• Nuclear Engineering and Technology
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• 제54권12호
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• pp.4534-4550
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• 2022

Integrated severe accident codes should be capable of simulating not only specific physical phenomena but also entire plant behaviors, and in a sufficiently fast time. However, significant uncertainty may exist owing to the numerous parametric models and interactions among the various phenomena. The primary objectives of this study are to present best-practice uncertainty and sensitivity analysis results regarding the evolutions of severe accidents (SAs) and fission product source terms and to determine the effects of mitigation measures on them, as expected during a short-term station blackout (STSBO) of a reference pressurized water reactor (optimized power reactor (OPR)1000). Three reference scenarios related to the STSBO accident are considered: one base and two mitigation scenarios, and the impacts of dedicated severe accident mitigation (SAM) actions on the results of interest are analyzed (such as flammable gas generation). The uncertainties are quantified based on a random set of Monte Carlo samples per case scenario. The relative importance values of the uncertain input parameters to the results of interest are quantitatively evaluated through a relevant sensitivity/importance analysis.

• 한국안전학회지
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• 제32권4호
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• pp.100-106
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• 2017

Outline map is used for the description and reconstruction of the traffic accident. One way to produce the outline map is by adopting detailed measurements from the accident site such as final position of the vehicle and pedestrian, width of the road, and locations of the oil and tire marks. This method consumes large amount of time not to mention that of the production of detailed version as fine as the picture of the site. Aerial recording equipment so called HeliCam can produce an outline map that can substitute that of manual method with even faster production time and higher resolution. However, the produced picture have errors which are resulted by distortion due to the characteristics of camera and direction of the photographing. This paper provides correction of the distortion of oultline map produced by HeliCam using Adobe Photoshop and PC-Rect. The result showed resonable error range less than 6 cm(0.1%) for $60m{\times}30m$ area taken by HeliCam. The presented method develops outline map with small error, which is useful to traffic accident analysis, and traffic accident cases analyzed in this study were also.

• 한국철도학회논문집
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• 제20권4호
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• pp.482-490
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• 2017

본 연구는 사고심각도 분류 및 예측을 위한 철도사고조사 통계기법에 관한 연구이다. 그동안의 선형 회귀분석은 사고 심각도 분석에 어려움이 있었으나 로지스틱회귀분석은 이를 보완할 수 있었다. 데이터마이닝 기법인 로지스틱회귀분석을 활용, 서울지하철(5~8호선) 역사 내 전도사고 중 에스컬레이터 전도사고 발생에 영향을 주는 사고예측 모형 변수는 사고자 연령, 음주여부, 사고 당시상황 및 행동, 핸드레일 잡음 여부였다. 분석의 정확도는 76.7%로 설명되었고 분석방법 결과에 따르면 정확도와 유의수준 측에서 로지스틱회귀분석 방법이 도시철도 사상사고 예측모형을 개발하는데 유용한 데이터마이닝 기법으로 판단된다.

• 한국ITS학회 논문지
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• 제11권6호
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• pp.133-144
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• 2012

본 연구는 교통사고자료를 이용하여 고령자 집단과 비고령자 집단 간의 교통사고요인을 파악하여 각 요인들이 교통사고 심각도에 미치는 영향의 크기를 분석하였다. 나이에 의해 구분된 고령자와 비고령자 집단을 교통사고자료를 이용한 통계학적 방법에 의해 재분류하였으며, 교통사고 심각도에 미치는 영향요인을 분석하기 위해 심각도를 종속변수로 두고, 교통시설, 도로환경, 개인별특성에서 17개 독립변수로 정하여 순서형 로짓모형으로 분석하였다. 고령자 집단과 비고령자 집단의 교통사고 영향요인을 분석하여 비교한 결과, 사고 당사자의 연령뿐만 아니라, 사고유형이나 운전자 개인의 특성, 도로환경도 교통사고에 영향을 미치고 있음이 나타났다. 또한 고령자 집단과 비고령자 집단은 교통사고 심각도에 미치는 영향변수의 종류와 크기가 각각 다른 것으로 나타났다. 이는 각 집단의 개인적 특성에 적합한 교통시설이 개선된다면 교통사고의 심각도를 줄일 수 있음을 의미하는 것이라 할 수 있다.

• 조명전기설비학회논문지
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• 제23권9호
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• pp.91-97
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• 2009

전력케이블 사고 발생시에는 사고원인을 규명 해야하며, 본 연구에서는 FMEA 방법을 이용하여 케이블 사고에 대한 자가원인 진단 시스템을 구축하였다. 자가원인 진단 시스템은 사고당시의 데이터 입력, 픽토그래프를 통한 사고형태의 표현, FMEA 방식을 적용한 사고확률 값으로 구성되어 있으며, 각 선택에 따라 사고원인에 대한 사고가능성이 결과로 나타나게 된다. 또한 실제 케이블 사고사례의 원인분석을 통해 자가원인 진단 시스템을 검증한 결과, 이 시스템은 실제 분석결과와 잘 일치되었다.

• 한국안전학회지
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• 제32권5호
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• pp.96-102
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• 2017

The highest fatal accident ratio was recorded in the construction industry. According to the industrial insurance premium rate & business type example, among the construction industry, the architectural work has the highest fatal and loss time accident ratio. Previous literature has investigated various aspects of accident occurrence and prevention in architectural work. However, those studied were limited in that they only focused on the fatal accident without considering the loss time accident. But non fatal accidents were recorded more than 50 times of fatal accidents. Therefore non fatal accidents must be controlled to lessen industrial accidents. Based on this, the goal of this study was to investigate the nature of the loss time accident and derive the risk index of work type in architectural work. In this study, opinions of safety experts were gathered and the risk index of work type was derived using AHP(Analytic Hierarchy Process). And verification was accomplished by comparing the results of this study with the risk index derived by analysis of accident records. Results showed that the risk index of work type was significantly higher in steel frame work, temporary installation work, earth & foundation work, facilities work, concrete work. And statistical analysis for verification showed that coefficient of Pearson correlation was 0.686 and P-value was 0.001.

