• Interaction and multiscale mechanics
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• v.6 no.3
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• pp.287-300
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• 2013

In this paper, the effect of impulsive line on the propagation of shear waves in non-homogeneous elastic layer is investigated. The rigidity and density in the intermediate layer is assumed to vary quadratic as functions of depth. The dispersion equation is obtained by using the Fourier transform and Green's function technique. The study ends with the mathematical calculations for transmitted wave in the layer. These equations are in complete agreement with the classical results when the non-homogeneity parameters are neglected. Various curves are plotted to show the effects of non-homogeneities on shear waves in the intermediate layer.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09b
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• pp.45-48
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• 2003

We propose some properties of Bayesian fuzzy hypotheses testing by revision for prior possibility distribution and posterior possibility distribution using weighted fuzzy hypotheses H$\sub$0/($\theta$) versus H$_1$($\theta$) on $\theta$ with loss function.

• Journal of the Korean Data and Information Science Society
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• v.20 no.1
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• pp.191-202
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• 2009

In this study, we drive the one dimensional marginal transform function, probability density function and probability distribution function for the random variables $T_{{\xi}N}$ (Time taken by the servers during the vacations), ${\xi}_N$(Number of vacations taken by the servers) and ${\eta}_N$(Number of customers or units arrive in the system) by controlling the variability of two random variables simultaneously.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.672-676
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• 2002

In this paper, a reliability-based design optimization method, which enables the determination of optimum design that incorporate confidence range for structures, is studied. Response surface method and Monte Carlo simulation are utilized to determine limit state function. The proposed method is applied to the I-type steel structure for reliability based optimal design.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1989.10a
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• pp.19-24
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• 1989

The electron energy distribution function in mercury discharge positive columns are calculated numerically from the Boltzmann eqation under a set of parameters, such as the electron temperature to. the atomic temperature Tw. the electron number density no. and the electric field E. Especially, using the approximation that collision cross sections only depend on the energy, the calculated electron energy distribution function was shown that it falls off rapidly in the high energy tail.

• Communications for Statistical Applications and Methods
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• v.6 no.3
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• pp.729-748
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• 1999

In this paper we present combined estimator of capture-recapture and line transect model using bivariate detection function and detection probability according to objects being in cluster population. Here bivariate detection function use distance and cluster size. The simulation shows that combined estimator approaches the more true value the larger size parameter. Therefore this estimator using the bivariate detection function is more efficient in estimate the population size and density by size parameter.

• International Journal of Reliability and Applications
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• v.14 no.2
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• pp.107-114
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• 2013

Modelling of failures is an important element of reliability modelling. Empirical modelling approach suitable for complex item is explored in this paper. First step of the empirical modelling approach is to plot hazard function, density function, Weibull probability plot as well as cumulative intensity function to see which model fits best for the given data. Next step of the empirical modelling approach is select appropriate model for the data and fit the parametric model accordingly and estimate the parameters.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.2
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• pp.9-18
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• 1986

For identification and apportionment of sources emitting particulate matters in environment, the multi-elemental characterization of size-density fractionated particulate matters was carried out. Eight types of samples were tested; soil, flyash released from burning of bunker-Coil, diesel oil, coal, and soft coal, urban road-way dust, urban dust fall, and airborne particulate matter. The fractions of particulate matters obtained by heavy liquid separation methos with a series of dichloromethane-bromoform were then analyzed using atomic absorption spectrophotometry for Ni, Cr, Cu, An, Fe, Al, and Mg. Each sample showed a different concentration profile as a function of density, and a number of useful conclusions concerning characterization of elemental distribution were obtained. From the density distributions of elements in soil, the maximum value was found for all elements in the density range of 2.2 $\sim 2.9g.cm^{-3}$, including the density of $SiO_2$. However, the distribution of metallic compounds with the density lower than $2.2g.cm^{-3}$ was prevalent in urban roadway dust, urban dust fall, and airborne particulate matter. And the density distribution curves of these urban dusts also have the higher distribution at the density of 2.2 - 2.9g.cm^{-3}$, including the density of wind-blown silica. This tendency generally was prevalent in the natural source elements, such as Al, Fe, Mn, and Mg. The maximum values were found in the density ranges of 1.3 $\sim 2.2g.cm^{-3}$ from the density distribution of elements in oil fired flyash. These distributions of anthropogenic source elements, such as Zn, Ni, Cu, and Cr were higher predominately than those of natural source elements. And the higher distribution was found in the density range of $2.2 \sim 2.9g.cm^{-3}$ from the density distribution of elements in coal and soft-coal fired flyash. These distributions showed similar patterns to soil. But anthropogenic source elements somewhat predominated at the density ranges of $1.3 \sim 2.2g.cm{-3} and 2.9g.cm^{-3}$ to soil. Therefore the higher distribution of anthropogenic source elements in the density ranges of $1.3 \sim 2.2g.cm^{-3} and 2.9g.cm^{-3}$ was considered as anthropogenic origin.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.120-131
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• 2009

