• 한국진공학회지
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• 제19권1호
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• pp.1-9
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• 2010

진공게이지의 비교교정 방법으로 교정이 가능하고-비교교정은, 2차표준기라고 부르는 교정되어진 게이지와 교정할 다른 게이지의 지시값을 읽어 비교는 방법- 다른 진공관련 실험을 할 수 있는 기체 유량 시스템을 개발하였다. 교정시스템에의 진공용기는 터보분자펌프(TMP)에 의해서 배기하고, 후면에 스크롤펌프를 배치하여 배기시스템을 꾸몄다. 터보분자펌프의 최대허용가능 압력은 펌프의 주입구에서 0.1 Pa까지이며, 이보다 압력이 높아지면 배기속도가 감소하며 압력대 이하의 환경을 조절하기가 매우 어렵게 된다. 현재 133 Pa까지의 높은 압력을 발생시킬 수 있는 새롭게 개발된 기체유량조절시스템은 바이패스 라인에 맞도록 설계된 컨덕턴스-리듀서를 설치하여 터보분자펌프를 안전하게 운용할 수 있도록 하였다. 추가로 진공용기안에 전체압력 범위(0.1 Pa ~ 133 Pa)의 압력을 생성하며 기체 주입과 압력구배를 연구하였다. 압력의 최대 편차는 용기의 위쪽 방향에 위치한 가스 주입구에서 가까운 위치 C에서 1.6%로 나타났다.

• 한국식품저장유통학회지
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• 제18권5호
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• pp.746-754
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• 2011

배합사료를 공급한 양식 넙치와 생사료를 공급한 양식넙치의 핵산 관련 물질 및 유리아미노산 측정을 통한 품질의 차이를 비교하였다. 넙치 등근육의 핵산관련물질은 모든 실험사료구에서 공통적으로 AMP 함량이 가장 높았고 그 다음으로 IMP의 함량이 높았다. 공급한 사료에 따라서 HxR의 성분에는 유의적인 차이(p<0.05)를 보였으나, 핵산 관련물질 조성의 분포양상은 비슷한 경향을 나타내었다. 또한, 넙치 지느러미살의 핵산 관련 물질 조성 중 공급한 사료의 종류에 상관없이 IMP 함량이 공통적으로 가장 높게 나타났으나 함량에는 유의적인 차이를 보이지 않았다. 한편, 어육의 초기 변화 정도를 측정하는 K value는 넙치 등근육에서 MP, CEP 및 FEP의 공급구가 각각 9.63%, 9.83% 및 5.84%를 나타내었고, 넙치 지느러미 살에서는 각각 15.71%, 11.22% 및 17.60%를 나타내었다. 넙치를 사육하는 동안 공급하는 사료의 종류에 따라 등 근육 및 지느러미살의 특정 유리아미노산 함량에는 유의적인 차이가 있으나, 전반전인 유리아미노산의 조성에는 큰 차이가 없었다. 유리아미노산 중에서 taurine 함량이 모든 실험사료구에서 공통적으로 가장 높았고, CEP 및 FEP 공급구는 asparagine과 citrulline의 함량이 MP 공급구보다 높았다. 이처럼, 넙치를 사육하는 동안 공급하는 사료의 종류에 따라 등근육 및 지느러미살의 특정 유리아미노산의 함량에 차이가 나는 것으로 볼 때, 맛과 풍미에 큰 영향을 미치는 유리아미노산 조성의 규명은 기호도를 예측할 수 있는 효과적인 방법이라 생각된다.

• 한국식품영양학회지
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• 제29권3호
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• pp.392-403
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• 2016

The purpose of this study was to investigate the relations between HbA1c level and health risk factor. For analysis, 330 elderly women aged 65 years and over were recruited in Jeonla province, Korea. The subjects were classified into two groups according to their HbA1c level; the diabetic group (HbA1c level${\geq}6.5%$, n=68, 20.6%) and control group (HbA1c level<6.5%, n=262, 79.4%). Demographic characteristics were collected, as well as information on physical measurements, blood tests for biochemical indicators, a health status and health-related life style, dietary behavior, favorite food groups, consumption frequency of food groups and nutrient intake. Educational level of the diabetic group was significantly lower than that of the control group. The height of the diabetic group was shorter, and percentage fat of the diabetic group was higher than those of the control group. In the diabetic group, the higher concentrations of creatinine and activity of alkaline phosphatase were found to be significantly unfavorable factors. Therefore, the diabetic group was assumed to be at risk of decreased liver and renal function. The self-rated health level of the diabetic group has a declining tendency, while the medicine intake was significantly higher than that of the control group, but there are no significant differences in visiting frequency of hospital and community health center. The distribution of physical activity showed a significant difference between the groups. Although there are no significant differences in nutrient intake, the diabetic group had relatively inferior nutrient intake of diet, especially vitamin C, as contrasted with the control group. In conclusion, the weight control and increasing physical activity may be effective in the prevention of the diabetes and continuous education and intervention by specialized nutritionists will be needed for diabetic patients. These results could be useful to plan effective strategies to increase the health-life expectancy and the prevention of the diabetes of Korean elderly people living in rural areas.

