• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.55-63
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• 2020

Road traffic noise is a major complaint. Porous pavement (PP) has been proposed as an effective method for reducing road traffic noise, but it has not been applied much due to the lack of quantitative evaluation. In this study, the noise reduction of single-layer porous pavement (SLPP) and double-layer porous pavement (DLPP) was evaluated. The noise was measured using the CPX method, and the driving speed was measured every 10km/h from 50km/h to 80km/h. The differences in noise level between the two PPs were statistically significant. The driving speed had no significant effect on the difference in noise between the two PPs. The DLPP showed a 6.6dB(A) reduction in average and a 6.3dB(A) reduction at the 95% confidence level compared to the SLPP. Reducing noise by 5dB(A) is equivalent to reducing traffic to 1/3 or lowering the vehicle's speed to 1/2. Sensitively, it is possible to recognize a 3dB(A) and 5dB(A) difference. The DLPP and SLPP were very effective in reducing traffic noise.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.6
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• pp.108-117
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• 2011

Seoul metropolitan government has been operating traffic signal control system with the name of COSMOS since 2001. COSMOS uses the degrees of saturation and congestion which are calculated by installing loop detectors. At present, inductive loop detector is generally used for detecting vehicles but it is inconvenient and costly for maintenance since it is buried on the road. In addition, the estimated queue length might be influenced in case of error occurred in measuring speed, because it only uses the speed of vehicles passing by the detector. A traffic signal control algorithm which enables smooth traffic flow at intersection is proposed. The proposed algorithm assigns vehicles to the group of each lane and calculates traffic volume and congestion degree using traffic information of each group using VANETs(Vehicular Ad-hoc Networks) inter-vehicle communication. It does not demand additional devices installation such as cameras, sensors or image processing units. In this paper, the algorithm we suggest is verified for AJWT(Average Junction Waiting Time) and TQL(Total Queue Length) under single intersection model based on GLD(Green Light District) Simulator. And the result is better than Random control method and Best first control method. In case real-time control method with VANETs is generalized, this research that suggests the technology of traffic control in signalized intersections using wireless communication will be highly useful.

• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.95-106
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• 2005

Road accidents are considered as the result of a complex interplay between road, vehicle, environments, and human factors. Little study, however, has been carried out on the attributes of human factor compared to the road geometric conditions and traffic conditions. The previous researches focused on mainly both traffic and geometric conditions on specific location. Therefore, it's hard to explain phenomenon of the high traffic accident rates where road and traffic conditions are good. Because of these reasons, accident analysis has contributed on geometric improvement and has not contributed on traffic management such as selection of attention section, driver napping alert, etc. The freeway incident management is also associated with reliable prediction of incident occurrences on freeway sections. This paper presents a method for estimating the effect of trip length on freeway accident rate. A PAR (Potential Accident Ratio), the new concept of accident analysis, considering TLFDs (Trip Length Frequency Distributions) is suggested in this paper. This approach can help to strengthen freeway management and to reduce the likelihood of accidents.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.409-415
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• 2022

The length of the acceleration lane in the area of entrance terminals is calculated based on 13 PS/ton horsepower of a cargo truck in Korea, so it is generally overestimated compared with the capacity of most vehicles traveling on an entrance ramp. Most drivers have, therefore, an indiscreet tendency to enter the main lane in all sections of an acceleration lane, which affects the traffic flow of the main lane. Because of this tendency, measures are required to minimize the impact on traffic flow of the main lane. The operating speed, rate of entrance, and traffic volume for each vehicle were investigated at the entrance terminals of the interchanges (ICs) of Yangji IC, Suseok IC, Yongin IC, and Osan IC, and the level of improvement in traffic flow was analyzed via VISSIM simulation. From the VISSIM simulation analysis, 74.0 % of the total vehicles traveled over the specified speed from the nose point where drivers would be able to recognize the traffic condition of the main carriageway, or the point at which there is a simplification of the curve section. In addition, 88.6 % of the vehicles entered the main carriageway up to 0.8 points compared with the entire length of the acceleration lane. It was subsequently found that an improvement of average speed in the main carriageway and at the entrance ramp can be achieved from 60.1 km/h to 68.5 km/h by intentionally limiting the entrance point onto the main carriageway up to 0.265 points of the entrance ramp.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.6
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• pp.779-793
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• 2019

