• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.16-21
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• 2005

The performance of reciprocating internal combustion engine is a strong function of the air intake system configuration. In order to improve engine power, it is essential to optimize the air induction system. In this study, a numerical investigation has been carried out for the three-dimensional flow and pressure characteristics in air intake system of a large-sized commercial bus. CFD simulations using STAR-CD were also perform ed to evaluate effects of intake duct geometry and structure variation inside air cleaner on the negative pressure distribution of overall intake system. Studies for improving the back pressure distribution have been proposed and quantitatively examined based on intensive case studies.

• Nutrition Research and Practice
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• v.5 no.6
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• pp.548-552
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• 2011

The purpose of this study was to estimate the daily manganese (Mn) intake of Korean children. This study was done using a three-day dietary intake survey of 257 Korean children (boys 123; girls 134). The Mn intake values were calculated based on a database that provides the Mn content of the frequently consumed Korean foods, alongside the food composition table provided by the Korean National Rural Living Science Institute. The average age, height, weight and body mass index of our subjects were 11.9 years, 155.4 cm, 48.9 kg and 20.2 kg/$m^2$ in boys and 11.9 years, 154.1 cm, 43.5 kg and 18.3 kg/$m^2$ in girls. The average daily energy intakes were 2,249.2 kcal in boys and 2,044.5 kcal in girls. Boys consumed significantly more Mn than girls, based on intake estimates of $4,585.3{\mu}g$ (117.6% of adequate intake) and $4,029.3{\mu}g$ (117.1% of adequate intake), respectively (P < 0.001). Boys had a Mn intake of $2,041.1{\mu}g$ per 1,000 kcal of energy consumption, whereas for girls this was at $1,983.9{\mu}g$ per 1,000 kcal. Neither group exceeded the tolerable upper intake level for Mn. The major food groups which contributed to Mn intake in our subjects were cereals (50.8%), vegetables (21.0%), seasonings (8.9%), and pulses (7.7%). Notably, boys derived a higher Mn intake through cereals and vegetable than did girls (P < 0.001, P < 0.05). The key food sources of Mn, in descending order, were rice, soybean curd, kimchi, black rice and cereals. We propose that the results of our study may be used as a basis for follow-up studies that examine the Mn intake of children.

• Journal of Nutrition and Health
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• v.36 no.9
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• pp.950-959
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• 2003

To assess zinc status by dietary intake and urinary excretion of preschool children in Busan and to evaluate the relationship of intakes of food and nutrient with urinary zinc excretion, zinc food frequencies of 40 common foods affecting intakes of zinc by food fequency method, nutrient intake by 24hr recall and 24hr urinary zinc excretion were measured with 97 preschool children. The mean zinc intake was 4.29 mg and 43.0% of RDA. The mean zinc intake per 1,000 kcal was 3.09 mg.97.9％ of subjects had zinc intake less than 75％ of RDA. Grains food group was the primary source of zinc intake and supplied 38.9% of the total daily zinc intake. Altogether, plant food products supplied 49.7% of zinc intake. The mean urinary zinc excretion and zinc excretion per gram of creatinine were 0.19 mg and 1.00 mg respectively. The urinary zinc excretion showed positive significant correlations with height and weight (p < 0.05, p < 0.05) , urine volume and urinary creatinine excretion (p < 0.05, p < 0.001) , urinary zinc excretion per creatinine (p < 0.001) , urinary zinc excretion per weight (p < 0.001) , intakes of energy and carbohydrate (p < 0.05, p < 0.01) and usual intake of zinc from eggs food group (p < 0.05) . In conclusion, these results show that the zinc intake of preschool children is low and that sources of dietary zinc are mainly plant foods, suggesting low bioavailability. So nutritional education is needed in order to inc-rease usual intake of animal food group. Interpretation of urinary zinc excretion data is complicated by current uncertainty about "normal" zinc level at this age group. Further studies are needed to obtain extensive data on urinary zinc excretion for this age group.age group.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.456-464
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• 2016

