• The Transactions of the Korean Institute of Power Electronics
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• v.26 no.2
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• pp.141-149
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• 2021

In the field of electric vehicles and AGVs, wireless power transfer (WPT) charging systems have been developed recently because of its convenience, reliability, and positive environmental impact due to cable and cord elimination. In this study, we propose a WPT charging system using a single stage AC-DC converter that can be reduced in size and weight and thus can ensure convenience. The proposed single-stage AC-DC converter can control a wide output voltage (36-54 VDC) within coupling ranges by using the variable link voltage applied to the WPT resonant circuit through phase-shifted modulation at a fixed switching frequency. Moreover, the input power factor and total harmonic distortion can be improved by using the proposed converter. A 1 kW prototype that can operate with an air gap range of 40-50 mm is fabricated and validated through experimental results and analysis.

• Journal of Veterinary Clinics
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• v.40 no.5
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• pp.330-335
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• 2023

Platelet function evaluation by PFA-100 or -200 has been known to be objective and sensitive for assessing platelet function and dysfunction of Von Willebrand Factor in humans and dogs. However, using the C/EPI cartridge in dogs is controversial. This study aimed to establish a reference range for PFA closure time in healthy small breed dogs (body weight < 10 kg) and to evaluate the effectiveness of both C/ADP and C/EPI cartridges for these dogs. Citrated blood samples were collected from 50 clinically healthy small breed dogs that were admitted for presurgical procedures or health checkups, and closure times were measured using the PFA-200. Reference ranges were determined as 42-144 s (median 67 s, mean 71.2 s, SD ± 21.2 s, 95% RI 43-140 s) , for CT-C/ADP and 41-200 s (median 87, mean 91.2 s, SD ± 31.8 s, 95% RI 44-195 s) for CT-C/EPI. The present study demonstrated that the reference ranges for PFA closure times in small breed dogs are in line with existing reference ranges. The utilization of C/ADP cartridges is the preferred choice for evaluating platelet function in small breed dogs. However, due to variable responses of epinephrine to platelet aggregation in dogs, caution should be exercised when using C/EPI cartridges.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1330-1334
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• 2013

The purpose of this study was to analyze the association between self-reported voice problem and body mass index. Data were collected from the 5th Korea National Health and Nutritional Examination Survey (2010) from 5,811 subjects(2,503 men and 3,308 women) aged 19 years and olders. chi-square, t-test and multi-nominal logistic regression analysis were used that to compare self-reported voice problem and variable(age, sex, hight, weight, waist measurement, body mass index). body mass index(OR=1.028, 95% CI: 1.003-1.056) was independently associated with self-reported voice problem(p<0.031). also over weight-two step obesity (OR=1.765, 95% CI: 1.036-3.006) were independently associated with self-reported voice problem(p<0.036). The results of comparison verified that body mass index are valuable self-reported voice problem of risk factor. when the evaluation were conducted, what was considered body mass index is needed.

• Korean Journal of Health Education and Promotion
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• v.18 no.3
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• pp.11-36
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• 2001

The purpose of this study is to analyze health behavior by comparing the difference between self-perceived health status and health examination results. The study subjects consist of 7,702 people aged over 20, surveyed by Health Interview survey, Health Examination survey, Dietary Life survey, