户式中央空调的节能研究

对户式中央空调系统节能问题作了研究,从住宅建筑空调负荷的计算特点和方法、系统主机容量的确定、末端设备的选择到系统调节特性等诸多方面,综合考虑,并结合实际工程,阐述了影响户式中央空调能量消耗的各种主要因素和改进措施.     

计算机网络安全系统设计

分析了现代计算机网络所面临的威胁和各种安全问题,同时提出了在设计一个有关网络系统时应该考虑的一些安全问题,如网络安全策略与技术、网络的访问控制、网络数据加密技术、信息隐藏技术等安全问题。     

浅析FIPS PUB 140-2标准

论文简单分析了FIPSPUB140-2标准及其在密码模块开发过程中的指导意义,可作为密码模块技术开发人员在进行安全性设计时的参考。     

生存能力技术及其实现案例研究

生存能力技术谋求增强系统在面临攻击、失效等灾难情况下仍能继续提供服务的能力。本文提出了以多样化分布式动态备份技术和主动漂移机制为手段，以被保护目标的机动性和隐蔽性为目的的生存能力技术模型。提出了多样化体系理论及其实现案例，基于该理论设计并实现了自适应TOM方法。最后通过模拟和测试探讨了生存能力的评价方法，并验证了本文的结果。     

有线电视宽带网边界路由系统安全技术研究

提出在当今有线电视宽带网络环境下,从构建安全的边界路由系统出发,研究在边界路由器上采取针对有线电视宽带网内部网络的报文过滤和针对路由系统本身的安全策略,并在某有线电视宽带网络中进行了典型应用,实践证明可以达到事半功倍的网络安全目的.     

Analysis of spontaneous electrochemical oscillations by energy distribution technique

Analysis of non-stationary electrochemical oscillations emerges utilization of the techniques allowing an observation of time evolution of their parameters such as instantaneous frequency, amplitude or frequency band. An algorithm of extraction of these parameters can be based on one of linear or quadratic time-frequency representations of oscillations record. In this paper, the authors present representatives of such transformations (Choi-Williams and Cone-shaped) originating from one of the most popular joint time-frequency energy distribution—Wigner-Ville distribution. Short introduction to the mathematics of the topic discussed is provided, then the authors present an example of application in the analysis of current oscillations of copper dissolution process.     

计算机网络安全与防火墙技术

随着信息技术的高速发展和网络信息量的飞速膨胀，同时应有的安全防范措施相对薄弱，因此，非法入侵、对数据进行篡改和窃听等事件时有发生。本文就保证信息安全阐述了网络安全的必要性，论述了网络防火墙安全技术的功能、主要技术、配置、安全措施和防火墙设计思路等。     

The hydrogen economy, fuel cells, and electric cars

Hopes have again been raised about developing a “hydrogen economy”, in which hydrogen could be expected to replace oil and natural gas for most uses, including transportation and heating. It is again being claimed that hydrogen will be a widely available, clean, safe fuel. This article argues that such expectations are almost certainly illusory. Hydrogen, like electricity, is not an energy resource but an energy carrier. It takes more energy to extract hydrogen from water than burning the hydrogen can ever provide. There are also inevitable losses in storage, transmission, and final mechanical or heating applications. The question then turns on the efficiency—and safety—of the entire chain of conversion, from the energy source (fossil, solar, or other) to the final use. Moreover, energy sources (preferably renewable, for the long term) can be used for the direct creation of electricity, which can be introduced into the existing grid without requiring a vast investment in a new hydrogen distribution system. In addition, a hydrogen-based system would be unacceptably dangerous. This report will present a detailed technical and economic analysis of the problems with the proposed hydrogen economy and the advantages of some alternatives, principally electricity-based. A hypothetical case of what would be required for a hydrogen filling station serving the general public is closely examined.     

Efficiency improvements in US office equipment: Expected policy impacts and uncertainties

We create a business as usual scenario for office equipment electricity use from industry forecasts of equipment sales, surveys of equipment densities by building type, measured data on wattage and usage by equipment type and projected lifetimes for equipment. We then calculate electricity used by building type and equipment type for Energy Star and advanced scenarios and explore the sensitivity of these results to variations in key input parameters. According to our analysis, the Energy Star programme will save the US almost US$1 billion annually starting in the year 2000, with minimal expenditure of public funds.     

无线局域网安全问题研究

为了提供相当于有线局域网的数据安全,IEEE802.11定义了有线等价保密(WEP)协议。然而,最近的研究发现WEP存在严重的缺陷。介绍了无线局域网存在的安全隐患,分析了WEP的结构以及WEP协议的缺陷以及可能遭受的攻击,并探讨了改进方案。