• Title/Summary/Keyword: failure causes

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Clinical Manifestation of Children with Failure to Thrive (Failure to Thrive를 주소로 내원한 환아들의 임상상)

  • Moon, Jeong-Hee;Kim, Ji-Young;Beck, Nam-Sun
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.3 no.1
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    • pp.68-74
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    • 2000
  • Purpose: This study was to investigate the clinical manifestations of FTT in children. Methods: From March 1997 to July 1999, clinical observations were made on patients with FTT who had visited to Samsung Medical Center. Detailed histories and through physical examinations were taken, and when suspected organic FTT, basic laboratory studies were done. Results: Upon the review of medical records, we investigated the clinical manifestations of 74 children, aged 1 month and 13 year 1 month. The causes of FTT were composed of either physiologic (47.8%) or pathologic (52.2%) ones. Among the physiologic FTT, were there familial short stature (FSS, 14.5%), intrauterine growth retardation (IUGR, 14.5%), constitutional growth delay (CGD, 11.6%), idiosyncrasy and prematurity. Among pathologic causes, neurologic disorders (20%) are the most common causes of FTT, and then follow by GI (13.4%), allergic and infectious disorders in decreasing order. The data showed that average caloric intake in patients with FTT was 76,2% of recommended amount. FTT patients with CGD, IUGR, and idiosyncrasy had tendency to take small foods. The FTT children with prematurity, IUGR and pathologic FTT, were short and thin for their ages. However FTT children with CGD and FSS had tendency to be thin with relatively normal heights for their ages, in comparison with those of the children with prematurity, IUGR and pathologic FTT. Conclusion: The diagnosis of FTT was easily obtained with simple and through medical history, physical examination, and minimal laboratory tests. In this study, organic FTT was more prevalent than physiologic one. This results indicate that early intervention is mandatory, because children may develop significant long-term sequelae from nutritional deficiency.

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An Analysis of the Accident Types and Causes of Construction Cranes (크레인 관련 중대재해사례를 통한 재해 유형 및 원인 분석)

  • Kim, Hong-Hyun;Lee, Ghang
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2007.04a
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    • pp.109-112
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    • 2007
  • As buildings become higher, larger, and more complex, safety issues for construction workers working at such environments become more important. We analyzed 140 critical accident cases reported to the KOSHA(Korea Occupational Safety & Health Agency) for construction cranes and lifts by types of cranes and by patterns of accidents and causes. By finding out the accident's types and causes, we expect to develop an efficient measure for preventing similar accidents in the near future. The cases will be studied further and reexamined using the FMEA(Failure Mode and Effect Analysis) as a quantitative analysis method.

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Effects of Web Reinforcement Amount on Hysteretic Behavior of High Strength Reinforced Concrete Structural Walls (전단보강근비에 따른 고강도 철근콘크리트 내력벽의 이력특성)

  • 최근도;정학영;윤현도;최장식;이리형
    • Proceedings of the Korea Concrete Institute Conference
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    • 1994.04a
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    • pp.85-90
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    • 1994
  • Three high strength reinforced concrete structural walls were tested under the combined action of a constant axial and a horizontal cycle load. The aim of the tests has been to investigate the effects of the web horizontal reinforcement on hysteretic behavior of wall. The results have helped to identify the causes of wall failure and have demonstrated the web horizontal reinforcement does not appear have a significant effect on shear capacity, stiffness and energy dissipation but have a significant effect on the failure mode of the walls.

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Damages of the Sliding Surface in Fluid Film Bearings (유체 윤활 미끄럼 베어링의 표면 손상)

  • 하현천;방경보;박영철;김일봉
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1998.10a
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    • pp.196-202
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    • 1998
  • Because the journal and bearing surface are fully separated by the oil film during the normal operation, fluid film bearings operating in the hydrodynamic lubrication region are expected to have an infinite life. However, there are many parameters that lead to interfere with the normal operation of the bearing and lead to its failure. In this paper, both the causes and countermeasures of the bearing failure are described. Also, the characteristics of wiped bearing surface are investigated through mechanical and chemical test.

