• 제목/요약/키워드: failure site

검색결과 770건 처리시간 0.032초

과지압 암반 내 대규모 지하 유류비축기지 안정성 평가 및 Microseismic 계측 (Stability evaluation and microseismic monitoring around Large Underground Oil Storage Cavern in Over-stressed Rock Mass)

  • 이희석;이대혁;김호영;홍지수;최영태;김석진;박연준
    • 한국터널공학회:학술대회논문집
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    • 한국터널공학회 2005년도 학술발표회 논문집
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    • pp.189-201
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    • 2005
  • Brittle failure has been detected in over-stressed rock mass during the construction of oil storage cavern. The main characteristics of stress induced brittle failure of the site are introduced. Various evaluation and measures are sought to stabilize the over-stressed rock mass. The major results from numerical analysis of the cavern are presented, and from current microseismic monitoring to detect hazard from brittle failure are presented.

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Contractors' Perception towards Safety and its Consequences on Construction Workers in Cape Coast Metropolis

  • Mustapha, Zakari
    • 식품보건융합연구
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    • 제5권6호
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    • pp.11-16
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    • 2019
  • The construction environment has been declared as a hazard prone area due to high number of accident and death. The study aims to identify influential factors that contribute to poor safety practices and its consequences on construction workers in Cape Coast Metropolis. Seventy respondents were taken as the sample size for the study. Descriptive analysis was used to analyze the data obtained from the field. Findings show that poor site management, working without safety gadgets, failure to use their Personal Protective Equipment (PPE) and negligence of workers were the main causes of accidents on sites. Poor site management had the highest ranking among the seven variables. Effects of poor safety practices on building construction site and delays in work execution were due to injury of workers, extra cost due to payment of compensation to injured victims, not motivated due to injury of worker and declined reputation of firm. Management team should motivate workers for safe work done, provide adequate PPE for their workers on site and have documented health and safety policy on site. Site authorities and management team should be on site regularly to ensure proper safety practices on construction site.

화강암-안산암 접촉부 대규모 사면의 붕괴 사례 연구 (A case study of large-scale slope failure in Granite - Andesite contact area)

  • 이수곤;양홍석;황의성
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.503-508
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    • 2003
  • In this study, we peformed ahead a field geological investigation, boring investigation for slope stability analysis in large scale slope failure area. But the geological stratum was not clearly grasped, because ground was very disturbed by large scale Granite intrusion. Furthermore, the existing test data was not pertinent to the large scale Granite intrusion site like here. Therefore, various kind of field test were performed to grasp clearly for geological stratum. And the results of back analysis, various kind tests used to slope stability analysis.

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전력산업에서의 품질경영활동의 평가척도 (Assessment of Quality Management Activities in Power Industries)

  • 정영배
    • 산업경영시스템학회지
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    • 제24권63호
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    • pp.89-99
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    • 2001
  • This paper proposes assessment of quality management activities based on cost of quality. Cost of quality is considered prevention cost, appraisal cost, internal failure cost, external failure cost in this paper. This paper shows quality cost magement system in thermal power site devision according to activity analysis. Cost of quality in power industries provides a valuable method of both proving the need for improvement and giving a starting point for projects.

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Shaking table test on seismic response and failure characteristics of ground fissures site during earthquakes

