• Journal of Auto-vehicle Safety Association
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• v.5 no.2
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• pp.11-16
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• 2013

This paper presents a unified control algorithm of independent braking and steering for collision avoidance. The desired motion of the vehicle in the yaw plane is determined using the probabilistic risk assessment method based on target state estimation. For the purpose of coordinating the independent braking and steering, a non-linear vehicle model has been developed, which describes the vehicle dynamics in the yaw plane in both linear and extended non-linear ranges of handling. A control allocation algorithm determines the control inputs that minimize the difference between the desired and actual vehicle motions, while satisfying all actuator constraints. The performance of the proposed control algorithm has been investigated via computer simulations conducted using the vehicle dynamics software CARSIM and Matlab/Simulink.

• Journal of Auto-vehicle Safety Association
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• v.12 no.2
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• pp.27-32
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• 2020

This paper presents steering system requirements to ensure the stabilized lateral control of autonomous driving vehicles. The two main objectives of a lateral controller in autonomous vehicles are maintenance of vehicle stability and tracking of the desired path. Even if the desired steering angle is immediately determined by the upper level controller, the overall controller performance is greatly influenced by the specification of steering system actuators. Since one of the major inescapable traits that affects controller performance is the time delay of the steering actuator, our work is mainly focused on finding adequate parameters of high level control algorithm to compensate these response characteristics and guarantee vehicle stability. Actual vehicle steering angle response was obtained with Electric Power Steering (EPS) actuator test subject to various longitudinal velocity. Steering input and output response analysis was performed via MATLAB system identification toolbox. The use of system identification is advantageous since the transfer function of the system is conveniently obtained compared with methods that require actual mathematical modeling of the system. Simulation results of full vehicle model suggest that the obtained tuning parameter yields reduced oscillation and lateral error compared with other cases, thus enhancing path tracking performance.

• Journal of Auto-vehicle Safety Association
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• v.12 no.2
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• pp.7-13
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• 2020

Recently, there is a big issue of downsizing on brake system according to fuel efficiency and regenerative braking cooperation control. Especially, small cars have improved in a variety ways such as electric vehicle and smart car compared to previous small cars. So, small brake system is strongly required in the car industry. A new small brake system for light compact vehicles was proposed in this paper. For this system, the solid type disc and caliper were newly developed. And the important design factors were considered to reduce brake size. First, we calculated the temperature rise of disc through heat capacity formula and CAE analysis. Second, we analyzed the housing and carrier stiffness of caliper to select the reasonable condition. Finally, the superiorities of the developed brake system were verified by heat capacity, consumption liquid level, braking feeling, judder, wear test and regenerative braking cooperation control analysis. A developed brake system is expected to be useful for brake system of light compact platform.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.3
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• pp.49-55
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• 1996

Recently, the necessity for more accurate automatic gauge control has increased of customers' requirement for cold rolled steel sheets with thinner gauge and better gauge quality. Therefore, many cold rolling mills replaced its electric screw down automatic gauge control system with a new hydraulic automatic gauge control system, to ensure closer gauge tolerance. In this paper, The performance of a hydraulic automatic gauge control system for cold rolling has been investigated under industrial conditions. It was investigated that variation of gauge deviation according to the final products thickness, cold rolling speed and pass number, in the actual rolling mill. As a result, it was found that the system enables strip thickness variation to be reduced substantially and caused by poor gauge deviation have been drastically decreased. The test results are as following. The more the exit steel strip thickness is thick, the smaller the aguge deviation rate is large, and the more it is thin, the large the gauge deviation rate is large. Because the gauge deviation is larger at accleration speed and deceleration speed than steady speed, so automatic gauge control system is better to adopt over 50m/min. automatic gauge control system reduces rapidly large thickness deviation.

