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91.
基于故障树法的电路板故障诊断研究 总被引:1,自引:0,他引:1
电路板的故障检测与定位一直是十分复杂困难的工作。针对某装备的控制电路,设计了一个故障诊断系统,以电压信号作为激励信号,而以电路板系统电压电流等响应信号作为输出。建立了电路分析的故障树,并根据故障树建立了相应的故障字典,进行了典型电路板的故障定位与搜寻等研究。通过仿真分析表明,该基于故障树方法的电路板故障诊断是可行的。 相似文献
92.
智能电力监控系统在电气节能中的应用 总被引:1,自引:0,他引:1
基于“透明建筑配电“策略的智能电力监控系统是具有互联网功能的电力监控系统,是智能建筑的重要组成部分.本文以施耐德电气PowerLogic电力监控系统为例,论述了智能电力监控系统在智能建筑和电气节能方面的主要功能和应用. 相似文献
93.
自旋系统是一类基于电子自旋工作的器件,具有高速、低功耗等优点,其中磁存储器被认为是下一代存储器的领跑者之一。二维材料有着天然的界面性能优势,接近微缩极限的尺寸特点,以及二维结构带来的物理特性,在自旋系统中有望得到广泛运用。本文概述了二维材料在自旋领域的最新研究进展,介绍了一些常见的二维磁性材料,讨论了基于二维材料的二维自旋器件,以及回顾了基于二维材料的磁性调控,最后总结了这一领域仍然面临的挑战,并对未来发展进行了展望。 相似文献
94.
Chia-Lung Tsai Cheng-Lung Tsai Guan-Ru He Ting-Hong Su Chang-Feng You Yow-Jon Lin 《Solid-state electronics》2011,61(1):116-120
In this study, the current-voltage characteristics of the AlCdO/unpolished p-type Si and AlCdO/polished p-type Si Schottky diodes with and without light illumination were examined. It is found that the Schottky barrier height (the series resistance) of the AlCdO/unpolished p-type Si Schottky diode is higher (lower) than that of the AlCdO/polished p-type Si Schottky diode. The power conversion efficiency of the AlCdO/p-type Si devices in the light (AM 1.5 G, 100 mW/cm2) was improved by increasing built-in potential at the AlCdO/p-type Si interfaces and reducing the device series resistance and surface reflectivity. It is shown that the device surface roughness plays an essential role in improving the device performance. 相似文献
95.
Marco Barink Dennis van den BergIryna Yakimets Peter GiesenJohannes A.W. van Dommelen Erwin Meinders 《Microelectronic Engineering》2011,88(6):999-1005
A numerical model was developed to simulate the micro-deformations of a polymeric substrate due to lithographic processing of different layers of a transistor-like structure. The results of the model were validated with the results from experiments. The model, a mechanical-thermal-hygroscopic model, takes into account the dimensional effects of temperature, moisture and stresses. It also includes the temperature dependent visco-elastic behaviour of the polymer substrate. The model can be used to predict overlay accuracies between different functional layers introduced by the lithographic process. It can also be used to understand the underlying processes such that it provides a tool to improve the overlay accuracy during actual processing. 相似文献
96.
郭远东 《电子产品可靠性与环境试验》2011,29(1):55-58
通过介绍EN 55025:2008版与EN 55025:2003版的差异,说明EN 55025:2008版标准在测量范围、测量方法、合格性判定以及供电电源电压范围等方面的新要求. 相似文献
97.
98.
Stephan van Reenen Piotr Matyba Andrzej Dzwilewski René A. J. Janssen Ludvig Edman Martijn Kemerink 《Advanced functional materials》2011,21(10):1795-1802
Incorporation of ions in the active layer of organic semiconductor devices may lead to attractive device properties like enhanced injection and improved carrier transport. In this paper, we investigate the effect of the salt concentration on the operation of light‐emitting electrochemical cells, using experiments and numerical calculations. The current density and light emission are shown to increase linearly with increasing ion concentration over a wide range of concentrations. The increasing current is accompanied by an ion redistribution, leading to a narrowing of the recombination zone. Hence, in absence of detrimental side reactions and doping‐related luminescence quenching, the ion concentration should be as high as possible. 相似文献
99.
Martijn Kuik Gert‐Jan A. H. Wetzelaer Jurre G. Laddé Herman T. Nicolai Jurjen Wildeman Jörgen Sweelssen Paul W. M. Blom 《Advanced functional materials》2011,21(23):4502-4509
The effect of on‐chain ketone defects on the charge transport of the polyfluorene derivative poly(9,9‐dioctylfluorene) (PFO) is investigated. Using MoO3 as ohmic hole contact, the hole transport in a pristine PFO diode is observed to be limited by space‐charge, whereas fluorenone contaminated PFO (PFO‐F) is shown to be trap limited by the occurrence of an exponential trap distribution with a trap depth of 0.18 eV. The electron transport in PFO is also observed to be trap limited, but in order to describe the electron transport of PFO‐F, an additional trap level with a depth of 0.46 eV must be introduced. The obtained energy levels of the fluorenone trapping sites are in close agreement with cyclic voltammetry (CV) measurements reported in literature. As a result, the fluorenone defects are shown to simultaneously act as hole‐ and electron trap. Moreover, through ideality factor measurements, the green emission associated with these defects is observed to originate from trap‐assisted recombination. 相似文献
100.
Marcel Müri Bernd Gotsmann Yann Leroux Marius Trouwborst Emanuel Lörtscher Heike Riel Marcel Mayor 《Advanced functional materials》2011,21(19):3706-3714
Due to the increasing importance of modified electrodes for many applications in nanotechnology, including molecular electronics, bioelectronics, and sensors, there is a need to find ways to chemically attach suitable molecular films onto the electrodes. Combining the electroreduction of aryl diazonium salts with the Sonogashira cross‐coupling reaction, a new modular technique to modify electrodes is presented. The new technique allows a wide range of functional groups to be introduced onto electrode surfaces with high surface coverage by the functional subunit. Various organic subunits, including redox chromophores, are successfully attached to platinum electrodes. The corresponding films are characterized using cyclic voltammetry, X‐ray photoelectron spectroscopy, atomic force microscopy, and contact‐angle measurements. The electroreduction of diazonium salts is successfully achieved on a broad variety of conducting and semiconducting surfaces, which shows that the technique is applicable to a broad variety of substrates. 相似文献