• Journal of the Society of Cosmetic Scientists of Korea
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• v.27 no.1
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• pp.53-72
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• 2001

Dry skin is caused mainly by the perturbation of stratum corneum lipids which affected by ageing, change of season, excess use of surfactant and the effect of disease like atopic dermatitis and psoriasis. Intercellular lipid structures in stratum corneum are responsible for the barrier function of mammalian skin. The major lipd classes that can be extracted from stratum corneum are ceramides, cholesterol and fatty acid, which make up approximately 50, 25, 10 percent of the stratum corneum lipid mass, respectively. Small amount of cholesterol sulfate, phospholipids, glycosylceramide and cholesterol esters are also present. Recent studies have shown that application of one or two these lipids to the perturbed skin delays barrier recovery; only equimolar mixtures allow normal recovery. We observed that barrier recovery rate was improved in hairless mouse by topical application of single neutral lipids (ceramide, free fatty acid, cholesterol) and lipid mixtures. Whereas the application of single lipid didn’t allows a significant enhancement comparing with normal barrier repair, the equimolar mixtures of 3 components(including synthetic pseudoceramide PC104) improved barrier repair, as assessed by the transepidermal water loss. At clinical study to the volunteers aged over sixty, skin dryness recuperated by the increase of moisture(capacitance) and the reduction of scaling. Utilization of physiologic lipid mixture containing natural ceramides or synthetic pseudoceramide could lead to new forms of topical therapy for the dryness and dermatoses(e.g., psoriasis, atopic dermatitis and irritant dermatitis).

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.3
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• pp.393-404
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• 2017

Side jet effect on the aerodynamic characteristics of a missile was investigated using experimental and computational methods. A couple of side jets were injected toward outward downstream at mid point of missile body. Cold air jet was used in the wind tunnel test, and cold and hot jet were used in the computation. Wind tunnel test was carried out with jet and without jet, and calculation was performed for three cases ; no jet, cold air jet, and hot mixture gas jet. From the comparison of measured and calculated data for all cases, two points could be deduced. Firstly, side jet made static stability to be unstable by increasing body normal force near the side jet exit and by decreasing tail normal force. Secondly, hot mixture gas had more significant effect on the static stability of a missile-type body than cold air jet.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.194-203
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• 2005

This study was peformed to investigate effect of feeding experimental mixture containing chitosan, hibiscus extract and L-carnitine on body weight and lipid metabolism in rats. Forty-eight male rats(Charles River CD) of eight weeks old and weighing $336.5{\pm}2.3g$ were raised for five weeks with high fat diet(40% fat as calorie) to induce obesity. After induction of obesity, rats weighing $560.4{\pm}5.6g$ were blocked into four groups according to body weight and raised for eight weeks with diet containing either 0.09%(+1D group), 0.9%(+10D group) or 4.5%(+50D group) of experimental mixture. Aspartate aminotransferase(AST) and alanine aminotransferase(ALT), total protein and albumin were normal levels in plasma. Body weight gain and epididymal fat pad weight were lower in experimental mixture groups than control group However, weights of perirenal fat pad and brown adipose tissue were not significantly different among all groups. There was no significant difference in plasma and hepatic lipid levels among all groups. Liver citrate lyase and camitine acyltransferase activities were not significantly different among all groups, however, citrate lyase activity was tended to be decreased with increasing experimental mixture level in diet. Fecal total lipid and total cholesterol excretions were highest in +50D group, and triglyceride excretion was highest in +1D group. in conclusion, intake of experimental mixture containing chitosan, hibiscus extract and L-camitine was effective in reducing body weight and body fat, and its inhibitory effects might lead to obesity improvement.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.575-580
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• 2006

This Study was designed to investigate the effects of Mixture of Bambusae Caulis in Liquamen and Bamboo Extract on the change of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal and cerebral ischemic rats. Experimental materials were as follows ; BE- 1 was Bamboo Extract (BE) extracted with 70% ethyl alcohol, BE-11 was BE extracted with distilled water at $121^{\circ}C$ for 30 min, BE-111 was BE extracted with distilled water at $121^{\circ}C$ for 3 hrs, MLC was mixture of Bambusae Caulis in Liquamen (BCL) and BE-111 mixed at the ratio of 1 to 100 (MLC100), 1 to 50 (MLC50), 1 to 20 (MLC20), 1 to 10 (MLC10), 1 to 5 (MLC5). The results were as follows , The Changes of BE- 1 on the rCBF and MABP in normal rats were not showed, BE- 11 significantly decreased rCBF in a dose-dependent manner Dut increased MABP in a dose-dependent manner. BE-111 increased rCBF in a dose-dependent manner, MLC significantly increased rCBF in a dose-dependent manner and increased MABP in a dose-dependent manner. rCBF was significantly and stably increased by MLC5 (1 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. As results above ; The present author thought that BE- 111 and MLC increased rCBF by dilating pial arterial diameter.

• Journal of the Korea Institute of Building Construction
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• v.21 no.4
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• pp.305-318
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• 2021

The aim of the research is providing the rheological performance range for manufacturing "mid-workability concrete". The mid-workability concrete means the normal strength range concrete mixture with high workability. Since there is not enough study or quantitative definitions on performance of the mid-workability concrete, in this research, the performance range for high workability of mid-workability concrete mixture using rheology. Because of the mixture characteristics of generally used normal strength concrete such as relatively high water-to-cement ratio and no SCMs, segregation of coarse aggregate should be prevent to achieve a successful high workability. From the experimental study in this research scope, 5 to 35 Pa.s of plastic viscosity was desirable to prevent segregation for nid-workability concrete, and general performance range with rheological parameters was provided.

