Combined centralized and decentralized fault diagnosis for discrete event systems

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Elektrik ve Elektronik Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2014

Öğrenci: RUHİ KARAV

Danışman: ŞENAN ECE SCHMİDT

Özet:

Discrete Event Systems (DES) are used for modeling systems such as manufacturing systems, telecommunication systems and transportation systems. It is possible to incorporate the fault model in the DES model together with a fault diagnosis approach to evaluate the robustness and the reliability of the system at the design stage. There are centralized or decentralized fault diagnosis approaches in the literature. The centralized fault diagnosis achieves stronger results however it does not scale to reasonably large systems because of its complexity. The decentralized diagnosis is applicable to real-life systems with a cost of possible misses of faults. This thesis proposes a combination of centralized and decentralized fault diagnosis for DES models. To this end, the thesis makes use of the observation that some parts of the faulty DES behavior might be detected by decentralized diagnosis while other parts need a centralized diagnoser. Hence, the overall complexity of the diagnosis is reduced while maintaining the ability to detect all faults. The thesis proposes a systematic diagnosis approach together with the algorithms and practical applications to manufacturing system and communication network examples.