The purpose of this study was to compare the quantitative and qualitative assessment of dietary intake between patients with metabolic syndrome (MetS) and healthy subjects and to investigate dietary factors related to MetS. Anthropometric measurements, blood analysis, and dietary intake as assessed by 24-hour recall were conducted in MetS patients (n=15) and healthy subjects (n=25). In order to assess the quantity and quality of dietary intake, daily nutrient intake, nutrient density, nutrient intake to dietary reference intake (DRI), nutrient adequacy ratio (NAR), food intake, dietary diversity score (DDS), and dietary variety score (DVS) were analyzed. The statistical differences between MetS patients and controls were analyzed using the SAS software program. Daily energy intake and food intake were not significantly different between the two groups (2,154.3 kcal vs. 1,872.9 kcal; 1,280.0 g vs. 1,261.6 g). There were also no significant differences in daily nutrient intake, nutrient intake ratio to DRI, NAR, or DVS between the MetS group and the control group. However, daily intake of eggs and milk in MetS patients was significantly lower than in the control group (9.0 g/day vs. 30.3 g/day, p<0.05; 0 g/day vs. 49.7 g/day, p<0.05). These results indicate that low intake of eggs and dairy products may be related to the development of MetS.

• Nutrition Research and Practice
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• v.4 no.5
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• pp.421-427
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• 2010

The purpose of this study was to evaluate the daily vegetable and fruit intake status of Korean adults and to examine the relationship of vegetable and fruit intake with bone metabolism. The vegetable and fruit intake of 542 healthy male and female adults was analyzed. Then, by selecting 51 targets from the subjects, the relation of vegetable and fruit intake with serum calcium, osteocalcin and deoxypyridinoline (DPD) excretion in urine was examined. The total vegetable intake per day was 397.7 g and 333.5 g by men and women respectively for the age group of 20-29, 366.9 g and 309.2 g respectively for the age group of 30-49, 378.4 g and 325.9 g respectively for the age group of 50-64. Of vegetable varieties, leafy and stem vegetables displayed the highest intake. The order of major intake items of vegetables and fruits was found to be Chinese cabbage kimchi, onion, radish, cucumber, and welsh onion for the age group of 20-29, watermelon, Chinese cabbage kimchi, peach, potato, and onion for the age group of 30-49 and watermelon, Chinese cabbage kimchi, tomato, potato, and peach for the age group of 50-64. Of 51 targets, ${\beta}$-carotene intake displayed a significantly negative correlation with serum osteocalcin. While caloric intake as well as protein, carbohydrate, calcium, phosphorous, zinc and total food intake displayed a significantly negative correlation with DPD excretion in urine, tuber vegetable intake displayed a significantly positive correlation with DPD excretion in urine. In the future, a study will be necessary to accurately explain the relevance of vegetable and fruit intake with bone mineral density and bone metabolism. Also, efforts will be required to increase vegetable and fruit intake.

• Korean Journal of Community Nutrition
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• v.22 no.1
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• pp.1-12
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• 2017

Objectives: The present study aimed to investigate high school students' sugar intake behaviors, the status of consuming sugary processed foods, the awareness of sugar, and the experience and interest in sugar-related education based on the level of sugar-related nutrition knowledge. Methods: In this study, five high schools were selected in Seoul, Korea, and a survey was conducted in 400 students on the level of sugar-related nutrition knowledge and sugar intake status. A total of 349 questionnaires were used for the final analysis. For statistical analysis, descriptive statistics was performed; a t-test, ${\chi}^2$ test, and Friedman test were used for comparative analysis. Results: The study results showed a positive association between the knowledge level of sugar and the appropriate sugar intake behavior and sugary food choices. The group with more nutrition knowledge on sugar was found to have good eating habits and to eat less sugary food. The main sources of sugar were beverages, confectionary, and bakery goods in the corresponding order, irrespective of the level of nutrition knowledge related to sugar. A significant difference was found in the groups' awareness of the sugar content of the drinks with 89.4% for the higher-knowledge group, and only 81.5% for the lower-knowledge group (p < 0.05). Results also showed that 43.9% of the higher-knowledge group and 36.4% of the lower knowledge group were interested in participating in education on sugar. Conclusions: This study result indicated the need to help adolescents to avoid excessive sugar intake from only certain favorite foods. Therefore, it is necessary to seek a systematic foundation for participatory education in order for them to maintain a low sugar intake in daily life and lead healthy eating habits by increasing their level of sugar-related information and knowledge.

