红外车辆分离子系统的设计和性能分析

在机动车磁卡收费系统中,红外车辆分离子系统是一种重要设备,它是由平行等距红外线族构成的平面检测系统,其性能直接影响收费系统的正常运转。本文介绍该子系统的设计并对系统性能进行分析,得出:子系统采取相关检测技术后,不仅能有效地抑制外界干扰、噪声,还具有抗相邻红外信号干扰能力。     

Circuit multiplication equipment

This paper discusses the main issues relating to the configuration and equipment which are to be provided in earth-stations for implementing satellite links with digital circuit multiplication (DCM). Such an implementation is possible using either FDMA/TDM/PSK (continuous) or TDMA/PSK (burst mode) carriers. The main accent will be put in the paper on earth-stations operating with FMDA/TDM/PSK carriers (called IDR carriers by INTELSAT). As regards the RF/IF subsystem, it is shown that IDR and TDMA are very effective in terms of earth-station equipment as compared with conventional FDM/FM operation. As regards the communication subsystem—independently of the DCM equipment proper—a compact terminal, integrating all the signal processing and baseband functions is described.     

A High-Speed Data Acquisition Subsystem

Many problems inherent in signal acquisition using laboratory minicomputers are overcome by using a high-speed data acquisition subsystem incorporating a large buffer memory. A structured systems development methodology details the design stages of this subsystem and its interfaces. Key to implementation of the design is a dual-port solid-state disk (extended memory unit). The subsystem operates at acquisition rates up to 125 000 samples/s and can be extended to 500 000 samples/s; its design permits operation with any real-time or time-shared operating system.     

A Unique Exciter and RF Subsystem for ABC'S Mobile Satellite News Gathering Terminal the ABSCamp System

ABC's mobile Satellite News Gathering (SNG) terminal consists of an antenna subsystem, RF subsystem, video exciter, and voice/data communications package. This paper describes the RF subsystem and video exciter. The SNG terminal is designed to provide the highest quality video transmission available in a mobile configuration. The exciter subsystem includes a new direct coupled (DC) modulator to optimize spectrum utilization and transmission quality. The RF subsystem features 300 watt traveling wave tube (TWT) amplifiers integral to the antenna feed support assembly which maximizes the power output capability of the SNG terminal. The RF subsystem also includes RF combining facilities required to simultaneously transmit both video and voice/data carriers, and RF switching facilities required to select between alternate polarizations and test modes. The RF subsystem incorporates built in test equipment useful for testing the SNG uplink prior to live transmissions, and includes monitor and control facilities which allow an operator in the SNG truck to operate the RF equipment mounted on the antenna. The RF subsystem is designed to allow configuration as a fully redundant terminal. However, the RF subsystem may be configured for non-redundant operation where the reduced system availability is justified by the cost savings.     

城市视频监控系统解决方案

主要介绍了城市视频监控系统的组成,具体包括视频监控管理平台子系统、传输网络子系统、前端监控点子系统、监控中心子系统、无线传输子系统、可视化指挥子系统、安全平台子系统、运维管理子系统以及供电子系统等。设计力求通过此系统,充分利用视频技术和互联网技术,全面提升城市管理水平。     

基于ECDIS的船舶运动态势三维呈现

为保障多船舶近距离作业安全、提高船舶航行监控显示效果,设计和实现了船舶运动态势三维呈现子系统。通过从ECIDS获取船舶与近船目标的位置及运动参数等信息,解算出多船舶的运动态势参数,进而利用OpenGL技术实现船舶运动态势的三维呈现。演示结果表明,该子系统能有效地提供近距离多船舶运动态势的三维呈现,为船舶安全航行和作业提供决策辅助。     

