一种数字电视条件接收系统的设计与实现

为支撑业务的安全开展，有线数字电视系统需提供一个安全可靠的加密系统，即条件接收系统。条件接收系统是对数字电视节目进行加密，以实现有线电视运营商对用户进行管理和收费。本文介绍了一种数字电视系统中的条件接收系统实现方案。     

数据转换系统中放大器的选择

随着广播电视技术的不断发展 ,模拟信号传输向数字信号传输的转换已成为必然。介绍模数转换系统中放大器的性能、关键技术 ,并就放大器的选择作详细探讨。     

Decision support for AIDS control programmes in Eastern Africa

The Acquired Immune Deficiency Syndrome (AIDS) constitutes the worst hazard to health care systems in Eastern Africa. Misallocation of scarce resources of AIDS Control Programmes will unavoidably lead to additional infections and casualties. The following paper discusses a system dynamics model which allows to assess the impact of different interventions on a pattern population in Eastern Africa. It becomes obvious that short- and long-term consequences of these programmes differ significantly. The optimal allocation of resources, therefore, is highly complex and calls for decision support systems to sustain AIDS control programmes.     

地市级电视台基于网络的非线性编辑系统的设计与实现

针对地市级电视台的业务特点和需求,设计了基于网络的非线性编辑系统,并对系统工作流程、方案设计、拓扑结构、网络性能、系统管理要求进行了分析,提出了具体实现方法.     

多排数翅片管空冷器风阻特性的数值模拟

本文对多排数翅片管空冷器空气侧的风阻特性进行了数值模拟.利用商用软件Fluent进行数值计算,结合经验公式和已有的实验数据,分析了不同入口风速下,阻力的变化规律以及流动阻力和温度变化对模拟计算的影响.     

非线性编辑实验室的构建与实验教学

以计算机为操作平台的非线性编辑系统广泛应用于电视节目的制作 ,学校相关专业开设非线性编辑课程也需要配置非线性编辑系统作为学生实验用机。主要介绍一种学生实验用非线性编辑系统及实验室的配置方案以及该非线性编辑系统在实验教学中的性能特征。     

基于Java RMI技术的大型机群监控系统的设计与实现

机群监控系统可有效的提高大型机群的可管理性和可用性。本文提出了一种基于JAVA RMI技术的机群监控系统模型，并给出其实现方法。该系统具有开发快速、可跨平台、易于扩展等特性。     

On inversive maximal period polynomials over finite fields

Over finite field GF(q) withq a power of an odd primep, we characterize inversive maximal period polynomials in terms of polynomials of orderq + 1, and then we study some properties of polynomials of orderq + 1.This paper was written while the author was visiting the Institute of Information Processing, Austrian Academy of Sciences, AustriaThe author would like to thank the Institute of Information Processing, Austrian Academy of Sciences, Austria, for its hospitality and for using its facilities     

An integrated modelling environment for the embodiment of mechanical systems

The efficient, economical and often elegant transformation from a design schema to an embodied design solution containing real components is essential for the commercial success of a product. More often the ability of the designer to explore an optimum solution is severely frustrated by the analytically intensive and time-consuming aspects of embodying a concept. This paper presents a computer based system-modelling tool that is to be used by designers during the transformation of a concept to an embodied solution particularly to deal with standard components. This environment provides for the representation of conceptual schemas and subsequent embodiment from computer based component selection modules. These selection modules encompass the full range of electronic representations for standard mechanical components. The strategy for representing a mechanical system, its included components and their associated representations is discussed. The process of constructing a system model, specifying the desired performance characteristics and system resolution are also described.     

非方程灰色系统方法在长期水文预报中的应用初探

基于水文过程的复杂性和影响因子信息收集不完善这一基本事实，本文将流域水文系统视为含有灰元和灰信息的灰色系统，并初步实践了非方程灰色预报方法在长期水文预报中的应用。方法在一定意义上脱离了传统的以方程为中心的预报模式，它既考虑预报因子对预报量的不同影响程度，又不过分强调预报量与预报因子的具体相关函数形式，为长期水文预报提供了一种新思路。文中列出了实例，效果令人满意。