• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.351-354
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• 2005

Research purpose of this project is intending Maintenance Free of freight car and speed up of freight train. At goods transport as heightening traveling by ship speed of freight train shortening raise railway share of physical distribution and stand on tiptoe to Northeast Asia physical distribution main country to contribute expect. This paper is the performance elevation methods of next generation railway freight vehicles.

• 한국구조물진단유지관리공학회 논문집
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• 제12권4호
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• pp.161-167
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• 2008

본 연구에서는 고등해석과 유전자 알고리즘을 이용한 트러스 구조물의 최적설계를 수행하였다. 본 연구에서 사용한 고등해석은 기하학적 비선형과 재료적 비선형을 동시에 고려한다. 최적화 알고리즘으로 마이크로 유전자 알고리즘을 사용하였다. 목적함수로 구조물의 중량을 사용하였으며, 제약조건식은 구조시스템의 하중-저항능력 및 변위 조건을 고려하였다. 제안된 방법에 의한 최적설계 결과를 기존의 연구결과와 비교하여 그 타당성을 증명하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제3권1호
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• pp.121-128
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• 1999

In this study, the behavior of R/C beams strengthened with carbon fiber laminate (CFL) is analyzed from the test results. CFL is attractive for this application due to its good tensile strength and low weight. Test parameters are the width and the thickness of CFL and repair of damaged specimen. The failure mode and ultimate load are analyzed from these measured data. Test results show that the peak load of specimens strengthened with CFL is increased to 1.27~2.04 times that of non-rehabilitation specimen. The wider lap width, larger amount of CFL, the larger strength is obtained. But the ductile behavior of the rehabilitated specimens is inversely proportional to the CFL thickness.

• 한국구조물진단유지관리공학회 논문집
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• 제6권4호
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• pp.99-106
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• 2002

합성데크구조에서 보와 바닥판은 공사중 처짐이 발생한다. 이 렌즈형태의 처짐은 건물의 사용성 문제를 야기시킨다. 따라서, 수평이 되도록 보정되어야 한다. 수평보정을 위한 몇가지 방법이 있는데 (1) 부재의 강성을 증가하거나 (2) 지주로 바닥을 받치거나 (3) 보에 치올림을 두거나 (4) 추가 콘크리트를 타설한다. 본 연구에서는 추가콘크리트를 이용하여 바닥면을 수평보정하는 경우 여러 가지의 바닥크기에 대하여 추가콘크리트의 중량과 체적을 비교 검토하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제6권4호
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• pp.201-207
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• 2002

An advanced fiber sheet has been widely used for strengthening of the concrete structures due to its excellent properties such as high strength and light weight. Bond strength is very important in strengthening the concrete structures using an advanced fiber sheet. This research examines the bond behavior between fiber sheet and concrete, investigates the bond strength by the direct pull-out test and the tensile-shear test. To obtain the tensile-shear strength a double-face shear type bond test is conducted. The primary test variables are the types of concrete surface roughness (disk-grinding/chipping) and retrofitting methods (bonding/injection). Thirty specimens were tested to evaluate the bond strength. It is shown that the average bond strength between fiber sheet and concrete by the direct pull-out test and the tensile-shear test is $22.3{\sim}23.1kgf/cm^2$ $17.92{\sim}19.75kgf/cm^2$, respectively.

• 한국구조물진단유지관리공학회 논문집
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• 제8권1호
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• pp.121-128
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• 2004

본 연구는 폴리머 종류변화에 따른 폴리머 시멘트 콘크리트에 대한 각종 물리적 특성을 통하여 신 건설재료로써의 응용 및 실용화를 위한 기초자료가 되도록 하는데 본 연구의 목적이 있다. 본 실험의 결과를 종합하여 볼 때 폴리머를 이용한 시멘트 콘크리트는 폴리머 종류에 따라 콘크리트의 특성이 다소 차이는 있으나 압축강도, 인장강도, 흡수율, 중량감소율 및 동결융해에 대한 저항성이 우수한 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.335-341
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• 2003