应用PB实现计算机与外设的数据传输

在日益扩大的以计算机为中心的自动化控制管理系统中,通讯分系统在整个系统中所占比重越来越大．通讯质量的优劣,直接关系到系统的可靠性．数据传输能力、软件通讯协议的制定和通讯的实现也逐渐成为设计者必须解决的关键技术．以计量管理系统为例,结合设计实践,介绍了串行通讯的优点以及PB开发平台的基本特征,综述了系统功能和软、硬件组成,及应用程序要完成的任务．详细分析了串口通讯的工作流程,辅之以程序代码,探讨研究了数据传输的实现过程。     

新一代IC-CAM系统的功能改进

文章介绍了第二代集成电路计算机辅助制造(IC-CAM)系统。该系统在第一代IC-CAM系统基础上，全面改进了操作员予系统、调度员予系统和质检员予系统，实现了控制图的自动绘制和判剐，添加了流水周期控制模块；加强了设备管理予系统功能，形成了完整的设备运行记录，并具有提示定期维护的功能；新增了厂务管理予系统，实现了厂务环境数据的自动采集。使用该IC-CAM系统后，可有效地提高生产效率和产品质量。     

固态发射机中监控分机的设计

监控分机主要负责固态发射机的状态采集、双工切换及开关控制。为了实现通用化设计,监控分机分为电源、接口、信息处理、双工控制和开关机控制等模块。在实际应用中,可对上述模块进行灵活组合。文中介绍了监控分机的组成及工作原理,各模块的硬件设计,以及监控分机的软件设计。目前,该类型的监控分机已在多个产品中获得了成功应用。     

Design,Implementation, and Validation of KOMPSAT‐2 Software Simulator

In this paper, we present design features, implementation, and validation of a satellite simulator subsystem for the Korea Multi‐Purpose Satellite‐2 (KOMPSAT‐2). The satellite simulator subsystem is implemented on a personal computer to minimize costs and trouble on embedding onboard flight software into the simulator. An object‐oriented design methodology is employed to maximize software reusability. Also, instead of a high‐cost commercial database, XML is used for the manipulation of spacecraft characteristics data, telecommand, telemetry, and simulation data. The KOMPSAT‐2 satellite simulator subsystem is validated by various simulations for autonomous onboard launch and early orbit phase operations, anomaly operation, and science fine mode operation. It is also officially verified by successfully passing various tests such as the satellite simulator subsystem test, mission control element system integration test, interface test, site installation test, and acceptance test.     

基于Linux内核输入子系统的驱动研究

Linux因其完全开放的特性和稳定优良的性能深受欢迎,当推出了内核输入子系统后,更方便了嵌入式领域的驱动开放。介绍了Linux的设备驱动基础。详细阐述了基于Linux内核输入子系统下的设备驱动实现流程和构架。并以触摸屏为例,对驱动过程进行了分析研究。利用输入子系统的接口函数,将更方便的实现设备驱动。     

RFID电子门票解决方案(二)

继第二期本文的专题连载(一)之后,本文以验票和身份识别子系统、售票子系统、平台及数据库子系统、门票稽查子系统、隐形条码票子系统为主,并以停车场管理系统为例,详细介绍了广交会RFID们表解决方案的整体系统中的各个子系统的原理、构成和实际运转流程。     

LOCNET--A local area network using optical switching

A wide-band local area network using optical switching is presently being developed by the Heinrich-Hertz-lnsitut in Berlin (West). To ensure high reliability the system will be implemented as a star type network, divided into two subsystems. All switching within the system will be done by optical switching techniques. The wide-band subsystem will use Lithium-Niobate switching matrix elements, interconnected as a multistage space switch. Thus bit rate independent channels will be available with the ability to establish various wide-band services of the in-house area. The second subsystem makes use of a single-mode star coupler. Distributed circuit switching with fast switching capability and flexible data rates will be implemented, utilizing a TDM frame, that supports 63 narrow-band connections and a capacity of 8 Mbit/s for fast data services. To prevent typical disadvantages of distributed switching like line tapping and system disturbance, caused by malfunctioning system components, LiNbO3switches will be installed in front of and behind the star coupler. The single-mode star coupler will be implemented by cascading 2 × 2 star couplers, which are available as 3-dB couplers.     

