Reliability analysis of multi-state system with application of multiple-valued logic

2017 ◽  
Vol 34 (6) ◽  
pp. 862-878 ◽  
Author(s):  
Elena Zaitseva ◽  
Vitaly Levashenko

Purpose The purpose of this paper is to develop a new mathematical method for the reliability analysis and evaluation of multi-state system (MSS) reliability that agrees with specifics of such system. It is possible based on the application of multiple-valued logic (MVL) that is a natural extension of Boolean algebra used in reliability analysis. Design/methodology/approach Similar to Boolean algebra, MVL is used for the constriction of the structure function of the investigated system. The interpretation of the structure function of the MSS in terms of MVL allows using mathematical methods and approaches of this logic for the analysis of the structure function. Findings The logical differential calculus is one of mathematical approaches in MVL. The authors develop new method for MSS reliability analysis based on logical differential calculus, in particular direct partial logical derivatives, for the investigation of critical system states (CSSs). The proposed method allows providing the qualitative and quantitative analyses of MSS: the CSS can be defined for all possible changes of any system component or group of components, and probabilities of this state can also be calculated. Originality/value The proposed method permits representing the MSS in the form of a structure function that is interpreted as MVL function and provides the system analyses without special transformation into Boolean interpretation and with acceptable computational complexity.

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mohammad Reza Pourhassan ◽  
Sadigh Raissi ◽  
Arash Apornak

PurposeIn some environments, the failure rate of a system depends not only on time but also on the system condition, such as vibrational level, efficiency and the number of random shocks, each of which causes failure. In this situation, systems can keep working, though they fail gradually. So, the purpose of this paper is modeling multi-state system reliability analysis in capacitor bank under fatal and nonfatal shocks by a simulation approach.Design/methodology/approachIn some situations, there may be several levels of failure where the system performance diminishes gradually. However, if the level of failure is beyond a certain threshold, the system may stop working. Transition from one faulty stage to the next can lead the system to more rapid degradation. Thus, in failure analysis, the authors need to consider the transition rate from these stages in order to model the failure process.FindingsThis study aims to perform multi-state system reliability analysis in energy storage facilities of SAIPA Corporation. This is performed to extract a predictive model for failure behavior as well as to analyze the effect of shocks on deterioration. The results indicate that the reliability of the system improved by 6%.Originality/valueThe results of this study can provide more confidence for critical system designers who are engaged on the proper system performance beyond economic design.


Author(s):  
Kailash Kapur ◽  
Elena Zaitseva ◽  
Vitaly Levashenko

The reliability of multi-state system is analyzed in this paper. In a multi-state system, both the system and its components may experience more than two reliability states. We propose dynamic reliability indices for reliability analysis of this system. Mathematical tools of the multiple-valued logic (the Logical Differential Calculus in particular) are exploited for definition of these indices. These indices estimate the effect on the multi-state system reliability by the state of a system component. We concentrate on series and parallel systems, because these structures are basic for many technical systems and get measures of reliability for the failure and restoration of these systems.


2008 ◽  
Vol 4 (1) ◽  
pp. 353-361
Author(s):  
Zaitseva Elena ◽  
Levashenko Vitaly ◽  
Matiaško Karol

Decomposition and Estimation of Multi-State Systems by Dynamic Reliability IndicesSome typical configurations of Multi-State System and their mathematical descriptions are considered in paper with relation to Reliability Analysis. Multiple-Valued Logic is applied for these descriptions synthesis and Dynamic Reliability Indices are used for Multi-State System reliability estimation. We concentrate on series and parallel systems, because these structures are basic for most of the technical system. We get measures of reliability for the failure and restoration of this system.


Author(s):  
Ali Muhammad Ali Rushdi

Symmetric switching functions (SSFs) play a prominent role in the reliability analysis of a binary k-out-of-n: G system, which is a dichotomous system that is successful if and only if at least k out of its n components are successful. The aim of this paper is to extend the utility of SSFs to the reliability analysis of a multi-state k-out-of-n: G system, which is a multi-state system whose multi-valued success is greater than or equal to a certain value j (lying between 1 (the lowest output level) and M (the highest output level)) whenever at least km components are in state m or above for all m such that 1 ≤ m ≤ j. This paper is devoted to the analysis of non-repairable multi-state k-out-of-n: G systems with independent non-identical components. The paper utilizes algebraic techniques of multiple-valued logic (together with known properties of SSFs) to evaluate each of the multiple levels of the system output as an individual binary or propositional function of the system multi-valued inputs. The formula of each of these levels is then written as a probability–ready expression, thereby allowing its immediate conversion, on a one-to-one basis, into a probability or expected value. The symbolic reliability analysis of a commodity-supply system (which serves as a standard gold example of a multi-state k-out-of-n: G system) is completed successfully herein, yielding results that have been checked symbolically, and also were shown to agree numerically with those obtained earlier.