Carcass weight and backfat thickness are two of important elements in determining the carcass trait in pigs and are studied on animal genetics, nutrition, and endocrinology. Growth factors stimulate or inhibit the proliferation and differentiation of various cells. In particular, insulin-like growth factors (IGFs), transforming growth factor (TGF)-$\beta$, and epidermal growth factor (EGF) are involved in the growth and maintenance of muscle. Also, dehydroepiandrosterone-sulfate (DHEA-S) and cortisol are known to be related to the obesity and subcutaneous fat depth in pigs. Therefore, this study was performed to relate growth factors (IGFs, TGF-${\beta}1$, and EGF) and hormones (cortisol and DHEA-S) concentrations at antemortem and postmortem periods to carcass traits including carcass weight and backfat thickness. Blood and m. Longissimus were collected in pigs at antemortem (30 days before slaughter) and postmortem periods. After slaughtered, carcass weight and backfat thickness were measured. Growth factors and hormones in serum and m. Longissimus were measured by radioimmunoassay or enzyme-linked imuunosorbent assay. Before antemortem period, serum IGF-I and -II concentrations were positively correlated with the carcass weight and backfat thickness in gilts, and the concentrations of TGF- ${\beta}1$ and cortisol in barrows show the correlation with only carcass weight. Also, the positive correlations of muscular IGFs and TGF-${\beta}1$ at postmortem 45 min with the carcass weight and backfat thickness were detected. Consequently, these results suggest that the serum and muscular endocrine factors are involved in the carcass weight and backfat thickness in pigs.

• 산업경영시스템학회지
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• 제42권3호
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• pp.252-261
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• 2019

In this study, we analyzed the factors affecting the introduction of Smart Factory by domestic SMEs through AHP analysis and tried to provide implications for the introduction of Smart Factory. It was confirmed that the manufacturing and introduction group, the non-manufacturing introduction group, and the already introduced group had the highest weight in the cost reduction in the first hierarchy standard. At this time, it can be seen that the weight for cost reduction is relatively high in the manufacturing introduction group and the introduction group, and the weight for the productivity improvement is relatively high in the non-manufacturing introduction group. It can also be seen that the portion of marketing enhancement does not have a significant impact on smart factory choices. It was confirmed that image enhancement is the highest in the manufacturing introduction group and the non-manufacturing introduction group in the first hierarchy standard, and the marketing has the highest weight in the introduction group. In the two - tiered standard, customer - friendly and proper inventory maintenance weights were relatively high in all the introduced groups, except for the high rankings.

• 대한지역사회영양학회지
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• 제12권1호
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• pp.80-89
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• 2007

This study was performed to investigate the effectiveness of nutritional education and exercise intervention on reduction and maintenance of weight. The subjects were 24 obese women whose body mass index(BMI) was over $25kg/m^2$. Nutritional education was performed once a week and swimming was done three times a week throughout this 12 week program. The subjects were recalled 1 month after the program was complete. Nutrient intakes were assessed by 24 hour recall method. Also food habits, dietary behaviors and nutritional knowledge were investigated by self-administered questionnaires before and after the weight control program and one month after completing the program. Height, weight, body composition and blood levels were measured before and after the weight control program and one month after completing the program. During the 12 weeks of the weight control program, body weight significantly decreased from an average of 69.7kg to 65.8kg and to 65.1kg after one month(p<0.05). Body fat and BMI also significantly decreased(p<0.01). Cholesterol and blood sugar levels decreased after 12 weeks and increased one month after completing the program. After taking nutritional education, the nutritional knowledge scores increased. Calcium intake significantly increased after completing the education and one month after completing the program(p<0.01). Iron intake significantly decreased from an average of 12.1g to 11.3g after completing the program and increased to 15.5g one month after completing the progrom(p<0.001). We concluded that our nutritional education and exercise program was effective for reducing and maintaining weight.

• Nutrition Research and Practice
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• 제14권2호
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• pp.160-166
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• 2020

BACKGROUND/OBJECTIVES: The obese population is rapidly increasing because of reduced physical activity and a Westernized diet; consequently, various chronic diseases are more prevalent. With the increasing interest in body shape and appearance, research on body shape perceptions and accompanying weight control behaviors are needed for healthy weight management. SUBJECTS/METHODS: A cross-sectional survey was conducted on randomly selected 536 (209 men and 327 women) aged 20 to 65 years. Body mass index (BMI), body-shape perception, weight control behavior, quality of sleep, and place of residence were collected using self-reported questionnaires. Multivariable logistic regression analysis was conducted using complex design in each groups. Collected data were analyzed using the SAS 9.4 statistical package, and the significance level was set at P < 0.05. RESULTS: When these two variables were divided into four groups, they were found to influence dieting attempts. People with abnormal weights who were dissatisfied with their body shapes attempted dieting 5.23 times more than those with healthy weights and satisfaction with their body shapes. Further, those with normal weights but dissatisfaction with their bodies attempted dieting 4.45 times more than those who were satisfied with their shapes. Subjects in their 20s attempted dieting 2.53 times more than those in their 30s and 40s, and female subjects attempted dieting 2.24 times more than male subjects. CONCLUSIONS: A correct perception of one's shape can be an important factor for dietary behavior, as body shape perceptions and dieting attempts are strongly related. Additionally, healthy weight management and nutrition education are important elements to incorporate into a weight control program aimed at preventing excessive weight control behaviors and promoting correct perceptions of body shape.