• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1213-1218
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• 2007

The brake judder comes from non-uniformities in the tire/wheel assembly caused by mechanical effects such as a brake torque variation (BTV). A disc thickness variation (DTV) related with the kinematic behavior of the disc was investigated a main source of BTV. In this study, a dynamic model with brake corner assembly of full vehicle using MSC.ADAMS was correlated by experiment of judder phenomenon. Judder was generated and correlated systematically by judder experiment in chassis and brake dynamometer from variation in the thickness of the disc. Also it has been found a judder transfer path and variation of the braking pressure. Through analysis of transfer function and movement of subsystem caused by BTV generation, design parameters have been found. Based on the results obtained from parameter study of suspension module, the effective design process and developed model with brake corner assembly was suggested for vibration reduction of steering wheel caused by the judder phenomenon.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.1232-1240
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• 2001

In this study. a computer simulation of the Korean High Speed Prototype Test Train was performed to investigate the dynamic behavior(running stability. safety and comfort) in detail design process. The simulation model which was prepared by ADAMS/Rail V10.l consists of power car and middle car assembly (2 motorized cars ＋ 3 trailer cars). The nonlinear analysis takes into account the full vehicle model including wheel/rail contact and the influence of disturbed track. Throughout the dynamic calculation of KHST on the straight and the curved track. accelerations in car body. ride comforts and wheel rail forces were investigated.

• 산업기술연구
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• 제20권B호
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• pp.105-113
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• 2000

Air springs are now widely used in bus or truck suspensions due to their advantages over conventional metal spring as coil or leaf springs. Air springs have soft spring rates, which give better ride quality, and additional leveling system provides constant ride height and maintains almost same vertical natural frequencies. A mathematical model of an air spring suspension system with height control system is constructed and dynamic responses of the suspension system are investigated in the light of leveling valve motion characteristic, vertical motion natural frequency. Also, using a full vehicle model, handling characteristics of an air spring suspension is studied and the results are compared with real test results, which shows good agreements.

• 한국자동차공학회논문집
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• 제11권1호
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• pp.104-111
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• 2003

The performance of shock absorber is directly related to the car behaviour and performance, both for handling and comfort. In this study, a mathematical nonlinear dynamic model and computational method are introduced to study the flow and performance of shock absorber. The flow characteristics of components(piston and body valve) are investigated and applied to dynamic modeling of shock absorber to predict the damping force. The simulation results agree with the test data well. The shock absorber model proposed in this paper is applicable as a part of a full vehicle suspension simulation.

• 대한한의학방제학회지
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• 제15권2호
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• pp.99-111
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• 2007

In the present study, the anti-inflammatory effect of "Jungcheonhwadamgangki-tang ga Antler" water extract was tested in Xylene-Application mouse ear acute inflammation model. The test articles were once dosed before Xylene-Application, and the changes on body weight and ear weights and histopathological observation of induced ear were conducted with ear histomorphometry. The obtained results were as follows. The increases of absolute and relative ear weight detected in vehicle control compared to that of sham, were significantly and dose-dependently inhibited by Jungcheonhwadamgangki-tang ga Antler in the present study. A classic acute inflammatory histological changes such as subcutaneous edema, thickness and infiltration of inflammatory cells, was detected in vehicle control. However, these histological changes were significantly and dose-dependently inhibited by Jungcheonhwadamgangki-tang ga Antler. In addition, the increases of ear thickness half and thickness full detected in the vehicle control were also dose-dependently decreased in the all Jungcheonhwadamgangki-tang ga Antler-dosing groups. Base on these results, it is concluded that Jungcheonhwadamgangki-tang ga Antler extracts has clear anti-inflammatory effect on the acute inflammation such as bronchial asthma.

• 동의생리병리학회지
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• 제20권4호
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• pp.985-991
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• 2006

In the present study, the anti-inflammatory effect of Haepyoeiin-tang plus Antler water extract water extract was tested in Xylene-Application mouse ear acute inflammation model. The test articles were once dosed before Xylene-Application, and the changes on Dody weight and weights and histopathological observation of induced ear were conducted with ear histomorphometry, The increases of absolute and relative ear weight detected in vehicle control compared to that of sham, were significantly and dose-dependently inhibited by Haepyoejin-tang plus Antler in the present study, A classic acute inflammatory histological changes such as subcutaneous edema, hypertrophy and infiltration of inflammatory cells, was detected in vehicle control. However, these histological changes were significantly and dose-dependently inhibited by Haepyoeiin-tang plus Antler. In addition, the increases of ear thickness half and thickness full detected in the vehicle control, were also dose-dependently decreased in the all Haepyoeiin-tang plus Antler-dosing groups. Base on these results, it is concluded that Haepyoeiin-tang plus Antler water extracts have a clear anti-inflammatory effect on the acute inflammation. However, somewhat lower anti-inflammatory effects were detected in Haepyoeiin-tang plus Antler water extracts compare to that of Dethamethason and Dicrofenac. About 500 mg/kg of Haepyoeiin-tang plus Antler water extracts have similar effect compared to that of Dicrofenac 15 mg/kg.

