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- 实验方案
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[IEEE 2018 11th UK-Europe-China Workshop on Millimeter Waves and Terahertz Technologies (UCMMT) - HangZhou, China (2018.9.5-2018.9.7)] 2018 11th UK-Europe-China Workshop on Millimeter Waves and Terahertz Technologies (UCMMT) - High-Efficiency Transmission-Type Digital Coding Metasurface for Metalens and Transmitarray
摘要： Field-programmable gate arrays (FPGAs) have been shown to provide high computational density and efficiency for many computing applications by allowing circuits to be customized to any application of interest. FPGAs also support programmability by allowing the circuit to be changed at a later time through reconfiguration. There is great interest in exploiting these benefits in space and other radiation environments. FPGAs, however, are very sensitive to radiation and great care must be taken to properly address the effects of radiation in FPGA-based systems. This paper will highlight the effects of radiation on FPGA-based systems and summarize the challenges in deploying FPGAs in such environments. Several well-known mitigation methods will be described and the unique ability of FPGAs to customize the system for improved reliability will be discussed. Finally, two case studies summarizing successful deployment of FPGAs in radiation environments will be presented.
关键词： radiation effects,radiation hardening,field programmable gate arrays,integrated circuit reliability,Fault-tolerant systems
更新于2025-09-23 15:19:57
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Degradation in photovoltaic encapsulation strength of attachment: Results of the first PVQAT TG5 artificial weathering study
摘要： Delamination of the encapsulant in photovoltaic (PV) module technology results in immediate optical loss and may enable subsequent corrosion or mechanical damage. The effects of artificial weathering were not previously known; therefore, an empirical study was performed to survey the factors most affecting adhesion, including the ultraviolet (UV) source (ie, Xe or fluorescent lamp[s]), the optical filters for the lamp, the chamber temperature, and the relative humidity. Natural weathering was also performed at locations, including the following: Golden, Colorado; Miami, Florida; Phoenix, Arizona; QiongHai, China; Riyadh, Saudi Arabia; and Turpan, China. Specimens were constructed using a laminated glass/poly (ethylene-co-vinyl acetate)/glass geometry. The compressive shear test (CST) was used to quantify the mechanical strength of attachment, taken as a proxy for adhesion. The fractography of select specimens (including cross-sectional optical microscopy) was used to verify the failure mode (delamination or decohesion). Additional analysis of the local solar spectrum as well as the specimen temperature was performed to interpret the results of natural weathering. The goals of this study include to identify the most significant stressors, clarify where strong coupling may occur between stressors, and validate accelerated test results relative to natural weathering. The importance of specimen conditioning (for moisture) and hygrometric degradation as well as the effects of UV degradation are identified in this study.
关键词： EVA,durability,reliability,xenon,UVA-340
更新于2025-09-23 15:19:57
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Reliability of laser-assisted hindfoot alignment evaluation
摘要： [Purpose] A goniometer is frequently used for static measurement of hindfoot alignment. However, although goniometer measurements require experience, their reliability and validity remain controversial. We developed a hindfoot alignment measurement method by laser as an alternative measure. The purpose of this study was to examine the reliability of laser-assisted hindfoot alignment evaluation. [Participants and Methods] Two non-expert examiners (without medical knowledge), briefly trained in the use of laser-assisted hindfoot alignment evaluation, evaluated hindfoot alignment in 12 healthy participants. [Results] The ICC of the intra-rater reliability was 0.74 for both examiners and the ICC for inter-rater reliability was 0.43. [Conclusion] The good intra-rater and moderate inter-rater reliability of laser-assisted hindfoot alignment evaluation, when used by non-professionals, suggest the laser-assisted hindfoot alignment evaluation may be appropriate for use in clinical practice settings.
