• Journal of Environmental Health Sciences
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• v.23 no.2
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• pp.57-63
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• 1997

This study was carried out to find the adverse health effects of ozone by papers, the potential indoor sources of ozone by papers, and then the removal mechanism of ozone by experiments. The exposure of individuals to excessive levels of ozone both in the industrial and ambient environment is a continuing public health concern. Ozone indoors may play a role in generating secondary pollutants that may have adverse health effects. The removal efficiency of ozone was studied by (1) the effect of concentration on breakthrough time, (2) the effect of flow rate on breakthrough time, (3) the effect of adsorbent's weight on breakthrough time, (4) the effect of temperature on breakthrough time, (5) the application of Langmuir's isotherm equation in using activated carbon. The followings are the conclusions that were derived from this study. 1. In the effect of concentration on breakthrough time, the adsorption capacity of activated carbon was inversely proportional to ozone concentratuion (0.1, 0.2, 0.3 ppm). 2. In the effect of flow rate on breakthrough time, the service life of activated carbon was inversely proportional to flow rate (2, 8, 14l/min). 3. The difference in removal efficiency of ozone between weights(100 mg and 150 mg) was seen. And when weight of activated carbon was 100 mg and 150 mg, pressure loss was 4-5mmHg and 6-7mmHg, respectively. It is required to study relations among flow rate and adsorbent's weight and ventilation quantity, too. 4. Generally, Langmuir's equation, one of the oldest and most used frequently isotherm equation, applies to chemisorption. In case of ozone, when the weight of activated carbon was 70 mg and temperature 40, slope(1/a) was $6.25\times 10^{-1}$ and intercept(1/ab) was $1.9\times 10^{-4}$ (average r=0.94).

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.297-304
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• 2017

Although adolescents' obesity prevalence increases recently in Korea due to Westernized dietary life, according to social and economic development, and physical activity decline, distorted body image and improper dietary habits are prevalent, because of excessive obsession with weight control, deriving from psychological impacts including appearance supremacy. This study conducted a survey on health oriented awareness and attitude related with dietary habits targeting adolescents, such as high school students and college students, younger than 24, from May 11 to May 29, 2015. In this study, 280 questionnaire copies were collected out of 300 distributed questionnaire copies, and used 269 copies as analysis data, except 11 copies of which responses were inadequate. The results of this study are as follows: First, the high school students showed higher dietary regularity than the college students. Especially, 95.5% of the college students showed very high irregularity of lunch, compared with just 4.5% of the high school students. Second, the adolescents showed distorted perceived body image in comparison with body mass index (BMI). As a result of examining BMI relationship, according to one's own perception on body type, 28.6% of the respondents perceived themselves fat, despite normal BMI, and 40.4% of the respondents perceived themselves normal, despite low BMI. Third, health behavior activities level was higher, as the regularity of breakfast (B=1.093), lunch, (B=0.650), and dinner (B=0.765) was higher. The variable affecting the most ( ${\beta}=0.372$) was the regularity of breakfast. As interest in weight control was higher, health behavior activities was lower. Because over-interest in weight control may be linked with improper dietary habits or weight control, a caution is needed. The results of this study are expected to be utilized as the basic data for the policy and health-oriented program development to improve adolescents' health behavior practice.

• Journal of Nutrition and Health
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• v.27 no.10
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• pp.1048-1057
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• 1994

Nonobese NIDDM patients were studied were studied with respect to changes in visceral protein status, serum glucose and lipids and insulin secretion capacity before and after intake of enteral formula. Patients with renal or hepatic disease, gastrectomy, malabsorption, weight gain over past 6 months and poorly controlled blood glucose level were excluded. Eighteen patients served as case and administered, in addition of their usual diet, 400ml of enteral formula for 8 weeks. Another 18 patients participated in controls and had usual food intake for 8 weeks. In the begining, the levels of fasting and postprandial glucose, glycated hemoglobin, triglyceride, HDL, LDL, total cholesterol, albumin, total protein and transferrin and glucose response area on oral glucose tolerance test were not different between two groups. The response areas of insulin, C-peptide and free fatty acid and serum IGF-1 level were higher in the case than in the control group. Energy intake of patients given enteral formula exceeded their estimated energy requirements(108%) and they consumed a mean of 112g protein per day. Patients given enteral formula showed an increase in body weight(4.4%), serum transferrin(10%), IGF-1(13%) and triglyceride(34%) while controls showed no changes in those parameters at 8 weeks compared to initial values. There were no significant changes after 8 weeks in the levels of glucose, glycated hemoglobin, HDL, LDL, total cholesterol, total protein and albumin and response areas of glucose, insulin, C-peptide and free fatty acid in both groups compared to initial values. This study suggests that nutrition supplement with enteral formula can increase body weight and visceral protein status in nonobese NIDDM patients without changes in blood glucose. However, excessive calorie intake could temporarily increase serum triglyceride. In addition, this study indicates that serum transferrin and IGF-1 are more sensitive indicators to changes of protein intake than serum albumin and total protein.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.3
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• pp.219-226
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• 2005

