西部城乡中学体育教育资源配置的系统优化

本文对西部城乡中学体育教育资源的配置情况进行了分析,并对其配置进行了优化分析。体育资源配置的优化分析采用基于B/S结构的资源配置系统,并对系统进行了设计,对TCP/IP协议这项技术进行相关分析。     

宽频带吸波材料的设计方法

从目前对吸波材料薄、轻、宽的要求出发,介绍了展宽吸波频带的途径,总结了国内外设计宽频带吸波涂层的几种 方法,研究了其吸波机理,具体实例和方法,各种方法在GHz频率范嗣上得到了良好的宽频带特性。     

High-Selectivity Switched-Capacitor Bandpass Filter with Quasi-Continuous Quality Factor Tunability

This paper describes the design and implementation of a second-order switched-capacitor (SC) bandpass (BP) filter with very wide quality factor (Q) programmability range. The filter selectivity is digitally programmed by varying the effective sampling frequency of an SC branch, without modifying any capacitor value. The proposed approach allows a quasi-continuous Q-factor tunability avoiding, in principle, the inherent quantization error associated to any traditional programming technique. Automatic Q-factor tuning is performed by using a scheme based on an amplitude-locking loop approach. Experimental results obtained from a 0.8-m CMOS integrated prototype demonstrate the versatility of the proposed technique for high-Q SC BP filters.     

On Maximizing the Coverage of Catastrophic and Parametric Faults

The purpose of this paper is to analyze an optimization method to improve the testability of structural and parametric faults in analog circuits. The approach consists of finding an optimum sub-set of tests which maximizes the fault coverage with minimum cost. The method is based on covering a discrete set of intervals by taking advantage of strategies effectively used in digital synthesis. A simple application example is given to illustrate the proposal by studying the fault coverage obtained using different test sets on the ITC97 benchmark op-amp.     

Design of Fully Balanced Analog Systems Based on Ordinary and/or Modified Single-Ended Opamps

The system architectures, which allow a high performance fully balanced (FB) system based on ordinary/modified single-ended opamps to be implemented, are investigated and the basic and general requirements are formulated. Two new methods of an FB analog system design, which contribute towards achieving both a high performance IC system implementation and a great reduction of the design time are presented. It is shown that a single-ended system based on any type of opamp (rail-to-rail, constant g _m , etc.), realized in any technology (CMOS, bipolar, BiCMOS, GaAs), can be easily and effectively converted to its FB counterpart in a very practical way. Using the proposed rules, any FB system implementation with opamps (data converter, modulator, filter, etc.) requires only a single-ended system version design and the drawbacks related to a conventional FB system design are avoided. The principles of the design are pointed out and they are verified by experimental results.     

激光主动照明在轻武器立靶中的应用研究

在轻武器CCD立靶时采用激光主动照明技术,可以有效提高探测器的信噪比及系统捕获率,是轻武器立靶技术的关键.文中在交汇测量原理的基础上,通过建立轻武器CCD立靶测量系统,选择出大功率列阵列半导体激光器,计算出子弹的光谱亮度.深入研究了激光照明,在轻武器测量中应用的关键技术.     

破坏性物理分析技术所面临的挑战和对策

破坏性物理分析（DPA）作为一种有效的电子元器件批质量评价方法,近年来对促进我国元器件制造工艺的提高起到了很大的作用,对当前DPA技术所面临的一些问题进行了分析,并提出解决这些同题的方法和建议。     

拉盖尔-高斯光束在含拓扑绝缘体周期薄膜中的传输特性

基于平面角谱扩展法和4×4矩阵传输理论,研究了拉盖尔-高斯光束(LGB)在含拓扑绝缘体(TI)周期性层状薄膜中的反射和透射特性,对线偏振的LGB入射到周期性层状薄膜中的反射场和透射场的强度分布进行了分析和详细讨论。研究结果表明,TI的拓扑磁电极化率(TMEP)和薄膜的周期个数对强度分布有很大影响,通过改变TMEP或周期个数可以操纵涡旋光的光场。所提方法不仅可以推广到其他含TI的多层介质体系,而且对进一步研究TI光子晶体中的光子能带结构和带隙具有一定的意义。     

GPRS技术在尾矿库远程监测系统中的应用

利用尾矿坝安全监测的自动化系统,实现实时监测监控是尾矿坝安全监测与管理的发展方向。在分析GPRS技术以及相关的TCP／IP技术的基础上,从系统总体设计的角度阐述了基于GPRS分组数据网络监控系统的设计,实现监控终端的软硬件设计、监控中心的软件设计、监控数据的采集与传输等。有助于矿山应急部门和相关单位进行实时监控、监视和预测尾矿的变化,为尾矿溃坝的应急指挥提供一种准确实时、成本低廉、全天候的监测手段。     

塑封半导体器件的可靠性保证措施

为了降低塑封半导体器应用于高可靠性产品领域中的质量风险,采用质量细化分析方法,针对塑封半导体器件本身在材料、结构等方面的特点,做了塑封半导体器件失效模式与机理的原理探讨。得出器件应用于产品前,应该进行温度适应性评估、二次筛选以及破坏性物理分析等先期工作。