• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.2
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• pp.273-279
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• 2019

Development of mountain area is increasing due to the demand for improvement of traffic convenience and development of underdeveloped area. Therefore, there frequently are sections where tunnels and interchanges are located close to each other. These sections do not only affect tunnel planning, types and length of interchanges, but also affect more on route selection. In Korea, several design criteria present each reference value but these values are very similar. In the situation, the minimum value among them is usually applied when planning roads and it could cause traffic safety problems in different site conditions. In this study, the problems of design speed, illuminance adaptation distance, and lane change intervals are analyzed by simulating the cases that the problem could occur when calculating the separation distance between tunnel and interchange. The results obtained from this study can be summarized as following: the driving speed should be applied in case that the site has a big gap between design speed and driving speed because the uniform application of the design speed is not safe; the illuminance adaptation distance should include the influence distance in the section affected by the direct light; in addition, the lane change distance should include the time to perceive the situation of the next lane after the lane change in the section required for successive lane change.

• Tunnel and Underground Space
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• v.18 no.6
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• pp.491-502
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• 2008

A certain range of the original ground around the tunnel should be preserved to ensure structural safety of the tunnel when other structures are made around the tunnel, and thus this range is defined as safety zone of the tunnel. The main points to ensure the stability of an existing tunnel when constructing a new tunnel in an inter-crossing area are distance between two tunnels, size of the new tunnel, excavation method for the new tunnel, ground condition around the tunnel, and lining type of the existing tunnel etc. When the new tunnel is excavated above the existing tunnel, the existing tunnel is likely to suffer deformation at a crown zone, damage of arching effect, and live load of the new tunnel etc. On the other hand, when the new tunnel is excavated below the existing tunnel, the existing tunnel is likely to be damaged due to settlement. This study has been made on the behavior of the existing tunnel by means of model test and numerical analysis when the new tunnel is excavated below the existing tunnel. Safety zone of the tunnel was estimated by the results of strength/stress ratio obtained from numerical analysis, and the movement of ground was estimated by the model test. The results of earth pressure, ground displacements, and convergence of the tunnel obtained from model test were compared with those of numerical analysis, and show a similar trend.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.2
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• pp.1-11
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• 1984

This aims of this study is to analyse the correlationship between traffic accident s and traffic characteristic variables in at-grade intersections of urban area, to build up an accident forecasting model and to propose an evaluation method of hazardous at-grade intersections. The accident forecasting model is formulated by the use of residual indexes that is selected by principal component analysis and its statistical significance is tested by step-wise regression analysis. Effective countermeasures for safety can be established on the basis of identifying high accident intersections, because the validity of this model was examined and found to coincide with real world situations.

• Journal of Korean Society of Transportation
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• v.22 no.4 s.75
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• pp.31-42
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• 2004

This study develops Accident Modification Factors (AMF) of countermeasures with Baysian method which are newly proposed for reducing Roadway-Rail grade crossing accidents. This study proposes a new "Bayesian Analytical Framework" for countermeasure assessment which combines "Subjective" Prior Information with "Logical" based Information. The newly proposed "Bayesian Analytical Framework" consists of the following three steps: The 1st step - Countermeasure Selection, Choice of Participants, Selection of Crashes; The 2nd step-Development of Crash History Manual and Countermeasure Evaluation Manual; The 3rd step-Development of AMFs through sound statistical tests. This study used the Komogorov-Smirnov(K-S) Test to determine whether two unknown distribution functions associated with the two populations are identical. The results of the study are that individual responses did not meet the K-S test of identical distributions. while individual vs. group distributions are identical. This indicates that combining the input of several people reduces the impact of individual subjectivity and assumptions and is important for developing a repeatable distribution to develop sound AMFs of countermeasures for reducing Roadway-Rail grade crossing accidents. The procedures of the AMF development conducted in this study can be used to estimate the safety effects of countermeasures for road segments and intersections, in addition to Roadway-Rail grade crossings.

• Journal of Korean Society of Transportation
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• v.23 no.1
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• pp.33-44
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• 2005

Railroad crossing crashes are fewer than road crashes, but with regard to crash severity, they can be serious injury crashes. There should be, therefore, enormous efforts to increase the safety of railroad crossings. The objective of this paper is to identify and understand factors associated with railroad crossing crashes. Statistical models are used to examine the relationships between crossing accidents and geometric elements of crossings. The results show the Poisson model is the most appropriate method for the crossing accidents, because overdispersion was not observed. This study identifies seven significant factors associated with railroad crossing crashes through the main and variant models. With regard to explanatory factors on crossing safety, the total traffic volume, daily train volume, presence of commercial area around crossings, distance of train detector from crossings, time duration between the activation of warning signals and gates, crossing types, and speed hump were found to affect the safety of railroad crossings.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.649-655
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• 2021

