• 제목/요약/키워드: Field Applicability

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Analysis of conventional drag and lift models for multiphase CFD modeling of blood flow

  • Yilmaz, Fuat;Gundogdu, Mehmet Yasar
    • Korea-Australia Rheology Journal
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    • 제21권3호
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    • pp.161-173
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    • 2009
  • This study analyzes especially drag and lift models recently developed for fluid-solid, fluid-fluid or liquid-liquid two-phase flows to understand their applicability on the computational fluid dynamics, CFD modeling of pulsatile blood flow. Virtual mass effect and the effect of red blood cells, RBCs aggregation on CFD modeling of blood flow are also shortly reviewed to recognize future tendencies in this field. Recent studies on two-phase flows are found as very useful to develop more powerful drag-lift models that reflect the effects of blood cell's shape, deformation, concentration, and aggregation.

트랙터 부착용(附着用) 토양심하(土壤沈下) 및 전단(剪斷) 시험기(試驗器)의 설계(設計) (Design of a Tractor mountable Bevameter)

  • 류관희;김경욱;손상순
    • Journal of Biosystems Engineering
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    • 제12권4호
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    • pp.1-8
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    • 1987
  • New design of a bevameter was attempted to that it can be not only attached to and powered by the tractor hydraulic control system, but is equipped with a data acquisition system using a microcomputer. Results of field tests of the new design showed that it has a good performance and practical applicability to the measurements of pressure-sinkage and shear stress-displacement relations from which toil parameters of the Bekker theory can be evaluated.

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Optimal Design of Superframe Pattern for DVB-RCS Return Link

  • Lee, Ki-Dong;Cho, Yong-Hoon;Lee, Seung-Joon;Lee, Ho-Jin
    • ETRI Journal
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    • 제24권3호
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    • pp.251-254
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    • 2002
  • We developed a method for optimal superframe design in the multi-frequency time division multiple access (MF-TDMA) return-link of a satellite multimedia interactive network called a digital video broadcasting return channel over satellite (DVB-RCS) sub-network. To find the optimal superframe pattern with the maximum data throughput, we formulated the design problem as a non-linear combinatorial optimization problem. We also devised the proposed simple method so that it would have field applicability for improving radio resource utilization in the MF-TDMA return link.

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상대변위를 이용한 지반정수 인식 (Identification of Geotechnical Paramters Using Relative Convergence Measurements)

  • 최상현;조국환
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2005년도 추계학술대회 논문집
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    • pp.418-423
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    • 2005
  • In designing underground structure such as tunnels, estimating geotechnical characteristics of the ground is one of the most important and difficult tasks. In this paper, a methodology that can identify geotechnical parameters using only field-measured relative convergence displacements is presented. By using only relative convergence measurement data, inevitable errors in absolute convergence estimation can be avoided and in turn the parameter estimation process can be simplified. The methodology utilizes sensitivity relationship between static displacement measurements and geotechnical parameters. The feasibility and applicability of the proposed methodology is verified via a 3-d numerical example of a tunnel structure.

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Structural Aspects in the Theory of Random Walk

  • Heyer, H.
    • Journal of the Korean Statistical Society
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    • 제11권2호
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    • pp.118-130
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    • 1982
  • Random walks as specia Markov stochastic processes have received particular attention in recent years. Not only the applicability of the theory already developed but also its extension within the frame work of probability measures on algebraic-topological structures such as semigroups, groups and linear spaces became a new challenge for research work in the field. At the same time new insights into classical problems were obtained which in various cases lead to a more efficient presentation of the subject. Consequently the teaching of random walks at all levels should profit from the recent development.

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JSA 위험성평가 기법의 현장 적용성 강화 방안 연구 (Study on Ways to Strengthen Field Applicability of JSA Risk Assessment Techniques)

  • 조보현
    • 한국재난정보학회:학술대회논문집
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    • 한국재난정보학회 2023년 정기학술대회 논문집
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    • pp.151-152
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    • 2023
  • 본 연구는 근로자의 행동을 현장 모니터링 즉 관찰을 통해 불안전한 행동 유발 요인들을 JSA 위험성평가를 실시하는 작업분석으로 올바른 안전작업절차서를 작성함으로써 이를 통한 불안전한 행동 요인을 제거하고 사고 및 재해를 예방할 수 있다.

