• Title/Summary/Keyword: 사이중심도

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Rib-Dimple Compound Cooling Techniques in a Gas Turbine Blade Cooling Channels with an Aspect ratio (4:1) (4:1 종횡비를 갖는 가스터빈 블레이드 냉각 유로에서의 립-딤플 복합 냉각 특성 연구)

  • Choi, Yong-Duck;Kim, Seok-Beom;Lee, Yong-Jin;Kim, Jin-Kon;Kwak, Jae-Su
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.05a
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    • pp.304-310
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    • 2010
  • Heat transfer coefficients in a dimpled channel, a ribbed channel, and a rip-dimple compound channel were measured by the transient liquid crystal technique. The channel aspect ratio, the rib height, the rip pitch, and the rib angle were 4:1, 6 mm, 60 mm and $60^{\circ}$, respectively. The dimple diameter and the center-to-center distance were 6mm and 7.2 mm, respectively, and the Reynolds number range was 30,000-50,000. Results showed that the heat transfer coefficients were increased by the angled rib. For the dimple-rib compound cooling cases, the heat transfer coefficients were further augmented and the thermal performance factor for the case was the highest.

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Forecasting for the Demand on Water Amenity Zones in the Large Rivers Based on Regional Characteristics and Monthly Variation (지역 특성 및 월간 변화를 고려한 대하천 수변 친수지구 이용수요 예측)

  • Suh, Myong-kyo;Rhee, Dong Sop
    • Journal of Wetlands Research
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    • v.17 no.4
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    • pp.436-446
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    • 2015
  • It is suggested investigating method about the existing state of demand in this study. The total demand of 357 water amenity zones in 2014 is estimated based on the growth curve models. The effects of population density and distances between water amenity zones and metropolises populated over 1 million are investigated on each river system. The suitability like RMSE and MAPE of logistic and gompertz models are considered to select more suitable model for each water amenity zone. Demand for water amenity zones in 2014 is seemed to be rather high at Han Gang river system and Chungcheongbukdo after analyzing. The influence of population density is rarely effective except Geum Gang river system. The influence of metropolis on the demand for water amenity zones is higher at Geum Gang river system than others.

Water Resources Assessment of the North Han River Watershed Using the DPSIR Concept (DPSIR 개념을 이용한 북한강 유역의 수자원 평가)

  • Lee, Kil-Seong;Sung, Jin-Young;Chung, Eun-Sung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.813-816
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    • 2010
  • 최근 지속가능한 개발의 개념은 국제적으로 경제 개발과 환경 보전 사이에서 논쟁이 중심이 되고 있으며, 수자원 개발과 관리는 이들 논쟁에서 중요한 부분을 차지하고 있다. 이와 더불어 유역을 관리함에 있어 수자원을 이수, 치수 및 수질의 단일 문제로 인식하는 것이 아니라 통합적으로 인식하는 유역통합관리(Integrated Watershed Management, IWM)의 필요성이 대두되고 있다. 이에 본 연구는 유역통합관리에 앞서 유역의 상태 및 문제점을 파악하기 위한 방법으로 EEA (European Environment Agency)에서 개발한 추진력(Driving force)-압력(Pressure)-상태(State)-영향(Impact)-반응(Response) (DPSIR) 개념 이용하여 3개의 세부 지표인 이수지표, 치수지표, 수질지표로 구성된 하나의 통합 지수인 유역수자원평가지수를 개발하였다. 세부지표인 이수지표는 연속무강우일수, 인구밀도, 용수수요, 물재이용률 등 16개의 구성요소, 치수지표는 홍수범람위험 지역 내 거주 인구수, 홍수방어시설용량, 개수율, 100 mm 이상 강수일수 등 15개의 구성요소, 수질지표는 BOD (Biochemical Oxygen Demend) 부하량, 수질 등급, 연중 목표 수질 달성일수 등 13개의 구성요소로 이루어져있다. 이를 북한강 유역 중 북한 지역을 제외한 유역 즉, 수자원단위지도 상의 춘천댐권역(1010) ~ 청평댐권역(1015)의 6개 중권역에 적용하여 비교하였다. 세부지표의 주된 요소인 유출량의 모의를 위해 장기유출모형인 HSPF (Hydrological Simulation Program - Fortran)를 사용하였다. 모형에 입력된 유역평균강수량 자료는 1973년 ~ 2008년까지의 37년의 자료기간을 갖는 북한강유역의 5개 기상관측소 자료를 Thiessen network를 이용하여 산정하였다. 본 연구를 통해서 북한강 유역의 현재 수자원의 상태를 지수화하여 나타내고 그 결과를 비교해보았다. 이 결과는 유역 수자원의 파악하여 유역통합관리시 유역의 문제점을 파악하고 이를 수정하기 위한 의사결정 우선순위를 정하는데 사용될 수 있다.

