• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1128-1136
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• 2017

Previous studies of the caffeine consumption pattern were limited primarily to beverages containing caffeine. Therefore, this study examined the caffeine consumption patterns and levels in beverages and foods containing caffeine among high school students (n=310) in the Yongin region. The participants included 171 boys (55.2%) and 139 girls (44.8%). The daily mean caffeine intake of the respondents was 41.27 mg (0.651 mg/kg) and 36.47 mg (0.696 mg/kg) in boys and girls, respectively. Among the caffeinated food groups, coffee had the highest caffeine intake group in both boys (18.95 mg) and girls (26.28 mg). Girls consumed large amounts of caffeine in the form of Americano-style coffee (20.04 mg), whereas boys consumed more canned coffee (6.77 mg) than girls (2.43 mg, P<0.01). Carbonated soft drinks were the second most prevalent source of caffeine intake in both groups, even though boys (14.29 mg) consumed larger amounts of caffeine than girls (5.85 mg, P<0.001). Multiple regression analysis investigating the major contributing food group to daily total caffeine intake also showed that the highest standardized coefficient was in coffee regardless of gender (boys 0.492, P<0.001 and girls 0.944, P<0.001), followed by carbonated soft drinks and energy drinks. Approximately 95% of high school students consumed normal levels of caffeine, whereas 3.5% of boys and 5.8% of girls consumed excessive amounts based on the standard limit of Korea Food and Drug Administration (<2.5 mg/kg/d) for adolescents. The daily mean caffeine intake of the excess group was 5.38 mg/kg and 6.96 mg/kg in boys and girls, respectively. Consequently, safe daily caffeine intake needs to be determined throughout continuous national management guidelines and nutritional education.

• International Journal of Railway
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• v.2 no.3
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• pp.124-126
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• 2009

Energy savings can be achieved with optimum energy consumptions, brake energy regeneration, efficient energy storage (onboard, line side), and primarily with light weight vehicles. Over the last few years, the rolling stock industry has experienced a marked increase in eco-awareness and needs for lower life cycle energy consumption costs. For rolling stock vehicle designers and engineers, weight has always been a critical design parameter. It is often specified directly or indirectly as contractual requirements. These requirements are usually expressed in terms of specified axle load limits, braking deceleration levels and/or demands for optimum energy consumptions. The contractual requirements for lower weights are becoming increasingly more stringent. Light weight vehicles with optimized strength to weight ratios are achievable through proven design processes. The primary driving processes consist of: $\bullet$ material selection to best contribute to the intended functionality and performance $\bullet$ design and design optimization to secure the intended functionality and performance $\bullet$ weight control processes to deliver the intended functionality and performance Aluminium has become the material of choice for modern light weight bodyshells. Steel sub-structures and in particular high strength steels are also used where high strength - high elongation characteristics out way the use of aluminium. With the improved characteristics and responses of composites against tire and smoke, small and large composite materials made components are also found in greater quantities in today's railway vehicles. Full scale hybrid composite rolling stock vehicles are being developed and tested. While an "overdesigned" bodyshell may be deemed as acceptable from a structural point of view, it can, in reality, be a weight saving missed opportunity. The conventional pass/fail structural criteria and existing passenger payload definitions promote conservative designs but they do not necessarily imply optimum lightweight designs. The weight to strength design optimization should be a fundamental design driving factor rather than a feeble post design activity. It should be more than a belated attempt to mitigate against contractual weight penalties. The weight control process must be rigorous, responsible, with achievable goals and above all must be integral to the design process. It should not be a mere tabulation of weights for the sole-purpose of predicting the axle loads and wheel balances compliance. The present paper explores and discusses the topics quoted above with a view to strengthen the recommendations and needs for the weight optimization by design approach as a pro-active design activity for the rolling stock industry at large.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.176-184
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• 2017

