• 제목/요약/키워드: Case Study

검색결과 58,813건 처리시간 0.069초

철도시스템에 대한 RAM Case 적용에 관한 연구 (A Study on the application of RAM Case for Railway System)

  • 백영구;송기태;김민호;이기서;신건영;이덕규
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2007년도 추계학술대회 논문집
    • /
    • pp.683-688
    • /
    • 2007
  • The importance of reliability and safety, recently, shows a tendency to increases in railway system constructions and projects. At the point of view of safety, especially, the railway authority proposes an establishment of the safety case that is the documented demonstration that products comply with the specific safety requirements in railway industry. In case of reliability activities, there is no systematic documented demonstration in the railway industry. At this circumstance, this study presents the establishment of Reliability, Availability and Maintainability Case for railway system based on the MoD(Ministry of Defence) 00-42. This RAM Case will support that systems and products produced from suppliers or manufacturers meet the specific RAM requirements during the system life cycle(i.e, from design to operation & maintenance) through systematic process and evidences. Also, it is expected that railway system operations will be managed and supported from reliability activities in accordance with RAM Case.

  • PDF

철도시스템의 안전운영 검증을 위한 Safety Case 사례연구 (A Case Study on Safety Case for the Verification of Railway Safety)

  • 곽상록;김상암;왕종배;조연옥
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2005년도 추계학술대회 논문집
    • /
    • pp.618-622
    • /
    • 2005
  • Railway safety case is an important measure for demonstrates operating company's capability, commitment and competence in accordance with Railway Regulation 2000 in UK. Safety case describes the scope of operation, definition and boundary of activity, risk analysis, system safety activity, annul safety plan. Relationships between' these components and company's policy, organization, human resource, control measure, investment plan are also included. A case study for Network Rail (infrastructure manager)'s safety case is described in this paper for the construction of safety rule and safety planning.

  • PDF

EVA(Ethylene Vinyl Acetate) 수지가 태양전지의 장기적인 수명에 미치는 영향에 관한 실험적 연구 (Experimental study on the effects of EVA(Ethylene Vinyl Acetate) for solar cell's long-term life)

  • 김선용
    • 대한안전경영과학회지
    • /
    • 제17권4호
    • /
    • pp.397-401
    • /
    • 2015
  • In this study, analysed the characteristics of power drop and surface damage in solar cell through high temperature and humidity test in the 3 case of EVA(ethylene vinyl acetate) and 2 case ribbon thickness. The solar cells were tested during the 500hr in $85^{\circ}C$ temperature and 85% relative humidity conditions, that excerpted standard of PV Module(KS C IEC-61215). Through the EL(Electroluminescence) shots, specimen's surface have partialy damaged. Before and after high humidity and high temperature test, ribbon thickness $200{\mu}m$ EVA1 case power drop rate was 8.463%, EVA2 case was 6.667%, EVA3 case was 6.373%. In the ribbon thickness $250{\mu}m$ EVA1 case power drop rate was 6.521%, EVA2 case was 8.517%, EVA3 case was 6.019%. EVA3 case was the lowest power and FF(fill factor) drop rate at the 2 case of ribbon thickness, because EVA3 is laerger than EVA1 and EVA2 in thickness, elongation and tensile strength.

미국 일리노이주 옥수수 재배 농경지 내 암거배수 시설 설계에 따른 배수량 및 질산성질소 배출 평가 (Assessment of Drainage Discharge and Nitrate-Nitrogen Loads According to Subsurface Drainage Design in Corn Cultivated Agricultural Land in Illinois, USA)

  • 황순호;정한석;바타라이 라빈
    • 한국농공학회논문집
    • /
    • 제66권3호
    • /
    • pp.15-23
    • /
    • 2024
  • Subsurface drainage improves crop productivity in poorly drained soils but may also substantially contribute impairment of surface water quality due to excess leaching losses of nutrients like Nitrate-Nitrogen (NO3-N). This research presents preliminary findings from a 3-years tile depth and spacing study in Illinois state that includes three drain spacings implemented in 2 plots. We found that the plot with the narrower subsurface drainage (Case 1) exported more drainage water compared to the plot with the narrower subsurface drainage system (Case 2). The total drainage water from Case 1 plot showed 57% more compared to Case 2 plot. Whereas we observed that the plot with narrower drain spacing (Case 1) exported only 9% more NO3-N leaching losses compared to the wider plot (Case 2). The average corn yield was observed higher in plot Case 1 compared to Case 2. Especially, we observed about 7% higher corn yield in plot Case 1 compared to Case 2 plot in the relatively dried year (2022). The preliminary findings for this study suggest that subsurface drainage systems can be optimized to reduce nutrient losses while improving the crop productivity.

