• Journal of Mechanical Science and Technology
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• 제19권spc1호
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• pp.481-486
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• 2005

This paper introduces a numerical method for integration of the linear and nonlinear differential dynamic equation of motion. The variation of acceleration in two time steps is approximated as a combination of both trigonometric cosine and hyperbolic cosine functions with weighted coefficient. From which all necessary formulae are elaborated for the direct integration of the governing equation. A number of linear and nonlinear dynamic problems with various degrees of freedom are analysed using both the suggested method and Newmark method for the comparison. The numerical results show high advantages and effectiveness of the new method.

• 한국초전도ㆍ저온공학회논문지
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• 제16권4호
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• pp.53-56
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• 2014

A numerical method of magnetic field calculation for the air-core solenoid is presented in this paper. In application of the Biot-Savart law, the magnetic field induced from the source current can be obtained by a double integration ormula. The numerical method named composite Simpson's rule for the integration is applied to the program and the adaptive quadrature method is used to adjust the step size in the calculation according to the precision we need. When the target point is in the solenoid and the intergrand's denominator may be zeroin the process of calculation, the method sill can provide an appropriate result. We have developed a program which calculates the magnetic field with at least 1ppm precision and named it as rzBI() to implement this method. The method has been used in the design of an MRI magnet, and the result show it is very flexible and convenient.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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• pp.615-622
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• 2002

In this paper, the modification of double projection method for the adaptive analysis of Element-free Galerkin(EFG) method were proposed. As results of the double projection method, the smoothed error profile that is adequate for adaptive analysis was obtained by re-projection of error that means the differences of EFG stress and projected stress. However, it was found that the efficiency of double projection method is degraded as increase of the numerical integration order. Since, the iterative refinement to single step error estimation made the same effect as increasing of integration order, the application of the iterative refinement base on double projection method could be produced the inadequately refined analysis model. To overcome this defect, a modified scheme of double projection were proposed. In the numerical example, the results did not show degradation of double projection effect in iterative refinement and the efficiency of proposed scheme were proved.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2015년도 제52차 하계학술대회논문집 23권2호
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• pp.198-200
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• 2015

건설산업의 전자도면 작성을 위한 CAD분야는 해외 특정 소프트웨어가 시장을 90%이상 점유하여 기술종속으로 인한 CAD 기술의 자립화 문제가 심각하다. 건설산업에서 발생하는 전자도면의 작성을 위한 프로그램 사용은 자유경쟁을 통한 시장의 흐름에 따른 것이나, 공공기관에서 발주하는 건설사업의 전자도면 관리와 재활용을 위해서는 특정 회사의 과다 독점으로 인한 기술종속에 대한 대책이 필요하다. 따라서, 다양한 CAD 시스템에서 작성한 전자도면을 국내표준에 부합하는 도면으로 변환 가능한 모델러의 개발 방안을 제안한다.

• East Asian Economic Review
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• 제18권2호
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• pp.163-186
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• 2014

This paper argues that the formation of regional integration frameworks can be best understood as a dominant state's attempt to create a preferred regional framework in which it can exercise exclusive influence. In this context, it is important to observe not only which countries are included in a regional framework, but also which countries are excluded from it. For example, the distinct feature of the Trans-Pacific Partnership (TPP) is its exclusion of China, and that of the Regional Comprehensive Economic Partnership (RCEP) is its exclusion of the United States (US). An exclusion of a particular country does not mean that the excluded country will perpetually remain outside the framework. In fact, TPP may someday include China, resulting from a policy of the US "engaging" or "socializing" China rather than "balancing" against it. However, the first step of such a policy is to establish a regional framework from which the target country of engagement is excluded.

