• 한국해안·해양공학회논문집
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• 제24권4호
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• pp.235-246
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• 2012

연안방재계획 수립을 위한 기초자료 생성의 일환으로 태풍에 의한 해일 범람모의를 수행하였다. 통상적인 침수-노출 처리가 불가한 직립안벽을 갖는 항만역의 특징이 반영되도록 가상의 내부제방 개념을 도입하여 해석하였다. 목포항에 대한 실제해역 적용에 앞서 단순해역에서 다수의 적용성 평가를 통해 내부제방의 폭은 1 m가 적정한 것으로 평가되었다. 해일범람으로 인한 침수면적과 침수심 산정에 민감하게 작용하는 육역의 침수-노출 처리기법에서의 최소침수심은 격자에 의존적이나 10 m 내외의 유한요소 상세격자에서는 0.01 m가 적정한 것으로 판단된다. 기존 태풍경로에 준거한 100년 빈도급 중심기압과 최대풍속을 가지며 비대칭 경도풍과 파랑효과가 고려된 가상태풍의 내습에 따른 목포해역의 침수예상역이 모의되었다. 침수면적은 기존 연구결과와 유사성을 나타내지만 항만권역 일부에서 확대 가능성이 있는 것으로 평가된다.

• 한국소음진동공학회논문집
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• 제15권8호
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• pp.891-896
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• 2005

On the basis of theoretical studies on the effect of the cylinders attached to semi-infinite screens, the tangential sound power-transport parallel to the surface of the attached cylinder is minimized by means of a secondary sound field, which is generated from a part of the attached cylinder. The numerical study shows the possibility of deflecting the incident sound by minimizing the sound field of the upper sections. The acoustical shadow region was more pronounced in both near- and far-field compared to the passive case with rigid surface, i.e. without active control. For a relatively wide frequency range it was possible to enhance shielding effects only with few secondary sources and error microphones. In this paper effects of control parameters on the actively controlled sound field near the top edge of noise barriers are studied. Results of numerical study and model measurements are shown and discussed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.332-337
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• 2005

In this study the sound field on the surface of the top edge of noise barriers is actively minimized to enhance the shielding effect without increasing the hight of the barrier. First the results of a numerical study are shown; the sound field reduction in the far field due to a cylindrical active headpiece attached to a semi-infinite screen and the related control parameters are investigated. The results of a model experiment in an anechoic chamber and optimal control parameters for noise control on the railway side are shown and discussed.

• Journal of Electrical Engineering and information Science
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• 제2권6호
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• pp.106-110
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• 1997

The binding energies of the ground state of both the heavy-hole and light-hole excitons in a GaAs(In\ulcornerGa\ulcornerAs) quantum well sandwiched between two semi-infinite Al\ulcornerGa\ulcornerAs(InP) layers are calculated as a function of well width in the presence of an arbitray magnetic field. A variational approach is followed using very simple trial wave function. The applied magnetic field is assumed to be parallel to the axis of growth and the binding energies are calculated for a finite value of the height of the potential barrier. The exciton binding energies for a given value of the magnetic field are found to be increased than their values in a zero magnetic field due to the compression of their wave functions within the well with the applied magnetic field.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.482-485
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• 2004

On the basis of theoretical studies on the effect of the cylinders attached to semi-infinite screens, the tangential sound power-transport parallel to the surface of the attached cylinder is minimized by means of a secondary sound field, which is generated from a part of the attached cylinder. The numerical study shows the possibility of deflecting the incident sound by minimizing the acoustic surface impedance of the upper sections. The acoustical shadow region was more pronounced in both near- and far-field compared to the passive case with rigid surface, i.e. without active control. For a relatively wide frequency range it was possible to enhance shielding effects only with few secondary sources and error microphones. In this paper effects of some control parameters on the actively controlled sound field near the top edge of noise barriers are studied. Results of numerical study and model measurements are shown and discussed.

• 한국표면공학회지
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• 제49권3호
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• pp.286-300
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• 2016

Pd-Ag alloy membranes have attracted a great deal of attention for their use in hydrogen purification and separation due to their high theoretical permeability, infinite selectivity and chemical compatibility with hydro-carbon containing gas streams. For commercial application, Pd-based membranes for hydrogen purification and separation need not only a high perm-selectivity but also a stable long-term durability. However, it has been difficult to fabricate thin, dense Pd-Ag alloy membranes on a porous stainless steel metal support with surface pores free and a stable diffusion barrier for preventing metallic diffusion from the porous stainless steel support. In this study, thin Pd-Ag alloy membranes were prepared by advanced Pd/Ag/Pd/Ag/Pd multi-layer sputter deposition on the modified porous stainless steel support using rough polishing/$ZrO_2$ powder filling and micro-polishing surface treatment, and following Ag up-filling heat treatment. Because the modified Pd-Ag alloy membranes using rough polishing/$ZrO_2$ powder filling method demonstrate high hydrogen permeability as well as diffusion barrier efficiency, it leads to the performance improvement in hydrogen perm-selectivity. Our membranes, therefore, are expected to be applicable to industrial fields for hydrogen purification and separation owing to enhanced functionality, durability and metal support/Pd alloy film integration.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.597-601
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• 2006

