• Journal of Biomedical Engineering Research
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• v.38 no.6
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• pp.313-320
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• 2017

Myocardial infarction is a disease caused by stenosis of the coronary arteries. The high risk of sudden cardiac death due to myocardial infarction has triggered related researches that have been actively studied so far. However, these studies focused on the clinical results, which are mainly based on observations of symptoms due to infarction through electrocardiograms. Therefore, in this study, we tried to analyze the behavior of heart according to the position and volume of infarction lesion through the computer simulation study using three dimensional ventricular models. In order to implement infarction, commercial software was used to simulate cell necrosis due to blockage of a specific coronary. In addition, the conduction block due to infarction was mimicked by reducing the electrical conduction in the infarcted area, which was 100 times less than the electrical conduction of the whole ventricular lattice implemented by the finite element analysis method. Thus, this study classified the infarcted cases into the upper, middle, lower, and apex according to lattice data of eight different infraction areas. In other words, we assumed that myocardial infarction would have inherent electro-dynamic characteristics depending on the location and extent, and analyzed the ventricular electromechanical responses for infarction lesions using a three dimensional cardiac physiome model. The results showed that the volume of infarction did not directly affect the cardiac responses, but the location of the infarction lesions could influence the ventricular pumping efficiency. These suggest that the occlusion of specific coronary arteries may have a fatal effect on the decline in ventricular performance. In conclusion, although location of myocardial infarction lesions is considered to be an important variable to be considered clinically rather than lesion size, quantitative predictions should be made more in the future considering physiological factors such as lesion location and direction of myocardial fiber at that location.

• Journal of Nutrition and Health
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• v.34 no.6
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• pp.645-655
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• 2001

The purpose of this study is to investigate the dietary intake and bone mineral density(BMDs) in college women(n = 10), female swimmers(n = 10), and female weight lifters(n = 10). BMDs of lumbar spine(L2-L4), femoral neck, ward's triangle, and trochanter were measured with dual-energy X-ray absorptiometry. The results are summarized as follows. In swimmers and weight lifters, mean daily intakes of energy, protein, and fat were higher than those of college women and the intake of carbohydrate was significantly high in weight lifters. Also in swimmers and weight litters, mean daily intakes of animal flood, phosphorus, vitamin A, vitamin B$_1$, vitamin B$_2$, niacin, vitamin C, and cholesterol were found higher than those of college women but there was difference among the types of exercise. According to correlation analysis between nutrient intake and BMDs, intakes of energy, protein, carbohydrate, and vitamin B$_1$ were positively associated with BMDs of lumbar spines. According to stepwise multiple recession analysis, BMDs of lumbar spines were affected by intakes of protein, Fe, phosphorus, and vitamin B$_2$, also BMDs of femur were affected by each of vegetable protein, dietary fiber, and fe. from the above explanation, the nutrient intakes can be independent factor besides exercise. In conclusion, the weight lifting, resistant exercise, resulted in increase of both BMDs of lumbar spines and femur specially in growing and adult period of female. Whereas swimming lead to increase of BMDs of lumbar spine and decrease of BMDs of femur in female.

• Journal of Nutrition and Health
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• v.36 no.5
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• pp.491-499
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• 2003

Selenium is a strong antioxidant trace mineral, scavenging free radicals. The prevalence of chronic degenerative diseases is increasing in Korean adults with increasing age. The increased cell damage from free radicals has been implicated in the etiology of these diseases, and evidence is accumulating that the low selenium status that comes with advanced aged is involved in the prevalence of age-associated diseases. However, little is known about the selenium status of Koreans, its age-related change and its relationship to dietary nutrient intake. In this study, the serum selenium levels of healthy adult females according to life cycle and its association with blood albumin levels and nutrient intake were examined. Serum selenium level was measured with the Huwo research reactor using the neutron activation analysis method (NAA). The overall proportion of women with selenium deficiency, serum selenium concentrations below 7.0 $\mu\textrm{g}$/dl, was 9.4%. The average serum selenium levels were 12.39 $\mu\textrm{g}$/dl, 9.45 $\mu\textrm{g}$/dl and 9.16 $\mu\textrm{g}$/dl in the young adult, middle-aged and elderly groups, respectively, showing a reduction of selenium status with advancing age. Selenium deficiency was seen only in the elderly group. Generally, serum selenium levels positively or negatively correlated with nutrient intake, but these association patterns differed depending on the age. The nutrients that showed positive correlations with selenium levels were proteins and phosphate in the young adult group (p < 0.05, p < 0.05), and total calcium, potassium and vegetable-origin calcium in the middle-aged group. Vitamin C and fiber were the negative correlated nutrients with serum selenium levels in the elderly group (p < 0.05, p < 0.05). Multiple stepwise regression analysis of the determining factors responsible for selenium status showed that age and serum albumin levels were important factors which explained up to 26.9% variances in serum selenium levels. The average selenium concentrations of Korean adult female subjects were above the deficiency levels in all three age groups. There was a tendency toward decreasing selenium levels as the age of the subjects increased. The factors with the strongest in-fluence on selenium status in healthy adult Korean females were age and serum protein status. (Korean J Nutrition 36(5): 491~499, 2003)

