• 대한기계학회논문집
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• 제17권9호
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• pp.2304-2314
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• 1993

Natural convective flow and heat transfer in a two-dimensional square enclosure fitted with a horizontal partition are investigated numerically. The enclosure was composed of the lower hot and the upper cold horizontal walls and the adiabatic vertical walls, and a partition was situated perpendicularly at the one vertical insulated wall. The governing equations are solved by using the finite element method with Galerkin method. The computations were carried out with the variations of length, position and thermal conductivity of the partition, and Rayleigh number based on the temperature difference between two horizontal walls and the enclosure height with water(Pr=4.95). As the results, an oscillatory motion of natural convection is resulted in a sudden rise of overall heat transfer, but the increase of length of partition is significantly restrained the increase of Nusselt number. The maximum heat transfer was shown just before the transition of the direction of oscillating flow. An oscillatory motion of flow was perfectly shown the stability with the decrease of the length of partition and Rayleigh number. Also, the heat transfer was raised with the increase of the thermal conductivity in proportion to the increase of the length of partition. The stability and oscillation of flow are affected by the position of partition.

• 디자인학연구
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• 제13권
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• pp.139-150
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• 1996

본 연구는 국내 패션업계 중 가장 오래된 기업의 하나인 코오롱 모드의 BI와 그 아래있는 5개의 개별 브랜드 - 아더딕슨, 아르페지오, 맨스타, 쟈스트, 벨라, 등의 BI개발 작업을 통해서 급변하는 패션시장 상황과 소비자 성향에 부응하고자 기존의 이미지 틀 위에 새로운 이미지를 형성하는 리노베이션을 위한 BI를 연구하고자 한다. 이를 위해서 구체적인 연구방법은 각 브랜드의 특성과 컨셉이 기존 BI에 어떻게 충족되고 있는지를 분석하고 대상고객의 라이프 스타일과 전체 패션시장의 경향에 맞춰 기존 이미지의 강점을 계승하고 단점을 보완하는 방법으로 이루어졌다. 신규브랜드의 BI와는 달리 리노베이션을 위한 BI란 기존의 고객은 유지하면서 더욱 더 많은 고객을 유도하는 것이 목적이므로 급격한 변신은 피하는 것이 특징이다.

• 폴리머
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• 제27권3호
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• pp.201-209
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• 2003

나일론의 종류에 따른 분쇄형 탄소 섬유/나일론 복합재료의 직류 및 교류 전도도, 그리고 전자기파 차폐 효율을 조사하였다. 탄소 섬유의 함량이 약 7 vol%에서 전도도가 급격하게 증가하는 percolation 전이가 관찰되었다. 나일론 46을 기저 수지로 하였을 경우 더욱 높은 전기 전도도를 나타냈으며, 계면 결합제의 적용 여부에 따라 전도도의 차이가 발생하였다. 온도증가에 따라 전도도가 증가하는 negative temperature coefficient 현상을 나타냈으며, percolation 전후의 탄소 섬유 함량에서의 주파수에 따른 전도기구를 완화와 공진 현상으로 각각 달리 설명할 수 있었다. 회로망 분석기를 통하여 측정한 전자기파 차폐 효율은 전도도 및 탄소 섬유의 함량에 따라 증가하였으며, 높은 전도도 영역에서의 전자기파 차폐 효율은 반사에 의한 차폐가 지배적이었다.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2007년도 춘계학술대회 논문집
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• pp.131-136
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• 2007

According to the OECD Report, Korea passed the first threshold to an "aging society" in which the elderly aged over 65 make up at least 7 percent of the population in 2000, and in 2018, are due to pass the second to an "aged society" in which they make up at least 14 percent-just 18 years later. It took France (starting in 1864) 115 years to complete this transition. Even Japan, legendary for the rapidity of its aging, required 24 years. It means Korea has to prepare for the aging of its population within a very short time without mistakes. Meanwhile, in a 2005 survey of the elderly, 85.5% of them preferred aging in place to moving to elderly care facilities. That means housing planning for the elderly which provides them with independent living needs to be considered seriously. The digital technology integrated home may be one of the alternatives to support this idea. In order to find a way to user oriented digital homes for the elderly, this study identified the their needs on the physical features of the ideal home and the digital services necessary through digital life scenarios.

• Progress in Superconductivity
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• 제3권2호
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• pp.140-145
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• 2002

An enhancement of the c-axis differential conductance around the zero-bias voltage near the superconducting transition temperature $T_{c}$ has been observed in $Au/Bi_2$$Sr_2$$CaCu_2$$O_{8+x}$ junctions. We attribute such an enhancement to the Andreev reflection (AR) between the surface Cu-O bilayer with suppressed superconductivity and the next superconducting Cu-O bilayer. The continuous evolution of the differential conductance, from gap like depression to an AR-like peak structure, around the zero-bias voltage points to weakening of the barrier strength of the nonsuperconducting layer between adjacent Cu-O bilayers as temperature approaches $T_{c}$ from below. The peak structure disappeared just below the bulk $T_{c}$ value of underdoped Bi2212 single crystals, whereas it survived up to ~1 K above $T_{c}$ in Junctions prepared on slightly overdosed crystals. According to a recently proposed theoretical consideration, a wider temperature range of the AR a bone $T_{c}$ is expected in the underdoped regime when phase-incoherent preformed pairs emerge in the pseudogap state. Our result is in contradiction to the preformed pair scenario. scenario.o.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.381-386
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• 2006

