• 한국지진공학회논문집
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• 제27권6호
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• pp.237-244
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• 2023

This study analyzes the seismic response of traffic light poles, considering soil-foundation effects through nonlinear static and time history analyses. Two poles are investigated, uni-directional and bi-directional, each with 9 m mast arms. Finite element models incorporate the poles, soil, and concrete foundations for analysis. Results show that the initial stiffness of the traffic light poles decreases by approximately 38% due to soil effects, and the drift ratio at which their nonlinear behavior occurs is 77% of scenarios without considering soil effects. The maximum acceleration response increases by about 82% for uni-directional poles and 73% for bi-directional poles, while displacement response increases by approximately 10% for uni-directional and 16% for bi-directional poles when considering soil-foundation effects. Additionally, increasing ground motion intensity reduces soil restraints, making significant rotational displacement the dominant response mechanism over flexural displacement for the traffic light poles. These findings underscore the importance of considering soil-foundation interactions in analyzing the seismic behavior of traffic light poles and provide valuable insights to enhance their seismic resilience and safety.

• 한국항해항만학회지
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• 제34권5호
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• pp.397-404
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• 2010

현재 부산 북항과 부산 신항간의 컨테이너 환적화물의 대부분은 육상을 통하여 운송되고 있으며, 일부 환적화물은 바지선(barge)을 통하여 해상으로 운송되고 있는 실정이다. 본 연구는 녹색물류의 관점에서 부산 북항과 신항간의 환적 컨테이너의 바지선 운송수요가 증가될 것을 예상하여, 바지선 운송의 타당성을 분석해 보고자 하였다. 부산항 환적물동량의 북항과 신항간 바지선 운송에 영향을 미치는 요인들을 고려하여 연간 수익성을 예측함으로써 북항과 신항 간의 컨테이너 물동량의 바지선 운송 사업의 타당성을 분석하였다. 부강과 신항간의 환적 물동량 변동 시나리오를 사용하여 환적 운송물동량의 50%, 60%, 80%, 100% 운송의 경우와 바지선 월간 항차수 25회를 가정하여, 시나리오별 효과를 예측하였다. 바지선 운송사업은 북항과 신항 간의 TEU당 운임과 항차수에 따라 당기순이익이 좌우되는 것으로 나타났다. 따라서 바지선 운송 사업의 당기순이익이 흑자를 유지하기 위해서는 예상되는 최저 환적물동량이 확보되어야 하고 TEU 당 최저운임이 결정되어야 한다. 본 연구는 전세계적으로 녹색물류가 강화되는 시점에서 부산 북항과 신항간 환적 컨테이너의 바지선 운송 필요성을 제안하여 환경오염과 도시교통 체증 등의 사회적 비용감소에 기여하고자 하였다.

• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1492-1501
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• 2015

This paper analyzes the effect of voltage sag on distribution systems due to the connection of Electric Vehicles (EVs). In order to study the impact of the voltage sag on the power system, two scenarios have been selected in this paper. The distribution system and EVs are modeled using the Electro Magnetic Transients Program (EMTP). The numbers of EVs are predicted based on the number of vehicles in distribution system of Seoul. In addition, the number of EVs is set up using real-time traffic in Seoul to simulate Scenario I and II. The simulation results show that voltage sag can occur if the distribution system has more than 30% of the total number of vehicles.

• 자동차안전학회지
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• 제14권3호
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• pp.35-40
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• 2022

In this study, the driving performances of elderly who's age is over 65 were evaluated. The driving simulation was conducted using a compact driving simulation (CDS) and the simulation scenarios were developed from actual roads by replicating geometry of skewed intersection and traffic control devices located in Jungnang-gu, Seoul, Korea. 27 elderly drivers and 10 non-elderly drivers were recruited and participated on the virtual turning right and going straight driving experiment of CDS. Virtual driving data of driving time, speed, distance, acceleration and deceleration speeds, brake power, and steering wheel rotation angle were recorded and analyzed. Generally, elderly driver took more times to pass through the skewed intersection road and showed lower approaching speed as much as 40% and 25% in case of turning right and going straight scenarios respectively. The speed deviation at skewed intersection road between elderly and non-elderly driver is expected to cause frequent lane changes and overtaking.

• 한국융합학회논문지
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• 제9권5호
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• pp.7-14
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• 2018

자율주행택시, 자율주행셔틀과 같은 새로운 교통서비스들에 대한 연구들이 전 세계적으로 여러 도시들을 대상으로 진행 중이지만 대부분 현재 통행 수요는 출발시간이 고정적이라고 가정하고 기존 교통수단과 새로운 교통수단의 도입 효과를 분석한다. 본 연구는 자율주행기반 교통서비스 운영에서 통근자의 출발시간 조정에 따른 교통체계의 영향을 행위자기반 모형으로 분석하였다. 통행시간 선택에 대해 다양한 시나리오를 설정하였고 자율차를 수용할 수 있는 도로용량의 영향도 분석하였다. 분석결과 통근자가 원하는 출발시간에서 집에서의 활동종료시간과 출발시간이 상당히 조정된 후 시스템적으로 안정적인 통근통행이 완료되었으며, 또한 도로용량의 감소는 과도한 스케줄 조정에도 불구하고, 많은 통행자들이 9시 이전에 통근하기 어려운 것으로 나타났다. 이와 같은 결과를 통해 현재와 다른 교통운영과 교통가격정책이 필요성을 정책적 제언으로 제시하였다.