골유착성 임플랜트 보철치료시 자연지대치와의 연결형태에 관한 유한요소적 응력분석 연구 (A STUDY ON THE CONNECTION MODALITY BETWEEN IMPLANT AND TOOTH IN OSSEOINTEGRATED PROSTHETIC TREATMENT USING FINITE ELEMENT ANALYSIS)

  • 김용호;김영수
    • 대한치과보철학회지
    • /
    • 제29권3호
    • /
    • pp.1-32
    • /
    • 1991
  • Tho osseointegrated dental prosthetic treatment has develped for the edentulous patient with severely resorbed alveolar ridge, and has given us a successful clinical results to date. Nowadays the partially edentulism is included among the indications of the osseointegrated prosthetic treatment. The purpose of this study was to analyze the stress distribution at supporting bone according to the types of connection modality between implant and tooth in the superstructure. Two dimensional finite element stress analysis was applied for this study. FEM models were created using software Super SAP for MBM 16bit personal computer. Three modalities of connection were modeled and analyzed under load condition. The results were as follws: 1. The stress develped at tooth and implant in the cancellous bone was lower in the case of rigid connection than in the case of norigid connection, but higher between the two implants in the case of rigid connection than in the case of nonrigid connection. 2. The stress developed at the cortical bone and at the supporting bone interface was lower in the case of rigid connection than in the case of nonrigid connection 3. The stress developed at the supporting tissue interface of the implant nearby the tooth, was lower in the case of rigid connection than in the case of nonrigid connection. 4. The stress developed at the supporting tissue interface of posteriormost implant, was same between the cases of rigid and nonrigid connection. 5. The stress distribution related to the freestanding case was generally similar to the stress distribution pattern of nonrigid connection case. 6. The magnitude of applied load which produces deformation within elastic limit, had influence on the absolute value of stress, but had no influence on the pattern of stress distribution of the same case.

  • PDF

가족사례관리사업 운영 현황 및 효율성 제고 방안에 관한 연구 : 서울지역 건강가정·다문화가족지원센터를 중심으로 (A study of current management status and ways to improve the efficiency of Family-centered case management services: Focused on the Healthy family support centers and Multi-cultural family support centers in Seoul)

  • 박정윤;박연숙;전미경
    • 가족자원경영과 정책
    • /
    • 제23권1호
    • /
    • pp.35-60
    • /
    • 2019
  • The main purpose of this study are to investigate the current situation of family-centered case management practices by case managers working in the healthy family support centers and multi-cultural family support centers, in order to propose a practical direction for improving the efficiency of family-centered case management services. Research participants included 24 case manager working in the healthy family support centers and multi-cultural family support centers in Seoul, who have performed case management services for families for one to 7 years. The Date was collected through focus group interview(FGI) and demographic characteristics research. The results of this study are as follows: first, in the area of cognition about family-centered case management conceptualization, confused and ambiguous. Seconds, in the area of practicing as a case manager, there were limitations and biases in community resources contact and multiple intervention and limited sharing information between organizations. Third, family-centered case manager's have periodically been requested to provide diverse training and education for performance of challenging case managers roles. The Standardized manual and burnout precautions should also be prepared.

지역사회 차원에서 본 이주노동자와의 통합에 관한 사례 연구 - 경기도 A읍 사례를 중심으로 - (A Case Study on Integration with Immigrant Workers in Local Community - Centered Kyung Ki Do. A Town Case -)

  • 김서영
    • 한국사회복지학
    • /
    • 제69권3호
    • /
    • pp.267-287
    • /
    • 2017
  • 본 연구는 지역사회 차원에서의 이주노동자와의 통합단계와 구체적 내용을 밝히고자 하는 목적을 지니고 있다. 연구자는 사례연구로 접근했다. 25명을 대상으로 심층면담을 수행하여 자료를 분석했다. 연구결과에 의하면 이주민들과의 통합은 상호 타자화 단계, 도구적 차원의 허용 단계, 저항과 상호 긴장 단계, 타협 단계, 상호 공존의 단계로 나타났다. 연구결과에 근거하여 사회통합 방안으로 이주민의 임파워먼트, 외국인 혐오와 인종주의 철폐를 제안했다.

