• 동아시아식생활학회지
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• 제22권4호
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• pp.452-462
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• 2012

The study was conducted to investigate the dietary behaviors and lifestyles of Korean university students and Chinese international students in the Jeonbuk area. Self-administered questionnaires were collected from 241 Korean university students and 198 Chinese international students. Statistical data analysis was completed using SPSS v. 12.0. Breakfast-skipping among subjects was very common, and the most frequently given reason for skipping this meal was 'lack of time'. More than 85% of Korean male students and 75% of Korean female students reported regularly eating lunch in university canteens or restaurants around campus, whereas 86% of Chinese male students and 82% of Chinese female students regularly ate their lunches in university canteens or at home. About 62% of Korean male students, 72% of Korean female students, 48% of Chinese male students, and 70% of Chinese female students responded that they do not regularly eat dinner, the main reasons cited for this being 'irregularity of lifestyle' and 'part-time work'. Snack intake by the subjects was high. Beverages were the snack item most frequently consumed by Korean and Chinese male students, whereas cookies and fruits were most frequently consumed by Korean and Chinese female students. About 28% of Korean male students and 44% of Chinese male students were smokers, respectively. Half of Chinese female students drank alcohol once or twice a week. About 42% of Korean male students and 65% of Chinese male students played sports, respectively. Dietary behaviors and lifestyles of Korean and Chinese students tended to be very similar. Chinese students performed more health-oriented activities in comparison to Korean students. In conclusion, a practical and foreigner-friendly nutritional education program should be devised in order to correct the dietary behaviors and health-related lifestyles of Korean and Chinese students.

• 공학논문집
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• 제2권1호
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• pp.125-131
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• 1997

유리용해로의 축열실은 폐연소가스로 열을저장하며, 유리용해로에 유입되는 흡입공기를 예열시키는 역할을 한다. 유리용해산업에서 연료소비를 줄이기 위하여 절연법, 단열벽돌, 공기누출등이 오래 연구되었다. 또한 새로운 형태의 단열벽돌과 Rider arch가 유리용해로의 수명연장을 위하여 연구되고 있다. 본 연구는 연구대상공장의 이전설치시 유리용해로의 축열실이 5.64m에서 7.89m로 높이가 높아졌고 이에 따른 축열실 하중증가에 의하여 Rider arch가 더 높은 응력을 받게 되었다. 이런 조건에서 Rider arch의 기계적 안정성을 본 연구에서 검토하였다. 계산식에 의하면 하중증가에 따른 Rider arch의 응력은 안정한 것으로 평가되었고 Rider arch가 견딜수 있는 최대 압축응력은 163kg/$cm^2$이고, 최대전단응력은 6.37kg/$cm^2$이다.

• Preventive Nutrition and Food Science
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• 제16권3호
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• pp.217-223
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• 2011

Ischemic stroke constitutes about 80% of all stroke incidences. It is characterized by brain cell death in a region where cerebral arteries supplying blood are occluded. Under these ischemic conditions, apoptosis is responsible for the cell death, at least in part. Goat's-beard (Aruncus dioicus var. kamtschaticus) is a perennial plant that grows naturally in the alpine regions of Korea. In the present study, we first determined whether water extract of goat's-beard (HY1646) and some of its fractions prepared by partitioning with organic solvents could improve the viability of human hepatocellular carcinoma cells (HepG2) cultured under hypoxic condition by blocking apoptotic pathways. Based on the in vitro findings, we subsequently investigated whether HY1646 and the ethyl acetate fraction (EA) selected from cell culture-based screening could attenuate brain injury in a rat middle cerebral artery occlusion (MCAO) model of ischemia (2 hr), followed by 22 hours of reperfusion. The cell number was sustained close to that initially plated in the presence of HY1646 even after 24 hr of cell culture under hypoxic condition (3% $O_2$), at which time the cell number reached almost zero in the absence of HY1646. This improvement in cell viability was attributed to the delay in apoptosis, identified by the formation of DNA ladder in gel electrophoresis. Of fractions soluble in hexane, ethyl acetate (EA) and butanol, EA was chosen for the animal experiments because EA demonstrated the best cell viability at the lowest concentration (10 ${\mu}g$/mL). HY1646 (200 mg/kg) and EA (10 and 20 mg/kg) significantly reduced infarct size, an index of brain injury, by 16.6, 40.0 and 61.0%, respectively, as assessed by 2,3,5-triphenyl tetrazolium chloride staining. The findings suggest that prophylactic intake of goat's beard might be beneficial for preventing ischemic stroke.

