• 제목/요약/키워드: Factors of failure

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자갈질 재료의 비선형적 전단강도 특성 평가법 (Evaluation Method for Non-linear Shear Strength of Gravel Materials)

  • 신동훈;조성은;임은상;박한규
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.288-298
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    • 2009
  • It is well known that the peak strength envelope of geomaterials with no cohesion, such as sand, gravel and rockfill, exhibits significant curvature over a range of stresses. In a practical design of slope, however, the linear Mohr-Coulomb's failure envelope is used as a failure criterion and consequently gives inaccurate safety factors, especially for some ranges of small normal stresses on shallow failure surfaces. Necessity of a nonlinear shear strength envelope in slope stability analysis is on this point. Hence, this study describes how to evaluate nonlinear shear strength of gravel fill materials using the results of large triaxial tests under consolidated-drained condition, and compares the safety factors from slope stability analyses for a homogeneous gravel fill or rockfill embankment incorporating the non-linearity of strength, so as to show its effects on safety factors.

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패밀리레스토랑과 이동통신서비스의 서비스회복 결정요인 (The Factors for Service Recovery of Family Restaurant and Mobile Telecommunication Service)

  • 오세구
    • 품질경영학회지
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    • 제35권4호
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    • pp.111-122
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    • 2007
  • The purpose of the study is to find out the influences of various efforts on service recovery after the failure of the service for the customer satisfaction and a loyalty. The present study finds out the factors directly affecting service recovery and demonstrates the relationship of those factors with customer satisfaction and loyalty. As a result, the important factors for service recovery are an immediate compensation, truthfulness, reaction and assurance

심부전 환자의 기능상태에 영향을 미치는 요인 (Factors Influencing Functional Status in Patients with Heart Failure)

  • 송은경;김조자;유일영;김기연;김주형;하종원
    • 대한간호학회지
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    • 제36권5호
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    • pp.853-862
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    • 2006
  • Purpose: The purpose of this study was to identify the factors that influence the functional status of patients with heart failure. Method: A descriptive, correlational study design was used. The participants in this study were 260 patients with heart failure who were admitted at Y University and U University in Seoul, Korea. Between September 2005 and December 2005 data was collected by an interview using a questionnaire and from medical records. The Functional status was measured with KASI. Physical factors (dyspnea, ankle edema, chest pain, fatigue, and sleep dysfunction), psychological factors (anxiety and depression), and situational factors (self-management compliance and family support) were examined. Result: In general, the functional status, anxiety, depression, self-management compliance, and family support was relatively not good. The level of fatigue was highest and the level of ankle edema was lowest for physical symptom experiences. In regression analysis, functional status was significantly influenced by dyspnea(23%), age(13%), monthly income(7%), fatigue(3%), ankle edema(2%), depression(1%), and length of stay in the hospital(1%). These factors explained 50% of the variables in the functional status. Conclusion: These results suggest that psycho-physiological symptoms management should be a focus to improve the functional status in patients with heart failure.

가혹환경 하에서 사용되는 시스템의 외부환경보수에 대한 고장률 모형 (Failure Rate Model of External Environment Maintenance for a System under Severe Environment)

  • 박종훈;신윤제;이상천;이창훈
    • 대한산업공학회지
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    • 제36권1호
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    • pp.69-77
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    • 2010
  • The failure rate model of External Environment Maintenance(EEM) for a system under severe environment is investigated. EEM, which is recently introduced concept, is a maintenance activity controlling external environment factors that potentially cause system failure such as cleaning equipment, controlling temperature (humidity) and removing dust inside of electronic appliances. EEM can not have any influence on the inherent failure rate of a system but reduce the severity of the external environment causing failure since it deals with only external environment factors. Therefore, we propose two failure rate models to express the improvement effect of EEM: The intensity reduction model and age reduction model. The intensity and age reduction models of EEM are developed assuming the quality of improvement effect is proportioned to an extra intensity or age respectively. The validation of proposed failure rate models is performed in order of data generation, parameter estimation and test for goodness-of-fit.