  • Chao, Zhang;Xuzhi, Nie;Zhongming, Xiong;Yuekui, Pang;Xiaolu, Yuan;Yan, Zhuge;Youjun, Xu
    • Geomechanics and Engineering
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    • 제32권3호
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    • pp.307-319
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    • 2023
  • Ground fissures have a huge effect on the integrity of surface structures. In high-intensity ground fissure regions, however, land resource would be wasted and city building and economic development would be limited if the area avoiding principle was used. In view of this challenge, to reveal the seismic response and seismic failure characteristics of ground fissure sites, a shaking table test on model soil based on a 1:15 scale experiment was carried out. In the test, the spatial distribution characteristics of acceleration response and Arias intensity were obtained for a site exposed to earthquakes with different characteristics. Furthermore, the failure characteristics and damage evolution of the model soil were analyzed. The test results indicated that, with the increase in the earthquake acceleration magnitude, the crack width of the ground fissure enlarged from 0 to 5 mm. The soil of the hanging wall was characterized by earlier cracking and a higher abundance of secondary fissures at 45°. Under strong earthquakes, the model soil, especially the soil near the ground fissure, was severely damaged and exhibited reduced stiffness. As a result, its natural frequency also decreased from 11.41 Hz to 8.05 Hz, whereas the damping ratio increased from 4.8% to 9.1%. Due to the existence of ground fissure, the acceleration was amplified to nearly 0.476 m/s2, as high as 2.38 times of the input acceleration magnitude. The maximum of acceleration and Arias intensity appeared at the fissure zone, which decreased from the main fissure toward both sides, showing hanging wall effects. The seismic intensity, duration and frequency spectrum all had certain effects on the seismic response of the ground fissure site, but their influence degrees were different. The seismic response of the site induced by the seismic wave that had richer low-frequency components and longer duration was larger. The discrepancies of seismic response between the hanging wall and the footwall declined obviously when the magnitude of the earthquake acceleration increased. The research results will be propitious to enhancing the utilizing ratio of the limited landing resource, alleviation of property damages and casualties, and provide a good engineering application foreground.

FMEA 기법을 활용한 공동주택 골조공사의 건설실패 핵심관리요인 분석 (An Analysis of Critical Management Factors for Construction Failure on the Apartment Structural Framework using FMEA)

  • 오치돈;박찬식
    • 한국건설관리학회논문집
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    • 제13권3호
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    • pp.78-88
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    • 2012
  • 국내의 건설실패 관련 연구는 체계화된 실패정보 분류체계 및 실패정보의 활용을 위한 방안을 제시하는 것에 초점을 맞추고 있다. 그러나, 건설현장의 한정된 관리자가 건설실패를 유발하는 다양한 원인에 대한 예방대책을 수립하는 것은 한계가 있다. 따라서, 효율적인 건설실패 예방활동이 이루지기 위해서는 많은 실패원인에 대한 정량적 평가를 통해 우선순위를 정하여 효율적인 예방대책이 수립되어야 한다. 이에 본 연구는 정량적인 평가를 통해 실패를 유발하는 핵심관리요인을 도출 할 수 있도록 FMEA(Failure Mode and Effect Analysis) 기법을 활용한 건설실패 핵심관리요인 선정방법을 제시하고, 공동주택 골조공사를 대상으로 핵심관리요인을 분석하는 것을 목적으로 하였다. 이를 위해 FMEA 기법의 위험도를 실패 위험성과 예방성으로 구분하여 평가할 수 있도록 하였다. 본 연구에서 제시한 핵심관리요인 평가방법은 건설실패의 사전예방대책을 효율적으로 수립하는데 활용될 수 있으며, 향후 유사한 연구를 통해 프로젝트 수행 단계별 혹은 다양한 시설 및 공종에 대한 핵심관리요인을 도출하는데 활용될 수 있을 것으로 기대된다.

경비기관 내 삽관 시 좌 우측 비공 선택에서 비출혈 및 튜브 진입 실패 빈도에 관한 연구 (The Clinical Study for Epistaxis and Tube Insertion Failure Incidence on the Choice of Nostril during Nasotracheal Intubation)

  • 서광석;주리아;고승지;김현정;염광원
    • 대한치과마취과학회지
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    • 제5권2호
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    • pp.107-111
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    • 2005
  • Background: Nasotracheal intubation for general anesthesia is preferred for many oral and maxillofacial procedures because it ensures unhindered access to the operative site. Epistaxis and tube insertion failures are recognized complications of nasotracheal intubation. The aim of our study was to elucidate whether the nostril side used influenced epistaxis and insertion failure incidence. Methods: We studied 434 patients undergoing nasal intubation (July 2004- February 2005) with permission. Randomly, one side of nostril was selected with chart ID number. During nasotracheal intubation, epistaxis severity and tube insertion failure was observed by the anesthesiologist who inserted nasotracheal tube. Results: There was no significant difference between either nostril in epistaxis severity (chi-square test P = 0.860) and in the incidence of insertion failure (P = 0.867). Conclusions: In this study, both nostrils showed equal epistaxis and insertion failure incidence.

