• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.7-12
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• 2004

탄화규소 전력반도체 소자는 실리콘 전력반도체 소자에 비해 우수한 물질특성을 갖고 있어 성능 측면에서 뿐 만 아니라 전력변환장비의 크기를 획기적으로 줄일 수 있는 새로운 반도체 소자이다. 특히 unipolar 계열의 소자에서 괄목할 만한 특성을 보이고 있다. 현재 쇼트키 장벽 다이오드의 경우 5kV급, UMOSFET의 경우 3kV급의 소자까지 보고되고 있으며 반도체 물질 중에서 가장 활발히 연구가 진행되고 있는 분야 중의 하나이다. 단결정성장 분야에서도 3인치 급이 상용화 되었으며 4인치 크기의 웨이퍼의 상용화가 조만간 실현될 것으로 기대되고 있다. 이러한 기술적 발전을 토대로 600V, 1200V급 쇼트키 다이오드가 PFC boost 용으로 시판되고 있으나 아직은 다른 반도체 소자에 비해 미미한 실정이다. 현재에는 $250^{\circ}C$까지의 온도영역에서 실리콘 SOI(Silicon on Insulator) 소자가 주로 사용되고 있다. 그러나 $300^{\circ}C$를 넘는 온도 영역에서는 실리콘으로는 한계가 있고, 특히 SOI는 전력소자에 적용하기는 한계가 있어 주로 저전력 고온소자가 필요한 부분에 적용이 되고 있다. 따라서 전력용에 적합한 고온소자로 탄화규소 소자의 연구가 활발히 진행되고 있다. 현재의 추세로 보아 $200-300^{\circ}C$ 영역의 응용분야에서는 SOI와 탄화규소가 함께 적용될 것으로 예상되며, $300^{\circ}C$를 넘는 온도영역에서는 탄화규소 소자의 우월적 지위가 예상된다. 이러한 이유로 탄화규소 반도체소자의 응용 분야는 크게 확대될 것으로 예상되며 국가적 차원의 지원 및 육성이 요구되는 분야 중의 하나이다.t로 사용한 소자보다 발광 소광 현상이 적게 일어난 것에 기인하였다고 생각된다. 두 소자 모두 $40mA/cm^2$ 에서 이상적인 화이트 발란스와 같은(0.33,0.33)의 색좌표를 보였다.epsilon}_0=1345$의 빼어난 압전 및 유전특성과 $330^{\circ}C$의 높은 $T_c$를 보였고 그 조성의 vibration velocity는 약4.5 m/s로 나타났다.한 관심이 높아지고 있다. 그러나 고 자장 영상에서의 rf field 에 의한 SAR 증가는 중요한 제한 요소로 부각되고 있다. 나선주사영상은 SAR 문제가 근원적으로 발생하지 않고, EPI에 비하여 하드웨어 요구 조건이 낮아 고 자장에서의 고속영상방법으로 적합하다. 본 논문에서는 고차 shimming 을 통하여 불균일도를 개선하고, single shot 과 interleaving 을 적용한 multi-shot 나선주사영상 기법으로 $100{\times}100$에서 $256{\times}256$의 고해상도 영상을 얻어 고 자장에서 초고속영상기법으로 다양한 적용 가능성을 보였다. 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는 피험자의 머리 움직임에 의하여 도파민 유리가 과대평가되었으며 이는 이 연구에서 제안한 영상정합을 이용한 움직임 보정기

• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.205-212
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• 2004

Recently, as concerns over environmental issues are raised more and more trend to use recycled waste for producing construction materials is also raised. Especially, a case of waste resin is considerably destroying the environment due to disposal way that most waste resin produced is disposed of landfill. This study is performed by polymer concrete with recycled PET resin in terms of obtaining safely clean construction resources and protection of environment. High setting shrinkage and sensitivity to heat are main disadvantages of Polymer Concrete (PC) despites of a lot merits. The aim of this study is to investigate basic properties such as setting shrinkage, length change and sensitivity to heat about PET recycled polymer concrete. The other is to check the possibility of use of Montmorillonite as one of a lot of additive without special coupling agent. As results of experiments, various properties of polymer concrete with recycled PET resin are similar with conventional PC except that polymerization time is longer. Montmorillonite was efficiently used to reduce setting shrinkage, length change and coenicient of thermal expansion related to heat with enhanced strength

• Spatial Information Research
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• v.20 no.1
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• pp.81-90
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• 2012

When analyzing geographical phenomena, two properties need to be considered. One is the spatial dependence structure and the other is a variation or an uncertainty inhibited in a geographic space. Two problems are encountered due to the properties. Firstly, spatial dependence structure, which is conceptualized as spatial autocorrelation, generates heterogeneous geographic landscape in a spatial process. Secondly, generic statistics, although suitable for dealing with stochastic uncertainty, tacitly ignores location information im plicit in spatial data. GIS is a versatile tool for manipulating locational information, while spatial statistics are suitable for investigating spatial uncertainty. Therefore, integrating spatial statistics to GIS is considered as a plausible strategy for appropriately understanding geographic phenomena of interest. Geographic hot-spot analysis is a key tool for identifying abnormal locations in many domains (e.g., criminology, epidemiology, etc.) and is one of the most prominent applications by utilizing the integration strategy. The article aims at reviewing spatial statistical perspective for analyzing spatial processes in the framework of GIS by carrying out empirical analysis. Illustrated is the analysis procedure of using spatial scan statistic for detecting clusters in the framework of GIS. The empirical analysis targets for identifying spatial clusters of breast cancer incidents in Erie and Niagara counties, New York.