关键词： Reliability,Laser beam,Hindfoot alignment
更新于2025-09-23 15:19:57
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High-Performance Megahertz-Frequency Resonant DC-DC Converter for Automotive LED Driver Applications
摘要： Silicon photonic interconnect (SPI) is an attractive alternative for the power-hungry and low-bandwidth metallic interconnect in multiprocessor systems-on-chip (MPSoCs). When employing SPIs for wavelength-division multiplexing (WDM)-based applications, it is essential to precisely align the central wavelengths of different photonic devices (e.g., photonic switches) to achieve a reliable communication. However, SPIs are sensitive to fabrication nonuniformity (a.k.a. fabrication process variation), which results in wavelength mismatches between devices, and hence performance degradation in SPIs. This work presents a computationally ef?cient and accurate bottom-up approach to study the impact of fabrication process variations on passive silicon photonic devices and interconnects. We ?rst model the impact of process variations at the component level (i.e., strip waveguides), then at the device level (i.e., add-drop ?lters and photonic switches), and ?nally at the system level (i.e., passive WDM-based SPIs). Numerical simulations are performed not only to evaluate the accuracy of our method, but also to demonstrate its high-computational ef?ciency. Furthermore, our study includes the design, fabrication, and analysis of several identical microresonators to demonstrate process variations in silicon photonics fabrication. The ef?ciency of our proposed method enables its application to large-scale passive SPIs in MPSoCs, where employing time-consuming numerical simulations is not feasible.
关键词： wavelength-division multiplexing,Fabrication non-uniformity,reliability,silicon photonic interconnects
更新于2025-09-23 15:19:57
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Reliability Analysis of Distributed Grid-connected Photovoltaic System Monitoring Network
摘要： A large amount of distributed grid-connected Photovoltaic systems have brought new challenges to the dispatching of power network. Real-time monitoring the PV system can efficiently help improve the ability of power network to accept and control the distributed PV systems, and thus mitigate the impulse on the power network imposed by the uncertainty of its power output. To study the reliability of distributed PV monitoring network, it is of great significance to look for a method to build a highly reliable monitoring system, analyze the weak links and key nodes of its monitoring performance in improving the performance of the monitoring network. Firstly a reliability model of PV system was constructed based on WSN technology. Then, in view of the dynamic characteristics of the network’s reliability, fault tree analysis was used to judge any possible reasons that cause the failure of the network and logical relationship between them. Finally, the reliability of the monitoring network was analyzed to figure out the weak links and key nodes. This paper provides guidance to build a stable and reliable monitoring network of a distributed PV system.
关键词： Monitoring Network,Fault Tree Analysis,Photovoltaic System,WSN,Reliability
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE Pulsed Power & Plasma Science (PPPS) - Orlando, FL, USA (2019.6.23-2019.6.29)] 2019 IEEE Pulsed Power & Plasma Science (PPPS) - Pulsed RF Signal Irradiation Using a Low Voltage NLTL Coupled to a DRG Antenna
摘要： Field-programmable gate arrays (FPGAs) have been shown to provide high computational density and efficiency for many computing applications by allowing circuits to be customized to any application of interest. FPGAs also support programmability by allowing the circuit to be changed at a later time through reconfiguration. There is great interest in exploiting these benefits in space and other radiation environments. FPGAs, however, are very sensitive to radiation and great care must be taken to properly address the effects of radiation in FPGA-based systems. This paper will highlight the effects of radiation on FPGA-based systems and summarize the challenges in deploying FPGAs in such environments. Several well-known mitigation methods will be described and the unique ability of FPGAs to customize the system for improved reliability will be discussed. Finally, two case studies summarizing successful deployment of FPGAs in radiation environments will be presented.
关键词： radiation effects,radiation hardening,Fault-tolerant systems,integrated circuit reliability,field programmable gate arrays
更新于2025-09-23 15:19:57
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Impact of environmental variables on the degradation of photovoltaic components and perspectives for the reliability assessment methodology
摘要： Backsheet cracking has been a major issue observed in the field; however, standardized qualification tests, such as IEC61215, are inadequate to reliably identify such failures of PV modules due to the lack of the critical weathering factors applied sequentially or in combination, such as those found in the service environments. To address this problem, we investigated the effects of various environmental variables on the degradation and failure behaviors of the polyamide-based backsheet in PV modules retrieved from five different locations, encompassing a variety of climates, including humid subtropical, hot-summer Mediterranean, tropical savanna climate and hot arid. The correlations between the degradation indicators and the weathering variables were further demonstrated by principle components analysis (PCA). We found strong relationships between: carbonyl formation and reflected solar radiation; hydroxyl formation and module temperature; yellowness and NO2 concentration, while no simple correlation could be found between a specific weathering factor and cracking. By introducing additional stress factors to the aged polyamide-based backsheet films with the novel “fragmentation test”, we successfully reproduced the field cracking behaviour. This study has demonstrated that different degradation modes of PV components respond differently to the environmental stresses encountered in service. Thereby, any accelerated laboratory test based on a single set condition or lacking key environmental variables would be inadequate to assess the long-term performance of PV modules and components. A new reliability-based methodology is proposed to quantitatively link laboratory testing with field results for the service life prediction of PV materials.
