• 대한수의학회지
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• 제40권3호
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• pp.489-496
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• 2000

본 연구에서는 Streptozotocin-induced 당뇨가 혈청과 간장 및 신장조직의 IGF-I, IGFBPs 및 IGF-I carrier protein 특성에 미치는 영향을 조사하였다. 혈액과 조직중의 IGF-I 농도는 방사면역측정법으로 측정하였고, IGFBPs 양상은 Western Ligand Blotting(WLB)으로 관찰하였으며, IGF-I carrier protein의 특성은 column chromatography로 측정하였다. 혈청과 IGF-I 농도는 당뇨군이 대조군에 비하여 유의하게 감소하였다 (p<0.01). 당뇨군은 대조군에 비하여 간장 IGF-I 농도는 유의하게 감소한 반면, 신장의 IGF-I 농도는 유의하게 증가하였다(p<0.01). 당뇨군은 대조군에 비하여 혈청과 간장의 IGFBP-3는 감소한 반면, IGFBP-2는 증가하였고, IGFBP-4는 변화가 없었다. 또한 당뇨군은 대조군에 비하여 150kDa carrier protein은 감소하였으며, 50kDa carrier protein은 증가하였다. 이상의 결과를 종합해볼 때 Streptozotocin-induced 당뇨는 혈청 뿐만 아니라 조직의 IGF-I/IGFBP system 변동에 영향을 미침을 알 수 있었다.

• 한국항만학회지
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• 제2권1호
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• pp.29-73
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• 1988

Since the middle of 1950's when sea transportation service by container ship was established, containerization has been rapidly spread over the world with realization of intermodalism, and becomes an index of economy growth of a country. Our country has established Pusan Container Terminal at Pusan harbour in 1978 in step with worldwide trend of containerization, and is constructing New Container Terminal at Pusan outharbour which will be completed in 1990. This paper aims to make a quantitative analysis of the Pusan Container Terminal system through the computer simulation, especially focusing on its subsystems such as ship stevedoring system, storage system and transfer system. First, the capacity of various subsystems are evaluated and it is checked whether the current operation is being performed effectively through the computer simulation. Secondly, the suggestion is presented to improve the operation by considering the throughput that Pusan Container Terminal will have to accept until 1990, when New Container Terminal will be completed. The results are as follows ; 1) As the inefficiency is due to the imbalance between various subsystems at Pusan Container Terminal on the basis of about 1.2 million TEU of container traffic, transfer equipment level must be up to 33% for transfer crane, and free period must be reduced into 4/5 days for export/import. 2) On the basis of about 1.4 million TEU of container traffic, transfer equipment level must be up to $12\%$ for gantry crane, $11\%$ for straddle carrier and $66\%$ for transfer crane, and free period must be reduced into 3/4 days for export/import. 3) On the basis of about 1.7 million TEU of container traffic, transfer equipment level must be up to $25\%$ for gantry crane, $28\%$ for straddle carrier and $100\%$ for transfer crane, and free period must be reduced into 3/4 days for export/import. 4) On the basis of about 2 million TEU of container traffic, transfer equipment level must be up to $25\%$ for gantry crane, $30\%$ for straddle carrier and $110\%$ for transfer crane, and free period must be reduced into 2/3 days for export/import, and it is necessary to enlarge storage yard.

• Archives of Pharmacal Research
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• 제26권6호
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• pp.504-510
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• 2003

The aim of this study is to prepare biodegradable microspheres without the use of surfactants or emulsifiers for a novel sustained delivery carriers of protein drugs. A poly($\varepsilon$-caprolactone)/poly(ethylene glycol)/poly($\varepsilon$-caprolactone) (CEC) triblock copolymer was synthesized by the ring-opening of $\varepsilon$-caprolactone with dihydroxy poly (ethylene glycol) to prepare surfactant-free microspheres. When dichloromethane (DCM) or ethyl formate (EF) was used as a solvent, the formation of microspheres did not occur. Although the microspheres could be formed prior to lyophilization under certain conditions, the morphology of microspheres was not maintained during the filtration and lyophilization process. Surfactant-free microspheres were only formed when ethyl acetate (EA) was used as the organic solvent and showed good spherical micro-spheres although the surfaces appeared irregular. The content of the protein in the micro-sphere was lower than expected, probably because of the presence of water channels and pores. The protein release kinetics showed a burst release until 2 days and after that sustained release pattern was showed. Therefore, these observations indicated that the formation of microsphere without the use of surfactant is feasible, and, this the improved process, the protein is readily incorporated in the microsphere.

• 약학회지
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• 제47권2호
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• pp.110-119
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• 2003

The purpose of the present study was to kinetically investigate the carrier-mediated uptake in the hepatic transport of organic anions, and to simulate the ″in vivo counter-transport″ phenomena, using kinetic model which was developed in this study. The condition that the mobility of carrier-ligand complex is greater than that of free carrier is not essential for the occurrence of ″counter-transport″ phenomenon. To examine the inhibitory effects on the initial uptake of a ligand by the liver, it is necessary to judge whether the true counter-transport mechanism (trans-stimulation) is working or not. The initial plasma disappearance curves of a organic anion were then kinetically analyzed based on a flow model, in which the ligand is eliminated only from the peripheral compartment (liver compartment). Moreover, ″in vive counter-transport″ phenomena were simulated based on the perfusion model which incorporated the carrier-mediated transport and the saturable intracellular binding. The ″in vivo counter-transport″ phenomena in the hepatic transport of a organic anion were well demonstrated by incorporating the carrier-mediated process. However, the ″in vivo counter-transport″ phenomena may be also explained by the enhancement of back diffusion due to the displacement of intracellular binding. In conclusion, one should be more cautious in interpreting data obtained from so-called ″in vivo counter-transport″ experiments.

• 한국재료학회지
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• 제14권1호
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• pp.41-45
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• 2004

P-type $Bi_{0.5}$$Sb_{1.5}$ $Te_3$ thin films were deposited by the flash evaporation technique, and their thermoelectric properties and electronic transport parameters were investigated. The effective mean free path model was adopted to examine the thickness effect on the thermoelectric properties. Annealing effects on the carrier concentration and mobility were also studied, and their variations were analyzed in conjunction with the antisite defects. Seebeck coefficient and electrical resistivity versus inverse thickness showed a linear relationship, and the effective mean free path was found to be 3150$\AA$. No phase transformation and composition change were observed after annealing treatment, but carrier mobility increased due to grain growth. Carrier concentration decreased considerably due to reduction of the antisite defects, so that electrical conductivity decreased and Seebeck coefficient increased. When annealed at 473 K for 1 hr, Seebeck coefficient and electrical conductivity were $160\mu$V/K and 610 $W^{-1}$ $cm^{ -1}$, respectively. Therefore, the thermoelectric quality factor were also enhanced to be $16\mu$W/cm $K^2$.>.

• Strategy21
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• 통권34호
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• pp.149-177
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• 2014

Today distant oceans around the world are regarded as a major 'global commons' for international trade and transportation. Korea is not an exception, because Korea hugely depends on sea lines of communication (SLOC) for supplying vital commodities such as food and energy resource. As a result, assuring a free and safe use of distant ocean beyond territory is also an important agenda for Korea's maritime security. However there are a number of challenges for Korea to enjoy a free and safe use of distant ocean; dangers of regional maritime conflict in East Asia, naval arms race of China and Japan, and concerns on possible decline of U.S naval presence and power projection capabilities. These factors provide a reasonable basis for Republic of Korea Navy (ROKN) to pursue capabilities for major naval operations at distant ocean in a long-term perspective toward the year 2030. The introduction of aircraft carrier and nuclear-powered submarine is a key requirement for achieving this goal. ROKN needs to acquire a 'multi-role strategic landing platform' type of light aircraft carrier, which takes a role to escort naval task force by providing air superiority at distant ocean. Additionally nuclear-powered submarine will offer ROKN a formidable power to carry out offensive missions effectively at distant ocean.

• 한국항행학회논문지
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• 제15권4호
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• pp.502-509
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• 2011

GPS 반송파를 이용한 정밀 항법 수행 시 미지 정수 결정이 필수적이다. 한번 결정된 미지 정수는 사이클 슬립이 발생하지 않는 한 변하지 않는다. 그러나 전파 관측 환경의 변화에 따라 사이클 슬립이 발생하게 되며, 이러한 상황에서 연속적인 항법 정보 제공을 위한 적절한 대응 조치를 취해 주어야 한다. 그러나 이러한 조치들은 매우 번거로우며, 소프트웨어적인 복잡성을 야기 한다는 문제가 있다. 본 논문에서는 미지 정수 유지 및 재검색 과정을 단순화하기 위해 시스템 운동 모델을 이용하여 사이클 슬립에 무관한 위치 제공 기법을 제안하였다. 제안된 방법은 고의적으로 사이클 슬립을 발생시켜 대응 성능을 확인하였으며, 이 결과 사이클 슬립과 무관하게 항법 정보를 제공할 수 있음을 확인하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권1호
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• pp.65-71
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• 2011

Seakeeping analysis has progressed from the linear frequency-domain 2D strip method to the nonlinear timedomain 3D panel method. Nevertheless, the violent free surface flows such as slamming and green water on deck are beyond the scope of traditional panel methods based on potential theory. Recently, Computational Fluid Dynamics (CFD) has become an attractive numerical tool that can effectively deal with the violent free surface flows. ABS, as a classification society, is putting forth a significant amount of effort to implement the CFD technology to the advanced strength assessment of modern commercial ships and high-speed naval craft. The main objective of this study is to validate the CFD technology as a seakeeping tool for ship design considering fully nonlinear three-dimensional slamming and green water on deck. The structural loads on a large container carrier were successfully calculated from the CFD analysis and validated with segmented model test measurements.

• 대한화학회지
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• 제9권2호
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• pp.96-100
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• 1965

우리나라 硏究用 原子爐 TRIGA Mark Ⅱ에 依한 無擔體의 Fe-59를 製造할 目的으로 分離法과 放射化學的 純度 및 核反應斷面積을 檢討하였다. 分離된 Fe-59를 ${\gamma}$-ray spectrometry와 半減期測定에 依하여 純度를 定한 結果 99.9%以上이었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.749-750
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• 2008