• Tuberculosis and Respiratory Diseases
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• v.59 no.3
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• pp.272-278
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• 2005

Background : The immune responses mediated by CD8+T cells are known to be significant in controlling M. tuberculosis infections. In order to determine the role of cytotoxic CD8+T cells in the protective immune mechanism in latently infected subjects, this study examined whether or not the cytotoxic immune responses of CD8+T cells specific to the M. tuberculosis somatic antigens are induced in BCG vaccinated healthy subjects. Methods : Cytotoxicity and $IFN-{\gamma}$ elispot assays were used to investigate the activities of CD8+T cells specific for the $thyA_{30-38}$ peptide epitope in circulating peripheral blood mononuclear cells (PBMC) from BCG-vaccinated HLA-A*0201 and A*0206 subjects. Results : The results indicate the cytotoxic and $IFN-{\gamma}$ immune responses of CD8+T cells specific for $thyA_{30-38}$ were induced in BCG vaccinated healthy subjects. Conclusion : The cytotoxic and $IFN-{\gamma}$ responses by CD8+T cells specific for the M. tuberculosis somatic antigens are induced in BCG-vaccinated subjects, and appear to be involved in the protective immune mechanism in latently infected people against a M. tuberculosis infection.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.388-393
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• 2003

도시화 속도의 증가와 더불어 3차원 자료 획득의 출처가 다양해지연서, 도로 및 건물경계선과 같은 선형 GIS 정보에 대한 신속한 갱신 또한 요구되고 있다. 임의의 출처 자료로부터 대상 자료를 갱신하기 위해서는 가장 먼저 두 자료간의 위치 관계를 결정하여야 하며, 특히 영상정보와 같은 출처 자료와 GIS 자료와 같은 대상 자료간의 위치 관계를 결정하기 위하여 기존에 제시되어온 대부분의 방법들은 두 개 자료간의 관계를 정의 할 수 있는 기준정과 같은 정확한 점 정합 요소(point matching entities)를 요구하고 있다. 따라서 정확한 정합 요소들을 획득할 수 없는 경우 영상과 GIS 자료간의 위치 관계를 결정할 수 없을뿐더러 위치 관계 정립의 결과는 정합 요소들의 분포 및 정확도에 매우 의존하게 된다. 또한 이러한 점 정합 요소들을 정의하기 위해서는 대부분의 경우 수동적으로 이루어질 수밖에 없다. 따라서 본 연구에서는 영상 및 GIS 자료의 선형 정보를 이용하여 정확한 점 정합 요소들을 모르더라도 영상과 GIS 자료간의 위치 관계를 결정할 수 있는 기법을 제시하고자 한다. 사용된 알고리즘은 개선된 Hough 변환(Modified Hough Transform)을 기반으로 다수의 선형 정보 중에 정합되는 요소들을 자동으로 찾아내고 이들을 최소제곱법으로 풀이함으로써 두 데이터간의 기하학적 변환 관계를 결정하는 기법이다. 본 연구에서는 이와 같은 접근을 통해 데이터간의 기하학적 변환 관계를 결정한 후, 영상 상에는 존재하지만 GIS 자료에는 존재하지 않는 선형 정보에 대한 갱신 여부를 확인하고 갱신함으로써 3차원 위치 자료의 자동 생성에 대한 가능성을 제시하고자 한다.로 갈수록 퇴적이 우세한 것으로 관측되었다.보체계의 구축사업의 시각이 행정정보화, 생활정보화, 산업정보화 등 다양한 분야와 결합하여 보다 큰 시너지 효과와 사용자 중심의 서비스 개선을 창출할 수 있는 기반을 제공할 것을 기대해 본다.. 이상의 결과를 종합해볼 때, ${\beta}$-glucan은 고용량일 때 직접적으로 또는 $IFN-{\gamma}$ 존재시에는 저용량에서도 복강 큰 포식세로를 활성화시킬 뿐 아니라, 탐식효율도 높임으로써 면역기능을 증진 시키는 것으로 나타났고, 그 효과는 crude ${\beta}$-glucan의 추출조건에 따라 달라지는 것을 알 수 있었다.eveloped. Design concepts and control methods of a new crane will be introduced in this paper.and momentum balance was applied to the fluid field of bundle. while the movement of′ individual material was taken into account. The constitutive model relating the surface force and the deformation of bundle was introduced by considering a representative prodedure that stands for the bundle movement. Then a fundamental equations system could be simplified considering a steady state of th

