions (PCE) is used to explore the uncertainty quantification of a crosstalk calculation model of braided-shielded cable. First, the model based on multi-conductor transmission line theory is expanded by PCE. Second, the truncation degrees of polynomials and sample size of PCE are determined by the leave-one-out method, and the statistical characteristic parameters of crosstalk are obtained by combining coefficients of polynomials. Compared with the calculation results of the Monte Carlo method, the mean value, standard deviation and probability density function obtained by the two methods are basically consistent, but the PCE method has obvious advantages in calculation efficiency. Finally, the influence of input variable parameters in the crosstalk calculation model of braided-shielded cable are calculated by combining the PCE and the Sobol's global sensitivity analysis method, which provides theoretical guidance for the electromagnetic compatibility design of electrical and electronic equipment using braided-shielded cable. [ABSTRACT FROM AUTHOR]

This article shows how new forms of electronic products and services become economically feasible and thus candidates for commercialization and creative destruction as improvements in standard electronic components such as microprocessors, memory, and displays occur. Unlike the predominant viewpoint in which commercialization is reached, as advances in science facilitate design changes that enable improvements in performance and cost, most new forms of electronic products and services are not invented in a scientific sense, and the cost and performance of them are primarily driven by improvements in standard components. They become candidates for commercialization, as the cost and performance of standard components reach the levels necessary for the final products and services to have the required levels of performance and cost. This suggests that when managers, policy makers, engineers, and entrepreneurs consider the choice and timing of commercializing new electronic products and services, they should understand the composition of new technologies, the impact of components on a technology's cost, performance and design, and the rates of improvement in the components. [ABSTRACT FROM AUTHOR]

In order to ensure the normal operation of software electronic equipment and better guide the electromagnetic protection design of software electronic equipment, a set of computational models and numerical methods are needed to analyze the electromagnetic interference problems of electronic equipment. To this end, a new field-path hybrid time domain algorithm is adopted to simulate the electromagnetic interference of broadband electromagnetic signals to software electronic equipment in the time domain; the results are compared with those of the FDTD method to verify the correctness and efficiency of the algorithm. The average calculation time of FDTD is 478.3 min, while that of the field-path hybrid time domain algorithm is 46.5 min. The results show that the simulation effect of the field-path hybrid time domain algorithm is consistent with that of FDTD and saves a lot of memory and computation time, which proves the correctness and efficiency of the algorithm. [ABSTRACT FROM AUTHOR]

An open hardware design and implementation for a transient absorption spectrometer are presented that has microsecond time resolution and measures full difference spectra in the visible spectral region from 380 to 750 nm. The instrument has been designed to allow transient absorption spectroscopy measurements of either low or high quantum yield processes by combining intense sub-microsecond excitation flashes using a xenon lamp together with stroboscopic non-actinic white light probing using LED sources driven under high pulsed current from a capacitor bank. The instrument is sensitive to resolve 0.15 mOD flash-induced differences within 1000 measurements at 20 Hz repetition rate using an inexpensive CCD sensor with 200 μm pixel dimension, 40 K electrons full well capacity and a dynamic range of 1800. The excitation flash has 230 ns pulse duration and the 2 mJ flash energy allows spectral filtering while retaining high power density with focussing to generate mOD signals in the 10–4–10–1 ΔOD range. We present the full electronics design and construction of the flash and probe sources, the optics as well as the timing electronics and CCD spectrometer operation and modification for internal signal referencing. The performance characterisation and example measurements are demonstrated using microsecond TAS of Congo red dye, as an example of a low quantum yield photoreaction at 2% with up to 78% of molecules excited. The instrument is fully open hardware and combines inexpensive selection of commercial components, optics and electronics and allows linear response measurements of photoinduced reactions for the purpose of accurate global analysis of chemical dynamics. [ABSTRACT FROM AUTHOR]

A radar system requires a number of high-power components operating in a narrow and convection-free environment. This study aims to develop an integrated heat dissipation system that is suitable for the high-power electronic equipment of radar systems. The proposed heat dissipation mechanism integrates a fluid circulation-type cold plate with a quad transmit receive module. The finite element method in the COMSOL fluid–solid coupling heat transfer analysis software was used to analyze the heat dissipation performance of the cold plate in the proposed mechanism. The Taguchi method was adopted to optimize the cold plate design. The simulation and experimental results show that the proposed mechanism can control the temperature equalization and temperature of the system within the specified requirements. The practicality of the proposed mechanism was verified. The findings can serve as a reference for the design of high-power electronic equipment in a heat dissipation system. [ABSTRACT FROM AUTHOR]

