• Title/Summary/Keyword: :Layered Flow

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Removal Efficiency of PM10 & $CO_2$ in Subway Mock-up Cabin (지하철 목업차량내 객실 공기정화장치의 미세먼지(PM10) 및 $CO_2$ 저감성능평가)

  • Kwon, Soon-Bark;Park, Duck-Shin;Cho, Young-Min;Kim, Jong-Bum;Cho, Goan-Hyun;Nam, Goong-Seok;Lee, Joo-Yeol;Kim, Tae-Sung
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.613-618
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    • 2011
  • More than 7 million persons use Seoul Metropolitan Subways (SMS) everyday and the number has been in increasing trend. With the increasing trend of concerns on indoor air quality(IAQ), the management of IAQ has become an important issue, especially in case of subway operators, because most of subway lines are placed underground with poor ventilation condition. The ultimate object of study develop independent cleaning device that reduce efficient fine particle and $CO_2$. Urban subway has characteristics about proper clean air flow, must be installed in narrow space and maintenance cycle has enough time. Two layered electrically pre-charged filters were used for removing particulate matters and gas absorbers are packed between two layer filters for removing gases pollutants such $CO_2$, VOCs and HCHO. Urban subway has characteristics about proper clean air flow, must be installed in narrow space and maintenance cycle has enough time. SCAP prototype is producted as all in one method which decrease fine dust, $CO_2$ and noxious gas. and basic test carry out with quantity of wind, a gap of pressure, sampling efficiency.

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A Study on the Baroque Characteristics Expressed in Architecture by Richard Meier (리처드 마이어 건축에 표현된 바로크적 특성 연구)

  • Han, Myoung-Sik
    • Korean Institute of Interior Design Journal
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    • v.22 no.3
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    • pp.127-134
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    • 2013
  • Baroque is fundamentally in contrast with renaissance style classicism, which attempted to fix a world view itself as the value of perpetuity. Furthermore, it is interpreted as a topic of incompletion or transformation that is not defined or is not exemplary and which may be enjoyed by people in the classical life, which requires a microscopic concept in contrast with dualism, the central axis of western civilization, namely, rational lucidity. Also, such characteristics are estimated to serve as a lubricant in life while going beyond the formal aesthetic level of art even from a contemporary perspective, and to play a productive role and to have potential. Consequently, this paper assumed that the concepts expressed by the 20th century US contemporary architect Richard Meier of a complex space, namely architectural formative vocabularies such as overlapping, interpenetration, collision, and collage style mixture created by a layered structure, in his architecture are in common with the double surface technique and juxtaposition of a flat structure of Baroque architecture. Then, the paper analyzed and considered the characteristics. The paper considered the following two issues: Such Baroque style formal principle is reinterpreted against a backdrop in which his architectural flow based on the domino theory of Le Corbusier became established as his own unique architectural feature, and it may be proposed as one big flow that enables us to seek again modernistic architecture that attempts to make an architectural space absolute as an atypical formal contour.

Numerical study of double diffusive convection due to lateral heating in a rotating annulus (회전하는 환형용기내의 옆면 가열에 의한 이중확산대류에 관한 수치해석)

  • Gang, Sin-Hyeong;Lee, Gyo-Seung;Lee, Jin-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.11
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    • pp.1422-1436
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    • 1997
  • Numerical investigations were conducted to study the convective phenomena of an initially stably stratified salt water solution with lateral heating in a uniformly rotating annulus. The method of investigation is the finite difference analysis of the basic conservation equation for an axisymmetric, unsteady, double-diffusive convection and calculation is made for R $a_{\eta}$=2*10$^{5}$ and Ta=10$^{7}$ ~ 2.5*10$^{8}$ . Formation of layered flow structure, merging process of layers, the corresponding temperature and concentration distributions, Nu variation with time are examined. Numerical results show that in each layer, the temperature profile looks 'S'-shaped and the concentration profile is uniform due to the convective mixing. At the interface between adjacent layers, the temperature changes smoothly but the concentration changes rapidly. As the effect of the rotation increases, the generation of rolls at hot wall, the formation and merging of layers are delayed. The average Nu shows the trend of conduction heat transferees the effect of the rotation increases.n increases.

IMPROVEMENT OF FRESHENING PROCESS BY MEANS OF UNDERDRAINAGE CONDUIT

  • Suh, Young-Jea;Kim, Jin-Kyoo
    • Korean Journal of Hydrosciences
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    • v.4
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    • pp.93-104
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    • 1993
  • This paper is concerned with the actual comparison analysis for the freshening process in the two selected experimental reservoirs. At the deep freshening reservoir, salinity and depth of the freshwater layer were estimated by simulation technique using the quantitative equation for the two layered flow structures. First of all, it is shown that the effects of underdraiange conduit in the lower layer were reported more effective for the control of upper layer salinity comparing with the case of no underdraiange conduit. Further the results of computation were later compared with the real observed values and the relating parameters of the salt balance equation are conformed even though approximately. Finally it was represented that the salinity of upper layer is easily diluted not only by the tidal gate but also by the underdraiange conduit in the lower layer of the freshening reservoir.

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An Analysis of Cone Penetration Based on Arbitrary Larangian-Eulerian Method (Arbitrary Lagrangian-Eulerian 기법에 의거한 콘 관입 해석)

  • Oh, Se-Boong
    • Journal of the Korean Geotechnical Society
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    • v.17 no.6
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    • pp.85-98
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    • 2001
  • Cone penetration was analyzed by arbitrary Lagangian-Eulerian(ALE) method. In order to simulate full penetration, steady state analyses were performed using ABAQUS/Explicit, which models upward flow of soil layers. In the analysis of homogeneous layer it was found that the paths and the strain of soil particles were consistent with the result of the strain path method and that the ultimate resistance were reasonably evaluated. The cone penetration through different soil layers was also analyzed and that showed the transfer of cone resistance. The steady state ALE analysis could perform full penetration through the layered soils.

