• 한국초전도ㆍ저온공학회논문지
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• 제8권2호
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• pp.33-36
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• 2006

Multi-stacked HTS wires are needed to conduct large current in the power application. In this paper, magnetization losses of the multi-stacked YBCO wire and the BSCCO wire have been measured and compared. 4 types of YBCO wires and BSCCO wires, that is, single, 2-stacked, 3-stacked and 4-stacked, have been tested. HTS multi-stacked wires were fabricated using face-to-face type stacking method. Measurements of magnetization loss were performed under various angles of external magnetic field to consider the anisotropic characteristics of HTS wires. The ratios of the magnetization loss by multiple stacking of superconducting wires were presented. Measurements results show that loss reduction ratios have three distinct regions due to the magnitude of external magnetic field, the material of HTS wire and number of stacks.

• Korean Journal of Mathematics
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• 제4권1호
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• pp.17-30
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• 1996

In ergodic theory cutting and stacking constructions have been used to obtain a variety of important examples of transformations on the unit interval. We examine the example constructed by J. von Neumann and Kakutani and then apply the method used in the construction of Chacon's transformation to make examples that are weakly mixing but not mixing.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 춘계학술대회 논문집
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• pp.387-388
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• 2010

• 한국실내디자인학회논문집
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• 제13권3호
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• pp.145-152
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• 2004

The European architects including MVRDV, Rem Koolhaas, Van Berkel, and Zaha Hadid tend to use the their own design strategy based on the objective data. This Architectural design method leads to make new paradigm of contemporary architecture. For the purpose of the understanding a part of new architecture paradigm I will analyze the case of Villa VPRO designed by MVRDV. At the result, I can draw the following conclusions. First, through collecting and analyzing data, drawing design concept and planning the space program, they decided on the design strategies of Villa VPRO. They designed the space volume having 42.4m$\times$42.4m floors and infiltrated environmental elements to solve the problems about deep space. Second, Villa VPRO was constructed by 'creative space-making system: a series of floors much like a geological formation, the continuous floors interconnected by spatial means, the precision bombardments of snake-like holes, open elevations, the stacking spaces. Third, Villa VPRO produced the spectacle space effect the various formation of continuous floors make a lot of difference space types in this building. Also they lead to move naturally and give event space. A numbers of holes and openness make it possible to provide friendly environment with combining light and air with views of the surrounding and transparency. And using the method of stacking many types of space make the differences in height.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.420-423
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• 2008

This present work is to find optimum design of a NACA65 axial fan blade with weighted average surrogate model. The numerical analysis by Reynolds-average Navier-Stokes equations with shear stress turbulence(SST) is discretized by finite volume approximations and solved on hexahedral grids for flow analysis. The blade aerodynamic shape is modified by six design variables for the optimization. The blade profile as well as stacking line is modified to enhance blade total efficiency. Six design variables, airfoil maximum camber, maximum camber location, leading edge radius, trailing edge radius, lean angle at 50% span and lean angle at 100% span, are selected for blade profile to enhance the total efficiency. The PBA model which is basically weighted average of the basis surrogates is used to find the optimal design in the design space from the constructed response surface model for the objective function. By the optimization, the total efficiency is increased by 1.4%.

• 한국산학기술학회논문지
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• 제3권2호
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• pp.126-130
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• 2002

본 논문은 쾌속제작법을 이용한 임의형상을 가공하는 새로운 방법의 개념을 소개하고 있다. 본 시스템은 레이저 절단, 이송. 적층, 소결의 단계를 통하여 세라믹재료로 된 임의형상을 가공할 수 있다. 시스템을 구성하는 주요장비로는 레이저 발생장치, X-Y테이블, 이송시스템, 그리고 전기로 등이 있다. 이 시스템을 사용하면 표면의 거칠기가 매끄러운 형상을 상대적으로 짧은 시간에 제작할 수 있는 장점이 있다. 또, 2차 공정을 거치지 않고, 바로 물체를 제작할 수 있어 효율성이 높다고 할 수 있다. 제작된 모형은 바로 조립되어 사용될 수 있기 때문에 응용분야가 다양하다.