• 항공우주시스템공학회지
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• 제13권6호
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• pp.52-59
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• 2019

로터 블레이드는 허브를 통해 전달된 토크와 조종장치를 이용한 피치각 제어를 통해 헬리콥터 비행에 필요한 양력, 추력 및 기동력을 발생시킬 수 있는 핵심 구성품이며, 구조적인 안전성과 함께 공진의 위험성이 없도록 진동 특성을 고려하여 설계되어야 한다. 본 연구에서는 다목적 무인 헬리콥터(Multi-Purpose Utility Helicopter)에 적용하기 위한 주로터 블레이드의 구조 설계를 수행하였으며, 제작된 블레이드의 단면 강성 측정 시험을 수행하였다. 이후 측정된 강성 분포를 반영하여 로터 시스템의 진동특성에 대한 평가를 수행하였다. 로터 블레이드 내부는 스킨, 스파 및 토션박스로 구성되며, 탄소 및 유리 섬유 복합소재를 적용하였다. 블레이드 단면 강성 예측을 위해 Ksec2D 프로그램을 활용하였으며, 실험을 통해 측정된 값과 비교한 결과를 제시하였다. 로터 시스템의 회전으로 인한 고유진동수 변화 및 공진 위험 여부를 확인하기 위해 회전익 항공기의 통합 해석 프로그램인 CAMRADII를 활용하였다.

• 대한지리학회지
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• 제32권4호
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• pp.575-584
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• 1997

지역개발론은 지리학의 중요한 부문을 점유하고 있다. 한국은 지난 30년 동안 일관된 지역개발방향은 중앙의 성장을 억제하고 지방을 육성하는 정책이었다. 그러나 지방과 중앙간의 격차가 해소되지 않고 더욱 커지고 있고, 국가전체가 인적${\cdot}$물적자원을 효율적으로 이용하지 못하여 고비용 저효율은 국가경쟁력의 문제로 제기되고 있다. 중앙집중의 문제는 서울에 인구의 집중에 있고, 인구집중의 원인은 교육의 서울집중에 있다. 따라서 교육의 지방분산이 인구의 지방분산을 초래할 수가 있다. 교육의 지방분산은 인재지역할당제의 법제화로 가능정책 대안이다. 인재 지역할당제는 국가고시(사법고시, 군법무관시험, 행정고시, 기술고시, 외무고시, 입법고시 등)와 주요자격시험(회계사시험, 변리사시험)을 지방의 인구비례로 지방대학에 할당하는 제도이다. 인재지역할당제는 '98년 1월 임시국회에서 입법화가 논의 될 것이다.

• 대한의생명과학회지
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• 제17권4호
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• pp.347-353
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• 2011

The definite mechanism in the control of triglyceride metabolism is not well understood. Nowadays, it has been known that the polymorphism of apolipoprotein C-III $Sst$ I was an important candidate for contributing to the control of triglyceride metabolism. In 298 Korean women aged 30 years or more, the genotypes of apolipoprotein C-III $Sst$ I were statistically compared with total blood cholesterol, triglyceride, high density lipoprotein, fasting blood sugar and hemoglobin A1c. Multiple logistic regression analysis was carried out to compare the odd-ratios of hypertriglyceridemia, hypercholesterolemia and diabetes mellitus with them. The differences among the polymorphic types ($S_1S_1$, $S_1S_2$, and $S_2S_2$) were not statistically significant in the distribution of triglyceride, total cholesterol, high density lipoprotein, fasting blood sugar, and hemoglobin A1c. There were not statistically significant in the odds ratios of the hypertriglyceridemia, hypercholesterolemia, and diabetes mellitus, neither. Those were not statistically significant. This study did not show that there was any association between the polymorphism of apolipoprotein C-III $Sst$ I and various laboratory values-total blood cholesterol, triglyceride, high density lipoprotein, fasting blood sugar and hemoglobin A1c.

