• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.2
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• pp.208-214
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• 1986

To establish the evaluation of the fatigue crack growth behavior in 5083-O aluminum alloy, constant load-amplitude fatigue crack growth tests were carried out under the small scale yielding conditions. Crack length and closure of this material were measured by the compliance method using a clip-on gage. The main results obtained as follows: The fatigue crack growth rate against stress intensity factor range .DELTA.K exhibits the trilinear form with two transitions at the growth rate 5.5*10$^{-6}$ and 5.5*10$^{-5}$ mm/cycle, in the so-caled Region II. The trilinear form appears still in the plot of growth rate versus effective stress intensity factor range .DELTA. $K_{eff}$. Stress ratio R affects the relationship of crack growth rates versus .DELTA.K but does not affect the reation of crack growth rate versus .DELTA. $K_{eff}$. The experimental results indicate that the effective stress intensity range ratio U depends on the maximum stress intensity factor $K_{max}$, but not on the stress ratio R.o R.R.

• Fashion & Textile Research Journal
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• v.7 no.2
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• pp.162-168
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• 2005

The pictures of design details, such as collar type, sleeve type, skirt type, and skirt length, and color tone were evaluated by 377 persons in terms of sensibility and emotion. The data were analyzed by SPSS using ANOVA and Factor analysis to find out the most effective types of details on consumer's sensibility and emotion, and the methods were introduced. The most effective type is skirt length on sensibility and emotion of women's dress. The second type is different according to sensibility and emotion. Sensibility and emotion were composed of three concept: contemporary, mature and character. Sleeve type is second determinant to contemporary concept, and color tone is to mature concept, collar type is to character concept. 41 each details of design were positioned into 3D-concept space to connect each detail type and fashion concept of women's dress.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.594-601
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• 2019

A true MSEW abutment is an abutment type that directly supports the load of a superstructure. Metal strips, which are in-extensile reinforcements, should be used to minimize abutment deformation. A study to derive the application conditions of a True MSEW abutment was carried out by Zevogolis(2007). As a result, the pullout factor of safety of the uppermost reinforcement was estimated to be the smallest. Therefore, the pullout factor of safety of the uppermost reinforcement is the most important design factor. Parameter analysis was conducted with the abutment length, abutment heel, and abutment height as variables. The pullout factor of safety increased with increasing abutment length and abutment heel length. This is because the contact area increases and the superstructure is dispersed as the abutment length and abutment heel length increase. The pullout factor of safety converges at an abutment length of 1.2m and an abutment heel length of 0.9m. This is because the effective length of the reinforcement is reduced due to the increase in contact area. On the other hand, the extension of the superstructure will increase if the abutment length and abutment heel length are increased excessively. In addition, earth-volume is increased if the abutment height increases excessively. This acts as an upper load on the MSE wall. Therefore, it needs to be examined carefully.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.749-755
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• 2023

A new approximation method was proposed for treating the non-resonant spatial self-shielding effects of double heterogeneous region such as the double heterogeneous effect of VHTR fuel compact in the thermal energy range and that of BP compact with BISO. The method was developed based on the effective homogenization method and a spherical unit cell model with explicit coated layers and a matrix layer. The self-shielding factor was derived from the relation between the collision probabilities for a double heterogeneous compact and the effective cross section for the homogenized compact. First, the collision probabilities and transmission probabilities for all layers of the spherical model were calculated using conventional collision probability solver. Then, the effective cross section for the homogenized sphere cell representing the homogenized compact was obtained from the transmission probability calculated using the probability density function of a chord length. The verification calculations revealed that the proposed method can predict the self-shielding factor with a maximum error of 2.3% and the double heterogeneous effect with a maximum error of 200 pcm in the typical VHTR problems with various packing fractions and BP compact sizes.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.1 no.1
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• pp.28-34
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• 1990

In this paper we discussed the theoretical antenna factor of a cylinderical dipole antenna. The Current distribution on a dipole antenna was analyzed by the method of moment, and this solu- tion is used for calculating the effective length and antenna factor of the half-wave dipole in free space.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.178-183
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• 1998

This paper examines the crack growth behavior of 7075-T651 and 5052-H32 aluminum alloys for variable load within tensile load range condition. The cantilever beam type specimen with a chevron notch is used in this study. The crack growth and closure are investgated by compliance method. The applied initial stress ratio is R=0.3 and variable load are R=0.65, 0.46. Crack length, stress intensity factor range, ratio of effective stress intensity factor range and crack growth rate etc. are inspected with fracture mechanics estimate.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.5
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• pp.531-539
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• 1991

We develop an analytical model of the static and the dynamic characteristics of amorphous silicon thin film transistors (a-Si TFTs) in order to incorporate into a widely used circuit simulator such as SPICE. The critical parameters considered in our analytical model of a-Si TFT are the power factor (XN) of saturation source-drain current and the effective channel length (L') at saturation region. The power factor, XN must not always obey so-called

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.5
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• pp.89-99
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• 2015

In this research, 1,032 data of precise safety inspection from 2004 to 2013 are gathered and constructed for finding effective safety inspection systems. Items are extracted from constructed data and factors for typology are decided with statistical method such as principle component analysis and cluster analysis. For factor decision, we extruded independent characteristics such as morphological and geographical characteristic, and deleted items which can be expressed by combination of independent characteristics. Four factors such as total storage, watershed ratio, levee length ratio, and spillway length ratio are extracted in this process. In cluster analysis, levee length ratio is excluded because it is not separated as cluster. Finally nine types of agricultural reservoir are extruded by total storage, watershed ratio, and spillway length ratio with frequency analysis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.2
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• pp.243-252
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• 1987

The propagation and closure behavior of surface crack initiated at a sharply notched specimens were investigated in 5083-H113 aluminium alloy under constant amplitude of tension load by the unloading elastic compliance method. The crack shape (aspect ratio) was found to be approximately semicircular during the crack was being small and to be changed to semi-elliptical during it was being long. The propagation rate of a surface crack initiated from notch root decelerated with increasing crack length when the crack was small and then accelerated when it was large. The effect of stress ratio was large in lower .DELTA.K range, but the effective stress intensity factor range .DELTA.K$_{eff}$ was found to diminish the difference of the crack propagation rate. By considering the increase in crack closure stress with crack length and examining the microphotographs, plasticity-induced and roughness-induced crack closure mechanisms were predominant in the range of this study.y.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.67-74
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• 1999

Self-Boring Pressuremeter Test(SBPT) is known to be the most effective in-situ test method which can reliably determine consolidation characteristics as well as deformation modules and untrained shear strength. In order to derive the coefficient of consolidation using SBPT results it is necessary to obtain the dissipation behavior from the pore pressure change with time during constant radial strain(generally 10%) and to derive the reliable time factor(Τ) from the analytical method which considers the real in-situ conditions. As previous studies on time factor are based on the assumptions of plane strain condition that the membrane of SBP is infinite, of untrained condition during the expansion of the probe and of elastic soil behavior during consolidation, these analyses can't consider the real boundary conditions and the real soil behaviour. In this study, consolidation analysis similar to real in-situ conditions including test procedure is conducted using finite element program which employs MCC model and Biot theory. Time factor considering the effects of finite membrane length, the total pressure change during consolidation and partial drainage is proposed and compared with previous results.