电厂热力系统耗差分析系统实现的研究与发展

总结了电厂热力系统耗差分析几种实现方式，回顾了国内在该领域的发展过程。电厂热力系统耗差分析实现方式分别经历了独立的耗差分析系统、基于DCS的耗差分析系统、基于MIS的耗差分析系统。并在不同的分析方式上进行了评价，指出了耗差分析系统的发展方向。     

Proactive resource allocation for asynchronous real-time distributed systems in the presence of processor failures

We present two proactive resource allocation algorithms, RBA^*-FT and OBA-FT, for fault-tolerant asynchronous real-time distributed systems. The algorithms consider an application model where task timeliness is specified by Jensen's benefit functions and the anticipated application workload during future time intervals is described by adaptation functions. In addition, we assume that reliability functions of processors are available a priori. Given these models, our objective is to maximize aggregate task benefit and minimize aggregate missed deadline ratio in the presence of processor failures. Since determining the optimal solution is computationally intractable, the algorithms heuristically compute sub-optimal resource allocations, but in polynomial time. Experimental results reveal that RBA^*-FT and OBA-FT outperform their non-fault-tolerant counterparts in the presence of processor failures. Furthermore, RBA^*-FT performs better than OBA-FT, although OBA-FT incurs better worst-case and amortized computational costs. Finally, we observe that both algorithms robustly withstand errors in the estimation of anticipated failures.     

本地缓存和代理服务器环境下的网络日志挖掘

介绍了网络日志挖掘的基本概念，提出了一个网络日志挖掘通用系统的结构，分析了本地缓存和代理服务器对日志挖掘的影响，并给出了一种近似解决方案。这种方案通过网络拓扑结构和日志文件记录的结合，将杂乱无章的日志记录组合成具有语义信息的事务记录，从而使挖掘结果更有意义。     

唐钢ER70S-6焊丝钢的生产工艺研究及质量分析

介绍了唐钢ER70S-6焊丝钢的特点，对盘条质量进行了分析。对该钢化学成分、冶炼和轧制工艺进行了优化研究，使其综合性能明显改善。     

基于Web平台的机器翻译系统

用户可以通过Internet访问和使用机器翻译系统，在线机器翻译系统可以帮助用户阅读网上外文材料。用户一般通过购买相关软件或访问提供在线翻译的网站来获取翻译服务，但是专用软件价格昂贵，或者获得的在线翻译效果不能令人满意。通过Web服务与J2EE技术的结合，提出了将机器翻译拳统包装为Web服务的机制，使企业和个人能够以较低的代价方便地享受更高质量的翻译服务。     

固定式宽带无线接入技术--LMDS

本地多点分配业务(LMDS)是近年来在国际上兴起的固定式宽带无线接入技术,具有传输容量大、起始费用低的优点,受到了国内外电信业务经营者的普遍关注.文章介绍了LMDS提供的业务类型、工作频率、系统结构和标准化情况,并将LMDS与有线电视网络、ADSL、MMDS等现有的接入技术进行了比较.文章认为LMDS的商业推广尚需解决信号质量、服务区尺寸、费用等制约因素.     

Quality-of-Service Based Protection in MPLS Control WDM Mesh Networks

Intelligent methods for automatic protection and restoration are critical in optical transport mesh networks. This paper discusses the problem of quality-of-service (QoS)-based protection in terms of the protection-switching time and availability for end-to-end lightpaths in a WDM mesh network. We analyze the backup lightpath-sharing problem in such networks and study the correlation of the working lightpaths and the impact of the correlation on the sharing of the backup lightpaths. We present a multi-protocol-label-switching (MPLS) control-based fully distributed algorithm to solve the protection problem. The proposed algorithm includes intelligent and automatic procedures to set up, take down, activate, restore, and manage backup lightpaths. It greatly reduces the required resources for protection by allowing the sharing of network resources by multiple backup lightpaths. At the same time, it guarantees, if possible, to satisfy the availability requirement even with resource sharing by taking the correlation of working lightpaths into consideration. A simple analysis of the proposed algorithm in terms of computation time and message complexity indicates that the implementation of the algorithm is practical. The illustrative studies that compare the performance of 1:1, unlimited sharing, and QoS-based backup sharing algorithms indicate that QoS-based sharing achieves comparable performance as unlimited sharing, which is much better than the 1:1 backup scheme in terms of connection blocking probability, average number of connections in the network for a given offered load, and network resource utilization.     

BYJ型防喷脱接器的设计与应用

本文介绍了BYJ型防喷脱接器的结构和工作原理。它既有抽油杆与大泵活塞脱接功能,又能实现不压井作业施工,是大型抽油泵理想的配套工具。现场应用表明,该防喷脱接器对接成功率较高,并实现了大泵井不压井施工。     

钨系延期药预点火反应机理研究

通过程控升温模拟点火条件，根据ＤＳＣ图谱分析，找出主要反应区的温度范围。研究结果表明，钨系延期药预点火反应是一个真正的固－固反应。     

Temperature and pressure effects on supercritical CO2 extraction of tomato seed oil

Tomato seed oil was extracted with supercritical carbon dioxide in a semibatch-flow extractor within the temperature range 313–343 K and the pressure range 10.8–24.5MPa. The extraction rates increased with pressure, but decreased with temperature increase because of the variation in solvent density and resultant differences in oil solubility. The fatty acid composition of the extracted oil was similar to that of soybean oil.