• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.43-47
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• 1999

Instead of using KrF excimer lasers( ${\lambda}$ = 248 nm) in depositing oxide thin films, as in the most of the laboratories in Korea, we have used an ArF excimer laser( ${\lambda}$ = 197 nm) which has a shorter wavelength. By using a beam which has a shorter wavelength, we could obtain higher quality and smoother surface YBCO thin films. We fabricated YBCO thin films with the various substrate temperature conditions and analyzed the characteristics of these films. We also studied the charateristics of the films fabricated under the various conditions of the power of laser and the oxygen pressure. The characterization tools used in this work were a transport measurement setup, an XRD , and a SEM. We also fabricated STO/YBCO multilayers to use in SFQ devices fabrication. XRD patterns of the multilayers showed that the multilayer films were grown epitaxially.

• 한국정밀공학회지
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• 제13권8호
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• pp.52-59
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• 1996

Conventionally, grinding of stainless steel, aluminium ally, copper alloy, and titanum alloy are difficult to obtain the high quality finish, because they have the mechanical properties such as low hardness, high toughness which result in the loading of wheel and the poor surface finish. Inorder to perform the grinding operations for these sorts of materials easily, the discontinuous grinding wheel with multi-porous grooves has newly been developed. The multi-porous grooves were formed during wheel production. This discontinous grinding wheel increases the grinding performance. It is desirable to use the discontinuous grinding wheel when grinding materials wiht high efficiency and accuracy which is impossible by conventional wheels. In this paper, the constructing and manufacturing method of grinding wheel with multi-proous grooves are explained, and the grinding charateristics of discontinuous grinding wheel are also illustrate.

• 대한영양사협회학술지
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• 제8권3호
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• pp.318-327
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• 2002

The purposes of this study were to: a) examine charateristics of foodservice manaegment practices; b) investigate characteristics of recipients; c) analyze foodservice systems; and d) provide feedback for the efficient and effective foodservice management of welfare institutions for the homeless in Korea. A total of 27 sites was analyzed by questionnaire survey. Satatistical data analysis was completed using the SPSS package program for descriptive analysis. As results of site recipients' characteristics, 69% of total sites were males and 31% were female recipients. Average 60% of recipients were from 30 to 50 years old. Major diseases of recipients were high pressure, and obesity. According to the result of foodservice system analysis, the average meal cost per day was about 2,943 won and average food cost percentage was 29%. Average number of meals per day was about 600 meals. Mostl sites had one dietitian and 48.1% of sites had one cook as a full-time employee. In the part of procurement, dietitians were major chargers of sites for purchasing foods. Major purchasing method was the order and delivery contract. About a half of sites used cycle menu system and standardized recipies. Most of sites had recipients' survey systems for evaluating meal satisfaction. Dietitians at sites had problems on lack of cooking professionals and low meal cost budget for providing higher quality of foods to cure recipients. The results suggested that financial and systematical supports by the government would be very necessary to meet the goal of nutritional balanced meal services.

• 한국수자원학회논문집
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• 제41권10호
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• pp.1035-1044
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• 2008

하도내에서 발생하는 유출량 및 TOC 자료는 비선형성이 강한 자료임에 따라 홍수에 대한 재난대응과 수질의 상시감시를 위해서는 자료의 특성 분석과 예측에 관한 연구는 필수라 할 수 있다. 따라서 본 연구에서 유출량 및 TOC, TOC부하량 자료에 대한 웨이블렛 변환에 의해 최종분해된 최종파형분해단계의 근사성분과 상세성분을 이용하여 예측모형을 개발하였다. 그 결과 기존 인공신경망 모형에서 관찰되었던 시계반대 방향으로 전이되는 지속현상의 극복 가능성을 보여주었으며, 기존 인공신경망 모형에 비하여 예측의 정확도가 향상됨을 확인할 수 있었다. 이러한 연구결과는 향후 홍수에 대한 피해를 최소화하고 각종 수질사고에 적극적인 대응방안 수립이 가능할 것으로 기대된다.

• 지역연구
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• 제9권2호
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• pp.71-87
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• 1993

The purpose of this study is to analyze the restructuring processes of the locations of service industry whose demand has been decrease rapidly. The demand of movie theater has been change dramatically during the last three decades. the spatial distribution patterns of movie theaters have been changed according to the changes in the demand. In order to investigate the locational charateristics of movie theaters, in seoul we surveyed the consumer's behavior. We focused on the study to examine the relationships between the locations of movie theaters and transportation development. Especially, We look at the impacts of the development of subway networks on the locations of movie theaters in Seoul. The dvelopment of subway networks has played a very of movie theaters location. The hierarchicla structures of movie theaters have also chaged. Inspite of declining in the demand for movie theater, the number of first-run movie theaters has been increased continuously. The number of second-run movie theaters has been decreased dramatically. Some of them has been upgraded to first-run theater and some of them has been smallized. But, most of them have been closed. An the other hand the quality of movie theater facilities tends to be higher, while the sizes of movie theaters tends to be smallized.