This study purposes to cross-validate its performance by applying the optimal seismic vulnerability assessment model based on previous studies conducted in Gyeongju to other regions. The test area was Pohang City, the occurrence site for the 2017 Pohang Earthquake, and the dataset was built the same influencing factors and earthquake-damaged buildings as in the previous studies. The validation dataset was built via random sampling, and the prediction accuracy was derived by applying it to a model based on a random forest (RF) of Gyeongju. The accuracy of the model success and prediction in Gyeongju was 100% and 94.9%, respectively, and as a result of confirming the prediction accuracy by applying the Pohang validation dataset, it appeared as 70.4%.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2016.11a
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• pp.261-262
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• 2016

교통사고의 발생요인에는 다양한 원인들이 있지만 본 연구에서는 공간적으로 접근하여 사고유형별 분포특성을 도출하기 위해 공간적 자기상관성 분석을 수행하였다. 논문에서는 2012년부터 2014년까지 울산광역시에서 발생된 교통사고를 대상으로 분석을 수행하였다. 그 결과 울산시 전체 교통사고 약 53%는 안전운전불이행이며 다음으로는 안전거리미확보, 신호위반 순으로 나타났다. 밀도분석 결과는 사고유형별로 분포가 차이가 있었으며 안전운전불이행의 경우 가장 큰 군집은 중심시가지인 달동과 삼산동 중심에 나타났으며 중앙선침범은 도시의 중심부 보다는 면지역에 넓게 퍼져서 발생되었으며 산업단지가 있는 동구지역에 군집이 크게 나타났다. 따라서 읍면동별 공간적 특성을 파악하기 위해 Moran's I분석과 LISA분석을 수행한 결과 안전운전불이행, 안전거리미확보, 신호위반, 교차로운행방해 모두 중심시가지인 신정동, 달동, 삼산동이 공간적 자기상관성이 높았으며 중앙선침범의 경우 밀도분석 결과와 마찬가지로 중심시가지 이외에 읍면 지역도 자기상관성이 더 높게 나타났다. 이를 통해 사고유형별 공간의존성 및 이질성을 파악하여 교통사고 다발지역을 도출하고 이를 토대로 지역특성에 맞는 저감 대책 마련에 활용되고자 한다.

• Journal of Korean Society of Transportation
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• v.16 no.1
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• pp.47-58
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• 1998

자동차 항법장치의 디스플레이는 도로, 교통정보, 부가정도 등 ITS 정보를 운전자에게 직접전달 하는 부분으로 그 핵샘부품인 도로지도는 정보의 정확성 및 신뢰성의 획득과 함께 운전자의 안전 및 수 행도 향상 항법장치의 사용성 향상을 위하여 운전자가 쉽고 빠르고 정확하게 자신이 원하는 정보를 획 득할 수 있도록 운전자 중심의 설계가 실시되어야 한다. 이에 97년 G7 Navigation 시스템 제작기술 프 로젝트의 일환으로 실시된 본 연구는 지도의 회전방법(map-rotation)방법인 Heading-Up 및 North-Up 과 지도상 지형지물 명칭 문자정보의 회전(text-rota-tion)을 실험변수로 하여 운전자의 반응시간 에러발 생 정신적부하의 측면에서 교차로 유형별 지도진행방법에 따른 인간공학적 평가를 실시한다. 본 연구의 결과로 한국인의 정보인지 형태에 적합한 항법장치 도로지도 진행방법을 제시하며 각 진행방법의 특징 및 운전자의 정보인지에 영향을 주는 요인을 추출한다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.249-250
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• 2017

현재 전체 교통사고 건수는 감소하는 추세이지만 보행자 교통사고는 점점 증가하고 있다. 또한 보행자 교통사고 중 고령보행자 교통사고건수 비율이 높은데 이에 따른 원인분석과 예방 대책에 관한 연구가 필요하다. 이에 본 연구는 고령보행자 다발지역을 분석하여 사고 원인을 비교분석 하는 것이다. 다발지역 분석결과 대부분 보행자가 횡단 중 일 때 사고가 발생하였고, 도로형태에서는 교차로, 신호기가 없는 일반도로에서 많이 발생했다. 이에 무단횡단을 방지하는 시설 확대 설치와, 무단횡단의 위험성을 알리는 안전교육의 필요성이 있다고 본다.

• Journal of Food Hygiene and Safety
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• v.20 no.3
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• pp.147-158
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• 2005

A food safety survey was conducted to assess the housewives' handling practices and consumption of potentially risky foods in family home. More than $40\%$ of the respondents wash their hands without soap or use their wash towels after contact with potentially risky foods such as meat, poultry, fish, shellfish, raw eggs, meat processed foods, raw fruits and vegetables. Over half of the respondents have consumed undercooked eggs without recognizing the potential health risk of consumption of raw eggs. $34\%$ of the respondents do not wash their hands after breaking raw eggs, indicating high risk of cross contamination while handling raw eggs. More than $60\%$ of the respondents just use running water to wash fresh fruits and vegetables. $78.9\%\;and\;45.2\%$ of the respondents have consumed sushi/sashimi or raw oysters, respectively in the past 12 months. The results of this study indicate the substantial risks of unsafe food-handling practice at the points of cross-contamination, cooling practices, storage time, and consumption of potentially risky foods at home. Considering the housewives' participation in school food service, development of food safety education program for the housewives is needed to promote safe handling practices of potentially risky foods.