• 제목/요약/키워드: Safety case

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Improvement in the DNBR Modeling of RETRAN for Safety Analyses of Westinghouse Nuclear Power Plants

  • Cheong, Ae-Ju;Kim, Yo-Han
    • Nuclear Engineering and Technology
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    • 제34권6호
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    • pp.596-609
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    • 2002
  • Korea Electric Power Research Institute has developed the in-house safety analysis methodologies for non-LOCA(Loss Of Coolant Accident) events based on codes and methodologies of vendors and Electric Power Research Institute . According to the new methodologies, analyses of system responses and calculation of DNBR(Departure from Nucleate Boiling Ratio) during the transient have been carried out with RETRAN code and a sub-channel analysis code, respectively. However, it takes too much time to calculate DNBR for each case using the two codes to search for the limiting case from sensitivity study. To simplify the search for the limiting case, accordingly, RETRAN code has been modified to roughly calculate DNBR using hot channel modeling. The W-3 correlation is already included in RETRAN as one of the auxiliary DNBR models. However, WRB-1 and WRB-2 correlations required to analyze some Westinghouse type fuels are not considered in RETRAN DNBR models. In this paper, the RETRAN DNBR models using the correlations have been developed and the partial and complete loss of forced reactor coolant flow events have been analyzed for Yonggwang units 1 and 2 with the new methodologies to validate the models. The results of the analyses have been compared with those mentioned in the chapter 15 of the Final Safety Analysis Report.

틸팅차량의 곡선부 틸팅동작 시 윤중감소율 병화에 대한 고찰 (The study of wheel unloading change in case of tilting actuation)

  • 김남포;김정석;오일근
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.435-442
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    • 2004
  • Tilting train allow the train to pass curve at higher speed without affecting passenger comfort. As the tilting trains run curve track about 30$\%$ higher than non-tilting trains, the centrifugal force and dynamic force will be higher. Therefore it is very important for tilting train to ensure safety against derailment, and to reduce the lateral track forces by applying light-weight design, optimized suspension design and steering mechanism. The 180 km/h Korean Tilting Train(TTX) which is now developing as a part of the Korean National R & D project, was designed and analytically verified to meet these special requirements. This paper describes the analytic study to verify the safety against derailment, especially on the wheel unloading in case of tilting actuation. The severest curve geometry and curving speed was assumed, the tilting control pattern was also assumed as trapezoidal force function applied to tilting bolster and bogie frame. For the comparison, the operation with the speed of tilting train without tilting actuation was numerically simulated and the operation with the balanced speed without tilting actuation was also numerically simulated. Through the numerical simulation of various operating case, we found that derailment quotients, wheel unloading and Q/P was not affected by tilting actuation and that the bogie of TTX was nicely designed to satisfy the safety against the derailment.

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태양광 발전설비의 침수 시 설비영향 및 전기적 안전성 평가 (An Assessment on Effect of Facility and Electrical Safety During the Flooding of the Photovoltaic Power System)

  • 박찬엄;정진수;한운기;임현성;송영상
    • 조명전기설비학회논문지
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    • 제28권12호
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    • pp.38-44
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    • 2014
  • The photovoltaic power system is performing power generation by being installed in outdoors. Therefore it has the characteristics affected by environmental factors. In particular, if the solar power generation facility connected to the grid, the power can be generated continuously in a state of being secured operating voltage of the inverter and solar irradiation. In that case, if an abnormal situation such as flooding or heavy rains has occur, the possibility of electric shock or damage of facilities due to current leakage or a floating matters is present. In this paper, we performed electrical safety assessment about the connection part, junction box and cable of the solar module when the solar power system was flooded. we also assessed whether or not the leakage current is occurred in case of the cable was damaged. As a result, in case of the leakage current is large, we can be known that it is the risk of electric shock as well as cause of inverter damage.

