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81.
有线电视电缆网采用供电器进行集中供电,要计算一个额定容量的供电器可供放大器的最大级数,算式是很复杂的,而用VisaulFOXPRO6.0编写一个小程序,利用电脑对上述问题进行处理,就变得简单易用。 相似文献
82.
陈基禄 《华北电力大学学报(自然科学版)》1994,(4)
程控交换机是通信网的关键部分,其可靠性直接影响通信的安全性与有效性。本文对程控交换机实用产品的可靠性设计措施,如主控板双机备份、数据传输校验及程序复执等进行了论述,并提出了一些实用的具体方法。对用后台处理机进行话务信息处理作了基本介绍。 相似文献
83.
Jamshid Mohammadi 《Structural Safety》1985,2(4):301-308
Lifeline systems are vulnerable to two types of hazards arising from potential earthquake sources. These are the hazard of a fault-rupture strike on elements of a lifeline system and the hazard of overstress induced in different elements of the system because of the ground vibration. An optimum design method is presented in this paper for the design of a lifeline system for a maximum accepted probability of failure because of any of the two modes of failure. The method may be used to determine an optimum path between a number of fixed points which represent supply or demand stations in the system. 相似文献
84.
Florsheim Paul; Behling Steven; South Mikle; Fowles Timothy R.; DeWitt John 《Canadian Metallurgical Quarterly》2004,1(2):126
This study adopted a systemic approach to studying intervention efforts with delinquent youth, examining the association between several youth corrections programs and adult criminal outcomes. Two studies were designed to use juvenile and adult court records to evaluate the effectiveness of treatment programs provided to delinquent youth in state custody. The results of Study 1 suggested that court-recorded delinquent charges can be used to estimate delinquency severity. The results of Study 2 presented a discouraging but not entirely unexpected illustration of the effectiveness of intervention efforts among delinquent youth. It was found that time spent in juvenile detention facilities, work programs, and group homes was associated with negative adult criminal outcomes. No links between time spent in youth corrections programs and positive outcomes were identified. Implications for future program evaluation efforts are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
图书馆网站设计的探讨 总被引:8,自引:0,他引:8
介绍了当今信息时代建设图书馆网站的重要性和作用 ,以及在网站设计评估中应着重注意的包括网站内容、页面设计及安全性能等三方面的问题 ,同时提出 ,图书馆网站建设中如何在这几方面进行改进和完善。 相似文献
86.
In the framework of the European research project PV2GO, a new AC-module inverter was developed, taking into account all relevant aspects from a European market's point of view (standards, market, application, and research and development goals). The project goal was to achieve the overall system costs of 3 Euro per Wp for a modular plug-and-play photovoltaic system. For the photovoltaic-module, a standard 130-Wp Eurosolare module was chosen. The research and development (R&D) goal was to develop an advanced DC-control system consisting of a state-of-the-art programmable digital device and an Application Specific Integrated Circuit (ASIC) for the AC-control of the inverter. According to the topology concept, thermal and magnetic designs were optimized with regard to production technology and packaging for large-scale production. The new AC-modules were tested in a number of field-test sites in various parts of Europe and their reliability was assessed through Highly Accelerated Stress Tests. Efficiency and power quality have been tested in the laboratory. Further in the PV2GO project an optimization study of the manufacturing process of the new generation of AC-modules for high volume output was done. Another task was the pre-certification procedure to assure compliance with the European guidelines and standards. 相似文献
87.
88.
��������������˲��������̽�� 总被引:1,自引:1,他引:0
四川目前生产的天然气中含硫天然气占71%,而含硫天然气对高强度钻杆会产生硫化物应力腐蚀玻裂,因此,在含硫气井进行钻杆测试时,应重视钻杆的安全问题。文章探讨了高强度钻杆硫化物应力腐蚀玻裂的机理和影响钻杆脆断时间的各种因素,并提出在一定的条件下,高强度钻杆在含硫气并中进行测试是安全的。采用向钻杆内加缓蚀剂或内涂层钻杆,防硫油管测试,钻杆测试更加安全。建议继续开展高强度钻杆硫化物应力腐蚀玻裂时间的试验研究,以确定合理的钻杆测试安全时间。 相似文献
89.
The philosophy behind quality, environmental, and safety (QES) management systems is a concept that has been accepted by various contractors. Furthermore, a process has been developed insuring that the output produced conforms to customer satisfaction without violating any environmental, health, and safety rules and regulations. An effective QES program not only assures a quality product but also reduces costs, and enhances productivity. It is a top down process, i.e., top management together with line management and other employees develop the program and motivate all personnel to accept the process. Important functions to take under consideration are (1) explain and clarify the quality, environmental, and safety performance expected; (2) involve employees in decision-making and problem solving; (3) describe the consequences of poor quality and unsafe/unhealthy work conditions; (4) establish QES goals and provide feedback on performance; (5) provide a self-monitoring system; and (6) recognize and reinforce good performance and develop a reward system. This paper presents a discussion of the development of a portion of a QES management system which has been employed by a medium to large size construction company. In particular, Items 1–4, listed above, are described in detail. 相似文献
90.