• Speech Sciences
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• v.9 no.1
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• pp.39-47
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• 2002

This paper proposes an effective method to remedy the acoustic modeling problem inherent in the usual log-normal Parallel Model Composition intended for achieving robust speech recognition. In particular, the Gaussian kernels under the prescribed log-normal PMC cannot sufficiently express the corrupted speech distributions. The proposed scheme corrects this deficiency by judiciously selecting the 'fairly' corrupted component and by re-estimating it as a mixture of two distributions using data-driven PMC. As a result, some components become merged while equal number of components split. The determination for splitting or merging is achieved by means of measuring the similarity of the corrupted speech model to those of the clean model and the noise model. The experimental results indicate that the suggested algorithm is effective in representing the corrupted speech distributions and attains consistent improvement over various SNR and noise cases.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.12
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• pp.3326-3334
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• 1994

To theoretically predict knock occurrence in S. I. engine as a function of engine design and operating parameters, transient local temperature and pressure, mixture density of flame front in combustion period are calculated. We next determined normal combustion period and auto ignition period of end gas using the prediction method on occurrence of spark knock which we suggested. We predict knock occurrence in S. I. engine by comparing consecutively normal combustion period with the auto ignition period of end gas in combustion period. Engine design and operating parameters such as compression ratio, engine speed, spark timing, inlet temperature and pressure are taken into account in this calculations. The predicted result are well matched with the experimental results in turbocharged engine. Therefore, this method will provide the systematic guideline for designing engines in view of knocking limits.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.163-164
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• 2017

The paper is to investigate the effect of spreading of various kinds of oils on resistance to chloride attack of the normal strength concrete. Resistance to chloride attack was measured for 32 weeks and six different kinds of oils ere used. Test results indicated that resistance to chloride attack was improved in order of DSP, BD, ERBD and ERCO compared with that of Plain mixture due to filling effect of capillary pore by the use of oil.

• The Korean Journal of Applied Statistics
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• v.25 no.6
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• pp.1037-1047
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• 2012

The generalized linear mixed model(GLMM) is widely used in fitting categorical responses of clustered data. In the numerical approximation of likelihood function the normality is assumed for the random effects distribution; subsequently, the commercial statistical packages also routinely fit GLMM under this normality assumption. We may also encounter departures from the distributional assumption on the response variable. It would be interesting to investigate the impact on the estimates of parameters under misspecification of distributions; however, there has been limited researche on these topics. We study the sensitivity or robustness of the maximum likelihood estimators(MLEs) of GLMM for counts data when the true underlying distribution is normal, gamma, exponential, and a mixture of two normal distributions. We also consider the effects on the MLEs when we fit Poisson-normal GLMM whereas the outcomes are generated from the negative binomial distribution with overdispersion. Through a small scale Monte Carlo study we check the empirical coverage probabilities of parameters and biases of MLEs of GLMM.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.868-873
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• 2004

Renal dysfunction could be developed as the secondary disease of liver cirrhosis. Delayed or suppresed lipid peroxidation by the treatment with physiological active substances could be explained as the antioxidative and protective effect in tissue damage. In this study, we investigated an antioxidative effect and renal function improvement of Hovenia dulcis in liver fibrosis(cirrhosis) induced rats. The female Sprague-Dawley rats (180∼210 g) were divided into 3 groups (Normal, AC: CCl₄ mixture treated group, AC-HV: CCl₄ mixture+ Hovenia dulcis treated group) and renal damage was developed by CCl₄ mixture administration in 4 weeks (0.8 ㎖/rat). The tissue of kidney and liver and sera were used for quantitative measurement of enzyme activity, MDA and Hyp. The histological change and gene expression of collagen α1(III) mRNA and a1(IV) mRNA were observed by Masson's trichrome staining and RT-PCR. As a result, the clinical biochemical parameters of liver function (AST and ALT) in sera of AC-HV group showed significantly 46.4% and 104.8% lower (p<0.005), and the level of ALP and BUN as the parameter of protein urine and azotemia showed 17.8 % and 25.8 % lower than in AC group. In AC-HV group, the concentration of MDA in kidney and liver was decreased significantly 15.8% and 21.3% when compared with AC group (p<0.01 -0.005). The content of Hyp in kidney of AC-HV group is merely higher than in AC group, in contrast to liver tissue. The expression of collagen α1(III) mRNA and collagen α1(IV) mRNA was decreased in AC, but both of collagen mRNA in normal and AC-HV group expressed fast similar. More massive lipid droplets, thicker collagen fiber bundles in portal triads and more formation of portal central septum were observed in the liver of AC group than in AC-HV group. In conclusion, CCl₄ mixture intoxication could be developed not only liver fibrosis(cirrhosis) but also renal dysfunction by the massive lipid peroxidation and suppression of interstitial collagen and basement membrane collagen synthesis. And the water extract of Hovenia dulcis may be possessed the antioxidative and protective effect and improvement of kidney function in renal dysfunction induced rats.