http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
손정현(Jeong-hyun Sohn),김광석(Kwan-suk Kim),유완석(Wan-suk Yoo) 한국자동차공학회 2002 한국자동차공학회 지부 학술대회 논문집 Vol.2002 No.10
The shimmy vibration analysis of a passenger car is carried out using the computer simulations. In this paper, a hydraulic power steering system is developed using DADS user-defined subroutine and used to power steering simulation. The simulation shows that steering wheel torque with HPS module is less than that without HPS module. In addition, the shimmy vibration at the steering wheel is simulated with DADS and compared to the test data. Lateral displacement of the steering wheel is calculated imposing the lateral acceleration of the knuckle as a vibration input. The frequency response of the steering wheel shows a good agreement to the test data.<br/>
동역학 해석을 위한 고무부싱의 실험적 모델링에 대한 연구
손정현 ( Jeong Hyun Sohn ),백운경 ( Woon Kyung Baek ),김동조 ( Dong Jo Kim ) 한국고무학회 2004 엘라스토머 및 콤포지트 Vol.39 No.2
고무부싱은 차량부품들을 서로 연결하고 차체로 전달되는 진동을 줄여주는 역할을 하는 중요한 요소로써 가진변위와 주파수에 대해서 모두 비설형 특성을 보이며, 특히 주기적인 가진에 대해 히스테리시스 현상을 나타낸다. 본 논문에서는 1축 내구시험기를 이용하여 차량 현가장치에 사용되는 부싱을 축 방향과 반경 방향에 대해 사인가진과 랜덤가진을 주어 특성을 살펴보았고 이러한 특성을 반영할 수 있는 동역학적 모델을 인공신경망을 이용하여 개발하였다. 실험결과는 신경망의 입력자료로 활용되었고, 오차역전파 알고리즘을 이용하여 실험적 부싱모델을 개발하였다. 개발된 실험적 부싱모델을 차량 시abf레이션에 적용하여 유용성을 살펴보았다. A rubber bushing connects the components of the vehicle each other and reduce the vibration transmitted to the chassis frame. A rubber bushing has the nonlinear characteristics for both the amplitude and the frequency and represents the hysteretic responses under the periodic excitation. In this paper, one-axis durability test is performed to describe the mechanical behavior of typical vehicle elastomeric components. The results of the tests are used to develop an empirical bushing model with an artificial neural network. The back propagation algorithm is used to obtain the weighting factor of the neural network. A numerical example is carried out to verify the developed bushing model and the vehicle simulation is performed to show the fidelity of proposed model.
손정현(Jeong-hyun Sohn),이재욱(Jae-wook Lee),김광석(Kwang-suk Kim),유완석(Wan-suk Yoo) 한국자동차공학회 2001 한국자동차공학회 지부 학술대회 논문집 Vol.- No.-
The Jacobian matrix of the equations of motion of a system with velocity transformation technique is derived via variation methods to apply the implicit integration algorithm, DASSL. The concept of generalized coordinate partitioning is used to parameterize the constraint set with independent generalized coordinates. DASSL is applied to determine independent generalized coordinates and velocities. Dependent generalized coordinates, velocities, accelerations and Lagrange multipliers are explicitly retained in the formulation to satisfy all of the governing kinematic and dynamic equations. The derived Jacobian matrix of a system is proved to be valid and accurate both analytically and through solution of numerical examples.<br/>
손정현(Jeong-Hyun Sohn),강태호(Tae-Ho Kang),백운경(Woon-Kyung Baek),박동운(Dong-Woon Park),유완석(Wan-Suk Yoo) 대한기계학회 2004 대한기계학회 춘추학술대회 Vol.2004 No.4
In this paper, a blackbox approach is carried out to model the nonlinear dynamic bushing model. One-axis durability test is performed to describe the mechanical behavior of typical vehicle elastomeric components. The results of the tests are used to develop an empirical bushing model with an artificial neural network. The back propagation algorithm is used to obtain the weighting factor of the neural network. Since the output for a dynamic system depends on the histories of inputs and outputs, Narendra's algorithm of 'NARMAX' form is employed in the neural network bushing module. A numerical example is carried out to verify the developed bushing model.
모드좌표와 절대절점좌표를 혼용한 동역학 해석기법에 관한 연구
손정현(Jeong Hyun Sohn),유완석(Wan Suk Yoo) 대한기계학회 2003 대한기계학회 춘추학술대회 Vol.2003 No.11
In this paper, the absolute nodal coordinate formulation was introduced to describe the large deformation<br/> problems. And also, the modal coordinates were employed to represent the small elastic deformation. A new<br/> hybrid formulation was developed to combine the modal coordinates and the absolute nodal coordinates. A<br/> spherical joint and the DOT1 constraint were developed to carry out the numerical simulation of mechanical<br/> systems with kinematic joints. A beam example was suggested to show the new formulation. The simulation<br/> results using the modal coordinates and the absolute nodal coordinates show a good agreement to the<br/> experiments.
손정현(Jeong Hyun Sohn),전철웅(Chul Woong Jun) 대한기계학회 2011 大韓機械學會論文集A Vol.35 No.8
본 논문에서는 우등버스용 MR 댐퍼의 특성 시험 결과를 분석하고, 비선형 히스테리시스 특성을 모델링할 수 있는 실험적 모델링이 제시된다. MR 댐퍼의 인가전류에 따른 실험적 모델을 구성하고, 매트랩의 최적설계 툴 박스를 이용하여 계수를 규명한다. 우등버스의 전차량 시뮬레이션을 통하여 차량동역학 해석용 MR 댐퍼의 실험적 모델의 유용성을 검증한다. In this paper, we analyze the characteristic test results of an MR damper for a cruise bus, and we model the nonlinear hysteretic characteristics of the damper using arctangent and polynomial functions. We establish an experimental model of the MR damper according to the input current, and we set the model parameters using the MATLAB Optimization Toolbox. The model is verified via a computer simulation of a full-car model.
차현경(Hyun Kyung Cha),장진석(Jin Seok Jang),유완석(Wan Suk Yoo),손정현(Jeong Hyun Sohn) 대한기계학회 2014 大韓機械學會論文集A Vol.38 No.11
회로차단기에서 가장 중요한 성능은 전기시스템의 이상전류를 신속하게 차단하는 것이다. 이러한 차단시간은 조작기구의 동적 특성에 의한 영향을 받는다. 따라서 회로차단기의 차단시간 단축을 위해서는 조작기구의 최적화가 이루어져야 한다. 본 논문의 가스회로차단기의 조작기는 스프링으로 구동되며 여러 개의 Latch 로 구성되어있다. Latch 들의 상대적 위치와 길이로 정의된 각 설계변수의 차단시간에 대한 영향을 분석하고 이 결과를 통해 설계변수를 선정하여 ADAMS 와 VisualDOC 의 연동을 통해 최적화를 수행하였다. Latch 들의 최적화를 통해 약 22.5% 개극시간을 향상을 확인하였다. Breaking time is an important performance indicator of a circuit breaker. Thus, the operating mechanism of the circuit breaker should be optimized for reducing the breaking time. The operating mechanism in a gas circuit breaker is made up of several latches. Specifically, the geometry and relative positions of latches influence the dynamic behaviors of the operating mechanism. In this study, a three-stage latch operating mechanism is analyzed on the basis of the verified multibody dynamics model constructed using the MSC.ADAMS program. The relative positions and lengths of latches are selected as design variables. The dominant design variables are selected by a design study. Optimization is performed using a genetic algorithm (GA). The study results demonstrate that the performance of the circuit breaker improves by about 22.5.