The purpose of this study was to evaluate total sugars intake and determine its relationship with nutrient density and obesity degree in elementary school children. A total of 1,292 elementary school students (638 boys, 654 girls) in Chungnam participated in this study. Daily total sugars intake of subjects was analyzed using the USDA database of sugars after a questionnaire survey using 24-hour recalls. The average age of subjects was 9.7 years, daily energy intake was 1,834.0 kcal, and total sugars intake was 37.6 g/day, which was 8.3% of total energy intake. Sugars intake from the milk group was highest at 18.4 g/day, followed by fruits, cereals, sugars and sweeteners, and beverages. Nutrient density of protein as well as Na, Fe, and Zn levels were significantly lower according to total sugars intake level. There was no significant difference between overweight and obesity risk among the sugars intake quartile groups. In conclusion, total sugars intake of subjects was not significantly high and not associated with obesity risk; however, high sugars intake in children was associated with decreased consumption of protein, Fe, and Zn, which are important for growth.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.3
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• pp.101-109
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• 2011

In this paper, we present a new routing protocol, multipath and multi-priority based routing protocol, (MMRP) for wireless multimedia sensor networks. The proposed MMRP chooses the multiple routing paths from source to the sink, then the selected paths are assigned with different priority levels depending upon the residual energy and transmission delay in the routing paths. That is, the highly prioritized I frames of the MPEG video are transmitted over the high priority routing paths, and other P and B frames are transmitted over the lower priority routing paths. The proposed MMRP protocol can be applied to time critical applications which require both lower latency and low power consumption over wireless multimedia sensor network. Simulations results of MMRP protocol show respectively an improvement of 23.48% and 23.11% in energy conservation and 81.6% and 32.01% improvement in latency as compared to protocols without and with multipath routing.

• Journal of Nutrition and Health
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• v.32 no.4
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• pp.407-418
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• 1999

The purpose of this study was to identify dietary factors related to the incidence of diabetes mellitus in Korea. The study consisted of 165 diabetic patients, male and female, aged 30 to 70 years and 198 healthy persons as controls. Diabetic patients who had been diagnosed with diabetes mellitus for less than five years before the study period were recruited from eight different hospitals located in Seoul, Korea. Socioeconomic status, state of illness, physical activity, food habits and food intake were assessed. Food intake was assessed by food frequency questionnaire method using a 105-food frequency questionnaire developed for diabetic patients. The stress and activity indices of diabetic patients were not significantly different from control, but alcohol consumption and smoking levels were higher in diabetics than controls. Other diseases of male diabetic patients included liver diseases, digestive system diseases, and hypertension, while those of female diabetics were hypertension, neuralgia, arthritis and digestive system diseases. These disease patterns are different from Western countries whose most common complications are hypertension and hyperlipidemia. More irregular and less varied meals were found in the diabetic group compared to the control group, suggesting that diabetic patients have generally undesirable food habits. Otherwise, food and nutrient intake of diabetics did not differ greatly from the control group. It was found that diabetic patients consumed more cereals and less fruit than the control group, and also that male diabetics consumed more alcohol. The carbohydrate : protein : fat energy distribution ratio was 61.7 : 15.8 : 22.5 in male patients and 65.1 : 14.9 : 19.7 in female patients. Discriminant analysis showed that diabetes risk factors differed with sex. In male patients, the important factors were body mass index(BMI), vitamin C intake, family diabetic history and vegetable intake, while in female patients they were BMI, cereals intake, carbohydrate intake, vitamin C intake, stress, food habits and Ca intake. These results show that excessive intake of energy and fat are not the major causal factors in Korean NIDDM. Therefore, the diabetes risk factors of Western countries may not directly apply to Koreans. Mors study is needed to clarify the risk factors of Korean NIDDM.

