Reliability of a laser communication system

Reliability function of a laser communication system is found with the help of a probability of error bound. Attention is restricted to the special case when the average photon arrivals at the receiver of the communication system is large. This reliability function is a complicated function and depends on number of parameters such as average number of signal photons, average number of noise photons, information rate and the channel capacity. The system reliability function and the corresponding curves can give the idea of system parameters which may be useful for the implementation of an optimum laser communication system.     

Reliability survival equivalence

The concept of reliability equivalence is extended to the case when the survival function is used as performance measure of a reliability system. Reliability equivalence factors are calculated for a single component and for two component series and parallel systems. These factors are solutions to transcendent equations which are solved and the solutions graphed with Mathematica.     

A Probability Method for Determining the Reliability of Electric Power Systems

Reliability measures how well a system can be expected to perform its intended purpose; it is expressed as a probability function with time and environment as variables. This paper discusses the mechanics of component failure and repair and shows that power system behavior follows a Markov process. The reliability of simple system configurations is evaluated analytically by solving the Markov equations. The reliability of complex systems is more easily evaluated by the use of digital computer simulation. The simulation method is described.     

Component Reliability Importance assessment on complex systems using Credible Improvement Potential

Nowadays system reliability performance represents a key issue and being reliable becomes a fundamental requirement of products in many manufacturing fields. The paper is focused on the reliability improvement of fault tolerant complex systems using component Reliability Importance (RI) procedures in order to assess the impact of each component on the overall system reliability. This study is focused on RI assessment during design stage with the aim of optimizing engineers' efforts and focusing on components with the greatest effect on the whole system. The first part of the paper focuses on a particular Reliability Importance measure, the Credible Improvement Potential (CIP), which is the most suitable RI metric for our purpose. The Reliability Importance assessment on a dedicated case study based on fault tolerant complex system is then proposed and results are discussed in detail.     

Reliability of a 3-unit cold redundant system with Weibull failure

Redundancy technique is applied to increase the reliability of a system where maintenance or repair is either not possible or is too costly. Reliability of a cold redundant system is always higher than a hot one. Moreover the increase in reliability due to adding of a unit in sequence can always be exactly determined.Literature is full of derivation of reliability expressions of a cold redundant system whose units obey exponential failure density. Due to extreme difficulty in evaluation of integrals involving Weibull density function, few attempts on derivation of reliability of redundant systems have been made. We have here derived reliability of a simple case of a 3-unit cold standby system whose units obey Weibull failure density.     

软件体系结构可靠性分析

软件体系结构可靠性评估是软件体系结构质量度量的重要内容之一,软件体系结构可靠性模型的研究是解决软件体系结构可靠性评估技术研究的重点。从软件体系结构的风格出发,依据马尔可夫随机过程理论,讨论了几种体系结构风格的可靠性模型,并说明可靠性模型的应用。软件体系结构可靠性评价在软件系统的设计初期进行实施,可以在设计的较早阶段发现系统中存在的问题,有利于改善系统性能,节约系统开发成本。     

Reliability analysis of the naphtha fuel oil system in a thermal power plant

The paper discusses the performance and reliability analysis of the naptha fuel oil system in a thermal power plant. Reliability, the availability function (A_v) and the mean time to system failure (MTSF) of this system have been calculated. An example follows, assuming various values of failure and repair rate.     

基于ML-II方法的k/n-系统Bayes可靠性评估

n中取k系统(简称k/n-系统)是工程实践中应用最广泛的系统类型之一。为了在系统现场试验样本量很小的情况下进行可靠性评估,首先利用次序统计量推导了k/n-系统寿命分布的密度函数,并给出了模型参数的第二类极大似然估计(ML-Ⅱ估计);然后给出了k/n-系统Bayes可靠性评估的一般步骤;仿真实例表明了方法的可行性。     

Customer-driven reliability models for multistate coherent systems

Reliability models for multistate coherent systems require customer interaction. The customer defines the distinctive component and system states. Knowing the component states, the authors estimate the probability distribution for each component. The customer specifies when a change in the state of any component forces a change in the state of the system. From this, the authors present a methodology to develop the customer's structure function and to calculate the probability of each system state. The customer defines and evaluates reliability. Using the customer's definition, one can summarize the probability distribution of the system     

便携式防空导弹武器系统可靠性分析与设计

可靠性是衡量武器系统性能的一项重要指标,也是影响系统效能的重要因素.在阐述可靠性及可靠性模型等基本概念的基础上,建立便携式防空导弹武器系统的可靠性模型,从可靠性设计的具体要求出发,结合便携式防空导弹武器系统组成及使用特点,提出了系统可靠性的量化评估模型和提高系统可靠性的设计方法,对提高便携式防空导弹武器系统可靠性和系统...     

