Faculty Publications
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Item Reliability Analysis of LHD Machine - A Case Study(Springer Nature, 2020) BalaRaju, J.; Govinda Raj, M.; Murthy, C.S.N.In the present global scenario, survival of the industry is more critical unless it produces their intended targets. Accomplishment of expected rate of production levels are depends on the performance of equipment. Hence, it is very important to predict the maintenance schedules for replacement or repair actions of the defective parts. Keeping in view, every industry is constantly looking for enhancement equipment life. Reliability analysis is one of the well appropriated techniques used to estimate the life of the equipment. In this paper, performance of Load-Haul-Dumper (LHD) has been analyzed. Renewal process approach has been utilized for reliability investigation. Best fit distribution of data sets were made by the utilization of Kolmogorov-Smirnov (K-S) test. Parametric estimation of theoretical probability distributions was done by utilizing Maximum Likelihood Estimate (MLE) method. Reliability of each individual sub-system has been computed according to the best fit distribution. In addition to that, reliability based preventive maintenance (PM) time schedules were calculated for the expected 90% reliability level. The possible recommendations were suggested for improvement of reliability level. © 2020, Springer Nature Switzerland AG.Item Identification of Reliability for an Automobile Sub-system Maruti Suzuki Alto(Springer Science and Business Media Deutschland GmbH, 2023) Varghese, L.; Jain, P.The present work aims to develop a statistical model to assess the reliability of different cars of the same model number. The input data were collected based on fault identification from an automobile service station. The data collection is categorized according to the distance covered by the cars, and this covered distance further converted into time function by considering the speed of cars as 60 km (km)/hour (hr). The data collection was categorized into three categories: (i) up to 25,000, (ii) 25,001–50,000 and (iii) 50,001–75,000 km’s to identify the various parameters of the study. To calculate the reliability, the Weibull distribution of two parameters, slope and scale was selected and applied. Results of reliability in terms of clutch, brake and suspension were calculated, and remedies were also suggested based on data received from the analysis. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item This paper deals with the cost analysis of a two-unit repairable system subject to on-line preventive maintenance (on-line PM) and/or repair. The policy adopted here is that the on-line PM work of the operating unit is undertaken first on its completion, the repair work of the failed unit, if any, is subsequently carried out. All the random variables that arise in the analysis are assumed to be independently and arbitrarily distributed. An expression for the expected total cost incurred by the system in a specified time interval is obtained by considering the expected busy period of the server spent on various actions. The analysis is carried out using the regeneration point technique. © 1992.(Cost analysis of a two-unit repairable system subject to on-line preventive maintenance and/or repair) Gopalan, M.N.; Bhanu, K.S.; Murulidhar, N.N.1992Item Estimating and prediction of turn around time for incidents in application service maintenance projects(Academy Publisher, 2008) Basavaraj, M.J.; Shet, K.C.Application Service Maintenance Projects normally deals with Incidents as First Level support function. Incidents in majority directly link with Production Environment, so Turn around Time for Incidents is a significant factor. Many Companies are having Service Level Agreements with Customer for Turn around Time for Incidents. There is a need to focus on Estimating and Predicting Turn around Time for Incidents. Improvement in Turn around Time helps in improving the Service Level Agreements earlier agreed with the Customer. Saved time can be diverted to other Project Activities like Enhancements or for new requests. This will also helps as one of the paths for Companies to get new business with the Customer. We have used Capability Maturity Model Integration(CMMI)V1.2 Quantitative Project Management(QPM) methodology for Application Service Maintenance(ASM) Projects for estimating and predicting turn around time for incidents. By implementing this best practice in SEI CMMI Level 5 Company we have achieved a significant improvement of approximately 50 percent reduction in Average Turn around Time for incidents. © 2008 Academy Publisher.Item Seawalls: Performance and their failure analysis along Southern Karnataka, West Coast of India(2012) Rao, S.; Hegde, A.V.; Dwarakish, G.S.; Janardhan, J.; Venkat Reddy, D.Beach erosion is a