• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 제35회 춘계학술대회
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• pp.272-278
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• 2002

Recently, STI(Shallow Trench Isolation) process has attracted attention for high density of semiconductor device as a essential isolation technology. In this paper, the effect of pattern density, trench width and selectivity of slurry on dishing in STI CMP process was investigated by using specially designed isolation pattern. As trench width increased, the dishing tends to increase. At $20{\mu}m$ pattern size, the dishing was decreased with increasing pattern density Low selectivity slurry shows less dishing at over $160{\mu}m$ trench width, whereas high selectivity slurry shows less dishing at below $160{\mu}m$ trench width.

• 한국연초학회지
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• 제9권2호
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• pp.37-47
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• 1987

This experiment was conducted to obtain basic information on breeding of flue-cured tabacco varieties . Nine cultivars and partial diallel set of 36 Fl hybrids were grown at Daegu Experiment Station, Korea Ginseng & Tobacco Research Institute in 1983. Partial dominance with high additive gene effect was observed for yield, leaves per plant , days to flower, leaf weight, nicotine and reducing sugar content. partial dominance with additive and dominant gene effect was observed for stalk height , leaf width midrib weight Overdominance with high dominant gene effect was observed for leaf length and midrib width. The directions of dominance were positive for yield, stalk height, leaf weight, leaf length, leaf width, midrib weight, midrib width and reducing sugar content, and the negative was days to flower. The estimates of effective genes were 1 for leaves per plant, 2 for stalk height, days to flower and leaf shape. 3 to 6 for leaf length, leaf width, leaf weight and midrib weight.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.227-232
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• 2002

This paper describes a calculation of an average crack spacing and the maximum crack width for the high-strength concrete tensile and flexural members. Based on the uniform bond stress distribution of the average steel and concrete strains over the transfer length, the crack spacing and the crack width are proposed to utilize influence of the concrete strength and the cover thickness. This analytical results presented in this paper indicate that the proposed equations can be more effectively estimated the maximum crack width and the average crack spacing of the reinforced concrete flexural and tensile members.

• 대한기계학회논문집
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• 제4권3호
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• pp.113-118
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• 1980

Stresses were calculated for finite-width orthotropic laminates with a circular hole and remote uniaxial loading using a two-dimensional finite-element analysis with both uniform stress and uniform displacement boundary conditions. Five different laminates were analyzed: quasi-isotropic [0.deg./.+-.45.deg./90.deg.].$\_$s/, 0.deg., 90.deg., [0.deg./90.deg.]$\_$s/, and [.+-.45.deg.]$\_$s/, Computed results are presented for selected combinations of hole diameter-sheet-width ratio d/w and length-to width ratio L/w. For small L/w values, the stress-concentration factors K$\_$tn/ were significantly different for the uniform stress and uniform displacement boundary conditions. Typically, for the uniform stress conditions, the K$\_$tn/ values were much larger than for the infinite-strip reference conditions; however, for the uniform displacement conditon, they were only slighty smaller than for this reference. The results for long strips are also presented as width-correction factor. For d/w.leg.33, these width-correction factors are nearly equal for all five laminates.

• Structural Engineering and Mechanics
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• 제62권6호
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• pp.719-724
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• 2017

We consider an elastic isotropic plate reinforced by stringers and weakened by a periodic system of rectilinear slots of variable width. The variable width of the slots is comparable with elastic deformations. We study the case when the slots faces get in contact at some area. Determination of parameters characterizing the partial closure of variable width slots is reduced to the solution of a singular integral equation. The action of the stringers is replaced with unknown equivalent concentrated forces at the points of their connection with the plate. The contact stresses and contact zone sizes are found from the solution of the singular integral equation.

• Structural Engineering and Mechanics
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• 제2권2호
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• pp.197-210
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• 1994

Presented in this paper is the rigorous analysis for the determination of effective flange width for composite beams. To make the solution suitable for routine design, formulas and tables for determining effective flange width for varying load types and geometric shapes are suggested. A variety of effective flange width problems for simple and continuous T- and I-beams can be solved by these tables and formulas. Although they are derived for T- and I-beams with symmetrical shapes, flanges and loads, they can be applied for non-symmetrical cases. Typical numerical examples are given to show how to use the formulas and tables; and their validity and accuracy are assessed by comparison with other known results that are based on the American Codes AISC, AASHTO and ACI.

• Journal of Communications and Networks
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• 제12권6호
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• pp.600-604
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• 2010

A method of width adaptation in the radial basis function network (RBFN) using stochastic gradient (SG) algorithm is introduced. Using Taylor's expansion of error signal and differentiating the error with respect to the step-size, the optimal time-varying step-size of the width in RBFN is derived. The proposed approach to adjusting widths in RBFN achieves superior learning speed and the steady-state mean square error (MSE) performance in nonlinear channel environment. The proposed method has shown enhanced steady-state MSE performance by more than 3 dB in both nonlinear channel environments. The results confirm that controlling over step-size of the width in RBFN by the proposed algorithm can be an effective approach to enhancement of convergence speed and the steady-state value of MSE.

• 한국디지털건축인테리어학회논문집
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• 제11권2호
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• pp.31-39
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• 2011

Concrete-filled steel tube(CFT) columns have become popular for building construction due to not only composite effect of steel tube and infilled concrete, but also more economical. The purpose of this paper is to propose the applicable boundary formula of width-to-thickness ratio for rectangular steel tube as using CFT column. A parametric study was performed taking width-to-thickness ratio of rectangular steel tube and compressive strength of concrete as the main parameter. The strength of concrete are selected to 30, 60, 90MPa. The non-linear analysis was adopted in order to take into account the effect of concrete strength. Finally, from the test and analysis results, the effect of increasing strength according to concrete strength and width-to-thickness of steel tube and plastic behavior of specimens were verified distinctly.

• 대한전자공학회논문지SD
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• 제40권9호
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• pp.638-643
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• 2003

Channel width dependence of hot-carrier effect in nMOSFET with shallow trench isolation is analyzed. $I_{sub}$- $V_{G}$ and $\Delta$ $I_{ㅇ}$ measurement data show that MOSFETs with narrow channel-width are more susceptible to the hot-carrier degradation than MOSFETs with wide channel-width. By analysing $I_{sub}$/ $I_{D}$, linear $I_{D}$- $V_{G}$ characteristics, thicker oxide-thickness at the STI edge is identified as the reason for the channel-width dependent hot-carrier degradation. Using the charge-pumping method, $N_{it}$ generation due to the drain avalanche hot-carrier (DAHC) and channel hot-electron (CHE) stress are compared. are compared.

• 한국공작기계학회논문집
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• 제16권4호
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• pp.45-50
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• 2007

In this paper, the FEM(Finite Element Method) has been applied to understand the geometrical characteristics and to analyze the stress of a helical gear. The helical gear is simulated and analyzed by adding many thin spur gear with helix angles and twist angles. Helical gears with different helix angle and face width have been studied. The results show that the root fillet stress is increased proportionally to helix angle and face width. Namely, as the face width increases, root fillet stress decreases, and as helix angle gets bigger, root fillet stress increases.