• Applied Microscopy
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• v.32 no.2
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• pp.91-105
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• 2002

Urea transport in the kidney is mediated by a family of transporter proteins that includes renal urea transporters (UT-A) and erythrocyte urea transporters (UT-B). The cDNA of five isoforms of rat UT-A, UTA1, UT-A2, UT-A3, UT-A4, and UT-A5 have been cloned. The purpose of this study was to examine the expression of UT-A (L194), which marked UT-A1, UT-A2 and UT-A4. Male Sprague-Dawley rats, weighing approximately 200 g, were divided into three group: control rats had free access to water, dehydrated rats were deprived of water for 3 d, and water loaded rats had free access to 3% sucrose water for 3 d before being killed. The kidneys were preserved by in vivo perfusion through the abdominal aorta with the 2% paraformaldehyde-lysine- periodate (PLP) or 8% paraformaldehyde solution for 10 min. The sections were processed for immunohistochemical studies using pre-embedding immunoperoxidase method and immunogold method. In the normal rat kidney, UT-A1 was expressed intensely in the cytoplasm of the inner medullary collecting duct (IMCD) cell and UT-A2 was expressed on the plasma membrane of the terminal portion of the shortloop descending thin limb (DTL) cells (type I epithelium) and of the long-loop DTL cells (type II epithelium) in the initial part of the inner medulla. Immunoreactivity for UT-A1 in the IMCD cells, was decreased in dehydrated animals whereas strongly increased in water loaded animals compared with control animals. In the short-loop DTL, immunoreactivity for UT-A2 was increased in intensity in both dehydrated and water loaded groups. However, in the long-loop DTL of the outer part of the inner medulla, immunoreactivity for UT-A2 was markedly increase in intensity in dehydrated group, but not in water loaded group. In conclusion, in the rat kidney, UT-A1 is located in the cytoplasm of IMCD cells, whereas UT-A2 is located in the plasma membrane of both the short-and long-loop DTL cells. Immunohistochemistry studies revealed that UT-A1 and UT-A2 may have a different role in urea transport and are regulated by different mechanisms.

• Journal of Life Science
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• v.17 no.10
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• pp.1347-1353
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• 2007

The changes of glycoconjuagates (GCs) in rat kidney due to maturation were studied from samples of fetal and postnatal kidneys by lectin histochemistry. Rat kidneys of perinatal ages and adults were fixed in 4% paraformaldehyde and were stained with nine kinds of biotinylated lectins. The immature forms of the renal developmental stage such as vesicles and ureteric bud were observed in the cortex as late as day 14 of postnatal life, but the histological appearance of the weaning kidney was similar to that observed in adults. As for histochemical properties of GCs in the glomeruli, Con A affinity tended to increase with aging, but both RCA-1 and LCA affinities showed a transient increase in immature glomeruli of neonatal rats. DBA affinity with SBA, PNA, BSL-1 and RCA-1, additional Con A one in proximal tubule, were increased in both proximal and distal tubules according to maturation. In contrast to this, transient intensive LCA affinity were demonstrated in immature proximal and distal tubule of neonatal rats. In the collecting tubules, DBA, SBA, PNA and sWGA affinities tended to increase according to maturation, but transient increase for BSL-1, RCA-1 and LCA affinities were detected in neonatal rats. The present results suggest that the mature glycosylation pattern of the kidney undergoes profound changes during maturation and is probably associated with functional maturation of the kidney.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.4
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• pp.417-424
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• 2011

A fuel assembly consists of five major components, i.e., a top end piece (TEP), a bottom end piece (BEP), spacer grids (SGs), guide tubes (GTs) and an instrumentation tube (IT); in addition, it also includes fuel rods (FRs). The TEP/BEP should satisfy stress intensity limits according to the conditions A and B of ASME, Section III, Division 1-Subsection NB. In a dual-cooled fuel assembly, the array and position of fuel rods are different from those in a conventional PWR fuel assembly; these changes are necessary for achieving power uprating. The flow plates of the TEP and BEP have to be modified accordingly. The pattern and shape of the flow holes were newly designed. To verify the strength compatibility, the Tresca stress limit according to the ASME code was investigated in the case of an axial load of 22.241 kN. In this paper, the stress linearization procedure for strength evaluation of a newly designed TEP is presented.

