• 제목/요약/키워드: failure causes

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선박용 디젤기관의 피스톤 파손사고에 대한 연구 (A Case Study on the Failure of Piston for Marine Diesel Engine)

  • 김종호
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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    • pp.222-223
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    • 2005
  • The Any failure of piston 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 piston of marine diesel engine. If this paper has accomplished that end it can be counted as being of some slight value to the marine industry.

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소아의 급성 신부전증 (Acute renal failure in pediatrics)

  • 한혜원
    • Clinical and Experimental Pediatrics
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    • 제50권10호
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    • pp.948-953
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    • 2007
  • Acute renal failure is the generic term for an abrupt and sustained decrease in renal function resulting in retention of nitrogenous and non nitrogenous waste product. This may results in life threatening consequences including volume overload, hyperkalemia, and metabolic acidosis. Acute renal failure is both common and carries high mortality rate, but as it is often preventable, identification of patients at risk and and appropriate management are crucial. This review summarized the most recent information on definition, epidemiology, clinical causes and management of acute renal failure in pediatric patients.

THE CAUSES OF BAD PROFIT IN OVERSEAS CONSTRUCTION PROJECTS

  • Seung Heon Han;Du Yon Kim;Sang Hyuk Park
    • 국제학술발표논문집
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    • The 1th International Conference on Construction Engineering and Project Management
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    • pp.1237-1243
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    • 2005
  • International construction projects are exposed to various and complicated risk factors stemming from different political, economical, social, and cultural backgrounds, which make contractors entering into international construction to experience severe losses. It implies that overseas markets do not necessarily secure the high return, which is typically expected to in the high risky attempts. Accordingly, contractors need to evaluate various risk factors faced with overseas construction projects that can possibly aggravate the profitability. This paper aims at establishing a valid groundwork for further research on developing the integrated risk management model. For this end, it analyzes the long-term trend of profitability on total of 3,487 projects performed by Korean global contractors in world-wide construction markets during the last four decades. Then, it investigates the possible factors/causes of bad profit that have affected the profitability significantly through the structured surveys of 90 real overseas projects based on the project-specific information and experiences of Korean contractors in overseas markets. Furthermore, it analyzes relative importance of these factors/causes and identifies the important features expected for the risk management of international construction projects. Finally, vital distinctions between success and failure projects and lessons learned to improve profitability are then distilled.

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대규모 사면의 붕괴사례 (Case Study on Large Cutting Slope Failure)

  • 박영목
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2002년도 가을 학술발표회 논문집
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    • pp.27-43
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    • 2002
  • This paper described two case studies on large scale failure of cutting slope. The kind of rock in both sites predominated limestone and shale respectively. These cutting slopes located in northern area of Gyongbug Province are composed of very complicated and various rock mass. Geological characteristics, causes of failure, proceeding of security diagnose, maintenance method etc. of two sites were carried out to check the cutting slope stability and to provide reasonable maintenance method. This paper may provide the useful data for engineers related with design and construction of large cutting slope.

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Fatal progressive right heart failure in a pancreatic cancer patient

  • Byoun, Jeong Tae;Cho, Jae Young
    • Journal of Yeungnam Medical Science
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    • 제37권2호
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    • pp.122-127
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    • 2020
  • Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare but fatal complication of cancer and causes pulmonary hypertension and acute/subacute right heart failure. PTTM is most commonly associated with gastric cancer and more rarely associated with pancreatic cancer. We report a case of progressive right heart failure associated with clinically diagnosed pancreatic cancer, suggesting PTTM.

FMEA에서 고장발생 및 탐지시간을 고려한 고장원인의 위험평가 척도 (A Risk Metric for Failure Cause in FMEA under Time-Dependent Failure Occurrence and Detection)

  • 권혁무;홍성훈;이민구
    • 품질경영학회지
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    • 제47권3호
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    • pp.571-582
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    • 2019
  • Purpose: To develop a risk metric for failure cause that can help determine the action priority of each failure cause in FMEA considering time sequence of cause- failure- detection. Methods: Assuming a quadratic loss function the unfulfilled mission period, a risk metric is obtained by deriving the failure time distribution. Results: The proposed risk metric has some reasonable properties for evaluating risk accompanied with a failure cause. Conclusion: The study may be applied to determining action priorities among all the failure causes in the FMEA sheet, requiring further studies for general situation of failure process.

