• 대한수학회논문집
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• 제26권1호
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• pp.125-133
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• 2011

A new kind of structure is introduced in an even dimensional differentiable Riemannian manifold and some basic properties of this structure is discussed. Also the existence of such structure is shown with an example.

• 대한조선학회 특별논문집
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• 대한조선학회 2015년도 특별논문집
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• pp.56-62
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• 2015

In ship structure, many parts are in contact with inner or outer fluid as stern, ballast and oil tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these tanks in contact with fluid are significantly affected by fluid coupling effect. Therefore it is important to exactly predict vibration characteristics of tank structure. In order to estimate the vibration characteristics, the fluid-structure interaction(FSI) problem should be solved precisely. But it is difficult to estimate exactly the magnitude of the fluid coupling effect because it has some problems such as a fluid-structure interaction, influence by the free surface, vibration modes of structural panels and depth of water. In this paper, with fluid coupling effect, the effect of structural constraint between panels on the vibration characteristics are investigated numerically and discussed.

• 대한의용생체공학회:의공학회지
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• 제19권5호
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• pp.519-530
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• 1998

본 논문에서는 하지 전단 환자의 보행 성능을 개선하고, 활동성을 증대시긴 목적으로 에너지 저장형 의족의 유연 용골 선계를 위한 기초 연구를 수행하였다. 문헌에서 얻을 수 있는 2차원 시상면에서의 정성걸음새와 인체측정 데이터를 분석하여, 의족의 유연 용골 기초 구조 모델을 제시하였다. 기초 구조 모델은 단순한 빔과 선혈 회전 스프링 ·댐퍼로 구성되었다. 고강도 경량 소재를 의족의 유연 용골 기초 구조에 적용하기 위해 탄소섬유 강화 복합재료를 용골의 기초 구조 소재로 선정하였다. 빔의 형상 변화에 따른 복원변형에너지를 유한요소해석에 의해 계산해내고, 빔형상 변화가 설계변수가 될 수 있음을 제시하였다. 복원변형에너지를 많이 저장할 수 있는 유연 용골 구조의 설계를 위해, 직교배열표를 이용한 조지전 시뮬레이션 계획을 세우고, 유한요소 프로그램인 ABAQUS를 이용하여 계획에 따른 유한요소해석을 수행하고, 분산활석을 통해 효과적인 에너지 저장형 의족의 유연 용골 구조를 얻어냈다. 유연 용골 구조를 이용한 의족걸음새의 동적 시뮬레이션 모델을 완성하고, 한 보행 사이클 동안의 동적 해석을 수행하였다. 그리하여 의족 시스템 개발을 위한 효과적 설계 과정이 제시되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.255-258
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• 2001

This paper proposes a new structure of a fiber-optic illuminator using high Lux RGB LEDs. A simulation program, LightTools, is used for the verification of the model. An LED mounting holder containing 74 RGB LEDs is used as a basic part of its light collector. Since the light output level of current LED lamps is still far below that of conventional lamps, it is required to double the right output in order to replace a conventional illuminator with a halogen lamp. An additional cone-type reflector is installed hemispherically and the resulting structure comprises a basic collector unit. To further increase the output two collector units are connected together in series. As the result, the light output increases nearly 70% with compared to a collector with a basic structure. The system efficiency can be increased more than 8 times with compared to conventional one.

• Applied Microscopy
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• 제41권1호
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• pp.75-79
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• 2011

For quantitative analysis of nano-crystal structure, we reported the accuracy improvement method of lattice parameters measured from electron diffraction. For calculation of Au lattice parameters used as a standard crystal structure, it was considered two different acquisition methods (detector and enegy-filter) and three different calculation methods (conventional, least-square and regression fit). As a result, the measurement reliability could be enhanced by using CCD camera which gives higher performance, while energy-filtering did not affect the improvement the camera constant accuracy. Also, the accuracy of lattice parameters could be improved up to $10^{-4}$ order by regression fitting with correction formula. Finally, it is expected that the combination of regression fitting and intensity extraction from energy-filtered precession electron diffraction gives a solution of quantitative structure analysis for unknown nano-crystals.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2717-2722
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• 2009

The use of the classification and regression tree (CART) methodology was studied in a quantitative structure-activity relationship (QSAR) context on a data set consisting of the binding affinities of 39 imidazobenzodiazepines for the α1 benzodiazepine receptor. The 3-D structures of these compounds were optimized using HyperChem software with semiempirical AM1 optimization method. After optimization a set of 1481 zero-to three-dimentional descriptors was calculated for each molecule in the data set. The response (dependent variable) in the tree model consisted of the binding affinities of drugs. Three descriptors (two topological and one 3D-Morse descriptors) were applied in the final tree structure to describe the binding affinities. The mean relative error percent for the data set is 3.20%, compared with a previous model with mean relative error percent of 6.63%. To evaluate the predictive power of CART cross validation method was also performed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.43-46
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• 2004

