• ETRI Journal
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• v.20 no.2
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• pp.171-191
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• 1998

In this paper, we propose a new heuristic design algorithm for the virtual path (VP)-based ATM network with multiple traffic classes, in which QoS constraints associated with traffic class are taken into account. The minimum bandwidth of VP required to carry given amount of traffic is obtained by utilizing an equivalent bandwidth concept, and the route of each VP is placed so that the network cost is minimized while the QoS requirement is fulfilled To evaluate our design algorithm, we consider two kinds of traffic: voice traffic as low speed service and still picture traffic as high speed service. Through numerical examples, we demonstrate that our design method can achieve an efficient use of network resources, which results in providing a cost-effective VP-based ATM network.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.105-105
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• 2018

• Journal of Korean Society of Transportation
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• v.21 no.6
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• pp.57-65
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• 2003

Traffic congestion on the streets is the major concern of Metropolitan areas in Korea. Especially the signalized intersections are the main spots where traffic congestion is to be created. Currently the subway construction has been on the process in Taegu Metropolitan city. The subway stations are usually located at the intersections where a large number of vehicles and people are moving. During the constructional period, such an intersection creates profoundly a great deal of traffic congestion due to the open-cut constructional method. Under circumstance of the constructional method, the lane configurations should be changed frequently and the surface conditions make drivers uncomfortable. The propose of this study is to propose the improved method of traffic operation at the large circled intersection under the construction. The Signalized Modern Roundabout(SMR) is applied modifying from the modern roundabout. The geometric design and signal operation of SMR is developed in this study. To verify the operation of SMR the comparative study is conducted between the operation of the open-cut method and SMR method using the micro-simulation program, NETSIM. The result of simulation shows that the delay caused by the operation of SMR is not higher than that under the open-cut method. SMR makes also the constructional period shorten, makes the cost of construction lessened and makes drivers more comfortable as well than the method of open-cut. Therefore, the study concludes that the operation of SMR is more efficient, economic and safer method than that of open-cut method at the large circled intersection under construction.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.671-680
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• 2016

This research suggested a new real-time traffic signal control algorithm using fusion data of the travel time and the occupancy rate. This research applied the travel time data of traffic information system to traffic signal operation, and developed the signal control process using the degree of saturation that was estimated from the travel time data. This algorithm estimates a queue length from the travel time based on a deterministic delay model, and includes the process to change from the queue length to the degree of saturation. In addition, this model can calculate the traffic signal timings using fusion data of the travel time and the occupancy rate based on the saturation degree. The micro simulation analysis was conducted for effectiveness evaluation. We checked that the average delay decreased by up to 27 percent. In addition, we checked that this signal control algorithm could respond to a traffic condition of oversaturation and detector breakdown effectively and usefully. This research has important contribution to apply the traffic information system to traffic signal operation sectors.

• Journal of Navigation and Port Research
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• v.32 no.7
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• pp.521-527
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• 2008

The Istanbul Strait is one of the important waterways in the world. And its southern entrance has a highly congested local traffic. Till now there are several studies regarding how the Istanbul Strait is dangerous to navigate and how those dangers can be mitigated. But there is no study regarding local traffic which is posing great collision risk. In a certain traffic area, marine traffic safety assessment parameters are traffic volume, frequency of collision avoidance maneuver, traffic density, traffic flow and potential encounter, In this paper local traffic volume, traffic flow and potential encounter number of local traffic vessels and possibility of collision are investigated in order to find degree of danger at the southern entrance of the Istanbul Strait. Finally by utilizing those, risky areas are determined for southern entrance of the Istanbul Strait. Results have been compared to a previous study regarding risk analysis at congested areas of the Istanbul Strait (Aydogdu, 2006) and consistency of the results were presented.

• Journal of Korean Society of Transportation
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• v.25 no.3
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• pp.7-17
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• 2007

This study suggests ways to utilize the concept of environmental justice in order to improve the environment through strategies related to emissions. In Particular, this study explores ways to ameliorate the environment and traffic in consideration of environmental justice instead of simply aiming to reduce emissions. Real-time traffic information was gathered using ITS, it was input into a simulation model. and the level of present exhaust fume emissions was found. At the same time, based on current traffic situations, diverse strategies for reducing emissions were evaluated and appropriate executable alternative measures for ensuring environmental justice were provided.

