We consider opportunity-based age replacement using nonparametric predictive inference (NPI) for the time to failure of a future unit. Based on n observed failure times, NPI provides lower and upper bounds for the survival function for the time to failure Xn+1 of a future unit, which lead to upper and lower cost functions, respectively, for opportunitybased age replacement based on the renewal ...

The early age shrinkage is responsible for the early age cracking of concrete. It is very critical for durability of concrete. The change in volume of concrete due to evaporation of water or dehydration process is known as shrinkage. To reduce the early age shrinkage utilized the supplementary cementitious material (SCM) in concrete. In present research industrial and agricultural waste byprodu...

An age replacement maintenance policy is considered here, in which a system is restored whenever it fails, or ages without failure up to a preventive maintenance epoch (whichever comes first). The duration of the restoration activity is random, and depends on whether it was precipitated by a failure or by a preventive maintenance action. The case where the preventive maintenance epoch is determ...

Biologic valve re-replacement was examined in a series of 1343 patients who underwent aortic valve replacement at The Prince Charles Hospital, Brisbane, with a cryopreserved or 4 degrees C stored allograft valve or a xenograft valve. A parametric model approach was used to simultaneously model the competing risks of death without re-replacement and re-replacement before death. One hundred eleve...

The aim of this study is to determine the priority areas in meter replacement or rehabilitation by using an integrated methodology combining AHP and ELECTRE I methods reduce non-revenue water. For this, a total 7 criteria such as Water Consumption Rate, Mean Meter Age, Faulty Ratio, Region Population Customer Loyalty Percentage, Average Operating Pressure Calibrated Age were considered. method ...

putative activity of hydroalcoholic and aqueous infusion extracts of echium amoenum l. was investigated in mice using the rotarod model of motor coordination and the elevated plus maze model of anxiety. the extracts were administered intraperitonealy (i.p.) once, one hour before performing the tests. preliminary phytochemical study of the plant, with standard procedures, showed that it contains...

This study aimed at presenting a method for formulating optimal production, repair and replacement policies. The system was based on the production rate of defective parts and machine repairs and then was set up to optimize maintenance activities and related costs. The machine is either repaired or replaced. The machine is changed completely in the replacement process, but the productio...

With the evolution of technology, the maintenance of sophisticated systems is of concern for system engineers and system designers. The maintenance cost of the system depends in general on the replacement and repair policies. The system replacement may be in a strictly periodic fashion or on a random basis depending upon the maintenance policy. At failure, the repair of the system may be perfor...

AbstractChromosomal translocations constitute one of the most important, yet uncommon, causes of primary amenorrhea and gonadal dysgenesis. Although X-autosome translocations are frequently associated with streak gonads and clinical features of the Turner syndrome, the majority of X-autosome carriers may present with a variable phenotype, developmental delay, and recognizable X-linked syndrome ...

In this article, two different systems subject to shocks occurring based on a non-homogeneous Poisson process (NHPP) are analyzed. Type –I system is consisted of a single unit and type –II system is consisted of two parallel units in which both units operate identically and simultaneously. In type –I system occurrence of a shock causes system stopping and consequently will be received minimal r...