• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 1997년도 추계학술발표회논문집(1)
• /
• pp.695-700
• /
• 1997

To enhance the safety of nuclear power plants, implementation of accident management has been suggested as one of most important programs. Specially, accident management strategies are suggested as one of key elements considered in development of the accident management program. In this study, generally applicable accident management strategies to domestic nuclear power plants are identified through reviewing several accident management programs for the other countries and considering domestic conditions. Identified strategies are as follows; 1) Injection into the Reactor Coolant System, 2) Depressurize the Reactor Coolant System, 3) Depressurize the Steam Generator, 4) Injection into the Steam Generator, 5) Injection into the Containment, 6) Spray into the Containment, 7) Control Hydrogen in the Containment. In addition, the systems and instrumentation necessary for the implementation of .each strategy are also investigated.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2006년도 추계학술대회 논문집
• /
• pp.1126-1131
• /
• 2006

Risk assessment of a railway system should be periodically conducted managing a large amount of accumulating accident/incident data and scenarios, which generally requires enormous time and efforts. Therefore, special information management system is essential for railway risk assessment, where data needed for decisions on managing the railway safety could be promptly supported. The objective of this study is to develop a railway accident analysis program for risk assessment. The program is application running on the web which links railway accident analysts throughout the railway industry to a central database. Data entered, together with associated code tables. is stored on MS-SQL database. The program uses the concepts of accident, safety events, causes, related factors(vehicle, person, infrastructure, tool/equipment), recommendations to bring together the various elements of railway accidents. The program will be useful in finding hazard conditions, accident scenarios, quantitatively assessing the risk, and providing pertinent risk measures, eventually serving to prevent railway accidents and reduce severities of railway accidents.

• 자동차안전학회지
• /
• 제10권1호
• /
• pp.27-31
• /
• 2018

This paper reports an analysis of cyclist accident cases with respect to passenger vehicles on Korean roads. A typology based on Initiative for the Global Harmonization of Accident Data (iGLAD) code book is applied to a traffic accident analysis system(TAAS), which has the real-world crash data on Korea roads, to understand the accident scenarios in more detail and efficiently. Similarly this typology has been used for Germany In-Depth Accidents Study (GIDAS) as well. The accident data analysis with consideration of the typology of Korean road conditions may prioritize traffic safety issues regarding cyclists and is aimed to develop an Automatic Emergency Braking (AEB) system for cyclist. In summary, this paper characterizes and analyzes the scenarios of cyclist crashes with passenger car. The most common accident scenarios on Korean roads are Car-to-Bicyclist Nearside Adult (CBNA) and Car-to-Bicyclist Longitudinal Adult (CBLA), which are more than 86% of total accidents cases. Therefore, it is inferred that AEB cyclist system should include these accident types in the operational design domain to reduce more fatality in Korea.

• Nuclear Engineering and Technology
• /
• 제44권4호
• /
• pp.393-404
• /
• 2012

After the Fukushima nuclear accident in 2011, there has been increasing concern regarding severe accidents in nuclear facilities. Severe accident scenarios are difficult for operators to monitor and identify. Therefore, accurate prediction of a severe accident is important in order to manage it appropriately in the unfavorable conditions. In this study, artificial intelligence (AI) techniques, such as support vector classification (SVC), probabilistic neural network (PNN), group method of data handling (GMDH), and fuzzy neural network (FNN), were used to monitor the major transient scenarios of a severe accident caused by three different initiating events, the hot-leg loss of coolant accident (LOCA), the cold-leg LOCA, and the steam generator tube rupture in pressurized water reactors (PWRs). The SVC and PNN models were used for the event classification. The GMDH and FNN models were employed to accurately predict the important timing representing severe accident scenarios. In addition, in order to verify the proposed algorithm, data from a number of numerical simulations were required in order to train the AI techniques due to the shortage of real LOCA data. The data was acquired by performing simulations using the MAAP4 code. The prediction accuracy of the three types of initiating events was sufficiently high to predict severe accident scenarios. Therefore, the AI techniques can be applied successfully in the identification and monitoring of severe accident scenarios in real PWRs.

• Nuclear Engineering and Technology
• /
• 제54권7호
• /
• pp.2475-2490
• /
• 2022

The Accident Tolerant Fuel (ATF) is a new concept of fuel, which can not only withstand the consequences of the accident for a longer time, but also maintain or improve the performance under operating conditions. ISAA is a self-developed severe accident analysis code, which uses modular structures to simulate the development processes of severe accidents in nuclear plants. The basic version of ISAA is developed based on UO₂-Zr fuel. To study the potential safety gain of ATF cladding, an improved version of ISAA, referred to as ISAA-ATF, is introduced to analyze the station blackout accident of PWR using ATF cladding. The results show that ATF cladding enable the core to maintain a longer time compared to zirconium alloy cladding, thereby enhancing the accident mitigation capability. Meanwhile, the generation of hydrogen is significantly reduced and delayed, which proves that ATF can improve the safety characteristics of the nuclear reactor.

