• Title/Summary/Keyword: failure causes

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PROPOSING MANAGEMENT OF WORK PRIORITY TO REDUCE CONSTRUCTION FAILURE CLAIMS

  • In-ho Kim;Moon-Seo Park;Hyun-Soo Lee
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.1171-1176
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    • 2005
  • Dispute related to construction projects involving numerous persons is one of the biggest challenges faced by contractors today. It costs a substantial amount of money and time in resolving these kinds of claims. Recently, with the changes in the construction environment and thought of relation with owner, the number of construction claims has increased. But, a majority of these claims do not prevail, and in fact, frequently get dismissed in its entirety. The reasons for such dismissals include the ignorance about the claims, lack of clear and convincing evidence, and so on. But most of reasons are the claims are not managed well on construction process. This paper analyzes the failure causes by relying on past claim failure cases, and then drew works that have connection with failure causes through interview. It also presented importance degree of construction management works.

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Failure Cause Analysis of Pole Transformers (주상변압기 고장원인분석)

  • Jung, Jong-Wook;Lee, Byung-Sung;Lee, Jae-Bong;Joun, Jae-Keun;Kwak, Hee-Ro
    • Proceedings of the KIEE Conference
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    • 2002.07a
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    • pp.503-507
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    • 2002
  • This paper describes the symptoms with the failure causes of pole transformers analyzed at KEPCO branch offices' request in 2001, and ultimately aims for devising proper countermeasures against the failures. The failure causes are generally divided into problems in manufacturing, mounting and operating. The pole transformers encounter the failure with unique mechanisms. To verify the mechanisms to failures and help devise proper countermeasures, a flowchart is proposed based on the authors' experience and foreign case studies. The failure causes of pole transformers can be analyzed more exactly by using the flowchart.

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A Study on the Causes of Failure of the 'Failed' Modern Housing Projects ('실패한' 근대 집합주거의 실패요인에 관한 연구)

  • Sohn, Sei-Kwan
    • Journal of the Korean housing association
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    • v.24 no.6
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    • pp.151-161
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    • 2013
  • This research is an effort to clarify the causes associated with the 'failure' of public housing projects built in the 20th century. Two of the most brutal symbol of failure were selected: the Pruitt-Igoe built in St. Louis, U.S.A. and the Bijlmermeer in the south of Amsterdam, Netherlands. Many critics have attributed the problems of the selected housing projects to architectural failure, and proposed a series of new approaches to architectural design. The claim that many housing projects 'failed' because they were based on an agenda for social reform, derived from the ideas of the CIAM, presupposes that architects were in the position of authority over providing housing for the poor. This research tries to overturn the belief of architectural community which has placed the responsibility for the failure of public housing on designers. The sense of isolation and powerlessness felt by the residents, and the social problems attendant on those feelings, may be reinforced by design but is not caused by Modern Architecture. It should be stressed that the political-economic and social context is more significant than the architectural design for the failure of public housing projects such as the Pruitt-Igoe and the Bijlmermeer.

Failure Analysis to Derive the Causes of Abnormal Condition of Electric Locomotive Subsystem (센서 데이터를 이용한 전기 기관차의 이상 상태 요인분석)

  • So, Min-Seop;Jun, Hong-Bae;Shin, Jong-Ho
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.41 no.2
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    • pp.84-94
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    • 2018
  • In recent years, the diminishing of operation and maintenance cost using advanced maintenance technology is attracting many companies' attention. Especially, the heavy machinery industry regards it as a crucial problem since a failure of heavy machinery requires high cost and long downtime. To improve the current maintenance process, the heavy machinery industry tries to develop a methodology to predict failure in advance and to find its causes using usage data. A better analysis of failure causes requires more data so that various kinds of sensor are attached to machines and abundant amount of product usage data is collected through the sensor network. However, the systemic analysis of the collected product usage data is still in its infant stage. Many previous works have focused on failure occurrence as statistical data for reliability analysis. There have been less works to apply product usage data into root cause analysis of product failure. The product usage data collected while failures occur should be considered failure cause analysis. To do this, this study proposes a methodology to apply product usage data into failure cause analysis. The proposed methodology in this study is composed of several steps to transform product usage into failure causes. Various statistical analysis combined with product usage data such as multinomial logistic regression, T-test, and so on are used for the root cause analysis. The proposed methodology is applied to field data coming from operated locomotive and the analysis result shows its effectiveness.

An Economic Design of a k-out-of-n System

  • Yun, Won-Young;Kim, Gue-Rae;Gopi Chattopadhyay
    • International Journal of Reliability and Applications
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    • v.4 no.2
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    • pp.51-56
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    • 2003
  • A k-out-of-n system with n identical and independent components is considered in which the components takes two types of function: 0 (open-circuit) or 1 (closed) on command (e.g. electromagnetic relays and solid state switches). Components are subject to two types of failure on command: failure to close or failure to open. In our k-out-of-n system, failure of (n-k)+1 or more components to close causes to the close failure of the system, or failure of k or more components to open causes the open failure of the system. The long-run average cost rate is obtained. We find the optimal k minimizing the long run average cost rate for given n. A numerical example is presented.

