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In this paper, we first give some historical background and trends in PV module technologies with a focus on the growing trend towards 'PV everywhere', mainly targeting improved aesthetics, dimensional freedom including curved surfaces, weight concerns and specific reliability testing. This section acts as an introductory review of the field. Then, in the following sections, we elaborate on two technological developments in this field where we are active: (i) multi‐wire interconnection and (ii) advanced encapsulation. In terms of multi‐wire interconnection, this technology offers improved aesthetics, a similar performance and dimensional freedom compared to the traditional tabbing‐stringing process, and the experiments show promising results on extended reliability testing, including thermal cycling, damp heat and humidity freeze, as well as high‐temperature storage. In terms of advanced encapsulation, we introduce our approach for curved surfaces using a double‐membrane laminator and present results on fabricating curved modules, targeting as demonstration examples on the one hand, glass–glass sunroofs, and on the other hand, lighter‐weight bonnets for automotive applications. We mix examples targeting building and automotive applications, to illustrate the variety of requirements (colours, curvature, weight, reliability, safety), although this variety within building and vehicle applications is probably as large as between them. [ABSTRACT FROM AUTHOR]

There is a growing interest in the development of microelectronics that can perform reliably and robustly at temperatures above 300 °C. Such devices require stable thermal properties, low thermal drift, and thermal cycling resistance. Conventional hybrid circuit technology demonstrates high‐temperature packages, but the high costs and lead time are significant drawbacks. In contrast, additive manufacturing processes, including aerosol jet printing (AJP), offer cost and time benefits, as well as 3D structures and embedded features. However, the properties and reliability of additive packaging materials at extreme temperatures are not well known. Herein, the reliability at temperatures up to 750 °C in terms of electrical performance and mechanical strength of aerosol jet printed gold thick films onto ceramic substrates are assessed. Thermal coefficient of resistance of printed gold films is measured. The electrical resistance stability and leakage current of printed gold structures are also characterized during over 100 h of aging at temperatures up to 750 °C. Finally, the mechanical adhesion strength of the printed gold films is evaluated after aging for 100 h at temperatures up to 750 °C. The adhesion of the printed gold to the ceramic substrates remains high after aging, very stable resistances and minimal leakage currents have been observed. [ABSTRACT FROM AUTHOR]

It is significant to promote reliability testing and assessment research of hydraulic cylinder which is the basis to improve reliability of the cylinder and pertinent machine system. In this study, a new comprehensive testing system for the reliability research of hydraulic cylinder has been developed, reliability testing of a hydraulic cylinder for precision production has been conducted using the test bench. With the obtained test data, parameters of the Weibull distribution function of the cylinder are estimated by means of the least square estimation method, thus, reliability distribution function and lifetime values of the cylinder under normal stress level are ultimately obtained. The developed new test bench and performed testing and analysis in this study would provide an excellent platform and reliability assessment approach for industry hydraulic cylinders. [ABSTRACT FROM AUTHOR]

Although ethylene vinyl acetate copolymer (EVA) is still the dominant PV encapsulant, polyolefins (PO) have gained market share in recent years. Like EVA, PO can be mixed with a cross-linking agent and chemically reacted during the lamination process to form polyolefin elastomers (POE). The cross-linked and therefore insoluble fraction of the encapsulation can be determined by extracting the soluble part of the material with a solvent. The degree of cross-linking, or gel content (GC), is determined from the mass ratio before and after extraction of the samples. The analytical methods for determining the GC value are described for example in IEC 62788-1-6 and the Chinese national standard GB/T29848-2018. We observe a significant difference between the test results of these two standards, with the GC values resulting from the GB standard test being significantly higher. This is particularly true in the low GC range. The main reason for this difference is the extraction time of 5 h specified in the GB standard, which is insufficient to ensure complete extraction of the non-crosslinked polymers at lower GC values. However, for certain POE materials the required minimum GC (50%-65%) is exactly in this range.

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• The reliability of high-power switches in Fast Discharge Unit (FDU) is very important for the safety operation of superconducting magnets. In this paper, the reliability and test number of FDU switches are discussed. • The FDU configuration characteristics of different types of superconducting magnets are introduced, and some explanation and calculation on reliability are provided. • The reliability interval estimation after a certain test number is discussed by using the binomial distribution theory. • The reliability conformance test based on the claimed reliability is discussed to derive the test number. High-power switches, as the important active part of Fast Discharge Unit (FDU) in Tokamak, are designed to interrupt the circuit current and transfer the quench energy for protecting expensive superconducting magnets. Hence, their reliability has always been highly underlined. In this paper, the reliability and test number of FDU switches are discussed, mainly including three issues. First, the FDU configuration characteristics of different types of superconducting magnets are introduced, and explanations and calculations on reliability are provided. Second, the reliability interval estimation after a certain test number is discussed by using the binomial distribution theory. Three, the compliance test based on the claimed reliability is studied, and two types of test plans are discussed and compared to derive the test number. The discussion in this paper focuses on the FDU switches and provides valuable guidance for their reliability test and assessment. [ABSTRACT FROM AUTHOR]

