• 자동차안전학회지
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• 제5권1호
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• pp.25-30
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• 2013

The main purpose of this research is to predict dynamic behavior of door locking system for side impact safety and the design process to avoid door opening is introduced. The equations of motion that represent the system are obtained from the energy equation. From them, the motion of door handle is predicted by using Runge-Kutta $4^{th}$ order method and the simulation result is compared with the real crash data. Also, the design guide to define the properties of door locking system from the standpoint of avoiding door opening phenomenon is introduced.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2002년도 추계학술대회 및 정기총회
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• pp.106-111
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• 2002

진화 알고리즘은 생물의 유전적 진화 과정을 이용한 새로운 문제 해결의 방안으로 결정론적 방법으로 해결하지 못한 난제에 적합한 알고리즘으로 알려져 있다. 본 논문에서는 진화 알고리즘의 연구를 기반으로 전달함수 출력 파형 검출을 위한 기법에서 이용되고 있는 런지-커타(Runge-Kutta) 방법에서의 상미분 방정식의 해를 구하는 기법 연구와 유전 알고리즘을 이용하여 Manabe 표준형의 일반화를 이용-i:l여 플랜트의 성능을 충족시키는 제어기를 설계할 수 있는 알고리즘을 구현한다. 본 논문에서의 프로그램 구현은 자바 언어를 이용하며, 자바 언어를 적용한 구현 방법과 유전 알고리즘의 효율적 기법을 제시한다.

• 한국연소학회지
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• 제1권2호
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• pp.41-49
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• 1996

A numerical study is conducted to investigate the periodically unstable shock induced combustion around blunt bodies in stoichiometric hydrogen-air mixtures. Euler equations are spatially discretized by upwind-biased third order scheme and temporally integrated by Runge-Kutta method. Chemistry model used in this study involves 8 elementary kinetics steps and 7 species. At a constant Mach number, the effects of projectile size, inflow pressure and inflow temperature are examined with Lehr#s experimental condition as a reference. In addition to oscillation frequency, characteristic distances and time averaged values are found from the result to find an relation with dimensionless parameters. As a result, it is found that the effects of inflow pressure and body size are very similar and $Damk{\ddot{o}}hler$ number plays an important role in determining the instability characteristics.

• Steel and Composite Structures
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• 제17권5호
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• pp.721-734
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• 2014

In the current study, we consider a new class of analytical periodic solution for free nonlinear vibration of mechanical systems. Hamiltonian approach is applied to analyze nonlinear problems which occur in dynamics. The proposed method doesn't have the limitations of the classical methods and leads us to a high accurate solution by only one iteration. Two well known examples are studied to show the convenience and effectiveness of this approach. Runge-Kutta's algorithm is also applied and the results of it are compared with the Hamiltonian approach. High accuracy of the proposed approach reveals that the Hamiltonian approach can be very useful for other nonlinear practical problems in engineering.

• 한국정밀공학회지
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• 제12권4호
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• pp.127-134
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• 1995

The dynamic characteristics of a system can be critically influenced by system uncertainty, so the dynamic system must be analyzed stochastically in consideration of system uncertainty. This study presents a generalized stochastic model of dynamic system subjected to bot external and parametric nonstationary stochastic input. And this stochastic system is analyzed by a new stochastic process closure method and moment equation method. The first moment equation is numerically evaluated by Runge-Kutta method. But the second moment equation is founded to constitute an infinite coupled set of differential equations, so this equations are numerically evaluated by cumulant neglect closure method and Runge-Kutta method. Finally the accuracy of the present method is verified by Monte Carlo simulation.

• 대한전자공학회논문지
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• 제19권6호
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• pp.55-61
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• 1982

집적 광학에서 응용되는, 주기가 거의 선형으로 변하는 도파로 격자 필터의 파장에 따른 응답을 격자의 길이가 유한함을 고려하여 수식적으로 구하였다. 이 필터가 광대역 필터로서 설계되는 보편적인 경우에 대해서는 관련된 포물주면 함수를 변수의 위상에 따라 점근 근사를 취함으로써 파장에 따른 응답을 간단한 함수들로써 나타냈다. 또한 구한 결파식들이 기존 근사식들을 특별한 경우로 포함하는 일반적인 식임을 보였다. 마지막으로, 수식적인 해에 의한 결과와 RunRe-Kutta 수치 계산법에 의한 정확한 해를 비교하여 서로 잘 일치함을 확인하였다. An analytic solution for the spectral response of linearly-chirped grating filter is derived, which takes the finite physical length of filter into account. In the usual case of broad-band linearly-chirped grating filter the analytic solution is expressed in terms of elementary functions, by approximating asymptotically the involved parabolic cylinder functions over different ranges of its argument. It is also shown that derived results are general enough to include previously-available approximations as particular cases, and that they agree well with the numerical solutions based upon the Runge-Kutta method.