Offset printing processes are promising candidates for producing printed electronics due to their capacity for fine patterning and suitability for mass production. To print high-resolution patterns with good overlay using offset printing, the velocities of two contact surfaces, which ink is transferred between, should be synchronized perfectly. However, an exact velocity of the contact surfaces is unknown due to several imperfections, including tolerances, blanket swelling, and velocity ripple, which prevents the system from being operated in the synchronized condition. In this paper, a novel method of measurement based on the sticking model of friction force was proposed to determine the best synchronized condition, i.e., the condition in which the rate of synchronization error is minimized. It was verified by experiment that the friction force can accurately represent the rate of synchronization error. Based on the measurement results of the synchronization error, the allowable margin of synchronization error when printing high-resolution patterns was investigated experimentally using reverse offset printing. There is a region where the patterning performance is unchanged even though the synchronization error is varied, and this may be viewed as indirect evidence that printability performance is secured when there is no slip at the contact interface. To understand what happens at the contact surfaces during ink transfer, the deformation model of the blanket's surface was developed. The model estimates how much deformation on the blanket's surface can be borne by the synchronization error when there is no slip at the contact interface. In addition, the model shows that the synchronization error results in scale variation in the machine direction (MD), which means that the printing registration in the MD can be adjusted actively by controlling the synchronization if there is a sufficient margin of synchronization error to guarantee printability. The effect of synchronization on the printing registration was verified experimentally using gravure offset printing. The variations in synchronization result in the differences in the MD scale, and the measured MD scale matches exactly with the modeled MD scale. [ABSTRACT FROM AUTHOR]

Electrical discharge and electrostatics are used for the industrial application of a copying machine and electrostatic spraying. However, the electrical discharge and electrostatics occasionally cause malfunction or failure of electronic equipment. When a human body moves in an office, it is electrified up to 10 kV or more. A microelectronic device used in the electronic equipment causes an error owing to the voltage of less than 10 V. When the charged human body moves near the electronic equipment, high induced voltage is generated in the metal box. Comprising electronic equipment, the box is occasionally used at the floating potential of an ungrounded condition. The induced voltage generated for the ungrounded metal box is higher than that generated for the grounded metal box. The results show that the induced voltage generated in an ungrounded metal box is 120% of the inverse polarity against a charged body when the charged body moves away from the box. The induced voltage generated in the ungrounded metal box is higher than that generated on the box. These results would be helpful in designing electronic equipment without malfunctions or failure. [ABSTRACT FROM AUTHOR]

In electronic equipment, thermal failure and thermal degradation are two increasingly prominent problems of the devices, with the deepening integration and growing power density. Currently, there are relatively few reports on the heat transfer mechanism, heat source analysis, and numerical simulation of electronic equipment containing power electronic devices (PEDs). Therefore, this paper carries out thermal design and evaluates the cooling performance of PED-containing electronic equipment. Firstly, the basic flow was given for the thermal design of PED-containing electronic equipment; the heat transfer mode of PEDs and the equipment were detailed, so was the principle of thermal design; the cooling principles were introduced for ventilation cooling, heat pipe cooling, and closed loop cooling. Then, numerical simulation was carried out on the solid and liquid state heat transfer of PEDs and the equipment under different cooling modes. Based on an engineering example, the cooling scheme was finalized through heat source analysis on the proposed electronic equipment. The experimental results rove the effectiveness of numerical simulation and electronic equipment cooling scheme. The results provide a reference for the cooling scheme design for other fields of thermal design. [ABSTRACT FROM AUTHOR]

One of the most challenging tasks of companies with complex and discrete production systems is to determine an appropriate production control strategy (PCS). The PCS is crucial, as it influences inventory, costs, and service. We propose a framework to address the most important questions of PCS engineering: limiting work in process, positioning the order penetration point (OPP), and coping with demand uncertainty upstream the OPP. Thereby, uncertain advance demand information in the form of forecasts is considered and desirable characteristics of push and pull strategies are combined. A serial manufacturing system with multiple products, variable processing times, and uncertain advance demand information is examined. The model is formulated as a queuing network model and solved numerically by discrete-event simulation. The framework and a resulting hybrid control strategy are applied to a case study from electronics manufacturing, where a significant improvement potential is identified. [ABSTRACT FROM PUBLISHER]

