• 대한지역사회영양학회지
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• 제2권1호
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• pp.33-43
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• 1997

In order to investigate the dietary intakes and physical characteristics in college women smokers, interviews using questionnaires were done on 33 smokers and 42 nonsmokers residing in seoul area. General living habits, dietary habits, food consumption frequency and nutrient intake by quick estimation were investigated through direct interviews with subjects. Subjects height, weight and blood pressure were measured, and body fat percentage were statistically analyzed using Bio-electrical Impedence Fatness Analyzer(GIF-891). All data were statistically analyzed by SAS PC package program ; percentage or mean and standard error were examined for each item, and the significant difference was evaluated by chi-square test or Student's t-test at $\alpha$=0.05. In the analysis of taste and food preference, smokers consumed larger amount of alcohol and coffee than nonsmokers ; they also disliked sweet taste. The results of food consumption frequency data also showed that smokers consumed less fish, milk and fruits but consumed more instant foods than nonsmokers. As a result of anthropometric measurements, height, age, and 패요 fat percentage showed no difference, but there was a significant difference in weight, BMI, systolic blood pressure, and diastolic blood pressure. Energy intake in nonsmokers was 1640 ㎉/day(CHO : Pro : Fat=66.0 : 14.7 : 19.3), in smokers. Intakes of calcium, iron, vitamin C, vitamin A, vitamin B1, vitamin B2, and niacin in smokers were not significantly different from those of nonsmokers.

• 한국자동차공학회논문집
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• 제1권3호
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• pp.74-82
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• 1993

Optimal designs of a 3-point and a 4-point engine mount system are presented for reducing the idle shake of a Front Wheel Drive(FWD) vehicle. Design variables used in this study are the locations, the angles and the stiffness of an engine mount system. The goal of the optimization is minimizing the transmitted force without violating the constraints such as static weight sag, resonant frequency and side limits of design variables. The Augmented Lagrange Multiplier(ALM) Method is used for solving the nonlinear constrained optimization. The generalized Jacobi and the impedence method are employed for a free vibration analysis and a forced response analysis. The trend of analysis results well meet that of the experimental results. The optimization results reveal that the 4-point system transmits less torque than the 3-point system. It is also found from the design sensitivity analysis that the vibration characteristics of the 4-point system is less sensitive than those of the 3-point system.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.145-145
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• 2011

Recently, multi-hole electrode RF capacitively coupled plasma discharge is being used in the deposition of microcrystalline silicon for thin film solar cell to increase the speed of deposition. To make efficient multi-hole electrode RF capacitively coupled plasma discharge, the hole diameter is to be designed concerning the plasma parameters. In past studies, the relationship between plasma parameters such as pressures and gas species, and hole diameter for efficient plasma density enhancement is experimentally shown. In the presentation, the relationship between plasma deriving frequency and hole diameter for efficient multi-hole electrode RF capacitively coupled plasma discharge is shown. In usual capacitively coupled plasma discharge, plasma parameter, such as plasma density, plasma impedence and plasma temperature, change as frequency increases. Because of the change, the optimum hole diameter of the multi-hole electrode RF capacitively coupled plasma for high density plasma is thought to be modified when the plasma deriving frequency changes. To see the frequency effect on the multi-hole RF capacitively coupled plasma is discharged and one of its electrode is changed from a plane electrode to a variety of multi-hole electrodes with different hole diameters. The discharge is derived by RF power source with various frequency and the plasma parameter is measured with RF compensated single Langmuir probe. The shrinkage of the hole diameter for efficient discharge is observed as the plasma deriving frequency increases.

• 센서학회지
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• 제8권2호
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• pp.108-114
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• 1999

표면 탄성파 가스센서는 소자의 크기가 작고, 값이 싸며, 가스에 대한 감도가 매우 높고 소자의 신뢰도가 높은 장점을 갖고 있다. 본 연구에서는, $LiTaO_3$ 단결정 압전기판 위에 이중지연선을 갖는 표면 탄성파 $NO_2$ 가스센서를 설계 및 제작하였다. 제조된 IDT의 커패시턴스는 79.3MHz의 주파수에서 326.34pF였다. 임피던스 매칭이 된 IDT의 반사손실은 79.3MHz의 주파수에서 최대인 -16.74dB로 나타났다. SAW 발진기를 성하여 고주파증폭기의 이득을 적절히 조정함으로써 안정된 발진이 이루어짐을 확인하였다. SAW 발진기의 $NO_2$ 가스에 대한 발진주파수의 변이는 28Hz/ppm으로 나타났다.

• 한국전기전자재료학회논문지
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• 제13권4호
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• pp.306-311
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• 2000

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for Li polymer battery. The temperature dependence of conductivity impedance spectroscopy and electrochemical properties of PDF/PAN electrolytes as a function of a mixed ratio were reported for PVDF/PAN based polymer electrolyte films which were prepared by thermal gellification method of preweighed PVDF/PAN plasticizer and Li salt. The conductivity of PVDF/PAN electrolytes was 10$\^$-3/S/cm. 20PVDF5PEN LiCiO$\_$4//PC$\_$10//EC$\_$10/ electrolyte has the better conductivity compared to others. 20PVDF5PANLICIO$\_$4//PC$\_$10//EC$\_$10/ electroylte remains stable up to 5V vs. Li/Li$\^$+/. Steady state current method and ac impedance were used for the determination of transference numbers in PVDF/PAN electrolyte film. The transference number of 20PVDF5PANLiCO$\^$4//PC$\_$10//EC$\_$10/ electrolyte is 0.48.

