manufacturers need to evaluate the reliability of their products in order to increase the customer satisfaction. proper analysis of reliability also requires an effective study of the failure process of a product, especially its failure time. so, the failure process modeling (fpm) plays a key role in the reliability analysis of the system that has been less focused on. this paper introduces a f...

A hybrid censoring scheme is a mixture of type I and type II censoring schemes. When $n$ items are placed on a life test, the experiment terminates under type I or type II hybrid censoring scheme if either a pre-fixed censoring time T or the rth (1<=r<=n&nbsp;is fixed) failure is first or later observed, respectively. In this paper, we investigate the decomposition of entropy in both hybrid cen...

Broken adaptive ridge (BAR) is a computationally scalable surrogate to $$L_0$$ -penalized regression, which involves iteratively performing reweighted $$L_2$$ penalized regressions and enjoys some appealing properties of both while avoiding their limitations. In this paper, we extend the BAR method semi-parametric accelerated failure time (AFT) model for right-censored survival data. Specifical...

Effects such as student dropout and the non-normal distribution of duration data confound the exploration of tutor efficiency, time-intutor vs. tutor performance, in intelligent tutors. We use an accelerated failure time (AFT) model to analyze the effects of using automatically generated hints in Deep Thought, a propositional logic tutor. AFT is a branch of survival analysis, a statistical tech...

Failure or degradation of the flight control system, or hull damage, can lead to loss of vehicle control during entry. Possible failure scenarios are debris impact and wing damage that could result in a large aerodynamic asymmetry which cannot be trimmed out without additional yaw control. Currently the space shuttle uses aerodynamic control surfaces and Reaction Control System jets to control ...

1 0-7803-5846-5/00/$10.00 © 2000 IEEE Abstract— This paper describes the design and implementation of a software infrastructure for real-time fault tolerance for applications on long duration deep space missions. The infrastructure has advanced capabilities for Adaptive Fault Tolerance (AFT), i.e., the ability to change the recovery strategy based on the failure history, available resources, an...

In this paper, a new servicing strategy with imperfect repair is defined and studied for the manufacturer of a product sold with a two-dimensional warranty. The strategy is based on a specified region of the warranty defined in terms of age and usage, with the first failure in the region rectified by an imperfect repair and all other failures being minimally repaired. Product failures are model...

â liquefied natural gas (lng) is the most economical way of transporting natural gas (ng) over long distances. liquefaction of ng by using vapor compression refrigeration system requires high operating and capital cost. due to lack of systematic design methods for multistage refrigeration cycles, the conventional approaches of determining optimal cycle configuration are mostly based on trial-an...

Bridge deck deterioration modeling is critical to infrastructure management. Deterioration traditionally done using deterministic models, stochastic and recently basic machine learning methods. The advanced learning-based survival such as random forest, have not been adapted for use in This paper introduces forest models bridge compare their performance with a commonly used traditional model, t...