• 한국컴퓨터정보학회논문지
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• 제8권3호
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• pp.66-72
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• 2003

상미분 방정식은 물리학, 기계학, 전기학, 열역학 등에 많이 이용되는 방정식이나 수식이 복잡하고 처리 속도가 늦어서 실시간 처리에 어려움이 많다. 그래서 이 논문에서는 소프트웨어적인 방법으로는 많은 계산량으로 인하여 처리 속도가 떨어지므로 시스토릭어레이를 이용하여 Runge-Kutta 방법으로 상미분 값을 구하는 새로운 하드웨어를 제안하였다. 이 제안한 하드웨어는 처음 셀에서의 입력이 연속적으로 각 셀을 거치면서 처리되어 마지막셀에서는 상미분 값을 얻을 수 있다. 이렇게 처리함으로서 기존의 소프트웨어적인 방식에 비하여 수렴 속도도 빠르고 정확한 근사 값을 구할 수 있으므로 실시간 처리에 많이 이용될 수 있을 것이며, 기존의 다른 수치처리를 하는 하드웨어와 통합하여 사용될 수 있다. 이 논문에서는 제안한 하드웨어를 시뮬레이션하여 정확한 결과가 나오는 것을 확인하였다.

• 대한수학회보
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• 제29권1호
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• pp.31-40
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• 1992

We introduce the generalized Runge-Kutta methods with the exponentially dominant order .omega. in [3], and the convergence theorems of the generalized explicit Euler method are derived in [4]. In this paper we will study the convergence of the generalized implicit Euler method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.680-689
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• 2011

A dynamic analysis procedure is developed to provide a comprehensive estimation of the dynamic response spectrum for locomotive's wheels running over a Pre-Stressed Concrete (PSC) box girder bridge on the Korea high speed railway. The wheel force spectrum with the bridge behavior are analyzed as the dynamic procedure for various running speeds (50~450km/h). The high-speed railway locomotive (KTX) is used as 38-degree of freedom system. Three displacements(vertical, lateral, and longitudinal) and three rotational components (pitching, rolling, and yawing). For one car-body and two bogies as well as five movements except pitching rotation components for four wheel axes forces are considered in the 38-degree of freedom model. Three dimensional frame element is used to model of the PSC box girder bridges, simply supported span length of 40m. The irregulation of rail-way is derived using the exponential spectrum density function under assumption of twelve level tracks conditions based on the normal probability procedure. The dynamic responses of bridge passing through the railway locomotive with high-speed analyzed by Newmark-${\beta}$ method and Runge-Kutta method are compared and contrasted considering the developed models of bridge, track and locomotive comprehensively. The dynamic analyses of wheel forces by Runge-Kutta method which are able to analyze the forces with high frequency running on the bridge and ground rail-way are conducted. Additionally, wheel forces spectrum and three rotational components of vehicle body for three typical running speeds is also presented.

• 한국전산유체공학회지
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• 제19권3호
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• pp.91-97
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• 2014

A high resolution numerical method aimed at solving cavitating flow was proposed and applied to gas-liquid two-phase shock tube problem with arbitrary void fraction. The present method with compressibility effects employs a finite-difference 4th-order Runge-Kutta method and Roe's flux difference splitting approximation with the MUSCL TVD scheme. The Jacobian matrix from the inviscid flux of constitute equation is diagonalized analytically and the speed of sound for the two-phase media is derived by eigenvalues. So that the present method is appropriate for the extension of high order upwind schemes based on the characteristic theory. By this method, a Riemann problem for Euler equations of one dimensional shock tube was computed. Numerical results of high speed flow phenomena such as detailed observations of shock and expansion wave propagations through the gas-liquid two-phase media and some data related to computational efficiency are made. Comparisons of predicted results and solutions at isothermal condition are provided and discussed.