• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.5
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• pp.23-35
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• 2011

The pedestrian green time is usually long at wide width intersections. This sometimes causes the increase of delay on the whole intersection because of long cycle length and thus small g/C ratio on some direction. In this paper, to improve these problems, staggered pedestrian crossing was evaluated on the vehicular and pedestrian aspects. The results were gained by using both TRANSYT-7F and VISSIM model. The vehicle control delay of the staggered pedestrian crossing was estimated to be decreasing than that of the general pedestrian crossing by 14.9% to 85.6%. The pedestrian average delay of two pedestrian crossing systems was examined by analytical method and VISSIM. According to the analytical method there was no significant difference between each pedestrian crossing system. The pedestrian delay of staggered pedestrian crossing was from 13.4% to 22.3% than the general pedestrian crossing by VISSIM. In conclusion, the staggered pedestrian crossing was more effective than general pedestrian crossing for both the vehicle and the pedestrian. However this conclusion was resulted from micro simulation where traffic volume condition, v/c, was from 0.8 to 1.1.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.6
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• pp.15-22
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• 2012

A performance index of singalized intersections is a standard to optimize signal control variables and to manage traffic flow. Traffic delays is generally used to minimize the average delay time on intersections or networks, progression efficiency is used to improve travel speed of main cooridors or to provide transit signal priority. We manage traffic flows with only selecting one index between delays and progression according to the objective of traffic management and field characteristics. In real field, the driver's satisfaction is high in any performance criteria when the waiting time is shorter and the unnecessary stop in front of traffic is smaller. This paper aims to develop simulation model to represent real progression with concurrently considering delays and progression. In order to reflect an effect of level of traffic volumes and residual queues which don't be considered in prior progression model, we apply shockwave model with flow-density diagram. We derive Cell Transmission Model of Daganzo in order to develop the delay index and the progression index for the macroscopic simulation model. In order to validate the effect, we analysis traffic delays and progression efficiency with comparing this model to Transyt-7F and PASSER V.

• Journal of Korean Society of Transportation
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• v.17 no.2
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• pp.83-90
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• 1999

A computer algorithm is presented that evaluate the performance of coordinated signal timing plans for the signalized arterials. The procedures calculating delay and stops are based on Michalopoulos's analytical model derived from shock wave theory. The delay-offset relationship predicted from the algorithm produced consistent results with the delays venerated by TRANSYT-7F. From performance test, the delays estimated using the proposed a1gorithm are shown to be sensitive to the quality of progression as well as to traffic demand, link length, and turning flow ratio from upstream signal.

• Proceedings of the KOR-KST Conference
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• 1998.10a
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• pp.245-251
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• 1998

좌회전 제어네는 크게 좌회전을 금지하는 적극적인 제어에서 좌회전 신호와 좌회전 차선의 디자인 및 차선 설정과 같은 비교적 소극적인 제어가 있다. 기존의 좌회전에 관한 많은 연구는 대부분 후자의 소극적인 제어를 통한 제어효과를 파악하는데 주로 관심을 두었다. 좌회전금지의 효과분석 방법론에는 크게 교차로 및 링크(Link)와 네트워크(Network)의 두가지 차원의 접근 방법이 있다. 교차로 및 링크(Link) 차원의 분석은 TRANSYT 7F, PASSER IV 등과 같은 가로망에서 신호시간을 최적화하는 모형과 NETSIM, COSIM과 같이 조건에 따라 실제 차량의 행태를 모사하는 시뮬레이션 모형 등에서 좌회전 신호현시를 주거나, 주지 않음으로써 전후의 변화를 관찰, 분석에 이용할 수 있다. 그러나, 이러한 접근방법은 개별교차로에서 현시운영에 따른 효과를 분석하기에는 용이할 지 모르나, 좌회전 금지에 따라 전환된 교통량을 합리적으로 처리하는데 문제를 가지고 있다. 이에 반해 네트워크(Network) 차원의 분석은 좌회전 금지에 따른 거시적 수요변화를 파악하여, 좌회전금지에 따라 전환된 교통량을 합리적으로 수용 할 수 있으며, 교차로 및 링크(Link) 차원의 분석기법과의 결합을 통해 개별교차로에서 현시운영에 따른 효과도 어느정도 예견할 수 있을 것으로 예상되지만, 이에 관련한 여구가 전무한 형편이다. 본 연구의 목적은 네트워크(Network) 차원에서 좌회전 금지에 따른 효과 분석 모형을 정립하고, 가상 네트워크에 적용 그 유효성을 검증하여, 지역 네트워크의 개별교차로에서 좌회전 금지의 도입에 대한 의사결정의 기준을 마련하는데 있으며, 이를 위한 구체적 연구 내용은 다름과 같다. 첫째, 순간 동작 사용자 최적 통행배정모형의 구조 및 특성 파악. 둘째, 기존 가로망 표현기법의 구조 및 특성파악. 셋째, 좌회전 금지에 따른 효과 분석을 위한 순간 동적 사용자 최적 통행배정모형의 구축. 넷째, 좌회전 금지에 따른 효과 분석을 위한 가로망 표현기법의 개발. 다섯째, 가상 네트워크에서 구축된 모형을 통한 교차로에서 좌회전 금지 효과분석

• International Journal of Highway Engineering
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• v.15 no.6
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• pp.125-133
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• 2013

PURPOSES : The purpose of this study is to propose delay-minimizing operation methodology of a signalized intersection based upon optimization of lane-uses on approaching lanes for an intersection. METHODS : For the optimization model of lane-uses, a set of constraints are set up to ensure feasibility and safety of the lane-uses, traffic flow, and signal settings. Minimization of demand to saturation flow ratio of a dual-ring signal control system is introduced to the objective function for delay minimization and effective signal operation. Using the optimized lane-uses, signal timings are optimized by delay-based model of TRANSYT-7F. RESULTS : It was found that the proposed objective function is great relation with delay time for an intersection. From the experimental results, the method was approved to be effective in reducing delay time. Especially, cases for two left-turn lanes reduced greater delays than those for a left turn lane. It is noticed that the cases for different traffic volume by approach reduced greater delays than those for the same traffic volume by approach. CONCLUSIONS : It was concluded that the objective function is proper for lane-uses optimizing model and the operation method is effective in reducing delay time for signalized intersections.

