• 방송공학회논문지
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• 제9권1호
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• pp.43-53
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• 2004

본 논문에서는 에지를 고려한 순차주사화(EDI: edge dependent interpolation)와 전역 움직임 보상(GMC: globa1 motion compensation)을 결합한 효율적이면서도 안정적인 순차주사화 알고리즘을 제안한다. 일반적으로 에지를 고려한 순차주사화 알고리즘을 사용하면 한 장의 필드를 이용한 다른 순차주사화 알고리즘들을 사용했을 때보다 시각적으로 우수한 결과를 얻을 수 있다. 그러나 한 장의 필드에 담긴 영상 정보에는 한계가 있기 때문에, 한 장의 필드를 이용한 방법을 통해서는 원본 필드로부터 고화질의 순차 주사 영상을 얻을 수 없다. 이에 반해 움직임 정보를 이용한 순차주사화 방법은 공간 영역뿐 아니라 시간 영역의 정보를 사용하므로 한 장의 필드를 이용할 때 보다 더욱 정확하게 원 프레임을 복원해 내지만, 움직임 추정의 정확도에 따라 결과가 크게 좌우되는 단점이 있다. 따라서 제안된 알고리즘에서는 EDI와 GMC를 함께 사용한다. 또한 최상의 결과를 얻기 위해 GMC의 오류를 검출하는 적응적 문턱 알고리즘을 제안한다. 제안된 알고리즘을 사용하면 기존 방법들에 비해 수치상으로도 시각적으로도 뛰어난 결과가 나타나는 것을 실험을 통해 확인할 수 있다.

• 한국경영과학회지
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• 제27권1호
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• pp.19-32
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• 2002

This paper examines the effect of the producer-supplier quality contract parameters and the magnitude of the quality related variables on the quality of the final products. Our analysis focuses on the parties' equilibrium behavior In a quality game environment where the supplier should choose among the two production technologies, one requiring high cost but producing high quality Parts and the other requiring low cost but producing low quality parts and where the producer should decide whether to do the inspection of the parts. The game framework is employed to depict the potential conflicts existing between the Producer and the supplier because the Producer can not observe the supplier's choice and each party wants the other to bear the cost of producing high quality products. In our model, we specifically consider the competitive situation where the producer competes with a firm producing the same product. We employ the market share attraction model to Incorporate the competitive situation and completely characterize the equilibrium by using the Nash equilibrium concept for the game solution. Our results show that the equilibrium depends on the contract terms and the magnitude of the quality related variables. Compared to the non-competitive situation, the probability of producer's Inspection and the probability of supplier's choosing the high quality technology increases in a competitive situation. This is true even when the competitor's quality is lower than the producer's lowest. As a result, the quality of the final product increases In a competitive situation. And as the failure cost borne by the supplier increases, the probability of choosing the high quality technology Increases and the probability of inspection decreases. The net effect of this results in the decrease of the final product quality.

• Restorative Dentistry and Endodontics
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• 제26권4호
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• pp.316-325
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• 2001

The purpose of this study was to evaluate the effect of adhesive curing timing on the direction of polymerization shrinkage of light-curing composite resin. In this study, the curing times of adhesive and composite resin were measured by differential scanning calorimeter(DSC). 28 extracted human molars were embedded in clear resin and box-type cavities were prepared. Based on DSC data, the experimental teeth were divided into 4 groups. Group 1: no bond; Group 2: late curing; Group 3: Intermediate curing; Group 4: Early curing. After treating with adhesive, the buccal cavities were filled with Z-100 hybrid composite resin and the lingual ones were filled with AEliteflo flowable composite resin. The depressions at the surface were measured by surface profilometer, then the specimens were embedded in clear resin and sectioned. Impressions were obtained and used to get epoxy resin replicas. The epoxy replicas were gold-coated and observed under SEM. Average Maximum Gap(AMG), Gap Proportion(GP), Average Marginal Index(AMI) were used to compare the shrinkage gap of each group. The results were statistically analyzed using the Kruskal-Wallis One Way ANOVA, Student-Newman-Keuls method. The results of this study were as follows. 1. Average Maximum Gap, Gap Proportion, Average Marginal Index and depression at the surface or Z-100 hybride composite resin were smaller than those of AEliteflo flowable composite resin(P<0.05). 2. When the bonding between composite resin and tooth structure was strong, the shrinkage gap was small, and depression at the surface was deep(P<0.05). 3. In the well-bonded group, light-curing composite resin shrank toward bonded cavity wall, not toward light source. The result suggested that the direction of polymerization shrinkage was affected by the quality of bonding in the dentin-resin interface. The strong was the bonding between composite resin and tooth structure, the smaller was the gap and the deeper was the depression at the surface. Then the flow to compensate the polymerization shrinkage proceeded from surface to bonded cavity wall.