• Wind and Structures
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• 제26권5호
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• pp.331-341
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• 2018

A numerical study on the flow over a square cylinder in the vicinity of a wall is conducted for different Couette-Poiseuille-based non-uniform flow with the non-dimensional pressure gradient P varying from 0 to 5. The non-dimensional gap ratio L (=$H^{\ast}/a^{\ast}$) is changed from 0.1 to 2, where $H^{\ast}$ is gap height between the cylinder and wall, and $a^{\ast}$ is the cylinder width. The governing equations are solved numerically through finite volume method based on SIMPLE algorithm on a staggered grid system. Both P and L have a substantial influence on the flow structure, time-mean drag coefficient ${\bar{C}}_D$, fluctuating (rms) lift coefficient ($C_L{^{\prime}}$), and Strouhal number St. The changes in P and L leads to four distinct flow regimes (I, II, III and IV). Following the flow structure change, the ${\bar{C}}_D$, $C_L{^{\prime}}$, and St all vary greatly with the change in L and/or P. The ${\bar{C}}_D$ and $C_L{^{\prime}}$ both grow with increasing P and/or L. The St increases with P for a given L, being less sensitive to L for a smaller P (< 2) and more sensitive to L for a larger P (> 2). A strong relationship is observed between the flow regimes and the values of ${\bar{C}}_D$, $C_L{^{\prime}}$ and St. An increase in P affects the pressure distribution more on the top surface than on bottom surface while an increase in L does the opposite.

• 여성건강간호학회지
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• 제5권3호
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• pp.362-378
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• 1999

This study is to investigate sex role identity and health behavior among university students in Seoul, during the late of 1999. The instruments for data obtainment were KSRI of Kim(1994), and Health Style : A Self-Test provided by ODPHP National Health Information Center. These instrument were reliable, showing Cronbach $\alpha$ .98 and .77. Frequency, t-test, $x^2$-test, stepwise regression were conducted for data analysis, using SAS 6.12 program. The major findings were as follows : 1. For female student. Androgeny(34.0%)type was most common and subjects of feminity type were 28.7%. In contrast, Masculinity type(41.8%) was most prevalent. and undifferentiated type was 30.1% among male students. There were significant difference between male and female student in the type of sex role identity. 2. 89.6% of all subjects were included in risk group for exercise and physical activity, 86.4% for diet habit, 43.2% for alcohol drinking and drug use, 35.6% for stress control, 32.8% for safety behavior, 24.8% for smoking. The big health risk behavior problem of male students were smoking, drinking, diet habit, and exercise. The important health risk behavior problem were diet habit and exercise. There were significant difference in smoking, drinking, exercise between sex. 3. Analysis of the distribution by sex role identity type and health behavior revealed that subjects who were undifferentiated typed group had high risk behavior in stress control, safety, exercise, drinking. Smoking and drinking were more problematic for masculinity typed group had high risk behavior in diet and exercise. The data showed that androginy typed group had more healthy behavior, compared with other sex role identity typed group for all of health behavior. Further research is need to understand the role of sex role identity in health behavior, the variables associated with them. And sex role identity has to be considered in research and practice about health promotion.

• Journal of Power Electronics
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• 제18권2호
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• pp.482-491
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• 2018

The practical design methodology of a three-phase dual active bridge (3ph-DAB) converter applied to low voltage direct current (LVDC) applications is proposed by using a mathematical model based on the steady-state operation. An analysis of the small-signal model (SSM) is important for the design of a proper controller to improve the stability and dynamics of the converter. The proposed lead-lag controller for the 3ph-DAB converter is designed with a simplified SSM analysis including an equivalent series resistor (ESR) for the output capacitor. The proposed controller can compensate the effects of the ESR zero of the output capacitor in the control-to-output voltage transfer function that can cause high-frequency noises. In addition, the performance of the power converter can be improved by using a controller designed by a SSM analysis without additional cost. The accuracy of the simplified SSM including the ESR zero of the output capacitor is verified by simulation software (PSIM). The design methodology of the 3ph-DAB converter and the performance of the proposed controller are verified by experimental results obtained with a 5-kW prototype 3ph-DAB converter.

• 제어로봇시스템학회논문지
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• 제22권5호
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• pp.382-388
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• 2016

When Flat Panel Display (FPD) is made with backlight module, such as LED TV, it inherently suffers from the non-uniform backlight luminance problem that results in un-even brightness distribution throughout the TV screen. If the luminance of each pixel location of a TV screen as a function of the driving voltage can be measured, it can be used to compensate the non-uniformity of the backlight module. We use a carefully calibrated imaging system to take pictures of a TV screen at different levels of brightness and generate the compensation functions for the driving circuitry to correct the luminance level at each pixel location. Making use of the fact that the luminance of the screen is normally brightest at around the center of the screen and gradually decreases toward the border of the screen, the luminance of the whole TV screen is approximated by a mathematical function of the pixel locations. The parameters of the function are computed in the least square sense by the values of both the pixel luminance sent from the driving circuit and the grayscale value measured from the image taken by the imaging system. To justify the correction system, a simple second order polynomial function is used to approximate the luminance across the screen. When the driving circuit voltage is corrected according to the measured function, the variance of the screen luminance is reduced to one tenth of the one measured from the un-corrected TV screen.