Radiofrequency in arthroscopic shoulder surgery: a systematic review

  • Neeraj Vij;Joseph N. Liu;Nirav Amin
    • Clinics in Shoulder and Elbow
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    • 제26권4호
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    • pp.423-437
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    • 2023
  • Background: Radiofrequency has seen an increase in use in orthopedics including cartilage lesion debridement in the hip and knee as well as many applications in arthroscopic shoulder surgery. The purpose of this systematic review is to evaluate the safety and usage of radiofrequency in the shoulder. Methods: This systematic review was registered with PROSPERO (international registry) and followed the preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) guidelines. Embase and PubMed were searched using: "shoulder," "rotator cuff," "biceps," "acromion" AND "monopolar," "bipolar," "ablation," "coblation," and "radiofrequency ablation." The title and abstract review were performed independently. Any discrepancies were addressed through open discussion. Results: A total of 63 studies were included. Radiofrequency is currently utilized in impingement syndrome, fracture fixation, instability, nerve injury, adhesive capsulitis, postoperative stiffness, and rotator cuff disease. Adverse events, namely superficial burns, are limited to case reports and case series, with higher-level evidence demonstrating safe use when used below the temperature threshold. Bipolar radiofrequency may decrease operative time and decrease the cost per case. Conclusions: Shoulder radiofrequency has a wide scope of application in various shoulder pathologies. Shoulder radiofrequency is safe; however, requires practitioners to be cognizant of the potential for thermal burn injuries. Bipolar radiofrequency may represent a more efficacious and economic treatment modality. Safety precautions have been executed by institutions to cut down patient complications from shoulder radiofrequency. Future research is required to determine what measures can be taken to further minimize the risk of thermal burns.

설문조사에 의한 근로자 중심의 안전분임토의를 통한 건설업 위험성 평가 개선방안 사례연구 (A Case Study on the Improvement of Risk Assessment by Worker-Oriented Safety Circle Discussion in Construction Industry by the Survey)

  • 김정훈;오태근
    • 한국안전학회지
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    • 제31권5호
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    • pp.82-88
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    • 2016
  • The current risk assessment system do not reflect workers' various opinion. However, the worker actually are in the center of work field and are exposed to accidents. In this regard, this study suggests enhanced risk assessment by 'safety circle discussion' on workers' hand. The self-administered surveys on supervisors and workers were done for the effect analysis of the safety circle discussion. According to the question investigation, even though the current risk assessment causes difficulties in preventing accidents by unsafe behaviors, the worker-oriented safety circle discussion establishing measures for risk factors of each work type will be able to prevent accidents more effectively. Also, it can positively contribute to safety health awareness, industrial accident prevention, accurate recognition on risk factors, improving safety facilities/work conditions, workers' compliance to safety health rules. Lastly, most respondents agreed that it is necessary to form organic relationship through circle discussion and deriving safety inspections that workers participate.

필수성능 분석을 통한 효율적인 의료기기 기능안전 접근 방안 (Efficient Approaches of Functional Safety for Medical Equipment using Essential Performance Analysis)

  • 김기영;유기훈;박호준;장중순
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제15권1호
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    • pp.27-32
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    • 2015
  • Functional safety is part of the overall safety relating to the equipment under control (EUC) and the EUC control system that depends on the correct functioning of the electrical/electronic/programmable electronic (E/E/PE) safety-related systems. Since the complexity of the medical equipment is increased, manufactures have to obtain functional safety as well as basic safety. This study proposes a perspective for applying functional safety to medical equipment. The research is carried out with respect to overall safety life-cycle of functional safety and essential performance of the medical equipment. The relationship between functional safety and essential performance is identified centered on the safety function. The essential performance using E/E/PE systems is defined as a safety function of functional safety. This approach is applied to a ultrasound imaging system as a case study.

영국 철도 민영화에 있어 철도안전의 성과와 과제 (The Outcomes and Tasks of UK Rail Privatization in case of Safety)

  • 이용상
    • 한국철도학회논문집
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    • 제9권2호
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    • pp.212-221
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    • 2006
  • This paper examines the outcomes and tasks of U rail privatization especially focusing on the rail safety. Earlier research which focused on the rail safety had little knowledge of the explanations for recent changes of safety scheme. Moreover, they had difficulty making a direct comparison of safety between national rail and the privatized rail. Therefore we are left without a good explanation which has a comprehensive perspective. I attempt to show the outcomes of safety in the rail privatization process and its tasks focusing on the recent fatal accident. This paper argues that the UK's rail safety has a framework which is too complicated with overlapping responsibilities that brought about inefficiency, increasing costs. Especially infrastructure enterprise did not come to play an appropriate role. However, after 2000, the government took charge of setting the strategy for railway safety, and the Office of Rail Regulation covered safety, performance and cost. I explain that these changes present a good opportunity to solve the problem of passing the buck for rail accident. Through the analysis, I find that outcomes of rail privatization in safety are improved comparing the national rail. However, safety performance, for example the collision of structures of cars and looseness of rail should be improved. In future, the problems of fatal accident and a bit of duplicate safe system should be addressed.