• 한국ITS학회 논문지
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• 제10권6호
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• pp.24-31
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• 2011

본 연구는 회전교차로의 운영효과를 다루고 있다. 회전교차로는 신호교차로에 비해 지체감소와 친환경적이라는 기존 연구결과에 따라 우리나라에서 설치가 고려되는 실정이다. 본 연구의 목적은 보행교통량을 고려한 회전교차로의 운영효과를 분석하는데 있다. 이를 위해 이 연구는 교차로 네트워크를 구성하고 보행교통량과 진입교통량에 따른 분석시나리오를 설정하고, 차량당 평균제어지체 비교 분석에 중점을 두고 있다. 이 연구에서는 VISSIM 프로그램이 교통 시뮬레이션 도구로 사용된다. 분석된 주요결과는 다음과 같다. 첫째, 보행교통량에 근거하여 지체를 분석한 결과, 보행교통량이 회전교차로의 운영에 큰 영향을 미치는 것으로 분석되었다. 둘째, 보행교통량이 증가할수록 회전교차로의 지체도 증가하여, 보행교통량 1,000인/시 일 때 1차로 회전교차로에서는 총 진입교통량 800pcph, 2차로 회전교차로에서는 1,600pcph 이상 진입 시 신호교차로가 회전교차로보다 운영효율이 높게 평가되었다.

• 한국소음진동공학회논문집
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• 제25권4호
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• pp.284-290
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• 2015

Road traffic noise is closely related with urban forms and urban components, such as population, building, traffic and land-use, etc. Hence, it is possible to minimize the noise exposure problem depending on how to plan new town or urban planning alteration. This paper provides ways to apply for urban planning in consideration of noise exposure through road traffic noise estimation for alteration of small-scale urban form. Spatial autoregressive model from the former study is used as statistical model for noise simulation. The simulation results by the spatial statistical model are compared with those by the engineering program-based modeling for 5 scenarios of small-scale urban form alteration. The error from the limitation of containing informations inside the grid cell and the difficulties of reflecting acoustic phenomena exists. Nevertheless, in the stage of preliminary design, the use of the statistical models that have been estimated well could be useful in time and economically.

• 한국도로학회논문집
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• 제18권1호
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• pp.109-117
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• 2016

PURPOSES : The goal of this study is to analyze the operational effects of special roundabouts at large-scale rotaries in Korea. In pursuing the above, this study gives particular attention to comparing standard roundabouts with special roundabouts. METHODS : This study reviews the various types of roundabouts, creates 270 scenarios, builds networks, and comparatively analyzes the operational effects by using VISSIM simulation model and SSAM(Surrogate Safety Assessment Model). RESULTS : First, the operational effects of standard and signalized roundabouts were analyzed, and it was determined that standard roundabouts are the best in the case of under-saturated traffic volume, and signalized roundabouts are the best in the case of over-saturated traffic volume. Second, the operational benefits of a Turbo roundabout were evaluated to be generally lower than the benefits of a standard roundabout, and the benefits of a Turbo roundabout increase when right-turn traffic volume increases. Finally, the safety conflicts of a Turbo roundabout were determined to be the least and decrease when right-turn traffic volume increases. CONCLUSIONS : This study suggests that Turbo roundabouts rank highest for safety, and signalized roundabouts are best for over-saturated traffic volume. This study can be expected to provide some implications for policy decision-making.

• 자동차안전학회지
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• 제15권3호
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• pp.53-58
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• 2023

Defects in the vehicle itself were considered the biggest risk factor for traffic accidents as the electrical and electronic components of vehicles, which were not there before, increase. Therefore, the vehicles have been developed based on ISO 26262 (an international functional safety standard) which is focusing on functional defect safety evaluation of electrical and electronic component systems. However, in the future, as autonomous driving technology is applied, even vehicles without functional defects must be prepared for the dangerous traffic situation that may arise from exceptional or external factors. SOTIF (Safety Of The Intended Functionality) is a concept to prevent exceptional or external factors. The main objective of SOTIF is to decrease Unknown & Unsafe factors as much as possible by finding Known factors and Unsafe factors. In this study, Prescan provided SIEMENS, one of the autonomous driving simulators, is used to make scenarios of IGLAD traffic accident cases. From the simulation results, Unsafe & Safe cases were classified and analyzed to derive unsafe factors.

• 한국도로학회논문집
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• 제17권1호
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• pp.91-98
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• 2015

PURPOSES : Although signalized intersections have been considered the best way to control traffic volume in urban areas for several decades, roundabouts are currently being discussed as an alternative way to control traffic volume, especially when traffic is light. Because a roundabout's efficiency depends on the load geometry as well as the traffic volume, design guidelines for roundabouts are recommended only if the incoming traffic volume is very low. It is rare to substitute a roundabout for an existing signalized intersection in urban areas. This study aims to estimate the benefits from the transformation of an existing signalized intersection into a roundabout in an urban area. When there is a more moderate volume of traffic, roundabouts can be effectively used by optimizing signals located at an approaching roadway. METHODS : The methodologies of this paper are as follows: First, a signalized intersection was analyzed to determine the traffic characteristics. Second, the signalized intersection was transformed into a roundabout using VISSIM microscopic traffic simulation. Then, we estimated and analyzed the effects and the performance of the roundabout. In addition, we adjusted a method to improve the benefits of the transformation via the optimization of signals located at an approaching road to control the incoming traffic volume. RESULTS : The results of this research are as follows: The signal-optimized roundabout improved delays compared with the signalized intersection during the morning peak hour, non-peak hour, and evening peak hour by 1.78%, 12.45%, and 12.72%, respectively. CONCLUSIONS : According to the simulation results of each scenarios, the signal-optimized roundabout had less delay time than the signalized intersection. If optimized signal control algorithms are installed in roundabouts in the future, this will lead to more efficient traffic management.