• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.159-166
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• 2006

Chassis system has a large influence on ride quality, stability and NVH performance of a car. To improve the performance and reduce cost, the development of chassis modular assemblies is emphasized. To develop chassis corner modules, it is necessary to predict the performance of full vehicle motion such as ride, handling performance, NVH characteristics and durability of modules. In this paper, full vehicle test is performed to acquire the road load data of chassis corner module of passenger car. 3-axis simulator modeling are carried out to simulate reaction force analysis and fatigue analysis of new developed modules. Also, real simulator tests to validate performance of new developed modules are performed. We had developed the accelerated durability test procedure of KATECH PG and it is used to test chassis corner modules at laboratory and simulate durability performance. All these results have been provided to module and parts company and make an important role to develop chassis corner modules.

• Journal of Auto-vehicle Safety Association
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• v.14 no.3
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• pp.41-47
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• 2022

Composite material is recently very important material for eco-friendly vehicles because of its excellent mechanical property and lightweight effect. So, many research results have been recently published for developing the composite material to apply vehicles. In this paper, new brake system is presented using composite material to response this situation. And advantages in terms of performance compared to competitive company will be discussed in depth to verify superiorities of the new composite brake. To do so, composite brake systems which have the same size as the competitive company to the same vehicle is applied. And superiorities through a variety of test results are presented. First, normal braking performances are compared with competitive company through braking effect, heat capacity and friction test, Second, circuit driving and high speed fade test are also verified with competitive company to confirm harsh braking performances for the new composite brake system. Finally, the effects of applying the composite brake to automobile industry like electric car are analyzed.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.3
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• pp.149-155
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• 2010

Currently various safety tests are being performed in many countries with growing interest in vehicle safety. However the vehicles which have good safety performance in these tests could not secure the good performance in real car to car accident. So new test protocol using progressive deformable barrier (PDB) was proposed by EEVC in Europe, NHTSA in USA and some vehicle manufacturers, etc. The target of PDB test is to control partner protection in addition to self-protection on the same test. The proposal is to update current ECE R.94 frontal ODB test. So barrier, impact speed, overlap are changed to avoid bottoming-out in the test configuration. In this paper 3 different tests (R.94, EuroNCAP and PDB test) were carried out using current production vehicles with same structure. The results of these tests were compared to understand PDB test. As a result PDB test shows the highest vehicle deceleration and dummy injury because PDB offers a progressive increase in stiffness in depth and height. However vehicle intrusion was affected with rather test velocity than stiffness of deformable barrier. PDB deformation data is used for partner protection assessment using PDB software and it shows that the test vehicle is rather not aggressive.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1035-1040
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• 2004

In the proto design stage of a new car, the performance of an occupant protection system is often evaluated by CAE instead of the real test. CAE predicts and recommends the appropriate design values hence reducing the number of the real tests. However, the existing researches using CAE in predicting the performances do not consider the uncertainties of parameters, in which inconsistency between the actual test results and CAE exists. In this research, the optimization procedure of a protection system such as airbag and load limiter is suggested for the frontal collision. The DACE modeling known as Kriging interpolation is introduced to obtain the meta model of the system followed by the tabu search method to determine a global optimum. Finally, the distribution of a suggested design is determined through the Monte-Carlo Simulation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.1
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• pp.55-60
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• 2010

The honeycomb composite joint structure designed for application to a tilting KTX railroad car body is subjected to bending loads of a cantilever type. Honeycomb sandwich composite panel-joint attached in the real tilting car body was fabricated and sectioned as several beam-joint specimens for the bending test. The fracture behaviors of these specimens under static loads were different from those under cyclic loads. Static bending loads caused shear deformation and fracture in the honeycomb core region, while fatigue cyclic bend loading caused delamination along the interface between the composite skin and the honeycomb core, and/or caused a fracture in the welded part jointed with the steel under-frame. These fracture behaviors could occur in other industrial honeycomb composite joints with similar sub-structures, and be used for improving design parameters of a honeycomb composite joint structure.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.51
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• pp.199-210
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• 1999

