scholarly journals Stochastic Analysis of Dis-Similar Standby System with Discrete Failure, Inspection and Replacement Policy

2016 ◽  
Vol 49 (2) ◽  
Author(s):  
J. Bhatti ◽  
A. K. Chitkara ◽  
M. K. Kakkar
Keyword(s):  
Geometric Distribution ◽  
Replacement Policy ◽  
Testing Strategy ◽  
Automatic Unit ◽  
Repair Rate ◽  
Regenerative Point ◽  
Inspection Policy ◽  
Repair Facility ◽  
System Effectiveness ◽  
Mean Time

AbstractThe device named autoclave used in pharma industries has been studied in this paper. This study provides the discussion how to obtain the reliability testing strategy of two dis-similar parallel units. The system is considered to be in operative condition if at least one out of two is in operative state. A single repair facility is available for repairing both kinds of failed units. In addition to repair mechanism, inspection policy has also been introduced for failed automatic unit. But the manual one does not require any such supervision facilty. Various essential measures of system effectiveness such as mean time to system failure (MTSF), steady state availability, busy period of supervisor and repairman are examined probabilistically by using geometric distribution and regenerative point techniques. A graph has been plotted to represent the behaviour of profit function and MTSF with respect to different failure and repair rate.

Reliability Analysis of Cold Standby Parallel System Possessing Failure And Repair Rate Under Geometric Distribution

2019 ◽  
Vol 13 ◽  
Author(s):  
Jasdev Bhatti ◽  
Mohit Kumar Kakkar
Keyword(s):  
Failure Rate ◽  
Geometric Distribution ◽  
Discrete Distribution ◽  
Maintenance Cost ◽  
Discrete Problem ◽  
New Techniques ◽  
Testing Strategies ◽  
Cold Standby ◽  
Mean Time ◽  
Iteration Technique

Background and Aim: With an increase in demands about reliability of industrial machines following continuous or discrete distribution, the important thing to be noticed is that in all previous researches where systems are having more than one failure no iteration technique has been studied to separate the failed unit on basis of its failure. Therefore, aim of our paper is to analyze the real industrial discrete problem following cold standby units arranged in parallel manner with newly concept of inspection procedure for failed units to inspect the exact failure and being communicator to the repairman for repairing exact failed part of unit for saving time and maintenance cost. Methods: The geometric distribution and regenerative techniques had been applied for calculating different reliability measures like mean time to system failure, availability of a system, inspection, repair and failed time of unit. Results: Graphical and analytical study had also been done to analyze the increasing/decreasing behavior of profit function w.r.t repair and failure rate. The system responded properly in fulfilling his basic needs. Conclusion: The calculated value of all reliability parameter is helpful for studying any other models following same concept under different environmental conditions. Thus, it concluded that, reliability increases/decreases with increase in repair/failure rate. Also, the evaluated results by this paper provides the better reliability testing strategies that helps to develop new techniques which leads to increase the effectiveness of system.

Inspecting Briquette Machine with Different Faults

2020 ◽  
Vol 13 ◽  
Author(s):  
Divesh Garg ◽  
Reena Garg ◽  
Vanita Garg
Keyword(s):  
Failure Rate ◽  
Rate Increase ◽  
Practical Importance ◽  
System Failure ◽  
Regenerative Point ◽  
Semi Markov Process ◽  
Major Fault ◽  
Environment Study ◽  
Burning Coal ◽  
Mean Time

Background: A briquette machine can be considered very useful in modern times as the need of energy consumption is increasing rapidly. Considering the harm to environment, study of briquette machine is the need of present times. In this paper, the operative unit is considered as briquette machine also known as bio-coal which is used for agroforestry waste. Objective: A single operative unit has been analyzed stochastically. The inspection of breakdown of a unit reveals the feasibility of the unit under the supervision of either ordinary or expert repairmen. Two types of fault are revealed by the repairmen either minor or major fault. Minor faults are repaired immediately by the same repairmen but whenever major fault held, the machine’s fault will be handled by expert person. Method: It is assumed that the repair needs no modification once served. Availability, Mean-time for system failure, and profits are analyzed by utilizing the Regenerative point graphical technique and semi-Markov process. Result: Study reveals that the Mean-time for system failure of the system model go on decreasing as failure rate increase and availability goes on decreasing as failure-rate increase. Moreover, the study shows that the systems profit goes down on increase of Failure-rate. Conclusion: Findings of the study supports the hypothesis that the limits of failure/repair/inspection rate will surely have effective profitability. Moreover, it is found that the utility of scale of operation can easily be derived. The practical importance of biomass briquettes for burning coal or wood is very well appreciated.