• International Journal of Highway Engineering
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• v.16 no.5
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• pp.109-119
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• 2014

PURPOSES : The control delay in seconds per vehicle is the most important traffic operational index to evaluate the level of service of signalized intersections. Thus, it is very critical to calculate accurate control delay because it is used as a basic quantitative evidence for decision makings regarding to investments on traffic facilities. The control delay consists of time-in-queue delay, acceleration delay, and deceleration delay so that it is technically difficult to directly measure it from fields. Thus, diverse analysis tools, including CORSIM, SYNCHRO, T7F, VISTRO, etc. have been utilized so far. However, each analysis tool may use a unique methodology in calculating control delays. Therefore, the estimated values of control delays may be different by the selection of an analysis tool, which has provided difficulties to traffic engineers in making solid judgments. METHODS : This study was initiated to verify the feasibility of diverse analysis tools, including HCM methodology, CORSIM, SYNCHRO, T7F, VISTRO, in calculating control delays by comparing estimated control delays with that measured from a field. RESULTS : As a result, the selected tools produced quite different values of control delay. In addition, the control delay value estimated using a calibrated CORSIM model was closest to that measured from the field. CONCLUSIONS : First, through the in-depth experiment, it was explicitly verified that the estimated values of control delay may depend on the selection of an analysis tool. Second, among the diverse tools, the value of control delay estimated using the calibrated microscopic traffic simulation model was most close to that measured from the field. Conclusively, analysts should take into account the variability of control delay values according to the selection of a tool in the case of signalized intersection analysis.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.1
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• pp.83-93
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• 2020

The time delay is used as a major indicator of the level of traffic congestion on traffic crossroads. For this purpose, the Daechi Station intersection where traffic congestion occurs and the Yeongdong 5 Bridge intersection where the traffic condition is relatively good, and the average lag time based on the field survey with the lag time calculated various simulation programs. comparison of the average control delay of the field survey data the signal intersection analysis model the KHCS Dechi intersection 7.7 second / vehicle Young dong 5 bridge intersection 7.9 second / vehiclehe VISSIM showed a difference Dechi intersection 21.1 second / vehicle and Young dong 5 bridge intersection 8.1 second / vehiclehe T7F showed a difference Dechi intersection 3.3 second / vehicle and Young dong 5 bridge intersection 9.3 second / vehicle. Analyzing the same intersection proved that the results differed from one simulation model to another.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.3
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• pp.9-15
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• 2011

The left-turn actuated signal control method has been occurred various problems under the COSMOS. one of problems is a early termination for left-turn phase by u-turn vehicles at left-turn lane. Therefore, the purpose of this study is a development of the efficient left-turn actuated signal control method to improve the problem. This study was considered that setback the left-turn vehicle detector to the start point of u-turn line and adjustment of the passage time. For effective analysis of developed method, Traffic simulation was simulated by T-7F and VISSIM under various traffic conditions. The result was proved that the developed Method improved the effectiveness.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.81-98
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• 2002

This paper documents the development of a bi-objective(minimizing delays and Queue lengths) cycle-free signal timing length model using Genetic Algorithm. The model was embodied using MATLAB. the language of technical computing. A special feature of this model is its ability to concurrently manage delays and queue lengths of turning movement concurrently. The model produces a cycle-free signal timing(cycles and green times) for each intersection on the cycle basis. Appropriate offsets could be also accomplished by applying cycle-free based signal timings for respective intersections. The model was applied to an example network which consists of four intersections. The result shows that the model produces superior signal timings to the existing signal timing model in terms of managing delays and queue lengths of turning movements.

• Journal of Korean Society of Transportation
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• v.14 no.4
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• pp.91-106
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• 1996

This paper deals with on the efficiency questions of the left-turn prohibit at an isolated intersection and a corridor with 5-phase signal system. Its objectives are three-fold ; (1) to analyze the efficiency of the left-turn prohibit with the use of an imaginary network, (2) to evaluate various factors under consideration in decision making on the left-turn prohibit, (3) to provide a framework for estimating and evaluating overall impacts of the left-turn prohibit in traffic network. the major findings using an imaginary network and computer packages such as MINUTP, TRANSYT-7F and STATGRAPH are followings. First, left-turn prohibit reduces cycle length by 33 seconds and delay time per vehicle by 36 seconds at an isolated intersection, and cycle length by 31 seconds and delay time per veicle by 43 seconds along a corridor. Second, total vehicle mile of travel and total travel time at an isolated intersection seem up to increase 38.85 miles(57.36km), 14.4 hour on the average, Regarding to a corridor, total vehicle mile of travel is increased by 50.14 miles(80.22km), but total travel time is decreased by129.9 hours. Third, the efficiency of left-turn prohibit are affected the following eight factors including left-turn volume(veh/hr) and ratio(%), average delay time per vehicle(sec/veh) and others. Finally, several simple and multiple regression models to evaluate the impacts on the left-turn prohibit are formulated from the above eight factors. It can be expected that these models will take an important role in decision-making of left-turn prohibit.