Towards an Accurate Probabilistic Modeling and Statistical Analysis of Temporal Faults via Temporal Dynamic Fault-Trees (TDFTs)

Abstract

Fault tree (FT) is a standardized notation for representing relationships between a system's reliability and the faults and/or the events associated with it. However, the existing FT fault models are only capable of portraying permanent events in the system. This is a major hindrance since these models fail to reflect accurately the other classes of faults, such as soft-faults, which are often temporary events that usually disappear after the source of the interference is no longer present. This paper proposes a new fault tree modeling paradigm, to capture the impact of temporal events in systems, called temporal dynamic fault trees (TDFTs). TDFTs are utilized to model the characteristics and dependencies between different temporal events, soft-faults, and permanent faults. These features are integrated into the proposed probabilistic models of the temporal gates, which are modeled as priced-timed automata. This paper also proposes a new FT analysis methodology, based on statistical model checking, designed to circumvent the state-explosion problem that is inherent to other model-checking approaches. The proposed analysis is able to evaluate the impact of temporal faults in systems, as well as to estimate the reliability and availability of the system over extended periods of time. The experiments reported in this paper demonstrate the versatility and scalability of the proposed approach. For instance, the results display the impact that temporal events may have in a digital system. Our observations indicate that while regular soft-fault analyses tend to underestimate metrics such as system reliability, TDFT analysis shows remarkable consistency with radiation testing, with differences of under 2%, in the conducted analysis.

Modelling and Resolution of Dynamic Reliability Problems by the Coupling of Simulink and the Stochastic Hybrid Fault Tree Object Oriented (SHyFTOO) Library

“…DFTs kick-started the proliferation of other formalisms that has continued for two decades now. For instance, a recent research paper [35] proposed a new fault tree modeling paradigm named Temporal Dynamic Fault Trees (TDFT) that is able to calculate the reliability and availability of a system exploiting the notion of soft-faults, i.e., temporary events that disappear after the source of the interference is no longer present. Other contributions [36,37] integrated the primitives of parametric, Repairable Dynamic Fault Trees (RDFT), and introduced a new formalism called Generalized Fault Trees (GFT) with the aim of reducing the cost of analysis and enabling the evaluation of different repair policies.…”

A Hybrid Multilevel FTA-FMEA Method for a Flexible Manufacturing Cell Based on Meta-Action and TOPSIS

“…To analyze the dynamic system such as soft system, Kabir et al [13] extended a fault tree to a temporal fault tree (TFT). Ammar et al [14] also focused on the TFT and proposed a new FTA method that is based on statistical model checking to circumvent the state explosion problem. Joshi et al [15] proposed a prior robustness approach for the Bayesian implementation of the FTA and used in two real-life fields: a spacecraft re-entry and a control system.…”

Modeling the influence of short-term mode of component for non reserved system on its reliability

“…У [2] розглянуто підхід, який ґрунтується на використанні звичайних динамічних дерев відмов із подальшою побудовою на їх основі простору станів. У [3] використано для формалізації збоїв, складної поведінки за навантаженням та часом тимчасові оператори ("Gate"), які злучаються або пропускаються залежно від режиму роботи системи. Недоліками описаних вище підходів є те, що частину динамічних явищ, зокрема короткочасні режими роботи деяких елементів системи, не вдається адекватно описати використовуючи запропоновані модифікації дерев відмов.…”