On classes of life distributions based on the mean time to failure function

2021 ◽  
Vol 58 (2) ◽  
pp. 289-313
Author(s):  
Ruhul Ali Khan ◽  
Dhrubasish Bhattacharyya ◽  
Murari Mitra
Keyword(s):  
Damage Model ◽  
Replacement Policy ◽  
Time To Failure ◽  
Mean Time To Failure ◽  
Moment Convergence ◽  
Life Distributions ◽  
Cumulative Damage Model ◽  
The Mean ◽  
Age Replacement ◽  
Mean Time

AbstractThe performance and effectiveness of an age replacement policy can be assessed by its mean time to failure (MTTF) function. We develop shock model theory in different scenarios for classes of life distributions based on the MTTF function where the probabilities $\bar{P}_k$ of surviving the first k shocks are assumed to have discrete DMTTF, IMTTF and IDMTTF properties. The cumulative damage model of A-Hameed and Proschan [1] is studied in this context and analogous results are established. Weak convergence and moment convergence issues within the IDMTTF class of life distributions are explored. The preservation of the IDMTTF property under some basic reliability operations is also investigated. Finally we show that the intersection of IDMRL and IDMTTF classes contains the BFR family and establish results outlining the positions of various non-monotonic ageing classes in the hierarchy.

scholarly journals Multi-Machine Repairable System with One Unreliable Server and Variable Repair Rate

Mathematics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1299
Author(s):  
Shengli Lv
Keyword(s):  
Steady State ◽  
Transient State ◽  
Repairable System ◽  
Repair Rate ◽  
Numerical Illustration ◽  
Transform Method ◽  
Unreliable Server ◽  
Busy Time ◽  
The Mean ◽  
Mean Time

This paper analyzed the multi-machine repairable system with one unreliable server and one repairman. The machines may break at any time. One server oversees servicing the machine breakdown. The server may fail at any time with different failure rates in idle time and busy time. One repairman is responsible for repairing the server failure; the repair rate is variable to adapt to whether the machines are all functioning normally or not. All the time distributions are exponential. Using the quasi-birth-death(QBD) process theory, the steady-state availability of the machines, the steady-state availability of the server, and other steady-state indices of the system are given. The transient-state indices of the system, including the reliability of the machines and the reliability of the server, are obtained by solving the transient-state probabilistic differential equations. The Laplace–Stieltjes transform method is used to ascertain the mean time to the first breakdown of the system and the mean time to the first failure of the server. The case analysis and numerical illustration are presented to visualize the effects of the system parameters on various performance indices.

An Improvement Inspection Policy for C2F6 Gas Used in Semiconductor Manufacturing

2013 ◽  
Vol 389 ◽  
pp. 175-182
Author(s):  
I Ping Huang ◽  
Chiuh Cheng Chyu
Keyword(s):  
Cost Reduction ◽  
Semiconductor Manufacturing ◽  
Geometric Distribution ◽  
Estimation Method ◽  
Cost Savings ◽  
Influence Diagram ◽  
Product Failure ◽  
Total Cost ◽  
Failure Cost ◽  
Inspection Policy

This research proposes an inspection policy aiming to improve the application of C2F6 in semiconductor manufacturing. For the gas product C2F6, total inspection is commonly employed by the producers before it is sent to downstream manufacturers. The study develops a Bayesian rectifying inspection sampling model with the objective of minimizing expected total cost from the producers standpoint. The factors that influence the total cost include gas product quality, inspection cost, sampling information, product failure cost, inspection accuracy, and decision on the remaining units. Influence diagram is used to represent the problem and derive the total objective function. The application of the model is presented via a real world company using the last four years of data. The proposed inspection policy yields an average of 15% cost savings using a cost reduction estimation method based on hyper-geometric distribution.

OPTIMAL PERIODIC REPLACEMENT POLICY WITH CHECKING TIME

2005 ◽  
Vol 12 (01) ◽  
pp. 19-29 ◽  
Author(s):  
SHEY-HUEI SHEU ◽  
YAN-CHUN CHEN ◽  
LI-HSIU TENG
Keyword(s):  
Optimal Number ◽  
Replacement Policy ◽  
Inspection Time ◽  
Programming Formulation ◽  
Minimal Repair ◽  
Repair Costs ◽  
Inspection Strategy ◽  
Inspection Policy ◽  
Periodic Replacement ◽  
Replacement Time

This investigation considers a generalized inspection policy for a deteriorating production system with general random minimal repair costs. The inspection times for the inspection strategy are assumed to be non-negligible. Additionally, uncertainty probabilities associated with inspections are introduced. Using a dynamic programming formulation, the optimal inspection time for maximizing profit per unit time for a given overhaul/replacement time is determined. Next, the procedure is extended to determine the optimal periodic overhaul/replacement time, as well as the optimal number of inspections and their schedule.