• Journal of Korean Biological Nursing Science
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• v.17 no.4
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• pp.363-371
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• 2015

Purpose: The purpose of this study was to assess alcohol and caffeine intake and identify the impact of alcohol and caffeine intake on body mass index, alcohol use disorder, and quality of sleep among university students. Methods: This study design was accomplished with a cross sectional survey and conducted from May to June 2014. One hundred and twenty-four freshmen of E university in S city, Korea were selected and evaluated by self-administered questionnaires. Alcohol and caffeine intake were measured by self-reported recall. The data were analyzed using descriptive analysis, independent t-test, one-way ANOVA, Pearson's correlation, and multiple linear regression. Results: The average amount of alcohol intake was $175.02{\pm}219.97g$ and the proportion of freshmen who took in more than 40 g per day of alcohol was 75%. The average amount of caffeine intake was $116.79{\pm}111.14mg$. Factors influencing alcohol use disorder were dwelling type (t=2.25, p=.027) and alcohol intake (t=8.11, p<.001). And, the factor influencing quality of sleep was caffeine intake (t=3.88, p<.001). Conclusion: In order to reduce the harmful drinking of university students, preventive activities for freshmen are required and efforts on the part of the school needed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.780-783
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• 2004

Recently Intake noise has been extensively studied to reduce the engine noise. In order to diminish intake noise several resonators were added to the intake system. However this can cause a reduction of engine output power and an increase of fuel consumption. In this study, active noise control simulation of the Filtered-x LMS algorithm is applied real instrumentation intake noise data under rapid acceleration because intake noise is more excessively increased under the such a harsh condition. But the FXLMS algorithm has poor control performance when the system is disturbed. Thus modified FXLMS algorithm using L-point running average filter is developed to improve the control performance under the rapid acceleration and disturbance. The noise reduction quantity of modified Filtered-x LMS algorithm is more than original one in two cases. In the case of control for real instrumentation intake noise data, maximum residual noise of modified FXLMS algorithm is 2.5 times less than applied the FXLMS and also in the case of disturbed, the modified FXLMS algorithm shows excellent control performance but FXLMS algorithm cat not control.

• Journal of Nutrition and Health
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• v.32 no.1
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• pp.75-82
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• 1999

In order to investigate the longitudinal changes on zinc secretion of lactating women and zinc intake of breast-fed infants, we examined 20 lactating women(10 primipare and 10 multipare) and their infants during the first 90 days postpartum. We measured the consumed volume of human milk by test-weighing method and zinc concentration by atomic absorption spectophotometry after wet digestion. Weight gain of infants was -5.7, 54.1, 46.3, 42.0 and 32.3g/day at 7, 15, 30, 60 and 90 days postpartum, respectively. The secretion volume of human milk was 527, 608, 724, 841 and 798g/day respectively. The consumed volume of human milk of breast-fed infants was 432, 503, 603, 715 and 715g/day. The intake level of breast milk to secretion volume reached 85.0% in average. The zinc concentration of the milk was 4.29, 3.32, 2.52, 1.62 and 1.18mg/l, and the zinc intake of breast-fed infants was 1.80, 1.69, 1.45, 1.15 and 0.70mg/day. Zine intake per body weight of infants averaged 0.32mg/kg/day during the first 90 days postpartum. The average zinc intake of breast-fed infants was 1.36mg/day, which is 27.2% of the recommended daily allowance for 0-4-month-old infants.

• Nutrition Research and Practice
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• v.4 no.5
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• pp.433-437
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• 2010

In order to develop an obesity management program for teenagers, we compared obese and non-obese girls attending high schools in terms of their dietary practices related to snack consumption. Dietary records were collected for 7 days. No significant differences were found for the average daily energy intake between obese and non-obese girls. However, the highest energy intake was greater for obese girls while not much difference was found for the lowest amount of energy intake. Obese girls had significantly lower intakes in calcium (P < 0.01), vitamin A (P < 0.001) and folate (P < 0.01). Mean energy intake from snack ($594.1{\pm}312.1kcal$) was significantly higher for obese girls than for non-obese girls ($360.1{\pm}173.1kcal$) (P < 0.001). A significant, positive correlation was observed between energy intake from snack and total daily energy intake (r = 0.34 P < 0.01) only for obese girls. In case of dietary behaviors, obese adolescent girls consumed significantly greater number of items for snacks and fewer foods for regular meals compared to non-obese girls (P < 0.05). This study suggested that obesity management programs for adolescents should focus on providing strategies to reduce snack through enhancing balanced regular meals.