• 한국해양공학회지
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• 제19권4호
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• pp.9-14
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• 2005

In the present paper, the wave absorbing performance of the fully submerged horizontal porous plates has been investigated, numerically and experimentally. The submerged porous system is composed of multi-layered horizontal porous plates that are clamped at the vertical setwall, which are slightly inclined and placed vertically, in parallel, with spacing. The hydrodynamic interaction of incident waves with the rigid porous multi-layered plates was formulated within the context of linear wave-body interaction theory and Darcy's law. In order to validate the effectiveness of the present computing code, the numerical results were compared with the analytical and experimental results. It is found that triple horizontal porous plates with slight inclination, if properly tuned for wave energy dissipation against the standing waves in front of the vertical wall, can have high performances in reducing the reflected wave amplitudes against the incident waves over a wide range of wave frequency.

• 한국산업융합학회 논문집
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• 제8권2호
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• pp.105-112
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• 2005

The characteristics of natural convection heat transfer combined with radiation in a vertical parallel plates has been investigated experimentally. The vertical channel is consisted with a heated wall and three protruding heating sources attached on the opposite wall. The cooling of modules has been experimented with heating the wall as well as modules themselves at different aspects ratios and heating fluxes. As the location of module is higher, the temperature becomes higher, but the increasement is smaller. When the aspect ratio is lower than 26, its effect on the temperature is not significant rather than that of the radiation heat transfer. Furthermore, the correlation of Nusselt number with the Rayleigh number are attempted, but additional treatment is needed to accomodate the cases of heating module and/or opposite wall.

• Journal of Welding and Joining
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• 제21권4호
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• pp.31-38
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• 2003

Line heating is an effective and economical process for forming flat metal plates into three-dimensional shapes for plating of ships. Because the nature of the line heating process is a transient thermal process, followed by a thermo elastic plastic stress field, predicting deformed shapes of plate is very difficult and complex problem. In this paper, neural network model o3r solving the inverse problem of metal forming is proposed. The backpropagation neural network systems for determining line-heating positions from object shape of plate are reported in this paper. Two cases of the network are constructed-the first case has 18 lines which have different positions and directions and the second case has 10 parallel heating lines. The input data are vertical displacements of plate and the output data are selected heating lines. The train sets of neural network are obtained by using an analytical solution that predicts plate deformations in line heating process. This method shows the feasibility that the neural network can be used to determine the heating-line positions in line heating process.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.280-282
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• 2003

In this paper we tried to analyze through the water tank model to solve these kinds of problems about the square plate earth electrode using general facilities with being compared with the theory formula announced before. The square plate earth electrode that haven't investigated so far is analyzed by being based on laid rod electrode. And the each kind of calculation model was investigated with the experiment of water tank. An experiment of the vertical square Plate electrode about laying depth in the center of the surface of the water has already done with the practical models that have different forms of electrodes.

• 대한조선학회지
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• 제22권1호
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• pp.9-20
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• 1985

Generally the stiffened plate in the ship structure is subjected to not only axial load but shear load. With respect to those combined loads buckling analysis in necessary. In this paper, buckling strength is analyzed by using Finite Element Method when the stiffened plate with hole is under loading conditions mentioned above. To obtain the higher buckling strength, we need some reinforcement. The methods of reinforcement are attaching doubler around hole and stiffeners in the arbitrary directions For the sake of convenience those arbitrary directions were selected paralleled($0^{\circ}C$), vertical($90^{\circ}C$)and oblique($45^{\circ}C$) to the edge. Two kinds of method mentioned above are investigated, it is clarified that which of the two is more effective reinforcement. From the viewpoint of buckling strength, following conclusions were obtained. When external load direction is unknown, doubler reinforcement is more effective than those of parallel and vertical stiffener. And oblique stiffener reinforcement is more effective than that of doubler when external load direction is know.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.953-956
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• 2005

Low voltage actuation and high isolation characteristics are key features to be solved in electrostatic RF switch design. Since these parameters in the conventional parallel plate MEMS switch design are in trade-off relation, both requirements cannot be met simultaneously. In vertical comb design, however, the actuation voltage is independent to the vertical separation distance between the contact electrodes. Then, we can design the large separation distance between contact electrodes to get high isolation. We have designed an RF MEMS switch which has -40dB isolation at 5 GHz and 6 V operation voltages. The characteristics of the fabricated switch are being evaluate.

