Hybrid journal (It can contain Open Access articles) ISSN (Print) 1479-389X - ISSN (Online) 1479-3903 Published by Inderscience Publishers[439 journals]
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Authors:Bouba Oumarou Aboubakar, Hong Xia Li, Ahmadou Bouba Oumarou Pages: 1 - 26 Abstract: This paper, after assessing and ranking power shortage causes in Cameroon's northern Interconnected Grid, summarises the impact of power shortage on poor households and district hospitals. The results showed a drop of 40% of the supplied energy and the fluctuations of demand continued across the COVID-19 period till July in 2021 after lockdown, thus a low influence of the pandemic. The results also revealed a low influence of temperature and precipitations in the energy crisis. Instead, it was found that the most important factor that led to power shortage is electricity production cost which is higher than market price. Out of seven hypotheses tested by the structural model developed, five were significantly supported and two were rejected. The hypothesis testing showed that electrical fire safety and patient care in hospitals are both positively significantly affected by load shedding, hospital management and user's safety commitment and knowledge. Also, the results showed that neither safety knowledge nor safety impact is affected by demographic and socioeconomic variables. Using these results, a series of recommendations were given to energy practitioners and grid managers. Keywords: post COVID-19; load shedding; safety impact; structural equation modelling; Cameroon northern interconnected grid Citation: International Journal of Reliability and Safety, Vol. 16, No. 1/2 (2022) pp. 1 - 26 PubDate: 2023-01-30T23:20:50-05:00 DOI: 10.1504/IJRS.2022.128610 Issue No:Vol. 16, No. 1/2 (2023)
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Authors:Mohd Shariq, S.M. Anas, Mehtab Alam Pages: 27 - 45 Abstract: A detailed finite element micro-model of an Unreinforced Masonry (URM) wall of clay bricks, 1600 mm × 2100 mm × 240 mm, is made in ABAQUS/Explicit-v.6.15 code and analysed considering strain rate effects under the 5 kg-TNT explosion load at 0.58 m/kg<SUP align=right>1/3</SUP> scaled distance in free air. Results are validated with the available blast test results. Strengthening of the wall is considered by providing (1) steel wire mesh of diameter 2.50, 3.50 and 4.50 mm on the (a) rear face only and (b) on both the faces; (2) C-FRP wrapping of a thickness (a) 0.50 mm (b) 0.60 mm on the rear face only and (c) 0.30 mm on both the faces of the wall. Response of wall with each strengthening technique applied in this study is discussed. Application of 4.50 mm wire mesh on both the faces and 0.50 mm C-FRP sheet on the rear face makes the wall respond with comparable performance under the considered blast loading. Keywords: explosion loading; masonry walls; building safety; clay bricks; steel mesh; C-FRP wrapping; blast resistance; damage Citation: International Journal of Reliability and Safety, Vol. 16, No. 1/2 (2022) pp. 27 - 45 PubDate: 2023-01-30T23:20:50-05:00 DOI: 10.1504/IJRS.2022.128615 Issue No:Vol. 16, No. 1/2 (2023)
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Authors:P. Vijaya Laxmi, Andwilile Abrahamu George, Hasan Abdulkader Qrewi Pages: 46 - 73 Abstract: In this paper, we investigate the performance of batch service queue model with second optional service, repairable breakdown and warm standby server. Both primary operating and warm standby servers provide First Essential Service (FES) and Second Optional Service (SOS) to customers, wherein FES is all arriving customers and only some of them may further request the SOS. The service times, failure times and repair times of both primary operating and warm standby server are assumed to follow exponential distributions. We use Runge-Kutta method to obtain the transient state probabilities and matrix-decomposition method to obtain the steady-state probabilities of the model. Also, a cost model is presented to determine the optimal service rates so that the expected cost is minimised. Finally, the effect of the model parameters on the system behaviour is demonstrated through numerical results and discussions. Keywords: batch service queue model; first essential service; second optional service; repairable breakdown; standby server Citation: International Journal of Reliability and Safety, Vol. 16, No. 1/2 (2022) pp. 46 - 73 PubDate: 2023-01-30T23:20:50-05:00 DOI: 10.1504/IJRS.2022.128611 Issue No:Vol. 16, No. 1/2 (2023)