• Journal of Community Nutrition
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• v.2 no.1
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• pp.5-11
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• 2000

Populations both in the US and worldwide are aging. It is projected that by the year 2030 the population of Americans over 65 will increase to 70 million, more than twice their number in 1998. About one-third of elderly over the age of 65 have debilitating chronic health conditions that greatly impede their activities. Age-associated chronic diseases are believed to be associated with free radicals and the imbalance in antioxidant and oxidative stress contributes to development of several chronic health conditions. Diet and nutrients can have great impact in the health status of elderly. Several factors may contributor to the inadequate consumption of nutrients in elderly, including an inability to chew food adequately, polypharmacy, living along and limited income. Low intake of energy and several micronutrients are common among the elderly. Although overt deficiency of nutrients among the elderly is not common. a recent study showed that while elderly consume more fat, the total energy intake is low among the elderly. Inadequate intake of antioxidant nutrients such as vitamin E in elderly may contribute to the development of chronic health problems. Intake of higher than normal RDA levels of vitamin E for long periods of time has been shown to reduce the risk of many degenerative diseases, such as cardiovascular diseases(CVD) and cancer, and improve immune response in elderly. High intake of other antioxidants is also associated with reduced risk chronic diseases. Dietary antioxidants are abundant in fruits and vegetables. However, due to variety of factors, the elderly may not be able to receive these and other micronutrients through diet. Therefore, supplemental intake of micronutrients in the form of multi vitamins/minerals and/or specific micronutrients is a more practical approach to the maintenance of health status in the elderly.

• Korean Journal of Community Nutrition
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• v.28 no.2
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• pp.141-159
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• 2023

Objectives: This study aimed to determine whether a mobile health (mhealth) intervention is effective in reducing weight and changing dietary behavior among employees with overweight and obesity. The study also investigated whether engagement with the intervention affected its effectiveness. Methods: The intervention involved the use of a dietary coaching app, a wearable device for monitoring physical activity and body composition, and a messenger app for communicating with participants and an intervention manager. A total of 235 employees were recruited for a 12-week intervention from eight workplaces in Korea. Questionnaire surveys, anthropometric measurements, and 24-h dietary recalls were conducted at baseline and after the intervention. Results: After the intervention, significant decreases in the mean body weight, body mass index, body fat percentage, and waist circumference were observed. Furthermore, the consumption frequencies of multigrain rice and legumes significantly increased, whereas those of pork belly, instant noodles, processed meat, carbonated beverages, and fast food significantly decreased compared with those at baseline. The mean dietary intake of energy and most nutrients also decreased after the intervention. When the participants were categorized into three groups according to their engagement level, significant differences in anthropometric data, dietary behaviors, and energy intake were observed following the intervention, although there were no differences at baseline, indicating that higher engagement level led to greater improvements in weight loss and dietary behavior. Conclusions: The intervention had positive effects on weight loss and dietary behavior changes, particularly among employees with higher engagement levels. These results indicate the importance of increasing the level of engagement in the intervention to enhance its effectiveness. The mhealth intervention is a promising model for health promotion for busy workers with limited time.

• Advances in concrete construction
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• v.15 no.3
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• pp.203-213
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• 2023

New techniques, technologies, and materials should be used to design and build sports stadiums. Since this century, much progress has been made in covering the roofs of sports stadiums, and the possibility of accurate computer calculation has been provided for stadiums, so by choosing a new structure, we can double the beauty and resistance of these stadiums. A stadium has an excellent and valuable design when its structure, shell, building, materials, and joinery follow a high architectural idea at all levels and scales. This article examines the mechanical performance of polymer cement strength in the construction of football stadiums, along with their structural knowledge in the form of the best examples in the world. Portland cement is one of the most used materials for constructing football stadiums. However, its production requires spending a lot of money, wasting energy, and damaging the environment. Considering the disadvantages in the production and consumption of concrete in different environments, it is necessary to find alternative materials. It should be used with cheaper, simpler technology, abundant primary resources, energy saving, less environmental damage, and better chemical and physical properties in concrete. High-strength concrete technology is considered a new development in the construction industry of concrete structures. In hardened concrete, strength and durability are two main factors, and as the compressive strength of concrete increases, concrete becomes more brittle. As a result, its tensile strength does not increase in proportion to the increase in compressive strength and has less strain tolerance. For this reason, the need to use is evident from the fibers in high-strength concrete. Fibers are used in concrete to increase tensile strength, prevent crack propagation, and significantly increase softness. The increase with the change of these resistances depends on the strength of concrete without fibers, the shape of fibers, and the percentage of fibers. This cement is obtained from the wastes of chemical and petrochemical industries and the wastes from coal combustion, which have the properties mentioned as substitutes for Portland cement.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.42-56
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• 2005

