• Journal of Soil and Groundwater Environment
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• v.6 no.3
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• pp.43-52
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• 2001

It is important that the gas collected from wells completed in waste landfill should be continuously and stably transported to pre-treatment stage through pipelines. The transport is generally affected by fluid flow characteristics of landfill, gas reserves, leachate moisture holdup in pipeline, structures and dimensions of pipeline network, etc. This paper analyzes the pipeline transport and collection mechanism for gas generated in a durable waste landfill. From the results, the optimal controlled scheme of blower inlet pressure is proposed for the prevention of trapped gas pocket zones.

• The Journal of Advanced Prosthodontics
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• v.3 no.1
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• pp.25-32
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• 2011

PURPOSE. The purpose of this study was to assess the prevalence and extent of clinical attachment loss of periodontal tissue and to find out variables related to clinical attachment loss (CAL) in Korean adults older than 40 years of age. MATERIALS AND METHODS. Data were collected from 2,519 subjects who were part of a cohort study conducted in Ansan city by Korea University Medical School for Korean Genome project. Age, sex, smoking, drinking, fast glucose, blood pressure, obesity and total cholesterol levels were examined. The oral examination included probing pocket depth, gingival recession and CAL of Ramford's teeth. The severity of periodontitis was classified based on the mean value of CAL. The relationship between each risk factor and the severity of CAL was independently estimated using the chi-square test, the test or one-way ANOVA. Multiple regression analysis was used to determine the significance of each factor in the periodontal disease. RESULTS. The prevalences of clinical attachment between 1 and 3 mm, between 3 and < 5 mm, and ${\geq}$ 5 mm were 80.27%, 16.75% and < 1%, respectively. Although the univariate analysis showed age, gender, smoking, fasting glucose, blood pressure and total cholesterol levels were significantly related to the severity of CAL, multiple regression analysis indicated that age (P < .0001), gender (P < .0001) and smoking (P < .05) were only significantly related. CONCLUSION. Older age, male gender and smoking were significant risk factor for the increase of CAL, and these may be useful indicators of periodontitis high-risk groups.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.1
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• pp.11-20
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• 2004

Problem : The several studies were reported to the effects of individual tooth tray with the parallel tooth, but not reported to the effect of individual tooth tray with severe undercut in impression making. Purpose : The purpose of this study is to examine the effect of individual tooth tray; 1) the accuracy of impression in terms of distance. 2) reproducibility of pocket. Material and methods : In this study, a metal model with 3 teeth including tooth prepared 30-degree undercut and gingival crevice of the depth 5mm, width 0.4mm was cast. Impressions of the metal model were taken in 5 times used 4 kinds of impression materials with individual tooth tray and another impression taking were made with conventional method without individual tooth, used same materials, procedure. The stone models were made. Distances between abutments were measured with a Micromeasurescoup-mm. Result : The following results were obtained ; 1. In the comparisonof inter-abutment distance between parallel tooth without individual tooth tray, 4elastomeric materials have not significant difference to the metal model(p>0.05). 2. In the comparisonof inter-abutment distance with undercut tooth without individual tooth tray, 4elastomeric materials have a significant difference to the metal model(p<0.05), especially polyether's dimensional change is large. 3. If individual tooth tray was used to take impression in abutment teeth with severe undercut, more stable results was achieved easily than conventional method. (p>0.05). 4. It is not true that the pressure of impression material with individual tooth tray increased to gingival sulcus. Conclusion : By the results, I knew the fact that individual tooth tray was useful impression method on the teeth with severe undercut for the dimensional stability. Also, I could not confirm the fact that individual tooth tray would increase the penetrating pressure into cervice.

• Korean Journal of Community Nutrition
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• v.3 no.2
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• pp.228-244
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• 1998

The nutritional status of 362 elderly men and women in Chung-bud area was evaluated in terms of their nutrient intakes, biochemical and anthrophometric measurements by interviews with questionnaires from August to October 1996. Mean intake of all nutrients except ascorbic acid did not meet the RDA for this sample. Protein, vit A, reboflavin, calcium were the most likely to be deficient on the basis of propotions of elderly consuming less than 75% of the RDA. The subjects nutrient intake was significantly affected by gender, marital status, number of family, family composition, educational level, pocket money, and region. Men in rural areas and women over 75 in urban areas were the most vulnerable groups with nutritional deficiency. According to serum biochemical indices, mean level of cholesterol, triglycerides, LDL, total protein, albumin and iron belonged to normal range but mean level of HDL showed below the normal range. More elderly men and women in urban areas showed a higher percentage of abormal level of cholesterol, triglycerides, LDL and HDL than those in rural areas. More elderly men and women in rural areas had abnormal levels of RBC, Hematocrit and hemoglobin compared to those in urban areas. Mean height and weight of elderly men was 161.4cm and 56.2Kg, respectively and 149.1cm and 50.5kg for women. The elderly in rural areas were taller than those in urban areas but had less weight, MAC, TSF, MAMC. Mean BMI of this sample belonged to normal range. However, the elderly in rural areas had a higher rate of underweight and lower for overweight than those in urban areas. The elderly in urban areas had higher blood pressure than those in rural areas.