The number of car accident is Recently on the increase in Korea because of the explosive increase of cars, the poor road condition, the lack of safety facility, and others. The insurant with a accident has to decide whether receiving a insurance or not. In this paper, we represent a reasonable decision support material by calculating the approximate insurance fee based on the discount rate and premium additive rate, which is changed by the accident type and the accident expenditure. Practically, there is difference in the standard insurance rate and premium additive rate according to the accident type and the accident expenditure in Korea. The premium additive rate is assessed considering the number of accident, the pattern of accident, and the reason of accident for 3 years. In this paper, we represent a decision making method considering not only the first-time car accident but also the future car accident. For considering the repeated accident, we analyzed the real data accumulated until the year of 1996 from S Insurance Company, and estimated the probability density function between the first and the second-time accident, and executed the goodness of fit test using ARENA and STATISTICA software. Using this conditional PDF, we can calculate the insurance fee next 3 years and compare the insurance fee with the equivalent present value of cash flows. The program performing this analysis is represented, and written in VISUAL BASIC Language. We tried to suggest an accurate guideline for the insurant to decide the insurance coverage rationally, and tried to correct a wrong idea of dependence on the car insurance only by the amount of the accident expenditure. And we expect this study can generally be applied to many different accident types under the uncertain circumstances in our daily life.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.1
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• pp.96-109
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• 1996

The airbag system is known to be extremely efficient for the protection in an automobile crash. The performance of the airbag system is evaluated by real tests. However, the test is very difficult and expensive. Therefore, the computational simulations are carried out with low cost. The airbag analysis is included in the anlysis of the full-car crashworthiness. The behavior of the airbag can be predicted by a thermodynamic analysis. The contact force between the occupant and the airbag is calculated from the contact volume and the pressure in the airbag. The injury rate is evaluated from the contact force and the acceleration of dummies. So far, the contact is defined after the airgag is fully inflated. In many cases, the occupant is seated in the out-of-position and the contact can happen during the inflation process. A new algorithm has been developed for the out-of-position. To describe the inflation process precisely, the airbag is defined by a sphere and a torus. The injury is evaluated for the contact happened at any time. The developed algorithm is coded and interfaced with an existing software in the public domain. The full-car modeling is adopted from the previous study which is tuned for the regular position and real tests. Numerical experimentation have been carried out with a couple of dummies in the out-of-position and the injury processes are analyzed.

• Korean Journal of Computational Design and Engineering
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• v.2 no.3
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• pp.133-141
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• 1997

In the process of car body design, various surfaces are generated from the given boundary curves. Depending upon the method of the surface generation and the quality of the boundary curves provided, the resulting surfaces may have global or local irregularities in many cases. Thus it would be necessary for the designer to evaluate the surface quality and to modify the surface or to use the different generation method based on the evaluation results. This capability is very important because the defect of the surface quality detected in the production stage will require the rework of the dies and will cause a big loss in cost and time. A method of surface interrogation using reflection line is introduced. In this paper, We applied reflection mapping to generate reflection lines on the trimmed NURBS surface. Since reflection lines are obtained from reflection mapping that uses simple and physically acceptable mapping algorithm, they can be efficiently used to simulate the reflection test on the real part in the production line.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2222-2224
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• 2001

This paper presents the implementation of an efficient car tracking system based on Inverted DGPS (IDGPS) using mobile phone and internet for data communication link. The IDGPS technique, which may provide the same level of accuracy as DGPS, is subject to degradation in real time applications when transmission time delays occur in the communication links. Therefore, an effective communication system is the key element for successful application of the IDGPS. The combination of internet and mobile phones provides a high data rate, unlimited communication packet size, flexible data structure, and wide coverage without additional communication devices. An implementation of such a data link system is described. Field test results are included to evaluate the performance of the proposed system.

• Journal of KIISE:Software and Applications
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• v.26 no.11
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• pp.1324-1331
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• 1999

물체의 공간에서의 운동을 다루는 공간 추론의 연구에서 충돌을 이해하는 것은 중요하다. 본 논문에서는 정성적 충돌 이론과 추론 기법을 소개하고자 한다. 충돌 해석에 있어 관련된 물체의 공간적 속성과 운동방향의 상호작용을 분석하여 충돌로 인한 힘과 운동 방향의 전달을 계산하였다. 추론 과정에 있어서는 충돌이 갖는 특성인 불연속적인 변화에 대한 분석과 회전 운동으로 인한 변화의 분석이 소개되었다. 제안된 충돌 이론과 추론 기법은 구현되어 자동차 충돌 사고의 충돌에 적용되어 유효성을 입증할 수 있었다. Abstract Understanding collision is important in spatial reasoning problems that study the motions of objects. This paper introduces qualitative collision theory and reasoning techniques. Force and motion transfers are computed by analyzing the interactions of the spatial properties and motions of the objects. This paper also presents inference techniques for handling discontinuous changes and angular changes by rotation. These theories and inference techniques are implemented and applied to real car-to-car collision accidents. The test results verify the reliabilities of our techniques.