• 전기화학회지
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• 제6권1호
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• pp.68-71
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• 2003

전지 성능을 저하시키지 않고 연료극 및 공기극의 귀금속 촉매량을 줄이기 위하여 다층막 전극을 이용한 직접메탄을 연료전지의 성능특성을 조사하였다. 다층막 전극 즉, 연료극과 공기극에 사용된 촉매사용량과 나피온 막의 종류를 변화시키며 최종성능을 측정하였다 본 실험에서 사용된 촉매량은 연료극이 $3-4mg/cm^2$ 공기극이 $1-2mg/cm^2$이다. 본 실험에서는 나피온 115를 사용한 MEA3의 $90^{\circ}C$, 2기압에서 측정 결과 최대 전력밀도인 $230mW/cm^2$를 나타내었다. 이 결과는 현재 시판되고 있는 상용전극과 거의 같은 수준의 성능을 보여주고 있는 반면, 금속 촉매의 양은 기존의 상용전극과 비교하여 약 $50\%$ 정도 감소된 것이다.

• 무역상무연구
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• 제18권
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• pp.159-188
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• 2002

International joint ventures are usually formed and managed by domestic companies and foreign investors for the common objectives. They offer an opportunity for each partner to benefit significantly from the comparative advantages of the other. Local partners bring knowledge of the domestic market; familiarity with government bureaucracies and regulations; understanding of local labor markets; and existing manufacturing facilities. Foreign partners can offer advanced process and product technologies, management know-how, and access to export markets. In Korea, joint ventures have been encouraged to usher in foreign investors with foreign currency capital badly needed during the IMF financial crisis. In the meantime, Korean laws and regulations with respect to joint ventures have been largely overhauled to promote foreign direct investment (FDI) both inbound and outbound. They include four types of FDI, i.e., acquisition of foreign stocks, provision of long-term loans, participation in joint operations like resources development, and establishment of foreign offices. From the legal point of view, the formal joint venture agreement must be an offspring of a series of tough negotiations between domestic and foreign partners. They usually stress the long-term relationship with the good will and dedication to each other, and restrict the free transfer of stocks. Both partners are earnestly interested in the ownership and management of the joint venture. So they keep a close eye on the articles of incorporation, changes of business environment, conflict resolution methods, transparency of accounting and other financial matters. When a multinational corporation (MNC) is involved in the joint venture, conflicts over management strategies, marketing and other issues take place more often than not between the MNC and local partners. We have to pay attention to joint ventures, particularly, in China and North Korea. As witnessed in other transition economies, China is eagerly bringing in foreign direct investments for the development of nation's economy. China encourages foreign investors to establish ordinary joint ventures, contractual joint ventures, solely invested foreign capital companies and jointly operated development companies with local partners. In North Korea, however, joint ventures have a different meaning like contractual joint ventures in China, in which North Korean partners have an initiative in the management. Rather, jointly operated companies or simply processing-for-wage companies are recommended in view of the unpredictable legal infrastructure in North Korea.

• Journal of Yeungnam Medical Science
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• 제7권1호
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• pp.19-27
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• 1990

Slow twitch soleus와 fast twitch plantaris근의 운동, insulin, 전기자극에 대한 반응을 시험관 내에서 $^{14}C$-glucose를 이용한 glycogen합성능으로 비교하고 협력근 절제 4주후에 유도한 대상성비후근의 glycogen의 합성능을 같은 방법으로 평가하여 지속적인 과부하에 따른 각 근섬유의 반응을 비교하고자 한 본 연구의 결과를 요약하면 다음과 같다. 대조군의 soleus에서는 glycogen으로 incorporation되는 glucose양으로 볼때 운동에 의한 증가는 없었으나 insulin, 전기자극 등의 인자에 의해서는 증가하였으며 운동이 이들 인자들과 합쳐 졌을때는 이들의 작용을 증폭 시켰다. 그러나 plantaris에서는 운동과 전기자극을 합한 군과 모든자극을 함께 가한 군에서만 유의한 증가를 보여서 insulin이나 glucose대사의 관점에서 볼때 soleus가 훨씬 활동적임을 알 수 있었다. 협력근 절제로 인한 4주간의 과부하로 인한 비후군의 glycogen합성능은 soleus에서 대조군의 그것과 양상은 비슷하였으나 그 절대 량에서 크게 못미쳤으며 plantaris에서는 대조군과 매우 유사한 반응을 나타내었다. 이와같은 결과로 볼때 협력근 절제 4주후에 여러 효소의 활동도가 안정상태에 이른다는 여러 보고에 기초하면 지속적인 과부하에 대한 각 근섬유의 반응양상이 차이가 나서 fast twitch근의 근활동이 더 향상되는 것으로 사료된다.

