• Journal of the Korean Ceramic Society
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• v.42 no.8 s.279
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• pp.554-560
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• 2005

The engineering ceramic needs the properties of high strength, hardness, corrosion-resistance and heat-resistance in order to withstand thermal shock or applied nonuniform stresses without failure. The densely coated porous ceramics can be used for machine component, electromagnetic component, bio-system component and energy-system component by their high-performances from superior coating properties and light-weight characteristics due to the structure including pore by itself. In this study we controlled the porosity of silica and alumina, $8.2\~25.4\%$ and $23.4\~36.0\%$, respectively, by the control of sintering temperature and starting powder size. We made bilayer structures, consisting of a transparent glass coating layer bonded to a thick substrate of different porous ceramics by a thin layer of epoxy adhesive, facilitated observations of crack initiation and propagation. The elastic modulus mismatch could be controlled using different porous ceramics as the substrate layer. Then we applied 150 N force using WC sphere with a radius of 3.18 mm by Hertzian indentation. As a result, the crack initiation in the coating layer was delayed at lower porosity in the substrate layer, and the damage in the coating layer was relatively smaller at the bilayer structure coated on higher elastic substrate.

• Health Policy and Management
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• v.26 no.1
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• pp.12-23
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• 2016

Background: Many studies have explained regional disparities in health by socioeconomic status and healthcare resources, focusing on differences between urban and rural area. However some cities in Korea have the highest cardiovascular mortality, even though they have sufficient healthcare resources. So this study aims to confirm three hypotheses. (1) There are also regional health disparities between cities not only between urban and rural area. (2) It has different regional risk factors affecting cardiovascular mortality whether it is urban or rural area. (3) Besides socioeconomic and healthcare resources factors, there are remnant factors that affect regional cardiovascular mortality such as health behavior and physical environment. Methods: The subject of this study is 227 local authorities (si, gun, and gu). They were categorized into city (gu and si consisting of urban area) and non-city (gun consisting of rural area), and the city group was subdivided into 3 parts to reflect relative different city status: city 1 (Seoul, Gyeonggi cities), city 2 (Gwangyeoksi cities), and city 3 (other cities). We compared their mortalities among four groups by using analysis of variance analysis. And we explored what had contributed to it in whole authorities, city and non-city group by using multiple regression analysis. Results: Cardiovascular mortality is highest in city 2 group, lowest in city 1 group and middle in non-city group. Socioeconomic status and current smoking significantly increase mortality regardless of group. Other than those things, in city, there are some factors associated with cardiovascular mortality: walking practice(-), weight control attempt(-), deficiency of sports facilities(+), and high rate of factory lot(+). In non-city, there are other factors different from those of city: obesity prevalence(+), self-perceiving obesity(-), number of public health institutions(-), and road ratio(-). Conclusion: To reduce cardiovascular mortality and it's regional disparities, we need to consider differentiated approach, respecting regional character and different risk factors. Also, it is crucial to strengthen local government's capacity for practicing community health policy.

• Toxicological Research
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• v.16 no.3
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• pp.211-219
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• 2000

The therapeutic effect of AS2-006A, a derivative of asiaticoside, has been studied and is being developed as a new wound-healing agent. In the present study, the general pharmacological effects on 1) central nervous system, 2) autonomic nervous system, 3) respiratory system, 4) gastrointestinal system. 5) cardiovascular system. and 6) urinary system were assessed in experimental animals and in in vitro models. 1. In vivo animal study: External applications of the 1 % gel ointment of AS2-006A to rats at the doses of 200. 600 or 2000 mg/kg body weight showed no observable pharmacological effects. The effects on the central nervous system were assessed by observation of behavior, hexobarbital-induced sleeping time, pentetrazole-induced convulsion assay, body temperature measurements, and observations on spontaneous activity and catalepsy. The gel ointment exhibited no effects on the cardiovascular system (i.e. blood pressure and heart rate), renal physiology (i.e. urine volume and electrolytes excretion) and gas-trointestinal physiology (i.e. intestinal charcoal propulsion and gastric mucosal irritation). 2. In vitro experiments: The effects of AS2-006A on the physiology of smooth and cardiac muscles were assessed. Muscle contractions were isotonically and isometrically measured in organ chambers using a physiograph. Cumulative additions of AS2-006A (10$^{-9}$ -10$^{-5}$ M) induced no changes in the tension of isolated guinea pig ileum and tracheal muscles. AS2-006A only slightly increased contractility of rat atrial and papillary muscles at 10$^{-2}$ M, which was not statistically different from control. These data showed that the gel ointment of AS2-006A could be externally applied as a wound-healing agent with no potential side effects.

