• 한국도로학회논문집
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• 제19권4호
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• pp.61-68
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• 2017

PURPOSES : A complete signal system is not always the best solution for improving traffic operation efficiency at intersections. An alternative solution is to use a Protected Permitted Left Turn (PPLT) operation method. However, the PPLT method needs to be developed after a detailed study of driving tendencies, most notably the gap acceptance behavior, for successful implementation. In this study, the gap acceptance behavior was investigated under various variables and weather conditions, especially under rain, and the results were compared to the case of normal weather. The results of this study will be helpful in introducing the PPLT method, and are important considering the tendency of attempting unprotected left turns that is extremely common in Korean drivers. METHODS : Data was obtained by analyzing traffic footage at four intersections on a day when the precipitation was greater than 5 mm/h. The collected data was classified into seven variables for statistical analysis. Finally, we used logistic regression analysis to develop a probability distribution model. RESULTS : Gap, traffic volume, and the number of conflicting lanes were factors affecting the gap acceptance behavior of unprotected left turns under rainy conditions. CONCLUSIONS : The probability of attempting unprotected left turns is higher for larger gaps. On the other hand, the probability of attempting unprotected left turns decreases with an increase in the traffic volume. Finally, an increase in the number of conflict lanes leads to a decrease in the probability of attempting unprotected left turns.

• 한국전자거래학회지
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• 제18권4호
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• pp.215-240
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• 2013

본 논문은 기업의 모바일 보안기술 도입에 영향을 미치는 특성요인에 관한 이론적 설명력을 제고하기 위해 채택연구들의 이론적 기반이 되었던 혁신확산이론, 혁신저항모델, 기술수용 모델, 정보자산보호 활동이 제시하고 있는 주요 구성개념, 실증연구결과들을 검토하였다. 모바일 보안기술 도입을 위한 특성요인들과 이용의사에 미치는 영향을 검증하기 위해 본 연구모형에서 제시한 17개의 연구가설을 구조방정식모델 분석방법을 사용하여 실증적으로 검증하였다. 연구 결과, 첫째, 혁신저항에 가장 큰 영향을 미치는 모바일 보안기술 특성요인 들은 '적합성', '복잡성', '상대적 이점', '정보자산보호' 순으로 나타났다. 둘째, 이용의사에 영향을 미치는 특성요인은 '상대적 이점', '적합성', '혁신저항', '성과기대'인 것으로 나타났다. 이는 향후 모바일 보안기술 채택 연구의 이론적 배경을 제공하는데 의의가 있으며, 검증된 특성요인 들은 확산주체에게 기존 보안기술과 새로운 모바일 보안기술 간의 정보격차를 완화시키는 정책방향이나 모바일 보안기술도입을 위한 전략적 차원의 시사점을 제공한다.

• 대한토목학회논문집
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• 제34권2호
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• pp.573-582
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• 2014

교차로에 인접한 부 도로에 대한 설치기준이 명확하지 않아 설치 및 운영에 많은 문제점을 야기시키고 있으며, 이로 인하여 교통소통과 교통안전에 문제가 발생하고 있다. 현재까지 교차로 진출입과 관련하여 운영적인 측면에서는 많은 연구가 시도되었지만, 교차로에 인접한 부 도로에 대한 연구는 대단히 미흡하고 이에 따른 합리적인 설계가 이루어지지 못하는 실정이다. 이에 본 연구에서는 교차로에 인접한 부 도로에서 진출하는 차량에 대한 행태를 조사하고, 교통소통과 안전을 고려하여 교차로에 인접한 부 도로의 적절한 이격거리를 제시하고자 한다. 교통소통과 안전을 도모할 수 있는 교차로에 인접한 부 도로의 적정길이를 제시함으로써, 향후 교차로에 인접한 부 도로와과 관련된 설치기준 정립에 이바지하고자 한다.

• 대한교통학회:학술대회논문집
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• 대한교통학회 1996년도 제29회 학술발표회
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• pp.59-86
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• 1996

Current methods for evaluating unsignalized intersections, and estimating level-of-service (LOS) is determined from efficiency-based criteria such as little or no delay to very long delays. At present, similar procedures to evaluate intersections using safety-based criteria do not exist. The improvement of sight distances at intersections is the most effective way of improving intersection safety. However, a set of procedures is necessary to account for the limitations in current methodology. Such an approach would build upon such methods, but also account for: deficiencies in the current deterministic solution for the determination of intersection sight distances; opportunity for an accident and severity of an accident; and cost-effectiveness of attaining various levels of sight distances. In this research, a model that estimates the degree of safety at two-way stop-controlled intersections is described. Only crossing maneuvers are considered in this study because accidents caused by the crossing maneuvers are the dominate type among intersection accidents. Monte Carlo methods are used to estimate the hazard at an intersection as a function of roadway features and traffic conditions. Driver`s minimum gap acceptance in the crossing vehicles and headway distribution on the major road are used in the crossing vehicles and headway distribution on the major road are used in the model to simulate the real intersectional maneuvers. Other random variables addressed in the model are: traffic speeds; preception-reaction times of both drivers in the crossing vehicles and drivers in oncoming vehicles on the major road; and vehicles on the major roads. The developed model produces the total number of conflicts per year per vehicle and total potential kinetic energy per year per vehicle dissipated during conflicts as measurements of safety at intersections. Based on the results from the developed simulation model, desirable sight distances for various speeds were determined as 350 feet, 450 feet and 550 feet for 40 mph, 50 mph and 60 mph prevailing speed on the major road, respectively. These values are seven to eight percent less than those values recommended by AASHTO. A safety based level-of-service (LOS) is also developed using the results of the simulation model. When the total number of conflicts per vehicle is less than 0.05 at an intersection, the LOS of the intersection is `A' and when the total number of conflicts per vehicle is larger than 0.25 at an intersection, the LOS is `F'. Similarly, when the total hazard per vehicle is less than 350, 000 1b-ft2/sec2, the LOS is `F'. Once evaluation of the current safety at the intersection is complete, a sensitivity analysis can be done by changing one or more input parameters. This will estimate the benefit in terms of time and budget of hazard reduction based upon improving geometric and traffic characteristics at the intersection. This method will also enable traffic engineers in local governments to generate a priority list of intersection improvement projects.