major problem along the south west coast of India. The beach erosion particularly along the south Karnataka coast is due to, 1) direct attack of waves in an open coast, which might have been intensified in some areas due to wave refraction, 2) erosion at river mouths where one or two rivers together join the sea. The coastal protection works adopted along the South Karnataka coast are mainly the seawalls. However, some portions of these seawalls have been damaged either partially or fully. A critical study shows that these failures are due to the scouring at the toe structure. Scouring causes the failure of the seawall due to loss of support. A calculated risk may be taken to design the seawall without taking scour depth into account but provide for adequate maintenance in case scour occurs and partial failure of the seawall takes place. © 2012 Cafet-Innova Technical Society. All rights reserved.Item Live migration of virtual machines with their local persistent storage in a data intensive cloud(Inderscience Enterprises Ltd. editor@inderscience.com, 2017) Modi, A.; Achar, R.; Santhi Thilagam, P.S.Processing large volumes of data to drive their core business has been the primary objective of many firms and scientific applications in these days. Cloud computing being a large-scale distributed computing paradigm can be used to cater for the needs of data intensive applications. There are various approaches for managing the workload on a data intensive cloud. Live migration of a virtual machine is the most prominent paradigm. Existing approaches to live migration use network attached storage where just the run time state needs to be transferred. Live migration of virtual machines with local persistent storage has been shown to have performance advantages like security, availability and privacy. This paper presents an optimised approach for migration of a virtual machine along with its local storage by considering the locality of storage access. Count map combined with a restricted block transfer mechanism is used to minimise the downtime and overhead. The solution proposed is tested by various parameters like bandwidth, write access patterns and threshold. Results show the improvement in downtime and reduction in overhead. © © 2017 Inderscience Enterprises Ltd.Item Reliability analysis and failure rate evaluation of load haul dump machines using Weibull distribution analysis(International Information and Engineering Technology Association info@iieta.org, 2018) Balaraju, R.J.; Govinda, R.M.; Murthy, C.S.N.Improvement of multifaceted system quality requires a group of complex design modifications. An expanding complexity of system is potentially prone to increase in the failure frequency. Continuous and random occurrence of failures in a system could be the main cause for performance drop of machinery. Theoritical probability distribution is one of the techniques used to estimate the lifetime of a system and its sub-systems with several failure considerations. One of the most extensively used statistical approaches for reliability estimation is a Weibull distribution. In the present paper a three-parameter Weibull distribution approach was adopted to analyze the data sets of Load-Haul-Dumper (LHD) in underground mines using 'Isograph Reliability Workbench 13.0' software package. The parameters were evaluated using best fit distributions and Weibull likelihood plots. Percentage reliability of each individual subsystem of LHD was estimated. Further, an attempt has been made to identify the preventive maintenance (PM) time intervals for enhancing the expected rate of reliability. © 2017 IIETA.Item Maintenance management of load haul dumper using reliability analysis(Emerald Group Holdings Ltd., 2020) Balaraju, B.; Govinda Raj, M.; Ch.S.N, M.Purpose: Load haul dumper (LHD) is one of the main ore transporting machineries used in underground mining industry. Reliability of LHD is very significant to achieve the expected targets of production. The performance of the equipment should be maintained at its highest level to fulfill the targets. This can be accomplished only by reducing the sudden breakdowns of component/subsystems in a complex system. The identification of defective component/subsystems can be possible by performing the downtime analysis. Hence, it is very important to develop the proper maintenance strategies for replacement or repair actions of the defective ones. Suitable maintenance management actions improve the performance of the equipment. This paper aims to discuss this issue. Design/methodology/approach: Reliability analysis (renewal approach) has been used to analyze the performance of LHD machine. Allocations of best-fit distribution of data sets were made by the utilization of Kolmogorov–Smirnov (K–S) test. Parametric estimation of theoretical probability distributions was made by utilizing the maximum likelihood