• 한국결정성장학회지
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• 제14권3호
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• pp.90-94
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• 2004

The variation of electrical properties of (Ba,Sr)$TiO_3$ [BST] thin films for Metal-Insulator-Semiconductor (MIS) capacitors was investigated. BST thin films were deposited on p-Si(100) substrates by the RF magnetron sputtering with temperature range of 500~$600^{\circ}C$. The dielectric properties of MIS capacitors consisting of AUBST/$SiO_2$/Si sandwich structure were measured for various conditions. We examined the characteristics of MIS capacitor with various oxygen pressure, substrate temperature and (Ba+Sr)/Ti ratio. It was found that the leakage current was reduced in MIS capacitor with high quality $SiO_2$ layer was grown on bare p-Si substrate by thermal oxidation. The BST MIS structure showed relatively high capacitance even though it is the combination of high-dielectric BST thin films and $SiO_2$ layer. The charge state densities of the MIS capacitors and Current-voltage characteristics of the MIS capacitor were investigated. By applying $SiO_2$ layer between BST thin films and Si substrate, low leakage current of $10^{-10}$ order was observed.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년도 추계학술발표대회 논문집
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• pp.217-222
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• 2009

This study is lately stand on the basis of the importance for global warming and environment and accept changes of the paradigm of the 21st century. also it is to start architecturial access that suggest to solutions about environment, energy and health problems in high-rise residential architecture that lately the importance for global warming and environment. Spacially since 1990, high-rise residential architecture has developed into increase rapidly, and nowdays, this has become one of the new residence type. but this have diverse problems. For this reason, this building faced neccessary to improve living space and obtain to eco-friendiness and sustainability. Therefore, this study is focused to environment-friendly architectural certification in Korea and other countries, aims to suggest planning and technical elements from this system. Through 11 cases of high-rise residential architecture certified sustainable certification system, this study drew out tendency and charateristics of main strategy elements. These analysis will express informations of current level and also suggest to direction for improvement in quality of high-rise residence.

• Journal of Microbiology and Biotechnology
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• 제4권3호
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• pp.215-221
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• 1994

Two strains of yeast (RA-74-2 and RA-912) showing superior fermenting ability at a high temperature were isolated from soils and wastewaters by an enrichment culture method. Based on the morphological and physiological charateristics, the two strains were identified as Saccharomyces cerevisiae and Kluyveromyces marxianus, respectively. RA-74-2 was able to grow upto $43^{\circ}C$ and sustain similar fermenting ability in the temperatures range from 30 to $40^{\circ}C$. In addition, the sugar- and ethanol-tolerance of RA-74-2 were 30% (w/v) glucose and 10% (v/v) ethanol, which appeared to be higher than those of nine other industrial yeast strains currently being used in the alcohol factories. The thermotolerant ethanol fermenting yeast RA-912 showed identical growth in the temperatures range from 35 to $45^{\circ}C$ and was resistant to various heavy metals. The quality and quantity of byproducts of the isolated yeast strains in fermentation broth after fermentation at $40^{\circ}C$ and $45^{\circ}C$ were similiar with those obtained at $30^{\circ}C$. These results show that RA-74-2 can be adopted for the ethanol fermentation process where the expenses for cooling system is significant, and suggest that RA-912 may be applied in either SSF(simultaneous saccharification and fermentation) or Flash-fermentation process and RA-912 may be used as a gene donor for the development of thermotolerant ethanol-fermenting yeasts.

• 전기의세계
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• 제16권2호
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• pp.1-8
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• 1967

From the discovery of Alago's disk, a number of trials and efforts have been concentrated on a small-sized and light-weighted induction motor. They have devoted themseleves, however, mainly to a improvement of cooling effect, a proper weight-distribution of copper and iron and desirable number of slots. In consequence, such an effort restricted only to the field of design, has resulted in unsatisfactory developments in the insulating materials consisting of the main parts of an induction motor. The quality of fibre and paper which are used as class-A insulation materials with their "compound" and "varnish" has been increased to some extent. Similarly Class-B insulation materials like asbest mica has been almost a combination of inorganic and binding materials. But nowadays synthesic chemistry is making a remarkable progress. So it comes possible for us to have silicon resin and other good ones of similar charateristics. And even a thin silicon resin insures us to get excellent heat-pro f and insulation, so a better space factor and cost-down in motor design have come possible in most advanced nations of the world, but not in our country. Furthermore, a consideration of productivity and economy in manufacturing process has been neglected by a majority of engineers. This is more unpleasant und more undesirable. I think this rational method of induction motor design using new synthesic resin will devote in making your productivity and economy better. And the nation-wide standard value of electric motor size is sited here. size is sited here.

• 한국지반공학회논문집
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• 제24권2호
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• pp.37-44
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• 2008

절취사면의 붕괴는 지질 및 지형적인 요건과 수리적인 요건 등 매우 다양한 요인들이 복합적으로 작용하여 발생한다. 그러나 현행 절취사면의 사전 및 사후 유지관리 단계에서 복잡한 지질조건에 따른 안정성 저해에 미치는 영향을 평가함에 있어 매우 미흡한 실정이다. 본 연구에서는 국내 유지관리 주체별 현황 및 암종별 붕괴 특성 및 유지관리 사례분석 등을 실시하고 이를 통하여 암종별 특성이 고려된 국내 절취사면의 유지관리 방안을 제시하고자 한다.