关键词： Reliability,Backsheet,Photovoltaic modules,Principle components analysis,Polyamide,Weathering
更新于2025-09-23 15:19:57
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Optical Communications and Networks
摘要： Due to energy and throughput constraints of visual sensing nodes, in-node energy conservation is one of the prime concerns in visual sensor networks (VSNs) with wireless transceiving capability. To cope with these constraints, the energy ef?ciency of a VSN for a given level of reliability can be enhanced by recon?guring its nodes dynamically to achieve optimal con?gurations. In this paper, a uni?ed framework for node classi?cation and dynamic self-recon?guration in VSNs is proposed. The proposed framework incorporates quality-of-information (QoI) awareness using peak signal-to-noise ratio-based representative metric to support a diverse range of applications. First, for a given application, the proposed framework provides a feasible solution for the classi?cation of visual sensing nodes based on their ?eld-of-view by exploiting the heterogeneity of the targeted QoI within the sensing region. Second, with the dynamic realization of QoI, a strategy is devised for selecting suitable con?gurations of visual sensing nodes to reduce redundant visual content prior to transmission without sacri?cing the expected information retrieval reliability. The robustness of the proposed framework is evaluated under various scenarios by considering: 1) target QoI thresholds; 2) degree of heterogeneity; and 3) compression schemes. From the simulation results, it is observed that for the second degree of heterogeneity in targeted QoI, the uni?ed framework outperforms its existing counterparts and results in up to 72% energy savings with as low as 94% reliability.
关键词： visual sensor networks,dynamic reconfiguration,node,3D field-of-view modelling,classification,energy optimization,quality-of-information,reliability analysis
更新于2025-09-23 15:19:57
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[IEEE 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) - Berlin, Germany (2019.6.23-2019.6.27)] 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII) - Manipulation of Biomolecules Into Nanogap by Plasmonic Optical Excitation for Highly Sensitive Biosensing
摘要： This paper presents an apparatus and methodology for an advanced accelerated power cycling test of insulated-gate bipolar transistor (IGBT) modules. In this test, the accelerated power cycling test can be performed under more realistic electrical operating conditions with online wear-out monitoring of tested power IGBT module. The various realistic electrical operating conditions close to real three-phase converter applications can be achieved by the simple control method. Further, by the proposed concept of applying the temperature stress, it is possible to apply various magnitudes of temperature swing in a short cycle period and to change the temperature cycle period easily. Thanks to a short temperature cycle period, test results can be obtained in a reasonable test time. A detailed explanation of apparatus such as configuration and control methods for the different functions of accelerated power cycling test setup is given. Then, an improved in situ junction temperature estimation method using on-state collector–emitter voltage VC E O N and load current is proposed. In addition, a procedure of advanced accelerated power cycling test and test results with 600 V, 30 A transfer molded IGBT modules are presented in order to verify the validity and effectiveness of the proposed apparatus and methodology. Finally, physics-of-failure analysis of tested IGBT modules is provided.
关键词： insulated-gate bipolar transistor module,physics-of-failure,power cycling test,lifetime model,Failure mechanism,reliability
更新于2025-09-23 15:19:57
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[IEEE 2019 International Conference on Electrical Engineering and Computer Science (ICECOS) - Batam Island, Indonesia (2019.10.2-2019.10.3)] 2019 International Conference on Electrical Engineering and Computer Science (ICECOS) - Solar Cell-Powered UAVs for Marathon Flights as a Geographic Data Retrieval Tool
摘要： On 1 September 2009, as part of a new node-based market implementation, the Electric Reliability Council of Texas transitioned from its then-prevalent data modeling processes to a new network model management system (NMMS) for model data management. This change represented the culmination of nearly four and a half years of planning and development. The NMMS provided several improvements over the then-current data maintenance processes. This paper describes some of the existing issues facing the power industry in the area of power system model data management and explains how solutions to these issues were addressed conceptually in the development of and incorporated into the final design of the NMMS. Further, this paper explains how these concepts of design and usability are now gaining wider recognition and acceptance from the industry.
关键词： power system modeling,Common information model (CIM),Electric Reliability Council of Texas (ERCOT)
更新于2025-09-23 15:19:57