A method of estimating the standard gibbs free energy of formation

Standard Gibbs free energy of formation (ΔG_f⁰), an important property needed in design calculations has been estimated using molar refraction, R_M. The linear relationships derived between ΔG_f⁰ and R_M tested with the data on 8 series of hydrocarbons at 228 compounds yielded average deviations comparable to the methods cited in recent literature. The method can be used as an alternative to the existing ones, because of its simplicity combined with reasonable accuracy.     

智能温湿度测控仪

本文提出一种利用MCS-51系列单片机实现温湿度自动检测和控制的智能仪表,文中对仪器的工作原理、硬件组成和软件设计作了较为详细的介绍。     

大型软件缺陷修正跨国外包后的质量控制

研究了大型软件A93K SOC Series 93000缺陷修正在跨国外包后的质量控制问题,提出了采用缺陷跟踪和缺陷检查的解决方案;并通 过缺陷修正数量和工作流服务质量等指标的分析,论证了CRT(Customer Response Team)质量控制的有效性;得到了综合评价缺陷修正质量控 制成效的一个重要技术指标,即缺陷修正比率FROC(Fixing Rate of CR)。     

网络虚拟服务器安全性对策研究方案

针对目前虚拟服务器的安全问题进行研究。设计了一种新的Web虚拟服务器应用安全的解决方案,在代码一级对其攻击进行检测和防护。即一方面,确定代码位置,利用特定的API调用在其前后对用户输入相关的参数进行判断是否含有可能的攻击存在并进行相应的处理;另一方面在应用源代码或中间代码文件中插入本方案的检测代码,以实现防护的功能。     

一种脉冲氦离子化检测器气相色谱仪计量性能的校准方法

对脉冲氦离子化检测器(Pulsed Discharge Helium Ionization Detector,PDHID)的校准是确保微量气体分析数据准确性的重要保证。针对微量气体PDHID校准方法难点问题,采用实验设计方法,选择合适标准物质与色谱条件进行试验。实验结果表明:氢气等气体可作为标准物质,该校准方法检测限:DPDHID<2.5<10-12g/s,扩展不确定度:U rel<5%,k=2,可开展对PDHID的校准。     

可转位刀片三维断屑槽CAT/CAD/CAM系统

给出了一个可转位刀片三维断屑槽测量、设计与制造的CAT／CAD／CAM系统，并对该开发系统各部分结构和功能进行了简介。     

固定脉宽频率的自动化测试系统研究

论文的目的是实现电压频率转换电路的自动化测试。介绍了测频方法的原理和与计数法的比较,测试系统的软硬件组成和实现方法,并对实现的结果进行了说明。     

电池管理系统在奥运纯电动大巴中的设计研究

本文以北京2008奥运纯电动大巴的运营为背景,重点介绍了电动大巴上车载电池管理系统的工作特点以及硬件部分的设计理念,并完成了系统各部分之间的通讯设计,最终实现了对电动大巴各种工作状况的检测与控制。     

列车折关检测系统分析及数据处理算法研究

折角塞门非正常关闭问题至今仍是列车制动系统中一个未完全解决的难题.文章介绍了列车折关检测系统原理,分析了检测系统中的主要功能模块;针对检测数据处理的关键技术,给出了相应解决算法,实验表明处理算法理想有效.     

Effective-capacity-based stochastic delay guarantees for systems with time-varying servers, with an application to IEEE 802.11 WLANs

Many network applications rely on stochastic QoS guarantees. With respect to loss-related performance, the effective bandwidth/capacity theory has proved useful for calculating loss probabilities in queues with complex input and server processes and for formulating simple admission control tests to ensure associated QoS guarantees. This success has motivated the application of the theory for delay-related QoS too. However, up until now this application has been justified only heuristically for queues with variable service rate. The paper fills this gap by establishing rigorously that the effective bandwidth/capacity theory may be used for the asymptotically correct calculation and enforcement of delay tail-probabilities in systems with variable rate servers too. Subsequently, the paper applies the general results to IEEE 802.11 WLANs, by representing each IEEE 802.11 station as an On/Off server and employing the effective capacity function for this model. Comparison of analytical results with simulation validates the effectiveness of the On/Off IEEE 802.11 model for delay-related QoS, complementing earlier results on loss-related performance.