• 한국가스학회지
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• 제15권1호
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• pp.46-53
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• 2011

최근에 정보기술 패러다임은 유비쿼터스 기술이 도입되면서 스마트 서비스 환경으로 변화하고 있다. 도로, 상하수도, 가스 등과 산업 시설물에 유비쿼터스 기술이 접목되어 비용 감소 및 사고 예방성 향상이 높아지면서 관련된 연구 및 기술이 가속화되고 있다. 그러나 현재까지 공통환경 IT기술 위주로 개발되어 산업 도메인 특성이 고려되지 않았기 때문에 유비쿼터스 기술이 생활환경 및 산업시설에 활발하게 도입되지 못하고 있다. 본 논문은 도시가스 주요시설에 유비쿼터스 기술을 도입하기 위하여 현장지향형 무선 데이터 전송 인프라를 구축하고 효율적인 서비스를 제공하는 무선기반 도시가스 안전관리 시스템을 목적으로 한다.

• Nuclear Engineering and Technology
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• 제46권6호
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• pp.817-824
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• 2014

To ensure the safety of research reactors, the water level must be maintained above the required height. When a pipe ruptures, the siphon phenomenon causes continuous loss of coolant until the hydraulic head is removed. To protect the reactor core from this kind of accident, a siphon breaker has been suggested as a passive safety device. This study mainly focused on two variables: the size of the pipe rupture and the timing of air entrainment. In this study, the size of the pipe rupture was increased to the guillotine break case. There was a region in which a larger pipe rupture did not need a larger siphon breaker, and the water flow rate was related to the size of the pipe rupture and affected the residual water quantity. The timing of air entrainment was predicted to influence residual water level. However, the residual water level was not affected by the timing of air entrainment. The experimental cases, which showed the characteristic of partical sweep-out mode in the separation of siphon breaking phenomenon [2], showed almost same trend of physical properties.

• Nuclear Engineering and Technology
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• 제42권4호
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• pp.394-413
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• 2010

The object of this paper is to identify the key elements that impact a radiation dose at EAB (Exclusion Area Boundary). This study is based on the AST (Alternative Source Terms) as defined in Regulatory Guide 1.183. The LOCA (Loss of Coolant Accident) and the LRA (Locked Rotor Accident) are selected as limiting cases. A sensitivity analysis of accidental behavior with respect to various parameters during LOCA and LRA at Kori Unit 1 is also undertaken for the following objectives: to determine the limiting parameters, to find the impact trend of the radiation dose, and to find the safety margin between AST and TID (Technical Information Document) methodologies. This work confirms that key parameters are particulate removal rate, decontamination factor, iodine chemical form, gap fraction, partitioning factor, and the impact of isotopes group. Comparing TID with AST, the radiation dose of TID is about 80% greater than that of AST under a LOCA, and about 60% greater than that of AST for the case of a LRA; thus the safety margin is remarkably increased when the AST is used. In this work, the sensitivity analysis results are presented in terms of a sensitivity index called the "NDD (Normalized Dose Difference)", which compares the impact of parameters with that of a reference case. These values are derived by using a combination of the leak rate (primary to secondary), iodine chemical form, gap fraction, partitioning factor, spray removal rate, source term, and other variables.

• Nuclear Engineering and Technology
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• 제56권1호
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• pp.19-33
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• 2024

In nuclear thermal-hydraulic system codes, most correlations used for vertical pipes, under downward two-phase flow, have been developed considering small pipes or pool systems. This suggests that there could be uncertainties in applying the correlations to accident scenarios involving large vertical pipes owing to the difference in the characteristics of two-phase flows, or flow conditions, between large and small pipes. In this study, we modified the Multi-dimensional Analysis of Reactor Safety KINS Standard (MARS-KS) code using correlations, such as the drift-flux model and two-phase multiplier, developed in a plant-scale air-inflow experiment conducted for a pipe of diameter 600 mm under downward two-phase flow. The results were then analyzed and compared with those based on previous correlations developed for small pipes and pool conditions. The modified code indicated a good estimation performance in two plant-scale experiments with large pipes. For the siphon-breaking experiment, the maximum errors in water flow for modified and original codes were 2.2% and 30.3%, respectively. For the air-inflow accident experiment, the original code could not predict the trend of frictional pressure gradient in two-phase flow as / increased, while the modified MARS-KS code showed a good estimation performance of the gradient with maximum error of 3.5%.

