• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2006년도 춘계학술발표대회 논문집
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• pp.240-243
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• 2006

This thesis is a study on the exactitude of Simulation Tool by using illuminate formula. Lightscape looks like general 3d program, but is a lighting simulation program that set up the properties of materials and light-sources about the model. This thesis calculates illuminance by a formula and simulates a light simulation using Lightscape for two luminaires data in space of ideal environment. As then each value was compared. As a result we got an error under 1% on the whole.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.311-312
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• 2006

본 논문에서는 선로 전력조류제약을 고려한 경제급전(SCED : Security-Constrained economic dispatch)에 내점 선형계획법을 이용하여 최적해를 구하는 문제를 다룬다. 최적전력조류(Optimal Power Flow)식으로부터 선로의 유효전력만을 근사화하여 선로 전력조류 제약을 고려할 경제급전(SCED)의 식을 정식화한다. 선형계획법을 적용하여 최적해를 구하기 위해서 발전기출력과 유효전력, 부하, 손실과의 관계를 이용하여 경제급전의 식을 선형화 하는 알고리즘을 제시한다. 선형화 알고리즘은 목적함수로 계통 발전기의 총 연료비를 취하고 전력수급평형식으로 발전기출력증분에 대한 선로의 증분손실계수를 이용하며, 선로의 제약조건은 일반화발전 분배계수(GGDF : Generalized Generation Distribution Factor)를 이용하여 선형화한다. 최적화 기법으로서 내점법(Interior Point Method)을 적용하고자 하며 사례연구를 통하여 선형계획법 중 가장 많이 사용하는 심플렉스(Simplex)법과의 수렴특성을 비교하여 내점 법의 효용성을 확인하고자 한다.

• Journal of Biosystems Engineering
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• 제33권1호
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• pp.21-29
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• 2008

In this study, the thermal properties of peeled chestnuts were measured, and the mathematical prediction model of freezing time was also developed for various interior positions from center to rind (surface). The measured thermal properties were showed that heat conductivity is $0.43W/m^{\circ}C$, specific heat is $2.7206J/m^3^{\circ}C$, latent heat is $216.9{\times}10^6J/m^3$ and freezing point is $-2.8^{\circ}C$. The entire process about reaching to the freezing time of peeled chestnuts was analyzed with its each regular depth position using the finite difference method (FDM) based on computer simulation. In case of regular freezing temperature, it was showed an that surface (rind) position is more rapidly reached into the freezing point rather than the center position, and also reaching time to the freezing point is more fast at the lower freezing temperature. Comparison results between simulation and experiments showed linear relationship. In regularly varying condition for freezing temperature, this method would give an information to predict a freezing time of the interior points for peeled chestnuts and more similar agricultural products.

• 대한전기학회논문지:전력기술부문A
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• 제49권4호
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• pp.161-167
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• 2000

This paper presents a new methodology that can evaluate transfer capability of composite power systems from the adequacy point of view in power system planning stages. First of all, to evaluate practical load supplying capability, nonlinear optimization problems of maximum load supplying capability(MLSC) and economic load supplying capability(ELSC) are formulated and solved by nonlinear primal-dual interior point method. Here, physical constraints considered in the optimization problems are the limits of bus voltage, line overloading, and real & reactive power generation. Also, an evaluation method of transfer capability is presented based on margins calculated by the MLSC and ELSC. Especially, to evaluate transfer capability flexibly, simple indices such as expected MLSC, transfer capability margin, and power not supplied are respectively proposed by considering (N-1) line outage probability. Numerical results on IEEE RTS 24, IEEE 118, and IEEE 300 bus system show that the proposed algorithm is effective and useful for power system planning stages.

• 한국실내디자인학회논문집
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• 제38호
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• pp.75-82
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• 2003

The symmetry is general geometric design principal in contemporary architecture shape. But, Symmetry sometimes easily causes unreasonable design. In some reason, two of symmetric units in the apartment, one side of unit have very reasonable plan and arrangement but opposite side unit nay not. For example, if the kitchen on right unit had right-handed arrangement, the symmetrical other would have left-handed kitchen arrangement. In addition to this, if each house unit has the same plan but different direction, each unit has different usage or affects the residents' life pattern. Nevertheless, Architects use only one unit plan to design public housing development by using symmetric operator (mirror, proper rotation, inversion center) at their option. This study suggests that using group theory and mathematical matrix rather than designer's discretion can solve this symmetry problem clearly. And, this study analysis the merits and demerits between each symmetrical pair of unit plan shapes by using mathematical point group theory and matrix.

