This paper reports a manner to use a Bayesian approach to derive the optimal replacement policy. In order to produce a system with minimal repair warranty, a replacement model with the extended warranty is considered. Within the warranty period, the failed system is minimally repaired by the manufacturer at no cost to the end-user. The failure time is assumed to follow a Weibull distribution with unknown parameters. The expected cost rate per unit time, from the end-user's viewpoints, is induced by the Bayesian approach, and the optimal replacement policy to minimize the cost rate is proposed. Finally, a numerical example illustrating to derive the optimal replacement policy based on the Bayesian approach is described.

Because of financial and safety concerns, there are needs for more accurate prediction of bridge behavior. Underestimation of the bridge load carrying capacity can have serious economic consequences, as deficient bridges must be repaired or rehabilitated. Therefore, the knowledge of the actual bridge behavior under live load may lead to a more realistic calculation of the load carrying capacity and eventually this may allow for more bridges to remain in service with or without minor repairs. The presented research is focused on the reliability evaluation of the actual load carrying capacity of existing bridges based on the field testing. Seventeen existing bridges were tested under truck load to confirm their adequacy of reliability. The actual response of existing bridge structures under live load is measured. Reliability analysis is performed on the selected representative bridges designed in accordance with AASHTO codes for bridge component (girder). Bridges are first evaluated based on the code specified values and design resistance. However, after the field testing program, it is possible to apply the experimental results into the bridge reliability evaluation procedures. Therefore, the actual response of bridge structures, including unintentional composite action, partial fixity of supports, and contribution of nonstructural members are considered in the bridge reliability evaluation. The girder distribution factors obtained from the tests are also applied in the reliability calculation. The results indicate that the reliability indices of selected bridges can be significantly increased by reducing uncertainties without sacrificing the safety of structures, by including the result of field measurement data into calculation.

Since The Korean Reliability Society had been founded in 1999, development history of reliability engineering in Korea is reviewed and research outputs and papers from 2008 to current are analyzed in terms of types of industry, product life cycle, hardware vs software, and theory vs application. The purpose of this research is to review the recent reliability engineering research conducted in Korea including development history as well as published papers to identify the weakness and/or deficiencies in order to suggest the future research directions, which would contribute the development of industries in Korea.

Because process variations have direct influence on yield rate in process industry, it is very important to understand process variations that occur accidentally. In process industry, quality variation due to the activities of process improvement and maintenance and chance effect such as change of work environment and difference in staffs' craftsmanship are mixed with each other, therefore it is difficult to actually detect minute process variations. In this study, objective and rational methods of detection that can detect minute process variations in process industry were designed referring to various methodologies of process management, and they were verified through similar examples.

This paper presents a case study of PSD(Platform Screen Door) system assurance based on EN50126 life-cycle stage. By applying this system assurance, the accidents related to urban light transit railway especially that caused casualties could be reduced tremendously. This case study contributes significantly to the reliability, availability, maintainability and safety of the PSD system. Request For Proposal (RFP) of a rail road operator in which required by RAMS is prepared in which to ensure all system assurance activity and safety assessment are compulsory. The step-by-step activities and related deliverables are used which include functional analysis, FMECA, hazard identification analysis, system hazard analysis, maintainability analysis, FRACAS, and finally verification and validation of the system.

The value of blood sugar is measured by a personal blood glucose meter which consists of two parts: a glucose strip and a blood glucose meter. A personal blood glucose meter makes use of electric media which are composed of glucose oxidase and electron. This study is to propose a method of reliability demonstration test derived from field data analysis and FMEA(Failure Mode and Effect Analysis). Detailed Conditions for reliability demonstration test are selected from the comparison of various failure mechanisms. The most dominant failure mechanism is wear-out which is caused by strip insertion/extraction. The testing device that can reproduce the failure mechanism of strip insertion/extraction is made to conduct reliability demonstration test. Using the testing device, it is confirmed that target lifetime of selected devices is more than 2 years.