• 한국잡초학회지
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• 제7권1호
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• pp.98-106
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• 1987

Carbofuran이 벼 생육(生育)에 미치는 영향을 알기 위해 1981년(年)부터 1986년(年)까지 영남작물시험장(嶺南作物試驗場)에서 벼종자(種子) 발아영향(發芽影響), 못자리 묘생육영향(苗生育影響), 본답(本畓) 벼생육영향(生育影響) 및 기상재해영향(氣象災害影響) 등(等)을 통(通)하여 구명(究明)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. Carbofuran 처리(處理)는 벼종자(種子) 발아(發芽)에 영향을 미쳤는데 지상부(地上部)보다 지하부(地下部)의 생육(生育)에 대한 영향이 컸다. carbofuran 농도(濃度)가 높아짐에 따라 전체종근수(全體種根數)는 감소(減少)되나 뿌리당(當) 길이는 50ppm까지 길어졌다. 2. 보온절충식(保溫折衷式)못자리에서의 carbofuran 처리(處理)는 무비구(無肥區)에서 3요소비료(要素肥料) 표준시용량(標準施用量) 정도(程度)의 생육(生育)까지 증진(增進)시켰고 또한 통일형(統一型) 품종(品種)의 적고피해(赤枯被害)를 회복(回復)시키는 효과(效果)가 있었는데 적고회복(赤枯回復) 요인(要因)으로는 파괴(破壞)된 엽록소(葉綠素) 자체(自體)의 회복(回復)이 아니라 묘생육량(苗生育量) 증대(增大)에 의한 것이었다. 그리고 carbofuran 처리시기효과(處理時期効果)에 있어서는 파종전(播種前) 처리(處理)가 가장 높고 다음으로는 vinyl 제거전(除去前), vinyl 제거후(除去後)의 순(順)이었다. 3. 본답(本畓)에서의 벼 벼생육증진효과(生育增進効果)는 이앙전(移秧前) 처리(處理)가 이앙(移秧) 25일(日) 후(後) 처리(處理) 보다 그리고 1 모작답(毛作畓)보다 2모작답(毛作畓)에서 높은 경향(傾向)이었고, 증진(增進)되는 생육형질(生育形質)로는 년차간(年次間) 및 품종간(品種間) 다소(多少) 차이(差異)가 있지만 간장(稈長), 수수(穗數), 영화수(穎花數) 및 추수력(抽穗力) 등(等)이었는데 그 중(中)에서도 수수증대(穗數增大) 요인(要因)이 가장 컸다. 4. Carbofuran 처리(處理)는 감수분열기(減數分裂期)와 출수기(出穗期)의 저온피해(低溫被害)와 침관수(浸冠水) 피해경감효과(被害輕減効果)가 있었으며 주요(主要) 생육증진요인(生育增進要因)으로는 임실비율(稔實比率), 등숙비율(登熟比率) 및 광합성능력증진(光合成能力增進)에 있었다.

• IMMUNE NETWORK
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• 제2권2호
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• pp.109-114
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• 2002

Background: To investigate the role of sympathetic nervous system (SNS) in moxibustion-induced immunomodulation, the effects of chemical sympathectomy on moxibustion-induced changes in splenic NK cell cytotoxicity, T and B cell proliferation were studied in Sprague-Dawley male rats. Methods: Chemical sympathectomy was achieved with intraperitoneal injection of 6-hydroxydopamine 50 mg/kg/day for 3 successive days. Direct moxibustion (6-minute interval, 9 moxa ball, each of which weighing 0.007 g and burning for 40 seconds) was applied on unilateral anterior tibial muscle region where Zusanli (ST36) acupoint is located, once a day for 7 successive days. NK cell cytotoxicity was measured by $4hr-^{51}Cr$ release assay. Mitogen-induced lymphocyte proliferation was analyzed by [$^3H$]-thymidine incorporation assay. Results: NK cell cytotoxicity was suppressed by moxibustion, more in sympathectomized rats than in vehicle-treated rats. T cell proliferation induced by concanavalin A was not affected by moxibustion. B cell proliferation induced by lipopolysaccharide showed no significant change in vehicle-treated rats, but an increase in sympathectomized rats by moxibustion. Sympathectomy alone induced augmentation of NK cell cytotoxicity and suppression of T cell proliferation. Conclusion: These results suggest that SNS has no direct relation with moxibution-induced immunomodulation but has an important role in the mechanism to keep the homeostasis of immune system by tonically inhibiting excessive changes of various immune components.

