• 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 Radiation Protection and Research
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• v.29 no.1
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• pp.65-71
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• 2004

A multi-attribute utility analysis was investigated as a tool for the decision support of countermeasures in early phase of a nuclear accident. The utility function of attributes was assumed to be the second order polynomial expressions, and the weighting constant of attributes was determined using a swing weighting method. Because the main objective of this study focuses on the applicability of a multi-attribute utility analysis as a tool for the decision support of countermeasures in early phase of a nuclear accident, less quantifiable attributes were not included due to lack of information. In postulated accidental scenarios for the application of the designed methodology, the variation of the numerical values of total utility for the considered actions, e.g. sheltering, evacuation and no action, was investigated according to the variation of attributes. As a result, it was shown that the numerical values of total utility for the actions are distinctly different depending on the exposure dose and monetary value of dose. As increasing in both attributes, the rank of the numerical values of total utility increased for evacuation, which is more extreme action than for sheltering, while that of no action decreased. As expected probability of high dose is higher, the break-even values for the monetary value of dose, which are the monetary value of dose when the ranking of actions is changed, were lower. In audition, as aversion psychology for dose is higher, the break-even values for dose were lower.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.3
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• pp.211-217
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• 2008

Natural environment, topographical conditions and marine traffic flows were investigated and questionnaire surveys were performed for the purpose of understanding the cause of marine accidents. The frequent cases of ships' dragging have happened at the anchorages of E-1, E-2 and E-3. The anchorage area is insufficient for the accommodation of a number of ships, the dolphins at the nearby piers are located near a narrow fairway. SBMs' are positioned too close to the fairway. It shows that many crossing marine traffic flows occur in all areas of the port. Marine casualties are concentrated mainly at No. 1 fairway, M1-M7 waters close to the dolphins and Gwanjeolgot, "E" anchorage and the waters close to the fairway "come and go" areas. The marine traffic flow is mainly caused by the ships' movement at the inter-port and most of the ships are the dangerous cargo carriers. And small ships like the tug-barge are moving disorderly in the ports. Furthermore, the fairway‘s layout is crossing each other. Questionnaire surveys of the users and experts shows that the LANBY that can distinguish the fairway of "come and go" ports is required.

• Journal of Korean Society of Transportation
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• v.23 no.3 s.81
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• pp.125-136
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• 2005

The current traffic accident reduction procedure in economic feasibility study does not consider the characteristics of road and V/C ratio. For solving this problem, this paper suggests methods to be able to evaluate safety of each road in construction and improvement through developing accident Prediction model in reflecting V/C ratio Per road types and traffic characters. In this paper as primary process, model is made by tke object of urban roads. Most of all, factor effecting on accident relying on road types is selected. At this point, selecting criteria chooses data obtained from road planning procedure, traffic volume, existence or non-existence of median barrier, and the number of crossing point, of connecting road. and of traffic signals. As a result of analyzing between each factor and accident. all appear to have relatives at a significant level of statistics. In this research, models are classified as 4-categorized classes according to roads and V/C ratio and each of models draws accident predicting model through Poisson regression along with verifying real situation data. The results of verifying models come out relatively satisfactory estimation against real traffic data. In this paper, traffic accident prediction is possible caused by road's physical characters by developing accident predicting model per road types resulted in V/C ratio and this result is inferred to be used on predicting accident cost when road construction and improvement are performed. Because data using this paper are limited in only province of Jeollabuk-Do, this paper has a limitation of revealing standards of all regions (nation).

• Journal of the Korea Convergence Society
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• v.11 no.2
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• pp.75-83
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• 2020

This study aimed to understand the differences in general characteristics, principal diagnosis, injury-related characteristics, and types of transportation accidents between young-old and old-old patients who were hospitalized owing to injury based on data from the Korean National Hospital Discharge In-Depth Injury Surveys. We used a complex sample cross tabulation analysis (chi-square test) and complex sample generalized linear model (t-test). Therefore, the primary focus of healthcare professionals working with the old-old should prevent falls in the home and increase the available medical care, financial aid plans, and psychosocial support for aging. Additionally education on traffic accident prevention and road safety is particularly important for old-old patients.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.5
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• pp.138-150
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• 2020

Pedestrians are the most vulnerable road users. According to one analysis of traffic accidents over a five year period, pedestrians accounted for about 40% of all road traffic deaths in South Korea. Although some policy and engineering approaches have been taken to reduce and prevent traffic accidents, the annual accident change rate is -0.7%, which is insufficient. This study verifies the effectiveness of presenting visual messages to pedestrians and the effect from adding auditory messages to the visual messages. The experiment was conducted on crosswalks adjacent to an intersection, and safety behaviors were recorded for a total of 898 pedestrians and considered sufficient. As a result of the study, overall pedestrian safety behavior improved when both visual and auditory messages were presented, rather than just visual messages. Therefore, the results indicate it is more effective to provide a mixed visual/auditory form of messages, rather than providing single stimulus messages.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.263-263
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• 2023