• Journal of the Korean Geographical Society
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• v.45 no.4
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• pp.461-477
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• 2010

Recent environmental issues such as genetically modified organisms, the loss of biodiversity, climate change, and nuclear waste cannot be reduced to a matter of science or society and explained through nature-society dualist approaches because of their complexity and heterogeneity. This paper examines how nature-society dualism has been embedded in science studies and geography and how this dualism can be overcome. Actor-Network Theory as an attempt to overcome this nature-society dualism is appropriate in analysing "strange imbriglio" of biology, politics, technoscience, market, value, ethics and facts that constitute our society by focusing on heterogeneous association, and can contribute to providing a useful framework to solve environmental problems.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.228-236
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• 1996

An electrolysis system with a vertically circulating mercury capillary bundle electrode was developed with a very large electrode area in a minimum space. This system was operated by forcedly feeding mercury and aqueous solution containing metal ion into a fiber bundle packed densely within a small porous glass tube. In order to test the characteristics and stability of the electrolysis system, the reduction voltammograms of uranyl and ferric ions were measured with changes of the mercury flow rate and the aqueous flow rate. The aqueous flow rate had a large effect on the electrochemical reaction of metal ion occurring at the interface between the mercury and the aqueous solution and had to be regulated as an appropriate value to have a good limiting current shape. The limiting current was linearly proportional to the aqueous flow rate, and complete reductions of uranyl and ferric ions were rapidly and continuously accomplished at the potential showing limiting current. With a mercury flow rate high enough to keep a capillary continuum of mercury in the fiber bundle, the mercury flow rate had almost no effect on the electrochemical reaction. This system was confirmed to be effective and stable enough to control rapidly and continuously the oxidation state of metal ions fed into the system under an appropriate aqueous flow rate.

• Journal of Korean Library and Information Science Society
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• v.52 no.4
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• pp.1-21
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• 2021

This study traced the origin and transformation of word library linked with archives in the ancient Near East, and Greece and Rome. First, the word library has two origins. One is derived from the Latin bibliothēkē from the ancient Greek βιβλιοθήκη. The first trace is Pollux's Onomasticon in the second half of the 2nd century, and if considered as a set of literature texts, it is Lipsius's De Bibliothecis Syntagma in 1602. The other was established as an library in the early 14th century after Latin libraria (or librarium) was translated into Old French librairie (or librarie). The word library was coined by Chaucer in 1374. Second, the clay tablet repository that existed in the ancient Near East is close to an archive, but the official name is unknown. However, the Ashurbanipal clay tablet archive is far from the principle of respect for original order and origins emphasized by the archivists, so it is not a royal archive, but a prototype of the royal library. And the official name of the Library of Alexandria was 'Βιβλιοθήκη της Αλεξάνδρειας', and then it was changed to 'ALEXANDRINA BYBLIOTHECE'. Third, In ancient Greece and Rome, archives and libraries were separated. Greece libraries were at the level of a small libraries attached to gymnasiums, and had few independent titles. The names of the Roman libraries often attached to the public baths were mixed with βιβλιοθήκη and Bibliotheca. Finally, the ancient library was succeeded to the cathedral bibliothek, and was transformed into 'bayt al-hikmah' in the Islamic Empire. In Japan, China, and Korea, Japanese-Chinese word library was accepted at the end of the 19th century, but there are many issues that require follow-up research.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.4
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• pp.499-503
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• 2009

Y. R$\acute{e}$ball$\acute{e}$ [11] discussed the representation of necessity measure through the Choquet integral criterian. He also consider a decision maker who ranks necessity measures related with Choquet integral representation. In this paper, we consider a decision maker have an "ambiguity"(say, interval-valued) necessity measure according to their Choquet's expected utility. Furthermore, we prove two theorems which are weak Choquet integral representation of preferences with a monotone set function for interval-valued necessity measures and strong Choquet integral representation of preferences with an interval-valued utility function for necessity measures.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.361-361
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• 2011