Advanced indentation techniques have been introduced to study the effects of multiple stresses on the transistor characteristics with using a cylindrical tip with various alignments. Particularly, controlling the cylinder tip orientation relative to the transistor channel direction is proposed to selectively strain the silicon channels in order to induce very different selectively controlled stresses. Several tip alignments allow to shift the stresses from uniaxial towards biaxial stress as well as to induce shear stress. Ring oscillator circuits based on NAND and NOR gates are used to monitor the stress effects on the characteristic circuit frequency as well as on the individual transistors. Finite Element simulations help to identify optimized setup properties for the targeted application. Comparison with previous indentation experiments derives the specific influence of each stress tensor component on the transistor characteristics. [ABSTRACT FROM AUTHOR]

In this paper, truncated lifetime testing is considered, and new single acceptance sampling plans (SASP) are proposed assuming that the lifetime distribution is the q-Weibull distribution of a product. Assuming a finite population size (limited population size, N); the inspection process for a single sampling plan is ASP(n,p) begins by choosing a simple random sample from a given lot, then based on pre-assigned quality standards, the manager will decide to reject the lot if some items fail to meet the pre-assigned quality standards. Since the population is limited; then this experiment meets the hypergeometric distribution assumptions. The hypergeometric theory is applied to compute the probability of acceptance, and the procedure is used to compute the minimum sample size and the operating characteristics of the sampling plans. Also, a real data analysis is given to illustrate the applicability of the proposed plan in the industry. [ABSTRACT FROM AUTHOR]

Minimum-cost reliability test durations based on gamma failure count data are found by solving mixed integer nonlinear programming problems. The optimal numbers of test units and failures allowed are also determined. A linear combination of test time and sample size is minimized assuming that producer and consumer risks are controlled. A quite accurate approximation of the smallest feasible acceptance number is deduced in closed-form. Moreover, a fast and efficient iterative algorithm is presented in order to obtain the optimal reliability demonstration test plan, which provides the best criterion to decide the acceptability of submitted lots and production processes. Furthermore, some descriptive analyses of the proposed inspection schemes, as well as applications of the developed methodology to the manufacturing of deep groove ball bearings, semiconductor lasers, and water pumps, are provided for illustrative and comparative purposes. [ABSTRACT FROM AUTHOR]

Summary: Embedded systems have high coupling and dependency among different hardware and software components in heterogeneous layers, which makes location and issue tracking in their testing difficult. Despite these poor verification conditions, even the most important reliability quality verification among embedded system characteristics is verified with insufficient sample size, typical test cases, and general test strategies, following limitations such as development costs and scheduling. As a result, shipments are highly likely to lead to various reliability quality problems because items have not been verified considering reliability quality characteristics. Hence, to address this gap, this study developed remote embedded device test framework on the cloud (RED‐TFC), which has an innovative reliability test manager component that can automatically perform various tests for the evaluation of reliability and performance of distributed shared devices by utilizing the cloud concept. RED‐TFC offers two key enhancements over existing testing services: (i) the adaptive sample scale for reliability test (ASRT), a feature that identifies the most appropriate sample size for performing functionality and reliability tests of remote verification targets connected to the RED‐TFC server; and (ii) the mass sample reliability test (MSRT), which uses a test case that is specific to reliability, with the sample size obtained by ASRT, to perform verification following the Markov prediction process. This paper analyses two Android smartphone models considered the most generic examples, including many embedded components, and presents a method of detecting a high number of reliability problems in smartphones using the proposed RED‐TFC and its implications. [ABSTRACT FROM AUTHOR]