• 월간 기계설비
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• no.11 s.184
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• pp.57-71
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• 2005

SHOP DWG의 현주소 어디까지 왔는가? 설계에서 제조에 이르는 전 과정을 컴퓨터로 제어하고 관리하는 기술. 캐드(CAD)와 캠(CAM)은 각각 computer-aided design,computer-aided manufacturing의 약칭으로 컴퓨터보조설계와 컴퓨터보조생산을 뜻한다. CAD는 설계도면을 한 장씩 수작업으로 제도하지 않고 설계 데이터베이스의 정보를 CRT(cathode ray tube)에서 화상을 보고 합성하면서 설계하므로 작업을 최적화 할 수 있다. CAD로 설계된 설계도의 내용은 CAM을 통해 NC(수치제어)공작기계에 정확한 작업동작을 지시하게 되며, 작업관리∙가공∙조립∙검사 등의 제조과정을 컴퓨터로 관리하여 작업속도와 제품의 정밀성을 높이게 된다. 최근에는 건축현장의 2D system이 보편화되어 있지만 건축현장의 핵심이라고 할 수 있는 기계설비의 기계실, 또는 조립화 공법 등에는 3차원 CAD∙CAM시스템이 개발되어 입체형상을 화면에 3차원으로 재현할 수 있고, 대상물의 표면적∙부피∙무게∙강도 등의 물리적 성질도 자동 계산하여 최적상태에서 현장의 시공에 적용할 수 있게 되었다. 1960년대 초 미국에서 자동차 모델∙엔진, 항공기 부품 등 의 설계에 수작업의 한계를 느껴 개발되었으며, 한국에서는 70년대 중반에 도입되어 운용되고 있다. 이에 따라 프로그램 회사들은 다양한 방법 등을 SHOP DWG에 적용하여 판매경쟁이 치열하다. (주)우진아이엔에스는 급속한 산업경제의 변화와 무한경쟁시대에 보다 나은 기술개발 투자에도 노력을 기울여, 2000년 11월 용인공장, 생산라인을 천안으로 이전, 확장 하여 배관 및 닥트의 CAD-CAM SYSTEM, P.F.P공법, 기계실3D, 블럭화배관, 닥트자동화 시스템, 설계, 용접공정을 공장화시켰으며, 신 개발품인 S.C.D(SEMI-CON DUCT)를 신설하여 모든 건축물에 맞는 필수적인 제품을 생산함으로써 선택의 폭을 넓히고, 현장 시공능력 효율을 높이고 있다. 이번 호에서는 (주)우진아이엔에스가 95년 설계팀을 발족하여 제로시스템의 3D공법을 공장 및 현장의 SHOP DWG에 적용해왔고 최근에는“서초 프로젝트A”현장에 SHOP DWG의 최대 결집체인 3D활용의 조립화 공법을 적용하여 초고층 오피스텔현장을 시공한 사례를 게재한다. 우진아이엔에스는 30여년의 기술 축척을 바탕으로 최고의 기술력과 풍부한 경험을 통해 아셈무역센타, 타워팰리스1차, 3차 및 목동트라팰리스, 분당트리폴리스, 수원삼성전자 R4, 등 국내굴지의 초고층빌딩 시공을 근거로 초고층의 기본설계를 이해하고 SHOP DWG을 통해서 기계설비공사의 향후 나아갈 지표를 제시하고 있다.

• The Transactions of the Korean Institute of Power Electronics
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• v.2 no.1
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• pp.33-38
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• 1997

Generally, various semiconductor switching devices for power systems are used in battery chargers for electric vehicle. When these used, it takes the problems of transient-current or distortion of waveforms in power systems near by battery chargers because of harmonics and large peak-current, low power factor, etc., caused by the non-linearity of these devices. Recently, power factor control, line current peak-cut, harmonics reduction which was ignored in past is more and more important. In this paper, to solve those problems we will improve the characteristics of voltage rising and propose the high power factor converter circuit for battery chargers. Our proposed system convert commutated voltage to AC resonant wave in high frequency inverter and rectify the link voltages passed high-frequency transformer and transfer the DC voltages. Especially, the effect using these converter system can be improved very large by power factor control and we have to verify the possibilities of improvement through the experiment of Pb-Acid battery application.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.467-470
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• 2009

CAN communication developed for communication between electric control devices in vehicle, was recently applied to automatic braking devices, and can also be applied to field bus for production automation. Recently, field bus is introduced in engine control, etc. for large ship. In this paper, cabin access control system can be implemented, based on CAN communication. The cabin access control system based on CAN communication consists of access control server, embedded system based on ARM9, and micro-controller built-in CAN controller. The access control server can be able to manage overall access control system by accessing with manager. And embedded system adopted ARM9 processor transmits access information of RFID reader controller connected with CAN networks to server, also performs access control. The embedded system can carry CAN frames to server, so it can be used as gateway.

