• Korea-Australia Rheology Journal
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• 제21권4호
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• pp.213-223
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• 2009

Taylor-Couette flow (i.e., flow between concentric, rotating cylinders) has long served as a paradigm for studies of hydrodynamic stability. For Newtonian fluids, the rich cascade of transitions from laminar, Couette flow to turbulent flow occurs through a set of well-characterized flow states (Taylor Vortex Flow, wavy Taylor vortices, modulated wavy vortices, etc.) that depend on the Reynolds numbers of both the inner and outer cylinders ($Re_i$ and $Re_o$). While extensive work has been done on (a) the effects of weak viscoelasticity on the first few transitions for $Re_o=0$ and (b) the effects of strong viscoelasticity in the limit of vanishing inertia ($Re_i$ and $Re_o$ both vanishing), the viscoelastic Taylor-Couette problem presents an enormous parameter space, much of which remains completely unexplored. Here we describe our recent experimental efforts to examine the effects of drag reducing polymers on the complete range of flow states observed in the Taylor-Couette problem. Of particular importance in the present work is 1) the rheological characterization of the test solutions via both shear and extensional (CaBER) rheometry, 2) the wide range of parameters examined, including $Re_i$, $Re_o$ and Elasticity number E1, and 3) the use of a consistent, conservative protocol for accessing flow states. We hope that by examining the stability changes for each flow state, we may gain insights into the importance of particular coherent structures in drag reduction, identify simple ways of screening new drag reducing additives, and improve our understanding of the mechanism of drag reduction.

• 건축역사연구
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• 제13권3호
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• pp.51-67
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• 2004

The purpose of this study is to bring light on the characteristics of the transition in the Ddeulzip. The subject of this study is clan village of Pungsan Kim's family in Andong Cultural Area. Architectural transition of Ddeulzip is analyzed into three part. The first part is settlement of family. In this process, there is a background and many types of settlement. The second part is the extension of family. The extensional types are 'near-by branch' and 'far-away branch'. The last part is variation of housing. Spacial requests of residence are changed endlessly. Thus the spacial types of Ddeulzip are changed by the construction time of building. In many case, we couldn't decide the building period. The genealogy of Chosun Dynasty is the base of family history. In this study, the construction activity of Ddeulzip is based on the genealogy. The phylogenetic tree of Ddeulzip in clan village is constructed by the genealogy. The figures of the type of bunch of grapes is made by phylogenetic tree based on the genealogy. Omi Village in Andong was settled at first in the 15C. The cause of settlement is the aim of escape from political oppression. For long time, Omi Village is developed gradually. There area is divided in some small family boundary. There spacial types are contained the characteristics of many times. Orock Village in Bonghwa is settled for search of best environment in the last of 17C. At that time, a lot of families of same clan are gathered in that village. For short time, Orock Village is enlarged quickly. Thus there spacial type is similar each other. But boundary of entire space of outdoor is constructed clearly by pavilion area, housing area and sanctuary area.

• 수산경영론집
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• 제22권1호
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• pp.1-52
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• 1991