estimate (MLE) method. Findings: Independent and identical distribution (IID) assumption of data sets was validated through trend and serial correlation tests. On the basis of test results, the data sets are in accordance with IID assumption. Therefore, renewal process approach has been utilized for further investigation. Allocations of best-fit distribution of data sets were made by the utilization of Kolmogorov–Smirnov (K–S) test. Parametric estimation of theoretical probability distributions was made by utilizing the MLE method. Reliability of each individual subsystem has been computed according to the best-fit distribution. In respect of obtained reliability results, the reliability-based preventive maintenance (PM) time schedules were calculated for the expected 90 percent reliability level. Research limitations/implications: As the reliability analysis is one of the complex techniques, it requires strategic decision making knowledge for the selection of methodology to be used. As the present case study was from a public sector company, operating under financial constraints the conclusions/findings may not be universally applicable. Originality/value: The present study throws light on this equipment that need a tailored maintenance schedule, partly due to the peculiar mining conditions, under which they operate. This study mainly focuses on estimating the performance of four numbers of well-mechanized LHD systems with reliability, availability and maintainability (RAM) modeling. Based on the drawn results, reasons for performance drop of each machine were identified. Suitable recommendations were suggested for the enhancement of performance of capital intensive production equipment. As the maintenance management is only the means for performance improvement of the machinery, PM time intervals were estimated with respect to the expected rate of reliability level. © 2019, Emerald Publishing Limited.Item Application ANN Tool for Validation of LHD Machine Performance Characteristics(Springer, 2020) Balaraju, B.; Raj, G.R.; Murthy, C.S.Survival of industries has become more critical in the present global competitive business environment unless they produce their projected production levels. The accomplishment of this can be possible only by maintaining the men and machinery in an efficient and effective manner. Hence, it is more essential to estimate the performance of utilized equipment for reaching/achieving future goals. The present study focuses on the estimation of underground mining machinery such as the load–haul–dump machine performance characteristics using ‘Isograph Reliability Workbench 13.0’ software. The allocation of best-fit/goodness-of-fit distribution was made by utilizing the Kolmogorov–Smirnov test (K–S) test. The parameters were recorded based on the best-fitted results using the maximum likelihood estimate test. Further, a feed-forward-back-propagation artificial neural network (ANN) tool has been used to develop the models of reliability, availability and preventive maintenance time intervals. The number of neurons was selected with the Levenberg–Marquardt learning algorithm in the hidden layer as the optimal value. The output responses were predicted corresponding to the optimal values. Further, an attempt has been made to validate the computed results with ANN predicted responses. The recommendations are suggested to the industry based on the results for the improvement of system performance. © 2020, The Institution of Engineers (India).Item Performance Evaluation of Underground Mining Machinery: A Case Study(Springer, 2020) BalaRaju, J.; Govinda Raj, M.; Murthy, C.S.N.Unexpected occurrence of uneven breakdowns and their consequences have a significant influence on the equipment life. Hence, there is a need to discover the motives for the happening of critical potential failures and required repair or replacement action to control. Reliability analysis is utilized to approximate the performance of the equipment. In this study, the performance of the underground mining machinery known as load haul dumper (LHD) has been estimated with reliability analysis. The best-fit distribution of the data sets was selected by testing the numerous statistical distributions using the Kolmogorov–Smirnov (K-S) test. The percentage of reliability of each subsystem of the LHD machine was computed based on the best-fit approximation. The overall system reliability of the equipment was estimated using a series configuration-based reliability block diagram (RBD) approach. The reliability-based preventive maintenance (PM) time intervals were also computed for estimated 90.00% reliability. To accomplish the desired level of reliability, a review on maintenance programs should be made. Possible recommendations were made to the maintenance department in the industry for improvement in equipment. © 2020, ASM International.