This study measured the centripetal force and effective scope of the population spread from urban center and subcenters in order to diagnose the urban spatial structure of the formation of a multicentric city structure in Busan. The study analyzed the variability of the determination coefficient value (R square) with a negative exponential function derived from the population density model by extending the circular region into 5-km units. The aim of this study was to measure changes in the effective scope of the population centripetal force of the urban center and subcenter in 5-year intervals from 1995 to 2005 using census data. The explanatory adequacy of the population density function was examined with the bias of the function to calculate the distance error between the real location of the urban center and the optimal location, according to the population density function. To summarize the results, the value for the area of Jungangdong showed a continuous reduction, whereas Seomyeon (Bujeondong) maintained explanatory adequacy without a large change. As a whole, Busan was in the process of continuous diversification, in spite of its reduced population. Therefore, it appears necessary to strengthen the function of the urban center and subcenter and to supply adequate dwelling zones close to downtown to form a more efficient urban spatial structure. The results of the present study will be utilized as basic data for the formulation of a political approach to the efficient reorganization of spatial structure by correlating concrete spatial information with the population variability of Busan's urban center and subcenter.

• Journal of Nutrition and Health
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• v.37 no.9
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• pp.786-793
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• 2004

Women with menopause or rats with ovariectomy is associated with increased body weight, body fat and insulin resistance, which are components of metabolic syndrome. Increased prevalence of metabolic syndrome after menopause might be associated with mitochondrial dysfunction, since mitochondrial oxidative and phosphorylation activity is strongly correlated with insulin sensitivity. Although estradiol replacement prevents the metabolic syndrome, harmful effect of estradiol hampers the casual usage to prevent the metabolic syndrome. It has been reported that genistein has a mild estrogenic activity, decreases fat mass in mice and has an antidiabetic role in diabetic rats. Although insulin resistance is closely related to mitochondrial functions, there has not been yet any study in regard to the effect of dietary genistein on mitochondrial function in the insulin resistant female subjects induced by ovariectomy or similar situation. The present study investigated whether the supplementation of genistein in the high fat diet affected the mitochondrial function of high fat fed ovariectomized rats. Female Sprague Dawley rats (8 weeks old) were assigned to the following groups: sham-operated+ high fat diet (S, n=6); sham-operated + high fat diet with 0.1% genistein (S + G, n=7); ovariectomized + high fat diet (OVX, n=8); ovariectomized + high fat diet with 0.1% genistein (OVX+ G, n=8). Ovariectomy significantly increased body weight compared with S group. Genistein consumption in ovariectomized (OVX + G) rats decreased body weight gain compared with OVX rats. Liver weights were increased by ovariectomy. The hepatic mitochondrial protein density expressed as mg per g liver was lower in the OVX group than in the S group. However, OVX + G group showed the increased mitochondrial protein density similar to the level of S group. When mRNA levels of genes related to mitochondria such as peroxisome proliferator-activated receptor ${\gamma}$ coactivator 1 (PGC-1) and cytochrome c oxidase subunit III (COX III) were measured, there were decreases in the mRNA levels of PGC-1 and COX III in S + G, OVX and OVX + G group. The activity of cytochrome c oxidase was not different between groups. We could observe the decrease in succinate dehydrogenase (SDH) activity per g liver in OVX rats. Genistein supplement increased SDH activity. In conclusion, genistein supplementation to the OVX rats enhanced mitochondrial function by increasing mitochondrial protein density and SDH activity. The improvement in mitochondrial function by genistein can contribute to the improvement in metabolic syndrome.