• Journal of Nutrition and Health
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• v.42 no.6
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• pp.547-558
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• 2009

This study was carried out to compare the effect of smoking on dietary habits, nutrient intakes and blood lipid profiles in 173 adult male drinkers. Subjects were classified by two groups, alcohol-only and alcohol-smoking, based on their alcohol or smoking habits. The BMI of the alcohol-smoking group was significantly lower than those of alcohol-only group. In dietary habits, the alcohol-smoking group had higher irregular breakfast and dinner intakes than alcoholonly group (p < 0.05). Plant lipid intake of the alcohol-smoking group was higher than those of alcohol-only group (p < 0.05) and the vitamin C intake of the alcohol-smoking group was lower than those of alcohol-only group (p < 0.05). With regard to the diet quality evaluation of subjects, the alcohol-smoking group showed significantly lower values than alcohol-only group in the nutrient density of carbohydrate, dietary fiber, sodium, potassium, vitamin $B_6$, and vitamin C. Also, with regard to the index of nutrition quality (INQ) and the nutrient adequacy ratio (NAR), the alcohol-smoking group showed significantly lower value than alcohol-only group in vitamin C. With these results, we found that the alcohol-smoking group had lower diet quality evaluation. The results of blood analysis showed that HDL-cholesterol in the alcohol-smoking group was significantly lower than that in the alcohol-only group. In conclusion, the alcohol-smoking group had greater health risk than the alcohol-only group. Particularly, alcohol-smoking caused irregular eating patterns and unbalanced nutrition intakes compared to alcohol-only and also changed blood composition as shown in the decrease of HDL-cholesterol. Besides, the index of coronary heart disease such as AI was higher in both groups suggesting that alcohol-only or alcohol-smoking cause health problems. Since there is the limiting point in which the comparative analysis of non-drinkers and non-smokers is unable to be performed in this study, further wide research is needed on that matter.

• The Transactions of the Korea Information Processing Society
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• v.4 no.6
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• pp.1589-1600
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• 1997

The construction of optical access network costs upper 40% in total installation cost of total optical network. Optimization of access network therefore is core in optical network. Advanced countries include EU, Japan and USA already have researched access network. This paper presents analysis of three broad-band fiber-optics subscriber loop architectures(HFC, ATM-PON, Super PON). The analyses focus on the specific demonstrated architectures and use component cost projections to estimate future network costs on a per-subscriber basis. We use TITAN(Tool for Introduction Scenarios and Techno-Economic Evaluation of The Access Network) model. We find that ATM-PON can deliver voice and ISDN data at installed first costs than the other architectures. This is due to the sharing bandwidth among a cluster of subscribers within Curb. This work intends to support establishing guidelines for strategic decisions regarding the development of the access network alternatives of different operators.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.11
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• pp.927-936
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• 2014

This paper presents development and verification of the progressive failure analysis upon the composite laminates. Strength and stiffness of the fiber-reinforced composite are analyzed by property degradation approach with emphasis on the material nonlinearity and continuum damage mechanics (CDM). Longitudinal and transverse tensile modes derived from Hashin's failure criterion are used to predict the thresholds for damage initiation and growth. The modified Newton-Raphson iterative procedure is implemented for determining nonlinear elastic and viscoelastic constitutive relations. Laminar properties of the composite are obtained by experiments. Prediction on the un-notched tensile (UNT) specimen is performed under the laminate level. Stress-strain curves and strength results are compared with the experimental measurement. It is concluded that the present nonlinear CDM approach is capable of predicting the strength and stiffness more accurately than the corresponding linear CDM one does.