• 대한기계학회논문집
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• 제15권5호
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• pp.1774-1780
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• 1991

본 연구에서는 유한 길이를 갖는 수직 덕트내 공기 유동의 속도 분포를 LDV를 사용하여 측정하며 유동 특성에 미치는 가열정도, 덕트간격 및 입구소도등의 영향을 보고하고자 한다. 또한 속도분포, 온도분포 및 열전달에 미치는 부력의 영향을 수치 적으로 예측하여 그 타당성을 검증하고자 한다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제1권3호
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• pp.189-192
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• 2001

A simple metal-insulator-metal (MIM) capacitor in a standard $0.25{\;}\mu\textrm{m}$ digital CMOS process is described. Using all six interconnect layers, this capacitor exploits both the lateral and vertical electrical fields to increase the capacitance density (capacitance per unit area). Compared to a conventional parallel plate capacitor in the four upper metal layers, this capacitor achieves lower parasitic substrate capacitance, and improves the capacitance density by a factor of 4. Measurements and an extracted model for the capacitor are also presented. Calculations, model and measurements agree very well.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제24권1호
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• pp.103-119
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• 2020

In this work, the hydromagnetic and thermal characteristics of natural convection flow in a vertical parallel plate micro-porous-channel with suction/injection is analytically studied in the presence of Hall current by taking the temperature jump and the velocity slip at the wall into account. The governing equations, exhibiting the physics of the flow formation are displayed and the exact analytical solutions have been obtained for momentum and energy equations under relevant boundary conditions. The impact of distinct admissible parameters such as Hartmann number, Hall current parameter, permeability parameter, suction/injection parameter, fluid wall interaction parameter, Knudsen number and wall-ambient temperature ratio on the flow formation is discussed with the aid of line graphs. In particular, as rarefaction parameter on the micro-porous-channel surfaces increases, the fluid velocity increases and the volume flow rate decreases for injection/suction.

• 조명전기설비학회논문지
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• 제22권12호
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• pp.122-129
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• 2008

본 논문은 실내에 잔존하는 직경 1[${\mu}m$] 이하의 미세먼지들을 집진하기 위하여 전기집진기를 설계하였으며, 이때 집진 효율의 극대화를 위하여 전계와 동시에 자계를 수직 및 수평으로 배치함에 따른 실험실 공기중에 포함된 미세먼지의 집진특성에 대하여 논하였다. 전계에 수평으로 자계를 인가한 경우는 자계의 유무 및 자석의 수량에 관계없이 집진효율이 거의 일정하게 나타났으며, 자석을 수평으로 배치하여 전계에 수직으로 인가한 경우는 비자화 페라이트 막대를 부착한 경우보다 약 5[%] 이상 집진효율이 향상되었다. 또한, 자계를 전계에 수직으로 인가하는 방법에 있어서, 자석을 접지전극의 가운데 정렬한 경우는 인가전압 5[kV]에서의 집진효율이 $17{\sim}32[%]$로서 자석을 앞쪽에 설치한 경우와 유사하였으며, 지그재그 및 안쪽 끝에 정렬시킨 경우는 집진효율이 $17{\sim}38[%]$로서 향상되었으며, 특히 0.7 및 1[${\mu}m$]의 굵은 입자들에 대한 집진특성이 양호하였다. 따라서, 전기집진기의 집진특성을 향상시키기 위해서는 자계를 전계에 수직으로 접지전극의 중간 또는 지그재그 식으로 배치하는 것이 가장 적절한 것으로 판단된다.