2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Rajkumar Bhimgonda Patil ◽  
Suyog Subhash Patil ◽  
Gajanand Gupta ◽  
Anand K. Bewoor

PurposeThe purpose of this paper is to carry out a reliability analysis of a mechanical system considering the degraded states to get a proper understanding of system behavior and its propagation towards complete failure.Design/methodology/approachThe reliability analysis of computerized numerical control machine tools (CNCMTs) using a multi-state system (MSS) approach that considers various degraded states rather than a binary approach is carried out. The failures of the CNCMT are classified into five states: one fully operational state, three degraded states and one failed state.FindingsThe analysis of failure data collected from the field and tests conducted in the laboratory provided detailed understandings about the quality of the material and its failure behavior used in designing and the capability of the manufacturing system. The present work identified that Class II (major failure) is critical from a maintainability perspective whereas Class III (moderate failure) and Class IV (minor failure) are critical from a reliability perspective.Research limitations/implicationsThis research applies to reliability data analysis of systems that consider various degraded states.Practical implicationsMSS reliability analysis approach will help to identify various degraded states of the system that affect the performance and productivity and also to improve system reliability, availability and performance.Social implicationsIndustrial system designers recognized that reliability and maintainability is a critical design attribute. Reliability studies using the binary state approach are insufficient and incorrect for the systems with degraded failures states, and such analysis can give incorrect results, and increase the cost. The proposed MSS approach is more suitable for complex systems such as CNCMT rather than the binary-state system approach.Originality/valueThis paper presents a generalized framework MSS's failure and repair data analysis has been developed and applied to a CNCMT.


Author(s):  
Bingfeng Zhao ◽  
Liyang Xie ◽  
Yu Zhang ◽  
Jungang Ren ◽  
Xin Bai ◽  
...  

As the power source of an aircraft, aero-engine tends to meet many rigorous requirements for high thrust-weight ratio and reliability with the continuous improvement of aero-engine performance. In this paper, based on the order statistics and stochastic process theory, an improved dynamic load-strength interference (LSI) model was proposed for the reliability analysis of aero-engine rotor blade system, with strength degradation and catastrophic failure involved. In presented model, the “unconventional active” characteristic of rotor blade system, changeable functioning relationships and system-component configurations, was fully considered, which is necessary for both theoretical analysis and engineering application. In addition, to reduce the computation cost, a simplified form of the improved LSI model was also built for convenience of engineering application. To verify the effectiveness of the improved model, reliability of turbojet 7 engine rotor blade system was calculated by the improved LSI model based on the results of static finite element analysis. Compared with the traditional LSI model, the result showed that there were significant differences between the calculation results of the two models, in which the improved model was more appropriate to the practical condition.


mBio ◽  
2014 ◽  
Vol 5 (3) ◽  
Author(s):  
Christopher W. Lennon ◽  
Kimberly C. Lemmer ◽  
Jessica L. Irons ◽  
Max I. Sellman ◽  
Timothy J. Donohue ◽  
...  

ABSTRACTDksA is a global regulatory protein that, together with the alarmone ppGpp, is required for the “stringent response” to nutrient starvation in the gammaproteobacteriumEscherichia coliand for more moderate shifts between growth conditions. DksA modulates the expression of hundreds of genes, directly or indirectly. Mutants lacking a DksA homolog exhibit pleiotropic phenotypes in other gammaproteobacteria as well. Here we analyzed the DksA homolog RSP2654 in the more distantly relatedRhodobacter sphaeroides, an alphaproteobacterium. RSP2654 is 42% identical and similar in length toE. coliDksA but lacks the Zn finger motif of theE. coliDksA globular domain. Deletion of the RSP2654 gene results in defects in photosynthetic growth, impaired utilization of amino acids, and an increase in fatty acid content. RSP2654 complements the growth and regulatory defects of anE. colistrain lacking thedksAgene and modulates transcriptionin vitrowithE. coliRNA polymerase (RNAP) similarly toE. coliDksA. RSP2654 reduces RNAP-promoter complex stabilityin vitrowith RNAPs fromE. coliorR. sphaeroides, alone and synergistically with ppGpp, suggesting that even though it has limited sequence identity toE. coliDksA (DksAEc), it functions in a mechanistically similar manner. We therefore designate the RSP2654 protein DksARsp. Our work suggests that DksARsphas distinct and important physiological roles in alphaproteobacteria and will be useful for understanding structure-function relationships in DksA and the mechanism of synergy between DksA and ppGpp.IMPORTANCEThe role of DksA has been analyzed primarily in the gammaproteobacteria, in which it is best understood for its role in control of the synthesis of the translation apparatus and amino acid biosynthesis. Our work suggests that DksA plays distinct and important physiological roles in alphaproteobacteria, including the control of photosynthesis inRhodobacter sphaeroides. The study of DksARsp, should be useful for understanding structure-function relationships in the protein, including those that play a role in the little-understood synergy between DksA and ppGpp.


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