Nupur Goyal

Automotive Water Cooling System Analysis Subject to Time Dependence and Failure Issues

In an automobile engine, the heat transfer cannot be possible without cooling system support. The cooling system has a great importance in the engines. It coolants overheat of the engine, and prevents it from breakdown, thats why a highly reliable cooling system is the necessity of every engine but there are many failure issues with a cooling system which are time dependent. This paper investigates the performance of a water cooling system with the consideration of their significant components by taking the attention of three types of time dependent failure issues while the water cooling system is maintained by the sufficient repair facility. It is obvious that in the lack of maintenance, failure issues in water cooling system lead with the increment of time. Maintenance and operating costs of water cooling system affect the economy of overall engine very much, so, it is necessary to be aware about overheating of engines during peak ambient conditions when it is operated with full capacity. Hence, a Mathematical model of water cooling system is proposed by using the Markov process and supplementary variable technique.

Gas Turbine Assimilation Under Copula-Coverage Approaches

Reliability assessment has a major step towards the development of fault-tolerant system. In different fields of engineering and physical/ailed sciences, researchers or engineers have several reliability approaches for the better performance of the mechanical system. In this research work, the authors focus on the study of reliability of gas turbine. An efficient and reliable gas turbine plays a major role in the power generation as a back-up power plant. In addition to the reliability, authors also determined the mean time to failure subject to the each failure rate. This chapter models a simple gas turbine and formulated with the Markov Process and supplementary variable technique. The effects of failure rates and coverage factor in the performance of gas turbine have been discussed.

Bi-directional system analysis under copula-coverage approach

ABSTRACT Reliability assessment is a major step, toward the development of fault-tolerant computing system. In different fields of engineering and physical/ailed sciences, researchers or engineers have several reliability approaches for the better performance of the system. By assuming different types of time trends, failure modes and repair effects, the legion stochastic model has been developed for repairable system. This study shows a novel concept for three state fault tolerant repairable systems with two types of repair. This research predicts the effect of the coverage factor using Gumbel-Hougaard family of copula approach on reliability characteristics of the designed system.

Sensitivity analysis of a three-unit series system under k-out-of-n redundancy

Purpose The purpose of this paper is to investigate the reliability measures, namely, availability, reliability, mean time to failure and expected profit. The authors also analyse the sensitivity of these reliability measures. Design/methodology/approach Depending upon the real industrial relevance, a generalized system which is easily repairable, extremely reliable and of high quality is expected by the rapid growth of the digital economy. Considering reliability, as one of the performance measure, the authors have designed a complex system which consists of three subsystems, namely, A, B and C in series configuration. The subsystem A consists of n numbers of units which are arranged in parallel configuration, subsystem B consists of two sub-subsystems X and Y align parallel to one another, where X is a type of 1-out-of-n:F. Failure and repair rates are assumed to be follow the general distribution. Findings The system is deeply studied by the usage of the supplementary variable technique, Laplace transformation and Markov’s law. Various conclusive results such as availability and reliability of the system, mean time to failure, cost and sensitivity analysis have been discussed further. Originality/value Through the systematic view of reliability measures of the proposed system, performance of the system can be enhanced under high profit.

Stochastic modelling of a wind electric generating power plant: Performance under multi-approaches

Purpose The purpose of this paper is to analyse the performance of a wind electric generating power plant through the study of reliability measures. The enhancement of the performance of the wind power plant using various approaches is also an objective of this paper. Design/methodology/approach This paper describes two models of a wind electric generating power plant using the Markov process and supplementary variable technique and solved with the help of Laplace transformation. The first model has been analyzed without fault coverage and Gumbel-Hougaard family of copula, while the second model of the wind power plant employs fault coverage and Gumbel-Hougaard family of copula which are used to enhance the performance. The proposed methodology is then illustrated in detail considering numerical examples. Findings Numerous reliability characteristics such as availability, reliability and mean time to failure to examine the performance of the wind power plant have been investigated. Through the comparative study of both the models, the authors concluded that the plant can generate electricity over long periods of time by covering more and more detected faults, which is made possible with two types of repair facility. Originality/value In this work, the authors have developed a mathematical model based on a wind electric generating power plant. This work incorporates not only the component failures that stop or degrade the working of the plant but also deals with the catastrophic and repair strategy of the plant.

Reliability Measures Analysis of a Computer System Incorporating Two Types of Repair Under Copula Approach

In this chapter, the authors have studied the reliability characteristics of a home or office based computer system constructed with hardware connectivity. The system contains multi possible stages that can be repaired. The designed system is studied by using the Markov process, supplementary variable technique, Laplace transformation, and Gumbel–Hougaard family of copula to obtain the various reliability measures such as transition state probabilities, availability, reliability, cost analysis, and sensitivity.

Elevator System Analysis in Deliberation of Dependability, Cost Under Coverage, and Copula Approaches

This chapter investigates the reliability measures of an elevator system under the study of different failures. The considered system consists of car which is loaded with steel cables and attached by guide rails for up and down motion, and these steel cables are further attached by the pulley and gearbox system on the top of the building or on the uppermost section of the unit. The elevator faults affect not only the operations of other assets but may also result in injuries or even death. So, governor and breaks are also fitted to have a control over speed and sudden failure. Steel cables are also used in a large number to prevent the accident due to cable failure or complete fracture. The authors also analyze the expected profit in the system after the examination of maintenance cost. They are employing the coverage factor technique to enhance the lifetime of the system along with the birth-death stochastic model of elevator and have also taken some numerical examples of the real impact of these measures. The results of the proposed model offer an effective technique for elevator maintenance. Finally, the authors demonstrate the behavior of each parameter graphically.

Carburettor Performance Under Copula Repair Strategy

This paper proposes an efficient study about the performance of the carburettor system for the analysis of the reliability characteristics subjected to the Gumbel–Hougaard family of copula with the required repairs facility. The problem has been solved by constructing the state transition model of the carburettor, considering together the supplementary variable technique and Markov process. In this research work, the authors tried to predict the various reliability indices to investigate the performance of the carburettor system with the deliberation of different types of failures occur in it. The performance of carburettor directly depends upon the working of some of its components. Furthermore, the sensitivity of the carburettor system has also been investigated for each reliability characteristic in context of their input parameters, which is very helpful and necessary for attaining a highly reliable carburettor system. At the end of the study, some numerical examples and their graphical representation have also been taken to highlight the practical utility of the model.

Performability of solar thermal power plant under reliability characteristics

The present paper deals with the study of the solar thermal power plant with the help of Markov process by the consideration of different failure and repairable facilities. A probabilistic model of the system has been developed through considering some assumptions. Authors have considered three types of failures such as equipment failure, non-availability of fluid and environmental failure. The present system under the study, consists of three possible states: good, degraded (partially failed) and completely failed state. Using supplementary variable technique and Markov process, a successful attempt has been made to evaluate the probability of each state and various important performance measures. Finally; some numerical examples and graphically representation are shown at the end.

Software reliability growth modeling for agile software development

Abstract The frequent incremental release of software in agile development impacts the overall reliability of the product. In this paper, we propose a generic software reliability model for the agile process, taking permanent and transient faults into consideration. The proposed model is implemented using the NHPP (non-homogenous Poisson process) and the Musa model. The comparison of the two implementations yields an effective, empirical and reliable model for agile software development.