The ventilation rate (Qreq) requirement in road tunnels is not just a basic information for determining the tunnel cross-sectional area, but also a major factor for the ventilation system selection. The Qreq is predominantly dependent on the vehicle traffic volume, while among others, the vehicle exhaust emissions and permissible standards are critical. This paper analyzes the changes in the Qreq designing criteria and/or recommendations suggested by World Road Association and local authorities over the last 20 years, since the first local designing criteria was established in 1997 by Korea Expressway Corporation. Additionally, based on the updated vehicle emission standards of Ministry of Environment and recent recommendations of the World Road Association (WRA), changes in the Qreq and its effects are studied in terms of the length and grade of the tunnel.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.113-124
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• 2009

This paper suggests a new approach for providing information for driver safety at signalized intersections. Particularly dangerous situations at signalized intersections such as red-light violations, accelerating through yellow intervals, red-light running, and stopping abruptly due to the dilemma zone problem are considered in this study. This paper presents the development of a dangerous vehicle determination algorithm by collecting real-time vehicle speeds and times from multiple point detectors when the vehicles are traveling during phase-change. For an evaluation of this algorithm, VISSIM is used to perform a real-time multiple detection situation by changing the input data such as various inflow-volume, design speed change, driver perception, and response time. As a result the correct-classification rate is approximately 98.5% and the prediction rate of the algorithm is approximately 88.5%. This paper shows the sensitivity results by changing the input data. This result showed that the new approach can be used to improve safety for signalized intersections.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5321-5329
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• 2011

Space Layout has been an issue in the facet of reducing the co2 in that the transportation sector has been to represent almost more than 20% of the total energy consumption for decades. Beside the development of the more efficient transportation systems, an efficient space layout makes it possible to reduce the amount of energy consumption in the transportation sector through allocating the sub-spaces in such an arrangement of minimizing the travel distances. In line with this thinking, this research aims at implementing a simulator which can calculate the vehicle-based travel distance upon a certain space layout. Based on the findings that the vehicle-based travels take place between the two functionally related sub-spaces, this research addresses a method of calculating the vehicle-based travel distance by multiplying the traffic volume of each sub-spaces by the travel distance to the other connected sub-spaces.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.6
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• pp.251-258
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• 2018

Recently, due to the increase in the traffic volume of vehicle, the collision of the vehicle collision has been increased so that the neck injuries of the passengers has been increased. In order to prevent this, vehicle collision analysis research using computer simulation has been actively carried out in consideration of the design point of car seat. In this study, I used the MADYMO program for analyzing the passenger behavior using a BioRID II dummy, and predicted the neck injuries of passengers according to the change of the backset at the rearward collision of the driving speed of 16km/h. As a result, it was found that the shorter the backset, the shorter the contact start time but the contact completion time was almost the same and the T1 acceleration showed that the acceleration increased with the backset. In addition, the tensile strength increases as the backset increases, and NIC (Neck Injury Criterion) increases as the head speed reaches the headrest.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.4
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• pp.78-95
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• 2022

The result of previous studies and epidemiological invstigations for infectious diseases epidemic in livestock have shown that trips made by livestock-related vehicles are the main cause of the spread of these epidemics. In this study, the OD traffic volume of livestock freight vehicle during the week in each zone was calculated using livestock facility visit history data and digital tachograph data. Based on this, a model for predicting the spread of infectious diseases in livestock was developed. This model was trained using zonal records of foot-and-mouth disease in Gyeonggi-do for one week in January and February 2015 and in positive, it was succesful in predicting the outcome in all out of a total 13 actual infected samples for test.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.1
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• pp.35-42
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• 2010

The rapid economic development induced the massive road constructions, becoming bigger and high-speed of the vehicles. However, it brings lots of social problems, such as air pollutions, traffic noise and vibration. Special concrete block for the base course of asphalt pavement is needed to decrease traffic noise such as tire's explosive and vehicles sound, applying Helmholtz Resonators theory to asphalt pavement. If it is applied to the area where it happens considerable noise such as a junction, the street of a housing complex and a residential street, it is one of considerable method to solve the social requirements of noise problem. This research examines couple of laboratory tests for the sound absorption effect of the concrete block and the base concrete block. There are specimens which is fixed hall-size, space, depth as the condition of this research, and these are analysed of noise decrease effect using different condition of the first noise of each vehicle. As a result of analysis data according to vehicle noise volume, measurement distance, a form and size of the hall using the base concrete block, the use of special concrete base showed a good alternative solution for decreasing traffic noise level, from 4 dB to 9 dB.