하나로 냉중성자원(CNS: Cold Neutron Source)은 원자로 수조내 반사체 탱크에 위치한 수직 조사공에 설치되어 하나로 노심에서 발생하는 열중성자를 감속재인 액체 수소층을 통과시켜 냉중성자를 생산한다. 생성된 냉중성자는 유도관을 통하여 냉중성자 산란장치에 공급되어 이용 연구에 활용된다. 감속재로 사용되는 수소는 헬륨냉동계통의 운전에 따라 수소가 수조내기기 집합체(IPA: In Pool Assembly) 내로 이동되어 액화되어지므로, 극저온의 헬륨가스의 흐름이 중요하다. 헬륨냉동기에 의해 만들어진 극저온인 헬륨은 IPA 내의 수소와 열교환을 하기 위해서 배관을 통해 이동되며, 열손실없이 전달하기 위하여 헬륨 배관은 진공층이 형성된 이중배관으로 설계되어 있다. 헬륨 이중배관은 공급 및 회수 배관으로 구성되어 있으며, 헬륨 배관의 외관에 진공층을 20개의 구간으로 나누어 제작 및 설치되었으며, 각각의 진공도를 유지하고 있다. 이 논문에서는 하나로 냉중성자원 헬륨 이중배관의 특성과 헬륨냉동계통의 운전 및 정지시 온도 변화에 따른 이중배관 진공도의 변화를 분석하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.532-534
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• 2005

본 논문은 자동적인 언어기반자원구축을 위해 신문 말뭉치에서 괄호를 이용하여 추출한 대역어쌍들을 군집화하고 각 군집에서 적합대역어를 선정하는 방법을 제안한다. 기존 연구에서 주로 제시된 음차표기어 대역쌍 추출 방법은 완전한 형태의 영어원어 자소 정보를 이용하기 때문에 약어는 고려대상에서 제외되었다. 그러나 약어형태의 영어원어가 신문에서는 약 $82\%$를 차지하기 때문에 이를 처리할 방법이 필요하다. 따라서 본 논문에서는 바이그램을 기본으로 하는 형태정보를 이용하여 적합대역어를 선정하고 이와 형태정보를 공유하는 한국어대역어쌍들을 군집화한다. 또한, 음차표기어와 두문자어에 대한 처리를 추가하여 적용범위를 넓힌다. 실험을 위하여 신문말뭉치에서 추출한 대역어쌍 1,806개 중 영어원어를 기준으로 한국어대역어의 수가 5개 이상인 대역어쌍 집합 200개를 선정하였다. 본 논문에서 제시한 방법으로 측정한 결과, 대역어 군집화에 대해서는 $74\%$의 정확율과 $65\%$의 재현율을, 적합대역어 선정에 대해서는 $97\%$의 정확율을 보였다.

• Annual Conference of KIPS
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• 2004.05a
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• pp.727-730
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• 2004

영상은 복잡한 객체들의 집합으로 이루어져 있기 때문에 영상에 포함된 객체를 분리하는 일은 컴퓨터 비전이나 인식 등 많은 분야에서 중요시 된다. 영상 처리 측면에서 객체를 분할하기 위해서 색상, 모양, 질감, 움직임 등 다양한 기법들이 이용되고 있다. 본 논문에서는 정확한 색상의 비교를 위해서 CIE 색상 모델을 이용하고 있으며 이것을 기반으로 객체를 추출하고 있다. 그리고 추출된 객체의 해석과 검증을 위해서 모양 기반의 분석법을 이용하고 있다. 본 논문에서는 Pan/Tilt 카메라의 타겟팅(Targeting)과 포커싱(Focusing)을 위해 영상 내에 포함되어진 객체를 검출하기 위한 방법론을 제안하고자 한다. 객체를 인식하기 위해 CIE 색상 모델을 이용한 색상 매칭 기법을 제안하고 있다. 색상의 분포를 파악하기 위해서 CIE 모델이 생성해내는 Lab 블록을 통계적인 방법으로 분석한다. 그리고 분석된 결과는 CIE 블록 매칭(Bock Matching) 기법의 기준이 되며 이것을 이용해서 후보 객체 영역(Candidate Object Area)을 추출하게 된다. 추출된 후보 객체 영역을 검증하기 위해서 모멘트를 이용한 모양 기반의 분석을 활용하고 있다.