• Journal of Chest Surgery
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• v.12 no.3
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• pp.297-305
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• 1979

Occlusive coronary artery disease presents a potential threat to a significant population in the United States. According to many case reports, the increasing incidence of coronary artery disease due to atherosclerosis is noted in Korean, recently. Operative vascular procedures have increased steadily in number over the past 20 years in the United States. There have been many isolated case reports about coronary artery surgery, but these had little clinical impact. Nowadays, major three coronary bypass surgery has developed principally at three cardiac centers in the United States since 1967. Among three coronary bypass operation, the aorta-coronary artery saphenous vein bypass graft was first demonstrated by Favolaro and Effler at the Cleveland Clinic in 1967. We experienced one case of coronary artery disease, which was treated successfully by aorta-coronary saphenous vein graft with mild hypothermia under extracorporeal circulation in May, 1977. Saphenous vein was removed from above the knee and was 2.5 mm in diameter. The left ventricle was not vented for the left ventricle was not overdistended. Temporary artificial pace-maker-Medtronic-was implanted for the prevention and treatment of post-operative arrhythmia and heart block in post-operative first day. He is a 57 year old male businessman who had been suffered from hypertension [200 mmHg in systolic pressure] since 4 years ago, who had intermittent conservative treatment at local clinic. He had been afflicted with severe chest pain with choking sensation for 50 days. This symptom was aggravated exposing cold weather, or cold water, but was respond to rest. Pre-operative ECG revealed no any other ischemic sign except sinus bradycardia. Significant S-T segment depression was noted at lead II, AVF after double 5 minutes exercise, indicating positive Master`s test. Serum cholesterol was slight elevated to 253 mg/dl. Final pre-operative diagnosis was made by coronary arteriogram, which showed about 1.0-cm segmental 90 % occlusive atherosclerotic lesion in the proximal part of right coronary artery above the origin of acute marginal artery. Left coronary artery revealed good patency and there was no collateral circulation between right and left coronary artery .Hospital course was not eventful. He was discharged with good result on the post-operative day. He has been free from chest pain for longer than 2 years. And also the arterial flow in the coronary bypass graft is auscultated with the pocket-sized ultrasonic velocity detector, which shows the patency of the coronary bypass graft good.

• Korean Journal of Materials Research
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• v.25 no.11
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• pp.616-621
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• 2015

Atmospheric pressure plasma is used in the biological and medical fields. Miniaturization and safety are important in the application of apply atmospheric plasma to bio devices. In this study, we made a small, pocket-sized inverter for the discharge of atmospheric plasma. We used pulse power to control the neutral gas temperature at which the, when plasma was discharged. We used direct current of 5 V of bias(voltage). The output voltage is about 1 to 2 kilo volts the frequency is about 80 kilo hertz. We analyzsed the characteristics of the atmospheric plasma using OES(Optical emission spectroscopy) and the Current-Voltage characteristic of pulse power. By calculating of the current voltage characteristics, we were able to determine that, when the duty ratio increased, the power that actually effects the plasma discharge also increased. To apply atmospheric plasma to human organisms, the temperature is the most important factor, we were able to control the temperature by modulating the pulse power duty ratio. This means we can use atmospheric plasma on the human body or in other areas of the medical field.

• Elastomers and Composites
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• v.38 no.3
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• pp.195-205
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• 2003

This paper presents an analytic method and a design technique for golf shoes with air-cycled pump in the midsole. The golf shoes are modeled using the finite element method for better design by considering the configuration of the midsole and the outsole, which compose the golf shoes. Also the optimum size and shape of air-cycled pump in the midsole is examined. The values or standard human pressure for boundary conditions are adopted for the FEA(Finite Element Analysis). The unknown constants of the strain energy function of Ogden type are observed in accordance with the axial tension test. By the commercial FEM software for nonlinear analysis, MARC V7.3, the strains and the values of volume change for the midsole and the outsole are obtained, respectively. It can be concluded that results obtained by FEM in the midsole and the outsole are different depending on the characteristic of elastomer The results reported herein provide better understanding of analyzing the golf shoes. Moreover, it is believed that those properties of the results can be utilized in the shoes industry to develop the effective design method.

