Analytical Methods of Calculating the Lifetime Distribution for Some Models of Standby Redundant Systems (Published)
In present day technology, reliability of equipment’s is increased by employing the method of standby systems, that is, the introduction of extra units. The purpose of the supplementary units is to take over operation if the basic units break down. Moreover, to increase the effectiveness of standby systems, units that have failed are repaired. In this paper the reliability function and the mean lifetime are obtained for the cases of loaded, nonleaded and lightly loaded systems with and without renewal.Moreover, the effectiveness of repair is calculated for some distributions for different numbers of main units.
Keywords: Reliability, loaded, mean lifetime, nonloded and lightly loaded system., preventive maintenance, renewable system
Reliability Analysis of Symmetrical Columns with Eccentric Loading (Published)
This paper presents the reliability of the symmetrical columns with eccentric loading about one and two axes due to the maximum intensity stress and minimum intensity stress. In this paper a new lifetime distribution is introduced which is obtained by compounding exponential and gamma distributions (named as Lindley Distribution [L D]). Hazard rate, Mean time to failure has been discussed. It is observed from the results that the Reliability is decreasing when the load and scale parameter ( are increasing. It is observed that the area of cross section increased from 1000mm2 to 10000mm2 caused the increasing of reliability from 0.50 to 0.93 at minimum intensity.
Keywords: Eccentric load., Hazard rate Mean time to Failure, Intensity stress, Lindley distribution, Reliability
Characteristics of a System in Abnormal Weather Conditions by Using L Apl Ace Transforms (Published)
The research studies the availability and reliability to a system in which each unit of two modes, (normal, total failure) in two weather conditions- normal and stormy. To calculate reliability, the differential eq. of system resolved by Laplace Transform (L .T) depend on Complex imagine roots. Suppose the system rate of failure and rates of change of weather conditions are constant and the rate for repair of every unit are exponential distribution. The distribution of repair time be based on starting state of repair and not with the change in weather. we analysis graphically to watch the impress of several system parameters in mean time failure and availability.
Keywords: Availability, Change of Weather Conditions., Laplace transform., Mttf, Reliability, State Dependent System
Reliability and Availability Analysis of Two–Dissimilar Units by Using Laplace Transforms (Published)
The paper studies the reliability and availability of two dissimilar units. In order to calculate reliability, a state dependent system can be converted into the system of first order ordinary differential equations based on Laplace Transform technique. The system of ordinary differential equations is solved using Inverse Laplace depend on Complex Conjugate roots. Let failure rate and repair rate of each unit are taken as an exponential distribution. Availability, reliability and the mean time to failure are derived. We analysis graphically to observe the effect of various systems Parameters on the availability system and mean time to failure.
Keywords: Availability, Laplace transform., Mttf, Reliability, State Dependent System