• 대한기계학회논문집B
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• 제27권8호
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• pp.1105-1113
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• 2003

In the gas wiping process of continuous hot-dip galvanizing, edge overcoating develops near the edge of the steel strip. The overcoating is supposed to occur due to the reduced impact pressure of wiping gas on the strip surface. The purpose of this study is to investigate the effect of edge vortex on the reduced impact pressure. Three-dimensional unsteady flows are simulated using a commercial code, STAR-CD. Standard k-$\varepsilon$ model is used as a turbulence model. It is found that an alternating vortex structure in the vicinity of strip edge is developed by buckling of opposed jet streams and that the reduced amount of impact pressure at strip edge becomes smaller as the air knife gets closer to the strip. The effect of edge baffle on the reduced impact pressure is also investigated.

• 대한기계학회논문집A
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• 제22권4호
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• pp.723-730
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• 1998

With the introduction of edge drop control system in Tandem Cold Rolling Mill, it is necessary to develop te numerical expression for the set-up and edge drop automatic control of cold rolled sheet. As a first step we developed a simulation program which predicts profile and the amounts of edge drop at the delivery side of each stand by using roll deformation anlysis with the slit roll model. And by using the program the effect of various rolling conditions on edge drop was investigated. As a result the relations were obtained between the amounts of edge drop and rolling conditions. Based on above relations, the numerical expression was developed for the set-up and automatic control of edge drop by multi-regression of simulation results for the variation of edge drop amount with each rolling condition.

• 한국멀티미디어학회논문지
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• 제19권6호
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• pp.990-1002
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• 2016

In this paper, we propose a new compression method for the edge image by analyzing the characteristics and the distribution of pixel values of the edge image. The pixel values of the edge image have the Gaussian distribution around '0', and most of the pixel values are `0`. By these analyses we suggest the Zero-Based codec that expresses all values in a CU by a single bit flag. Also, in order to reduce the computational complexity of the proposed codec, the block partition and the intra-prediction techniques are proposed by using edge information like the number of each edge direction, the distribution and the amplitude of a major edge direction in the CU. Experimental results show that the proposed codec leads to a slighter distortion in Y domain than that of HEVC, but has far faster processing speed up to 53 times while it maintains the similar image quality compared to HEVC.

• 반도체디스플레이기술학회지
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• 제22권4호
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• pp.7-12
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• 2023

The edge ring placed on the outside of the electrostatic chuck (ESC) is a key component for protecting the ESC and controlling the etching uniformity of the edge of the wafer. Therefore, it is very important to understand the etching phenomenon of edge rings for edge ring management and equipment homeostasis. In this study, a specimen with SiO₂ hard mask and underlying Si mold was installed on the edge ring surface and the etching results were measured by varying the edge ring 2MHz RF power. By developing PI-VM model with high prediction accuracy and analyzing the roles of key parameters in the model, we were able to evaluate the effect of plasma and sheath characteristics around the edge ring on edge ring erosion. This analysis method provided information necessary for edge ring maintenance and operation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.329-332
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• 1988

In this paper, A analysis method about air gap field of L.I.M. considering Transverse Edge Effect is suggested. Especially, the case of displacement of primary and secondary it can be analysed and criteria for design of L. I. M. is proposed by proving the influance of ratio of width for primary and secondary to the characteristic

• 한국해양공학회지
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• 제18권5호
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• pp.15-21
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• 2004