• The Korean Journal of Emergency Medical Services
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• v.4 no.1
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• pp.63-71
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• 2000

Exceptive clause of ambulance stated in Road Traffic Laws of ambulance car accidents is not properly applied and emergency staffs who transfer over 85% of emergency cases are to be forced to start out to the emergency field with unstable conditions which they may be punished on the criminal and civil laws. Hereby this study makes the following suggestions to activate the duties of transferring emergency cases by emergency staffs, promote their morale and diminish the victim of emergency staffs due to traffic accidents. 1) It is prescribed that ambulance car drivers should be protected legally by applying the exceptive clauses thoroughly regulated in special case clauses because ambulance cars are used for the purpose of saving the human life. 2) On the traffic accidents occurred during the transfer of emergency cases, the special insurance system is created for treating the ambulance car accidents, not to bind the emergency staff's mistake to traffic law and the victims are compensated by the nation on the basis of insurance system and emergency staffs have the systematic security. 3) On the road over six lanes, emergency lane is set on the center and ambulance car should be used as the exclusive lane. 4) Ambulance car drivers must have the habit of transferring emergency cases rapidly within the range of legal operation.

• Journal of the Korean Professional Engineers Association
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• v.19 no.2
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• pp.21-25
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• 1986

Structure-borne noise due to forced vibration which is originated from subway operation and transmitted to buildings in order of rail-wood tie-concrete bed-structure-soil-building foundations-members of building results in social problem of environmental pollution. Moreover this becomes a serious problem because of the increment of surface traffic and subway operation made by meeting traffic system in crowded cities. Since subway is constructed along the principal road or through the residential area and as the worst case may be, building foundations is contact with top part of subway structure, it is possible that vibration resonance results in fatal damage of buildings. And, structure-borne vibration noise due to subway operation at late and early hours have the residents suffer from insonmia, restlessness and so on. Therefore, to satisfy the future need concerning the environmental protection, this report deals with the influence of structure-borne vibration noise on the basis of the characteristics of Seoul Subway System.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.675-682
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• 2006

The command of Subway is intended to adjust and control the train operation, and to play a key role of the total passenger transport and all kinds of affairs related to the safe train operation. Also, this can be considered as affairs to be controlled and operated by Total Traffic Control. For the purpose of developing the ATO system in using the new control technology by substituting the conventional ATS equipment, this technical document includes the technical points resulted from doing the replacement construction in the entire section of Subway Line 2 by Seoul Metro. The replacement work with the new ATO System should neither stop nor affect the system under operation while operating the current ATS System. The different systems should not interfere with each other while performing their individual affairs, and be composed to share the important data for the parallel operation. This technology is needed to proceed in assurance of a high degree of reliability.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.119-130
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• 2009

The aim of this study is to analyze the effects of DVR(Driving Video Recorder) operation on decreasing the number of traffic accidents, the cost of traffic accident claim, and the behavioral change in drivers' driving. The data for this research are obtained from taxi drivers in Busan. For this, Structural Equation Model and two-way ANOVA are employed for empirical analysis. Overall results of this study show that the number of traffic accidents of 4 taxi corporations in Busan has decreased by average 32.7 percent after using DVRs. In addition, as to the cost of taxi accident claims, it is expected that the DVR operation has a considerable effect on economic benefits of taxi corporations. Moreover, this study could make clear the difference in behaviors between DVR users and non-users, and discriminate the positive and negative impacts of the DVR operation on the drivers' driving behavior. The study quantitatively examined the indirect impact of 'attitude', 'subject norm' and 'behavioral control' factors on planned 'behavior', and the direct impact of 'behavioral control' factor on the planned 'behavior'. This study suggests that they should add the video recoding function of DVRs when operation recorder(blackbox for the car) is obligatorily set up on cars for business by traffic security law.