• 항공우주시스템공학회지
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• 제10권3호
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• pp.39-43
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• 2016

In this paper, a wind-tunnel test is accomplished to investigate the roll characteristics of a variable-span wing flying inside a channel. The factors that affect the roll characteristics of the wing were identified by analyzing the measured data; accordingly, when the wing is flying without both the ground and sidewall effects, the asymmetric wing extension causes the roll moment. Both the ground and the sidewall can increase the roll moment, but when the wing is affected by both the ground and the sidewall, the roll moment does not increase as much as the case where the wing is only affected by the ground. Also, the aerodynamic characteristics of the flying wing inside a channel are the nonlinear function of the wing height and the gap between the wingtip and the sidewall, both of which should be considered in a study of the stability and the flight control of the wing-in-ground effect of the vehicle flying inside a channel.

• 대한기계학회논문집A
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• 제27권10호
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• pp.1667-1675
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• 2003

This paper has considered the calculation of lateral stiffness of radial tire's sidewall, which consists of cord stiffness and rubber sheet stiffness, by using the material constants of rubber compounds of tire. We have suggested and illustrated how to calculate the rubber sheet lateral stiffness by considering the following aspects. First, the rubber sheet consists of various kinds of rubber compounds with different thickness along the sidewall in the radial direction. Secondly, equivalent Young's modulus of the rubber sheet can be calculated by using available experimental data of rubber compounds. The present method enables us to divide the calculation domain as many as we want, which can reduce numerical error in the calculation of geometrical and mechanical properties. We have illustrated the calculation by using the data of the radial tire for passenger car of P205/60R15.

• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.1131-1137
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• 2015

Gallium nitride (GaN) is a promising material for next-generation high-power applications due to its wide bandgap, high breakdown field, high electron mobility, and good thermal conductivity. From a structure point of view, the vertical device is more suitable to high-power applications than planar devices because of its area effectiveness. However, it is challenging to obtain a completely upright vertical structure due to inevitable sidewall slope in anisotropic etching of GaN. In this letter, we design and analyze the enhancement-mode n-channel vertical GaN MOSFET with variation of sidewall gate angle by two-dimensional (2D) technology computer-aided design (TCAD) simulations. As the sidewall slope gets closer to right angle, the device performances are improved since a gradual slope provides a leakage current path through the bulk region.

• Applied Microscopy
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• 제52권
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• pp.1.1-1.8
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• 2022

As semiconductor device architecture develops, from planar field-effect transistors (FET) to FinFET and gate-all-around (GAA), there is an increased need to measure 3D structure sidewalls precisely. Here, we present a 3-Dimensional Atomic Force Microscope (3D-AFM), a powerful 3D metrology tool to measure the sidewall roughness (SWR) of vertical and undercut structures. First, we measured three different dies repeatedly to calculate reproducibility in die level. Reproducible results were derived with a relative standard deviation under 2%. Second, we measured 13 different dies, including the center and edge of the wafer, to analyze SWR distribution in wafer level and reliable results were measured. All analysis was performed using a novel algorithm, including auto fattening, sidewall detection, and SWR calculation. In addition, SWR automatic analysis software was implemented to reduce analysis time and to provide standard analysis. The results suggest that our 3D-AFM, based on the tilted Z scanner, will enable an advanced methodology for automated 3D measurement and analysis.

• 한국전산유체공학회지
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• 제18권4호
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• pp.74-81
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• 2013

A numerical design analysis is conducted to search for an optimal shape of outlet in a rotating-disk CVD reactor. The goal is to suppress flow recirculation that has been found in a reactor having a sudden expansion of flow passage outside of the rotating disk. In order to streamline gas flow, the sidewall at which the flow in the Ekman layer is impinged, is tilted. The axisymmetric laminar flow and heat transfer in the reactor are simulated using the incompressible ideal gas model. For the conventional vertical sidewall, the flow recirculation forming in the corner region could be expanded into the interior to distort the upstream flow. The numerical results show that this unfavorable phenomenon inducing back flow could be dramatically suppressed by tilting the sidewall at a certain range of angle. The assessment of deviation in deposition rate based on the characteristic isotherm illustrates that the sidewall tilting may expand the domain of stable plug-like flow regime toward higher pressure. A physical interpretation is attempted to explain the mechanism to suppress flow recirculation.