An edge tone is the discrete tone or narrow-band sound produced by an oscillating free shear layer, impinging on a rigid surface. In this paper, we present a 2-D edge tone to predict the frequency characteristics of the discrete oscillations of a jet-edge feedback cycle, using the finite difference lattice Boltzmann method (FDLBM). We use a modified version of the lattice BGK compressible fluid model, adding an additional term and allowing for longer time increments, compared to a conventional FDLBM, and also use a boundary fitted coordinates system. The jet is chosen long enough in order to guarantee the parabolic velocity profile of the jet at the outlet, and the edge consists of a wedge with an angle of ${\alpha}$ = 23. At a stand-off distance, the edge is inserted along the centerline of the jet, and a sinuous instability wave, with real frequency, is assumed to be created in the vicinity of the nozzle and propagates towards the downstream. We have succeeded in capturing very small pressure fluctuations, resulting from periodical oscillations of a jet around the edge. The pressure fluctuations propagate with the speed of sound. Its interaction with the wedge produces an non-rotational feedback field, which, near the nozzle exit, is a periodic transverse flow, producing the singularities at the nozzle lips.

• 대한기계학회논문집B
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• 제28권7호
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• pp.763-770
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• 2004

The problem of edge overcoating developed near the edge of the steel strip is studied quantitatively in the gas wiping process of continuous hot-dip galvanizing. It has been assumed that the edge overcoating occurs due to the reduced impact pressure of wiping gas on the strip edge and it is one of detrimental problems to the quality of coating products. In order to analyse the edge overcoating problem numerically, three-dimensional unsteady flows due to the gas wiping are calculated by using a commercial code, STAR-CD. Standard $\kappa$-$\varepsilon$ model is used as a turbulence model. The 1D code for calculation of coating thickness is constructed by using continuity and Navier-Stokes equations. The calculation results have shown good agreement with measurements of edge overcoating thickness, taken from galvanizing line trials. Therefore it is conformed that the major cause of edge overcoating is the reduced impact pressure of wiping gas on the strip surface.

• 한국컴퓨터정보학회논문지
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• 제10권6호
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• pp.17-26
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• 2005

본 논문에서는 통계학의 선형순위통계량(linear rank statistics)에 기초한 3가지 비모수 검정법 즉. Wilcoxon 검정법, Median 검정법 그리고 Van der Waerden 검정법을 이용하여 에지를 검출하고자 한다. 5$\times$5 윈도우상에서 중심픽셀의 에지여부는 에지-높이 모수(edge-height parameter)를 사용한 모형 하에서 두 영역간의 유의한 차이가 있는지를 검정함으로서 결정한다. 영상실험에서 통계적 방법들 간의 에지검출 성능은 에지맵(edge map)을 통한 정성적인 비교와 객관적인 척도 하에서 정량적인 비교를 통하여 분석하였다.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2018년도 제57차 동계학술대회논문집 26권1호
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• pp.5-6
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• 2018

Edge Computing의 성능 분석을 위해 SDN 테스트 베드를 구축하는 방안을 제안한다. Edge Computing 환경에서 연구한 알고리즘들을 실증적 성능 테스트하기 위해 테스트베드를 구축하였다. Raspberry-Pi를 이용해 SDN Switch를 구현하였고, Edge단의 노드는 테스트를 위해 노트북을 연결해 인터넷이 되는지 확인하였다. Edge Computing 환경은 수 많은 노드를 연결해 테스트해야 하며 따라서 SDN 환경이 적절하다. 본 논문에서는 SDN에 대해서 알아보고 Raspberry-Pi를 이용한 테스트 베드 구축 방안에 대해 소개하고자 한다.

• Steel and Composite Structures
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• 제29권5호
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• pp.681-688
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• 2018

In this paper, buckling load of edge stiffened composite plates is assessed. The effect of stiffener edge size, circular hole, and the fiber orientation angle on buckling behavior of composite plates under uni-axial compressive load is investigated. This paper includes two parts as experimental and numerical studies. L-shape composite plates are manufactured in three different layups. Then the buckling loads are experimentally determined. Subsequently, by using the numerical simulation, the size variation effects of stiffener edge and circular cutout on the plate buckling loads are analyzed in five different layups. The results show that cutout size, stiffener edge height and fiber orientation angle have important effects on buckling load. In addition, there is an optimum height for stiffener edge during different conditions.