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최적관리제어

  • 이문상;조광현;임종태
    • ICROS
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    • v.6 no.4
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    • pp.38-48
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    • 2000
  • Abstract :본 논문에서는 관리제어시스템의 동적특성을 허용언어(admissible language) 범위 이내에서 최적화시키는 최적 관리제어기법들을 소개한다. 본 논문에서 주로 다루고자 하는 최적 관리제어기법은 Kumar와 Garg에 의해 제안된 기법과 Cho와 Lim에 의해 제안된 계층적 최적 관리제어기법, 그리고, Sengupta와 Lafortune이 제안한 최적 관리제어기법 등이다. 첫 번째 기법에서는 우선 시스템의 최적화를 위해 고려되고 있는 비용함수(cost function)를 소개한 후, 최대흐름 최소분할생성 정리(max-flow min-cut theorem)를 이용한 최적 관리제어기 설계기법을 제시하고, 이를 부분관측 하에서도 최적 관리제어기를 설계할 수 있도록 확장한다. 그런 후 제시된 설계기법에 의해 설계된 관리제어시스템에서 발생 할 수 있는 문제점들을 지적하고, Cho와 Lim에 의해 제안된 완전 최소분할생성(complete min-cut)이라는 개념을 도입하여 지적된 문제점들을 해결할 수 있는 방법을 제시한다. 또한 시스템의 고장을 고려한 계층적 최적 관리 제어(layered optimal supervisory control)기 법을 소개한다 그리 고 마지막으로 Sengupta와 Lafortune이 제안한 최적 관리제어기법에 대해서 살펴본다.

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Modeling saturated-unsaturated moisture flow in soils (포화층및 불포화층에 대한 토양수분흐름의 모델링)

  • 정상옥
    • Proceedings of the Korea Water Resources Association Conference
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    • 1988.07a
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    • pp.85-92
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    • 1988
  • A model for the transient one-dimensional moisture movement in the saturated-unsaturated zone using a finite difference method is developed. Hysteresis in the soil water retention is incorporated. The model considers layered geologic formations. Monte Carlo simulation, together with the nearest neighbor model is used. Outputs of the model include pressure head, water content, and the water table elevation. Two Monte Carlo simulations of 100 realizations each are made for a 12-day simulation period with different input values. The simulation results show that the S.D. of the outputs increases with an increase in the input, the S.D. of the log K$$. The model is applied to predict a long term water table fluctuation, and the predicted water table agress well with the observed one.

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Cross-Layer and End-to-End Optimization for the Integrated Wireless and Wireline Network

  • Gong, Seong-Lyong;Roh, Hee-Tae;Lee, Jang-Won
    • Journal of Communications and Networks
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    • v.14 no.5
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    • pp.554-565
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    • 2012
  • In this paper, we study a cross-layer and end-to-end optimization problem for the integrated wireless and wireline network that consists of one wireline core network and multiple wireless access networks. We consider joint end-to-end flow control/distribution at the transport and network layers and opportunistic scheduling at the data link and physical layers. We formulate a single stochastic optimization problem and solve it by using a dual approach and a stochastic sub-gradient algorithm. The developed algorithm can be implemented in a distributed way, vertically among communication layers and horizontally among all entities in the network, clearly showing what should be done at each layer and each entity and what parameters should be exchanged between layers and between entities. Numerical results show that our cross-layer and end-to-end optimization approach provides more efficient resource allocation than the conventional layered and separated optimization approach.

PREVENTION OF MURAL THROMBUS IN POROUS INNER TUBE OF DOUBLE-LAYERED TUBE BY SALINE PERFUSION (생리식염수의 재료표면에의 분출에 의한 이중튜브의 응혈 방지)

  • Kim, Sung-S.;Park, Joon-B.
    • Proceedings of the KOSOMBE Conference
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    • v.1993 no.11
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    • pp.110-113
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    • 1993
  • An in vitro experiment under laminar non-pulsatile blood flow and an acute canine ex vivo femoral A-V series shunt experiment were undertaken to investigate the effectiveness of saline perfusion through pores of porous tubes to prevent formation of mural thrombus. PS/SBR porous tubes were used for the in vitro experiment. Commercially obtained ePTFE porous tubes were etched by sodium naphthalenide, and the etched tubes were used for the ex vivo experiment. According to the results of the in vitro experiment, mural thrombus on the surface of the porous tribe could be prevented by the saline perfusion. Adhered blood cells decreased semi-logarithmically with increased perfusion rate (up to $0.022\;ml/min-cm^2$) of isotonic saline solution. According to results of the ex vivo experiment, mural thrombus decreased with increased perfusion rate (upto $0.060\;ml/min-cm^2$).

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Convergence Network Architecture for Global Manufacturing Execution System (글로벌 제조실행시스템을 위한 융합네트워크 구조)

  • Lee, Tae-Gyu;Shin, Seong-Yoon;Lee, Hyun-Chang
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.211-214
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    • 2014
  • Nowadays, manufacturing field are facing new challenges, through digital information and global integration, toward sophisticated production. This paper presents the system configuration and issues of current manufacturing execution system(MES), and describes major issues and solving elements to establish a MES system for cloud services. Also, it proposes business intelligence(BI) systems for building a manufacturing information system to have the optimized production flow and to respond appropriately to consumer market.

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