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针对关联模型在复杂电路板测试性分析中对不确定问题描述与分析的缺陷,提出了基于故障仿真和粗糙集的测试性分析方法.通过故障仿真生成条件属性集,利用粗糙集将其约简,最终形成分辨矩阵,从而评价电路的测试性水平.最后通过实例分析验证了方法的有效性. 相似文献
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为了解决深亚微米、SOC和低功耗电路中的测试问题,低功耗测试序列RSIC序列的生成方法得以研究和发展.文章提出关于RSIC序列生成电路的建模和分析理论.其研究特色是抽象出此类复杂电路固有特性的通用模型,建立一套简洁、准确的数学描述和分析方法,论证了此类电路的一系列特性,并通过片外测试的模拟结果来验证RSIC序列的低功耗.该研究结果为RSIC序列研究和应用提供了强有力的理论基础和分析方法. 相似文献
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在某固定无线电话机的入网测试过程中,电快速瞬变脉冲群(EFT)项目是EMC测试中的必测项目,12V线性适配器配合该话机测试不通过.本文描述了电路的改进过程和原理. 相似文献
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一个电路的测试性好意味着装备有较好的故障覆盖率,故障检测、隔离率和较低的虚警率,可以在较短的时间内,用最低的代价完成各级的测试和故障诊断任务。而部队装备又由许多电路组成,因此一个电路的测试性设计直接影响到装备的全寿命周期,良好的测试性设计已经成为武器装备发展的一个重要目标。为了提高部队装备的测试性,诸多学者极力在研究各种方法,文中提出一种基于多信号流图模型的测试性方法,系统阐述了多信号流图模型的基本分析方法及其建模,并以经典滤波放大电路为例,利用多信号流图模型分析了此电路的测试性问题。通过仿真分析说明了该方法对于装备有很高的可检测性以及故障检测率。 相似文献
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针对目前考虑不确定因素的测试性模型存在建模难度高、结构复杂、层次化建模困难、学习能力弱、不确定信息表达形式差的问题,面向电子设备提出了一种基于贝叶斯网络的测试性分层建模方法.以原有的贝叶斯网络模型与多信号流图模型为研究对象,对二者的参数、结构特点及优势短板进行分析,根据二者的互补性与测试性建模需求对贝叶斯网络模型进行改进.模型以故障、信号关系替代故障、测试关系,以信号节点间的连接表征故障传递,利用电路结构与层次划分确定模型结构,采用贝叶斯方法确立模型参数,运用贝叶斯网络推理能力对测试性指标进行计算.以放大滤波电路为例建立模型,通过模型计算测试性指标,并进行了证据处理测试,通过对比多信号模型可知,模型测试性指标计算准确、证据处理能力强,验证了建模方法的有效性与实用性. 相似文献
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首先,描述了装备测试性试验现状,发现了其中存在未考虑环境应力的问题;然后,分析了环境应力对机内自检测电路的影响;最后,提出了考虑环境应力的装备测试性试验方法.该方法在测试性试验过程中施加实际使用时的环境条件,完善了试验方案设计、试验准备工作和试验实施过程,最终达到了提高装备测试性试验结论的准确性的目的. 相似文献
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MiniSAT求解器运用到电路故障诊断系统时,能够将判断一个电路是否存在故障问题转换为可满足性问题.本文将全加器的行为模型及观测分别使用合取范式(CNF)形式文件描述,调用MiniSAT求解器判定可满足性.该方法自动化程度高,能处理大规模的运算电路,具有较强的查找错误能力. 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system. 相似文献
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Thomas M.Trexler 《半导体技术》2004,29(5)
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test. 相似文献
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The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation. 相似文献
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The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high. 相似文献
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Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 相似文献
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's. 相似文献
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Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it. 相似文献
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It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory. 相似文献
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A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working. 相似文献
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《中国通信》2014,(7)
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks 相似文献