Many different types of bleaching chemicals and processes have been globally used for deinked pulp. Besides chlorine-free bleaching chemicals, hydrogen peroxide, and sodium dithionite that could be used without restriction for almost all types of fibers, chlorine-containing chemicals such as chlorine dioxide and sodium hypochlorite have also used throughout the world. Even though hydrogen peroxide is commonly used in newsprint, it could not effectively increase brightness. Experimental evaluation on the possibility of using formamidine sulfinic acid (FAS), a reducing agent, for bleaching a wood-containing deinked pulp has been carried out in this study. The effect of bleaching efficiency for FAS on operational conditions and chemical concentrations compaired to hydrogen peroxide in one and two stages was studied. FAS bleaching showed higher brightness at high temperature and low consistency, and vice versa for peroxide one. Bleaching with sodium silicate and DTPA in FAS and peroxide stage showed better results than cases without them. Sodium silicate and chelant seemed minimize the influence of transition metal ions, including manganese and iron ions, which induce both bleaching agents to decompose. As a result, FAS as a reducing agent seems more effective than hydrogen peroxide for increasing brightness and reducing yellowness. FAS and FAS sequence seemed more efficient than the other two stages of bleaching sequences with regard to the best brightness level obtained. When bleaching was conducted with FAS, COD load was just about one-third compared to peroxide, and brightness stability of the bleached pulp appeared better than peroxide after UV light irradiation.

• Transactions on Electrical and Electronic Materials
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• 제11권4호
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• pp.174-177
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• 2010

We have developed an environment-friendly etching process, an alternative to the dichromic acid etching process, as a pretreatment of acrylonitrile-butadiene-styrene (ABS) plastic for electroless plating. In order to plate ABS plastic in an electroless way, there should be fine holes on the surface of the ABS plastic to enhance mechanically the adhesion strength between the plastic surface and the plate. To make these holes, the surface was coated uniformly with dispersed chemical foaming agents in a mixture of environmentally friendly dispersant and solvent by the methods of dipping or direct application. The solvent seeps into just below the surface and distributes the chemical foaming agents uniformly beneath the surface. After drying off the surface, the surface was heated at a temperature well below the glass transition temperature of ABS plastic. By pyrolysis, the chemical foaming agents made fine holes on the surface. In order to discover optimum conditions for the formation of fine holes, the mixing ratio of the solvent, the dispersant and the chemical foaming agent were controlled. After the etching process, the surface was plated with nickel. We tested the adhesion strength between the ABS plastic and nickel plate by the cross-cutting method. The surface morphologies of the ABS plastic before and after the etching process were observed by means of a scanning electron microscope.

• 한국자기학회지
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• 제20권6호
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• pp.212-215
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• 2010

비정질 Ga 박막은 벌크에 비해 높은 초전도 임계온도와 임계자기장 값을 보이나 그 특성은 불안정하여 상온에 한번 노출되면 그 초전도 특성을 잃어버리게 된다. 이 논문에서는 Ga/Al 두층 박막을 제작하여 이러한 비정질 Ga 박막의 불안정한 초전도 특성을 개선할 뿐만 아니라 기존의 스핀검출에 응용되고 있는 Al 박막을 대체할 수 있는 가능성을 연구하였다. 극초진공 분자빔박막 증착장비(UHV-MBE)를 사용하여 Ga/Al 두층 박막을 제작하고, 표면의 적절한 플라즈마 산화 처리에 의한 Ga/Al/$Al_2O_3$/Fe의 터널 접합구조를 제작하여 Ga/Al 박막의 초전도 특성을 측정하였다. 한편, Ga/Al 박막의 표면 특성은 Auger 전자 분광기를 이용하여 분석하였다.

• 한국실내디자인학회논문집
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• 제32호
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• pp.131-137
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• 2002

The development of fast information network connections and the information highway of todays society have made consumers to demand various services in interior design. The media influencing consumer behavior is with no doubt, the Internet. The exponential growth in Internet users in Korea is surprised to all other countries. At this time where new businesses and events on the Internet are developing successfully, the educational and cultural benefits to consumers, which is quite different from the time when consumers only depended on television and newspaper, are enabling consumer demand to grow together with the abundant floods of information. This implies that consumer choice is shifting from needs-based to wants-based products and services. In the past where only the necessities were mass-produced and there was a lack in goods in general, there just werent enough products or varieties for consumers to either compare or evaluate. Today, comparing and evaluating has become natural with the access to information, and consumers have teamed to choose interior products that fit their preferences. In other words, this means that consumers are now at a transition point where they are moving from the simple everyday needs of the past to wants of the present that allows them to form a standard for selecting products of their own preference.

• Asia pacific journal of information systems
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• 제10권4호
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• pp.133-152
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• 2000

Successful Electronic Commerce(EC) requires not only a transformation of the supply chain but a redesign of organizational processes as well. Just as the organizations in a supply chain must cooperate with each other to achieve a collective goal, so too do the departments and groups that comprise an organization depend on each other to achieve the organization's goals. A lack of coordination at either of these levels can result in poor performance and high coordination costs. In addition, changes in inter-organizational dependencies can affect the dependencies within the affected organizations. The lack of coordination across two levels results in a transition gap in transforming the inter-organizational design to the intro-organizational design in EC deployments. The purpose of this research is to develop a modeling method for coordination, managing the linkage between inter- and intra-organizations in EC deployments. The method was applied to the EC development project of a cable TV home-shopping company. The coordination approach enabled us to manage dependencies among the coordination elements and identify the effect of a change on other elements, which became the basis for effective EC deployments. We will discuss the method and compare it with other dependency management methods.