• Title/Summary/Keyword: failure factors

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

  • Shin, Dong-Hoon;Cho, Seong-Eun;Lim, Eun-Sang;Park, Han-Gyu
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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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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The Factors for Service Recovery of Family Restaurant and Mobile Telecommunication Service (패밀리레스토랑과 이동통신서비스의 서비스회복 결정요인)

  • Oh, Se-Gu
    • Journal of Korean Society for Quality Management
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    • v.35 no.4
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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

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

  • Song Eun-Kyeung;Kim Cho-Ja;Yoo Il-Young;Kim Gi-Yon;Kim Ju-Hyeung;Ha Jong-Won
    • Journal of Korean Academy of Nursing
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    • v.36 no.5
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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.

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

  • Park, J.H.;Shin, Y.J.;Lee, S.C.;Lie, C.H.
    • Journal of Korean Institute of Industrial Engineers
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    • v.36 no.1
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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.

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

  • Kim, Chang Hee;Lee, Mi Hyang
    • Journal of Korean Academy of Nursing Administration
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    • v.22 no.5
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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.

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

  • Cha, Du-Song;Ji, Byoung-Yun
    • Journal of Forest and Environmental Science
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    • v.18 no.1
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    • pp.7-14
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    • 2001
  • On the basis of data obtained from forest road collapsed due to a heavy rainfall, this study carried out to evaluate the cutting slope failure factors of forest road by using Quantification theory(II). The results were summarized as follows. The factors on cutting slope failure was ranked in the order of cutting slope length, soil type, aspect, cutting slope gradients and slope gradients. And the slope failure was mainly occurred under such conditions as cutting slope length longer than 8m, soil type with soil, aspect of N, cutting slope gradients steeper than 600 and slope gradients greater than $35{\sim}40^{\circ}$.

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Comparison on the Failure Mechanism of Punching Shear in the Reinforced Concrete (철근 콘크리트의 뚫림전단 파괴메카니즘에 과한 비교)

  • 이주나;연규원;이호준;박찬수
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.04a
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    • pp.533-538
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    • 2000
  • In R.C. flat slab system, a brittle punching failure is a very fatal problem. But there is no generally well-defined answer to the problem and there are wide differences in current practical design codes. therefore, in this study, the factors affecting to punching failure mechanism have been studied to find out the punching shear behavior in R.C. flat slabs by comparing other investigations and practical design codes. Therefore, In this study, the factors affecting to punching failure mechanism have been studied to find out the punching shear behavior in R.C. flat slabs by comparing other investigations and practical design codes. The conclusions in this study are summarized as follows; 1) The factors affecting to punching shear are concrete strength ($f_\alpha$), ratio of column side length to slab depth (c/d), ratio of distance from column center to radial contraflexure (l/d), yield strength of steel ($f_y$), flexural reinforcement ratio ($\rho$) and size effects. 2) It is shown that th use of $\surd{f_{ck}}$in applying($f_\alpha$ to punching shear strength estimation may be more sensitive in high concrete strength. 3) The effects of l/d, ($f_y$, size are no clear in the punching failure mechanism, so in the future, it should be investigated with the effects of various composed load.

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

  • Gwon Cheol Sin;Lee Jae Ha
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2002.05a
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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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Outcome Analysis of Endotracheal Intubation for General Ward Patients with and without Predicted Difficulty (일반병동 입원환자의 어려운 기도 예측 여부에 따른 기관 내 삽관의 결과 분석)

  • An, Ji-Young;Choi, Hye Ran
    • Journal of Korean Critical Care Nursing
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    • v.7 no.2
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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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    • v.39 no.1
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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.