• The Korean Journal of Applied Statistics
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• v.27 no.6
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• pp.923-932
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• 2014

The Hurdle model can to analyze zero-inflated count data. This model is a mixed model of the logit model for a binary component and a truncated Poisson model of a truncated count component. We propose a new hurdle model with a general heterogeneous random effects covariance matrix to analyze longitudinal zero-inflated count data using modified Cholesky decomposition. This decomposition factors the random effects covariance matrix into generalized autoregressive parameters and innovation variance. The parameters are modeled using (generalized) linear models and estimated with a Bayesian method. We use these methods to carefully analyze a real dataset.

• Journal of the Korean Home Economics Association
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• v.35 no.3
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• pp.275-286
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• 1997

The effects of water-and oil-repellent finishes on the surface characteristics of polyester fabrics were investigated in this study. Three kinds of fluoropolyment were selected as water=and oil-repellent finishing agents. The effects of water-and oil-repellent finishes were determined by the water repellency and oil repellency. The surface properties of untreated and treated polyester fabrics were evaluated with respects to crease resistance, contact angle and wicking time. The results of this study were as follows: 1. The polyester fabrics treated with fluoropolymers showed much higher water repellency and oil repellency than those of untreated polyester fabrics. Water-and oil-repellency of fabrics were increased with the crystallinity and the hydrophobic-hydrophillic components of fluoropolymers. 2. Water repellency of fabrics treated with fluoropolymer with hydrophobic components was the highest. Oil repellency of fabrics treated with fluoropolymer with high crystallinity was the highest. Water-and oil-repellency of fabrics treated with fluoropolymer with hydrophyllic components was low comparatively. 3. The crease resistance of polyester fabrics treated with fluoropolymer nearly approached to that of untreated polyester fabric. 4. The water-and oil-repellent finishes improved contact angle markedly. Especially the contact angle of ployester fabric treated with fluropolymer with hydrophobic component was the biggest. 5. The wicking time of polyester fabric treated with fluropolymer with hydrophobic component was the longest.

• Wind and Structures
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• v.27 no.2
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• pp.123-136
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• 2018

The effects of steep and shallow hills on a stationary tornado-like vortex with a swirl ratio of 0.4 are simulated and quantified as Fractional Speed Up Ratios (FSUR) at three different locations of the vortex with respect to the crests of the hills. Steady state Reynolds Averaged Naiver Stokes (RANS) equations closed using Reynolds Stress Turbulence model are used to simulate stationary tornadoes. The tornado wind field obtained from the numerical simulations is first validated with previous experimental and numerical studies by comparing radial and tangential velocities, and ground static pressure. A modified fractional speed-up ratio (FSUR) evaluation technique, appropriate to the complexity of the tornadic flow, is then developed. The effects of the hill on the radial, tangential and vertical flow components are assessed. It is observed that the effect of the hill on the radial and vertical component of the flow is more pronounced, compared to the tangential component. Besides, the presence of the hill is also seen to relocate the center of tornadic flow. New FSUR values are produced for shallow and steep hills.

• Journal of Oriental Neuropsychiatry
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• v.14 no.2
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• pp.43-59
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• 2003

Object : This study was designed to assess the protective effects of Jowiseungchungtang on cognitive decline of the patients with early DAT[Dementia of Alzheimer Type]. Method : 15 patients with early DAT and 10 healthy elderly subjects were measured by using auditory ERP and K-DRS, and after 9 months again. During 9 months the patients with early DAT were administered with Jowiseungchungtang. Result : 1. The score of K-DRS increased in two group but it was not significant. 2. The latency of ERP P300 component increased in 2nd test of the normal group, but did not increase in 2nd test of patients group. 3. The amplitude of ERP P300 component showed the significant difference in electrode location in patients group, but it did not show any typical property. Conclusion : The results suggest that Jowiseungchungtang may have protective effects on cognitive decline in the patients with early DAT.

• Journal of Oriental Neuropsychiatry
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• v.16 no.1
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• pp.43-66
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• 2005

Object : This study was designed to asses the protective effects of Kunneo tang on cognitive decline of the patients with early DAT. Method : Before administered with Kunneotang, 16 patients with early DAT were measured by auditory ERP, MMSE-K and K-DRS. During 12 months the patients with early DAT were administered with Kunneotang. After 12months the patients were measured by the same examinations again. Result : 1. The total score of MMSE-K decreased but it was not significant. 2. The total score of K-DRS increased but it was not significant. Among the five criteria(attention, memory, initiation/perseveration, construction, conceptualization), Initiation/perseveration score signifcantly decreased and there were no significant differences in the other scores. But, memory mean score had a tendency to increase. 3. The latency of ERP P300 component increased but it was not significant and the amplitude of ERP P300 component showed the significant difference. Conclusion : The results suggest that Kunneotang may have protective effects on cognitive decline in the patients with early DAT.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.4_2
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• pp.627-635
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• 2020

