• 제목/요약/키워드: Flow-through Model

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원격 PBL 수업에서 성취목표지향성, 학습동기, 몰입의 관계 탐색 : 흥미 수준의 매개효과를 중심으로 (Exploring the Relationship between Achievement Goal Orientation, Learning Motivation, and Flow in Distant PBL Classes: Focusing on the Mediating Effect of the Level of Interest)

  • 이은철
    • 한국콘텐츠학회논문지
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    • 제21권2호
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    • pp.395-405
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    • 2021
  • 본 연구는 원격 PBL 수업에서 몰입수준에 대한 성취목표지향성과 학습동기의 관계에서 흥미 수준의 매개 효과를 탐색하기 위해서 수행되었다. 선행연구 분석을 통해 몰입과 관련된 학습 요인들을 분석하여 이론적으로 구조모형을 구성하였다. 이론적으로 구성된 구조모형 검증을 위해 교직과목을 수강하는 사범학부 59명의 학생을 대상으로 하였다. 자료수집은 원격으로 PBL 수업을 수행한 이후 몰입, 성취목표지향성, 학습동기, 흥미수준을 설문을 통해 수집하였고, 수집된 자료는 구조방정식 모형 분석 방법을 사용하여 몰입에 대한 성취목표지향성과 학습동기, 흥미수준의 영향의 구조적 관계에 대해 분석하였다. 그 결과 본 연구에서 제안한 구조적 모형이 타당한 것으로 검증되었다. 이에 성취목표지향성과 학습동기의 영향을 흥미수준이 매개하여 몰입에 영향을 주는 것으로 검증되었으며, 성취목표지향성의 영향을 흥미수준이 매개하는 경로가 가장 큰 영향력을 가지고 있는 것으로 검증되었다. 이에 원격 PBL수업을 운영할 때, 학습자들의 성취목표 지향성을 고려하여 흥미수준을 조절한다면 몰입수준을 조절할 수 있다는 시사점을 제시할 수 있다.

Physical Model and Numerical Simulation Approach of Steam Flow and Heat Transfer of Pannier-arrangement Condensers

  • Hou, Pingli;Yu, Maozheng
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2004년도 제29회 KOSCI SYMPOSIUM 논문집
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    • pp.109-116
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    • 2004
  • Through analysing the influence of steam flow direction on the liquid formation and motion behavior in the condenser shell side, the physical model for existing numerical simulation program of condenser is improved by introducing the correlations for flow resistance and condensation heat exchange coefficient in which the influences of steam flow direction are considered according to the available experimental data. Thus a more suitable and general condenser simulation approach is presented and a new condenser calculation program is developed. With the experimental data of a pannier- arrangement experimental condenser, the adaptability of the new condenser simulation approach is verified. General characteristics of this type of condenser are also revealed.

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수중펌프의 Leakage-free 자동탈착장치 개발 (Development of Leakage-free Automatic Discharge Connect in a Submersible Pump.)

  • 최영석;이경용;이창한;이종훈
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2002년도 유체기계 연구개발 발표회 논문집
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    • pp.63-68
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    • 2002
  • ADC(Automatic Discharge Connector) is commonly used for the easy maintenance of the submersible pumps. However, the small gap between the flange of the base plate and that of the pipe due to the head rise, the flow momentum change and the mis-installation makes leakage flow that may be a great loss to the pumping system. In this study, the performance degradation was predicted with the simple leakage flow model through the gap. The newly developed ADC was tested and the leakage performance was compared with the old one and also no-leakage piping system. The newly developed ADC reduced the leakage flow in a satisfactory way in comparison with the old model.

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축소 유로내의 두 평행 유동에 대한 해석 (Analysis on Two Parallel Flows in Convergent Channel)

  • 권진경;김태욱;김진현;김재열
    • 한국추진공학회지
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    • 제10권4호
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    • pp.11-18
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    • 2006
  • 축소 유로에서의 두 평행 유동의 합류에 의한 복합유동과 그 초킹 현상이 일차원 등엔트로피 모델과 완전혼합 모델에 의해 계산되었다. 아음속-아음속의 복합유동에 대해 압력측정과 광학 측정이 실시되었으며 그 결과를 일차원 계산의 결과와 비교하였다. 결과적으로 복합유동의 한쪽 유동의 입구조건은 다른 유동의 거동과 초킹 조건에 영향을 미침을 알 수 있었으며 본 실험의 결과는 일차원 계산 결과와 비교적 잘 일치함을 알았다.

유동제어구조물에 의한 내만의 해수순환 모델링 (Hydraulic and Numerical Modeling of Seawater Circulation of Semi-enclosed Bay with the Flow-control Structures)

  • 김종규;강태순;김헌태
    • 한국해양공학회지
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    • 제14권3호
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    • pp.20-28
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    • 2000
  • Using the hydraulic and numerical model of semi-enclosed bay (Chinhae Bay), the efficiencies of flow-control structures on the seawater-circulation in the inner bay were investigated. Expecially, this study was confirmed the effectiveness of the flow-control structures at the mouth and narrow channel of Chinhae Bay through the experiments. The system of flow-control structures could enhance the water exchange improvement appropriately. The results of this study can be used as the long-term and integrated environmental impact assessment model in the inner bay.

