支持IA-32保护模式的存储管理单元的设计与实现

研究支持IA-32保护模式的存储管理单元的设计，并在龙腾C2微处理器中实现了该存储管理单元。分析了段页式存储管理单元的地址变化机制和IA-32保护模式下的存储保护机制，详细讨论了存储管理单元的分段单元和分页单元的设计。以及存储管理单元在流水线中的控制机制，并就存储管理单元的关键路径进行了结构优化。仿真验证和综合的结果表明．该存储管理单元的设计满足龙腾C2微处理器的功能和性能要求。     

相控阵天线的耦合激励系数及盲点研究

为了深入探讨相控阵天线单元间的相互耦合,以阵列天线单元S参数为基础,分别分析了振子形式辐射单元和缝隙形式辐射单元组成阵列的辐射单元之间的耦合关系,并利用天线单元的耦合激励系数分析计算了阵中单元的有源辐射方向图。对阵列中每个单元的耦合激励系数的幅度和相位进行了分析,发现平行排列单元和轴向排列单元的耦合激励系数的相位存在差异,平行排列时激励单元与相邻单元间的相位相差较小,这种差异是阵列产生盲点的主要因素。     

基于PLC的自动化生产线控制系统

本文介绍了一种基于OMRON小型PLC的自动化生产线的控制系统,它由输送分拣单元、机器人搬运单元、物料归正单元、加工单元、装配单元五部分组成,文中叙述了五个单元的输入输出分配和工作流程。     

107 cm荫罩式PDP实际单元和放大单元放电特性的研究

利用基于PIC-MCC(Particle in cell-Monte Carlo collision)模型的OOPIC-PRO软件计算了107 cm荫罩式PDP实际单元和放大单元的放电,模拟结果表明相似放电单元具有相同的伏安特性,放电相对应时刻的空间粒子浓度分布相同,从数值实验角度验证了气体放电的重要定律:相似定律.在理论模拟的基础上,利用实际单元和放大单元的实验测试系统,测量并比较了放大单元和实际单元的放电电流,结果表明放大单元和实际单元的放电电流强度相当,但实际单元较放大单元的放电快约20倍.     

基于Y 型频率选择表面的小型化设计*

设计了一种基于Y型的带阻型小型化频率选择表面,其单元的等面积正方形尺寸仅为0.057λ0×0.057λ0,厚度仅为0.021λ0。新型单元通过对传统Y型结构的分支向内进行规则的弯折来增大Y型单元的臂长,增加单元的谐振长度,从而增大了单元的等效电感与电容,提升了空间利用率。单元面积的减少,提高了单元的小型化效果,同时减小了单元间的距离,使频率选择表面具有较好的角度稳定性。仿真和测试结果表明,这种小型化单元对于不同角度入射的TE和TM波都具有很好的稳定性,其单元面积比谐振频率相同的传统Y形单元的面积减小了约96.3%,具有良好的带阻特性。     

基于光无线融合的用电信息采集通信系统

提出了一种基于射频拉远光无线融合技术的LTE230M无线通信方案,构建用电信息采集通信系统.利用射频拉远技术将传统的基站拆分为基站单元与射频单元,设计了基带单元与射频单元的模块结构,研究了系统的组网结构与特点,总结了基带单元与射频单元安装选址的原则.     

基于ARM的自助货柜系统设计研究

不断改善用户体验是快递企业加强自身竞争力的重要举措。针对送货时遇到用户不在的情况,提出了基于ARM的自助货柜系统设计。系统主要由ARM主控芯片、RFID身份验证单元、条码扫描单元、信息输入/显示单元、GPRS通信单元、视频监控单元、报警单元、货柜机械控制单元等部分构成,实现了自助取件功能,具有一定的实用价值。     

高速冲孔单元设计

在分析如何提高生瓷带打孔机打孔速度的基础上,论述了高速冲孔单元的实现途径;并通过与普通冲孔单元的试验数据对比,得出了高速冲孔单元各项指标均优于普通冲孔单元,达到了设计要求,高速冲孔单元的研制显著地提高了生瓷带打孔机的性能.     

一种基于DSP和FPGA的图像处理系统

设计了一种以FPGA为数据采集逻辑控制单元,以DSP为高端图像处理单元的数字图像处理系统。介绍了该系统的硬件组成、工作原理。从视频编码单元、图像处理单元和视频输出单元对整个系统的构成和设计进行了描述,分析了系统设计时的各个关键技术环节。     

基于增强型51单片机的智能药箱的设计

介绍了一种基于STC90C516RD＋单片机的智能药箱的设计,主要结构有主控单元、时钟单元、报警单元、显示单元等。显示单元显示药品的相关信息及服药时间,有利于用户及时掌握各项信息;报警单元可以在规定的时间内进行报警提醒,保证了用户能够及时服药。     

单位阶跃响应的时域求解方法

我们国多数教材中重点讨论系统的单位冲激响应时域求解方法,然后利用阶跃响应与冲激响应的微积分关系求解系统阶跃响应,关于直接求解单位阶跃响应的时域方法总结较少。本文分别从冲激响应与阶跃响应关系、微分方程求解以及时域规范化方法的角度出发,归纳了连续时间系统单位阶跃响应求解方法,并以实例说明其正确性。     

