A study on how to define a structure function of a multi-state system

2015 Fiscal Year Final Research Report

• Project/Area Number: 25350441
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social systems engineering/Safety system
• Research Institution: Nagoya Institute of Technology
• Principal Investigator: Ohi Fumio 名古屋工業大学, 工学(系)研究科(研究院), 教授 (60116001)
• Co-Investigator(Kenkyū-buntansha): Nakade Koichi 名古屋工業大学, 大学院工学研究科, 教授 (50207825)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 多状態信頼性システム / 半順序状態空間 / モジュール分解 / 確率的信頼性評価方法 / FTA / 複数部品の最適取り替え政策 / ネットワーク信頼性 / フラクタル的データ解析手法

Outline of Final Research Achievements

For a multi-state system with partially ordered state spaces, we have shown (1)stochastic evaluation methods of performance of the system by a modular decomposition and a decomposition of the structure function into a family of series systems, (2)how to determine the structure function by FTA method, (3)examinations of importance measures in a context of complex network theory, which relates the reliability theory to the complex network theory with understanding the partially ordered state spaces to be networks via Hasse diagram. For a maintenance problem of a multi-state and multi-unit system, a structure of the optimal maintenance policy is explained to be control-limit type by Markovian decision process method.
A fractal analysis method of time series data, called Higuchi method, is mathematically showed to have a relation with the box-counting dimension. We also proposed a new analysis method and showed it to work efficiently in practical situations.

Free Research Field

信頼性理論