• Journal of Institute of Control, Robotics and Systems
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• v.9 no.7
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• pp.556-562
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• 2003

This paper presents new attitude error differential equations to define attitude errors as the rotation vector for inertial navigation systems. Attitude errors are defined with the rotation vector between the reference coordinate frame and the platform coordinate frame, and Platform dynamics to the reference coordinate frame due to platform torque command errors are defined. Using these concepts for attitude error definition and platform dynamics, we have derived attitude error differential equations expressed in original nonlinear form for GINS and SDINS and showed that these are equivalent to attitude error differential equations expressed in known linear form. The relation between attitude errors defined by the rotation vector and attitude errors defined by quaternion is clearly presented as well.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.10
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• pp.843-848
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• 2001

Most of gimballed inertial navigation systems(GNIS) are calibrated periodically to maintain their inherent accuracy. The existing calibration techniques using the conventional schuler test with the least square method and the multiposition test take a long time and have some problems in procedures. To solve this problem, calibration method using a linear Kalman filter is proposed by us. In this paper, the calibration method by the change of Schuler period is studied in order to improve the calibration performance of the gimballed INS. First of all, it is shown that the observability of Kalman filter is also enhanced the Schuler period is decreased. Simulation results show that the calibration performance using the present scheme is improved according to the decrease of the Schuler period and the calibration time is shortened extremely, too. And our proposed technique shows desirable estimation performance for the g-sensitive errors of inertial sensors in particular.

• The Research Journal of the Costume Culture
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• v.13 no.4 s.57
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• pp.526-539
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• 2005

Recently in the apparel industry, early adolescent girls are emerging as a new consumer group. In response to this, companies are developing clothes, cosmetics, underwear, etc. This study proposed a new size range and size interval for early adolescent girls and presented reference measurements for body parts necessary in designing clothes. For this purpose, a total of 529 girls aged between 10 and 14 were measured and data were collected from 42 anthropometric measurements and 41 photographic measurements per a person. SAS 8.1 was used in data analysis including means, standard deviations, frequency analysis. Based on the results, this study proposed: for Type A - 7 sizes (140A-67, 145A-65, 145A-69, 150A-69, 150A-73, 155A-73, 155A-76): for Type X - 7 sizes (150x-72, 155x-72, 155x-77, 160x-77, 160x-80, 165x-77, 165x-80); and for Type H - 8 sizes (145H-74, 145H-82, 150H-78, 150H-82, 155H-82, 155H-86, 160H-86, 160H-88). Reference measurements suggested for upper garments were 9 items. The outcome of this study may be used as a basic material for adolescent apparel manufacturers to set their apparel sizing system and to supply their consumers, namely, adolescent girls with products fitting their somatotype.

• Journal of the Korean Ceramic Society
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• v.40 no.2
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• pp.178-183
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• 2003

Electrical conductivity of$50Li_2O-xTiO_2-(50-x)P_2O_5$ glasses has been studied with an increase of the intermediate$TiO_2$content. Thermal properties were observed from TG-DTA measurement and the variation of glass structure was investigated by FT-IR. The density and glass transition temperature increased with an increase of the $TiO_2$ content. These results were attributed to the fact that bond strengthening was occurred because of the formation of P-O-Ti cross linkages in the glass. The ionic conductivity increased with $TiO_2$ content and a maximum value, $1.2{imes}10^{-6}$S/cm showed at x=20. The ionic conductivity showed a large increasement as a result that the pyrophosphate group become the predominant structural unit. This result can explain that Li ions mobility increased as a number of non-bridging oxygen on phosphate units increased.

• Journal of Preventive Medicine and Public Health
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• v.33 no.1
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• pp.83-90
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• 2000

Objectives : To assess the prevalence rate of dyslipidemia and the level of related factors in adolescents groups in Seoul and Yangpyong area. Methods : Design; School based survey during May-Jun 1996 in Seoul and Yangpyong county. Subject; 2,453 boys and girls, aged 13 to 19 years; 1,137 Seoul and 1,316 Yangpyong county. Main Outcome Measures; Prevalence rates of raised serum total cholesterol, triglycerides, LDL-cholesterol, decreased HDL-cholesterol, obesity, and levels of energy intake and expenditure Results : Energy intake and fat intake of boys were higher than those of girls and they were higher in Seoul. Energy expenditure per day of boys was bigger than that of gins too. Prevalence rate of obesity was higher in boys of Seoul(15.2%) and girls in Yangpyong county(14.0%). Serum lipid profiles(total cholesterol, triglycerides, LDL-cholesterol) were higher among girls and all prevalence rates of dyslipidemia were higher in boys in Seoul and in girls in Yangpyong county. Especially, girls(29.1%) in Yangpyong had raised serum cholesterol level$(\geq170\;mg/dl)$. In contrast, boys in Seoul had higher level of decreased HDL-cholesterol(46.8%) compared to Yangpyong(23.6%). The relationships between serum lipid profiles and relative weights and sex are highly significant. And the relationship between triglycerides and energy intake is significant(p=0.038). But, the associations between serum lipid profiles and energy expenditure had borderline significances Conclusions : Hypercholesterolemia rates in girls were higher. Obesity prevalence rate was highest in boys of Seoul. Relative weight and sex are significantly related to lipid profiles. Therefore, Korea is in need of preventive strategies for different obesity and gender groups.