• Journal of the Korean Society of School Health
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• v.19 no.2
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• pp.59-74
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• 2006

Purpose : The principal objective of this study was to develop adequate health promotion programs satisfying the needs of high school students by exploring a variety of factors that affected their participation in these programs. This research was also designed to serve as preliminary data for the development of health promotion programs that will encourage active student participation. Methods : The study used a descriptive correlational design. The study participants were 658 coeducational high school students in Seoul, consisting of 317 9th graders and 341 10th graders. For this study, 599 structured questionnaires were selected. The survey was conducted for the period from December 12, 2005 to December 23, 2005. Results : Overall, students surveyed in this research showed relatively active participation in health-promoting behaviors. Among 5 dimensions, interpersonal support received the highest score while health responsibility ranked the lowest. Another finding was that posture correction program enjoyed the strongest student participation (75.5%) followed by stress management program(70.1%) and weight control program (56.6%). On the other hand, the participation rates for no-drinking(12.9%), smoking cessation program(17.0%), and influenza prevention program(22.9%) were at the low end. Multiple logistic regression results indicate that the higher interpersonal support score of health promoting behaviors gets, the higher student participation becomes. Conclusion : The study demonstrated that student participation was determined by the nature of health-promoting programs, demographic characteristics and health related physical fitness. It also showed that the sub-scales of the programs played a bigger role in student participation. Keeping this in mind, a wealth of health-enhancing programs of distinguishing qualities need to be tailored to meet various needs of students. In addition, serious efforts should be made to motivate them to seek relevant health promotion programs.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.9
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• pp.1474-1480
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• 2018

Objective: Isoquinoline Alkaloids, derived from one plant (Macleaya cordata) can be an alternative when it is desired to increase performance in feedlot cattle. However, results on these nutritional additives in high energy diets in ruminants are still incipient in literature. In this context, the objective of this study was to evaluate performance and carcass traits of feedlot bulls supplemented with sanguinarine, the main alkaloid presents in Macleaya cordata in high energy density diets. Methods: Thirty-two crossbred Angus-Nelore bulls with mean initial body weight of $365{\pm}10kg$ and mean initial age of $11{\pm}3$ months were used. The experiment lasted 119 days, with 14 days of adaptation and 105 experimental days. Experimental diet consisted of 85% whole corn grains and 15% protein-vitamin-mineral nucleus and supplied ad libitum. Treatments consisted of a control diet (CON) and a diet with sanguinarine supplementation (SAN) at a dosage of 4 g of product sufficient to provide 6 mg of sanguinarine/d. Experimental design was completely randomized. Results: Dry matter intake, average daily gain and feed conversion were similar (p>0.05) between treatments. However, SAN group animals had higher carcass yield (p = 0.045) and were more efficient in the transformation of dry matter consumed in carcass gain (p = 0.046) than CON. In addition, haptoglobin, increased throughout feedlot duration meaning high challenge for the animals due to the diet, but this behavior was similar (p>0.05) between treatments. Conclusion: Sanguinarine produced positive results in relation to carcass yield and could be used as an additive for bulls fed diets receiving high energy density diet.

• Korean Journal of Community Nutrition
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• v.5 no.3
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• pp.502-512
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• 2000

A survey was conducted on 222 students in two elementary schools in rural areas, one was a rural small city and the other was in the countryside. By measuring their skin-foldness in 4 spots by caliper, the body fatness of 5 grades(BFGr) of the subjects was resulted as follows ; 28.0% of boys and 6.7% of girls were classified as obese the and 34.1% of boys and 31.1% of girls as overweight. Comparing by region, children in the small city seemed to be fatter than the ones in the countryside(21.7% vs. 17.2% as obesity). Comparing by gender, boys were fatter than girls(28.0% vs. 6.7% as obesity). When recategorizing body fatness from 5 grades(BFGr) into 3 groups(BFGp) as overweight group(obesity+overweight), normal and underweight group(underweight+severe-underweight), we observed no significant difference in childrens dietary habits and food intake frequencies by BFGp. Overweight and underweight groups enjoyed snacking before dinner more frequently than the normal group(42.1-59.3% vs. 31.5%). The subjects showed poor nutrition knowledge score with relatively high attitude score about weight control and dietary behavior score was a little lower than the attitude score. Nutrition education programs, like camps, should stress on childrens nutrition knowledge. BFGp related to obesity attitude positive, a very low level and the latter related to diet, exercise and fasting attitudes at positive levels. Therefore overweight children seemed to be motivated easily. Also the higher the in exercise-value score, the more increased was shown in exercise attitude at positive, very low level. Emphasizing exercise-value in camp programs might make childrens exercise attitude more positive. As strategies for a rural obesity camp program are being developed by obese and non-obese children. The camp would be held over summer vacation for 3 days(2 nights) at the participants expence not exceeding 50,000 won. Contents of the program cover nutrition knowledge, and exercise-value as well as cooking lessons, exercise practice, and self-esteem enhencement.