• Korean Chemical Engineering Research
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• 제47권3호
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• pp.275-280
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• 2009

바나듐이 담지된 3차원 입방구조의 V-KIT-6를 Pluronic P123 공중합체를 구조형성제로 사용하고, 부탄올을 보조 계면활성제로 사용하여 TEOS와 $NH_4VO_3$로부터 수열합성법으로 제조하였다. 제조한 V-KIT-6는 좁은 기공분포(~6.0 nm)를 가지고 넓은 비표면적(${\sim}1,000m^2/g$)을 보여주었다. V-KIT-6에서 V의 배위 특성 등은 $^{51}V$ 스핀 공명 NMR과 ESR을 이용하여 분석하였다. 제조된 V-KIT-6는 테트라부틸 하이드로 퍼옥사이드(TBHP)를 산화제로 사용한 스티렌의 직접산화반응에서 우수한 촉매활성을 나타내었다.

• 한국토양비료학회지
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• 제26권4호
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• pp.299-303
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• 1993

석탄회중의 B성분의 식물독성을 검토하기 위하여 B함량이 다른 석탄회를 작토중의 20% 해당량을 토양에 시용하고 콩을 재배하여 1년차 비효 및 2년차 잔효시험으로 수행하였다 B함량이 높은 석탄회는 20% 시용구에서 콩의 생육이 극히 불량하였으며 수량도 거의 전무상태이었으나 B함량이 보통인 석탄회의 시용으로 생육과 수량이 대조에 비해 양호하여 석탄회 다량시용시 석탄회중의 B함량의 검토가 요구되었다.

• 한국세라믹학회지
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• 제45권2호
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• pp.119-125
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• 2008

The FAS(Fluoroalkylsilane)/Nafion inorganic-organic composite electrolyte membrane was successfully fabricated through sol-gel method. The FAS having hydrophobic functional group and silanol ligands is impregnated in $Nafion^{(R)}$ membrane to reduce methanol crossover. The prepared FAS/Nafion inorganic-organic composite electrolyte membrane consist of the hydrophobic FAS-derived silicate nano-particles and $Nafion^{(R)}$ matrix showed decrease of methanol crossover and reduction of humidity dependence without large sacrifice of proton conductivity. The microstructural analysis of the composite membranes was performed using FESEM and FTIR. And the effect of the incorporation of the hydrophobic FAS-derived silicate nano-particles into $Nafion^{(R)}$ membrane was investigated via solvent uptake, membrane expansion rate, humidity dependency of proton conductivity and contact angle measurement.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1165-1168
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• 2002

Knowledge acquisition is the process that extracts the required knowledge from available sources, such as experts, textbooks and databases, for incorporation into a knowledge-based system. Knowledge acquisition is described as the first step in building expert systems and a major bottleneck in the efficient development and application of effective knowledge based expert systems. One cause of the problem is that the process of human reasoning we need to understand for knowledge-based system development is not available for direct observation. Moreover, the expertise of interest is typically not reportable due to the compilation of knowledge which results from extensive practice in a domain of problem solving activity. This is also a problem of modeling knowledge, which has been described as not a problem of accessing and translating what is known, but the familiar scientific and engineering problem of formalizing models for the first time. And this formalization process is especially difficult for knowledge engineers who are often faced with the difficult task of creating a knowledge model of a domain unfamiliar to them. In this paper, we propose an automated knowledge acquisition tool which is based on an implementation of the Inferential Modeling Technique. The Inferential Modeling Technique is derived from the Inferential Model which is a domain-independent categorization of knowledge types and inferences ［Chan 1992］. The model can serve as a template of the types of knowledge in a knowledge model of any domain.

• ALGAE
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• 제30권2호
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• pp.103-119
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• 2015

Photosynthetic rates of the large centric diatom Coscinodiscus granii were measured by means of multicolor variable chlorophyll fluorescence imaging, single cell $^{14}C$ assimilation, and optical $O_2$ sensor measurements during light acclimatization of cultures grown at five different irradiances: 50, 150, 235, 332, and $450{\mu}mol$ photons $m^{-2}\;s^{-1}$. Photo-acclimatization was evident from changes of cellular chlorophyll a content, growth rates, and light response curves. Each of the applied methods evaluates different parts and reactions in the photosynthetic apparatus, which makes a direct quantitative comparison of rates difficult, although a different degree of correlation were found between all three methods. However, when used in combination, they provide information about the internal relationship of photosynthetic pathways as well as the variation in photosynthetic capacity between individual cells within a single algal culture.