Technological innovation and satisfaction of customer needs are the keys to survival and success for firms, especially in global competitive high-tech industries. Since new products are usually a source of new sales and profits, the success of new product development (NPD) is essential to maintain a competitive edge and to make a decent profit in a longer term. Therefore, how to develop products that deliver the quality and functionality customers demand while generating the desired profits becomes an important task for the manufacturers. In this paper, a framework with two phases is constructed for facilitating the selection of engineering characteristics (ECs) for product design. In the first phase, quality function deployment (QFD) is incorporated with the supermatrix approach of analytic network process (ANP) and the fuzzy set theory to calculate the priorities of ECs with the consideration of the interrelationship among factors and the impreciseness and vagueness in human judgments and information. In the second phase, multi-choice goal programming model is constructed by considering the outcome from the first phase and other additional goals, such as NPD cost and manufacturability, in the attempt to select the most suitable ECs. A case study of the product design process of backlight unit (BLU) in thin film transistor liquid crystal display (TFT-LCD) industry in Taiwan is carried out to verify the practicality of the proposed framework. [ABSTRACT FROM AUTHOR]

We have investigated the effect of cell resolution change on the luminous efficacy of an alternating current plasma display panel with the three-dimensional plasma simulation. The luminous efficacy decreased and the minimum sustain voltage increased as the resolution increased from VGA to full high definition (HD) resolution, due to the increased particle loss to the enclosing surfaces. A simple increase of the Xe content to realize the high luminous efficacy resulted in a much enhanced luminous efficacy decremental ratio as the cell resolution increases because of the increased plasma loss and decreased electron heating efficacy. We are proposing some effective ways of realizing high luminous efficacy in the high resolution 50-in. full HD cell, such as the increase of the sustain electrode gap, the adoption of a segmented electrode in delta color arrayed, enclosed subpixel, type cell with 4:3 aspect ratio, and the optimization of the barrier rib height. Because the adoption of those geometrical parameters causes the reduced plasma loss, the transport efficacy of visible light from phosphor through the front plate in a full HD cell resulted in much increased improvement with the increase of Xe content. [ABSTRACT FROM AUTHOR]

There are many cases, especially in the electronics industry, of manufacturing activities involving very high volumes of components that, whilst individually costing very little, can cause very expensive failures or recalls upon unexpected failure. The identification of such outliers in component supply is therefore of great interest. These items are often within design technical specification but their deviation from the characteristics of the rest of the population may be indicative of some underlying cause that can lead to their premature failure in service. Identification of outliers using conventional statistical process control (SPC) and Control Charting techniques is often uncertain and most other published methods are inappropriate for dynamic monitoring. This paper proposes a simple and practical technique that has proved successful in identifying such components whilst minimizing ‘false alarms’. In many cases these items have subsequently been found to pass short-term inspection tests but fail well short of their design life. [ABSTRACT FROM AUTHOR]

Here, the setup of a three-phase 100 A linear amplifier is proposed. This work focusses on the use of this linear amplifier as power element for machine-emulation. In contrast to common power electronics, a linear amplifier avoids ripple content in the output current caused by switched-mode operation. [ABSTRACT FROM AUTHOR]

Feature-based design is an approach that promises substantial benefits in capturing and transferring a designer's intent to other stages of design and manufacturing, thereby helping to integrate the diverse functions associated with design and manufacturing. While feature-based design has considerable potential, it has been applied almost entirely to mechanical design. Furthermore feature-based design has been implemented in a relatively ad hoc manner and, consequently, much of the work on feature-based design cannot be readily applied to other domains. This paper aims to address some of this deficiency by describing a feature-based design system for electronic manufacture that is based on the firm formalism of a feature algebra and a feature-based design algorithm. An electronics assembly feature taxonomy is developed, together with feature operators and validation scheme. These are used to build a prototype feature-based design system called Feature-Based Design of Electronics Assemblies (FEBEA). The format of this paper is as follows. The representation formalism is briefly described. The electronics assemblies design demon is then detailed. The design domain is formally defined and an electronics assemblies design module is constructed. A testability evaluation module is then developed. Finally the prototype implementation of FEBEA is described, and how design is represented and performed using FEBEA is illustrated through an example design scenario. The contribution of this paper is, first, to place the feature-based design of electronics assemblies on a finn formalism foundation. Second, to develop a feature taxonomy for electronics assembly design. Third, to define feature operators and feature validity for electronics assemblies. Fourth, to develop a feature transformation scheme for testability evaluation. Finally, to show how such a feature-based approach can be implemented. The overall result is an approach that allows the designer to design an... [ABSTRACT FROM AUTHOR]

This paper deals with the problem of determining an optimum unit load size of automated guided vehicle (AGV) in an electronics assembly production line. It is assumed that an AGV delivers assembly parts to each workstation from a miniload automated storage/retrieval system and a conveyor line transports subassemblies between workstations. Two types of operating policies for the AGV system are proposed. For each policy, a nonlinear mathematical model is formulated. Based on the characteristics of the objective function and feasible region, a solution algorithm is developed, which finds an optimum unit load size. To illustrate the models, problems are chosen and solved. [ABSTRACT FROM AUTHOR]

