• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.52-60
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• 2007

Estimating parameters of the lifetime distribution is investigated when field failure data are not completelyreported. To take into account the reality and the accuracy of the estimates in such a case, the failure reportingprobability is incorporated in estimating parameters, Firstly, method of maximum likelihood estimate (MLE) isused to estimate parameters of the lifetime distribution when failure reporting probability is known, Secondly,Expectation and Maximization (EM) algorithm is used to estimate the failure reporting probability and parame-ters of the lifetime distribution simultaneously when failure reporting probability is unknown. For both cases,procedures of estimation are illustrated for single Weibull distribution and mixed Weibull distribution. Simula-tion results show that MLE obtained by the proposed method is more accurate than the conventional MLE.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.678-685
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• 2005

Estimating parameters of the lifetime distribution is investigated when field failure data are not completely reported. To take into account the reality and the accuracy of the estimates in such a case, the failure reporting probability is incorporated in estimating parameters. Firstly, method of maximum likelihood estimate(MLE) is used to estimate parameters of the lifetime distribution when failure reporting probability is known. Secondly, Expectation and Maximization(EM) algorithm is used to estimate the failure reporting probability and parameters of the lifetime distribution simultaneously when failure reporting probability is unknown. For both case, procedures of estimation are illustrated for single Weibull distribution and mixed Weibull distribution. Simulation results show that MLE obtained by the proposed method is more accurate than the conventional MLE.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.24 no.1
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• pp.33-40
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• 2016

ROK issued its first type certificate to the KC-100 airplane, Part 23 normal category, and become the State of Design (SoD) in 2013. Before this, ROK aviation regulations were focused on the operation and continued airworthiness of aircraft registered and operated in ROK that were designed and manufactured in another contracting state. Therefore the implementation of reporting system were restricted to gather the failure and service difficulty reports from the owners or operators and transmit the information to the State of Design and/or the manufacture relating to the type certificated aircraft. However, ROK, to fulfill the accountability of the State of Design, has to ensure there is a system to address the information received from the State of Registry on failure, malfunctions, defects and other occurrences that might cause adverse effects on the continuing airworthiness of the korean type certificated aircraft. This paper presents an overview of ICAO requirements for the State of Design, and current implementation of reporting system of USA and Japan and discusses the current status and further considerations on the rule-making for the malfunction, defect and failure reporting system applicable to the korean indigenous aircraft.

• 한국데이터정보과학회:학술대회논문집
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• 2006.11a
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• pp.97-112
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• 2006

FRACAS(Failure Reporting, Analysis and Corrective Action System) is intended to provide management visibility and control for reliability and maintainability improvement of hardware and associated software by timely and disciplined utilization of failure and maintenance data to generate and implement effective corrective actions to prevent failure recurrence and to simplify or reduce the maintenance tasks. This process applies to acquisition for the design, development, fabrication, test, and operation or military systems, equipment, and associated computer programs. This paper shows the FRACAS development process and developed FRACAS system for a defense equipment.

• Management & Information Systems Review
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• v.33 no.1
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• pp.173-190
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• 2014

According to COSO(2013) "Internal control is a process that is designed to provide reasonable assurance that a firm can achieve its objectives, where differing aspects of internal control can be partitioned into operating objectives, reporting objectives, and compliance objectives." Internal control over financial reporting(ICFR) is focus on reporting objectives and includes that provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the company's assets that could have a material effect on the financial statements. Thus, firms with weak ICFR have negative a effect on Firm value because those firms are great likelihood of misappropriation and inefficiency decision. In this regard, this study investigates the association of ICFR with the likelihood of firm failure. Specially, I measure the characteristic of ICFR as disclosures of material weaknesses and operating personnel of ICFR. I identify the likelihood of firm failure as going-concern opinion issued in audit report. As result, I find that a higher probability of firm failure is positively associated with the material weakness in ICFR also I find that a higher probability of firm failure is negatively associated with experience and qualified CPA of personnel in ICFR.

• Journal of Applied Reliability
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• v.8 no.3
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• pp.113-124
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• 2008

In reliability engineering, failure reporting, analysis, and corrective action system (FRACAS) is an useful tool for effective failure reporting and related operations. FRACAS is generally mainly focused on implementation of its closed-loop process, but also includes various related information which has to be effectively managed such as failure types, failure modes, failure mechanisms, and corrective actions. In this study, we adopt and utilize the concept of process knowledge, and create it through abstraction of FRACAS information. At each step of closed-loop process, the necessary type of knowledge, priority and usability are clearly defined. This study also suggests corresponding management tools such as business process management system, knowledge management system, and their key elements and functions to deal with process knowledge. A prototype system using simple closed-loop process with its process knowledge is presented to demonstrate the feasibility of the proposed work.

• Journal of Science and Technology Studies
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• v.12 no.1
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• pp.145-183
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• 2012

Science reporting is easier to lead to failure than other news reporting because it needs higher professionalism. According to Actor-Network Theory(ANT), not only research results(artifacts) of scientists but also science articles are hybrid networks. Namely, they are connected by human actors(scientist, reporter, etc.) and nonhuman actors(press releases etc.). When the process of science reporting is examined on the view of ANT, it is the process that scientists' results translate the media via press releases as intermediaries and expand their network to the public. This study aims at making an ANT analysis of how research results of Electronics and Telecommunications Research Institute(ETRI) scientist Hyun-Tak Kim were reported by lots of media, focusing on the rhetoric of ETRI's press release. It can reveal the reason for the science reporting's failure and hint at the better science journalism.

• 시스템엔지니어링워크숍
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• s.4
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• pp.81-85
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• 2004

시스템 엔지니어링은 시스템의 일생 주기동안 수행되며 고장정보체계(Failure Reporting and Corrective Action System)는 제작단계부터 수행되는 RAMS(Reliability, Availability,Manitani bility,safety)과업 중의 하나이다. 고장정보체계는 설계와 제작단계에서 생성된 고장원인을 제거하고 수정작업을 구현하기 위한 방법을 제공한다. 본 논문에서는 한국형 고속열차를 대상으로 고장정보 분석 및 관리, 신뢰도 평가를 위해 구축한 고장정보체계와 그 활용사례를 제시한다.

• Journal of the Korean Society of Systems Engineering
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• v.1 no.1
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• pp.39-45
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• 2005

Systems Engineering is the process that controls the technical system development effort with the goal of achieving an optimum balance of all system elements. FRACAS(Failure Reporting an d Corrective Action System) is one of RAMS(Reliability, Availability, Maintainability, Safety) tasks which is conducted from a manufacturing phase. FRACAS is to determine the basic cause of failure resulting from design or manufacture, and to provide a closed-loop method of implementing corrective action. This paper presents the FRACAS established for assessment of the reliability, the analysis and management of the failure data for Korean High Speed Train and application cases.

• Journal of the Korean Data and Information Science Society
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• v.21 no.1
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• pp.109-119
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• 2010

FRACAS (Failure Reporting, Analysis and Corrective Action System) is intended to provide management visibility and control for reliability and maintainability improvement of hardware and associated software by timely and disciplined utilization of failure and maintenance data to generate and implement effective corrective actions to prevent failure recurrence and to simplify or reduce the maintenance tasks. This process applies to acquisition for the design, development, fabrication, test, and operation of military systems, equipment, and associated computer programs. This paper shows the FRACAS development process and developed FRACAS system for a defense equipment.