• Journal of Ginseng Research
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• v.22 no.2
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• pp.114-121
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• 1998

Osteoporosis is defined as a pathologic condition in which there occurs no change in the chemical composition of the bone, while bone resorption is abnormally increased. This compares with osteogenesis, which leads to a decrease in the amount of bone. Though many varieties of therapies have been tried, no fully effective method has been found. Korean red ginseng is an important variety of Korean ginsengs and many studies have been performed to investigate its effectiveness. But there has been no report on red ginseng's effects on osteoporosis. The purpose of this study was to determine the clinical effects of Korean red ginseng on postmenopausal osteoporosis patients. The study was designed as a double-blind study. Group I consisted of 30 postmenopausal osteoporosis patients who were administered red ginseng extracts and 15 patients who were administered maltose capsules, were included in group II. The following results were obtained after one-year administration to both groups. 1. There were no significant differences in the degree of wedging, number of compression fractures in the vertebral body, trabeculations, and Cobb's angles between the experimental and control groups. 2. Even though bone mineral density increased in the lumbar spine, and decreased in the femur, there was no significant statistical difference. 3. The serum levels of parathyroid hormone (PTH), calcium, phosphate, and alkaline phosphates showed no difference between the two groups regardless of treatment. 4. Urine Deoxy-pyridinoline (DPYD) decreased in the red ginseng group while it increased in the maltose group, but statistically there was no significant difference between the two groups. 5. The clinical presentations showed no significant differences using Visual Analog Scale. 6. The specific complications related with the long-term use of red ginseng did not occur in all patients. In conclusion, there were no statistically significant differences in clinical presentations, biochemical, and radiological studies between the red gins eng and maltose groups. No definite effectiveness of red ginseng on patients with osteoporosis was found.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.69-74
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• 2005

In Oriental medicine the primordial Qi and the defensive Qi are considered as important for immunity. Therefore it is anticipated that the improvement of the primordial Qi and the defensive Qi can enhance the ability of immune cells. This experiment was conducted to investigate how Ginseng Radix, Astragali Radix, Atractylodis Rhizoma Alba, Glycyrrhizae Radix, representative of Qi tonifying herbs, affect the immune system in terms of controlling and balancing immune cells. Using the MTS assay, increased proliferations were observed from herbal treated cells, among which Gins-eng showed the highest proliferation. When splenocytes were activated with anti-CD3 plus herbal extracts, levels of IFN-g and IL-4 were increased but those of IL-2 showed little change compared with the control cells. Levels of IL-2, IFN-g and IL-4 were increased in purified CD4 T cells when activated with anti-CD3/anti-CD28 but at $100\;{\mu}g/ml$ of Astragali and Atractylodis, levels of IL-2 were decreased by 11% and 42%, respectively and those of IFN-g were decreased by 55% and 12%, respectively. Under Th1/Th2 polarizing conditions, levels of IFN-g in Th1 cells treated with herbal extracts were all decreased but when it comes to IL-4, its levels were increased in Ginseng and Glycyrrhizae treated cells but decreased in Astragali and Atractylodis treated cells. Taken together, the data show that compared with other qi tonifying herbs, Ginseng and Glycyrrhizae have a tendency to favor Th2 cell differentiation in vitro.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.493-501
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• 2002

This study evaluated the microleakage performance of four self-etcing primer adhesives(Clearfil SE Bond, Clearfil Liner Bond 2, UniFil Bond, and FL Bond) and one self-etching adhesive(Prompt L-Pop). Class V cavity preparations with occlusal margins in enamel and gingival margins in dentin were prepared on both buccal and lingual surfaces of 50 extracted human molar teeth. Prepared teeth were randomly divided into five groups and restored using one of five adhesives and composite resins: Prompt L-Pop/Filtek Z 250(Group 1), Clearfil SE Bond/Clearfil AP-X(Group 2), Clearfil Liner Bond 2/Clearfil AP-X(Group 3), UniFil Bond/UniFil F(Group 4), and FL Bond/Filtek Z 250(Group 5). Following one day storage in room temperature water, the restored teeth were thermocycled for 500 cycles between 5$^{\circ}C$ and 55$^{\circ}C$. Marginal microleakage was assessed by dye penetration using 2% methylene blue dye. After 24 hours, the teeth were sectioned longitudinally and evaluated for microleakage under steromicroscope The data were statistically analysed by Kruskal-Wallis Test, Mann-Whitney and Wilcoxon signed ranked tests. The results of this study were as follows ; 1. The microleakges at both enamel and dentinal mal$.$gins were the lowest in group 4. increasing among groups in the following order: group 2, follwed by group 5, follwed by group 1, and the highest in group 3. 2. At the enamel margins, the microleakage of group 3 was significantly higher than those of groups 2. 4 and 5(p<0.05), and also the microleakage of group 1 was statistically higher than those of groups 2 and 5(p<0.05). 3. At the dentinal margins, microleakage of group 3 was signincantly higher than microleakages of groups 1, 2, 4 and 5(p<0.05). 4. Compared with microleakages between the enamel and dentinal margins of each group, groups 1, 4 and 5 at enamel margin and group 2 and group 3 at dentinal margin were higher microleakage. But there was no significant difference between enamel and dentinal microleakages of each group(p>0.05).