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하수구조물용 항균콘크리트의 개발 및 현장적용 (Development of Antimicrobial Concrete for Sewage Structures and Application to Construction Field)

  • 김무한;김규용;이의배;이승훈;손유신
    • 한국건축시공학회지
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    • 제6권3호
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    • pp.91-97
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    • 2006
  • Sewage facilities are positively necessary for environment improvement such as rainwater removal, sewage disposal, preservation of the qualify of water and health of the citizens in present-day. Meanwhile, a deterioration of the concrete sewer pipe is increasing rapidly due to the chemical and physical attack and especially biochemical attack that is to say biodeterioration. In this study, researches for the development of antibiotics and antimicrobial concrete were conducted to reduce biochemical corrosion of sewage concrete. First of all, desired performance, such as watertightness, antibiosis, homogeneity, workability and harmlessness, was proposed and performance of antibiotics and antimicrobial concrete were evaluated by them. And developed antimicrobial concrete was applied to actual construction field. As results of this study, dispersibility and antibiosis of liquid antibiotics superior to powdery antibiotics. Antibiosis of antimicrobial concrete was verified, and amount of elution of harmful and effective ingredients was little. In workability, setting time of antimicrobial concrete was delayed. Compressive strength and resistance to carbonation of antimicrobial concrete were more increased than ordinary concrete. Finally, as there were no problems in quality and construction progress of antimicrobial concrete produced in plant, applicability of antimicrobial concrete to actual construction field was verified.

선체주위의 점성유동 계산을 위한 3차원 공간 격자계 생성방법 (Development of 3-D Field Grid Generating Method for Viscous Flow Calculation around a Practical Hull Form)

  • 김우전;김도현;반석호
    • 대한조선학회논문집
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    • 제36권1호
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    • pp.70-81
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    • 1999
  • 선체주위의 점성유동을 계산하기 위해서는 수치계산을 위한 3차원 공간 격자계가 필요하다. 본 논문에서는 타원형 미분 방정식인 Poisson 방정식의 해를 이용하여 3차원 공간 격자계를 구성하는 방법을 개발하였다. 2차원에서 사용되던 Sorenson방법을 3차원으로 확장하여 격자계의 분포 및 교차 각도를 지정하는 함수를 정의하게 하였다. 미분방정식의 해는 weighting function scheme과 modified strongly implicit procedure를 사용하여 구하였고, 3차원 내부 격자계와 경계면과의 매끄러운 연결을 위해 trans-finite interpolation을 이용하였다. 적용예로서 컨테이너 운반선과 대형 유조선 주위의 난류유동 계산을 위한 공간 격자계를 보였다.

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초고압 GCB 소호부내의 열가스 유동해석 (Analysis of the hot gas flow field in a interrupter of UHV GCB)

  • 송기동;박경엽;이병윤
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 A
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    • pp.372-375
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    • 1999
  • This paper presents an arc(hot-gas flow field) analysis method in GCB. This method includes the Lorentz's force due to magnetic field, turbulent viscous effect and radiation heat transfer which are indispensable to the analysis of hot-gas flow. To verify the applicability of the Proposed method, steady state hot-Eas flow analysis within a simplified interrupter has been carried out. Inlet boundary pressure values were assumed to be 9.0atm and 12.0atm. For each inlet boundary condition, three cases of hot-gas flow field analyses were performed according to the values of arc currents which were assumed to be D.C 0.6kA. 1.0kA and 2.0kA. The results revealed that the arc radius at nozzle throat has been concentrated by increasing the pressure of nozzle upstream and that the maximum temperature of arc core has been decreased along to nozzle exit and the high temperature lesion come to be wide in nozzle downstream. From these results, it is confirmed that the proposed method will be applicable to predict the large current interruption capability of GCB.

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