• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.5
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• pp.834-840
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• 2001

A real time multibody vehicle dynamics model has been developed and implemented using a subsystem synthesis method based on recursive formulation. To verify real time simulation capability the developed model has been applied to HMMWV(High Mobility Multipurpose Wheeled Vehicle) with steering system. For the kinematically driven steering system, the coupled front suspension-steering subsystem can be decoupled into two SLA suspension subsystems, which improves the efficiency of simulation. To investigate theoretical efficiency, operational counting method has been also employed to compare the proposed model with the conventional recursive dynamics model. Various simulations such as unsymmetric bump run, step steering(J-turn) and sine steering input test have been carried out to verify the real time feasibility of the proposed model.

• International Journal of Automotive Technology
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• v.7 no.7
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• pp.777-784
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• 2006

The lateral dynamic behaviours of a track inspection vehicle with laterally guided system are studied for the safety and comfort. A 10-DOF dynamic model is proposed counting for lateral and yaw motions. The equations for motions of the vehicle running on curved tracks at a constant speed are presented. It is shown by simulation that lateral guiding forces applied to the guiding wheels on the inner side of the track increase in a larger scale in comparison with those on the outer side when the vehicle passes through curved tracks with cant, and the front guiding spring forces is larger than the rears. Lateral vibrations due to yaw motions of the vehicle take place when the vehicle runs through curved tracks. Finally, effect of the lateral guidance on the vehicle dynamics is also examined and advantages of such a guiding system are discussed in some details. An optimal guided control is applied to restrain the lateral and yaw motions. The comparisons between the active and passive guidance explain the effect of the active control approaches.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2615-2625
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• 2011

Recently in worldwide and Korea domestically, the LRT vehicles are introduced as reputable urban transit system, in a view of energy saving, punctuality and eco-friendly as well as transport efficiency. At first time in Korea, the Busan metro Line 4 was applied with AGT system which is a kind of LRT using the Rubber tired AGT vehicle and developed from 1999 to 2004 in charge of Korean government. Busan selected the AGT system for Metro Line 4 as the solution of traffic jam and networking the intercity. At present, Busan Metro Line 4 has been running since opened at March 30, 2011. The vehicle of Busan metro line 4 is aiming the maximization of LRT vehicle advantage that is the lightness of vehicle size and vehicle weight. So, it did size downed and weight downed by lightened the weight of car frame and bogies and by the compactness of electrical on-board equipments. The study carried out the structure analysis to verify and safety and performance of car body and bogie frame of Busan Metro Line 4 vehicles. In this study, it was analyzed the stress of main load and verified the fatigue strength. And measured the dynamic stress sending to body structure and bogie frame while running on main line and analyzed the fatigue stress. As a result, it verified the safety and life cycle of car body and bogie frame.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.11
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• pp.610-620
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• 2003

Various shadows are one of main factors that cause errors in vision based vehicle detection. In this paper, two simple methods, land mark based method and BS & Edge method, are proposed for vehicle detection and shadow rejection. In the experiments, the accuracy of vehicle detection is higher than 96%, during which the shadows arisen from roadside buildings grew considerably. Based on these two methods, vehicle counting, tracking, classification, and speed estimation are achieved so that real-time traffic parameters concerning traffic flow can be extracted to describe the load of each lane.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.5
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• pp.42-51
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• 2001

Vehicle detection is the basic of traffic monitoring. Video based systems have several apparent advantages compared with other kinds of systems. However, In video based systems, shadows make troubles for vehicle detection, especially active shadows resulted from moving vehicles. In this paper, a new method that combines background subtraction and edge detection is proposed for vehicle detection and shadow rejection. The method is effective and the correct rate of vehicle detection is higher than 98% in experiments, during which the passive shadows resulted from roadside buildings grew considerably. Based on the proposed vehicle detection method, vehicle tracking, counting, classification and speed estimation are achieved so that traffic parameters concerning traffic flow is obtained to describe the load of each lane.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.161-170
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• 2001