• Structural Engineering and Mechanics
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• 제67권2호
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• pp.185-206
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• 2018

This paper studies the non-axisymmetric 3D problem on the dynamics of the moving load acting in the interior of the hollow cylinder surrounded with elastic medium and this study is made by utilizing the exact equations of elastodynamics. It is assumed that in the interior of the cylinder the point located with respect to the cylinder axis moving forces act and the distribution of these forces is non-axisymmetric and is located within a certain central angle. The solution to the problem is based on employing the moving coordinate method, on the Fourier transform with respect to the spatial coordinate indicated by the distance of the point on the cylinder axis from the point at which the moving load acts, and on the Fourier series presentation of the Fourier transforms of the sought values. Numerical results on the critical moving velocity and on the distribution of the interface normal and shear stresses are presented and discussed. In particular, it is established that the non-axisymmetricity of the moving load can decrease significantly the values of the critical velocity.

• 경영과학
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• 제14권2호
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• pp.69-79
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• 1997

The computational speed of interior point method of linear programming depends on the speed of Cholesky factorization. If the coefficient matrix A has dense columns then the matrix A.THETA. $A^{T}$ becomes a dense matrix. This causes Cholesky factorization to be slow. We study an efficient implementation method of the dense column splitting among dense column resolving technique and analyze the relation between dense column splitting and order methods to improve the sparsity of Cholesky factoror.

• 한국실내디자인학회논문집
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• 제16호
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• pp.161-167
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• 1998

The Study to verify the relations between the store choice behavior and the interior environmental image. the point of view is that the image of store affects the behavior of customers when they choose the store for shopping. The method used for this study is library survey for constructing the store choice model and the field survey for veryfying the model. The store choice behavior of customers occurs according to the procedure : environment exposure-development of cognitive structure-image developing by the emotional response-attitude decision- purchasing. The image of a store is one of the very important elements in marketing stragy. The group which showed the affirmative response to the emvironmental design aspects also showed the high affirmative response to the store image. The group which showed consistent response to the image of store and the image of him/herself showed more affirmative response to the environmental design aspects. Good image to a store affects affirmative attitude of customers and it consequently the store choice behavior

• 한국실내디자인학회논문집
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• 제33호
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• pp.68-74
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• 2002

We human beings can only retain our normal consciousness and the power of thinking through the continuous transition of environment.. Lighting have been progressed inaccordance with these requirements and the demanding functions of our life style which played the important roll of bringing the stimulation we need with the new methods of performances, The advanced technology of today introduces the new method of combining the light, art and the Hi-technology into our artistic world bringing the new stimulation we have not experienced before. It is becoming the point of issue how to use these newly developed techniques and utilize, especially to those who are involved in the illumination environment and the world of Interior Design.

• 에너지공학
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• 제11권4호
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• pp.291-298
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• 2002

본 연구에서는 전력산업 구조개편 환경에서 최적조류계산에 의한 전력조류 및 한계계수를 해석할 수 있는 실용적인 방법론을 제시한다. 먼저, 유용한 한계계수의 산정을 위해 전압제약, 선로과부하 제약, 발전 출력 제약 등의 각종 계통제약이 고려된 연료비 및 송전손실 최소화의 비선형 최적화 문제가 정식화되고 비선형 주·쌍대 내점법에 의한 해법이 제시된다. 또한, 최적조류계산에 의해 계산된 감도에 기초하여 한계가격 및 한계송전손실의 산정방법이 제시된다. 특히, 경쟁적 전력시장에서 송전손실에 관한 가격을 반영하기 위해 한계손실계수의 해석법이 제안된다. 본 연구의 결과를 IEEE RTS 24모선에 적용하여 전력시장가격의 해석에 대한 그 유용성을 검증하였다.