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.     

基于整型小波变换的遥感图像压缩

对给定的遥感图像采用基于“提升”（Lifing)算法的整型小波变换，然后对变换后的小波域图像进行编码。在小波域编码时，采用逐次近似量化和LZ77方法编码。当量化门限较高时，则有用EZW方法直接对小波域上的图像进行编码，当门限较低时，则对EZW编码后的残差信息进行LZ77编码，文章用上述方法实现了遥感图像的无损压缩，提高了图像的压缩效果。     

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。     

基于GPS/GPRS的车载卫星定位系统的研究

根据现代智能变通系统的实际需求，设计了一种基于GPRS的车载卫星定位系统，系统采用单片机作为处理器，通过GPRS网络建立无线通信链路，把车载移动终端的GPS定位信息传到Internet网上的服务器，实现在线实时监测车辆行驶各类信息；详细阐述了车载定位系统的工作原理和车载终端系统硬件设计，介绍了单片机软件编程以及PPP，TCP／IP等协议栈的建立，实际运行结果表明，系统达到设计要求，实现了控制中心实时监测车辆行驶状态，加强了企业对车辆的监控和管理。     

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。