• Journal of Auto-vehicle Safety Association
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• v.11 no.2
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• pp.35-43
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• 2019

This paper describes the improved environment recognition algorithms using some type of sensors like LiDAR and cameras. Additionally, integrated control algorithm for an autonomous vehicle is included. The integrated algorithm was based on C++ environment and supported the stability of the whole driving control algorithms. As to the improved vision algorithms, lane tracing and traffic sign recognition were mainly operated with three cameras. There are two algorithms developed for lane tracing, Improved Lane Tracing (ILT) and Histogram Extension (HIX). Two independent algorithms were combined into one algorithm - Enhanced Lane Tracing with Histogram Extension (ELIX). As for the enhanced traffic sign recognition algorithm, integrated Mutual Validation Procedure (MVP) by using three algorithms - Cascade, Reinforced DSIFT SVM and YOLO was developed. Comparing to the results for those, it is convincing that the precision of traffic sign recognition is substantially increased. With the LiDAR sensor, static and dynamic obstacle detection and obstacle avoidance algorithms were focused. Therefore, improved environment recognition algorithms, which are higher accuracy and faster processing speed than ones of the previous algorithms, were proposed. Moreover, by optimizing with integrated control algorithm, the memory issue of irregular system shutdown was prevented. Therefore, the maneuvering stability of the autonomous vehicle in severe environment were enhanced.

• Journal of Auto-vehicle Safety Association
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• v.6 no.1
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• pp.5-9
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• 2014

Over the past ten years, since the introduction of the side crash test regulation in Europe, much research work has been performed internationally to develop new and modified test procedures to improve the level of occupant protection offered by vehicles in side crash test. This research has been co-ordinated and finally contributed to development of an AE-MDB(Advanced European Moving Deformable Barrier) and WorldSID (Worldwide Side Impact Dummy). EuroNCAP(European New Car Assessment Program) has the plan to conduct AE-MDB side crash test using WorldSID from 2015 by replacing Progressive MDB and EuroSID II. Automobile manufacturers need to respond to these changes closely. This paper is to find dominant control factor and analyze it of WorldSID 50%ile dummy injury through AE-MDB side crash test by predicting best and worst condition. And control factors will be validated within EuroNCAP regulations. This paper is analyzed by DFSS(Design for six sigma) which contains 5 control factors and is evaluated by ANOVA with the data as a result of LS-DYNA analysis correlated with crash pulse from 50 kph AE-MDB side crash test using WorldSID 50%ile dummy.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.83-91
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• 2016

We studied the effect of battery deep cycle according to the way of active materials formation and the creation condition of electrode material, 3BS ($3PbO{\cdot}PbSO_4{\cdot}H_2O$) and 4BS ($4PbO{\cdot}PbSO_4$), in order to develop the batteries for Idle Stop & Go system. During the curing with active materials of anode and cathode, we found that the final creased active material was deformed by temperature control and it effects the durability of batteries. AGM battery and Flooded battery with 3BS active materials have excellent initial performance. And AGM battery with 4BS active materials shows the lower performance relatively. To compare and analyze of the formation efficiency of active materials, we tested the formation chagging steps with 3 steps and 9 steps differently. The results are that AGM battery with 4BS active materials is better on initial performance than AGM battery with 3BS. After the comparison of durability by DOD 17.5% life test, AGM battery is more suitable than flooded battery for the ISG system which needs the frequent deep cycle. In conclusion, AGM battery is the most suitable for ISG system and the life performance shows 80% difference according to the way of formation and curing of AGM batteries.