• Journal of Korea Port Economic Association
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• v.23 no.3
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• pp.79-101
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• 2007

The purpose of this study is to identify key factors of Co-opetition through examining the environmental and structural changes in the ports industry and suggest a few Co-opetition strategies for enhancing our ports capabilities in the long-term. In recent years, the trend toward market liberalization and globalization in ports industry has made rapid progress and it made the competition fiercer. To survive in this rapid changes, the ports have traditionally pursed a competitive strategy. However, an alternative strategy replacing the traditional strategy was introduced: namely, 'Co-opetition' a buzzword combining competition and co operation. Policy proposals this study suggests are the construction of a database regarding costs and benefits of ports for more effective analysis and improving the competitive power of a shipping company operating national flag carriers for achieving the purpose of Co-opetition and adoption of selection and concentration strategy for increasing the possibility of Co-opetition success.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.1-10
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• 2014

Recently, the value and the status of the digital archives that are built individually in the crossroads of oblivion and memory are due to big data has attracted attention globally is confusing. Video data that contains the cultural memory of the digital archive, such as culture, art, life, society, and social conditions of the time, it is a cultural heritage of national common expressed. Also, it remains a trace of history from the various media just like magazines, books, painting, photography, and film. Digital archive system is one of the best research results of media convergence and it has also a good opportunity to take full advantage of the new opportunities and cultural assets. The collection of infinite information of big data in perspective transient that exist at the same time compatibility of big data, it is trying to dismantle the cultural memory of us. It was asserted that must meet the criteria which can correspond to via the new digital era, will be applied to preserve the traditional media. The current image archive is necessary to accommodate proper two different directions.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.5
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• pp.729-735
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• 2009

The objective of this study was to evaluate the quality characteristics of Sulgidduk added with cabbage powder. The moisture contents of Sulgidduk added with cabbage powder ranged from 37.2 to 33.7% and were significantly lower than those of the control. As the amount of cabbage powder increased, the L-value was reduced, while the a- and b-values were increased. In terms of textural characteristics, Hardness, Adhesiveness, Springiness, Cohesiveness, Gumminess, and Chewiness decreased with greater concentrations of cabbage powder. Sensory evaluation revealed that the favorite degree of color, flavor and taste received high increasing scores with increasing addition amounts of cabbage powder, while the Chewiness did not differ significantly (p<0.05) among the samples. The moistness found to be highest in the control, while it decreased as the amount of cabbage powder increased. The overall acceptance was highest as (6.00) for the Sulgidduk (CS6) that contained 6% of the cabbage powder. Overall, the results of this study indicate that adding 6% cabbage powder to Sulgidduk was produced the optimal results, and provided good quality characteristics and high overall acceptance.

• Journal of Dairy Science and Biotechnology
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• v.15 no.1
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• pp.33-44
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• 1997

We investigated the immunological function of cheese whey protein concentrate (CWPC), which is a by-product of cheese production, using mitogenic activity in murine splenocytes as an index. A fraction isolated by gel filtration and anion exchange chromatography of CWPC showed high mitogenic activity, comparable to the activity of lipopolysaccharide (LPS). The fraction was detected as a single band on SDS-PAGE. It contained calcium, inorganic phosphorus, and carbo-hydrate, indicating the active component to be a glycophosphopeptide (GPP) Since pronase digestion of GPP did not reduce its mitogenic activity, carbohydrate rather than peptide may be important in the activity, When applied on an anti-${\beta}$-caseinophosphopeptide (${\beta}$-CPP ) antibody affinity column, the GPP was separated into two components, one with affinity to ${\beta}$-CPP and the other without such affinity. Both the components contained N-linked oligosaccharide chains and had the mitogenic activity. These results demonstrate that cheese whey contains a GPP having strong mitogenic activity

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.273-281
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• 2010

Concentration of antibiotics including a tetracycline group (TCs) of tetracycline (TC), chlortetracycline (CTC), and oxytetracycline (OTC), a sulfonamide group (SAs) of sulfamethoxazole (SMX), sulfathiazole (STZ), and sulfamethazine (SMT), an ionophore group (IPs) of lasalocid (LSL), monensin (MNS), and salinomycin (SLM), and a macrolide group (MLs) of tylosin (TYL) was determined from samples collected from the agricultural soil, stream water, and sediment. For the agricultural soil samples, the concentration of TCs had the highest value among all tested antibiotic's groups due to its high accumulation rate on the surface soils. The lower concentrations of SAs in the agricultural soils may be resulted from its lower usage and lower distribution coefficient (Kd) compared to TCs. The concentration of TCs in stream water was significantly increased through June to September. It would be likely due to soil loss during an intensive rainfall event and a reduction of water level after the monsoon season. A significant amount of TCs in the sediment was also detected due to its accumulation from runoff, which occurred by complexation of divalent cations, ion exchange, and hydrogen bonding among humic acid molecules. To ensure environmental or human safety, continuous monitoring of antibiotics residues in surrounding ecosystems and systematic approach to the occurrence mechanism of antibiotic resistant bacteria are required.