• 대한교통학회지
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• 제28권3호
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• pp.169-183
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• 2010

영상기반의 교통정보수집시스템은 관리 및 운영상의 한계를 보이고 있는 기존의 루프검지기의 역할을 대체하는 검지기로써의 역할 뿐만 아니라 다양한 교통류의 정보를 제공하고 관리할 수 있으며, 교통사고의 발생전과 후의 순차적인 상황을 정확히 기록하고, 이 자료를 통해 발생된 교통사고의 사고 매커니즘을 객관적이고 명확하게 조명하고 분석하는 것은 교통사고 처리에 있어서 중요한 부분을 차지함으로서, 여러 나라에서 보급 활용되고 있다. 본 논문에서는, 기존 기술들이 연속류 도로의 특성인 속도변화, 교통량 변화, 점유율 변화와 같은 교통류 흐름을 반영하여 1차 예비판단을 실시하였다. 또한, 1차 예비판단된 경우 영상추출 및 처리를 통해 최종 사고판단을 실시하게 된다. 이 때, 도로상의 다양한 환경적 변화로 인해 극복하기 어려운 차량의 객체추출, 객체분리, 추적 등의 정확성을 확보하기 위해서 계산속도와 정확도 측면에서 우수함을 보이고 있는 Adaptive GMM(Gaussian Mixture Model) 기반으로 실시하였으며, 환경적인 요인으로 인해 자주 발생하고 있는 오 검지 상황들을 효과적으로 저감시킬 수 있는 능동적이고 환경적응적인 기법을 통해 사고 최종판단을 실시하였다. 이렇게 구현된 기술의 성능을 평가하고자 중부내륙 실험도로에서 12건의 사고 모의실험을 실시하였으며, 실제 운용되고 있는 장항IC에서의 사고영상을 실시간 온라인으로 입력받아 시험하였다. 결과적으로, 검지율 93.33%, 오검지 6.7%로 높은 신뢰성을 보였다.

• Journal of Radiation Protection and Research
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• 제47권2호
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• pp.77-85
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• 2022

Background: After the Fukushima Daiichi Nuclear Power Station (FDNPS) accident, a model was developed to estimate the external exposure doses for residents who were expected to return to their homes after evacuation orders were lifted. However, the model's accuracy and uncertainties in parameters used to estimate external doses have not been evaluated. Materials and Methods: The model estimates effective doses based on the integrated ambient dose equivalent (H^*(10)) and life patterns, considering a dose reduction factor to estimate the indoor H^*(10) and a conversion factor from H^*(10) to the effective dose. Because personal dose equivalent (H_p(10)) has been reported to agree well with the effective dose after the FDNPS accident, this study validates the model's accuracy by comparing the estimated effective doses with H_p(10). The H_p(10) and life pattern data were collected for 36 adult participants who lived or worked near the FDNPS in 2019. Results and Discussion: The estimated effective doses correlated significantly with H_p(10); however, the estimated effective doses were lower than H_p(10) for indoor sites. A comparison with the measured indoor H^*(10) showed that the estimated indoor H^*(10) was not underestimated. However, the H_p(10) to H^*(10) ratio indoors, which corresponds to the practical conversion factor from H^*(10) to the effective dose, was significantly larger than the same ratio outdoors, meaning that the conversion factor of 0.6 is not appropriate for indoors due to the changes in irradiation geometry and gamma spectra. This could have led to a lower effective dose than H_p(10). Conclusion: The estimated effective doses correlated significantly with H_p(10), demonstrating the model's applicability for effective dose estimation. However, the lower value of the effective dose indoors could be because the conversion factor did not reflect the actual environment.

• 한국ITS학회 논문지
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• 제10권4호
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• pp.44-54
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• 2011

첨단도로 안전시설물, 첨단교통관리기법 등을 기반으로 하는 다양한 첨단 교통서비스는 교통사고 등의 돌발상황을 감소시킬 것으로 예상되며, 이에 따라 도로의 지 정체 역시 감소될 것이다. 따라서 안전성 향상에 따른 지 정체 감소효과를 편익항목에 포함시킬 수 있다. 그러나 현재 우리나라의 투자평가지침에서는 이를 편익으로 계상하지 않고 있다. 스마트도로에서 제공하는 첨단 교통서비스는 인프라의 초기 투자비용을 상승시키지만 새로운 서비스로 인한 편익이 계상되지 않아 비용/편익 분석 시에 경제성을 확보하지 못하는 문제점을 가지게 된다. 따라서 본 연구는 과거 3년간의 고속도로 사고 자료를 이용하여 평균 차로차단시간을 추정하고, 미시적 시뮬레이션을 이용하여 구축된 자료와 회귀분석기법을 통해 지체시간 추정모형을 개발하였다. 또한 개발된 모형이 투자평가기법에 적용될 수 있도록 계량화에 필요한 원단위(평균용량감소비율 등)를 제시하였다. 개발된 방법론을 스마트하이웨이사업 사례에 적용 결과, 스마트 안전시설로 인한 사고감소율을 10%로 가정하였을 경우, 30년 동안 총 안전성 향상 편익은 1,392억 원에 이르는 것으로 분석되었다.

