• 제목/요약/키워드: delineated

검색결과 419건 처리시간 0.025초

Micro and macro in the dynamics of dilute polymer solutions: Convergence of theory with experiment

  • Prakash, J. Ravi
    • Korea-Australia Rheology Journal
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    • 제21권4호
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    • pp.245-268
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    • 2009
  • Recent developments in dilute polymer solution rheology are reviewed, and placed within the context of the general goals of predicting the complex flow of complex fluids. In particular, the interplay between the use of polymer kinetic theory and continuum mechanics to advance the microscopic and the macroscopic description, respectively, of dilute polymer solution rheology is delineated. The insight that can be gained into the origins of the high Weissenberg number problem through an analysis of the configurational changes undergone by a single molecule at various locations in the flow domain is discussed in the context of flow around a cylinder confined between flat plates. The significant role played by hydrodynamic interactions as the source of much of the richness of the observed rheological behaviour of dilute polymer solutions is highlighted, and the methods by which this phenomenon can be incorporated into a macroscopic description through the use of closure approximations and multi scale simulations is discussed.

미국 뉴욕시 서포티브주택 '더 크리스토퍼' 현장분석 연구 (A Field Study of Supportive Housing 'The Christopher' in New York, USA)

  • 이연숙;박재현
    • 한국주거학회논문집
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    • 제26권1호
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    • pp.19-30
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    • 2015
  • As the number of homeless is increasing, there have been worries for social burden and social insecurity, along with crisis in human dignity. The purpose of this research is to identify characteristics of a Supportive Housing (SH) project which is considered best practice in dealing with homeless problem. A field visit walk through observation and in-depth interview was utilized as the main research method. As results, overall management, spatial and service characteristics were delineated, and its meaning and uniqueness were discussed, as well as, comparison with Korean conditions. In conclusion, the characteristics of the Supportive Housing were more realistically revealed through a current field case to inspire to explore housing for Korea. Besides current concerns were linked and implication to Korean adaptation was suggested. This study is unique in that SH of USA is firstly introduced in such details.

거주자 생활사례분석을 통해 본 도시한옥의 생태성에 관한 연구 (Ecological Design Characteristics of Urban Traditional Housing Through Residents' Living Experiences)

  • 조성진;이연숙;최령
    • KIEAE Journal
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    • 제4권3호
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    • pp.143-152
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    • 2004
  • The purpose of this study was to systematize space composition characteristics of urban traditional housing in Bukchon area. Out of 924 existing houses, 106 houses were selected and analyzed based on availability of documents and its function as pure residential living. According to which major rooms were changed, six categorizes were delineated as follows : unchanged type, type with changed Anbang, type with changed Gunnunbang, type with changed Aratbang, type with changed Daichung and totally changed type. Characteristics of each type were systematically analyzed and described. The results showed how traditional culture and contemporary lifestyle coexisted and were integrated.

Effect of $Mo_2C$ Content on the Microstructure and Properties of Ti(CN)-$Mo_2C$ Ceramics

  • Park, Dong-Soo;Lee, Yang-Doo;Taejoo Jung
    • The Korean Journal of Ceramics
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    • 제5권3호
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    • pp.230-234
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    • 1999
  • Ti(CN)-0.3mole% $Mo_2C$ ceramics were prepared by pressureless sintering. $Mo_2C$ dissolved in Ti(CN) more easily in a nitrogen environment than in the other environment because nitrogen forced Mo to form a solid solution, (Ti, No)(C, N). A "core-rim" structure developed within the grains. The boundary between the "core" and the rim was delineated by thermal etching in the sample with more than 2 mole% $Mo_2C$. The rim thickness and the grain size decreased as the $Mo_2C$ content increased. The hardness and the flexural strength showed maxima of 18.2 GPa and 1.23 GPa, respectively when the $Mo_2C$ content was 2 mole%. The post-sintering heat treatments improved the properties.oved the properties.

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좌심실을 통한 관상동맥 우회술의 평가를 위한 관상순환계의 수치적 모델 (Computational modeling of the coronary circulation for the assessment of the coronary artery bypass through left ventricle)

  • 심은보
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집B
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    • pp.385-390
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    • 2000
  • In this study we propose the computational model for the coronary circulation. The bypass from left ventricle is also considered. Lumped parameter model with three compartments in the coronary circulation is implemented in this study. We connected the coronary artery compartment with left ventricle to explain the bypass procedure from left ventricle. The asymmetric resistance is assumed in the bypass line from left ventricle. The present numerical method is tested for normal coronary circulation and the results are compared with the existing computational work. The bypass simulation is conducted and the flow pattern is delineated. The effect of shunt resistance and coronary compliance to circulation is investigated for the better design of the bypass shunt.

