• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.6
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• pp.33-42
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• 2010

Travel speed is an important parameter in measurement of road traffic. UTIS(Urban Traffic Information System) was developed as a type of section detector. However, UTIS incur errors caused by irregular vehicle trajectories, wireless communication range and so on. This paper suggests a new model that use an error-filtering algorithm to improve the accuracy of travel speed measurements. In the field test, the variance of the percent errors measured by the new model was reduced. Therefore, it can be concluded that the proposed model significantly improves travel speed measuring accuracy.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.8 s.227
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• pp.1125-1134
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• 2004

This paper presents a mathematical model which is about the dynamics of not only a two wheel steering vehicle but a four wheel steering vehicle. A sliding mode ABS control strategy and PID rear wheel control logic are developed to improve the brake and cornering performances, and enhance the stability during emergency maneuvers. The performances of the controllers are evaluated under the various driving road conditions and driving situations. The numerical study shows that the proposed full car model is sufficient to accurately predict the vehicle response. The proposed ABS controller reduces the stopping distance and increases the vehicle stability. The results also prove that the ABS controller can be employed to a four wheel steering vehicle and improves its performance. The four wheel steering vehicle with PID rear wheel controller shows increase of stability when a vehicle speed is high and sharp cornering maneuver when a vehicle speed is low compared to that of a two wheel steer vehicle.

• The Journal of Korea Robotics Society
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• v.11 no.3
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• pp.115-126
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• 2016

This paper suggests the method of the spherical signature description of 3D point clouds taken from the laser range scanner on the ground vehicle. Based on the spherical signature description of each point, the extractor of significant environmental features is learned by the Deep Belief Nets for the urban structure classification. Arbitrary point among the 3D point cloud can represents its signature in its sky surface by using several neighborhood points. The unit spherical surface centered on that point can be considered to accumulate the evidence of each angular tessellation. According to a kind of point area such as wall, ground, tree, car, and so on, the results of spherical signature description look so different each other. These data can be applied into the Deep Belief Nets, which is one of the Deep Neural Networks, for learning the environmental feature extractor. With this learned feature extractor, 3D points can be classified due to its urban structures well. Experimental results prove that the proposed method based on the spherical signature description and the Deep Belief Nets is suitable for the mobile robots in terms of the classification accuracy.

• International Journal of Automotive Technology
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• v.7 no.1
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• pp.51-59
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• 2006

The high potential for injury involved in rollover accidents warrants the development of a system to protect passengers against such events. To effectively implement such a protection system, it is first necessary to determine rollover criteria (i.e., real time states which indicate the occurrence of rollover events). In this paper, several rollover criteria have been developed based on simplified physical models. Such accidents are first classified into two types, untripped and tripped, according to the main cause that initiates the rollover. Characteristics of these rollover situations are identified by applying appropriate principles of dynamics to corresponding simplified physical models. Two main rollover criteria, Rotational Kinetic Energy (RKE) and Initial Kinetic Energy (IKE), are then introduced based on these characteristics. ADAMS/View simulations have been performed to verify the feasibility of the introduced rollover criteria. ADAMS/Car simulations have also been conducted to get more realistic rollover data with a complete vehicle model. Results of these experiments reveal that our established criteria prove useful for predicting whether actual rollover occurs or not.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.3
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• pp.226-231
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• 2012

Autoparking assistant systems are a new and very promising area in automotive systems engineering. Since the traffic in modern cities becomes more intense, it is getting harder for a driver. Those systems are necessary for an inexperienced one to find a proper parking slot, or to park in a narrow parking slot without damaging his car or the vehicles around. The implementation of autoparking assistant systems may reduce drivers' stress and make parking generally more comfortable. In addition, such system can be extremely useful for senior or disabled people or for drivers with reduced mobility. The implementation of autoparking assistant systems may increase the safety of the parking, and therefore the development of such systems is a highly-demanded task. We introduce an intelligent autoparking system that automatically generates trajectory for parking using a fuzzy logic. This paper consists of three parts. In first part we introduce trajectory generation method for parallel parking without collisions. Fuzzy-logic based trajectory generation algorithm is described in second part. Experimental results presented in the third part of the paper prove effectiveness of the proposed method.