The advantages of solar energy are that it is renewable, infinite supplied and environmentally safe energy source. However, solar energy related products have the problems such as the limitation for installation, problems in maintenance and insufficient reliability which have been the barrier to consumers to satisfy the purchase need for solar heat related products. In this regard, in order to support the solar energy related companies the necessity for various technical information required for the commercialization of new products such as various performance test necessary for the certification of solar energy system, standardization for facilities and products, performance evaluation method and the measurement of performance is suggested. The purpose of this paper is to design the monitoring system for positive tests of system linked household hot water system using solar heat out of various solar energy systems, to establish an analysis and monitoring system for performance maintenance and operation technique, and to configure the centralized detection network by utilizing remote monitoring system. This research also aims at conducting monitoring for operation and performance evaluation in relation to database establishment and analytical evaluation and at describing the method of enhancing the reliability of solar energy system through the development of performance evaluation program.

• 한국전산구조공학회논문집
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• 제25권6호
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• pp.549-558
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• 2012

본 논문에서는 레벨셋 방법을 이용하여, 소음을 차단하기 위한 음향 구조물의 형상 최적설계를 수행하였다. 형상 최적설계의 목적은 특정한 각도와 각속도로 입사되는 입사파에 대해서 음향 투과율(acoustic transmittance)이 최소가 되도록 음향 결정의 형상(inclusion shape)을 결정하는 것이다. 음향 결정 구조에서는 음향이 흩어져 있는 결정 구조에 의해서 굴절되기 때문에 결정 모양을 조정함으로써, 음향 거동을 제어할 수 있다. 본 연구에서는 음향 구조물로 결정이 수평방향으로는 주기적으로 무한히 분포하고 수직방향으로는 유한한 층간 구조를 가지고 있는 소음 방어벽(Noise barrier)을 고려한다. 주기적 구조물을 고려하기 때문에 결정의 좌와 우에 Bloch 이론을 적용해 주기적 경계조건을 부과하였고, 소음 방어벽 위와 아래에는 임피던스 행렬(impedance matrix)를 이용하여, 무한 균질 영역과 소음 방어벽 사이의 음파 투과를 모사하였다. 결정의 위상과 형상변화를 묘사하기 위해서 레벨셋 방법(level set method)을 사용하였다. 레벨셋 방법에서는 초기 영역을 고정시킨 상태에서, 레벨셋으로 표현되는 임시적 경계(implicit moving boundary)를 변화시킴으로써 복잡한 형상을 다룰 수 있다. 몇몇 수치적 예제를 통해, 제시된 방법의 적용성을 검증하였다.

• The Korean Journal of Pain
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• 제29권2호
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• pp.86-95
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• 2016

Background: The present study was designed to examine the functional recovery following spinal cord injury (SCI) by adjusting the parameters of impact force and dwell-time using the Infinite Horizon (IH) impactor device. Methods: Sprague-Dawley rats (225-240 g) were divided into eight injury groups based on force of injury (Kdyn) and dwell time (seconds), indicated as Force-Dwell time: 150-4, 150-3, 150-2, 150-1, 150-0, 200-0, 90-2 and sham controls, respectively. Results: After T10 SCI, higher injury force produced greater spinal cord displacement (P < 0.05) and showed a significant correlation (r = 0.813) between the displacement and the force (P < 0.05). In neuropathic pain-like behavior, the percent of paw withdrawals scores in the hindpaw for the 150-4, 150-3, 150-2, 150-1 and the 200-0 injury groups were significantly lowered compared with sham controls (P < 0.05). The recovery of locomotion had a significant within-subjects effect of time (P < 0.05) and the 150-0 group had increased recovery compared to other groups (P < 0.05). In addition, the 200-0 and the 90-2 recovered significantly better than all the 150 kdyn impact groups that included a dwell-time (P < 0.05). In recovery of spontaneous bladder function, the 150-4 injury group took significantly longer recovery time whereas the 150-0 and the 90-2 groups had the shortest recovery times. Conclusions: The present study demonstrates SCI parameters optimize development of mechanical allodynia and other pathological outcomes.

• 복식문화연구
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• 제20권3호
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• pp.347-362
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• 2012

Formatively and artistically aspect, a hybrid can be said to be a phenomenon in which two mutually different genres are combined. Make-up is thought to be very important to arrange the foundation available for predicting and pursuing a flow and direction of future hybrid make-up based on this, by analyzing a flow centering on hybrid trend, which was shown previously. In terms of objectives of this study, the first, aim is to suggest a model for researching make-up by grasping the developmental process and the characteristics of hybrid art through considering an art theory of hybridity, shown in make-up. The second, aim is to design make-up by analyzing trends in make-up style after deconstructing the hybrid genre. The modern make-up design through genre-deconstruction characteristics beyond diverse plurality and genre could be known to be highlighted as aesthetic characteristic by a slight attempt as communication of open space, which connects culture and genre, which had failed to be recognized and was neglected. Empirical research has, produced a work by systematically arranging make-up design. This study, identifies two kind of barrier demolition, such as the class deconstruction and the temporal, spatial disorder centering on genre deconstruction of hybrid. There are infinite possibilities in developing make-up design in line with modern sensation through aesthetic element and symbolic significance through genre deconstruction. It was the expression mode in future make-up, to providing basic data, and to strengthening competitive edge of culture and art.