• 한국인터넷방송통신학회논문지
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• 제14권6호
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• pp.159-162
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• 2014

최근 추세를 중심으로 특허청 분석에 따르면 12~08년 최근 5년 사이 엘리베이터 안전관련 특허출원이 급증하는 것을 확인할 수 있었고, 이를 안전에 대한 관심이 높아지고 있는 것으로 예측했다. 이에 본 논문은 13~09년 사이 승강기 안전 관련 특허자료를 취합 및 분석 후 시대별로 공통적으로 중요시 되는 승강기 안전요인이 안전제어, 비상제동, 도어개폐장치라는 것을 확인하였다. 신뢰성 분석을 통해 승강기 안전에 있어서 가중치가 높은 항목을 이 세 가지로 정의하고, 특허가 많이 출원된 요인을 시대적 배경을 통해 알아보고, 5년간의 자료를 기반으로 승강기 안전에 대한 사고예방기술을 종합하여 키넥트 장착 스카다시스템 승강기를 향후 승강기 제작 방향으로 제시한다.

• 선박안전
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• 통권28호
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• pp.36-45
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• 2010

While the vessel become bigger and high speed, navigational passages become narrow due to an enlargement of all sorts of new ports, sea-crossing bridges and anchorages, leading to the high probability of marine accidents. Furthermore, a constant increase in the maritime transportation and the traffic volume on the sea led to a variety of sea traffic environments and it is a trend for the demand for the sea transportation environment to increase steadily. At this point of time, the Ministry of Land, Transport, and Maritime Affairs introduced the Korea Maritime Safety Laws evaluating the degree that The Safety Audit System for maritime transport, which evaluates the degree that all kinds of port facilities installed temporarily or installed into navigational passages, and the installations and repair constructions of S.O.C. facilities affect ships' traffic safety, was introduced through Korea Maritime Safety Laws and went into effect from November 28th, 2009. This study was performed to introduce an outline including the concept and purpose of the Maritime Safety Audit(MSA) system for maritime transport and the technological guidelines for scientific and standardized enforcement, thereby analyzing the system.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1584-1589
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• 2007

Plug-in type door is installed in recently designed tube. It is world wide trend to fulfill the customer's demand. But, plug-in door need widely gap between doorway and platform and it is raise an serious accident. Therefore, newly designed train must have safety device like a sliding step to prevent incident. This paper present about development process for sliding step. Trend of sliding step, development plan, course, technical description, and etc. will be included in this paper.

• 항공우주산업기술동향
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• 제8권2호
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• pp.105-112
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• 2010

항공기 사고가 발생하면 항공기 동체가 파손되어 물질 및 인명의 피해 규모가 매우 크다. 이러한 사고를 방지하기 위한 기술적인 접근 방법으로서 실시간 안전진단시스템이 전 세계적으로 개발되고 있으며, 우리나라에서도 국토해양부 사업의 일환으로 소형항공기용 실시간 안전진단시스템이 개발되고 있다. 본 논문에서는 항공기 사고의 예방을 위한 실시간 안전진단시스템의 국내외 기술개발 동향에 대하여 기술하고자 한다. 또한 국내에서 수행 중인 연구개발 과제에 대하여 살펴보고, 해당 시스템의 구성 및 기능과 예상 성과에 대하여 살펴본다.

• 대한인간공학회지
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• 제23권4호
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• pp.23-34
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• 2004

The importance of the industrial safety has been growing gradually as well as the prevention activities on industrial accidents. Industrial accident rates have been decreasing by the prevention activities. However, the fatal industrial accidents such as the death tend to increase and risk per accident has increased. The previous studies on the industrial accidents focus on the entire accidents. However, these studies are lacking for the fatal industrial accidents such as the death. The purpose of this paper is to analyze the characteristics and trend of death which occurred by industrial accident, based on the real data of deaths collected last 5 years from 1999 to 2003 in korea. This paper suggests a analysis method using MDS(MultiDimensional Scaling) that considers accidents variables and properties simultaneously. We evaluate MDPREF (Multidimensional Analysis of Preference Data), one of the MDS analysis, to know the relations between the type of industry and region as well as the type of industry and occupation. This paper finds the type of industry which has high possibilities of death by regional groups. In addition, we find the type of occupation which has high possibilities of death by the type of industry. These findings indicate that industrial classification should be differently controled according to type of occupation and region.

• 한국항공운항학회지
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• 제23권2호
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• pp.21-31
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• 2015

The world air transport industry has grown steadily with quantitative expansion. The volume of air transport in the world is skyrocketing with the open-sky trend. Air passengers from or to South Korea has shown 5% of annual growth for the last couple of decades which caused South Korea now ranking in 18th in the World for air transport market size. Quantitative expansion of Air transport affects in policy making of air transport operators, such as airports, airlines or authorities, directly and indirectly. Especially, Aviation Safety field should be supported by policy regime with the growth of air transport volume, assured resources for continuous monitoring is standing out as a vital factor. This study is to estimate social costs caused by aviation accidents and investment costs for aviation safety by airports, airlines and authorities as operators. Estimated investment costs for aviation safety verified by comparing and analysing them. Precedent studies were reviewed to refer research methodology to calculate aviation accident costs and safety costs of operators. Safety costs of operators was calculated with literature researches and interview surveys among professionals of each operators in rational range.