• 대한화학회지
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• 제8권3호
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• pp.93-97
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• 1964

금반 한국여자대학생 28명에 대하여 소비열량과 영양상황을 조사한 결과를 요약하면 다음과 같다. 1) 본조사에 있어서 여자대학생(20-21세)의 평균신장은 157.1cm, 체중 51.75kg, 체표면적 1.5m$^2$, 기초 대사량 1303Cal, 안정시 대사량 1563Cal, 활동대사량 469Cal, 1인 1일 총평균 소비열량(요구열량) 2032Cal였다. 한편 그들의 섭취열량은 1880Cal 로서 152Cal가 소비열량보다 부족하게 섭취되어져 있었다. 2) 단백질, 철분, 비타민B1, C는 요규량에 족하였고, Calorie, 지방, 탄수화물, 칼슘, 비타민 A, B2 는 섭취량이 부족하였다. 3) 총 54종의 식품에 의하여 먹혀졌으며 주로 식물성식품(83.7%)에 의하여 영양이 공급되었고 동물성식품은 16.2%밖에 공급되지 않았었다. 또한 수산동식물성 식품은 불과 7.4% 밖에 영양을 주지 못한 식성구성을 이루고 있었다.

• 치위생과학회지
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• 제20권1호
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• pp.44-50
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• 2020

Background: Smartphones are a modern necessity. While they are convenient to use, smartphones also have side effects such as addiction. This study assessed the relationship between smartphone use, a part of everyday life in modern society, and oral health. Methods: An analysis was conducted using 2017 Korea Youth Risk Behavior Web-based Survey data. The propensity score estimation algorithm used logistic regression and 1:1 matching algorithm using nearest-neighbor matching. After matching, a total of 15,032 participants were classified into two groups containing 7,516 teenagers each who did and did not use smartphones, respectively. Results: Comparison of oral health behaviors according to smartphone use revealed a statistically significant difference in the frequency of tooth brushing per day, use of oral hygiene products, intake of foods harmful to oral health, and experience of oral health education (p<0.05). The factors affecting oral pain experience of adolescents were examined. Compared to male participants, female participants had an odds ratio of 1.627 for oral pain (p<0.05). According to the household income level, compared to the group with higher income, the group with lower income showed higher oral pain experience (p<0.05). Oral pain experience was 1.601 times more frequent among teenagers using smartphones (p<0.05). Conclusion: The results of this study indicated that use of smartphones by adolescents affected their oral health. These findings indicate the need for improved oral health management through the use of effective school oral health programs and individual counseling by oral health professionals, promotion of information dissemination through public media, and development of prevention strategies.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.848-853
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• 2004

Regarding to the project SUAV (Smart Unmanned Aerial Vehicle) in KARI (Korea Aerospace Research Institute), several engine configurations has been evaluated. However it's not an easy task to collect all the necessary data of each engine for the analysis. Usually, some kind of modeling technique is required in order to determine the unknown data. In the present paper a qualitative method for reverse engineering is proposed, in order to identify some design patterns and relationships between parameters. The method can be used to estimate several parameters that usually are not provided by the manufacturer. The method consists of modeling an existing engine and through a simulation, compare its transient behavior with its operating envelope. In the simulation several parameters such as thermodynamics, performance, safety and mechanics concerning to the definition of operation-envelope, have been discussed qualitatively. With the model, all engine parameters can be estimated with acceptable accuracy, making possible the study of dependencies among different parameters such as power-turbine total inertia, TIT, take-off time and part load, in order to check if the engine transient performance is within the design criteria. For more realistic approach and more detailed design requirements, it will be necessary to enhance the compressor map first, and more realistic estimated values must be taken into account for intake-loss, bleed-air and auxiliary power extraction. The relative importance of these “unknown” parameters must be evaluated using sensitivity analysis in the future evaluation. Moreover, fluid dynamics, thermal analysis and stress analysis necessary for the resulting life assessment of en engine, will not be addressed here but in a future paper. With the methodology presented in the paper was possible to infer the relationships between operation-envelope and engine parameters.

• 대한지역사회영양학회지
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• 제24권5호
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• pp.422-432
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• 2019

Objectives: The purposes of the study were to assess wastes generated in school foodservice and to identify factors influencing the generation of plate waste. Methods: A survey was administered from November 18-30 in 2015 to dietitians and nutrition teachers that were employed in schools located in Gyeonggi province. A questionnaire file and on-line survey site link were sent to the dietitians and nutrition teachers by e-mail. A total of 622 dietitians and nutrition teachers responded and 594 responses were used for data analysis after excluding 28 responses with significant missing data. Results: Plate waste was the major part of food waste generated in school foodservice. Vegetable menus and soup/stews were discarded the most as plate waste. The dietitians and nutrition teachers perceived students' unbalanced diet and lack of appreciation of food as causes of the plate waste. Regarding waste management, they were concerned about environmental contamination by food waste and felt uncomfortable about discarding food. No plate waste day was the most frequently used plate waste reduction activity, followed by newsletters on plate waste reduction. Difficulty in getting teachers' support for dietary education during meal time was rated the greatest barrier to implementing the activities. To reduce plate waste, they perceived that students should understand the importance of environment conservation, teachers should supervise students' eating during meal time, students should be educated about proper portion, and foodservice staff should improve food quality. Conclusions: To improve students' intake and reduce plate waste in school foodservice, foodservice staff need to involve students in school foodservice and improve the palatability of meals, especially vegetable dishes. School nutrition teachers and dietitians should educate students about healthy eating and environment conservation and the school community needs to understand and support plate waste reduction and healthy eating in schools.

