• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.550-553
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• 2001

In this study, unity current gain frequency f$\_$T/ of GaAs MESFET is predicted with different temperatures up to 400 $^{\circ}C$. Temperature dependence parameters of the device including intrinsic carrier concentration n$\_$i/ effective mass, depletion width are considered to be temperature dependent. Small signal parameters such as gate-source, gate dran capacitances C$\_$gs/ C$\_$gd/ are correlated with transconductance g$\_$m/ to predict the unity current gain frequency. The extrinsic capacitance which plays an important roles in high frequency region has been taken into consideration in evaluating total capacitance by using elliptic integral through the substrate. From the results, f$\_$T/ decreases as the temperature increases due to the increase of small signal capacitances and the mobility degradation. Finally the extrinsic elements of capacitances have been proved to be critical in deciding f$\_$T/ which are originated from the design rule of the device.

• Journal of the Korean Chemical Society
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• v.9 no.1
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• pp.8-15
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• 1965

Justifications for the use of ${\sigma}$ and Y as independent potential energy variables in the general equation have been reviewed and some mechanistic significances of the relationship discussed. Analysis of the activation parameters for the solvolysis of benzyl chlorides in ethanol-water mixture showed that there are two distinct series of substrate constants ${\alpha}'$, which can be correlated linearly within a series with the substituent constants ${\sigma}$ conforming to the generally accepted concept of change in mechanism from $S_N1$ to $S_N2$.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.161-168
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• 2006

Genetic parameters for linear type and composite traits were estimated by using Bayesian inference via Gibbs sampling with a multiple threshold animal model in Holstein cows. Fifteen linear type traits and 5 composite traits were included to estimate genetic variance and covariance components in the model. In this study, 30,204 records were obtained in the cows from 305 sires. Heritability estimates for linear type traits had the estimates as high as 0.28~0.64. Heritability estimates for composite traits were also high, when the traits were assumed to be categorical traits. Final score was more correlated with the composite traits than with the linear type traits.

• Journal of the Korea Society for Simulation
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• v.14 no.3
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• pp.129-136
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• 2005

We develop a variance reduction technique applicable in one simulation experiment whose purpose is to estimate the parameters of a first order linear model. This method utilizes the control variates obtained during the course of simulation run under Schruben and Margolin's method (S-M method). The performance of this method is shown to be similar in estimating the main effects, and to be superior to S-M method in estimating the overall mean response in a given model. We consider that a proposed method may yield a better result than S-M method if selected control variates are highly correlated with the response at each design point.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.3
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• pp.52-60
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• 1993

Fluttering ghost which is the most severs picture impairment in mobile TV reception under multipath fading environments can be detected by measuring the dynamic variation of the synchronizing pulse timing. And also, the occurrence-stucture of fluttering ghost are directly correlated with the multipath parameters. This paper describes the quantitative evaluating method of the mobile TV pictures impaired by multipath parameters by means of the spectral analysis of synchronizing timing fluctuation. The ghost-flutter curve derived from the spatial amplitue spectrum of synchronizing pulse timing fluctuation express well the spatial variation characteristic, and it has been found to be the quantitative evaluating measure of picture impairment in mobile reception. A correspondence between the ghost-flutter curve (and/or index) and picture quality opinion test results is established.

• Journal of Nutrition and Health
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• v.33 no.5
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• pp.524-531
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• 2000

This study was conducted to investigate the basal leptin concentrations in normal(n=17, BMI 20-25, obesity index 90-110%) and overweight(n=13, BMI > 25, obestity index > 120%) Korea young aldult males, and correlation between leptin concentrations, nutrients intake, anthropometry and other biochemical parameters. Nutritional status, serum leptin and biochemiccal parameters were evaluated based on 24hr-dietary records, anthropometric measurement and blood analysis. Obesity index were 138% and 101% in overweight and normal group, respectively. Serum leptin concentration was higher in overweight group than that in normal group (8.65$\pm$ 9.41 vs 2.06 $\pm$ 1.19, p<0.05). Serum triglyceride, HDL-cholesterol and insulin concentrations were higher in overweight group than in normal group(p<0.05). Nutrients intakes was not different between two group. The leptin concentrations were correlated with body weight(p<0.001), BMI(p<0.05), obesity index(p<0.05), waist circumference(p<0.05), animal lipid intake(p<0.05)in overweight group.