• Journal of the Korean Dietetic Association
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• v.6 no.2
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• pp.86-96
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• 2000

Food service management without nutrition education in school foodservice is hardly to improve nutritional status of school children. Therefore, this study was attempted to evaluate the effectiveness of nutrition education. The nutrition education was done for 82 5th grade children of 2 elementary school in Inchon. It has been performed for two month from Sep. 6 to Nov. 11, 1999. Also, to evaluate the effects of nutrition education, subjects were taken pretest for food habit, attitude, nutrition knowledge, and dietary intake through the questionnaires. The statistical analysis of data was completed using SPSS program. The results were summarized as follows : 1) The average height and weight for subjects are 141cm and 34.4kg. Most of the subjects had 2 siblings. 83.8% of the subjects has never been taken nutrition education. Otherwise, 85.2% of the subjects responded that they need a nutrition education. 2) For the food habit test results, the posttest mean scores increased. Food habit on vegetables showed significant difference between pretest and posttest(p<0.05). 3) The attitude test did not show the significant difference between pretest and posttest. 4) For the nutrition knowledge test result, the pre and posttest means were 47.59 and 57.12 respectively(p<0.001). 5) The correlations of food habit, attitude, and nutrition knowledge was positive relationship between food habit and attitude in the pre and posttest. 6) Intake frequency of foods increased for the most foods except meat, egg, milk, and drink as compaired pretest with posttest. Cereal, fish, and oil intake was significantly increased. 7) The intakes of most nutrients were increased, among which carbohydrate, fiber, calcium, and vitamin C intakes significantly different after education. The education period of this study was too short to improve their eating behavior and food choice and may need a long-term education and development of materials for nutrition education.

• Journal of the Korea Fashion and Costume Design Association
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• v.17 no.3
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• pp.73-84
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• 2015

Analysis of design preference to Korean and Chinese casual style were made targeting Chinese female students in Korea. The following conclusion was derived from the result of final 300-copy survey data, using SPSS 18.0 program. The data were analyzed by frequency, t-test, chi-squre independence test, ANOVA and Scheffe test. Firstly, when comparing change of design preference before the stay in Korea with after the stay in Korea, the biggest change in their preference was character casual style, while the least change was easy casual wear. In terms of duration of stay in Korea, the biggest change was from the group of over 3 years, and in the order of the group of 1-3years, and then lastly less than 1 year, which suggests that the longer the duration of stay, the bigger the change. When comparing preferred clothing color before the stay in Korea with after the stay in Korea, both before and after the stay in Korea had the highest preference for achromatic colors. The frequency of change was mostly from achromatic color to other colors. In the preferred clothing pattern, 'plain' was their favorite one before the stay in Korea, while it turned to 'nature pattern' after the stay in Korea, followed by 'plain' one. In the textiles, the most preferred one was 'cotton', before and after the stay in Korea. However, their preference for cotton was lower after their stay in Korea than before the stay in Korea, and instead there was more preference for 'silk', 'synthetic fiber', and 'other' sources.

• Journal of the Korea Convergence Society
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• v.9 no.5
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• pp.151-156
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• 2018

In this study, CFRP and metal or nonmetal were bonded with adhesive and the fracture study on this material was carried out. CFRP at the upper side of specimen and metal or nonmetal were assigned at the lower side of specimen by using DCB specimen as the analysis condition. And it was desribed that the structural adhesive were bonded between both upper and lower sides. As this analysis result, the least equivalent stress was shown at the specimen bonded with aluminium. The maximum shear stress was shown to become lowest at the de-bonded CFRP specimen when titanium was used. In conclusion, it was shown that the deformation of specimen became lowest when titanium was used. On the basis of this study result, the esthetic sense can be shown as the fracture data of bonded interface using adhesive are grafted onto the real life.

• Journal of Technologic Dentistry
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• v.38 no.1
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• pp.1-6
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• 2016

Purpose: The present study was to determine the stress distribution of an abutment screw according to implant abutment material. Methods: This study was a tightening torque 10 Ncm, 20 Ncm, set to 30 Ncm, and a titanium alloy (Ti-6Al-4V), PEEK (polyetheretherketone), Endoligns (60% Carbon Fiber Reinforced PEEK) material of the custom abutment titanium alloy (Ti-6Al-4V) the stress distribution in the material of the abutment screw will be evaluated by the finite element analysis. Results: Abutment screw most stress has been concentrated on the interface between the fixture and the abutment was also part of the interface that the threads are started. Depending on the abutment of the abutment screw Material von Mises stress values are shown differently. 10Ncm T10 under the tightening torque of 294.2 MPa, P10 is 562.8 MPa, appeared to E10 is 295.8 MPa, 20Ncm tightening torque under T20 is 581.1 MPa, P20 is 1125 MPa, E20 was shown to 585.1 MPa, 30Ncm tightening torque under T30 is 918.2 MPa, P30 is 1795 MPa, E30 has appeared 925.1 MPa. Conclusion: If the abutment is used as Endoligns, it was confirmed that the abutment screw exhibits of von Mises stress value is similar to the titanium alloy abutment.