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Mode-Design, auf erotischer Expressions Ebene (에로티시즘표현의 의상디자인에 관하여)

  • Yang, Ri-Na
    • The Journal of Natural Sciences
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    • v.6 no.1
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    • pp.89-102
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    • 1993
  • Das ursprngliche menshiche Verlangen nach Erotik hatte trotz der Unterdruckung und des Verbots seit der Anfang der Zeit bis heute stets das menschliche Interesse auf sich gezogen. Diese Erotik drckte nicht nur die knstlerische Handlung aus, sondern sie hat auch eine enge Beziehung zur kubischen Darstellung von Mode. Sie beschreibt die innere menschliche Welt und ist der Motor der individuellen Mode. Die Erotik entsteht wesentlich aus der Tiefe der menschlichen Psyche, ist sowohl erzeugende und starke schpferische Krfte als auch der Antrieb zur Annhrung der unsterblichen Welt. Darberhinaus ist sie auch der Wunsch jedes Individums, sich selbst zu entdecken. Diese Erotik beruht sich in unserem Unterbewutsein und Sie bricht nur dann aus, wenn der Mensch von der rtselhaften Leidenschaft beherrscht wird. Dardurch werden gewisse Krfte frei und sie motivieren den Menschen durch verschieden knstlerische Darstellung diese Erotik auszudrcken. Dieser ganz natrliche Ausdruck menschlicher Begierde wurde durch Kleidung nach Auen signalisiert. Damit drckte der Mensch seine Individualitt aus, und versuchte sich den anderen gegenber so reizvoll wie mglich zu zeigen und wirkte sehr anziehend. Schlilich hat er sich als Sex-Appeal zur Schau gestellt. Solches menschliche Sehnsucht nach Erotik wurde seit dem Altertum bis heute durch verschiedene erotische Kieidungen zum Ausdruck gerbracht.

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Measurement and Analysis of the Structure by Using the Terrestrial Camera (지상실체사진기를 이용한 구조물의 측정과 해석)

  • 안철호
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.2 no.1
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    • pp.54-64
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    • 1984
  • This paper is a study on structural measurement by using a terrestrial camera. The aim of this paper is to understand the method of a composition by analyzing the geometrical compositive ratio of threestoried pagodas at Gamun-Sa, Gosun-Sa, Bulguk-Sa, Seated iron Buddha in Kwang-Jn, and Main-Seat Buddha at Sukkuram Cave-temple. Measured data and contour maps are accurately obtained by means of photogrammetry, and the following points are able to he found by analyzing them. At first, for Stone Pagodas. the breaths of the Okgesuks are made to the ratio, 8 : 7 : 6. And when an equililateral triangle and an 45$^{\circ}$ isosceles triangle are drawn of which the bases are the length of the upper Gabsuk, and then a circle is drawn whose radius is the length between the vertexes of the two triangles and its center is the vertex of the former the circle passes the upper line of the third Oksin. Also it can be found that an $70^{\circ}$ isosceles triangle being drawn at base line, the triangle passes the edge point of the upper Gabsuk and the center of the third Okgesuk. Also for Budha statues, it can be found that circles whose center is that of eyes can be drawn, and if 2 lines which pass the shoulder and the center of Buddha's body are extended, they intersect the knees.

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The Comparison and Analysis of Models on Ratio and Rate in Elementary Mathematics Textbooks : Centering on Multiplicative Perspectives on Proportional Relationships and the Structure of Proportion Situations (초등 수학 교과서 비와 비율 단원의 모델 비교 분석 -비례에 대한 곱셈적 사고 및 비례 상황의 구조를 중심으로)

  • Park, Sun Young;Lee, Kwangho
    • Education of Primary School Mathematics
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    • v.21 no.2
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    • pp.237-260
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    • 2018
  • This study investigated the models of four countries' elementary mathematics textbooks in Ratio and Rate and identified how multiplicative perspectives on proportional relationships and the structure of proportion situations are reflected in the textbooks. For this, textbooks of 5th and 6th grade textbooks in Korea Japan, Singapore and U.S. are compared and analyzed. As a result, we can find multiplicative perspectives on proportional relationships and the structure of proportion situations on pictorial models, ratio tables, double number lines and double tape diagrams. Also, the development of Japanese textbooks from multiple batches perspectives to variable parts perspectives and the examples of the use with two models together implied the connection and union of two multiplicative perspectives. Based on these results, careful verification and discussion for the next textbook is needed to develop students' proportional reasoning and teach some effective reasoning strategies. And this study will provide the implication for what kinds of and how visual models are presented in the next textbook.

