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41.
Naoki Takinami Takashi Chino Shotaro Yoshida Isao Miura Kazuo Watanabe Kazuo Amano 《Electrical Engineering in Japan》1994,114(6):1-12
When ground-fault problems occur on a cable line, immediate fault location and restoration are required. Therefore, various new methods to locate the fault point instantaneously have been investigated to replace such conventional methods as the Murray loop method and the pulse radar method [1]. These methods require a long time to locate the fault point. One possible fault location method is to sense the temperature rise following a ground fault using a fiber optic distributed temperature sensor. Application of this method was found feasible through sensing the temperature rise at a ground-fault test using a thermocouple as a temperature sensor with test cables [4]. A power/optical composite cable was prepared experimentally and after verifying its thermal mechanical performance, the temperature rise at an incidence of a fault was determined and the anticipated performance was demonstrated in a ground-fault test. This article describes the outline of the test. 相似文献
42.
1 IntroductionWiththerapiddevelopmentofInternetandmobilecommunications,theresearchonwirelessmobilenetworkshasbecomethenewhotspotinin formationtechnologyfield .Asweknow ,mobileterminals (mobilephone,forexample)arethetooltohelppeopletoaccessanyinformationtheyneedbyanymediaatanytimeandanywhere .However,itissometimesdifficultformobileterminalstoplaysucharolebecauseofthelimitationssuchaslimitedca pacity ,lowpower,andinconvenienceinoperating .So,peoplehopetofindanotherwaytoaccessnet workinformatio… 相似文献
43.
针对目前应用在UNIX系统中入侵检测知识库适应能力不足的问题.提出了一种适应于不同系统环境的知识库体系结构。检测规则按相应系统与服务类型以模块化形式存储,通过应用配制文件加载。实现了入侵检测知识库的可扩展性.提高了入侵检测知识库的通用性,并且可以提高检测规则的搜索效率。 相似文献
44.
Yu. S. Yakovlev 《Cybernetics and Systems Analysis》2003,39(5):765-776
Distinctive features of architectural-structural organization and use of memory networks are considered with the aim of choosing an optimal configuration in designing distributed computer systems. 相似文献
45.
This paper presents the Navigation Maps Modeling approach (NMM), which provides platform independent models for characterizing navigation maps of web applications. The NMM approach is conceived to obtain a trade off between high and low-level design notations. As high-level design notations, NMM models permit architectural details that may hinder the overall understanding of the web application to be left out. As low-level design notations, NMM models can easily be transformed into detailed architectural designs, which are very valuable at coding and maintenance stages. 相似文献
46.
微型集散系统通用过程控制软件包 总被引:1,自引:0,他引:1
本文给出一种新的基于MCS-51单片机集散系统通用过程控制软件包的设计原理及其实施方法。文中重点地阐述了微型集散系统的构在民,通用过程控制软件的自动生成,主要数据结构与程序结构,实现方法及关键技术等。本软件包是采用TURBOC2.0版本和MCS-51泄编语言编程的,并通过了MCS-51组合软件的编译,形成了可用的目标码程序系统。 相似文献
47.
This paper presents the development of an event-driven control architecture and its implementation in a physical simulator of a computerized manufacturing system using object-oriented techniques. The architecture was developed to improve the efficiency of handling concurrent control events in the DOS environment. In the implementation, the control system of the physical simulator consists of four distinct layers of control devices: a PC/386 computer, a microcontroller, I/O modules and the system's control devices such as motors, solenoids and sensors. A control program residing in the PC/386 coordinates system-level tasks such as event scheduling, while a BASIC program running on the microcontroller handles all low-level control tasks such as sensor monitoring and motion control. The concepts and developments presented in this paper should help in implementing an efficient control system for both CIM systems and their physical simulators. 相似文献
48.
全金属反射光学系统结构的有限元分析 总被引:3,自引:1,他引:2
用有限元分析方法对全金属反射光学系统在各种受力状态下的变形、应力及固有频率做了全面的分析,并给出了结构多次优化后的分析结果。 相似文献
49.
针对近几年安阳市城区规模的不断扩大和安东新区的开发启动以及房地产市场的迅速发展,根据相关标准,结合安阳市城市发展的实际需要,提出了安阳市民用建筑有线电视管道工程设计及施工规范。 相似文献
50.
New small‐scale dispersed generation systems, such as fuel cells and micro gas turbines, have made remarkable advances lately and they will be applied practically in the near future. Although a large number of researches on the introduction of small‐scale dispersed generation systems have been carried out, only a small number of small‐scale dispersed generation systems are considered in these researches. Therefore, little is known about problems to be solved when a large number of small‐scale dispersed generation systems are introduced into electric power systems. This paper deals with a super‐distributed energy system that consists of a great number of dispersed generation systems such as fuel cells, micro gas turbines, and so on. The behavior of a customer with a dispersed generation system is simulated as the Ising model in statistical mechanics. The necessity of a distribution network in super‐distributed energy systems is discussed based on the Ising model. The feasibility of decentralized autonomous control using vicinity information is also investigated on the basis of stability analysis of the Hopfield neural network model. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(1): 43–55, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10368 相似文献