In this study, the problem formulation and solution technique using genetic algorithms for design optimization of laminate composite cylindrical beam section are presented. The hollow cylindrical beams we usually used in the wheel chair. If the weight of wheel chair is reduced, it will lead to huge improvement in passenger's mobility and comfort. In this context, the replacement of steel by high performance and light weight composite material along with optimal design will be a good contribution in the process of weight reduction of a wheel chair. An artificial genetics approach for the design optimization of hollow cylindrical composite beam is presented. On applying the genetic algorithm, the optimal dimensions of hollow cylindrical composite beams which have equivalent rigidities to those of corresponding hollow cylindrical steel beams are obtained. Also structural analysis is conducted on the entire wheel chair structure incorporating Tsai-Wu failure criteria. The maximum Tsai-Wu failure criteria index is $0.192\times10^{-3}$ which is moth less than value of 1.00 indicating no failure is observed under excessive loading condition. It is found that the substitution of steel by composite material could reduce the weight of wheel chair up to 45%.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.397-402
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• 2003

Generally, container arrangement has been carried out based on the Classification guidelines. However, guidelines provide only container securing forces for the given container arrangement and Classification requirements of the forces. In order to design container arrangement additional information is needed such as container securing forces and arrangement that accounts for lashing bridges, vertical lashing, vertical center of gravity (VCG), and maximum stack weight. Trial and error method using the existing guidelines requires excessive amount of calculation time and cannot provide accurate results of the calculations. In order to fulfill this need, a new container securing system has been established based on the equilibrium conditions that include lashing bridges and vertical lashing. An optimization algorithm has been developed for the new system since current optimization methods such as genetic algorithms and evolution strategies are unsuitable for the container securing problems, which involve equality constraint. Design variables are container weights of tier and objective function is either total container weight or VCG of a stack. The newly developed system provides optimum arrangement of containers for both maximum stack weight and maximum VCG. It also greatly reduces time for designing container arrangement.

• Journal of Nutrition and Health
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• v.22 no.1
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• pp.1-8
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• 1989

The study was attempted to observe effects of voluntary exercise on energy expenditure and on storage of excessive energy into body fat in adult mice. Mice, body weight 25-30g, were divided into two groups, exercise and sedentary group. Voluntary exercize by running wheel was allowed for former group but not for the mice of the latter group which were restricted by limiting space allowance 13.5$\times$11.5$\times$15.0cm per mouse. During a period of 4 weeks of feeding trial, they were fed ad libitum starch-casein based diet added with $^3\textrm{H}$-glucose (D-[1-$^3\textrm{H}$(N)]-glucose) at a level of 20 nCi per g of diet. Measurements were made to study hematology, lipase activity in epididymal adipose tissue, total contents of body waste and fat, and radiactivity of $^3\textrm{H}$-glucose incoporated into body fat. Dietary intake, body weight gain and amount of voluntary physical activities were also measured. The results obtained ard summarized as follows; 1) Amount of metabolizable energy intake, body weight gain and body fat were not statistically different between the two group. However, mice of the exercise group tended to show lower body weight gain body fat contants, but higher energy expenditure than those of the sedentary group. 2) Radioactivity of $^3\textrm{H}$-glucose incoporated into body fat appeared lower for exercise group expressd on a whole body fat basis. The activity was, however, higher for exercise group when expressed based on per g of fat compared to that of sedentary group. 3) Exercise group showed also higher activity of lipase in epididymal adipose tissue than the other group. 4) Mice whose physical activities were restricted appeared to have lower levels of hemoglobin and hematocrit values than of the exercise group. These results seem to support the theory that turn-over rate of body fat is activated by exercise and to suggest that consumed energy is to be converted primarily into body fat before its use as energy source by oxidation even during a period of continuous energy expenditure by exercise.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.1
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• pp.63-70
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• 2023