• Journal of the Korea Society of Computer and Information
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• v.11 no.4 s.42
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• pp.47-54
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• 2006

In order to reduce traffic accidents, many researchers studied a traffic accident model. The Cause of traffic accidents is usually the mis calculation of traffic signals or bad traffic intersection design. Therefore, to analyse the cause of traffic accidents, it takes effort. This paper, it calculates the optimal safe car speed considering intersection conditions and weather conditions. It will recommend calculation of 1/3 in vehicle speed when there are rainy days and snow days. But the problem is that it will always display the same speed limit when whether conditions change. In order to solve these problems, in this paper, it is proposed the calculation of optimal safety speed algorithm uses weather conditions and road conditions. Computer simulations is prove that it computes the traffic speed limit correctly, which proposed considering intelligent traffic accident prediction algorithms.

• Journal of the Korea Society of Computer and Information
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• v.25 no.3
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• pp.117-127
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• 2020

Recently, proving insurance fraud has become increasingly difficult because it occurs intentionally and secretly via organized and intelligent conspiracy by specialists such as medical personnel, maintenance companies, insurance planners, and insurance subscribers. In the case of car accidents, it is difficult to prove intentions; in particular, an insurance company with no investigation rights has practical limitations in proving the suspicions. This paper aims reveal that the detection of organized and conspired insurance fraud, which had previously been difficult, could be dramatically improved through conspiring insurance fraud detection modeling using social network analysis and visualization of the relation between suspected group entities and by seeking developmental research possibilities of data analysis techniques.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.8
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• pp.872-879
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• 2010

This paper describes the design for radiation pattern directivity of vehicle license plate RFID tag antenna to improve the readable range. Directivity pattern of the proposed passive antenna is decided by the meander line position and the bumper size attached to the tag antenna. In order to prove the verification of the calculated directivity pattern and readable range of the proposed antenna, the tag antenna has been fabricated and measured at the anechoic chamber. It is shown that the maximum directivity gain of the measured radiation pattern of active and passive tag antenna were observed 2.32 dBi and 3.1 dBi, respectively. The maximum readable range of passive tag antenna was measured about 8.5 m at ${\pm}45^{\circ}$ beam direction on the basis of the driving car direction($0^{\circ}$ of azimuth angle).

• Journal of Korean Society for Quality Management
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• v.46 no.2
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• pp.269-282
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• 2018

Purpose: The purpose of this study was to improve the FRP Van's durability by analyzing the problematic parameters, redesigning the rear van, and verifying the design drafts using the CAE analysis & Rig test. Methods: The collected data through the government quality inspection and field spot check were thoroughly analyzed through the characteristics diagram and the improvement suggestions were verified by performing CAE analysis, like the dynamic stiffness, Torsional stiffness, open/close condition's strength, Full car durability and Carrying out the actual test. Results: The results of this study are as follows; The output of CAE analysis shows that improvement suggestions have considerable effects on the reinforcement of FRP structure, and the actual torsion and open/close condition durability test prove that rear van may have durable life which is equivalent to vehicle life cycle. Conclusion: The structural weakness of KLTV's FRP rear van was overcome by applying the stiffener in rear van and changing the bonding method of each FRP pieces. That suggestions were proved using CAE analysis and Rig test.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.2
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• pp.1-10
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• 1989

In this paper, dynamic response of a truss bridge due to constantly moving train loads is analysed. Dynamic response of the bridge is found by the mode superposition method with the solution of the eigenvalue problem by Householder transformation and QL algorithm. To prove the validity of the analysis procedure, the response due to a very slowly moving load is compared with the result from the static analysis program, and the dynamic response is also compared with the result from the direct integration method. Based upon this, the variation of dynamic amplification factors is investigated by changing the train types and speeds, and the result is compared with the code specified impact factor. From this study, it was known that the dynamic amplification factor is not quite different by train types in low speeds but in high speeds it is, and in the case of electric car and U. I. C. loads the factor could exceed the code specified impact factor depending upon the speed.