• Journal of the KSME
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• v.28 no.1
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• pp.28-36
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• 1988

차량 주행특성을 규명하기 위한 연구방법에 대한 일반적 고찰을 토대로 주요 개방회로시험과 관련 평가기준들이 소개되었다. 그러나, 차량의 주행상 안전도 연구를 위한 종합적인 척도는 이제까지 설명된 평가기준들로부터 아직 명확히 귀결지을 수 없음을 강조하여야 한다. 이유로 서는, 한편으로 응용되어진 연구방법들이 실제 교통사고 발생상황을 포괄하기에는 아직 불충분 하며, 또 한편으로는 주어진 한 시험방법에서 주행안전도 판정을 위해 제기된 특성치가 절대적인 값으로 확정지을 수 없기 때문이다. 따라서 전체 시스템 '운전자-차량-환경'에 있어서 주행특 성의 완전한 평가를 내리기 위해서는, 객관적으로 서술될 수 있는 차량의 주행특성-안정성 및 조절성과 운전자에 의한 주관적인 판별 또한 환경요소에 의한 영향들에 대하여 상호 연관관계가 복합적으로 해석. 규명되어져야만 할 것이다.

• Journal of the Korean Geotechnical Society
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• v.23 no.6
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• pp.115-126
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• 2007

The tilting-train is very attractive to the railroad users in the world because it runs with high speed in curved track using pre-existing infrastructure. The tilting-train has a unique allowable speed and mechanism expecially in curved track. Therefore, it should be evaluated in terms of the stability of the train operation and roadbed. In this study, when the tilting-train is being operated with the allowable speed, the behavior of the roadbed is evaluated by examining the settlement and bearing capacity of the roadbed. Additionally, the stability of the roadbed is estimated in the condition of soft roadbed influenced by the weather effects and cyclic train loading. The numerical results show that the roadbed settlements satisfy the allowable settlement when Young's moduli of the upper roadbed and in-situ soil are more than $2,300t/m^2\;and\;3,300t/m^2$, respectively, in the continuous welded rail (CWR) and $3,800t/m^2\;and\;4,600t/m^2$, respectively, in the rail joint.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.8
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• pp.1716-1721
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• 2005

Conventionally, 2WS is used for vehicle sleeting, which can only steering front wheel. In case of trying to high speed slalom or emergency through this kind of vehicle equipped 2WS, it may occur much of side slip angle. On the other hand, 4WS makes decreasing of side slip angle, outstandingly, so it is possible to support vehicle movement stable. And conventional ABS and TCS can only possible control the longitudinal movement of braking equipment and drive which can only availab to control of longitudinal direction. There after new braking system ESP was developed, which controls both of longitudinal and lateral, with adding of the function of controlling Active Yaw Moment. On this paper, we show about not only designing of improed braking and steering system through establishing of the integrated control system design of 4WS and ESP but also designing of the system contribute to precautious for advanced vehicle stability problem.

• Annual Conference of KIPS
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• 2023.11a
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• pp.1167-1168
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• 2023

차량용 반도체 수요의 증가로 자율 주행 및 전장제품에 시스템 반도체 수요가 증가하고 있다. 차량용 반도체는 기존 AP 같은 칩보다 더 높은 내구성과 신뢰성이 요구되기 때문에 불량 분석이 중요하다. 이러한 환경에서 반도체의 안정적인 생산과 품질 보장을 위해서는 불량 검출과 불량 원인 분석이 중요하다. 본 논문은 기본적인 비파괴 불량 분석 방법에 대하여 조사하고 장단점을 탐구한다. 이를 통해 반도체의 안정적인 양산을 위한 기반 지식을 제공한다.

