Reliability models applicable to space telescope solar array assembly system

A complex system may consist of a number of subsystems with several components in series, parallel, or combination of both series and parallel. In order to predict how well the system will perform, it is necessary to know the reliabilities of the subsystems and the reliability of the whole system. The objective of the present study is to develop mathematical models of the reliability which are applicable to complex systems. The models are determined by assuming k failures out of n components in a subsystem. By taking k = 1 and k = n, these models reduce to parallel and series models; hence, the models can be specialized to parallel, series combination systems. The models are developed by assuming the failure rates of the components as functions of time and as such, can be applied to processes with or without aging effects. The reliability models are further specialized to Space Telescope Solar Arrray (STSA) System. The STSA consists of 20 identical solar panel assemblies (SPA's). The reliabilities of the SPA's are determined by the reliabilities of solar cell strings, interconnects, and diodes. The estimates of the reliability of the system for one to five years are calculated by using the reliability estimates of solar cells and interconnects given n ESA documents. Aging effects in relation to breaks in interconnects are discussed

Methodology of Transportation System Management

In this paper, we propose an improved design methodology to meet the changing demands of an existing transport system available in rural or urban areas. This is necessary to focuses on the convenience and comfort for road users. Effective control of the overall transport system is essential to enhance the safety and convenience. However, onion changes in population coupled with the economic development, mean that most of the control and management methods can quickly become dated or even have been unsuitable, leading to the vehicle development. This paper thus seeks to develop a practical and efficient methodology to allow current transport system to be updated to alleviate congestion. For this purpose we undertake a comparison between internal transport system and urban traffic. The methodology useful for many applications which are necessary for development in current transport system