제품속성별 신제품개발의 성패구조 분석모형 (Analytic Model on the Success/Failure Structure of New Product Development by Product Characteristic Grill)

  • 권철신;이재하
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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    • pp.205-211
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    • 2002
  • The purpose of this paper is 1) to extract managerial factor into each cell which is classified by the characteristic grill of new products 2) to construct a management model of new product development for korean companies. For this purpose, the characteristic grill of new products is classified by which is market/technology sphere. Moreover the focus of this analysis is on examination of success/failure factors, which have an important effect upon new product success or failure. The variables for this study were selected from literature survey and pre-interview was implemented specially. The subject of study was project leaders of electronics industry where have taken the leading part in product development activities in Korean manufacturing industries. Enquete survey was conducted in each firm and project managers were asked to respond. Conclusion of this study based on many significant results gained by the various multi-variate analysis are summarized as follows. First, it can he noted that success/failure factors are different by each classified model and characteristic grill of a new product. Second, it has been identified that the important factors of success products were technical & management support and market ability, the important factor of failure product were lacking in ability of technical development and R&D management system construction. This paper presents some useful guidelines in strategic and managerial aspects for development of new products. Concurrently, the model of this study should be a great practical approach for application of actual affairs.

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오류유형 영향분석(FMEA)을 적용한 수술준비 위험예방활동의 효과 (A Study on Failure Mode and Effect Analysis (FMEA) for Preoperative Risk Prevention)

  • 김창희;이미향
    • 간호행정학회지
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    • 제22권5호
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    • pp.415-423
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    • 2016
  • Purpose: The purpose of this research was to provide patients with safe preoperative preparatory procedures by removing any risk factors from the preparatory procedures by using failure mode and effects analysis, which is a prospective risk-managing tool. Methods: This was a research design in which before and after conditions of a single group were studied, Failure mode and effects analysis were applied for the preparatory procedures done before operations. Results: The preparation omission rate before the operation decreased from 2.70% to 0.04%, and operation cancellation rate decreased from 0.48% to 0.08%. Conclusion: Failure mode and effects analysis which remove any risk factors for patients in advance of the operation is effective in preventing any negligent accidents.

일반병동 입원환자의 어려운 기도 예측 여부에 따른 기관 내 삽관의 결과 분석 (Outcome Analysis of Endotracheal Intubation for General Ward Patients with and without Predicted Difficulty)

  • 안지영;최혜란
    • 중환자간호학회지
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    • 제7권2호
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    • pp.34-44
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    • 2014
  • Purpose: The purpose of this study was to determine the factors related to airway failure during endotracheal intubation among patients with and without predicted airway difficulty. Methods: Medical records were examined retrospectively. 329 patients who were admitted to the general ward and underwent endotracheal intubation were included. The incidence of airway failure in the two groups was investigated. Results: The group predicted to have airway difficulty consisted of 79 patients (24.0%) and the group without airway difficulty, 250 (76.0%). The number of cases of airway failure was 50 (15.2%). The factors that were associated with airway failure in the group with predicted airway difficulty were the jaw relaxation score, Cormack-Lehane score, and the device of the first endotracheal intubation attempt. The factors that were associated with the airway failure in the group predicted not to have airway difficulty were the induction agent, jaw relaxation score, Cormack-Lehane score, level of training of the personnel with the first endotracheal intubation success, and the device of the first endotracheal intubation attempt. Conclusion: The prediction of airway difficulty during endotracheal intubation was not effective; however, it was meaningful from the perspective of patient safety.

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Risk factors for anticoagulant-associated gastrointestinal hemorrhage: a systematic review and meta-analysis