LED가 적용된 안전조끼의 프로토타입 개발에 관한 연구 (A Study for Developing the Prototype of LED-Safety Vest)

  • 김미현
    • 복식문화연구
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    • 제18권3호
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    • pp.488-498
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    • 2010
  • This study was intended to develop a multi-purpose, multi-functional design for safety vest to enhance the safety and user's availability. With a limited scope to LED-applied safety vest, this study contemplates on the problems of safety vest on the market and directions for design development with a view to develop its prototype. This is a significant study because it has been conducted concerning a prototype, a cut above the study method of constructing a basic theory. For study method, theoretic considerations on LED and safety vest are followed by case study for LED-applied safety vest currently on the market to draw out problems. Then, solutions for problems with LED safety vest will be found, while planning for a design direction in consideration of safety, functionality and beauty. Scope of study was limited to cases of LED safety vests currently on sale online and offline, excluding cases of common-form luminosity such as HB luminous vest without LED. Accordingly, results of study will help develop the prototype for LED safety vest with an increase of the wearer's safety, and be used as a basic data for developing high-value-added fashion prodcts to meet his aesthetic sense and functionality. This study has limitations. Restricted scope for LED-applied safety vest should be extended to an outdoor wear in follow-up research for the foundation of higher value added.

환자안전 관련 법의 구조와 현황 (A Legal Framework for Improving Patient Safety in Korea)

  • 옥민수;김장한;이상일
    • 보건행정학회지
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    • 제25권3호
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    • pp.174-184
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    • 2015
  • This paper reviewed structure and current status of laws related to patient safety using patient safety law matrix to promote systematic approach in legal system of patient safety. Laws related to patient safety can be divided into three areas: laws for preventing; laws for knowing about; and laws for responding. In the case of Korea, gaps are especially prominent in the areas of laws for knowing about and responding. Patient safety law which will be enacted in July 2016 will fill the gap in the area of laws for knowing about. This law will be comprehensive law, covering the full spectrum of laws related to patient safety. However, after reviewing current patient safety law in Korea, the following drawbacks were identified: absence of code for grasping the current patient safety level; absence of code for mandatory reporting in patient safety reporting system; and absence of code for privilege about patient safety work product. Furthermore we need wider discussions about covering issues of open disclosure, apology law, coroners system, and complaint management system in patient safety law.

Ensuring Patient Safety in Pediatric Dental Care

  • Daewoo Lee
    • 대한소아치과학회지
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    • 제51권2호
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    • pp.109-131
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    • 2024
  • This review aims to examine safety concerns in pediatric dental care and underscore the need for comprehensive patient safety initiatives within the Korean Academy of Pediatric Dentistry. Drawing insights from the prevailing patient safety policies of the American Academy of Pediatric Dentistry, case reports, and systematic reviews, this review elucidates issues such as dental fires during sedation, ocular complications from local anesthesia, and surgical emphysema. This review highlights the significance of safety toolkits encompassing infection control, medical error reduction, dental unit waterline infection, and nitrous oxide safety in pediatric dental settings, underscoring the need to foster a safety culture. Furthermore, this study explores the curriculum for pediatric dentistry residency programs, emphasizing concepts such as high-reliability organizations and mortality and morbidity conferences. The study suggests the need for initiatives to enhance patient safety, including establishing safety committees, expanding reporting systems, policy development, and supporting research related to patient safety. In conclusion, this study underlines key messages, emphasizing the utmost priority of patient safety, acknowledging the inevitability of human error, promoting effective communication, and cultivating a patient safety culture. These principles are vital for advancing patient safety in pediatric dental care and improving outcomes among pediatric patients.