Hyperlipidemia is one of the risk factors for coronary artery disease. Despite of epidemiological evidence that tea consumption is associated with the reduced risk of coronary heart disease, experimental studies designed to show that drinking tea affects blood lipid concentration or oxidative stress have been unsuccessful. The purpose of this study was to investigate whether functional tea (three servings/day) supplement with medical nutrition therapy (MNT) lead to a beneficial outcomes in mildly hyperlipidemic adults. From February to October, 2003, the 43 hyperlipidemic (23 men, 20 women) subjects (total cholesterol$\geq$200 mg/dL or triglyceride$\geq$150 mg/dL) admitted to K Medical Center were studied. Subjects were randomly divided into 3 groups; placebo tea (PT), half dose of functional tea (HFT), full dose of functional tea (FFT). During 12 weeks of study period, the subjects were given placebo or functional tea daily with MNT. Anthropometric measurements, blood chemical analysis including lipid levels, total superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels, and dietary assessment were carried out at the beginning and end of experiment. The effects of functional tea were compared with the placebo in randomized clinical trial study. The placebo was prepared to match with the functional tea in color and taste. After the 12 weeks of MNT, the subjects had regular and balanced meal pattern. Consumption of foods high in cholesterol and saturated fat, salty foods, fried foods, and instant foods decreased significantly in all three groups (p<0.05). Intake of energy and cholesterol also decreased (p<0.05). Drinking three servings per day (390 mL/day) of functional tea significantly reduced the levels of blood triglyceride (HFT, 42.5%; FFT, 29.4%), total cholesterol (HFT, 8.5%; FFT, 13.7%), and atherogenic index (HFT, 14.6%; FFT, 21.7%). Whereas no changes were found in the LDL-, HDL-cholesterollevels, and LDL/HDL ratio. Plasma homocysteine (Hcy) concentration decreased significantly (p<0.05) in functional tea groups (HFT, 14.9%; FFT, 14.1%). SOD increased significantly (p<0.05) in HFT (8.3%). GSH-Px increased significantly (p<0.05) in FFT (12.8%). In conclusion, the MNT improved the dietary habits, in addition, functional tea supplement decreased blood lipid levels and Hcy, and increased SOD and GSH-Px levels. These results indicate that functional tea consumption may decrease the risk of cardiovascular disease via improving blood lipid levels and antioxidant status.

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.105-116
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• 2014

Surveys on the consumption of caffeinated beverages by high school students (n=886) were performed. Of the students, 97.0% consumed a variety of caffeinated beverages, including carbonated drinks (90.0%), processed milk and cocoa (79.0%), coffee (63.0), teas (52.1), energy drinks (16.4%) and nourishment drinks (15.5%). The frequency of intake per student was 8.2 times per week. Caffeine intake through the caffeinated beverages was 41.53 mg/day, which was accounted for by coffee (51.5%), carbonated drinks (19.6%), processed milk and cocoa (11.5%), teas (11.4%), energy drinks (5.0%) and nourishment drinks (1.1%). Students with high levels of stress, those who consumed snacks twice a day, and those who used a computer (or smart phone) for more than 3 hours per day showed significantly higher caffeine intake. The groups with high caffeine intake experienced heart palpitations, insomnia and pollakiuria. Students indicated that they consumed the caffeinated beverages for the taste (57.9%), waking up (18.0%), thirst (13.2%), etc. (10.9%). They tended to consume drinks with a high content of caffeine to sleep less. In addition, they rarely checked the label, and showed a lack of awareness of the caffeine contents in the beverages, which calls for education.