• YAKHAK HOEJI
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• v.44 no.5
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• pp.424-431
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• 2000

A biopharmaceutics drug classification system for correlation between in vitro dissolution and in vivo bioavailability is proposed based on recognizing that drug dissolution and gastrointestinal permeability are the fundamental parameters controlling the rate and extent of drug absorption. The objective of this study was to assess whether in vitro dissolution profiles of immediate-release beta-blocker tablets can be correlated with intestinal membrane permeability and/or in vivo bioavailability In vitro dissolution of the beta-blocker tablets was examined using KP VII Apparatus II methods at various pH. Intestinal membrane permeability was determined in vitro using the diffusion chamber method. Bioavailablity parameters were cited from literatures. The dissolution profiles did not accurately represent the in vivo bioavailablity However there were good correlations between intestinal membrane permeability and log P (noctanol/buffer). The correlations obtained in this study indicated that in vitro diffusion chamber method could be used to predict intestinal absorption in vivo.

• Journal of the Korean Physical Society
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• v.73 no.12
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• pp.1849-1854
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• 2018

The present study aims to investigate the feasibility of using a simple nonlinear acoustic method for the assessment of bone status and osteoporosis in trabecular bone. Correlations of linear and nonlinear ultrasound parameters with the apparent bone density were obtained in 32 bovine femoral trabecular bone samples. Highly significant positive correlations were observed between the apparent bone density and the two linear ultrasound parameters, the speed of sound (SOS) and the normalized broadband ultrasound attenuation (nBUA), with Spearman's correlation coefficients of r = 0.85 and 0.77. In contrast, the apparent bone density was found to be negatively correlated with the nonlinear ultrasound parameter introduced in the present study, the logarithmic difference between the power spectrum levels of the fundamental frequency and the second harmonic (PSL1-PSL2), with the highest correlation coefficient of r = -0.92. These results suggest that the PSL1-PSL2, in addition to the SOS and the nBUA, may be useful for the assessment of bone status and osteoporosis.

• Advances in nano research
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• v.17 no.4
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• pp.293-299
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• 2024

In this paper, the simplified ordinary differential equations are solved with shooting technique. The concentration and microorganism slip boundary conditions are implemented. Non-linear expression is reduced via non-dimensional variables. The microorganism distribution declines by increasing Lewis number and microorganism slip parameter. Behavior of distinct influential parameters viz: Eckert number, bioconvected Lewis number, bioconvected Peclet number, microorganisms slip parameter are investigated graphically and analyzed for concentration and microorganism. Enhanced concentration is correlated with energy activation. An acceptable agreement is reached when the numerical technique is compared to the existing literature. The magnitude of microorganism transfer rate shows decreasing behavior for higher values of slip parameters.

• Journal of Nutrition and Health
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• v.42 no.4
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• pp.338-349
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• 2009

We aimed to evaluate the effect of nutrition education program on nutrition knowledge, dietary behavior, dietary intakes and anthropometric parameters in primary school children. Eighty five 4th grade children (boys = 43, girls = 42) were enrolled in the intervention program for 5 months. The subjects were asked to fill out a questionnaire about nutrition knowledge and dietary behavior two times, at the baseline and after completion of the program. Dietary intake information was collected from participants using a 3-day food record and their anthropometric parameters were measured. Upon completion of the intervention program, both nutrition knowledge and dietary behavior scores were significantly improved in all subjects. Energy intake was increased from 1,571.9 kcal to 1,734.1 kcal with significant improvements in nutrient density for protein, Ca, P, K, vitamin A and niacin. While subjects' height, weight, lean body mass and soft lean mass were significantly increased during the program, significant decreases were observed in the rohrer index, percent body fat, waist-hip ratio and body fat mass. The changes in nutrition knowledge scores were positively correlated with the changes in dietary behavior scores, micronutrient intakes and anthropometric parameters. These results indicate that enhancement of nutrition knowledge through well-planned long-term nutrition education program is effective not only for the improvement of dietary behaviors and dietary intakes but also for the positive changes in anthropometric parameters among primary school children.