• 동아시아식생활학회지
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• 제19권6호
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• pp.846-855
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• 2009

This study was performed to assess gender differences in rates of obesity, dietary behaviors, and nutrient intakes among college students living in Gwangju. Anthropometric measurements showed that the body mass indexes (BMIs) of the males and females were $22.1{\pm}2.6$ and $20.1{\pm}2.4$ respectively. All obesity indices including BMI, relative body weight (RBW), % body fat by bioelectrical impedence analysis (BIA), and waist-hip ratio (WHR) were significantly higher in the males than in the females. Abdominal fat was also found to be higher in the males whereas underweight was prominent in the female students. The dietary behaviors of the males as determined by dietary scores, were poorer than those of the females. Twenty-four hour dietary recalls revealed that most nutrient intakes were adequate, exceptions of vitamin C, Ca, and folate intakes in both sexes and Fe intake in the female students. Ca and folate intakes were below 75% of the KDRI for both genders. In addition, Unbalanced energy ratios of carbohydrate, protein, and fat were noted in both genders. Effective nutrition education programs targeting college students should be developed and implemented to increase Ca and folate consumption. It is suggested that gender-based nutrition education approaches be created due to poor dietary behavior in males and inadequate nutrient intakes in female college students.

• Restorative Dentistry and Endodontics
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• 제22권2호
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• pp.809-819
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• 1997

The purpose of this study was to develop an accurate frequency-dependent type apex locator. To compensate the impedence differences of different canal contents, voltage differences were pre-measured and stored for saline, HOsb1/$2O_2$ and NaOCl. The circuit was adjusted to recognize the different voltages of each solution, thereby the machine could automatically compensate the voltage differences. In the process of this study, the following informations were observed. 1. Most stable apical reading was obtained at 500Hz and 10kHz. 2. There were no differences in accuracy among three different frequency types, sign wave, triangular wave and rectangular wave(p>0.05). 3. Before the compensation of voltage differences, saline, H2O2 and NaOCl showed different readings at the apex even with the frequency-type (p<0.05). 4. After compensating the voltage difference, the accuracy was enhanced from + 0.42 to +0.32 in H2O2(p<0.05), from -0.34 to -0.12 in NaOCl(p<0.05).

• 한국전자파학회논문지
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• 제9권5호
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• pp.614-620
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• 1998

본 논문에서는 타원형 커루게이트 도파관의 전파 및 복사특성을 이론적으로 해석한다. 타원형 원통 좌표계에서의 파동방정식의 해는 제1종 및 제2종의 Mathieu함수들로 얻어진다. 타원형 커루게이트 도파관의 전계와 자계들은 반경방향과 각 방향의 Mathieu함수들의 곱의 급수로 나타낼 수 있다. 슬랏 영역과 안쪽 영역의 경계면에서 임피던스 매칭 방법을 사용하여 특성 방정식을 얻는다. 타원형 커루게이트도파관에서의 주모드인 $HE_{11}$모드에 대한 특성방정식을 풀어 어퍼춰에서의 전자계를 계산하고, 또 계의 등가원리(field equivalence principle)를 이용하여 타원형 커루게이트 도파관에서의 복사패턴을 계산한다.

• 한방재활의학과학회지
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• 제21권4호
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• pp.167-179
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• 2011

Objectives: In this study, we used with visceral fat area(VFA)/subcutaneous fat area(SFA) ratio(V/S ratio) and bioelectrical impedence analysis(BIA) for a comparative study between VFA measured from several abdominal computed tomography(CT) images and obesity indexes, such as body mass index(BM), waist circumference(WC), and waist-hip ratio(WHR). Methods: A group of 63 test subjects were gathered in the oriental medical hospital of Kyung-Won university. BIA for body composition and body size for obesity indexes were estimated to evaluate the obesity indexes. Pearson correlation coefficients and regression analysis were used to select useful obesity index. Results: The VFA-CT was significantly related to BMI, SFA, WC, hip circumference(HC), body fat mass(BFM), basal metabolic rate(BMR), and VFA-BIA. Especially, we found that the VFA-BIA and BMI were significantly correlated to VFA-CT. Conclusions: VFA-BIA index is an optimized index for diagnosis and evaluation of obesity. Finally, we found that the BMI is optimized to represent VFA.

• 한방비만학회지
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• 제1권1호
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• pp.21-32
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• 2001

Objectives: The aim of this study was to the effect of very low calorie diet with Chegameuiintang to treat obese patients . Methods: We have evaluated 54 obese patients during very low calorie diet with Chegameuiintang weight-reducing regime by determining the body composition before and 1 month, 2 months after treatment by Bioelectrical impedence analysis . Results: In the change of body composition by the treatment, mean weight reduction was 11.59kg(15.57% of initial weight), mean weight reduction after 1month was 7.68kg( 10.31% of initial weight), mean weight reduction after 2 months was 3.91 kg(5.86% of weight after 1 month). Mean reduction in total fat mass was 8.03kg(2914% of the initial fat mass) which constitutes 69.28%. Mean reduction in lean body mass was 3.56kg(7.59%) Conclusions: This study has demonstrated that the compound therapy of very low calorie diet and Chegameuiintang (Tiganyiyiren-tang) is the good way of weight reduction, which reduces total fat mass and preserves lean body mass.