• 대한기계학회논문집
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• 제13권5호
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• pp.979-990
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• 1989

본 연구에서는 종횡비가 1보다 크고 내부 벽면에 일정한 열유속을 가지고 외부벽은 등온으로 유지되며 나머지 벽은 단열된 수직환형 원통형에 대한 연구를 바탕으로 같은 경계조건으로 종횡비를 1이하로 감소할 때에 Darcy의 법칙을 기초로 유한차분법을 사용, 수치적으로 해석하여 다세포 유동의 존재 여부와 온도 분포 및 열전달율을 계산하였다.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2010년도 하계학술대회
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• pp.353-355
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• 2010

Optical flow 는 컴퓨터 비전에서 기본적이고 중요한 연구 분야 중에 하나이며 지금까지 많은 알고리즘이 제안되었다. 그러나 여전히 Optical flow의 많은 기법들은 텍스처가 없는 영역들과 이미지의 경계부분에서 정확한 결과를 얻는 데 많은 어려움을 갖고 있으며 이러한 Optical flow 의 성능을 평가하기 위해서 지금까지는 Endpoint Error 와 Angular Error 등과 같은 방법을 사용하고 있다. 이 논문에서는 유명한 optical flow 기법들을 초기 모델부터 최근 기법까지 간략하게 설명함으로써 optical flow 기법들이 어떻게 진행되어 왔는지 살펴보고 특히 occlusion 영역과 경계부분에서의 성능을 평가하였다.

• KSBB Journal
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• 제10권5호
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• pp.482-490
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• 1995

The relationship between pressure drop and liquid flow rate, for an axial and a radial flow chromatographic column packed with compressible porous media was theoretically analyzed using modified Kozeny-Carman equation. The results were compared with experimental observations obtained using compressible DEAE-agarose as a model medium. At 2-9 psi range studied, the theoretical derivation accounting for 'gel compression' effect predicted simple Langmuirian type response of volumetric flow rate to changes in pressure drop. On the other hand, the experimental response was more or less sigmoidal. At the same pressure drop, radial column showed 2-3 times higher flow rates than those of axial column both theoretically and experimentally. Using r-HBsAg crude extract, protein resolution effects between the two types of columns at different flow rates were compared side-by-side. It turned out that, though general chromatographic behavior was very similar, axial column was somewhat superior in terms of r-HBsAg recovery yield and specificity. However, the number of theoretical plates analysis indicated the protein resolution effects were comparable.

• 한국물환경학회지
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• 제21권4호
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• pp.327-331
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• 2005

The study was conducted with two laboratory biological aerated filter (BAF) reactors: denitrification filter (DF) and nitrification BAF. The influent flow (Q) was fixed to 48 L/d and total empty bed contact time (EBCT) was 1 hr. The flow direction was upflow with NRCY of 1 to 2Q. The secondary effluent was fed to the reactors and the influent concentrations were adjusted with some stock solutions to simulate by-pass concentration during rainfall. The study results indicate that COD and SS removal efficiencies were excellent and not influenced by temperature. Nitrification efficiency was over 90% at the influent loading less than $1.12kg/media\;m^3/d$, but the efficiencies were decreased in low temperature. TN removal efficiencies were 10% to 60%.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.168-174
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• 2000

This paper illustrates the validity of reciprocating type superadiabatic combustor as a industrial applicable dryer. After the investigations of inner and surface temperature distributions of combustor various with air-fuel(methane) ratio, mixture flow rate and reciprocating time, this combustor can be applied in industrial dryer at certain operating conditions. The results are as follows. 1) Higher equilivalence ratio emits more radiation heat flux at the censer chamber 2) Higher mixture flow rate makes more uniform temperature distribution. however, due to the heat transfer from censer chamber to porous media, the radiation beat flux is worse. 3) Longer reciprocating time emit more radiation heat flux. however, this case also makes temperature distribution wide

• Computers and Concrete
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• 제30권1호
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• pp.1-8
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• 2022

The basic purpose of the current study is to compute the numerical analysis of heat source/sink for Darcy-Forchheimer three dimensional nanofluid flow with gyrotactic microorganism by rotatable disk via porous media under the slip conditions. Due to nanoparticles, random and thermophoretic motion phenomenon occurs. The governing mathematical model is handled numerically by shooting method. Additionally, the characteristics of velocities, mass, heat, motile microorganisms and associated parameters are thoroughly analyzed via plots and tables. Different physical parameters like Forchheimer number, slip parameters like velocity, porosity parameter, Prandtl number, Brownian number, thermophoresis parameter, heat sink/source parameter, bioconvected Rayleigh number, buoyancy parameteron dimensionless velocities, temperature. Approximate values of Sherwood microorganism are analyzed.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.249-251
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• 2014

Synthesis gas such as hydrogen and carbon monoxide was produced from $CH_4//oxygen$ mixture using two-section porous media combustor. Heat recirculation through the inner foam structure could extend the flow velocity of stable region over the laminar burning velocity. $H_2/CO$ ratio and module M from concentration of flue gas measured by Gas Chromatography was similar to those calculated by equilibrium. But it was made sure that the heat loss effect becomes more influential than heat recirculation effect as the mixture gets richer. To generate synthesis gas appropriate for methanol production, insulated pressurized porous media combustor will be designed and built in the future.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.132-135
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• 2001

To understand and compare tracer transport in fractured and porous media. multiple tracer tests were conducted in Wonju and Uiwang sites. The target media were fractured in Wonju site and porous in Uiwang site. It was known that groundwater flow for the two hydrogeologic systems could be represented using a EPM approach. However, the tracer transport in the two aquifer systems was greatly different. In this study, we analyzed the different tracer transport behavior in the two systems, from which our understanding of the tracer dispersion was greatly enhanced. we used bromide and chloride as tracers.

• 신재생에너지
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• 제10권4호
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• pp.29-35
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• 2014

Non-used waste heat has recently been paid special attention due to several global warming regulation and energy cost rising. In this study, therefore, thermal energy storage system which uses a solid type heat media has been investigated about the possibility of heat accumulation and heat release for thermal energy storage system. 35kWh of bench-scale thermal storage system was used to investigate the characteristics of the solid type heat media. From the result, it is shown that a solid type heat media should be divided to supply constant heat to the customers' side. It is also shown the flow direction should be considered to reduce temperature difference between top and bottom sides in the thermal storage system.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.193-198
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• 2009

Generally a TV broadcast video of ball sports is composed from those of multiple cameras strategically mounted around a stadium under the supervision of a master director. The director decides which camera the current view should be from and how the camera work should be. In this paper, such a decision rule is based on the 3D location of ball which is the result of multi-view tracking. While current TV sports broadcast are accompanied with professional cameramen and expensive equipments, our system requires few video cameras and no cameraman. The resulted videos were stable and informative enough to convey the flow of a match.