  • Fuxin Ma;Shuyi Wu;Shiqi Li;Zhiwei Zeng;Jinhua Zhang
    • The Korean journal of internal medicine
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    • 제39권1호
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    • pp.77-85
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    • 2024
  • Background/Aims: There may be many predictors of anticoagulation-related gastrointestinal bleeding (GIB), but until now, systematic reviews and assessments of the certainty of the evidence have not been published. We conducted a systematic review to identify all risk factors for anticoagulant-associated GIB to inform risk prediction in the management of anticoagulation-related GIB. Methods: A systematic review and meta-analysis were conducted to search PubMed, EMBASE, Web of Science, and Cochrane Library databases (from inception through January 21, 2022) using the following search terms: anticoagulants, heparin, warfarin, dabigatran, rivaroxaban, apixaban, DOACs, gastrointestinal hemorrhage, risk factors. According to inclusion and exclusion criteria, studies of risk factors for anticoagulation-related GIB were identified. Risk factors for anticoagulant-associated GIB were used as the outcome index of this review. Results: We included 34 studies in our analysis. For anticoagulant-associated GIB, moderate-certainty evidence showed a probable association with older age, kidney disease, concomitant use of aspirin, concomitant use of the antiplatelet agent, heart failure, myocardial infarction, hematochezia, renal failure, coronary artery disease, helicobacter pylori infection, social risk factors, alcohol use, smoking, anemia, history of sleep apnea, chronic obstructive pulmonary disease, international normalized ratio (INR), obesity et al. Some of these factors are not included in current GIB risk prediction models. such as anemia, co-administration of gemfibrozil, co-administration of verapamil or diltiazem, INR, heart failure, myocardial infarction, etc. Conclusions: The study found that anemia, co-administration of gemfibrozil, co-administration of verapamil or diltiazem, INR, heart failure, myocardial infarction et al. were associated with anticoagulation-related GIB, and these factors were not in the existing prediction models. This study informs risk prediction for anticoagulant-associated GIB, it also informs guidelines for GIB prevention and future research.

수량화 II 류에 의한 임도절토사면의 붕괴요인 평가 (The Evaluation of Failure Factors on Cutting Slopes of Forest Road by Quantification Theory(II))

  • 차두송;지병윤
    • Journal of Forest and Environmental Science
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    • 제18권1호
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    • pp.7-14
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    • 2001
  • 본 연구는 집중호우로 인하여 절토사면의 붕괴가 발생한 임도를 대상으로 수량화이론(II)을 이용하여 붕괴요인을 평가하였다. 그 결과는 다음과 같다. 임도 절토사면의 붕괴발생에 미치는 요인의 영향은 절토사면길이, 겉보기 토질, 사면방위, 절토사변경사, 산지경사 등 5개 요인이 가장 크게 나타났다. 특히, 절토사면길이는 8m 이상, 겉보기 토질은 토사, 사면방위는 북사면, 절토사변경사는 $60^{\circ}$이상, 산지경사는 $35{\sim}40^{\circ}$ 사이에서 사면붕괴에 기여도가 가장 크게 나타났다.

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Energy-based design base shear for RC frames considering global failure mechanism and reduced hysteretic behavior

  • Merter, Onur;Ucar, Taner
    • Structural Engineering and Mechanics
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    • 제63권1호
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    • pp.23-35
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    • 2017
  • A nonlinear static procedure considering work-energy principle and global failure mechanism to estimate base shears of reinforced concrete (RC) frame-type structures is presented. The relative energy equation comprising of elastic vibrational energy, plastic strain energy and seismic input energy is obtained. The input energy is modified with a factor depending on damping ratio and ductility, and the energy that contributes to damage is obtained. The plastic energy is decreased with a factor to consider the reduced hysteretic behavior of RC members. Given the pre-selected failure mechanism, the modified energy balance equality is written using various approximations for modification factors of input energy and plastic energy in scientific literature. External work done by the design lateral forces distributed to story levels in accordance with Turkish Seismic Design Code is calculated considering the target plastic drift. Equating the plastic energy obtained from energy balance to external work done by the equivalent inertia forces considering, a total of 16 energy-based base shears for each frame are derived considering different combinations of modification factors. Ductility related parameters of modification factors are determined from pushover analysis. Relative input energy of multi degree of freedom (MDOF) system is approximated by using the modal-energy-decomposition approach. Energy-based design base shears are compared with those obtained from nonlinear time history (NLTH) analysis using recorded accelerograms. It is found that some of the energy-based base shears are in reasonable agreement with the mean base shear obtained from NLTH analysis.