• Korean Journal of Community Nutrition
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• v.12 no.5
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• pp.583-591
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• 2007

The purpose of this study was to assess the diet diversity, food habit and nutrient intake of obese adults who were visiting the health promotion center. This study was accomplished with the 138 obese adults (men = 103, women= 35) aged over 20 years old whose BMI were above $25 kg/m^2$. Nutrient adequacy ratio (NAR), the number of foods (Dietary Variety Score DVS), and food group consumed (Dietary Diversity Score, DDS) by using the data from the three days record were analyzed and the food habit and lifestyle were assessed by self reporting questionnaire. The average enemy intake of men was 2150.2 kcal which was significantly higher than that of women (p < 0.05). The intake ratio of carbohydrate, protein and fat over total energy was 54.8% : 19.3% : 25.8% in men, 59.5% : 17.8% : 22.6% in women respectively. Frequency of the breakfast in a week above 4, $2{\sim}3$ time and under one time was 75.7% 10.7% and 9.7% in men 77.1%, 5.7% and 14.3% in women respectively. frequency of eating between meals in a day under one time was 73.8% in men, 57.1% in women (p < 0.05). The average DDS and DVS was $3.63{\pm}0.07$ and $14.10 {\pm}3.45$, respectively which was significantly correlated with MAR (r=0.40 in DDS, r=0.64 in DVS, p < 0.01). The most frequent style of food pattern was DMGFV = 01101 in 35% of men, and DMGFV= 01111 in 37.1% of women. Our results show that dietary diversity and variety are useful parameters far evaluating nutrient intakes in obese adults. These findings suggest that nutritional education based on obese persons' eating behavior and eating diversity may be required to increase educational efficiency of weight control programs.

• Child Health Nursing Research
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• v.8 no.3
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• pp.322-333
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• 2002

Purpose: The purpose of study was : 1) to analyse the trend of research on the sensory stimulation in newborn in Korea, 2) to suggest direction for further study on the sensory stimulation in newborn and contributing to the use of intervention in newborn. Method: Research studies on the sensory stimulation in newborn were selected from the dissertations, parents-child health. Academic Society Journal, and from Korean Journal of Pediatrcs which were conducted between 1984 and 2002. The total numbers of the studies were 15. These studies were analyzed for 1) time of publication or presentation 2) thesis for a degree or nondegree 3) characteristics of subjects 4) sample size 5) research design 6) type of sensory stimualtion 7) meaurement tool 8) result. Result : 1)The most year of studies were the 1996's～ 2000's. 2) The degree of studies were higher than nondegree. 3) The most characteristics of subjects were the premature infants. 4) The most frequent sample sizes were 11-20. 5) The all research design was nonequivalent control group pretest-posttest design in quasi experimental basis. 6) The most type of sensory stimulation was Field massage(tactile and kinesthetic). 7) The measurement tool used all objective tools. 8) The most research data were collected by the measure of the weight, heart rate, behavior state, respiration, stress hormon and positive results. Conclusion: 1) Human sensory stimulation did not seem to harm the infants. 2) several positive effects of sensory stimulation that have been reported previously must be reevaluated. 3) further research will be required large sample size, long-term outcome, individualized stimulation program, early parent-infant contact in order to enhance the development of attachment, to determine the underlying mechanism and theorical frame for these stimulation effect.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.6
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• pp.84-92
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• 2005

This paper is concerned with optimum design of a center-pillar assembly induced by the high-speed side impact of the vehicle. In order to simulate deformation behavior of the center-pillar assembly, simplified finite element model of the center-pillar and a moving deformable barrier are developed based on results of the crash analysis of a full vehicle model. In optimization of the deformation shape of the center-pillar, S-shaped deformation is targeted to guarantee reduction of the injury level of a driver dummy in the crash test. Tailor-welded blanks are adopted in the simplified center-pillar model to control the deformation shape of the center-pillar assembly. The thickness of each part which constitutes the simplified model is selected as a design parameter. The thickness of parts which have significant effect on the deformation mechanism are selected as design parameters with sensitivity analysis based on the design of experiment technique. The objective function is constructed so as to minimize the weight and lead to an S-mode deformation shape. The result shows that the simplified model can be utilized effectively for optimum design of the center-pillar members with remarkable saving of computing time.

• Journal of Korean Society of Steel Construction
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• v.19 no.5
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• pp.527-537
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• 2007

The main girders and cross-beams of an H-beam bridge consisted of factory-made H-beams, providing better conditions for quality control. Also, on-site fabrication works can be minimized and most of the stiffeners can be omitted, enabling simple and economic construction. In this study, the effect of the Multi-Stepwise TPSM (M-TPSM) on improving the maximum span length and section efficiency is analyzed. Compared to a 30-m-long, five-girder conventional plate girder bridge, structural analysis results showed that 50.7~55.1% of the girder height and 24.1~26.2% of the self-weight may be reduced by the application of M-TPSM to a five-girder H-beam bridge constructed with H-$900{\times}300$beams. In case of conventional H-beam bridges without M-TPSM, it was found that seven girders are required for a similar level of load-carrying capacity. Therefore, it is concluded that by the application of the M-TPSM, the H-beam bridge would become one of most cost-competitive options for short- and medium-span bridges.