Multiformalism and Transformation Inheritance for Dependability Analysis of Critical Systems

With the increasing demand for high availability in safety-critical systems such as banking systems, military systems, nuclear systems, aircraft systems to mention a few, reliability analysis of distributed software/hardware systems continue to be the focus of most researchers. The reliability analysis of a homogeneous distributed software/hardware system (HDSHS) with k-out-of-n : G configuration and no load-sharing nodes is analyzed. However, in practice the system load is shared among the working nodes in a distributed system. In this paper, the dependability analysis of a HDSHS with load-sharing nodes is presented. This distributed system has a load-sharing k-out-of-(n + m) : G configuration. A Markov model for HDSHS is developed. The failure time distribution of the hardware is represented by the accelerated failure time model. The software faults are detected during software testing and removed upon failure. The Jelinski–Moranda software reliability model is used. The maintenance personal can repair the system up on both software and hardware failure. The dependability measures such as reliability, availability and mean time to failure are obtained. The effect of load-sharing hosts on system hazard function and system reliability is presented. Furthermore, an availability comparison of our results and the results in the literature is presented.

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DEPENDABILITY ANALYSIS OF HYBRID REDUNDANCY SYSTEMS USING FUZZY APPROACH

International Journal of Reliability Quality and Safety Engineering ◽

10.1142/s0218539310003846 ◽

2010 ◽

Vol 17 (04) ◽

pp. 331-350 ◽

Cited By ~ 1

Author(s):

C. CHELLAPPAN ◽

G. VIJAYALAKSHMI

Keyword(s):

Markov Model ◽

Reliability Analysis ◽

Failure Rate ◽

Fuzzy Numbers ◽

Fault Tolerant ◽

High Reliability ◽

Model Parameters ◽

Critical Systems ◽

Dependability Analysis ◽

Modular Redundancy

With the increasing demand for high reliability in mission critical systems such as space shuttle, digital flight and real time control to mention a few, reliability analysis of fault tolerant systems continues to be the focus of most researchers. The reliability analysis of triple modular redundancy (TMR) and hybrid redundancy (TMR with spares) systems is in general carried out with the assumption of failure rate being precise. However, in practice failure rate is imprecise due to the uncertainties of system operation. In this paper, the dependability analysis of hybrid redundancy systems (HRS) comprising of N-modular redundancy (NMR) and standby redundancy is presented assuming failure rates and repair rates as fuzzy numbers. Each module of the NMR is assumed to have access to a number of cold spares and a repair facility. A Markov model for the HRS is developed. As the Markov model parameters may not be precisely known due to various reasons, vertex method and α-cut method is applied. These methods allow uncertainty-based parameters that are represented as fuzzy numbers. The dependability measures such as availability and reliability are obtained. A comparative study of the fuzzy results and the conventional results using probability concepts is presented.

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Dependability analysis of safety critical systems: Issues and challenges

Annals of Nuclear Energy ◽

10.1016/j.anucene.2018.05.027 ◽

2018 ◽

Vol 120 ◽

pp. 127-154 ◽

Cited By ~ 5

Author(s):

Raj kamal Kaur ◽

Babita Pandey ◽

Lalit Kumar Singh

Keyword(s):

Critical Systems ◽

Safety Critical ◽

Dependability Analysis ◽

Safety Critical Systems

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Variability management in safety-critical systems design and dependability analysis

Journal of Software Evolution and Process ◽

10.1002/smr.2202 ◽

2019 ◽

Vol 31 (8) ◽

pp. e2202 ◽

Cited By ~ 1

Author(s):

André Luiz de Oliveira ◽

Rosana Braga ◽

Paulo Masiero ◽

David Parker ◽

Yiannis Papadopoulos ◽

...

Keyword(s):

Systems Design ◽

Critical Systems ◽

Safety Critical ◽

Dependability Analysis ◽

Safety Critical Systems ◽

Variability Management

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Customization of Rational Unified Process (RUP) Methodology for Safety-Critical Systems

International Review on Computers and Software (IRECOS) ◽

10.15866/irecos.v11i6.9184 ◽

2016 ◽

Vol 11 (6) ◽

pp. 566

Author(s):

Mina Zaminkar ◽

Mohammad Reza Reshadinezhad

Keyword(s):

Critical Systems ◽

Safety Critical ◽

Unified Process ◽

Safety Critical Systems

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Formal Verification of Control System Software

10.23943/princeton/9780691181301.001.0001 ◽

2019 ◽

Author(s):

Pierre-Loïc Garoche

Keyword(s):

Control System ◽

Formal Verification ◽

Formal Analysis ◽

Critical Systems ◽

System Software ◽

Unified Approach ◽

Verification Methods ◽

Autonomous Cars ◽

Computer Scientists ◽

Verification Techniques

The verification of control system software is critical to a host of technologies and industries, from aeronautics and medical technology to the cars we drive. The failure of controller software can cost people their lives. This book provides control engineers and computer scientists with an introduction to the formal techniques for analyzing and verifying this important class of software. Too often, control engineers are unaware of the issues surrounding the verification of software, while computer scientists tend to be unfamiliar with the specificities of controller software. The book provides a unified approach that is geared to graduate students in both fields, covering formal verification methods as well as the design and verification of controllers. It presents a wealth of new verification techniques for performing exhaustive analysis of controller software. These include new means to compute nonlinear invariants, the use of convex optimization tools, and methods for dealing with numerical imprecisions such as floating point computations occurring in the analyzed software. As the autonomy of critical systems continues to increase—as evidenced by autonomous cars, drones, and satellites and landers—the numerical functions in these systems are growing ever more advanced. The techniques presented here are essential to support the formal analysis of the controller software being used in these new and emerging technologies.

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