• 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.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.2
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• pp.98-105
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• 2007

In this paper, we propose the method and system which determines the condition for safe and unsafe lane changing. To determine the condition, first, the system sets up the Region of Interest(ROI) on the neighboring lane. Second, a dangerous vehicle is extracted during the line changing. Third, the condition is determined to wm or not by calculating the moving direction, relative distance md relative velocity. To set up the ROI, the only one side lane is detected and the interested region is expanded. Using the coordinate transformation method, the accuracy of the ROI raised. To correctly extract the vehicle on the neighboring lane, the Adaptive Background Update method and Image Segmentation method which uses the feature of the travelling road are used. The object which is extracted by the dangerous vehicle is calculated the relative distance, the relative velocity and the moving average. And then in order to ring, the direction of the vehicle and the condition for safe and unsafe is determined. As minimizes the interested region and uses the feature of the travelling road, the computational quantity is reduced and the accuracy is raised and a stable result on a travelling road images which demands a high speed calculation is showed.

• Journal of Korean Society of Transportation
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• v.31 no.4
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• pp.32-46
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• 2013

Because of short length between interchanges, traffic congestion has been caused by a lot of short trip traffic in the urban section of interregional expressway. Also, in case of expressway with Bus Only Lane, bus causes dangerous situation by conflicting between vehicles and buses in order to access from Bus Only Lane to IC. Therefore, this study aims to propose Express Lane applied by Bus Only Lane as a new lane operation in order to efficiently operate and to analyze the effectiveness on constructing Express Lane to the Pangyo-Hannam section in Gyeongbu Expressway. The study analyzes effectiveness by scenario using the micro traffic simulation tool, VISSIM 5.4. For this, the indicators which evaluate construction effect of Express Lane, are used by average delay time, average speed and total travel time. The results of the study showed the best effectiveness when Express Lane installed one, and it represented an ideal traffic condition when long distance trip traffic of the whole traffic is 25% in the study section. Therefore, the construction of Express Lane using Bus Only Lane achieves positive effectiveness on safety and expense aspect as well as uncongested flow.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.81-86
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• 2013

This paper presents the lane change system for collision avoidance. The proposed algorithm for the collision avoidance consists of path generation and path following. Using a calculated TTC (Time to Collision), partial braking is operated and collision avoidance path is generated considering relative distance, velocity and acceleration. Based on the collision avoidance path, desired yaw angle and yaw rate are calculated for the automated path following. The lateral controller is designed by a Lyapunov function approach using 3 D.O.F vehicle model and vehicle parameters. The required steering angle is determined from wheel velocity, longitudinal and lateral velocity in order to follow the desired yaw angle and yaw rate. This system is developed MATLAB/Simulink and its performance is evaluated using the commercial software CarSim.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.245-253
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• 2002

A driver model with nervous neuromuscular system was developed to steer a vehicle along the prescribed path during handling simulations. A 3-dimensional vehicle model with 10 DOF and 3 DOF steering handle are used to perform a computer simulation. PID and fuzzy controller are used to perform single and double lane change, and their tracking abilities were compared. The effects of time delay and preview distance are also investigated, and it is demonstrated that the driver model developed can be an aid far objective evaluation of vehicle handling simulation.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.3
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• pp.31-38
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• 2022

The purpose of this study is to rediscover the gestalt psychological value of the Landscaping structure and architectural landscape in the vulnerable village consulted by experts in 2021 year. For this study, nine villages called of Saethul Maul were surveyed, and two of them were analyzed for landscape composing of gestalt psychology. The two villages, Yulwon and Jeonchon, included the case where the landscaping structure of residence was viewed from outside the village and the case from within the village. Psychological distance of the villages is analyzed by D/H ratio for the scenery seen from lanes. There are three expected conclusions. First, in terms of gestalt psychology, the buildings mean a figure, and the rice field in front of the village, the mountains behind the village, and the lanes represent a landscape structure consisting a background(ground). It captures the unique landscape aesthetics of the vulnerable village. Second, the landscape seen in the village shows various differences in horizontal distance and vertical height of the lane, so even if the psychological distance gives a sense of closure, it gives a sense of rhythm and change. However, considering the psychological distance (D/H ratio) when the roads are expanded for the fire car, the village landscape can be re-formed by safety and function. Third, the architectural landscape of Yulwon village is characterized by the harmonious arrangement of traditional houses, Narack-Doiji (rice barn), and wooden building (agricultural barn) in the background of chestnut tree hill behind the village. It is necessary to reduce the use of industrial materials and restore the valuable architectural landscape of the vulnerable village.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1D
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• pp.25-32
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• 2009