Cost-benefit analysis of a one-server two-nonidentical-unit cold standby system with repair and preventive maitenance

The paper deals with the cost-benefit analysis of a one-server two-nonidentical-unit cold standby system with repair and preventive maintenance (PM). The system consists of two units, one main unit and one secondary unit. If both units are up, the main unit is always in operation and the secondary unit is in cold standby. The secondary unit operates only when the main unit is taken off for repair or PM. There is no PM on the secondary unit. On the main unit, PM is of the age replacement type. Using regenerative point technique, the point-wise availability of both main and secondary units is obtained. The busy period of the server is broken up into the time spent for repair of the main unit, time spent for repair of the secondary unit and time spent for PM of the main unit. It is assumed that all revenues are earned and costs are incurred at a linear rate with time. The s-expected net revenue (revenue minus costs) in [0, t) is obtained.     

Analysis of a single unit system with helping unit

This paper considers a single unit (hence forth we call it a main unit) system with a helping unit. Initially both units are operative. The functioning of the main unit is assumed to be dependent on the helping unit, if the helping unit is in the operative mode, otherwise the main unit works independently with an increasing failure rate. The main unit can fail either partially or totally, while the helping unit can fail only totally. Failure times are assumed to follow negative exponential distributions, while the repair-time distributions are general. Important characteristics related to the system are obtained by using the regeneration point technique.     

大型机组发变组保护配置研究

本文主要对大型机组发变组的接线方式、保护技术现状进行分析,并提出了大型机组发变组保护配置原则及注意的问题.     

Two-unit redundant system with inspection and adjustable rates

A two-unit redundant system is studied, in which one unit is operative and the other is a warm standby which replaces the operative failed unit instantaneously. To increase system availability, the failure rate of the operative unit and the repair rate of the failed unit adjust automatically according to the state of the standby unit. Also, after repair of the operative failed unit it is sent for inspection to decide whether the repaired unit is perfect or not. If the repaired unit is found to be imperfect, it is sent for post repair. Using a regenerative point technique in the Markov renewal process, several reliability characteristics of interest to system designers and operation managers are obtained.     

免疫层析试条量化检测系统研究

介绍了一种用于免疫层析试条量化检测的光学检测系统。该系统基于光反射原理，包括光电检测单元、信号采集与处理单元、微处理器及数据存储、显示输出、计算机通讯和按键输入等部分。它采用光纤作为光传输媒介，同时获取检测线和质控线的光学信号，分析其吸收率，获得样品溶液中待测物的浓度。系统具有体积小、成本低、适于多种免疫层析试条定量检测等优点，在临床检测上有着广阔的应用前景。     

免疫层析试条量化检测系统研究

介绍了一种用于免疫层析试条量化检测的光学检测系统。该系统基于光反射原理,包括光电检测单元、信号采集与处理单元、微处理器及数据存储、显示输出、计算机通讯和按键输入等部分。它采用光纤作为光传输媒介,同时获取检测线和质控线的光学信号,分析其吸收率,获得样品溶液中待测物的浓度。系统具有体积小、成本低、适于多种免疫层析试条定量检测等优点,在临床检测上有着广阔的应用前景。     

Cost analysis of a two-unit cold standby system with two types of operation and repair

This paper deals with the cost analysis of a single-server two-identical unit cold standby system and two types of repair—minor and major. The unit requires minor repair if it fails for the first time. The major repair is required only when the unit fails after the minor repair. Upon minor repair the unit does not work as a normal unit but as a quasi-normal unit which has a different (increased) failure rate from that of a new one. Upon major repair the unit works as good as new (normal unit). Failure time distributions are negative exponential whereas repair time distributions are general. Using regeneration point technique the system characteristics of interest to system designers and operations managers have been obtained.     

A two-unit priority standby system subject to random shocks and Releigh failure-time distribution

This paper deals with the cost-benifit analysis of a two-unit priority standby system subject to random shocks. The priority unit gets preference both for repair and operation over the ordinary unit and has three modes- Normal, Quasi-normal and Total-failure. The ordinary unit has only two-modes- Normal and Total-failure. The distributions of shock-time, repair-time of the ordinary unit and failure time of the priority unit are negative exponential. The distribution of the repair-time of the priority unit is taken to be general while the time to failure of ordinary unit follows Releigh distribution. Various characteristics related to system effectiveness have been obtained by using the regenerative point technique.     

基于FPGA的数字中频接收和恢复系统设计

介绍一种数字中频恢复系统,该系统分为光纤接收单元、FPGA核心单元和QDUC单元。光纤接收单元采用高速串行器／解串器TLK1501,完成高速串行数据的串行转换。FPGA核心单元对数据进行解码、检验、配置TLK1501和AID957。QDUC单元实现基带信号的上变频和D／A转换。测试结果证明,系统具有实时性好、工作稳定、抗干扰性强的优点。