A MARKOV REPAIRABLE SYSTEM INVOLVING AN IMPERFECT SERVICE STATION WITH MULTIPLE VACATIONS

2005 ◽  
Vol 22 (04) ◽  
pp. 555-582 ◽  
Author(s):  
JAU-CHUAN KE ◽  
CHUEN-HORNG LIN
Keyword(s):  
Repairable System ◽  
System Failure ◽  
Service Station ◽  
System Parameters ◽  
Failure Frequency ◽  
The Mean ◽  
Repair Facility ◽  
Markov Repairable System ◽  
Mean Time ◽  
Reliability And Availability

The main purpose of this paper is to study the reliability and availability of a system with M operating devices, m spares, and an imperfect service station that takes vacations. Specifically, once there are no failed devices in the system, the service station takes consecutive vacations until there is at least one failed device upon its return from vacation. The service station may break down and require repair at a repair facility. This paper derives the reliability, the mean time to system failure, the availability, and failure frequency of the K-out-of-M + m system. Numerical simulation of the impacts of system parameters as well as sensitivity analysis for the reliability, the mean time to system failure, the availability and failure frequency is performed.

scholarly journals Reliability Analysis of Two Unit Standby Model with Controlled and Uncontrolled Failure of Unit and Replacement Facility Available in the System

2021 ◽  
pp. 625-632
Author(s):  
Nafeesa Bashir ◽  
JPS Joorel ◽  
T R Jan
Keyword(s):  
Present Model ◽  
Design Strategy ◽  
Replacement Policy ◽  
System Failure ◽  
Reliability Measures ◽  
Primary Interest ◽  
Efficient System ◽  
Regenerative Point ◽  
Regenerative Point Technique ◽  
Preventive Repair

Planning a highly reliable and efficient system has always been a primary interest for reliability engineers by devising the powerful design strategy and employing effective repair and replacement policy. Keeping in view this, the basic aim of this paper is to analyze the reliability of a system which comprised of two units A and B in which unit A is functional and B is held standby. Unit A after failure may be controlled or uncontrolled. The failed unit undergoes for repair in the controlled unit. If the repair of a unit is not controlled then it is replaced by a new one.  Upon the breakdown of operational unit A, unit B come becomes active instantaneously. Unit B after failure is repaired by regular repairmen. System failure takes place when both the units quit serving. The unit serves as good as a fresh after preventive repair and replacement policy. The regenerative point technique has been used to obtain the expression for several reliability measures. Finally, the graphical behavior of MTSF and profit of the present model has been observed for arbitrary values of parameters and costs.

scholarly journals Probabilistic Assessment of Two-Unit Parallel System with Correlated Lifetime under Inspection Using Regenerative Point Technique

2019 ◽  
Vol 2 (1) ◽  
pp. 5-14
Author(s):  
VIJAY VIR SINGH ◽  
PRAVEEN KUMAR POONIA
Keyword(s):  
Mathematical Formulation ◽  
Practical Importance ◽  
Joint Probability ◽  
General Distribution ◽  
Regenerative Point ◽  
Negative Exponential Distribution ◽  
Parallel Configuration ◽  
Regenerative Point Technique ◽  
Repair Facility ◽  
Negative Exponential

This paper deals with the reliability analysis of a complex system consisting ofa two dissimilar unit’ in a parallel configuration with correlated lifetime distribution. The system stops functioning when both units stop working. Both units are inspected periodically as well as being examined before assigning to repair facility. Under consideration of the system have two states: Normal and failed. Regenerative point technique has been used for the mathematical formulation of the model. The system is analyzed using Laplace transforms to solve the mathematical equations. Reliability, Availability, MTSF, Busy Period of repairmen and Cost-effectiveness of the system has been computed. The computed results have been demonstrated by tables and graphs. The repair time of both the units follows the negative exponential distribution with different parameters in a joint probability density function. The inspection times are assumed to follow the general distribution. Some particular cases of the system have also been derived from seeing the practical importance of the model.

scholarly journals Reliability and Availability Analysis of Arepairable System With Two Types of Failure

2015 ◽  
Vol 4 (1) ◽  
pp. 39
Author(s):  
M. A. El-Damcese ◽  
M. S. Shama
Keyword(s):  
System Reliability ◽  
Repairable System ◽  
Time To Failure ◽  
Repair Rate ◽  
System Parameters ◽  
Availability Analysis ◽  
Reliability Characteristics ◽  
The Mean ◽  
Mean Time ◽  
Reliability And Availability

This paper investigates reliability and availability of a repairable system with two types of failure. Let failure rate and repair rate of [type1, type2] components are assumed to be exponentially distributed. The expressions of availability and reliability characteristics such as the system reliability and the mean time to failure are derived. We used several cases to analyze graphically the effect of various system parameters on the reliability system and availability system.

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