• The Korean Journal of Rheology
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• v.11 no.2
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• pp.112-121
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• 1999

An MR(Magneto-Rheological) fluids damper is designed and applied to vibration suppression of a 1/4 car model. The damping constant of MR damper changes according to input current which is controlled in a semi-active way. Several control algorithms are compared in simulations and experiments. The advantage of the proposed Frequency shaped LQ control is that passenger comfort is emphasized in the range of 4~8Hz and driving safety is emphasized around the resonance frequency of unsprung mass.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.1 s.24
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• pp.29-38
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• 2007

The research on the track performance and stability of the tilting-train was performed and the settlement of the roadbed was estimated as the tilting train was being operated on the rail joint under the allowable velocity subjected to the track performance and the stability of the tilting-train. Since the impact on the continuous welded rail (CWR) induced by the tilting-train loading is different from the impact on the rail joint, it needs to investigate the settlement of the roadbed beneath the CWR. In this study, when the tilting-train is being operated on the CWR under the allowable velocity subjected to the track performance and the stability of the tilting-train, the settlement and bearing capacity of the roadbed beneath the CWR have been evaluated using numerical analysis and compared with those beneath the rail joint. The numerical results show that the settlements of the roadbed beneath CWR and rail joint are amount to 71.2% and 88.8% of the allowable settlement, respectively. And the stresses are amount to 10.4% and 12.1% of the allowable bearing capacity, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.8B
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• pp.839-845
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• 2009

The Vehicular Ad-hoc Network (VANET) has two main problems to be overcome due to high mobility and frequently changing density: one is short link duration time and the other is high packet loss ratio. To solve the problems, there have been many studies to predict vehicular mobility. Most of the studies try to enhance link expire time and link reliability, however the distance between two relay nodes becomes too short to have high network throughput. In this paper, we propose a new routing algorithm that considers both link expire time and network throughput in the VANET. The proposed algorithm aims to find path with long link expire time and high throughput. Our simulation results show that the proposed algorithm outperforms the legacy greedy algorithm and its variants.

• Annual Conference of KIPS
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• 2017.04a
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• pp.461-462
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• 2017

본 논문은 지능형 교통시스템의 상용화에 따라 점차 주목받고 있는 차량 간의 통신 과정에서 안정성이 필수적이라고 판단하였다. 그 중 현재 차량 간의 통신 과정에서 필수적으로 활용되고 있는 인증서에 대한 취약점에 주목하였고 본 논문에서는 기존의 인증서 발급 절차의 위협으로 판단되는 CA의 인증서 발급절차를 개선함으로써 CA접근에 대한 위협으로부터 안전할 수 있는 방안을 제안한다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.2
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• pp.129-137
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• 2020

Currently, The autonomous vehicle market is researching and developing four-level autonomous vehicles beyond the commercialization of three-level autonomous vehicles. Because unlike the level 3, the level 4 autonomous vehicle has to deal with an emergency directly, the most important aspect of a four-level autonomous vehicle is its stability. In this paper, we propose an Optimized Vehicle Routing System (OVRS) that determines the route with the lowest probability of an accident at the destination of the vehicle rather than an immediate response in an emergency. The OVRS analyzes road and surrounding vehicle information collected by The RSU communication to predict road hazards, and sets the route for the safer and faster road. The OVRS can improve the stability of the vehicle by executing the route guidance according to the road situation through the RSU on the road like the network routing method. As a result, the RPNN of the ASICM, one of the OVRS modules, was about 17% better than the CNN and 40% better than the LSTM. However, because the study was conducted in a virtual environment using a PC, the possibility of accident of the VPDM was not actually verified. Therefore, in the future, experiments with high accuracy on VPDM due to the collection of accident data and actual roads should be conducted in real vehicles and RSUs.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.59-67
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• 2014

A dynamic analysis is carried out to provide an evaluation method of running safety for a PSC box bridge located on the Gyung-Bu high speed railway. The numerical models of bridge and train vehicle are developed in detail with corresponding interaction system. Three dimensional skeleton element model of PSC box bridge and 38-degree-of-freedom of vehicle are adopted from the existing properties of KTX bridge and train vehicle. Analysed three direction rotations of vehicle on the bridge and ground tracks are compared for running speeds up to 500 km/h with 10 km/h constant increments. The comparison of the rotations will be an improved evaluation method of Running Safety in stead of the existing standard method.