The Region 1 & 3 Broadcasting‐Satellite Service Plan after WRC‐03

The 1977 Broadcasting‐Satellite Service (BSS) Plan for Region 1 & 3 had been widely acknowledged to be out‐of‐date by the late 1980s. Development of digital modulation in the early 1990s provided an opportunity to update the technical provisions of the Plan to make it more economically viable. After a decade of work and three World Radiocommunication Conferences (WRCs), the revision of Region 1 & 3 BSS Plan was finally completed in 2003. The new Plan increased channel assignments from 5 to 10 analog‐equivalent channels for each country in Region 1, and from 4 to 12 channels for each country in Region 3. Yet, despite the increase in capacity, the new Plan is surprisingly similar to the original one in terms of the technical parameters. It is still based on national coverage, and the channel plan, orbital location, orbital spacing, and polarization are also the same. As a result, the new Plan is no more economically viable to implement than the old. To create economically viable BSS systems would most likely require modifications to the assignment in the Plan. Yet, modification procedures were made more difficult to apply after replanning. Less future implementation of BSS networks than would otherwise have occurred can be expected, and an inefficient usage of these frequency bands will likely result. On the other hand, less implemented systems will mean more capacity set aside for future use. This is important for countries that currently do not have satellite operations. In the end, BSS replanning reflects the eternal conflict between efficient usage and guaranteed future access. Copyright © 2005 John Wiley & Sons, Ltd.     

The seismic kernel system — a large-scale exercise in fortran 77 portability

The portability of software has become a major commercial issue in recent times. Such portability does not come easily, as few if any computer languages are really portable in practice. An additional complicating factor, especially in the commercial environment, is that the resulting software must be efficient. This paper describes the design and successful implementation of a 500,000+ line portable FORTRAN 77 package for the processing of seismic data. The package exhibits demonstrably high efficiency on a wide variety of machines from minicomputers to the largest supercomputers. Experiences gained during this exercise throw much light on the integration of the various thought processes which occur during the software engineering cycle, especially the notion of locality.     

基于AD7884的分离脱落电连接器机械分离力测试台的设计

基于分级型模数转换器AD7884对分离脱落电连接器的分离力进行测量,采用8位单片机W77E58与之接口,进行数据处理并通过485串口传输到上位机。实现了对分离脱落电连接器的分离力进行测量,系统运行稳定,且与上位机数据交互简单、可靠。     

低熵图像序列无损压缩

大规模的云渲染技术带来了大量的三维图形渲染数据。为了减小集群渲染产生的图像序列数据的传输以及存储代价,针对渲染图像序列低熵的特点,基于字典编码技术提出了降低数据局部复杂性的无损数据压缩方案。该方案通过数据重排技术来大大提高数据的局部冗余度,从而提高数据无损压缩效率。为了进一步解决大规模图像序列的压缩耗时问题,提出了一种云计算平台上的分布式图像压缩处理方案,充分利用现有云计算中Map/Reduce计算模型实现了分布式编码方案。实验结果证明,对于渲染产生的大规模低熵图像序列,提出的方案能够有效提高编码率并减少编码时间。     

77B 钢奥氏体连续冷却转变曲线(CCT图)

采用Gleeble-1500热模拟机测定了77B钢在不同冷速下连续冷却转变的膨胀曲线，结合组织观察和硬度测定，获得了该钢的连续冷却转变曲线；研究了其连续冷却转变产物的组织形态，比较了其与同类转变曲线的差别。     

证券广播、信息处理系统的设计与实现

本文提出一种证券广播、信息处理系统，能实时的完成电脑证券系统的所有功能又无需上网。使用不同的接口．可应用于电脑系统和电视系统。本文主要从两个方面论述了该系统的原理，以W77E58为主芯片的证券信息广播服务器系统和以DALLS80C320为主要芯片的证券信息处理（接收、分析、交易）系统，并在此基础上，详细介绍了实现证券信息广播和接收、分析、交易的方法和原理。     

基于GPRS的电能远程抄表系统的设计与实现

通过中国移动通信有限公司的通用无线分组业务(general packet rad io service,GPRS)网络,可实现电力系统的远程数据采集和传输。介绍了基于GPRS技术的电能远程抄表系统的结构和工作原理,提出了一种基于Sony Ericsson Mob ile Commun ications公司GR47模块和W inbond公司W 77E58微控制器的电能远程抄表系统,从系统的硬件结构、软件设计和后台的接收程序设计等方面分析了该系统的实现方案。     

基于Lonworks的仿人智能PID控制器的设计

文中结合Lonworks现场总线和单片机各自的技术优势，详细地论述了利用仿人智能PID控制算法设计一块具有强大通信功能的智能仪表的方案。该方案既克服了传统PID控制存在的缺陷，又将测控技术和网络技术的特点巧妙地结合起来，有效地解决了工业用仪表信息共享的“孤岛”问题，同时也为进一步实现工业远程实时控制提供了极大的便利。文中详细地阐述了仪表的硬件电路设计、仿人智能PID控制的算法实现、软件程序流程图以及部分源代码，这些在实际应用中均具有较高的实用价值和较为广泛的应用前景。     

基于W77E58的多路数据采集系统的设计与实现

为了对实际信号进行监测,设计了以W77E58微控制器为核心的多路数据采集系统,介绍了系统总体结构,阐明了模拟量采集的硬件和软件设计方法,给出了具体的电路图和软件程序,经实际测试表明,该系统具有采集精度高、功耗低、抗干扰能力强、通用性好的特点。     

C51环境下W77E58 Watchdog的应用

在单片机的应用中,逐步引入了高级语言,C语言就是其中一种.但是如果C语言应用不当很可能会引起单片机系统无法正常运行,重点介绍了利用C51作为编程语言在使用W77E58时,如果程序在定义全局变量或静态变量时进行了初始化会对Watchdog的复位产生的影响及其解决方法.