• 대한교통학회지
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• 제28권5호
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• pp.155-162
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• 2010

교통사망사고중, 고령자 교통사고가 30%이상을 차지하고 있으며, 해마다 증가추세인 고령 노인교통사고와 관련, 고령화사회에 진입한 현실을 반영하여, 향후 특단의 대책을 수립해야할 필요성이 절박한 실정이다. 본 연구에서는 노인 고령자들이 주로 지방도시 지역의 지방부도로 주변에 밀집거주 및 이동하는 현실을 착안하여 지방부도로 고령보행자사고 특성을 분석하고, 이에 따른 사고심각도 모형을 개발하는 데 주안점을 두었다. 경찰청 교통사고자료를 720건 입수하여, 경상 중상 사망등 가중치를 반영한 사고심각도 모형을 중회귀분석에 의해 도출하였으며, 그 결과 사고심각도에 가장 영향력이 큰 독립변수는 역시 과속차량임을 통계적으로 입증할 수 있었다.

• 한국ITS학회 논문지
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• 제13권6호
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• pp.54-63
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• 2014

우리나라 교통사고의 심각성은 OECD 회원국 평균보다 굉장히 높은 수준이며 보행자 사고는 이보다 더 심각한 상황이다. 그럼에도 불구하고 경찰청은 야간의 불필요한 신호대기를 최소화하고 운전자의 운전편의를 개선하기 위하여 점멸신호운영을 확대하고 있는 추세이다. 비록 경찰청은 점멸신호운영이 사고감소에도 긍정적인 영향을 미친다고 발표하고 있지만, 대부분의 해외연구들은 이와는 상반되는 결과를 제시하고 있다. 본 연구에서는 서울시내 54개 점멸신호 운영 교차로를 대상으로 점멸신호운영이 교통사고에 미치는 영향을 분석하고 이에 대한 개선방안을 제시하였다. 분석자료는 점멸신호가 운영되고 있는 교차로의 3년(2011~2013) 동안 사고자료와 사고에 영향을 미칠 것으로 판단되는 교통량과 교차로 기하구조(교차로면적, 좌회전차로, 차선수 등)를 바탕으로 하였다. 평균보다 분산이 큰 교통사고자료의 고유특성을 반영하기 위하여 음 이항 회귀모형(Negative Binomial Regression Model)을 사용하였으며, 모형구축 결과 보행과 연관된 횡단보도 면적 및 버튼식 보행신호기 개수가 사고와 밀접한 연관이 있는 것으로 나타났다. 또한 기존 연구결과와는 달리 일반신호운영교차로에 비해 점멸신호운영교차로의 사고안전성이 더 취약한 것으로 분석되었으며, 그 격차는 약 9% 정도로 나타났다.

• 한국안전학회지
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• 제31권3호
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• pp.143-155
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• 2016

Recently, a massive loss of life and property is occurring in Korea due to traffic accidents, with the rapid increase in cars. For improvement of traffic safety, the Korea Transportation Safety Authority intensively analyzes accident data in local governments with low traffic safety index, performs a field investigation to extract problems and offers local governments improvements for problems, by conducting the 'Special Survey of Actual Conditions of Traffic Safety' each year, starting 2008. But local governments cannot strongly push forward the improvement projects due to the limited budget and the uncertainty of the improvement plan effects. Therefore, this study suggested a model which applied the Utility concept to the AHP theory, in order to efficiently decide a priority of the improvement plans in accident black spots in consideration of the limited budget of local governments. The number of accidents in each spot for improvement and accident severity, traffic volume, pedestrian volume, the improvement project cost and the accident reduction effect were chosen as evaluation factors for deciding a priority, and data about the improvement plan costs and the accident reduction effects, traffic accidents and traffic volume in the spots to undergo the special research on the real condition of traffic accident in the past were collected from the existing studies. Then, regression analysis was carried out and the Utility Curve of each evaluation factor was computed. Based on the AHP analysis findings, this study devised a priority decision method which calculated the weight and the utility function of each evaluation factor and compared the total utility values. The AHP analysis findings showed that among the evaluation factors, accident severity had the biggest importance and it was followed by the improvement plan cost, the number of accidents, the improvement effect, traffic volume and pedestrian volume. The calculated utility function shows a rise in utility, as the variables of the 5 evaluation factors; the number of accidents, accident severity, the improvement plan effect, traffic volume and pedestrian volume increase and a fall in utility, as the variables of the improvement plan cost increase, since the improvement plan cost is included in the budget spent by a local government.