• 대한전자공학회논문지SP
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• 제46권6호
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• pp.68-77
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• 2009

본 논문에서는 저해상도 유추 보간법(interpolation algorithm derived from low resolution: ILR)을 이용한 공간적 디인터레이싱 기법을 제안한다. 일반적인 에지 기반 디인터레이싱 방법들은 화소 단위의 상관도를 이용하기 때문에 잡음과 밝기의 변화에 민감하다는 단점이 있다. 또 보간의 성능을 좌우하는 정확한 에지 방향을 판단함에 있어서 만족스럽지 못한 성능을 보인다. 이러한 한계를 극복하기 위해 본 논문에서는 먼저 보간 하고자 하는 픽셀 주위의 저해상도 블록의 특성을 먼저 탐구하고 이를 고해상도 블록에 적용함으로써 missing pixel 을 보간 하는 방법을 제안한다. 실험결과 제안하는 방법은 기존의 화소 단위의 에지 기반 디인터레이싱 방법보다 PSNR로 대표되는 객관적 성능과 주관적 화질 측면에서 우수한 결과를 나타내는 것을 볼 수 있었다.

• 한국전자파학회논문지
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• 제24권9호
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• pp.873-882
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• 2013

13.56 MHz 무선 에너지 전송 시스템의 효율적인 전자파 장해(EMI) 측정 및 분석 방법을 제안한다. 두 루프 안테나가 자유 공간과 PEC면 위에 있는 두 가지 경우에 대하여 영상법과 쌍대성을 이용하여 자계 결합 시스템의 등가회로 모델링 분석을 통하여 각 루프에 흐르는 전류 및 발생하는 전자장을 수식적으로 표현한다. 여기서 완전 도체(Perfect Electric Conductor: PEC)는 완전 도체의 무한한 평면의 형태를 가지며, 이후에는 PEC면이라고 지칭한다. 원점에서 부터 관측 지점까지의 거리보다 충분히 가까운 지점에서의 최대 전자장의 크기를 이용하여 원점에서 충분히 떨어진 지점의 최대 전자장의 크기를 이론적으로 유추할 수 있다. 근거리에서의 자기장의 크기로 이론적으로 유추한 10 m 떨어진 위치에서의 최대 전자장의 크기와 상용 수치 해석 툴을 이용하여 구한 10 m 떨어진 위치의 최대 전자장의 크기를 비교, 분석하였다. 또한, 이론적으로 구한 최대 자기장의 크기를 바탕으로 방사성 장해 허용 기준을 만족하는 최대 허용 전력의 크기도 쉽게 구할 수 있다.

• Coupled systems mechanics
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• 제7권6호
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• pp.649-668
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• 2018

In this paper, we present a numerical model for fluid-structure interaction between structure built of porous media and acoustic fluid, which provides both pore pressure inside porous media and hydrodynamic pressures and hydrodynamic forces exerted on the upstream face of the structure in an unified manner and simplifies fluid-structure interaction problems. The first original feature of the proposed model concerns the structure built of saturated porous medium whose response is obtained with coupled discrete beam lattice model, which is based on Voronoi cell representation with cohesive links as linear elastic Timoshenko beam finite elements. The motion of the pore fluid is governed by Darcy's law, and the coupling between the solid phase and the pore fluid is introduced in the model through Biot's porous media theory. The pore pressure field is discretized with CST (Constant Strain Triangle) finite elements, which coincide with Delaunay triangles. By exploiting Hammer quadrature rule for numerical integration on CST elements, and duality property between Voronoi diagram and Delaunay triangulation, the numerical implementation of the coupling results with an additional pore pressure degree of freedom placed at each node of a Timoshenko beam finite element. The second original point of the model concerns the motion of the outside fluid which is modeled with mixed displacement/pressure based formulation. The chosen finite element representations of the structure response and the outside fluid motion ensures for the structure and fluid finite elements to be connected directly at the common nodes at the fluid-structure interface, because they share both the displacement and the pressure degrees of freedom. Numerical simulations presented in this paper show an excellent agreement between the numerically obtained results and the analytical solutions.