• Current Photovoltaic Research
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• 제9권4호
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• pp.137-144
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• 2021

In this study, the microstructure of the CVD-fabricated Cu(In,Ga)Se₂ (CIGSe) absorber layer by simulating the stacking sequence used in a co-evaporation method, and changes solar cell performance were investigated. The absorber layer prepared by stacking CuSe and (In,Ga)Se between InSe is separated into Ga-free CuInSe₂ and Ga-rich CIGSe, and transformed to CIGSe by selenization heat treatment with slight improvement in the the solar cell efficiency. However, in CVD, since the supply of liquid Cu-Se is not as active as in the co-evaporation method, the nanoocrystalline layer containing a large amount of Ga remained independently in the absorption layer, which acted as a cause of the loss of J_SC and FF. Therefore, by using a precursor structure in which CuGa is sputter-deposited on a single layer of InSe deposited by CVD, performance parameters of V_OC, J_SC, and FF could be greatly improved.

• 한국식품저장유통학회지
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• 제20권3호
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• pp.289-295
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• 2013

차압예냉시스템을 설계하기 위해서는 송풍저항을 정확하게 예측해야 하며, 송풍저항은 청과물의 적재방법에 따라 크게 달라진다. 본 연구는 차압예냉시스템에서 송풍량에 따른 송풍저항식과 상자의 적재방법별로 송풍저항을 측정할 수 있는 모델을 개발하기 위하여 수행되었다. 공을 퇴적한 모형상자에서의 송풍저항은 빈 상자에서의 송풍저항과 공 퇴적층만의 송풍저항을 합한 값보다 1.5배 정도 높게 나타났다. 또한, 적재상자에서의 송풍저항은 통기폭 방향 적재상자수의 증가에 따라 지수적으로 증가하였으나, 적재길이와 적재높이의 영향은 거의 받지 않았다. 상자를 2열로 적재하는 차압예냉시스템에서 송풍저항은 1개 상자에서의 송풍저항을 기초로 예측이 가능하였으며, 예측모델을 제시하였다.

• 한국세라믹학회지
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• 제29권9호
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• pp.695-704
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• 1992

In (Pb, La)(Zr, Ti)O3 ceramic system, the functionally gradient material (FGM) was developed, and its processing and properties were investigated. The FGMs were successfully prepared through doctor blade method with acrylic binder system as well as mold stacking press method. The ultrasonic treatment was very effective for particle dispersion in slurry, and it lead to form clack-free green films. The strain-voltage characteristics of the FGM system was significantly improved which fabricated between a high piezoelectric-low dielectric and a low piezoelectric-high dielectric composition layer.

• 한국진공학회지
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• 제5권3호
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• pp.258-262
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• 1996

d.c.magnetron sputtering 방법으로 제작된 Fe/[NiFe/Cu] 다층박막을 Fe 기저층의 두께, 적층횟수 및 열처리 온도 변화에 따라 자기저항비가 계면 거칠기 및 우선 배향에 미치는 영향에 대하여 조사하였다. Fe 기저층의 두께가 증가함에 따라 (200) 우선 배향의 세기라 증가하였으며, 자기저항비는 Fe70$\AA$의 두께어서 최대값 4.7%를 보이며 이때 자장감응도도 최대를 나타낸다. Fe 기저층의 두께를 70$\AA$ 으로 고정시키고 적층횟수를 변화시켰을 때 40층에서 최대값 5.3%를 보였다. 열처리 온도에 따른 자기저항비는 $300^{\circ}C$이하에서는 커다란 변화가 없으며, $300^{\circ}C$이상에서는 크게 감소하였는데, 이는 Cu의 확산에 의한 상자성 혼합층의 증가와 반강자성석으로 결함된 자성층간의 배열의 변화가 그 원인이다.