Vehicle detection is the basic of traffic monitoring. Video based systems have several apparent advantages compared with other kinds of systems. However, In video based systems, shadows make troubles for vehicle detection. especially active shadows resulted from moving vehicles. In this paper a new method that combines background subtraction and edge detection is proposed for vehicle detection and shadow rejection. The method is effective and the correct rate of vehicle detection is higher than 98(%) in experiments, during which the passive shadows resulted from roadside buildings grew considerably. Based on the proposed vehicle detection method, vehicle tracking, counting, classification and speed estimation are achieved so that traffic information concerning traffic flow is obtained to describe the load of each lane.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.672-675
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• 2012

SMART Highway 사업은 첨단 IT통신과 자동차 및 도로 기술이 접목된 세계 최고수준의 빠르고 편안한 지능형 녹색도로 실현을 목표로 하고 있다. SMART Highway의 도로-자동차 기반 교통운영에서 핵심기술인 VANET(Vehicular Ad-hoc Network)은 다수의 차량들이 무선통신을 이용하여 차량 간 통신 또는 차량과 RSU(Road Side Unit)사이의 통신을 제공하는 차세대 네트워킹 기술이다. 특히, 운전자의 안전에 직접적인 영향을 끼칠 수 있는 V2V 통신의 경우 차량 간의 안전한 통신을 위해 차량 간 상호인증이 반드시 고려되어야 한다. 이처럼 빠른 속도로 이동하는 차량 간 인증이 원활이 이루어지기 위해서는 기존의 네트워크에서 사용된 인증방식은 그대로 적용시키기 어렵다. 따라서 본 논문에서는 다수의 차량 간 통신 시에 보다 효율적인 차량 인증을 위해 카운팅 블룸필터를 이용한 차량 인증 기법을 제안한다.

• Korean Management Science Review
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• v.13 no.2
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• pp.1-11
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• 1996

Two different methods to extract the license plate area of a vehicle have been used for automatic recognition purposes. One method is with a color vision system and the other is with an edge detecting operator. The system with color vision has some problems if the colors of license plate and vehicle's body are similar. The various plate colors in Korea also drops the system performance. The edge detecting operator also has a problem for a real time processing since it performs on all pixels of the scene. In this paper a possible method using gray level vision system and available pre-known information of license plates is suggested. The suggested procedure searches the lower boundary of the plate by counting high contrast points between one and near pixel from the bottom line of the scene. It finds the upper boundary from the bottom line by adding number plate height after finding the lower boundary. The left and right boundaries are found by similar processes.

• Journal of Korean Society of Transportation
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• v.21 no.1
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• pp.53-63
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• 2003

The Origin-Destination(OD) matrix is very important in describing transport movements in a region. The OD matrix can be estimated using traffic counts on links in the transport network and other available information. This information on the travel is often contained in a target OD matrix and traffic counts in links. To estimate an OD matrix from traffic counts, they are the major input data which obviously affects the accuracy of the OD matrix estimated, Generally, the quality of an estimated OD matrix depends much on the reliability of the input data, and the number and locations of traffic counting points in the network. Any Process regarding the traffic counts such as the amount and their location has to be carefully studied. The objective of this study is to select of the optimal location of traffic counting points for the OD matrix estimation. The model was tested in nationwide network. The network consists of 224 zones, 3,125 nodes and 6,725 links except to inner city road links. The OD matrix applied for selection of traffic counting points was estimated to 3-constrained entropy maximizing model. The results of this study follow that : the selected alternative to the best optimal counting points of six alternatives is the alternative using common links of OD matrix and vehicle-km and traffic density(13.0% of 6,725 links), however the worst alternative is alternative of all available traffic counting points(44.9% of 6,725 links) in the network. Finally, it should be concluded that the accuracy of reproduced OD matrix using traffic counts related much to the number of traffic counting points and locations.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.68-73
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• 2000

This study to embody automatic recognition of VIN(Vehicle Identification Number)character by computer vision system. Automatic recognition characters methods consist of the thining processing and the recognition of each character. VIN character and background classified using counting method of the size of connected pixels. Thining processing applied to segmentation of connected fundamental phonemes by Hilditch's algorithm. Each VIN character contours tracing algorithm used the Freeman's direction tracing algorithm.