• Journal of Nutrition and Health
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• 제41권4호
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• pp.341-352
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• 2008

The number of school lunch-supported children who belong to low-income families has been rapidly increased in Korea. This study was aimed at evaluation of nutritional status of school lunch-supported elementary school children. One hundred school lunch-supported children and 119 non-supported children of fourth to sixth year class in 3 elementary schools in Gyeongbuk rural area were selected, and surveys were conducted twice, i.e., once during school term and once during summer vacation in 2006. Food consumption survey during school term was carried out through an interview by dieticians at school-lunch time using a 24-hour recall method, and the survey during summer vacation conducted by recording food intakes for three days by children. Nutrient intakes were calculated using CAN-Pro 3.0 program. School lunch-supported children showed higher rate of skipping breakfast and rather irregular meal time as compared to non-supported students. Eating alone was more frequent in school lunch-supported children than in nonsupported children. The average nutrient intakes and nutrient adequacy ratios were lower in supported children than in non-supported children. During term, percentages of nutrient intakes provided by school-lunch were higher in supported children than in non-supported children. Intakes of energy nutrients were within acceptable macronutrient distribution ranges, but proportion of carbohydrate intake increased during vacation. Analysis of patterns of food intakes based on major food groups (dairy, meat, grain, fruit, vegetable) indicated that meals during term were more balanced as compared to meals during vacation. In conclusion, food behaviors and nutrient intakes of school lunchsupported children were inferior to those of non-supported children during term and during summer vacation. They were provided with more nutrient intakes from school lunch during term as compared to non-supported children. Therefore, it is necessary not only to keep meal support program during vacation but also to provide a proper nutrition education as a part of school lunch program to improve nutritional status and food behaviors of school lunch-supported children.

• 한국가스학회지
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• 제15권3호
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• pp.47-52
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• 2011

이 논문의 목적은 LPG 자동차의 전자제어에 대한 요소의 하나인 액추에이터에 대한 고장사례를 찾아 분석하고 연구하는 것이다. 차량의 연료를 저장하는 봄 내부의 LPG 긴급 차단 솔레노이드 밸브의 필터가 막혀 연료의 공급이 간헐적으로 차단되는 현상이 발생되어 엔진이 작동하는 동안 엔진의 초기시동불량이나 가속이 되지 않는 것을 확인하였다. 엔진 컨트럴 릴레이 부위의 접점부가 가공불량이나 조립불량에 의해 완전한 면접촉이 되지않아 접촉저항이 발생되어 초기 시동을 걸었을 때 시동이 걸렸으나 재시동을 걸 때 시동이 걸리지 않는 현상을 확인하였다. 공회전 조절장치의 내부에 카본이 퇴적되어 액추에이터가 고착되어 흡입공기의 공급이 감소되어 자동차의 시동이 걸려 공회전 상태일 때 엔진의 회전수가 규정 범위를 벗어나 상승과 하락을 반복하는 불안정 상태를 확인하였다.

• International journal of advanced smart convergence
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• 제8권1호
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• pp.113-125
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• 2019

The radish skin and radish greens are an edible part of the radish. But they are removed before eating the radish and used as a byproduct or an animal feed material because of their tough and rough texture. This study was conducted to investigate the effect of supercritical heat-treated radish-extract on UV-induced HRM-2 wrinkled mouse animal model on anti-aging wrinkles. Supercritical heat-treated radish-extract was applied on the back of seven-weeks old HRM-2 mice. The effect of HRE on skin thickness, elasticity and wrinkle formation of the mice was observed by using UVB lamp to induce melanogenesis and wrinkle formation. As the result, increased depth of wrinkles was observed in the negative control group in comparison to the normal group. In contrast, decreased depth of wrinkles was observed in the radish-extract-free group compared to the negative control group. In the study of the effect of radish-extract on wrinkle-formation related gene expression and protein what protein expression, MMP-2 and MMP-9 gene expression significantly increased in the negative control group compared to the normal group. The gene expression reduced in dependence to the mass of radish-extract treated. Similar to quantitative results of mRNA expression, the expression of MMP-2 protein increased as a result of UVB-irradiation. The MMP-2 expression was inhibited in dependence to the mass of radish-extract treated. In conclusion, the supercritical heat-treated radish-extract has an effect on improving skin wrinkles not only when it is applied to the skin but also when orally ingested. Thus, it can be effectively used as a composition to health functional products. Therefore we can also conclude that radish a food that does not show any side-effects even upon long-term intake can reduce wrinkle formation as well as improve skin elasticity when taken regularly for a long period.