Effect of the Urban Land Cover Types on the Surface Temperature: Case Study of Ilsan New City (도시지역의 토지피복유형이 지표면온도에 미치는 영향: 경기도 일산 신도시를 중심으로)

  • Kim, Hyun-Ok;Yeom, Jong-Min
    • Korean Journal of Remote Sensing
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    • v.28 no.2
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    • pp.203-214
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    • 2012
  • The physical environment of urban areas covered mostly by concrete and asphalt is the main cause of the urban heat island effect, primarily becoming apparent through increased land surface temperature. This study examined the effect of different urban land cover types on the land surface temperature using MODIS, Landsat ETM+ and RapidEye satellite data. As a result, the remote sensing based land surface temperature showed a marked difference according to the land use pattern in the case study of Ilsan new city. The high-rise apartment residential districts with less building-to-land ratio and higher green area ratio revealed lower land surface temperature than the low-story single-family housing districts characterized by relatively high building-to-land ratio and low green area ratio. From the view of climate zone and land cover types, there is a strong linear correlation between the impervious land cover ratio and the land surface temperature; the land surface temperature increases as the impervious built-up areas expand. In contrast, vegetation;water and shadow areas affect the decrease of land surface temperature. There is also a negative (-) correlation between NDVI and land surface temperature but the seasonal variation of NDVI can be hardly corrected.

A Spatial Analysis of Research Collaboration by Using Co-authorship Publications (공동저술 논문을 이용한 연구협력에 대한 공간적 분석)

  • Beck, Yeong Ki
    • Journal of the Korean Geographical Society
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    • v.50 no.6
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    • pp.641-657
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    • 2015
  • Nowadays research collaboration between the business, academic and governmental community is high on the policy agenda in all over the world, especially with regard to science-based technological innovation. The aim of this paper is to explore some of the changing spatial patterns of research collaboration by carrying out bibliometric analysis of co-authorship publications in major international and scientific journals that are jointly realized by Korean scientists and researchers in the seven science-based technologies for the period 2002~2012. Using the co-authored papers as an indicator of research collaboration with the institutional address of each co-authoring researcher and the geographic location of their affiliation, this paper describes some trends and patterns of domestic and international research collaborations. Identifying a rapid increase in the volume of co-authored papers and the trend towards multiple authorships over the last decade, the paper finds collaborative scientific research to be geographically dispersed at the different spatial scales. Despite the rising geographic dispersion of research collaboration within the nation, this paper finds that there were empirical evidences for the presence of localized knowledge production processes at regional level, and biased knowledge flows towards core areas with advanced research resources.

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Facebook Fatigue: Narcissism, Reputation Concern, and Expectation of Others' Responses (페이스북 피로감에 대한 연구: 자기애, 평판근심, 반응기대를 중심으로)

  • Lee, Jongmin;Lee, Jihye;Sung, Yongjun
    • Journal of the HCI Society of Korea
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    • v.13 no.3
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    • pp.35-42
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    • 2018
  • Social Networking Sites (hereafter SNSs) have become a part of people's daily routines. Beginning as a hobby/communicating tool for a specific group of people, SNSs have expanded in terms of the number of users, frequency of access, and depth and range of sharing. It is recently reported that the users experience SNS fatigue from being connected at all time. However, limited research has addressed this issue. The purpose of the present study was to examine the mediating role of reputational concern and expectation of others' responses on the relationship between narcissism and Facebook fatigue. A total of 329 Facebook users completed an online survey. The results showed that individuals who rated high on narcissism experienced a high level of Facebook fatigue, and that both reputational concern and expectation of others' responses partially mediated the relationship between narcissism and fatigue. Implications of the findings and suggestions for future research are discussed.

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Analysis of Load Capacity and Deformation Behavior of Suction Pile Installed in Sand (모래지반에 근입된 석션파일의 인발저항력 및 변위거동 분석)

  • Kim, You-Seok;Jang, Yeon-Soo
    • Journal of the Korean Geotechnical Society
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    • v.27 no.11
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    • pp.27-37
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    • 2011
  • A series of centrifuge model tests to investigate the suction pile pullout loading capacity in sand have been performed. The main parameters that affect the pullout loading capacity of a suction pile include the mooring line inclination angle and the padeye position of the suction pile. With respect to the padeye position, the maximum pullout loading capacity is obtained when the padeye position is near 75% of the pile length from the top. The direction of the pile rotation changes when the padeye position reaches somewhere near 50~75% for all mooring line inclination angles. The translation displacement of suction pile to develop the time of maximum pullout loading capacity decreased as the mooring line inclination angle increased. In addition, the vertical displacements of the center of a suction piles for all cases appeared to develop toward the ground surface.