In this study, the optimal support span determination of pipeline system was carried out in consideration of the effects of seismic loads. The theoretical support and structural analysis were used to determine the optimal support span of piping system according to pipe diameter using theoretical and structural deflection criteria. The reliability of the analysis results was secured by comparing the structural and theoretical results. In particular, the optimum support span of piping system was obtained by considering the effects of seismic load, and the optimal support span of pipe diameter and piping system tended to be proportional to each other. When considering the effects of earthquakes on different pipe diameters(300~2,500mm), the span length is reduced by up to 48% at the allowable stress criterion, and the pipe span length is reduced by up to 5.9% at the deflection criterion. It can be seen that the effect of the seismic load on the determination of the piping span length has a greater effect on the stress than the displacement.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.346-352
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• 2005

The chemical characteristics, enzymatic saccharification, and ethanol fermentation of autohydrolyzed lignocellulosic material that was exposed to steam explosion were investigated using bagasse as the sample. The effects of the steam explosion on the change in pH, organic acids production, degrees of polymerization and crystallinity of the cellulose component, and the amount of extractive components in the autohydrolyzated bagasse were examined. The steam explosion decreased the degree of polymerzation up to about 700 but increased the degree of crystallinity and the micelle width of the cellulose component in the bagasse. The steam explosion, at a pressure of 2.55 MPa for 3 mins, was the most effective for the delignification of bagasse. 40 g/L of glucose and 20 g/L of xylose were produced from 100 g/L of the autohydrolyzed bagasse by the enzymatic saccharification using mixed cellulases, acucelase and meicelase. The maximum ethanol concentration, 20 g/L, was obtained from the enzymatic hydrolyzate of 100 g/L of the autohydrolyzed bagasse by the ethanol fermentation using Pichia stipitis CBS 5773; the ethanol yield from sugars was 0.33 g/g sugars.

• International Journal of Highway Engineering
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• v.14 no.4
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• pp.51-61
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• 2012

PURPOSES : This study deals with the working life of polymer concrete, which is typically used as a repair or overlay material for portland cement concrete pavements. METHODS : In the scope of this study, laboratory testing was conducted on fresh MMA modified UP polymer concrete, which uses an MMA monomer for viscosity adjustment and strength improvement of UP resin. The experimental variables were temperature (-20 to $+20^{\circ}C$) and binder components (MMA, MEKPO, and DMA). RESULTS : The result showed that the optimum binder ratios for polymer concrete production were 12, 11, and 10 wt.% when the MMA contents were 20, 30, and 40 wt.%, respectively. The working life of polymer concrete depending on temperature and binder components could be expressed by a logarithmic functional formula. The coefficient of variation for each binder component was the highest for DMA content while the lowest for MEKPO content. Also, the contents of each binder component for ensuring the working life of 60 minutes were proposed. CONCLUSIONS : Ultimately, the present study derived a linear regression equation estimating 60 minutes working life based on the setting times of each binder component.

• Korean Journal of Pharmacognosy
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• v.10 no.1
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• pp.17-22
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• 1979

The investigation is involved with the effect of Capsicum component on the drug metabolism. To investigate the effects of Capsicum component on, in vivo, drug metabolism in rat, Capsicum acetone extract was given intraperitoneally to mice or rats. The duration of loss of righting reflex was determined as hexobarbital sleeping time in mice. Plasma hexobarbital concentration was also measured by Brodie's method. The rats were pretreated with Capsicum extract acutely or chronically. As the results, hexobarbital sleeping time and plasma hexobarbital concentration were increased by 31.2% and 12.3% in acute study, whereas were decreased by 27.5% and 23.0% in chronic study. An attempt was made to determine if there were any influences on enzyme activities in rats pretreated with Capsicum extract chronically. Microsomal fraction was isolated from rat liver and quantity of cytochrome $P_{450}$ and $b_5$ in the microsomal fraction were determined by Omura's method. It was found that the quantity of cytochome $P_{450}$ was increased by 22.4%. The results suggest that microsomal drug metabolizing enzyme may be induced by chronic administration of Capsicum component, whereas it may be inhibited by acute administration of Capsicum component.

• The Journal of the Korea Contents Association
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• v.9 no.1
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• pp.159-166
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• 2009

In this paper, we analyse the noise robustness of MLPs(Multilayer perceptrons) through deriving the probability density function(p.d.f.) of output nodes with additive input noises and the misclassification ratio with the integral form of the p.d.f. functions. Also, we propose linear preprocessing methods to improve the noise robustness. As a preprocessing stage of MLPs, we consider ICA(independent component analysis) and PCA(principle component analysis). After analyzing the noise reduction effect using PCA or ICA in the viewpoints of SNR(Singal-to-Noise Ratio), we verify the preprocessing effects through the simulations of handwritten-digit recognition problems.