• 한국안전학회지
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• 제38권4호
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• pp.15-22
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• 2023

LPG-related accidents, which account for half of all gas accidents in Korea, have not shown any sign of decrease over the past decade, partially owing to the lack of effective safety improvement measures. The purpose of this study was to identify the effectiveness of improvement measures by analyzing the traits of accidents in terms of human factors, and to seek more effective accident prevention strategies. In this study, 108 accident cases were collected and analyzed in the aspect of accident characteristics such as violation type, human factors, and so on. The results showed that the work procedures of suppliers and engineers related to LPG accidents seemed to be similar in outward appearance; however, specific accident causes and unsafe behaviors were different. Particularly, type and target of violations were different, which could be visually confirmed by the Principal Component Analysis (PCA) and the Quantification Techniques (QT). Furthermore, for engineers, insufficient supervision was a major influencing factor. In conclusion, because the accident characteristics of suppliers and engineers are different, differentiated accident prevention strategies should be implemented, which was discussed in this study.

• 자동차안전학회지
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• 제12권3호
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• pp.52-60
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• 2020

Usage of EDR(Event Data Recorder) report for traffic accident analysis is currently increasing due to government regulation of EDR data release. Nevertheless, a lot of investigators simply adopt by comparing the number of ignition cycles(crash) at event to the number of ignition cycles(download) without an exact judgment whether event data occurred by this accident or not. In the EDR report, besides ignition cycles, there are many factors such as event record type, algorithm active(rear/rollover/side/frontal), time between events, event severity status(rollover/rear/right side/reft side/frontal), belt switch circuit status, driver/passenger pretensioner/air-bag deployment, PDOF(Principal Direction of Force) by ΔV to be able to decide whether or not to adopt. also the event data is considered enough to vehicle damaged state, accident situation at the scene of the accident. and there is described in "all data should be examined in conjunction with other available physical evidence from the vehicle and scene" in the CDR(Crash Data Retrieval) report. Therefore many investigators have to decide whether or not to adopt after they consider sufficiently to above factors when they are the traffic accident analysis and investigate the causes of a accident on the adopted event data. In this paper, we report to traffic accident investigators notable points and analysis methods on the basis of thousands of cases and the results of one's own experiment in NFS(National Forensic Service).

• 한국안전학회지
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• 제33권3호
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• pp.58-64
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• 2018

Recently, a lot of accident report documents have accumulated in almost all of industries, including critical information of accidents. Accordingly, text data contained in accident report documents are considered useful information for understanding accident processes. However, there has been a lack of systematic approaches to analyzing accident report documents. In this respect, this paper aims at proposing text analytics approach to extracting critical information on accident processes. To be specific, major causes of the accident occurrence are classified based on text information contained in accident report documents by using both textmining and latent Dirichlet allocation (LDA) algorithms. The textmining algorithm is used to structure the document-term matrix and the LDA algorithm is applied to extract latent topics included in a lot of accident report documents. We extract ten topics of accidents as accident types and related keywords of accidents with respect to each accident type. The cause-and-effect diagram is then depicted as a tool for navigating processes of the accident occurrence by structuring causes extracted from LDA. Further, the trends of accidents are identified to explore patterns of accident occurrence in each of types. Three patterns of increasing to decreasing, decreasing to increasing, or only increasing are presented in the case of a chemical plant. The proposed approach helps safety managers systematically supervise the causes and processes of accidents through analysis of text information contained in accident report documents.

• 한국보건간호학회지
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• 제14권2호
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• pp.332-341
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• 2000

Children's accident is a largely preventable public health problem. Little is known. however, about population-based incident and outcome of pediatric accident. From 1997.9 through 1998,8. admission data from emergency center in I city were collected. 1418 patient from 0 through 13 years of age were selected. All children with unintensional accidental problems were identified through coded sheet which categorizes epidemiologic characteristics. The specific purposes of this study are analysis about the characteristics of pediatric accidents. And it aims to produce the basic data necessary for accident prevention policy development. The results of this study were as follows; 1. The number of male children$(62.6\%)$ were higher than female children$(37.4\%)$ 2. The age group from 1 to 3 years represents the highest proportion$(45.4\%)$ of every accidents except on traffic accident. 3. The highest proportion of accident were as follows occured during the June-August$(34\%)$, Sunday$(22.6\%)$, and 17-21 p.m. $(37.2\%)$ 4. The main causes of accident include general trauma$(70.9\%)$, environmental accident$(l6.8\%)$. and traffic accident$(l2.1\%)$, 5. Preschool age group represents more than half$(65.4\%)$ of traffic accident. 6. environmental injury includes burns $(46.6\%)$, foreign body$(43.6\%)$, exposure to poisonous materials$(6.3\%)$. and bite(3.3) This results could be used to develope prevention programs and assist in accident prevention system development. And also these data substantiate that accident prevention program decrease safety-related injury rate in preschool age group must be concentrated on enhancing access to a system to have a significant effect. Furthermore, it is necessary for accident prevention. So several suggestions are described here: 1. Development of parent's educational program for accident prevention and safety education should be done actively. 2. Home safety surveillance system should be initiated. 3. The initiation of children's accident report system could be contribute the analysis and the reduction of accident.