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A Causal Analysis of Conglomerate Bankruptcies

  • KU, Sang-Wuk;WHANG, Yun-Oh
    • The Journal of Economics, Marketing and Management
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    • v.8 no.1
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    • pp.12-19
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    • 2020
  • Purpose - Strategic causes for the failure include unrealistic growth, overexpansion, unfamiliar new markets, volume obsession, unrealistic promises and poor project selection. Organizational causes are insufficient capital and profits, lack of business knowledge, poor financial management, poor sales skills, inadequate marketing, poor leadership, poor leadership transfer, project losses, poor field performance and owner bankruptcy. Uncontrollable causes include industry and economic weakness and banking and surety changes. While helpful, the list provides insufficient clarity regarding the causal roots of failure. Research design, data and methodology - The research framework to organize the information involved with many of the recent and large failures in the industry. Results - This research then identified five dominant root causes - excessive egoism, poor strategic leadership, too much change, loss of discipline and inadequate capitalization. Conclusion - Finally, additional input from external forces may accelerate the firm's pace to failure. It is important on the development of diagnostic tools that are based on this model and that will provide new ways to assess a conglomerate's level of risk for incurring a financial crisis.

Causes of Failure in the Radiation Therapy of Head and Neck Cancer - Clinico-Radiobiogical Correlations- (두경부암의 방사선치료에서 치료실패의 요인에 관한 분석 - 임상 및 방사선 생물학적 측면에서의 고찰 -)

  • Kim Gwi-E.
    • Korean Journal of Head & Neck Oncology
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    • v.6 no.1
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    • pp.1-10
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    • 1990
  • This review will be discussed the various causes of radiation failure for head and neck cancers from radiobiologic perspective and also provided a few clinical data to illustrate the basic principle. A knowledge about multiplicity of factors that may underlie failure of radiation treatment is essential for rational application of new treatment strategies. Furthermore, it is important to distinguish causes of failure that can be reduced or minimized by application of conventional treatment from one are potentially remediable by new treatment strategies, and one that are not amenable to some modification of radiotherapeutic approach.

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Risk Evaluation Based on the Hierarchical Time Delay Model in FMEA (FMEA에서 계층적 시간 지연 모형에 근거한 위험평가)

  • Jang, Hyeon Ae;Lee, Min Koo;Hong, Sung Hoon;Kwon, Hyuck Moo
    • Journal of Korean Society for Quality Management
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    • v.44 no.2
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    • pp.373-388
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    • 2016
  • Purpose: This paper suggests a hierarchical time delay model to evaluate failure risks in FMEA(failure modes and effects analysis). In place of the conventional RPN(risk priority number), a more reasonable and objective risk metric is proposed under hierarchical failure cause structure considering time delay between a failure mode and its causes. Methods: The structure of failure modes and their corresponding causes are analyzed together with the time gaps between occurrences of causes and failures. Assuming the severity of a failure depends on the length of the delayed time for corrective action, a severity model is developed. Using the expected severity, a risk priority metric is defined. Results: For linear and quadratic types of severity, nice forms of expected severity are derived and a meaningful metric for risk evaluation is defined. Conclusion: The suggested REM(risk evaluation metric) provides a more reasonable and objective risk measure than the conventional RPN for FMEA.

A Case Study on the Failure of Intake and Exhaust Valves for Marine Diesel Engines

  • Kim Jong-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.7
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    • pp.801-807
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    • 2005
  • Any failure of intake and exhaust valves of marine diesel engine must be regarded as serious, and any steps which can be taken to prevent such failure are desirable. The purposes of this study is to investigate and to analyse the failure causes of intake and exhaust valves for marine diesel engine during sea trial after completion of overhauling. In this study, to analyse the failure causes, we have carried out on board inspection, fractography test and discussion based on the specimen and repairing report provided by the ship owner. From the results of above inspection, test and discussion, it has been considered reasonable to conclude that the causes of damaged valves of the ship are as follow ; 1) During operation, the stick or seizure of valve spindle occurred and hence the movement of exhaust valve spindle was to be resisted and subsequently the engine was to be operated under an unappropriated valve timing and the exhaust valve sustained the repeated loads exceeding the fatigue strength of valve material. 2) By the loads above described, the fatigue fracture was initiated at the structural noncontinuous part of exhaust valve spindle, and then the valve head was finally fractured and dropped in the cylinder. 3) The fractured exhaust valve head impacted the intake valve at various direction to be bent or damaged.

A Study on the Causes of Steep Slope Failure induced Heavy Rainfall (집중호우시 급경사지 붕괴발생 원인분석 연구)

  • Ryu, Ji Hyeob;Lim, Ik Hyen;Hwang, Eui Jin
    • Journal of Korean Society of societal Security
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    • v.4 no.1
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    • pp.67-74
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    • 2011
  • This paper was to examine the causes of steep slope failure during the season of heavy rainfall. For the purpose, the paper carefully analyzed the sites of steep slope failure, which happened in July 2009. The direct cause of steep slope failure was much related to heavy rainfall during summer. The paper continued to verify that additional causes include the malfunction of diverse waterways, the slope design without considering weathering soils and related characteristics, the lack of the waterway size, the intrusion of plant roots, the reinforced technique without considering slope conditions, etc.

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