This study deals with the evolutional history of the holding and utilization of fisheries resources in Korea. Fisheries resources have the basic characteristics of the density dependent self-regulating renewable and common property resources, Irrational utilization of fisheries resources is mainly due to the unlimited access to the resources. The holding and utilization of fisheries resources in Koryo era was opened to everyone. But it was nationalized in the early Yi Dynasty. The purpose of its nationalization was to provent the paticular powered-man with their monoplized holding and to levy fisheries tax. Eoeop-peop, the first modern fisheries law in Korea, was enacted as a part of the invasion policy of Japan in 1908. With the japanese annexation of Korea in 1910, the Japanese Government established a new institutional system of fisheries as a part of an overall reformation of the institutional for an implementation of the colonial policy. It was very the new enacted Fisheries Law (Gyogyorei). Also the Government enacted compulsorily another new Fisheries Law (Chosen Gyogyorei) with its adjunct laws and regulations revise the institutional system of fisheries on May 1, 1930. After Eoeop-peop enactment, the fisheries resources in Korea could be used only under the license, permission, and statement. After Korea was from Japan in 1945, Korea Government at last enacted the new fisheries law (Susaneop-peop) in 1953. The goal of Susaneop-peop was to achive the general usage and protection of the fisheries resources, and to attain the development and democratization of the fishery in Korea. This law was amended 13 times until 1990. The license fishery have a legal right on the fishery, called a fishery rigt. This right means a right of exclusive occupation and utilization of a unit of the inshore fishing grounds. The main evolutional issues of license fishery are as the following : 1) the foundation of the exclusive usable fishery right(1911, Gyogyorei), 2) the deletion of the settled U9space lift net and settled space sein net fishery, and the expansion of the cooperative fishery-No.1, 2, and 3 type cooperative fishery-(3rd amendment, 1963), 3) the deletion of the No.2 and 3 type cooperative fishery, and the separation of the culturing fishery in No.1 and 2 type culturing fishery (13th amendment, 1990). The effective period of the license fishery was amended as the following : 1) 1908(Eoeop-peop) : within 10 years, renovation system, 2) 1929(Chosen Gyogyorei) : within 10 years, unlimited extension system, 3) 1971. 7th amendment : 10 years, renovation system, 4) 1972. 8th amendment : 10 years, only 1 extension system, 5) 1975. 9th amendment : 5-10 years, only 1 extension system, 6) 1990.13th amendment : 10 years, within 10 years of total extensional years. The priority order of the fishery license was established in 1953 (Susaneop-peop). The amendment of it is as follows : 1) 1953. enactment \circled1 the fishing grounds that the fishery right is extablished 1st order : the existing fishery right man, unlimited renovation 2nd order : the corporate that the regional fisherfolk organized 3rd order : the rest experienced fishermen \circled2 new fishing grounds 1st order : the corporate that the regional fisherfolk organized 2nd order : the rest experienced fishermen 2) 1971. 9th amendment \circled1 the fishing grounds that the fishery right is established 1st order : the existing fishery right man, unlimited renovation 2nd order : the Eochongye that the regional fisherfolk organized 3rd order : the regional fishery cooperative that the regional fisherfolk organized 4th order : the rest experienced fishermen \circled2 new fishing grounds 1st order : the Eochongye that the regional fisherfolk organized 2nd order : the regional fishery cooperative that the regional fisherfolk organized 3rd order : the rest experienced fishermen 3) 1981. 10th amendment \circled1 the inside of No.1 type cooperative fishing grounds 1st order : the Eochongye that the regional fisherfolk organized 2nd order : the regional fishery cooperative that the regional fisherfolk organized 3rd orer : the rest experienced fishermen 4) 1990. 13th amendment \circled1 No.1 type cultural fishery 1st order : the Eochongye that the regional fisherfolk organized 2nd order : the regional fishery cooperative that the regional fisherfolk organized 3rd order : the rest experienced fishermen \circled2 No.2 type cultural and settle fisher : general priority order The effective period of the permission fishery was amended 6 timed. First, it was within 5 years and renovation system (Eoeop-peop). Now it is 5 years and renovation system. The effective period of the statement fishery was amended 4 times. First, it was within 5 years, and then was amended within 3 years(Chonsen Gyogyorei). Now it is 5 years.

• 자원환경지질
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• 제39권2호
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• pp.163-171
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• 2006

본 연구는 단열지질조사를 통한 대상지역의 지하수 단열 모델을 규명하여 지하수를 개발한 사례이다. 경기도 문산 동쪽에 위치하고 있는 산업시설물에서는 시설물 유지에 필요한 용수 수급용 지하수개발이 요구되었다. 지하수 개발 대상 지역은 $0.15Km^2$ 면적으로 제한되어 있었을 뿐만 아니라, 지하 매설물, 건물 등의 시설물을 피하여 선정, 개발해야 되는 매우 어려운 지리적 조건을 가지고 있었다. 지하수 개발 대상지역은 지하 매설물이 설치되어 있어 지구물리탐사가 불가한 곳으로 지질조사에만 의존하여 지하수개발을 수행하였다. 편마암의 엽리와 암상조사로 엽리 궤적도를 작성하며 조사대상지역에 발달하고 있는 남북방향 습곡축의 향사형 습곡이 인지되었다. 동서방향의 지질단면 분석에서는 아이스크림 스푼 모양의 F2 향사형 중첩습곡이 해석된다. 광역조사에서 인지된 $N20^{\circ}E,\;N30^{\circ}W$, NS 주향의 단층연장 상에 위치하는 평평한 조사대상지역에 수반성 인장단열들의 존재 가능성을 예측하였다. 우수향 운동감각을 갖고 있는 $N20^{\circ}E$ 단층 은 F2 향사형 습곡에 발달하고 있는 두 조의 요곡성 공액형인 P-전단단층으로 해석된다. NE 주향 지질단면상에서, $N20^{\circ}E$ 단층과 엽리 간의 교각으로 약 100m 심도에서 지하수저장이 가능한 삼각 프리즘형태의 공간형성이 가능함을 알 수 있어, 중첩습곡의 서쪽 날개 쪽이 지하수개발 가능지역으로 예측하였다 또한 $N40^{\circ}E$ 단층도 지하수공급원이 될 수 있다. 단열지질조사와 단면해석을 기초로 하여 $N20^{\circ}E$와 $N40^{\circ}E$ 단층을 따라서 지하수 개발가능 위치를 선정하였으며, $N20^{\circ}E$ 단층선 상에 위치한 한 지점을 선정한 결과 이곳에서 145 ton/day의 지하수를 개발하였다. 결론적으로 개발에 성공한 지하수는 중첩습곡에 수반된 요곡단층과 엽리 교차로 형성된 지하수 저장고의 불투수 공간으로부터 공급된 것으로 해석되었다.