We demonstrated efficient white light emitting OLEDs with a single emissive layer structure, which was blue-emitting 1,4-bis[2,2-diphenylvinyl]biphenyl (DPVBi) doped with blue luminescent amino-substituted distyrylarylene amine (DSA-amine) and red luminescent [2,6-bis[2-[5-(dibutylamino) phenyl]vinyl]-4H -pyran-4-ylidene]propanedinitrile (DADB). Through the optimization of the device structure, the white light emission with full visible spectral range was obtained. Its CIE color coordinates was (0.32,0.42) at 10 $mA/cm^2$ and the external quantum efficiency, the luminance efficiency and the luminance yield were 3.7 %, 3.3 lm/W and 9.0 cd/A, respectively.

• 대한간호학회지
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• 제27권4호
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• pp.892-900
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• 1997

The purpose of this study was to use phenomenological perspectives to identify the meaning and structure of the observational experience of labor and delivery by student nurses in the clinical setting. The participants were 115 junior and senior students from Christian College of Nursing in Kwang Ju. The students were asked to write about their observational experience in the delivery room. Colaizzi's method was used for phenomenological analysis. The investigator analysed the data to identify and categorize themes and basic structural elements. Twelve themes and eight basic structure were identified. The process of the observational experience in labor and delivery has three proposed phases : anticipatory, observational and post-observational. In the anticipatory phase, nursing students were related only to the event of anticipated labor and delivery of clients. Structure 1, feeling of expectation and fear, was identified. In the observational phase, students were related to the labor and delivery situation, a woman delivered and a newborn. Structure 2, shock and suffering, was identified in relation to the labor and delivery situation. Structure 3, need for caring and satisfaction, was identified in relation to the woman delivered. Structure 4, feeling of mystery and joy, was identified in relation to the newborn. In the post-observational phase, relations between students and the life of a human being, students and self in the future, students and their mothers and students and women and God appeared. And in these relations 〈structure 5, valuable〉, 〈structure 6, feeling of expectation and fear〉, 〈structure 7, love and appreciation〉 and 〈structure 8, greatness〉 were identified.

• 건축역사연구
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• 제1권2호
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• pp.172-182
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• 1992

The binary classification, Yin & Yang, can be shown in our culture. Yin & Yang thinking reveals the Up/Down (Principal/Subordinate) relation in space, and Before/After relation in time, and it shows the sequence of Contrast${\to}$Reconciliation & Unification${\to}$Contrast. For example, a follower is Yin against King, while Yang as a father against his son in our trational cognitive structure. With Left/Right, Front/Rear, and Upper/Lower, In/Out division is a basic body-space term to grasp the space position. In the traditional Korean house, when we go out from the deepest 'In', Anbang to Daechung, we may call Anbang 'In' and Daechung 'Out'. When from Daechung to Anmadang reversely, we call Daechung 'In' and Anmadang 'Out'. Namely, Daechung is both 'In' and 'Out'. This is a fallacy logic in view of western basic conception. 'The In/Out Structure, system of a series of inner spaces, is defined as a transformation of cognitive structure of Yin & Yang thinking to the Korean architectural space. The space structure is one of the important deep structure in Korean society.' The concept of the space structure, apperred in east Asia, can make humane space, for it is not a physical 'type' of typepology but related to cognitive structure of human thinking, The structure is applicable to space design in modern society, for the cognitive structure exists in living culture by transformation.

• Journal of Magnetics
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• 제3권1호
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• pp.21-30
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• 1998

An artificially modulated magnetic Co/Pd multilayer is one of the promising candidates for high density magneto-optic (MO) recording media, due to large Kerr rotation angle in the wavelength of a blue laser beam. however, since multilayer structure, as well as amorphous structure, is a non-equilibrium state in terms of free energy and MO recording is a kind of thermal recording which is conducted aound Curie temperature (Tc) of the recording media, when the multilayer is used for the MO recording media, changes in the multilayer structure are occurred as the amorphous structure do. Therefore, the assessment of the structural stability in the Co/Pd multilayer is crucially important both for basic research and applications. As the parameter of the structural stability in this research, modulation amplitude and particle size of the Co/Pd multilayer are measured in terms of Ar sputtering pressure and heat treatment temperature. From the results of the research, we find out that the magnetic exchange energy in the structural changes of a magnetic multilayer structure and suggest the operating temperature range for MO recording in the Co/Pd multilayer for the basic research and applications, respectively.