The study tested the validity and reliability of the "Disaster Response Self-Efficacy Scale" Arabic version (DRSES-A) among Saudi nursing students. Disaster self-efficacy is one such factor of increasing interest. Little research has explored disaster response self-efficacy despite growing evidence on disaster response preparedness in Saudi Arabia. A systematic, standardized and valid instrument is needed to assess disaster self-efficacy in the Saudi context. The DRSES is one of the tools with excellent psychometric properties that can evaluate the nursing students' perceived self-efficacy in disaster preparation, mitigation and response. This investigation is a quantitative methodological design testing the validity and reliability of the DRSES-A. In this study, 290 Saudi nursing students were surveyed from May to June 2021 in the three government universities in Saudi Arabia using the convenience sampling technique. The Disaster Response Self-Efficacy Scale underwent a linguistic adaptation following a forward-backward translation method. Construct validity was established using the principal component analysis to extract the components of DRSES-A. The overall mean of the DRSES-A was 3.41 (SD = 0.75). The overall Cronbach alpha was 0.939. The subscales "Onsite rescue" and "Psychological nursing" had a similar alpha of 0.911, while "Role quality and adaptation" had a computed alpha of 0.878. The expert rated all item content validity index as 1 with an average score content validity index of 1. The principal component analysis supported a three-factor DRSES-A. The DRSES-A is a valid and reliable scale that can measure Arabic-speaking baccalaureate nursing students' self-reported disaster response self-efficacy. [ABSTRACT FROM AUTHOR]

We report on the modification of tin (Sn) film surfaces under a laser beam irradiation that triggers surface plasmon polariton (SPP) excitations. The observed surface features in the form of small raised grains, with well-defined rooting, look similar to tin whisker nodules. We attribute the appearance of those features to the field-induced nucleation caused by the SPP related strong electric field. Possible implications of our findings include accelerated-life testing for tin whisker growth related reliability as well as applications to nanoparticle nucleation. [Display omitted] [ABSTRACT FROM AUTHOR]

The current design paradigm of car cabin components assumes seats aligned with the driving direction. All passengers are aligned with the driver that, until recently, was the only element in charge of controlling the vehicle. The new paradigm of self-driving cars eliminates several of those requirements, releasing the driver from control duties and creating new opportunities for entertaining the passengers during the trip. This creates the need for controlling functionalities that must be closer to each user, namely on the seat. This work proposes the use of low-cost capacitive touch sensors for controlling car functions, multimedia controls, seat orientation, door windows, and others. In the current work, we have reached a proof of concept that is functional, as shown for several cabin functionalities. The proposed concept can be adopted by current car manufacturers without changing the automobile construction pipeline. It is flexible and can adopt a variety of new functionalities, mostly software-based, added by the manufacturer, or customized by the end-user. Moreover, the newly proposed technology uses a smaller number of plastic parts for producing the component, which implies savings in terms of production cost and energy, while increasing the life cycle of the component. [ABSTRACT FROM AUTHOR]

The recent tremendous advances in medical technology at the level of academic research have set high expectations for the clinical outcomes they promise to deliver. To the demise of patient hopes, however, the more disruptive and invasive a new technology is, the bigger the gap is separating the conceptualization of a medical device and its adoption into healthcare systems. When technology breakthroughs are reported in the biomedical scientific literature, news focus typically lies on medical implications rather than engineering progress, as the former are of higher appeal to a general readership. While successful therapy and diagnostics are indeed the ultimate goals, it is of equal importance to expose the engineering thinking needed to achieve such results and, critically, identify the challenges that still lie ahead. Here, we would like to provoke thoughts on the following questions, with particular focus on microfabricated medical devices: should research advancing the maturity and reliability of medical technology benefit from higher accessibility and visibility? How can the scientific community encourage and reward academic work on the overshadowed engineering aspects that will facilitate the evolution of laboratory samples into clinical devices? [ABSTRACT FROM AUTHOR]

The mechanical properties of an ankle-foot orthosis (AFO) can impact how a user's movement is either restricted or augmented by the device. However, standardized methods for assessing stiffness properties of AFOs are lacking, posing a challenge for comparing between devices and across vendors. Therefore, the purpose of this study was to quantify the rotational stiffness of thirteen commercial, nonarticulated, carbon composite ankle-foot orthoses. A custom, instrumented test fixture, for evaluating mechanical properties in rotating exoskeletons (EMPIRE), deflected an AFO through 20 deg of plantar/dorsiflexion motion about a specified, but adjustable, ankle axis. Sagittal, frontal, and transverse plane rotational stiffness were calculated, and reliability was assessed between cycles, sessions, and testers. The EMPIRE demonstrated good-to-excellent reliability between testers, sessions, and cycles (intraclass correlation coefficients all ≥0.95 for sagittal plane stiffness measures). Sagittal plane AFO stiffness ranged from 0.58 N·m/deg to 3.66 N·m/deg. AFOs with a lateral strut demonstrated frontal plane stiffnesses up to 0.71 N·m/deg of eversion while those with a medial strut demonstrated frontal plane stiffnesses up to 0.53 N·m/deg of inversion. Transverse plane stiffnesses were less than 0.30 N·m/deg of internal or external rotation. These results directly compare AFOs of different models and from different manufacturers using consistent methodology and are intended as a resource for clinicians in identifying a device with stiffness properties for individual patients., (Copyright © 2022 by ASME.)