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계단식 보강토옹벽의 파괴 메카니즘 연구 (Failure Mechanism of Geosynthetic-Reinforced Segmental Retaining Wall in a Tiered Configuration)

  • 유충식;정혁상;이봉원
    • 한국지반신소재학회논문집
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    • 제3권4호
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    • pp.13-19
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    • 2004
  • 본 연구에서는 계단식 보강토 옹벽의 파괴메카니즘 연구를 위해 모형실험을 실시한 내용을 다루었다. 보강토옹벽의 모형실험은 성균관대학교 내의 지반시험장에 시험 시공한 계단식보강토옹벽의 원형을 축소하여 모사하였으며, 상사법칙을 이용하여 보강통옹벽에 사용된 재료의 크기 및 물성치를 원형에 가깝도록 축소하여 파괴메카니즘 분석에 신뢰성을 높였다. 또한 파괴메카니즘 분석을 위해 종전의 재하실험 방식과는 달리 자중에 의한 파괴가 가능해짐으로써 원형에 가까운 파괴 형상을 모사 할 수 있었다. 모형 실험의 내용으로는 보강토옹벽의 영향인자라고 할 수 있는 이격거리의 변화 및 보강재 길이변화에 따른 파괴 양상을 분석하였다.

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A numerical approach for assessing internal pressure capacity at liner failure in the expanded free-field of the prestressed concrete containment vessel

  • Woo-Min Cho;Seong-Kug Ha;SaeHanSol Kang;Yoon-Suk Chang
    • Nuclear Engineering and Technology
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    • 제55권10호
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    • pp.3677-3691
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    • 2023
  • Since containment building is the major shielding structure to ensure safety of nuclear power plant, the structural behavior and ultimate pressure capacity of containments must be studied in depth. This paper addresses ambiguous issue of determining free-field position for liner failure by suggesting an expanded free-field region and comparing internal pressure capacities obtained by test data, conservative assumption and suggested free-field region. For this purpose, a practical approach to determine the free-field position for the evaluation of liner tearing is carried out. The maximum principal strain histories versus internal pressure capacities among different free-field positions at various azimuths and elevations are compared with those at the equipment hatch as a conservative assumption. The comparison shows that there are considerable differences in the internal pressure capacity at liner failure within the expanded free-field region compared to the vicinity of the equipment hatch. Additionally, this study proposes an approximate correlation with conservative factors by considering the expanded free-field ranges and material characteristics to determine realistic failure criteria for liner. The applicability of the proposed correlation is demonstrated by comparing the internal pressure capacities of full-scale containment buildings following liner failure criteria according to RG 1.216 and an approximate correlation.

디지털콘텐츠 유통 웹사이트의 성공요인(에 관한 연구) (Success Factors of Digital Contents Distribution Websites)

  • 최용석;권혁인
    • Journal of Information Technology Applications and Management
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    • 제13권4호
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    • pp.215-235
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    • 2006
  • Recently, Development of IT and digital-tech, and this is becoming factor of digital contents industry development. But, problem that is more suitable e-business model's necessity and quality enemy of distribution web-site to digital contents as transaction this firm dispute by transaction special quality and Payment-system increase of digital contents increases rapidly was risen. In this study, Digital Contents qualify estimation very important persons of digital contents as sequence of study that investigate from target's viewpoint which is serviced through web-site that digital contents is not factors of web-site service method whether digital contents distribution web-site factors effect that is some in customer satisfaction from general viewpoint of actuality digital contents distribution and is the actual proof enemy. This paper's goal that these study finding leads as digital contents industry discusses individual enterprise's success and failure as field of business in quickening period yet but domestic digital contents industry field will be roared and may can have competitive power by enterprises which wish to already started business or inaugurate an enterprise enter in field with successful beginning and direction and develop continuously.

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