• 대한교통학회지
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• 제23권3호
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• pp.49-57
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• 2005

본 연구에서는 보행자와 차량의 충돌 시 보행자의 상해를 감소시키기 위한 충돌안전기준의 도입에 따른 보행자 사망자수 감소 효과를 추정하는 방법론을 개발하였다. 국내 교통환경 특성을 반영한 보행자 사망확률모형을 개발하고, 사망자 감소 효과 추정에 반영하였다. 사고재현을 통해 추정된 충돌속도를 보행자 사망확률모형의 주요 변수로 사용하였다. 모형의 개발을 위해서는 logistic regression 기법을 적용하였으며, 충돌안전기준의 주요 변수인 HIC(Head Injury Criterion)와 충돌속도의 변화에 따른 사망자수 감소효과를 계량화하여 제시하였다. 제안된 방법론은 향후 국내 실정에 부합되는 충돌안전기준의 개발, 보행자 보호를 위한 첨단 차량의 개발, 보행자 안전을 위한 정책 수립 등을 지원하는 중요한 역할을 수행할 것으로 기대된다.

• Journal of Radiation Protection and Research
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• 제44권4호
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• pp.128-148
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• 2019

Massive environmental monitoring has been conducted continuously since the Fukushima Daiichi Nuclear Power accident in March of 2011 by different monitoring methods that have different features together with migration studies of radiocesium in diverse environments. These results have clarified the characteristics of radiological environments and their temporal change around the Fukushima site. At three months after the accident, multiple radionuclides including radiostrontium and plutonium were detected in many locations; and it was confirmed that radiocesium was most important from the viewpoint of long-term exposure. Radiation levels around the Fukushima site have decreased greatly over time. The decreasing trend was found to change variously according to local conditions. The air dose rates in environments related to human living have decreased faster than expected from radioactive decay by a factor of 2-3 on average; those in pure forest have decreased more closely to physical decay. The main causes of air dose rate reduction were judged to be radioactive decay, movement of radiocesium in vertical and horizontal directions, and decontamination. Land-use categories and human activities have significantly affected the reduction tendency. Difference in the air dose rate reduction trends can be explained qualitatively according to the knowledge obtained in radiocesium migration studies; whereas, the quantitative explanation for individual sites is an important future challenge. The ecological half-lives of air dose rates have been evaluated by several researchers, and a short-term half-life within 1 year was commonly observed in the studies. An empirical model for predicting air dose rate distribution was developed based on statistical analysis of an extensive car-borne survey dataset, which enabled the prediction with confidence intervals. Different types of contamination maps were integrated to better quantify the spatial data. The obtained data were used for extended studies such as for identifying the main reactor that caused the contamination of arbitrary regions and developing standard procedures for environmental measurement and sampling. Annual external exposure doses for residents who intended to return to their homes were estimated as within a few millisieverts. Different forms of environmental data and knowledge have been provided for wide spectrum of people. Diverse aspects of lessons learned from the Fukushima accident, including practical ones, must be passed on to future generations.

• 대한안전경영과학회지
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• 제10권3호
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• pp.43-53
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• 2008

This study is carried out for the fire safety of the factory building, the fire risk reduction measure in compliance with an example approached in fire risk reduction systematically, contribute to reduce the fire risk. The analytical fire risk process of discovering, identifying, estimating and evaluating risk and control measure as risk reduction measures are core concept, applies loss prevention with loss control techniques. The painting process in the workplace where the fire hazard and death accident accompanies coexists. Loss prevention problem of creation prevention of dangerous atmosphere at workplace is health and human services problem of normal circumstances, must be inspected with problem of combustible gases at the time of fire explosion. Static electricity measure accomplished the risk control process thoroughly as the fire risk reduction process model with the ignition sources measure which is presented. Fire risk from within organizing will be able to classify with each field by detailedly but risk treatment process will be able to apply basically all the same concept. Consequently about risk management example from before, this study is proposed risk management techniques that standardized rightly in the actual condition of organization with one plan, with discovery of fire risk, the feedback process in compliance with a fire risk reduction and the review which control the result is joint responsibility of engineer, technical expert and manager as part of safety management to practice with the fact must be supervised.

• 대한교통학회지
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• 제5권2호
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• pp.55-72
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• 1987

The work analyzes the existing situation and defines special problems concerning traffic accidents in the two countries. The report is divided into three parts: 1) Using the global approach of SMEED, the data were evaluated using multiple regression analysis, and homogeneous groups of countries were defined by cluster analysis. In the global approach, the linear model is better than SMEED's non-linear model in explaining the number of fatalities. Among the different groups of countries, the linear approach was found to be better suited for industrialized countries and the non-linear approach better for the developing countries. T도 comparison of traffic fatality data for the Federal Republic the developing countries. The comparison of traffic fatality data for the Federal Republic of Germany and the Republic of Korea showed different regression equations during the same time period. 2) The BOX/JENKINS time series analysis on a monthly basis points out clearly similar seasonal patterns for the two countries over the years studied. The decrease in traffic accidents following the intensification of the safety belt requirement was proved in the ARIMA model. It amounts to 7 to 8 percent fewer personal injury accidents and fatal accidents. The identified increase in safety in the Federal Republic of Germany since the 1970s is mainly due to the reduction of accident severity in residential areas. 3) Speeds and headways on motorways in th3e two countries were also compared. The measurements point out that German road users drive faster, take more risks, and accept shorter time gaps than Korean road users. However, the accident statistics show accident rates for Korea that are several times higher than those in the Federal Republic of Germany.