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수중펌프의 Leakage-free 자동탈착장치 개발 (Development of Leakage-free Automatic Discharge Connector in a Submersible Pump.)

  • 최영석;이경용;이창한;이종훈
    • 한국유체기계학회 논문집
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    • 제6권2호
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    • pp.23-28
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    • 2003
  • ADC (Automatic Discharge Connector) is commonly used for the easy maintenance of the submersible pumps. However, the small gap between the flange of the base plate and that of the pipe due to the head rise, the flow momentum change and the mis-installation make a leakage flow that may be a great loss to the pumping system. In this study, the performance degradation was predicted with the simple leakage flow model through the gap. The newly developed ADC was tested, and the leakage performance was compared with the old one and also no-leakage piping system. The newly developed ADC reduced the leakage flow in a satisfactory way in comparison with the old model.

왕복동형 압축기의 경사진 원판형 밸브리드에 대한 압력분포 측정 및 유동해석 (Flow Analysis and Measurement of Pressure Distribution along Inclined Circular Valve Reeds of Reciprocating Compressor)

  • 윤정;박종호;김태민;김경천
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1942-1947
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    • 2003
  • The valve is the key part which governs the efficiency, noise and reliability of the compressor, so the development of analytical model about valve performance is necessary. As the valve leed is opened and closed by pressure pulsation, the flow characteristic of the refrigerant passing the valve is very important. In the present study, a circular disk with inclination is assumed to be the valve reed of a reciprocating compressor and numerical analysis of three dimensional velocity fields are perfomed for the radial flow through the valve model. The effective flow and force area which are required to predict the efficiency of the valve are measured and compared with the numerical analysis in this research.

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The Effect of the Intake Port Configuration on the Flow and Combustion in a 4-Valve Pentroof Gasoline Engine

  • Kim, Hongsuk;Lee, Jeongmin;Nakwon Sung
    • Journal of Mechanical Science and Technology
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    • 제15권2호
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    • pp.259-267
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    • 2001
  • The flow field in a cylinder of a 4-valve pentroof engine is studied using the KIVA-3V code. Turbulence is generated from the jet flow through valves and broken down to the small scale eddies in the compression process. It is known that the tumble effectively keeps turbulence during the compression process. In the combustion process, turbulence is known to enhance flame speed by increasing mass, momentum and heat transfer rates. The effects of the intake port angles on the flow and combustion characteristics are studied in this study. To study the effect of turbulence on the combustion process, Cantore combustion model is applied in this study.

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리니어 압축기 토출밸브계의 유효 유동면적 및 힘면적에 관한 실험적 연구 (Experimental Study for Effective Flow and Force Area of Discharge Valve System in a Linear Compressor)

  • 이병찬;이혁;안태길
    • 한국정밀공학회지
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    • 제23권7호
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    • pp.122-129
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    • 2006
  • The linear compressor has lately attracted considerable attention because of its low power consumption and excellent efficiency. For an efficient design, it is necessary to develop an analytical model of the linear compressor. The effective flow and force areas are important parameters to describe the behavior of the linear compressor, which are used to determine the mass flow rates through the valving systems and the forces on the valves, respectively. It is not easy to estimate these parameters because shapes of the valve systems of the linear compressor are so different from those of tile conventional valve systems. In this paper, we suggest method to measure experimentally the effective discharge flow and force areas of the linear compressor and analyze valve characteristic to apply the experimental results to their theoretical model.

원자로 부수로내 혼합날개를 지나는 삼차원 열유동 해석 (Numerical Analyses of Three-Dimensinal Thermo-Fluid Flow through Mixing Vane in A Subchannel of Nuclear Reactor)

  • 최상철;김광용
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2002년도 춘계 학술대회논문집
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    • pp.79-87
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    • 2002
  • The present work analyzed the effect of mixing vane shape on the flow structure and heat transfer downstream of mixing vane in a subchannel of fuel assembly, by obtaining velocity and pressure fields, turbulent intensity, flow-mixing factors, heat transfer coefficient and friction factor using three-dimensional RANS analysis. NJl5, NJ25, NJ35, NJ45, which were designed by the authors, were tested to evaluate the performances in enhancing the heat transfer. Standard $\kappa-\epsilon$ model is used as a turbulence closure model, and, periodic and symmetry conditions are set as boundary conditions. The flow blockage ratio is kept constant, but the twist angle of mixing vane is changed. The results with three turbulence models( $\kappa-\epsilon$, $\kappa-\omega$, RSM) were compared with experimental data.

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