• 대한교통학회지
• /
• 제23권2호
• /
• pp.95-106
• /
• 2005

교통사고는 도로기하구조, 교통특성, 운전자 특성, 주변환경 등이 복합적인 상호작용을 통하여 발생하게 된다. 고속도로는 양호한 도로기하구조 조건을 가지고 있으나 고속주행 특성으로 인해 사고원인 중 부주의, 졸음, 과속 등 운전자의 인적요인(Human Factor)에 의한 사고비율이 매우 높다고 보고되고 있다. 그러나 고속도로 교통사고 추정에 대한 기존연구들은 주로 특정지점에서의 도로기하구조조건, 교통 및 환경조건들과 교통사고와의 관계를 설명하기 위한 모형의 개발에 초점을 두어왔으며, 운전자 조건을 고려한 교통사고 추정에 대한 연구는 지금까지 거의 수행되지 않았다. 따라서 기존 연구들은 도로와 교통조건이 양호한 구간에서의 높은 교통사고율을 설명하기 어렵다는 한계를 가지고 있다. 본 연구의 목적은 개별 기 ${\cdot}$ 종점 쌍간의 통행길이분포(Trip Length Frequency Distributions)를 이용하여 공간적 시간적으로 변화하는 운전자의 심리적 ${\cdot}$ 생리적 인적요인을 고려하여 보다 현실적으로 교통사고발생율을 예측하는데 있다. 이를 위해 사고분석변수로 구간교통량에 대한 사고위험교통량의 비율인 잠재사고비율(PAR:Potential Accident Ratio)이라는 새로운 개념을 제시하였으며, 서해안 고속도로에 대한 사례분석결과 PAR, 교통량과 교통사고는 서로 밀접한 관계를 갖는 것으로 분석되었다.

• 대한안전경영과학회지
• /
• 제22권1호
• /
• pp.45-50
• /
• 2020

The number of elevators in Korea has surpassed 700,000 units in 2019, which is the 8th in the world by number of installed units and 3rd in the world by new units. The word 'lift' is a representative word, and the category includes elevators, escalators, dumb waiters, and moving walks. Those who live in the city will experience using elevators once or twice a day, and these elevators are becoming an indispensable means of transportation when using high-rise apartments or subways. However, such a convenient elevator also has a lot of risks that threaten the safety of the user and actually cause many accidents every year. In particular, escalators (including moving walks), which account for as little as 5% of all elevators, account for 70% of all elevator accidents. According to Heinrich's chain of thought theory, accidents are caused by a combination of factors, which are divided into five stages: Stage 1: Genetic Factors and Social Environment, Stage 2: Individual Defects, Stage 3: Unsafe behavior and Unsafe conditions, Stage 4: Accident, Stage 5: Injury. Heinrich said that three of these five phases, unsafe behavior and unsafe conditions, require safety management and efforts to prevent accidents. In escalator accidents, the analysis of accident cases that have occurred so far will be related to unsafe behaviors and unsafe conditions, and the effective management of these causes of accidents will enable safer and more convenient use of escalators. This study analyzed accident cases of elevator users, focusing on escalator accidents over the last 10 years (2010 ~ 2019), and safety management to prevent safety accidents of elevator users by analyzing the behavior of actual users and questionnaires of experts in related fields. The method was studied.

• Journal of Radiation Protection and Research
• /
• 제6권1호
• /
• pp.45-52
• /
• 1981

The March 1979 accident at Three Mile Island provided physicians specializing in radiation medicine an opportunity to observe the field under conditions never seen before. Since no, injuries occurred at the site or within the community, medical personnel were immediately involved in efforts to allay fear, provide accurate information, and replace labortory resources rendered ineffective by the release in the reactor building. Valuable insights concerning medical emergency planning are derived from the accident; suggestions are made for handling any future mishaps.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
• /
• pp.39-40
• /
• 2017

High temperatures and humidity in summer strongly affect conditions of construction workers. These could lead to safety accidents and results in fatal accidents. This study, based on 3 years of weather and fatal accident data, explains the association between fatal accidents in summer and discomfort index and proposes management directions.

• 한국공간구조학회:학술대회논문집
• /
• 한국공간구조학회 2005년도 춘계학술발표회 및 정기총회 2권1호(통권2호)
• /
• pp.161-166
• /
• 2005

In spatial structures with large spaces, one important issue in structures with large spaces is how to carry the weight of the roof. A tensegrity cable dome structure is a kind of soft structural system using the tension cable and compression column as a main element. The tensegrity cable dome is built into a variety of shape around the world but then a collapse accident is increasing. Owing to a collapse accident we must grip of the collapse mechanism to prevent an accident and construct the structure with safety and economy. In this study, I investigated the unstable characteristics of the Geiger-type and Flower-type tcnsegrity cable dome structures, which is the lightweight hybrid structures using compression and tension elements continuously, according to the difference of loading conditions.