• Journal of the Korean Geographical Society
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• v.30 no.3
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• pp.230-241
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• 1995

The Characteristics of nocturnal temperature fields were analyzed to understand the factors of freezing-and-cold damages on orange orchards in Cheju Island. Temperatures were measured from January 7th through 27, 1995 at 25 sites in an area of 1x1.25$ extrm{km}^2$, Wasan-ri, Chochon-up, Pukcheju-kun located on the northeastern slope of Mt.Hanla. Several other weather elements such as wind and cloud were observed as supplementary data. Surface weather maps were also analyzed to clarify the influence of prevailing pressure patterns on the temperature fields. The vertical temperature profiles were obtained at the height from the ground up to 360 cm in 30 cm intervals at site 3, a frost hollow, and site 10 on the upper slope. The results show that freezing damages occured in the hollows, terrain depressions, rather than at the upper slope due to nocturnal radiation cooling as well as accumulation of cold airflow from Mt.Hanla. Windbreaks of densely planted Japanese ceders with stone-walls also roled as obstacles to the cold airflow in nights with Clear skies and light winds. The maximum intensity of temperature inversion in hollows, quasi-cold air lake, was 3.1$^{\circ}C$. Cold air from Mt.Hanla was trapped in the depressions up to a height of 90cm forming frost pocket. Man-made facilities such as shelterbelt or stone-wall which are built to prevent the penetration of cold north-westeries in winter aggravated the cold damage. The differance of daily minimum temperatures between before and behind shelterbelts was 2.$0^{\circ}C$. The man-made convection by smudgin which raised the temperatures up to 3.8$^{\circ}C$ can reduce the cold damage in the hellows.

• Journal of the Korean Society of Food Culture
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• v.11 no.3
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• pp.305-316
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• 1996

The purpose of this study was to find out how much they have several aspects of food related knowledge and eating behaviors of high school students in Sungnam area. The self-administrated questionnaire was used. The result were as follows: 1. The average height of boys and girls was $172.6{\pm}0.7$ cm and $156.3{\pm}1.5$ cm respectively. The average weights of them were $62.4{\pm}0.5$ kg (male) and $47.2{\pm}0.8$ kg (female). BMI (Body Mass Index) of them were $20.74{\pm}0.14$ (male), $18.82{\pm}0.28$ (female). The average age is 16.7 years old. 2. The 66.5% of the subjects were spent more than one-third of their pocket money in buying on light meals during three times a week. There were significant differences between income level of family. Boys spent more money on each meal than girls. And significant differences were also obserbed by their residence area and Bundang residences spent more in buying snacks. 3. The rate of skipping meals was 51.2% in boys compared with 68.0% in girls. The frequencies of buying snacks instead of main meal were high in girls. Time limits in eating may possibly be the main reason for skipping meals (59.8%), especially in the morning. Skipping a breakfast becomes general eating habits in high school students, because of pressure for time to go to school. 4. It is required that parents should be taught to prepare balanced lunch box for their children because the rate of students who prepared two lunch boxes are 49.4%. 5. The students took snacks once or twice a day. They usually bought snacks in school concessions (51.8%) and they selected items of snack instinctivly. The girls ate snacks during lunch break time (31.7%) and after dinner (23.6%). Boys ate snacks after dinner (29.1%). Preference of foods were different by sex. Boys preferred bread (31.7%), milk and otherdairy products (80.8%), cola and soda (42.0%) as their snacks between meals. Girls selected biscuit, chip, beverage, coffee as their snacks, frequently. 6. BMI value of the group who ate between meals more than three times a day was lower $(18.78{\pm}0.65)$ than that of the group who ate nothing between meals $(20.71{\pm}3.79)$. 7. As for the nutritional knowledge, the students generally had higher correct rate of answer about which nutritive components of food has (76.6%). But they had lower knowledge on questions of nutritive values in food (10.6%). There was a meaningful relation between favorite food and nutritional knowledge. In conclusion, there were some problems on nutritional knowledge and eating habits among the high school students. Therefore, it was required that girls should be learned to recognize the importance of breakfast and needed to select balanced meals and snacks. And it was required that the nutrition education should be complemented to motivate and improve practical eating behaviors.