  • PDF

사례기반학습이 간호대학생의 문제해결능력, 자기주도학습능력과 학업적자기효능감에 미치는 효과 (The Effects of Case-Based Learning on Problem-Solving Ability, Self-Directed Learning Ability, and Academic Self-Efficacy)

  • 김지숙;최희정
    • 대한통합의학회지
    • /
    • 제9권1호
    • /
    • pp.141-150
    • /
    • 2021
  • Purpose : The purpose of this study was to investigate the effect of case-based learning application in human growth development classes on nursing students' problem-solving ability, self-directed learning ability, and academic self-efficacy. Methods : The research method was a self-report questionnaire before and after case-based learning for second-year nursing students who took the human growth development course at U University in K city. The collected data were statistically processed using SPSS WIN 21.0. Results : The results of the study showed that after case-based learning, problem-solving ability, self-directed learning ability, and academic self-efficacy were all significantly improved. In addition, as a result of examining the correlation between each variable after case-based learning, problem solving ability score and self-directed learning ability score (r=.54, p<.01), and problem solving ability scores and academic self-efficacy scores (r=.44, p<.01), were significantly correlated with self-directed learning ability scores and the academic self-efficacy reduction scores (r=.76, p<.01). Conclusion : The results of this study suggested the need for various learning programs such as case-based learning to improve nursing students' problem-solving abilities and self-directed learning abilities and their application. In addition, to improve the learning self-efficacy of nursing students, a continuous and systematic study is suggested to develop and apply customized educational programs according to the learners' preferences. Since the sample group in this study was limited to one university, there were few cases and no control group, so there are limitations in generalizing the test effect, However, significant differences a were verified in the case-based learning pre-tests and post-tests.

X선진단(X線診斷) 부문(部門)에 있어서 업무량(業務量)에 관(關)한 조사연구(調査硏究)(II) (A Study on Activities of Diagnostic X-ray Examination(II))

  • 경광현;허준
    • 대한방사선기술학회지:방사선기술과학
    • /
    • 제1권1호
    • /
    • pp.44-54
    • /
    • 1978
  • This study was carried out with statistical materials during the last two years of period from Jan. 1975 to Dec. 1976 which presented at radiologic department of 5 hospitals in Seoul City. The primary purpose of this study was to obtained more detailed informations related to the activities of radiologic technologists in diagnostic X-Ray examinations part and to provide some basic materials for managements in activities of then and manpower managements of their organization and practice. From the results of this study, the following conclusions were obtained [1] During two year from the January of 1975 to the December of 1976, total number of case in X-ray examinations were 464,830 case and 22,029 case in 1975 and 24,461 in 1976. And ratio of icreased in X-Ray examinations by year was 11.09 per cent. [2] Regarding the examined portion of X-Ray examination, a great propotion was chest examination as 56.88 per cent. [3] An average, the required time per case in X-Ray exam. was 9.28 minutes and make used of 1.94 sheets of X-Ray film per case in radiography. [4] An average, ratio of increased in X-Ray film by year was 12.71 per cent and ratio of failed film in it was 2.23 per cent. [5] The frequency rate of film size showed the highest distribution of $8"{\times}10"$(28.17%) and the highest distribution of X-Ray film by month was July(8.93%). [6] An average, the amount of activities per a diagnostic X-Ray equipment was 34.92 case and make used of 67.81 sheets of X-Ray film in a day. [7] The mean number of case in X-Ray examinations by radiologic technologists was 29.29 cases and make used of 56.87 sheets of X-Ray film in a day. Also, the average number of case was reading by radiologists was 32.42 case and 62.97 sheets of X-Ray film in a day.

  • PDF

클램프에서 예하중의 영향에 관한 연구 (A Study on the Effect of Preloading in Clamp)

  • Han, D.M.;Lee, S.S.;Lee, D.R.
    • 한국정밀공학회지
    • /
    • 제14권8호
    • /
    • pp.29-39
    • /
    • 1997
  • The clamp, as the structure which is used for supporting the pipe in the atomic power plant, is produced with a certain degree of anticlastic curvature in the current manufacturing process. In this study, the structural analysis of the clamp and the pipe was performed using ABAQUS. And the finite element modelling for the analysis was made by an HyperMesh. The contact forces which are transferred between the clamp and the pipe for the external force are changed according to the binding force of bolts and keeps the clamp tightly and protects the slipping between the clamp and the pipe. The clamps with the anticlastic curvature and with the flat curvature are considered in order to invest the anticlastic effect. In this study, another case is suggested. The present case does not have the stiffness ring on the end of the clamp but the suggested case has the ring. For the present case, the results showed that the equivalent stress is higher in the anticlastic curvature case than in the flat curvature case and the equivalent stresses on the pipe are almost the same as the binding force increses. For the suggested case, the result showed that the equivalent stress in the anticlastic curvature case decreases until some binding force and increases as the binding forces increase and is lower in some range than in the flat curvature case. From this study, the clamp with the anticlastic curvature in the suggested method is better than the clamp with the flat curvature and the optimal binding force are given.

  • PDF