臺灣博碩士論文加值系統

此論文研究分析兩種具有偵測延遲的系統，而每台機器故障時間和修復時間分別服從指數分配和一般分配，偵測延遲的時間服從指數分配。利用遞迴方法與輔助變數技巧，針對兩種不同的系統，推導出穩態模式下的效益性( )，對於每個系統，我們分別導出三種不同的修理時間分配(如：指數分配，k-stage Erlang分配，deterministic分配)，最後，我們用電腦軟體來比較不同修理分配下的效益，並比較其效益之大小。

   We study two availability models with fault detection delay. The time-to-failure and time-to-repair of the active units are assumed to be exponentially and generally distributed, respectively. The detection delay are assumed to be exponentially distributed. We present a recursive method, using the supplementary variable technique and treating the supplementary variable as the remaining repair time, to develop the steady-state availability, (or ), for two availability models. For each availability model, the explicit expressions for the for three various repair time distributions, such as exponential, k-stage Erlang, and deterministic are provided. Finally, the computer software is utilized to calculate the availability of two models. Comparisons are performed for three different repair time distributions.

Contents1. Introduction ………………………………………………………1  1.1 Literature Review ……………………………………………1  1.2 The Scope of the Study………………………………………22. Problem Statement…………………………………………………4  2.1 Notation and Probabilities…………………………………43. Availability Analysis of Two Models…………………………6  3.1 Availability Model 1…………………………………………6    3.1.1 Special cases ……………………………………………9  3.2 Availability Model 2 ………………………………………11    3.2.1 Special cases……………………………………………154. Comparison of Two Availability Models ……………………17  4.1 Comparison of the downtime between two models………17  4.2 Comparison of the improved downtime rate for two      models …………………………………………………………245. Conclusions and Future Research ……………………………26  5.1 Conclusions……………………………………………………26  5.2 Future Research………………………………………………26Reference………………………………………………………………27

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