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″Drifting Cups on a Meandering Stream″in Korea

  • Chang, Keun-Shik
    • Journal of Mechanical Science and Technology
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    • 제15권12호
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    • pp.1762-1767
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    • 2001
  • The Posuk-Chung Pavilion if a defunct irregular stone water channel in Kyongju, Korea, once used for the meandering stream feast'by kings of Silla Dynasty during the first millennium. The poets were seated around this stone water channel who composed the Chinese poems, overlooking the streams. They load to take the punishment drinks unless they finished the poem before the drifting cup filled with the rice wine arrived at their seats on the meandering stream. In this paper, we have made computer simulation as well as well as model experiment on the ancient meandering stream of the Posuk-Chung Pavilion. The computational results are compared with the experiment and the channel flow characteristics are delineated here. It is discussed how the present Posuk-Chung channel is morphologically distinguished from the Chinese and Japanese meandering streams.

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전자빔 리토그라피에서 스트링모델을 이용한 3차원 리지스트 프로파일 시뮬레이션 (3-D resist profile simulation using string model on E-beam lithography)

  • 서태원;함영목;전국진;이종덕
    • 전자공학회논문지A
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    • 제33A권6호
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    • pp.144-150
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    • 1996
  • The purpose of this paper is to develop a simulation program to predict resist prifile in electron-beam lithography, where the main issue is proximity effect. The simualtion program composes of monte-carlo simulation, exposure simulation and development simulation. In nonte-carlo simulation, the absorbed energy in the resist is calculated when one electron is incident into resist, using hybrid model on the basis of the rutherford differential scattering cross section and moller theory. In exposure simulation, the absorbed energy in the resist is calculated when electrons are incident in exposure pattern. In the program, the developed profile depending on time is obtained by string model. The 0.2$\mu$m and the 0.3$\mu$m line and space patterns are experimentally delineated and compared to the simulation results to check the relevance of the program.

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2,3-Dihydropyrrolo[1,2-b]benzisothiazole 5,5-Dioxide들의 비대칭성 광이성질화 반응 (A New Asymmetric Photoisomerization of 2,3-Dihydropyrrolo[1,2-b]benzisothiazole 5,5-Dioxides)

  • Elghamry, Ibrahim;Dopp, Dietrich
    • 대한화학회지
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    • 제54권6호
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    • pp.727-730
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    • 2010
  • 245 nm mercury lamp를 사용하여 2,3-dihydropyrrolo[1,2-b]benzisothiazole 5,5-dioxide를 광이성질화 반응시켜서 2,3-dihydro[1]benzothieno[3,2-b]pyrrole 4,4-dioxide를 가지고 있는 tricyclic ring system 화합물을 합성하는 방법을 개발하였다. 합성한 화합물들에 대한 구조는 IR, NMR, MS 및 single crystal X-ray crystallography를 이용하여 결정하였다.

Analysis of Supply Airflow Control by a Stratified Thermal Model in a VAV System

  • Kim, Seo-Young;Moon, Jeong-Woo;Cho, Hyung-Hee
    • International Journal of Air-Conditioning and Refrigeration
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    • 제9권3호
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    • pp.46-56
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    • 2001
  • The present study concerns the numerical simulation of a supply airflow control in a variable air volume (VAY) system. A stratified thermal model (multi-zone model) is suggested to predict a local thermal response of an air-conditioned space. The effects of various thermal parameters such as the cooling system capacity, the thermal mass of an air-conditioned space, the time delay of thermal effect, and the building envelope heat transmission are investigated. Further, the influence of control parameters such as the supply air temperature, the PI control factor and the thermostat location on a VAV system is quantitatively delineated. The results obtained show that the previous homogeneous lumped thermal model (single zone model) may overestimate the time taken to the set point temperature. It is also found that there exist the appropriate ranges of the control parameters for the optimal airflow control of the VAV system.

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성층화 열용량 모델을 이용한 VAV 시스템 급기 제어 시뮬레이션 (Simulation of Supply Air Control in a VAV System Using a Stratified Lumped Thermal Model)

  • 문정우;김서영;김원년;조형희
    • 설비공학논문집
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    • 제12권7호
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    • pp.632-641
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    • 2000
  • The present study concerns the simulation of supply-air control in a variable air volume (VAV) system. A stratified lumped thermal model (multi-zone model) is suggested to predict local thermal response of an air-conditioned space. The effects of various thermal parameters such as the cooling system capacity, the thermal mass of air-conditioned space, the time delay of thermal effect, and the building envelope heat transmission are investigated in detail. Further, the influence of control parameters, PI control factor and the sensor location on a VAV system is quantitatively delineated. The results obtained show that the previous homogeneous lumped thermal model (1-zone model) may predict a significantly different thermal response in the air-conditioned space according to the sensor location.

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