블랙아이스는 눈에 쉽게 구분되지 않아 많은 교통사고를 초래하고 있다. 한국교통연구원 교통사고분석시스템에 따르면, 2017년부터 2021년까지 5년간의 서리/결빙으로 인한 교통사고 사망자는 122명, 적설로 인한 교통사고 사망자는 40명으로, 블랙아이스는 적설에 비해 위험성이 높은 것으로 나타난다. 과거의 다양한 연구에서 블랙아이스 생성조건을 기압과 한기 축적등의 조건에서 예측해왔지만, 이러한 기상학적 모델은 봄철 해빙기의 일교차로 인한 눈의 해동과 재냉각과 같은 다양한 기상 조건에서의 블랙아이스 탐지가 어렵다는 한계가 있어 최근에는 이미지 판별과 딥러닝모델(YOLO 등)을 기반으로 한 센서가 제시되고 있다. 그러나, 이러한 방법은 충분한 컴퓨팅 자원이 뒷받침되어야 하며, 블랙아이스 탐지까지 걸리는 속도가 빠르지 못한 편으로, 블랙아이스 초입 구간에서의 제동에 취약하다는 잠재적인 약점을 가지고 있다. 그러므로 본 연구에서는 블랙아이스의 주 원인인 서리나 어는비가 발생하기 위해서 주변 공기가 이슬점 온도 이하, 노면온도와 이슬점이 어는점보다 낮아야 함을 이용, IoT 센서 모듈을 통해 Magnus 방정식으로 계산한 이슬점 온도와 노면 온도를 사용하는 이동식 블랙아이스 추정 장치를 제시한다. 본 장치는 대기압, 온도, 습도로부터 계산된 이슬점 온도와 노면 온도를 통한 서리발생 가능성과 대기 온도, 노면 온도를 통해 어는비의 발생환경 여부를 계산한다. 본 연구 결과를 통해 블랙아이스 추정과 기상정보 생산을 동시에 가능케 하며, 추정 결과를 통합 수집서버에 전송함으로서 운전자에게 전방 블랙아이스 위험 구간을 조기에 전달하는 시스템과 이를 관리하기 위한 인프라를 구축하여 운전 시 결빙 미끄러짐 사고를 저감하고자 한다.

• Journal of the Korean Society of Safety
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• v.29 no.5
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• pp.154-159
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• 2014

This study deals with the pedestrian accidents of intersections in case of Cheongju. The objective is to develop the pedestrian accident models using Tobit regression model. In pursuing the above, the pedestrian accident data from 2007 to 2011 were collected from TAAS data set of Road Traffic Authority. To analyze the accident, Poisson, negative binomial and Tobit regression models were utilized in this study. The dependent variable were the number of accident by intersection. Independent variables are traffic volume, intersection geometric structure and the transportation facility. The main results were as follows. First, Tobit model was judged to be more appropriate model than other models. Also, these models were analyzed to be statistically significant. Second, such the main variables related to accidents as traffic volume, pedestrian volume, number of traffic island, crossing length and the pedestrian countdown signal systems were adopted in the above model.

• Proceedings of the Korea Contents Association Conference
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• 2004.11a
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• pp.501-504
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• 2004

Straight traffic signal information is understanded by roation traffic signal.Ten traffic rotation street flew system saturated without forseed quantaty of traffic vehicle and length oftraffic street.Optimul traffic signal forcasting is needed departmemtstore sale season. for solution of this problem, at least before 10 hour traffic quantity reported policy department.For traffic forcasting of traffic jamed building pushed vehicle, neural network method is adapted Single traffic network is more needed to through traffic signal compared of traffic network. traffic network system is first analysed for artificial traffic network system and networked traffic systen is constructed by ubiquatous.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.333-333
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• 2010

크라이오 펌프는 크기에 비해 상대적으로 큰 배기속도를 가지고 있고 자체 기체 방출이 적어 비교적 쉽고 빠르게 도달압력을 낮출 수 있다. 또 초고진공 펌프로서 경쟁 상대인 터보분자 펌프보다 기체 돌입에 대한 기계적 사고 가능성이 낮다. 그러나 흡착 패널의 온도에 민감하게 반응하는 배기 성능 측면에서 볼 때 크라이오 펌프의 대유량 및 펄스 기체 부하에 대한 성능 유지 및 회복능력은 의문의 여지가 있다. 크라이오 펌프의 기체부하에 대한 공식적인 성능지표로는 최대배기량(max. throughput)과 교차(crossover)값이 있다. 전자는 연속적인 유량[$Pa{\cdot}m^3/s$]에 대해, 또 후자는 일정 기체량[$Pa{\cdot}m^3$]에 대해 흡착 패널이 20 K를 넘지 않는 가동범위를 구하는 것이다. 교차값은 넓은 의미에서 펄스 기체부하에 대한 성능으로 볼 수도 있지만 원래 목적은 진공용기를 저진공 상태에서 고진공 상태로 전환하는 시점을 정하려는 데 있다. 펌프회사에서 제공하는 사양에는 대부분 아르곤 회복시간(Ar recovery time)이라는 지표가 있는데 이는 아르곤을 상당한 유량으로 흘리다 멈췄을 때 얼마나 빨리 기저 상태로 회복되는가를 나타낸다. 보통 사양서에 제시하지는 않지만 주로 크라이오 펌프의 재생상태를 알아보기 위해 사용하는 걸프(gulp) 시험이 있는데 일정량의 기체를 펄스로 도입한 후 압력변화를 기록하여 재생후 배기성능 회복 능력을 보는 것이다. 이들은 겉보기에 서로 다르지만 한편으로는 서로 중복되거나 연관성을 가지고 있어서 실용적인 면에서 절차들을 비교, 검토 및 개선하고 때에 따라서는 적절히 결합할 수 있는 방안을 모색할 필요성이 있다.