• 가족자원경영과 정책
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• 제16권2호
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• pp.187-210
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• 2012

Pumasi and Cooperative Child Care Sharing have had positive results among participants and show possibilities of spreading out to the community in general. However, performance was not proved where it is clarified, and the experience of 23 local Healthy Family Support Centers have that ran the demonstration project were unable to be collected. It is the point of time when the initial backing up is important but the centers do not have the systematic support. Therefore, this research presents an effective management plan through qualitative research involving Pumasi participants and person in charge. The operation strategies by the stage of the project were as follows: First, in the beginning stage, the person in charge establishes the target and vision of the project. Second, when comprising the Pumasi team, it was necessary to consider their characteristics according to the team organization subjects. Third, it is necessary to extend the turn-off time and provide many programs so that the various populations can participate. Fourth, in the advertising step, word of mouth and individual contact needs to be utilized. Fifth, in a medium or small city or an urban-rural complex area, the person in charge should support the participants' Pumasi activities. Sixth, various programs such as a passive and active parent education program and Pumasi education program for the leader needs to be provided for the activation of Pumasi activities. Lastly, a cooperative child care sharing location needs to be constructed by the duality system of the base space and outer space. In this location, the inside play space for the children is essential.

• 복식문화연구
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• 제5권3호
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• pp.1-25
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• 1997

The consumers, who are characterized by gathering a wide scope of information and by putting into action immediately, have come to the new group searching for emotion and have played a leading role of market. The characgeristics of consumers are the fact that they have followed the street fashion with no-concept, independent of the trends which the brand has provide for consumers. Therefore it leads to a big gap between the fashion information for enterprises and market formation for consumer class. The principal purpose of this paper is to get closer the distance between the information which is used in merchandise plan and real market for consumers, and to suggest the new direction of information management system in order to enhance the hit rate of merchandise plan. The results are as follows : (1) It is shown the enterprises should divide the information data between fashion information and market information, and understand the mutual relationship of them, and regard the statistical data related on the change of sensitivity and desire in market specialized in attributes of street fashion as the emotional expression\`s view, and manage them by the feedback style. (2) It is shown that enterprises should fully understand the fashion factors in the line of fashion stream with the independence of theme in order to plan the merchandise effectively for market which are specialized in the duality that it has both conservation and innovation at the same time, and detect their change. (3) It is shown that in order to predict exactly, enterprises should reflect the statistical data and the emotional factors in planning the merchandise, bring up the systematic organization, expert system. (4) It is also shown that enterprises should make an effort to pursuit the discriminated brand through the feedback management in which the consumer\`s lasting desires are reflected.

• 한국조명전기설비학회지:조명전기설비
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• 제1권1호
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• pp.75-82
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• 1987

종래, 위상제어의 전력전자 회로는 전원에서 고주파분이 많이 포함되고 역율을 저하시키는 원인이 되었다. 그러므로, 본 연구에서는 이러한 영향을 개선시키기 위하여 Optimal PWM 방식을 제시하였다. Optimal PWM 콘버어터는 전원에서 실효 고주파분을 최소화하는 것이며, Optimal PWM 인버어터와 쌍대성이 있음을 알 수 있었다. Optimal PWM 콘버어터의 전류패턴은 Optimal PWM 인버어터의 전압패턴과 같은 스위칭패턴과 제어방법을 얻을 수 있었다. 이러한 PWM방식을 실현하기 위하여 고속 스위칭소자가 필요하게 되었다. 이전에는 강제 전류회로인 싸이리스터가 사용되었으나, 최근에 와서는 전류용 TR 또는 GTO 소자 등을 사용함으로써 이와같은 PWM 특성을 쉽게 실현할 수 있었다. 본 연구에서의 전원에서 실효 고주파 전류를 최소화하기 위한 제어방법, 회로 및 결과를 제시하였다.

• 한국수자원학회논문집
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• 제37권12호
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• pp.1009-1018
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• 2004

하천을 따라 분포된 비점 오염원을 하천 수질모형의 매개변수들과 동시에 추정하는 체계적인 방법을 제안하였다. 수립된 방법을 QUAL2E 모형과 함께 충주댐 하류의 남한강 구간에 적용하여 모형의 반응계수와 비점 오염 부하량에 대한 최적 추정을 수행하였다. 민감도 분석 결과로부터 선정된 반응계수들에 대한 초기 추정 결과에 따르면 하천 시스템에 대한 질량수지가 만족되기 위해서는 질소와 인의 비점 오염 부하량의 입력이 필요한 것으로 나타났다. 이에 따라 총질소와 총인에 대한 비점 오염 부하를 포함하여 확장된 추정 문제의 해로써 비점 오염 부하량을 추정하였다. 비점 오염 부하량과 동시에 추정된 반응계수들과 비점 오염원을 고려하지 않고 추정된 반응계수의 비친 결과, 그 자체에 대한 추정을 위해서 뿐만 아니라 수질모형의 적절한 보정을 위하여 비점 오염 부하량이 최적 추정 과정에 포함될 필요가 있음을 알 수 있었다. 하천수질 의형에 대한 최적추정 방법의 적용성을 민감도계수 행렬 구조의 관점에서 논하였다.