• 한국실내디자인학회논문집
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• 제15권3호
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• pp.136-143
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• 2006

This research proposes the importance of physical environment if integrated early childhood education. For a successful integration of children's education, we processed fundamental research on requirements of facility and equipments, looking at related standards and code on handicapped person's convenience facility. Also, this research alms at providing first step to establish evaluation method and quality assurance standards of integrated child care facility, regarding space planning of handicapped children. By examining home and abroad material and analyzing handicapped children's convenience facility standards, this research pursues improving the basis of planning criteria. As present criteria of relevant regulations appears not to handle detailed facility standards, and the handicapped people's facility is for childhood education, it is necessary first to differentiate indispensable equipments from optional one, then categorize them into more specific needs.

• 한국학교수학회논문집
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• 제18권2호
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• pp.223-240
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• 2015

본 논문의 목적은 미적분에 관한 보충학습을 요하는 이공계 대학생들을 위하여 공업수학의 벡터미적분 교육을 중심으로 개념적 이해와 계산 과정의 단계별 풀이를 보여주는 웹 기반 이러닝 콘텐츠를 설계 및 개발하는 것이다. 이를 위하여 먼저 수학교육용 소프트웨어에 관한 고찰을 하였으며 학교 수학에서 등장하는 문제해결의 과정을 규칙 재작성으로 처리함으로써 화이트박스 형태의 콘텐츠 제작에 관한 이론적 토대를 살펴보았다. 구체적으로 Mathematica의 패턴 매칭을 이용하여 미분과 적분 연산자를 구현하였고, 이를 벡터미적분에서 등장하는 매개변수화된 곡선에 대한 길이 구하기 문제에 적용함으로써 콘텐츠 개발의 예를 제시하였다. 튜토리얼 형태로 개발된 이러닝 콘텐츠는 단계별 풀이 과정이 나오는 실습하기 콘텐츠와 퀴즈 문제를 통하여 학습자의 과정을 진단해 주는 형성평가 모듈로 구성되었다. 끝으로 개발된 이러닝 콘텐츠의 특징과 이공계 대학생들의 수학에 관한 기초학력을 증진하는데 활용될 수 있는 장점을 살펴보았으며 향후 연구 방향을 제시하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1001-1006
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• 2003

This paper presents the pedestrian navigation algorithm and the error compensation filter. The pedestrian navigation system (PNS) consists of the MEMS inertial sensors, the fluxgate, and the small-size GPS receiver. PNS calculates the navigational information using the signal patterns of the accelerometers. And the navigational information is completed by integration of the patterns, the fluxgate, and the GPS information. In general, PNS can provide the better solution than the low-cost inertial navigation system.

• Journal of applied mathematics & informatics
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• 제8권1호
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• pp.165-180
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• 2001

This paper presents a new difference scheme for numerical solution of stiff system of ODE’s. The present study is mainly motivated to develop an absolutely stable numerical method with a high order of approximation. In this work a double implicit A-stable difference scheme with the sixth order of approximation is suggested. Another purpose of this study is to introduce automatic choice of the integration step size of the difference scheme which is derived from the proposed scheme and the one step scheme of the fourth order of approximation. The algorithm was tested by means of solving the Kreiss problem and a chemical kinetics problem. The behavior of the gas explosive mixture (H₂+ O₂) in a closed space with a mobile piston is considered in test problem 2. It is our conclusion that a hydrogen-operated engine will permit to decrease the emitted levels of hazardous atmospheric pollutants.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.55-60
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• 2004

This study is concerned to the perforation phenomena of the oblique dual-plate by projectile. Experiment and simulation related to that was carried out. the variables considered in this phenomena include the electrolytic zinc coated steel sheet and carbon steel rod. In the former, the confirmation and projectile velocity possible phenomena of real phenomena is done, the latter, the effect of parameter such as time-step and grid space length is analized by using the three-dimensional Lagrangian explicit time-integration finite element code, HEMP. this code use the eight node hexahedral elements and in this study, Von-Mises Criteria is used as the strength model, Mie-Gruneisen is as the Equation of State. the simulation was performed by contrast with the experiment. through the calibration of the parameter of lagrangian code, reasonable result was approached.