• 대한토목학회논문집
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• 제26권2B호
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• pp.139-144
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• 2006

측벽이 존재하는 개수로 난류흐름에 대한 DNS 자료를 사용하여 레이놀즈 전단응력 및 이차흐름의 생성메커니즘을 규명하였다. 측벽 부근에서 이차흐름의 양상을 보면, 상부 및 하부 모서리 부근에서는 측벽을 향해 침투되는 이차흐름이 형성된 반면, 그 외의 영역에서는 수로 중앙을 향해 분출하는 이차흐름이 형성된 것으로 나타났다. 측벽 부근에서 레이놀즈 전단응력의 분포를 산정하였으며, 고유구조와 연계하여 분석하였다. 사분면 해석에서 측벽을 향해 침투되는 이차흐름이 생성된 영역에서는 쓸기현상이 지배적인 반면, 측벽으로부터 분출되는 이차흐름이 형성된 영역에서는 분출현상이 지배적인 것으로 나타났다. 또한 조건부 사분면 해석을 통해 레이놀즈 전단응력의 생성 및 이차흐름의 양상이 지배적인 고유구조의 방향성에 의해 결정된다는 것을 확인하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2013년도 추계학술대회
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• pp.56-57
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• 2013

This paper is mainly concerned with the interaction effects between two vessels and sidewall with a mound. Experimental study on hydrodynamic forces between ship and sidewall with a mound was already shown in the previous paper, measured by varying the distances between ship and sidewall. The ship maneuvering simulation was conducted to find out the minimum safe distance between vessels, which is needed to avoid sea accident in confined waters.

• 한국전기전자재료학회논문지
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• 제17권10호
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• pp.1029-1033
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• 2004

In this paper, we propose a new Suppressed Sidewall Injection Magnetotransistor(SSIMT) architecture, which allows to overcome the restriction of the standard CMOS technology and achieve high linearity. The proposed SSIMT is designed based on the Hynix 0.6 um standard CMOS technology. The fabricated SSIMT has been experimentally verified. The SSIMT shows that the change of collector current is extremely linear as a function of the magnetic induction at $I_{B}$ =500$\mu$A, $V_{CE}$ =2V and VSE =5 V. The relative sensitivity is up to 120 %/T. The magnetic conversion offset is about 79 mT with 30.5 %/T relative sensitivity. The nonlinearity of the fabricated SSIMT is measured about 1.4 %.%.

• 전자공학회논문지A
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• 제33A권4호
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• pp.112-120
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• 1996

With the MOsES (mask oxide sidewall etch scheme)process which uses the conventional i-line stepper and isotropic wet etching, CMOSFET's with fine gate pattern of 0.1.mu.m CMOSFET device, the screening oxide is deposited before the low energy ion implantation for source/drain extensions and two step sidewall scheme is adopted. Through the characterization of 0.1.mu.m CMOSFET device, it is found that the screening oxide deposition sheme has larger capability of suppressing the short channel effects than two step sidewall schem. In cse of 200.angs.-thick screening oxide deposition, both NMOSFET and PMOSFET maintain good subthreshold characteristics down to 0.1.mu.m effective channel lengths, and show affordable drain saturation current reduction and low impact ionization rates.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.370-374
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• 2016

We investigated the three dimensional turbulent flow characteristic around a sidewall-mounted rectangular block using a laboratory flume experiment. The experiment was conducted in the flume which is 18m long and 0.9m wide, and a rectangular block that is 0.3m wide and a height of 0.4m and 0.004m thick is mounted on a sidewall of the flume. Velocity data were collected using Acoustic Doppler Velocimeter(ADV) for the flow rate conditions : $0.0528m^3/s$. The time-averaged velocity and water depth data were analyzed to examine the three-dimensional flow patterns downstream of the rectangular block.