公共广播系统主机的可靠性设计

公共广播系统的可靠性设计包括广播系统主机的可靠性、电源的可靠性、功放的可靠性、传输线路的可靠性等.通过实例描述了公共广播系统主机的可靠性设计.     

现代通信系统软件可靠性设计技术

可靠性设计是现代通信系统可靠性保证体系的关键环节。根据通信系统软件可靠性设计的一些经验，阐述了在软件开发过程中几种常用的、提高现代通信系统软件可靠性的设计方法，满足软件的可靠性要求。     

Reliability Growth Apportionment

A method is presented for apportioning reliability growth to the subsystems that make up a system in order to achieve the required reliability at least cost. Reliability growth apportionment is handled as an s-expected cost minimization problem subject to the constraint of meeting a system reliability requirement. The problem is formulated in terms of Duane's reliability growth model, and is solved using geometric programming. The method can be useful in the early stages of system design to determine subsystem reliability growth that will allow a system reliability requirement to be met, and in the latter stages of system design when reliability has fallen short of the required goal and improvements are necessary.     

系统可靠性模型综述

可靠性模型是指为预计或估算产品的可靠性所建立的可靠性框图和数学模型。介绍了几种系统可靠性模型及其相应的可靠性计算方法。     

有冷贮备单元的表决系统的可靠度分析

通过对有冷贮备单元的表决系统的可靠度分析,推导出其任务可靠度,计算出该系统的可靠寿命和平均失效前时间。有冷贮备单元的表决系统的可靠性模型应用于可靠度要求较高的有效载荷中。可以获得良好的效果。     

通信用VRLA蓄电池可靠性指标及计算探讨

在说明通信局（站）电源系统对VRLA蓄电池组可靠性要求的基础上，阐述了为了达到电信设备的电压、电流需求，通过串联或串并联构成电池组的单体VRLA蓄电池应达到的可靠性指标。在确定单体VRLA蓄电池应达到的可靠性指标。在确定单体VRLA蓄电池可靠性参数时，可通过现场使用调查或加速寿命试验的办法来求得。在单体VRLA蓄电池可靠性指标过低的情况下，可通过多种冗余连接方式来提高电池组的可靠性。     

Plastic encapsulated microcircuit reliability predicition: why?

Reliability prediction models for microcircuits have been a function of steady-state temperature. Failure rates generated from accelerated temperature tests were extrapolated to predict system reliability at system use temperatures. This is now known to be completely inaccurate. Attempts are now being made to predict the reliability of plastic encapsulated microcircuits (PEMs) based on accelerated temperature/humidity testing. Failure rates generated due to corrosion failure mechanisms at these high stress levels are then extrapolated and used to predict system reliability at used temperature/humidity conditions.This paper discusses the fallacy of this approach. A new concept for the assurance of PEM corrosion resistance is proposed. It will be shown that today's best commercial practice suppliers have already addressed the design, materials, and processing issues of molded packaged microcircuits, and corrosion is no longer a mechanism of concern to the user.     

State of Reliability Effort of the European Railways

Reliability, in the sense of safety and punctuality is a principal objective of railway management to keep ahead of competition. Reliability effort of European railways and the impact of modern methods for improving reliability is discussed. Further progress in this field depends on modern information systems and complex data processing. The proposed European data-processing system therefore and the already installed systems of several European railway authorities are introduced.     

会计电算化系统的内部控制研究

进入网络时代,企业内部控制的网络特征越发的明显,传统的会计工作方式也在发生着转变.会计电算化系统的应用,在很大程度上提升了财务管理的效率.会计电算化是应用现代信息技术和计算机技术代替人工进行会计的算账、记账、查账,从而提升会计工作的效率和质量.发展会计电算化对发挥会计职能、规范会计工作及提升会计工作的质量具有重大意义.会计电算化的发展,也对系统的内部控制提出了更高的要求.而会计电算化系统的内部控制方面仍然存在一些问题.因此,本文将对会计电算化系统的内部控制存在的问题及对策进行简要的分析及研究.     

Commercial-Components Initiative: Ground Benign Systems-plasticencapsulated microcircuits

The purpose of the Commercial Components Initiative-Ground Benign Systems was to determine if commercial off-the-shelf PEM (plastic-encapsulated microcircuits) are suitable for use in ground-benign, dynamically-fixed military electronic systems. If so, they could replace the more expensive components presently specified by DoD (US Dept. of Defense), resulting in appreciable life-cycle cost savings. At issue is whether the components produced for the commercial industry are reliable and durable enough to withstand the environments and life expectancies of military systems. Reliability was not formally proven. A more practical informal reliability test for this project, which DSD dubbed Run for Reliability, was to install the PCB in the system and let the operational hours accrue beyond the subsystem and Signal Processor lifetime allocations. The Run for Reliability shows promise that commercial hardware could be proven in a formal reliability demonstration test