Purpose : Excessive alcohol causes damage to skeletal muscles, leading to the development of a specific disease entity called alcoholic myopathy. Chronic inflammation is related as an underlying mechanism for the loss of muscle mass induced by alcohol. Pro-inflammatory cytokines such as TNF-α (tumor necrosis factor-α) and IL-6 (interleukin-6) play a role in this process. The acupuncture point Feng Shi (GB 31) is located on the midline of the lateral aspect of the thigh, above the transverse popliteal crease. This acupoint is used for the treatment of weakness, atrophy, numbness, and post-stroke symptoms of lower limbs. The purpose of this study was to investigate the effect of Feng Shi stimulation on muscle atrophy caused by chronic alcohol administration. Method : Young male Sprague-Dawley rats were randomly divided into three groups of eight each: Normal, Control, and GB31. The rats in the Control and GB31 groups were orally given 25 % ethanol (5 ㎖/kg, body weight) daily for 4 weeks. The Normal group was similarly administered saline. The acupressure at Feng Shi was treated to rats in the GB31 group. After 4 weeks, the body weight, muscle weight and cross-sectional area of gastrocnemius were assessed and the histological changes in gastrocnemius muscle fiber were observed by hematoxylin and eosin staining. Moreover, TNF-α and IL-6 expressions were immunohistochemistrically evaluated. Results : Acupressure stimulation at Feng Shi had a protective effect on the weight reduction of the gastrocnemius muscle caused by alcohol intake, and had an effect of suppressing anatomical change in muscle fiber and decreasing the average cross-sectional area. Also, the immunoreactivities of TNF-α and IL-6 in the GB31 group were decreased. Conclusion : These results suggest that acupressure at Feng Shi has protective effects on chronic alcohol-induced muscle atrophy by inhibiting pre-inflammatory proteins such as TNF-α and IL-6.

• Journal of Environmental Impact Assessment
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• v.8 no.2
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• pp.65-71
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• 1999

Characteristics of food garbage discharged from primary schools in Seoul Metropolitan city were analysed from a recycling point of view. The results of study are epitomized as follows : 1. Factors of generation of food garbage are mainly an unbalanced diet habit, indifference of class teachers, and worn-out cooking equipments. 2. Measures of reduction are principally a written message to parents, broadcasting in the school, and instructions. 3. Methods of recycling are mainly feed stuff, composting by school itself, composting on commission, and making feed stuff on commission. 4. Obstacles of food garbage recycling are a nasty smell of composting apparatus, an excessive fuel consumption of composting apparatus, a high concentration of salt, and an unstable demand for feed stuff and compost produced from food garbage. 5. Correlation factors are like follows : the number of feeding children and food garbage weight after cooking is 0.35, total food garbage generated and monthly treatment cost of food garbage is 0.20, individual school lunch expenses and food garbage weight after cooking is -0.10, individual school lunch expenses and food garbage generated per capita is 0.02, and individual school lunch expenses and monthly treatment cost of food garbage is 0.03.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.4
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• pp.7-13
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• 2010

Linear motors are efficient mechanism that offers high speed and positioning accuracy. By eliminating mechanical transmission mechanisms, much higher speeds and greater acceleration can be achieved without backlash or excessive friction. However, an important disadvantage of linear motor system is its high power loss and heating up of motor and neighboring machine components on operation. Therefore, it is necessary to design moving table with high stiffness, high efficiency and light weight construction. This paper presents the development of moving table using composite material. In order to develop light weight construction of moving table, finite element analysis is performed to find best moving table construction and composite stacking sequence. NASTRAN and MINITAB were used as the optimizer. A prototype for the moving table using composite material was created.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.396-401
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• 1995

Epoxy coated reinforcing steels (ECRs) were acquired from ten sources and coatings from each source were initially characterized in terms of defects, thickness, solvent extraction weight loss and hardness. Testing involved exposure in three aqueous solutions at elevated temperature (8$0^{\circ}C$) and in chloride-contaminated concrete slabs under outdoor exposure, It was found that the density and size of coating defects was the promary factor affecting ECR performance. The equivalent circuit analysis using electrochemical impedance spectroscopy (EIS) data indicated that the impedance response for well-performing ECR specimens showed no signs of active degradation at the interface although diffusional processes similar to those noted for poorly performing bars occurred here. Experimental results also indicated a relationship between corrosion behavior and bar source. Weight loss upon solvent extraction correlated with impedance reduction from hot water exposure. Coating defects during most of the tests, especially in high pH solutions containing chloride ions. ECRs with excessive coating defects, either initially present or ones which developed in service, performed poorly in every test category regardless of source. Forms of coating failure were extensive rusting at defects, blistering, wet adhesion loss, cathodic delamination, underfilm corrosion and coating cracks. These occurred sequentially or concurrently, depending on the condition of the ECR and nature of the environment