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Authors:Amisha Khati, Neelam Chantola, S.B. Singh Pages: 74 - 86 Abstract: In this research, a novel model for a Markov repairable system has been proposed wherein there is an uncertainty in the inspection period, i.e., the inspection period is taken in such a way that whenever a fault is identified throughout the inspection, the inspection period is shortened for the next inspection. Further, if the time taken to repair the system failure is less than the pre-determined critical value, the failed elements of the system are repaired. And, if the system takes longer than the critical time to fully recover, it is considered completely failed and then the failed system is replaced with a new one. The system is repaired under the (M/M/s):(∞/FCFS) queue model, including working vacations. We have evaluated the proposed model's availability as a measure of reliability. For clarification, the results are supported by a numerical example. Keywords: availability; Markov repairable system; uncertainty; critical repair time; (M/M/s):(∞/FCFS) queue Citation: International Journal of Reliability and Safety, Vol. 16, No. 1/2 (2022) pp. 74 - 86 PubDate: 2023-01-30T23:20:50-05:00 DOI: 10.1504/IJRS.2022.128612 Issue No:Vol. 16, No. 1/2 (2023)
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Authors:Hongxia Chen, Junfeng Zhang, Chenguang Li, Jihua Wang, Chuncheng Guo Pages: 87 - 109 Abstract: Research on the distribution of machine tool reliability indexes is of great significance to improve the reliability of machine tools in the design and manufacture stages. Owing to the complex structure of heavy-duty CNC machine tools, multi-source and heterogeneous failure causes, etc., the traditional single method cannot get accurate results. In this paper, based on the FTA method, a three-level machine tool fault tree model is established to carry out research on reliability index assignment. Then, as the levels progress, the distribution of reliability indicators is based on probability importance analysis, reliability redistribution method, and AHP respectively. Finally, the top-down reliability assignment results are obtained. After analysis, the structure obtained by combining multiple reliability allocation methods is more in line with the actual situation. According to the results, the weak parts of the machine tool are designed and improved, thereby improving the reliability of the machine tool. Keywords: heavy-duty CNC machine tool spindle system; FTA; reliability assignment; reliability index Citation: International Journal of Reliability and Safety, Vol. 16, No. 1/2 (2022) pp. 87 - 109 PubDate: 2023-01-30T23:20:50-05:00 DOI: 10.1504/IJRS.2022.128613 Issue No:Vol. 16, No. 1/2 (2023)
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Authors:Hamid El-Moumen, Nabil El Akchioui, Mohammed Hassani Zerrouk Pages: 110 - 123 Abstract: In our study, we were interested in the reliability of large discrete systems. These studies can be based on Markov models or on Stochastic Petri Nets (SPNs) that are generally used for the analysis and synthesis of the models used in the different phases of a system's life. Markov models or SPNs are perfect for many cases, still, they suffer from the combinatorial explosion when analytically their state numbers increase as the complexity of the dynamic systems grows accordingly with their components. Such issue reflects itself in the slowness of these models to accomplish convergence. These different modelling tools make it possible to deduce the average behaviour and to obtain the performance indicators of the system studied, either by calculation or by estimation. We will present the Markov analysis of a system whose state space is finite as well as its estimator obtained using SPNs. Keywords: Petri net; stochastic Petri net; stochastic estimator; Markov model; reliability analysis Citation: International Journal of Reliability and Safety, Vol. 16, No. 1/2 (2022) pp. 110 - 123 PubDate: 2023-01-30T23:20:50-05:00 DOI: 10.1504/IJRS.2022.128614 Issue No:Vol. 16, No. 1/2 (2023)