• 동의생리병리학회지
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• 제20권4호
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• pp.875-881
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• 2006

In the present study, the anti-inflammatory effect of 'Jungcheonhwadamgangki -tang' water extract was tested in Xylene-Application mouse ear acute inflammation model. The test articles were once dosed before Xylene-Application, and the changes on body weight and ear weights and histopathological observation of induced ear were conducted with ear histomorphometry. The increases of absolute and relative ear weight detected in vehicle control compared to that of sham , were significantly and dose-dependently inhibited by Jungcheonhwadarn -gangki-tang in the present study. A classic acute inflammatory histological changes such as subcutaneous edema, hypertrophy and infiltration of inflammatory cells, was detected in vehicle control. However, these histological changes were significantly and dose-dependently inhibited by Jungcheonhwadam-gangki-tang. In addition, the increases of ear thickness half and thickness full detected in the vehicle control, were also dose-dependently decreased in the all Jungcheonhwadamgangki-tang-dosing groups. Base on these results, it is concluded that Jungcheonhwadamgangki-tang water extracts have clear anti-inflammatory effect on the acute inflammation, and about 500 mg/kg of Jungcheonhwadamgangki-tang water extracts have similar effect compared to that of Dicrofenac 15 mg/kg.

• 한국CDE학회논문집
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• 제18권1호
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• pp.21-27
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• 2013

Presented in the paper is a log data based modeling method for effective construction of a virtual plant model which can be used for the virtual PLC (Programmable Logic Controller) simulation. For the PLC simulation, the corresponding virtual plant, consisting of virtual devices, is required to interact with the input and output symbols of a PLC. In other words, the behavior of a virtual device should be the same as that of the real device. Conventionally, the DEVS (Discrete Event Systems Specifications) formalism has been used to represent the behavior a virtual device. The modeling using DEVS formalism, however, requires in-depth knowledge in the simulation area, as well as the significant amount of time and efforts. One of the key ideas of the proposed method is to generate a plant model based on the log data obtained from the production system. The proposed method is very intuitive, and it can be used to generate the full behavior model of a virtual device. The proposed approach was applied to an AGV (Automated Guided Vehicle).

• 방송공학회논문지
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• 제19권6호
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• pp.798-809
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• 2014

본 논문에서는 블랙박스 혹은 운전석에 장착된 카메라로부터 얻어진 차량 영상에 대한 영역별 수직 투영 히스토그램 매칭 및 선형 회귀분석 모델을 활용한 강건한 차량 운행 동영상의 안정화 기법을 제안한다. 동영상 안정화 기법은 영상의 흔들림 보정 뿐 아니라 동영상 내 강건한 특징점 추적 및 매칭을 위한 이전의 전처리 과정으로 활용된다. 일반적으로 촬영 과정에서 많은 떨림이 포함될 수 있는 야외 CCTV 영상이나 손으로 들고 촬영된 동영상에 대한 흔들림 보정 등에 적용되고 있으나 영상 내 특징점이 지속적으로 변하고 영상의 변화 정도가 매우 심한 차량 운행 동영상에서는 적용된 사례가 드물다. 본 연구에서는 일반적인 비디오 안정화 기술이 적용되기 어려운 차량 운행 동영상에 대하여 흔들림 보정을 위한 동영상 안정화 기법을 제안한다. 제안된 기법은 입력 영상에 대한 영역별 수직 투영 히스토그램 매칭을 수행하고 선형 회귀모델을 통해 영상에 나타나는 수직 및 회전 이동 변환을 선형 근사하여 시간 영역상에서의 입력 영상에 대한 안정화를 수행한다. 제안 방법의 검증을 위해 블랙박스로 촬영된 동영상에 동영상 안정화 기술을 적용하였으며, 운행 중 불규칙한 노면으로 인한 영상의 흔들림이 효과적으로 제거되는 것을 확인할 수 있었다.

• 대한기계학회논문집A
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• 제34권8호
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• pp.1113-1118
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• 2010

차량의 내장부품 설계에 있어 내장 부품의 탑승자 보호를 위한 FMVSS 201 법규에 따른 FMH 충격성능 만족을 위한 충격흡수구조 설계 방법이 필요하다. 충격흡수구조 설계 과정에 있어 FMH 충격 성능은 헤드라이닝의 타격 위치 및 헤드폼의 접근각에 따라 위치별로 각각 다르게 설정되며, FMH 충격 흡수부재는 위치에 따른 차체의 강성 및 상관부품을 고려하여 각 타격 위치에 따른 적절한 충격 흡수 성능을 가져야 하며 차체 강성의 변화를 고려한 효율적인 설계 방법이 필요하다. 본 연구에서는 충격 흡수구조 설계 과정에 있어 초기 설계안에 대한 충격 강도 검토의 시간을 줄이기 위해 전차량 시뮬레이션에서 수행하던 FMH 충격흡수부재 설계를 단위 모델의 압궤 시뮬레이션을 통해 진행함으로써 보다 빠르고 효율적으로 타격 위치별 적합한 충격 흡수구조를 설계하는 방법을 검토하였다.