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Design Study of Adhesively Bonded Structures

  • Chung, Jae-Ung
    • Korean Journal of Computational Design and Engineering
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    • v.14 no.2
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    • pp.122-128
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    • 2009
  • The failure responses of adhesively bonded, hat stiffened structures are studied through numerical analysis using the finite element method. The responses are evaluated numerically for the bonded hat section/substrate structures containing different combinations of materials. It is studied what kind of material combinations causes the easier crack initiation in the structure. This study is conducted under plane strain conditions and J-integral via a commercial code ABAQUS as a total critical energy release criterion was used for observation on crack initiation. Also, the influence of adhesive on the structure is studied.

A study on Optimum Inspection Policy for an equipment with two stages of failures (이단계 고장을 갖는 설비에 대한 최적 검사 정책)

  • 김정식
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.13 no.21
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    • pp.19-24
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    • 1990
  • This paper deals with a problem of choosing an optimum inspection period for an equipment with two stages of failures. Stage I failure which can be detected only through inspection detenorates the equipment and causes critical stage II failure after a random period of time. The expected average cost function is obtained and an optimum inspection policy is discussed. A numerical example is also worked out.

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The effects of Joint Stiffness On Concrete Pavements (콘크리트 포장구조에서 조인트 강성의 영향)

  • 조병완
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1990.04a
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    • pp.50-52
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    • 1990
  • Although concrete pavements were successfully widespread throughout the nation due to the desirable surface characteristics, durability, and economy, it still causes several transverse cracking and joint failure problems in some areas. In this paper, the major emphasis was given to provide a rational analytical approach on joint failure mechanisms, considering several sets of joint stiffnesses on different subgrade moduli. Besides , load transfer mechanisms on concrete pavement joints were highlighted with finite element method and computer modeling.

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Components of a Comprehensive Transformer Monitoring and Diagnostic System (새로운 방식의 변압기)

  • Kim, Hyung-Seung;Kane, Claude
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.97-98
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    • 2007
  • A wide range of data is available as too causes of large power transformers. Although the percentage of transformer component failure rates vary, all data shows that the top three failure mechanisms are Load Tap Changers (LTC), Bushings and Windings. To date, the most common methods employed to determine the health of a transformer are off line tests and online temperature monitoring, winding hotspot calculations and dissolved gas analysis.

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Analysis of Orthotropic Bearing Non-linearity Using Non-linear FRFs

  • Han Dong-Ju
    • Journal of Mechanical Science and Technology
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    • v.20 no.2
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    • pp.205-211
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    • 2006
  • Among other critical conditions in rotor systems the large non-linear vibration excited by bearing non-linearity causes the rotor failure. For reducing this catastrophic failure and predictive detection of this phenomenon the analysis of orthotropic bearing non-linearity in rotor system using higher order frequency response functions (HFRFs) is conducted and is shown to be theoretically feasible as that of non-rotating structures. The complex HFRFs based on the Volterra series are newly developed for the process and investigated their features by using the simple forms of the FRFs associated with the forward and the backward modes.

Automatic classify of failure patterns in semiconductor fabrication for yield improvement (수율 향상을 위한 반도체 공정에서의 불량 유형 자동 분류)

  • 한영신;최성윤;김상진;황미영;이칠기
    • Proceedings of the Korea Society for Simulation Conference
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    • 2003.11a
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    • pp.147-151
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    • 2003
  • Yield enhancement in semiconductor fabrication is important. Even though DRAM yield loss may be attributed to many problems, the existence of defects on the wafer is one of the main causes. When the defects on the wafer form patterns, it is usually an indication for the identification of equipment problems or process variations. In this paper describes the techniques to automatically classify a failure pattern using a fail bit map.

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