• 대한기계학회논문집A
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• 제24권6호
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• pp.1438-1445
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• 2000

To determine dynamic characteristics of materials, a program was developed under base of stress wave propagation theory for SHPB with explicit finite element method. Through the program, all kinds of quasi-static stress-strain curves can be directly converted to dynamic stress-strain curves at any strain rate. This simulation results were compared with experimental results in the references and they are in a good agreement with each other.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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• pp.473-479
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• 2009

Dynamic analysis is necessary for the High-Speed Railway vehicle which aims to run on max 400km/h. Especially, dynamic simulation using CAE(Computer Aided Engineering) can help to reduce the time of development of the High-Speed Railway vehicles. Also, it helps to reduce prices and improve the quality such as safety, stability and ride. There are many dynamic software for a railway vehicle, such as Vampire and ADAMS-Rail. There are limitations for each software and difficulties to analyze overall dynamics for entire railway system. To overcome these limitations, in this study, a program which can simulate entire railway vehicles was developed. This program is easy to use because it was developed using C++, which is object-oriented programming language. In addition, the basic platform for the development of dynamic solver is prepared using the nodal, modal coordinate system with a wheel-rail contact module. Rigid, flexible and large deformable body systems can be modeled by a user according to the characteristic of a desired system. Its reliability is verified by comparison with a commercial analysis program.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.476-480
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• 2003

This paper presents an effective method to analyze the dynamic characteristics for the shilling transients of power transmission system using the multibody dynamics, which is composed of subsystem equation, subsystem assemble, and the self-determining technique for the system degree of freedom. Using the advantages of multibody dynamics, the proposed method can be used easily for mathematical models of mechanical systems, such as a power transmission, compared with newtonian method. With this theory, dynamic simulation program was developed. The program can be used to verify system performances, transient phenomena, and other dynamic problems. The simulation of a target system was presented, and its validity was attained by being compared with the previous analysis using newtonian method.

• 한국자동차공학회논문집
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• 제12권6호
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• pp.175-181
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• 2004

This paper presents the main method to analyze the dynamic characteristics of power transmission system using the multi-body dynamics, which is based on the concept of subsystem equation, subsystem assembling, and the self-determination technique for the system degree of freedom. We can model the mechanical components of power transmission system easily with the advantage of multi-body dynamics. Based on the theory, a dynamic simulation program was developed to analyze system performances, transient phenomena, and other dynamic problems. The driving performance of automatic transmission was simulated with using the multi-body dynamics and Newtonian method, and the validity of program was proved by comparing the two kinds of result.

• 한국터널지하공간학회 논문집
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• 제11권2호
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• pp.163-174
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• 2009

대형 지하구조물은 지진 시 지하구조물 자체의 동적특성보다는 주변 지반의 동적특성과 지하구조물의 체적에 더 큰 영향을 받는다. 따라서 본 연구의 목적은 다양한 내진해석 영향 인자들(지반조건-Q값, 지반의 동적 특성치, 단면 형상비 및 체적, 지하구조물 동적 특성치, 및 내진등급)을 포함하고 있는 대형 지하구조물의 대표적인 캐번(Cavern)에 대해 수치해석 프로그램(SAUS: 지하구조물 지진 해석 프로그램)을 이용하여 내진해석을 수행하는 것이다. 본 연구 결과 단면형 상 비의 변화에 따라서 최대 변형률, 최대 모멘트, 최대 전단력에 별 영향을 주지 못한 반면에 지반조건(Q값), 지하구조물의 체적변화, 및 내진등급에는 상당히 만감하게 반응을 하였다. 본 연구의 결과를 기초로 내진 해석의 영향 인자들의 평가가 가능해졌다.

• 한국항공우주학회지
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• 제49권1호
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• pp.31-40
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• 2021

현대의 항공기는 고성능이면서도 경량이다. 그래서 유연한 구조물의 특성이 나타나며 비행 성능에 영향을 미치거나 한계를 짓기도 한다. 이러한 유연 특성은 항공기 설계 초기 단계부터 분석이 필요한데, 이를 위해 유연 항공기의 동적·정적 거동을 분석할 수 있는 프로그램을 개발하였으며, 그 결과를 제시한다. 다물체 동역학 시뮬레이션 기법에 기반하여, 강체 비행 역학, 구조 진동 거동, 그리고 비정상 공기력 등을 세부 모듈로 개발하고 통합하였다. 마지막으로, 통합 시뮬레이션 프로그램을 이용하여 유연 특성 항공기의 등속 수평 비행과 선회비행을 분석하였다.

• International Journal of Air-Conditioning and Refrigeration
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• 제12권3호
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• pp.113-122
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• 2004

In case of heat exchangers operating under frosting condition, the thermal resistance and the air-side pressure loss increase with a growth of frost layer. In this paper, a transient characteristic prediction model of the heat transfer for a multi-inverter heat pump with frosting on its surface was presented by taking into account the change of the fin efficiency due to the growth of the frost layer. This dynamic simulation program was developed for a basic air conditioning system composed of an evaporator, a condenser, a compressor, a linear electronic expansion valve, and a bypass circuit. The theoretical model was derived from measured heat transfer and mass transfer coefficients. We also considered that the heat transfer performance was only affected by the decrease of wind flow area. The calculated results were compared with the experimental results for frosting conditions.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1905-1913
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• 2011

The dynamic characteristic of bogie that is driving system of railway vehicle is very important regarding decision of vehicle characteristics as running safety and comport. The dynamic characteristic test of bogie is tested on full size in place on field testing on track. But, the testing on the full size caused many problems. To overcome these problem by full size test, the Railway Safety Research Center in Seoul National University of Science & Technology developed 1/5 scale size of small scale derailment simulator and is currently testing running stability of 1/5 scaled bogie. Also To take effectively advantage of running stability test using small scale derailment simulator in actuality design and reliability estimation, it is necessary comparison and examination with field test and theoretical analysis result In this paper. to achieve running stability analysis of 1/5 scaled bogie on small scale derailment. the program using MATLAB that is fast compose and analysis the motion equation of Saemaul power bogie is developed. It is achieved analysis according to various specification (weight, size, suspension, etc..) and is evaluated corelation between test result and dynamic characteristic of actual railway vehicle.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.343-353
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• 1997

This study had been performed to estimate for vibration characteristics of the Power Motor Coaches with Diesel-Hydraulic Drive and to secure a dynamic characteristic construction technology of another rolling stock. Air bags, springs and dampers of Bogie are carefully reviewed in order to improve ride quality. Dynamic analysis had been performed using VAMPIRE program, which had been developed by BRR, and the analysis results had been compared with test data to verify.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.329-330
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• 2013