Currently, various types of TDM (Transportation Demand Management) policies are being studied and implemented in an attempt to overcome the limitations of supply oriented policies. In this context, this paper addressed issues of effectiveness and possible domestic implementation of the HOT lane. The possible site of implementation selected for this simulation study is part of the Kyung-bu freeway, where a dedicated bus lane is currently being operated. Minimum length of distance required in between interchanges and access points of the HOT lane for vehicles to safely enter and exit the lane, and traffic management policies for effectively managing the weaving traffic trying to enter and exit the HOT lane were presented. A 5.2km section of freeway from Ki-heuing IC to Suwon IC and a 8.3km section from Hak-uei JC to Pan-gyo JC have been selected as possible sites of implementation for the HOT lane, in which congestion occurs regularly due to the high level of travel demand. VISSIM simulation program has been used to analyze the effects of the HOT lane under the assumption that one-lane HOT lane has been put into operation in these sections and that the lane change rate were in between 5% to 30%. The results of each possible scenario have proven that overall travel speed on the general lanes have increased as well by 1.57~2.62km/h after the implementation of the HOT lane. It is meaningful that this study could serve as a basic reference data for possible follow-up studies on the HOT lane as one effective method of TDM policies. Considering that the bus travel rate would continue increase and assuming the improvement in travel speed on general lanes, similar case study can be implemented where gaps between buses on bus lane are available, as a possible alternative of efficient bus lane management policies.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.136-145
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• 2004

In companion paper, the composition and structure of the traffic environment is derived. Rules to regulate agent behaviors and the frameworks to communicate between the agents are proposed. In this paper, the model of a driver agent which controls a vehicle agent is constructed. The driver agent is capable of having different driving styles. That is, each driver agent has individual behavior settings of the yielding index and the passing index. The yielding index can be defined as how often the agent yields in case of lane changes, and the passing index can be defined as how often the agent passes ahead. According to these indices, the agents overtake or make their lanes for other vehicles. Similarly, the vehicle agents can have various vehicle dynamic models. According to their dynamic characteristics, the vehicle agent shows its own behavior. The vehicle model of the vehicle agent contains the nonlinear subcomponents of engine, torque converter, automatic transmission, and wheels. The simulation has proceeded for an interrupted flow model. The result has shown that it is possible to express the characteristics of each vehicle and its driver in a traffic flow, and that the change of the traffic state is closely related with the distance and the signal delay between intersections. The system developed in this paper shows the effectiveness and the practical usefulness of the traffic simulation.

• Journal of Korean Society of Transportation
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• v.20 no.6
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• pp.115-128
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• 2002

Traffic engineers have developed and implemented various microscopic simulation models to verify the traffic performance and to prevent the expected problems. The existing microscopic simulation models categorize drivers into several types to reflect various drivers' driving patterns but miss the dynamics of drivers' behavior changed based upon the traffic conditions. It was found from the field data collected from two different merging sections on an urban freeway in Seoul, Korea, that the drivers' critical gap distributions are changed based on (1) the traffic density on the adjacent lane to the acceleration lane and (2) the opportunities left to merge in terms of distance to the end of acceleration lane. It was also found from the study that the drivers' critical gap distributions follow the Normal distribution. and its mean and variance change while a vehicle progresses on an acceleration lane. This paper proposes a new gap-acceptance model developed based on a set of drivers' critical gap distributions from each segment on the acceleration lanes. Through the comparison study between the field data and the results from the simulation utilizing the proposed model, it was verified that (1) the distribution of merging points on an acceleration lane to the adjacent main lane at different density levels, (2) the size of the gap accepted for merging and (3) the speed difference between the merging vehicle and the trailing vehicle at the time of merging are statistically identical to the field data at 95% confidence level.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.879-885
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• 2018

The highway weaving section is a point where there is a conflict caused by entry and exit vehicles. In order to minimize the impact on the main line, an accumulation line should be installed. The design speed of the collecting part is 50 km/h, but the actual driver does not have proper deceleration according to the design speed. In this study, considering the driving behaviors, the design specification, and the driver 's viewing angle, the appropriate separation distance for safe entry and exit of collecting, connecting, and collecting roads was examined. As a result of the analysis, it is found that a distance of 60m is required from the point where the merging starts. The results of this study are expected to contribute to the improvement of driver safety due to the conflict between entry and exit vehicles when applied to the weaving section where collecting roads are installed.