This paper proposes a two-stage practical product batching and batch sequencing algorithm for NC punch presses used in the production of precision sheet metal electronics components. The first stage of the algorithm batches a given set of products in order to maximize the number of products in a batch as well as the tool magazine utilization. In this stage, tool magazine constraints such as number of available slots, size of slots, tool configurations and tool locations are taken into consideration. The resulting batches are passed to the second stage of the algorithm which sequences these batches. The sequencing is done by using the 'nearest neighbour' heuristic for the 'travelling salesman problem'. Comparison of the new method with the procedure previously used by a manufacturer of such components demonstrated a significant reduction in setup times. [ABSTRACT FROM AUTHOR]

Presents the EDS society upcoming meetings and events. [ABSTRACT FROM AUTHOR]

Permanent magnets, especially Nd-Fe-B magnets are very important engineering elements that are widely used in many applications. Detailed design of electrical and electronic equipment using permanent magnets requires precise measurement of magnetic characteristics. We developed a measurement system which can measure the magnetic characteristics of permanent magnets precisely. This paper presents the measured results of magnetic characteristics of various types of permanent magnets and comparison of these characteristics. [ABSTRACT FROM AUTHOR]

Heat sinks (HSs) are designed for the mechanical, electrical and electronic components that generate heat in considerable amount. For this purpose, an aluminum conical pin fin heat sink is designed. Aluminum conical pin-fins geometry has been experimentally investigated for the blowing direction (pushing or pulling) which is the energy efficient option for the heat sink. The heat sink was tested at the same fan power for pushing and pulling conditions for 25, 50, 75 and 100 W resistance heater power. Designed aluminum conical pin fin heat sink can be easily used in heat sweeping processes. It has found that pushing configuration of the fan is more efficient for this design. [ABSTRACT FROM AUTHOR]

An immersive sound system has been created that allows for the real time control over sound source localization. It is a multi-user client/server system where the client devices are mobile devices, thereby allowing remote control over sound source localization. Touch and orientation capabilities of mobile devices are used for the generation of three-dimensional coordinates. The server receives localization control messages from the client and uses an Ethernet AVB network to distribute appropriate mix levels to speakers with in-built signal processing. These localization messages can be recorded by users for later playback. [ABSTRACT FROM AUTHOR]

This work describes the use of a benchtop razor printer to fabricate epidermal paper-based electronic devices (EPEDs). This fabrication technique is simple, low-cost, and compatible with scalable manufacturing processes. EPEDs are fabricated using paper substrates rendered omniphobic by their cost-effective silanization with fluoroalkyl trichlorosilanes, making them inexpensive, water-resistant, and mechanically compliant with human skin. The highly conductive inks or thin films attached to one of the sides of the omniphobic paper makes EPEDs compatible with wearable applications involving wireless power transfer. The omniphobic cellulose fibers of the EPED provide a moisture-independent mechanical reinforcement to the conductive layer. EPEDs accurately monitor physiological signals such as ECG (electrocardiogram), EMG (electromyogram), and EOG (electro-oculogram) even in high moisture environments. Additionally, EPEDs can be used for the fast mapping of temperature over the skin and to apply localized thermotherapy. Our results demonstrate the merits of EPEDs as a low-cost platform for personalized medicine applications. [ABSTRACT FROM AUTHOR]

Mode conversion in differential lines paired with serpentine in PCB layouts of mobile electronic devices is investigated. Different shapes and dimensions are analyzed and design of experiments based on Response Surface Model is used to study the sensitivity of various design parameters to both signal integrity and electromagnetic interference. It is found that mode conversion is negatively affected by the numbers of meanders, the length of bends and their angle. Design guidelines are provided and an alternative shape named trombone is proposed as possible solution to minimize the mode conversion while maximizing the skew matching and reducing the routing area. More than 10 dB of reduction in common mode noise is achieved in a broadband frequency range 0–10 GHz for most of the cases studied. [ABSTRACT FROM PUBLISHER]

Ray Mears has developed a portable sound system that he thinks will be able to offer him an additional income. As a music minister at a small local church he has been searching for something to supplement his salary so that he can continue to afford to do what he loves (church music). With his knowledge of church and overseas missions ' audio system needs, he developed a sound system that is very versatile and affordable for such customers. He has established a company, Mears Power-T, Inc., to begin to manufacture and market his design if it appears feasible. [ABSTRACT FROM AUTHOR]