NGN中的移动多媒体业务平台

IP多媒体子系统作为下一代网络的重要平台实现了固定网络与移动网络的无缝业务传递,丰富了移动多媒体的各种增值业务.IP多媒体子系统具有控制功能与承载能力分离、呼叫与会晤分离、应用与服务分离、业务与网络分离、移动网与互联网业务融合的主要特征,既适用于基于IP的移动多媒体业务,也适用于传统语音、数据和视频业务,是未来移动多媒体业务的发展方向.     

电梯群控预约控制算法

根据电梯群控系统特性，借鉴有关文献，提出了一种多目标控制算法：电梯群控预约优化算法，斤层增设目的层预约按钮，计算机能够从厅层监督系统和入检测子系统获取及时候梯人数、轿内拥挤度等信息，然后采集未的数据计算每个电梯的评价函数，最后选择适合的电梯响应斤层召唤。     

智能烟草工厂底层物联设备远程检修系统设计

针对烟草工厂底层物联设备检修体系落后,设备检修效率低的问题,设计智能烟草工厂底层物联设备远程检修系统.采集现场设备运行数据,并将采集的数据存储至设备故障经验知识库,应用故障专家子系统调用设备故障经验知识库的数据信息,实时监控现场设备运行状态;利用故障树最小割集的故障诊断方法,诊断智能烟草工厂底层物联现场设备,依据诊断结...     

基于联锁的I／O控制器的设计与实现

随着城市轨道交通系统的发展,信号系统已经成为城市轨道交通运营管理的中枢神经。作为信号系统之一的联锁,其主要作用是建立进路、进路解锁、控制道岔以及信号机的开放。基于联锁的I／O控制器实现了联锁与现场设备的通信。通过控制器,联锁可以实时地接收现场设备的状态,又可以将控制命令发送到相应的设备,所以控制器的性能与安全对整个系统也起着决定性的作用。文中从硬件以及软件两方面,对主备控制器的设计进行了深入分析。该控制器具有较高的安全性,将是城市轨道交通的一个很好的发展方向。     

浅析中职教务管理系统需求

随着我国大力发展中等职业教育,各校招生规模不断扩大,采用传统的教务管理模式将会浪费大量的人力、物力、财力,所以教务管理系统的开发已成为中职学习工作的重点。为了满足学校教务工作的需求,教务管理系统共设置了五大子系统：用户权限管理子系统、教学计划管理子系统、成绩管理子系统、学生考勤管理子系统、教材管理子系统,并对系统功能和非功能需求进行分析。     

Availability of non-independent main unit and N-unit series subsystem subject to shut-off rules

Two-unit series system subject to shut-off rules was treated by Osaki et al. [4]. Here a modified model is considered. The system is composed of a main unit and a n-unit series subsystem. The lifetime distributions of the main unit and that of any one of the N-unit of series subsystem are nonindependent. Two repair facilities are introduced. Failure of the main unit shuts off the operation of subsystem, but not vice versa. Failure of the main unit or the subsystem initiates the system shut down. For this model, the system availability is given by using the technique of the Markov renewal process. Moreover, the availability of Osaki's model and that of this model are compared. We found that the availability of this system is generally higher than that of Osaki's system.     

基于 B／S 的用户管理系统的研究与设计

介绍了基于B/S架构的用户管理系统,设计分为两个分系统,以前后台的方式运行。前台是一个综合业务系统,完成面向各类用户的各项运营功能及数据统计。后台负责处理订单,形成相应的授权信息,并将授权信息传送给CA系统。主要对前台系统的功能及数据表设计进行详细的说明,并介绍系统数据安全机制,最后将系统接入数字电视系统中联合测试,证明系统的可行性和有效性。