Abstract In this paper, a repairable system of a monotone process model for a one-component multistate degenerative system with (k + 1) states(k-failure states and one working state) is studied. Also an alternative model, called the Negligible Or Non-Negligible (NONN) repair times introduced by Thangaraj and Rizwan (2001) is incorporated in this model to develop some new repair models. A replac...

The replacement patterns of Ascaris lumbricoides worm populations were investigated by complete deworming of 150 Filipino children (0-14 years old) from both urban and rural barangays and analyzing the age distribution of the 2,072 adult worms (939 males and 1,133 females) obtained, based on Seo's (1983) regression equation relating length to age. It was observed that most worm populations foll...

The earnings replacement rates of retired couples, which take into account the earnings and benefits of wives, are important for assessing the adequacy of social security benefits. Using data from the Social Security Administration’s longitudinal Retirement History Study, this article presents the first view of replacement rates for couples. The findings show that, though about half the wives c...

Condition-based maintenance has been proven effective in reducing unexpected failures with minimum operational costs. This study considers an optimal condition-based replacement policy with optimal inspection interval when the degradation conforms to an inverse Gaussian process with random effects. The random effects parameter is used to account for heterogeneities commonly observed among a pro...

We consider an age-replacement model with minimal repair based on a cumulative repair cost limit and random lead time for replacement delivery. A cumulative repair cost limit policy uses information about a system's entire repair cost history to decide whether the system is repaired or replaced; a random lead time models delay in delivery of a replacement once it is ordered. A general cost mode...

We measured the plasma 25-hydroxyvitamin D(3) (25(OH)D(3)) levels in 62 consecutive Caucasian patients undergoing total hip replacement for osteoarthritis. The patients were divided into two groups based on whether they were vitamin D sufficient or deficient. The groups were matched for age, gender and the American Society of Anaesthesiologists (ASA) grade. The prevalence of vitamin D deficienc...

in industries, preventive maintenance (pm) is not a new practice to minimise the sudden breakdown of production machine. pm will be performed at predetermine intervals to provide a balance between failure cost and component utilisation (aging). however, most of pm interval is based on experience or original equipment manufacturer (oem) recommendations. consequently, the benefits from pm are not...

Unexpected system failures pose significant problems in power industry and most manufacturing companies. In some cases, a critical component failure can incur catastrophic events and huge economic loss. To maintain machines at high level of reliability, some companies perform time-based preventive maintenance or age-based preventive maintenance to avoid sudden failure of machines. Usually, prev...

In This Paper, we focus on estimating the expected total cost and expected cost rate for age replacement under warranty policy. We describe how to use design of Accelerated life testing (ALT) plans by assuming constant stress and life times are independently distributed as Exponentiated Pareto Distribution (EP) for predicting the cost of age replacement under warranty policy. This problem is st...

— This paper summarizes ten replacement models which combine tkree basic replacements: (i)age replacement; (ii)block replacement; (in) periodic replacement with minimal repair at failure. The expected cast rates ofeach model are derived, using the usual caktdus method ofprobabitity. As an example, we give an optimum policy to minimize the expected cost rate ofone model