Clinical performance and failures of zirconia-based fixed partial dentures: a review literature

  • Triwatana, Premwara;Nagaviroj, Noppavan;Tulapornchai, Chantana
    • The Journal of Advanced Prosthodontics
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    • 제4권2호
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    • pp.76-83
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    • 2012
  • PURPOSE. Zirconia has been used in clinical dentistry for approximately a decade, and there have been several reports regarding the clinical performance and survival rates of zirconia-based restorations. The aim of this article was to review the literatures published from 2000 to 2010 regarding the clinical performance and the causes of failure of zirconia fixed partial dentures (FPDs). MATERIALS AND METHODS. An electronic search of English peer-reviewed dental literatures was performed through PubMed to obtain all the clinical studies focused on the performance of the zirconia FPDs. The electronic search was supplemented by manual searching through the references of the selected articles for possible inclusion of some articles. Randomized controlled clinical trials, longitudinal prospective and retrospective cohort studies were the focuses of this review. Articles that did not focus on the restoration of teeth using zirconia-based restorations were excluded from this review. RESULTS. There have been three studies for the study of zirconia single crowns. The clinical outcome was satisfactory (acceptable) according to the CDA evaluation. There have been 14 studies for the study of zirconia FPDs. The survival rates of zirconia anterior and posterior FPDs ranged between 73.9% - 100% after 2 - 5 years. The causes of failure were veneer fracture, ceramic core fracture, abutment tooth fracture, secondary caries, and restoration dislodgment. CONCLUSION. The overall performance of zirconia FPDs was satisfactory according to either USPHS criteria or CDA evaluations. Fracture resistance of core and veneering ceramics, bonding between core and veneering materials, and marginal discrepancy of zirconia-based restorations were discussed as the causes of failure. Because of its repeated occurrence in many studies, future researches are essentially required to clarify this problem and to reduce the fracture incident.

What Causes Technology Commercialization to Succeed or Fail after Transfer from Public Research Organizations

  • Kim, Yong-Jeong;Shin, Seowon Joseph
    • Asian Journal of Innovation and Policy
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    • 제6권1호
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    • pp.23-44
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    • 2017
  • This study explores how the technology commercialization process leads to either success or failure after transfer from PROs to SMEs by conducting a binomial logistic regression analysis. We found that the more additional development a firm implements on the transferred technology, the more likely the commercialization is to fail. The higher number of alternative technology and bigger market risk are associated with a greater likelihood of failure. On the other hand, the existence of complementary technology, the degree of cooperation with the technology provider, the size of the target market, the willingness of the CEO, and the funding availability are known to have positive effects on the success of technology commercialization. In addition, the case studies we conducted from the sample companies demonstrated that "market uncertainty," "technological issues depending on the technology-specific characteristics," and "a lack of funding capability" are some of the causes for failure of technology commercialization.

서울메트로 전력케이블 장애현황 분석 (Seoulmetro Power Cable's Obstacle situation analysis)

  • 위삼복;정노건;김재문;김양수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2015년도 제46회 하계학술대회
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    • pp.1611-1612
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    • 2015
  • This research paper is to analyze the specific situation for the 157 failure cases of Seoul Metro power cable since 1990 and to consider the countermeasures. This is, also, to prevent accidents by analyzing the current state of each Line, the failure of causes, railroad tracks, installation year, opening year, and monthly failure conditions and by presenting the countermeasures. In addition, this research is to discuss the present installation situation of Seoul Metro power cable, the types of power cable, symptoms, causes and the countermeasures.

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ESD에 의한 반도체소자의 손상특성 (Damage and Failure Characteristics of Semiconductor Devices by ESD)

  • 김두현;김상렬
    • 한국안전학회지
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    • 제15권4호
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    • pp.62-68
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    • 2000
  • Static electricity in electronics manufacturing plants causes the economic loss, yet it is one of the least understood and least recognized effects haunting the industry today. Today's challenge in semiconductor devices is to achieve greater functional density pattern and to miniaturize electronic systems of being more fragile by electrostatic discharges(ESD) phenomena. As the use of automatic handling equipment for static-sensitive semiconductor components is rapidly increased, most manufacturers need to be more alert to the problem of ESD. One of the most common causes of electrostatic damage is the direct transfer of electrostatic charge from the human body or a charged material to the static-sensitive devices. To evaluate the ESD hazards by charged human body and devices, in this paper, characteristics of electrostatic attenuation in domestic semiconductor devices is investigated and the voltage to cause electronic component failures is investigated by field-induced charged device model(FCDM) tester. The FCDM simulator provides a fast and inexpensive test that faithfully represents ESD hazards in plants. Also the results obtained in this paper can be used for the prevention of semiconductor failure from ESD hazards.

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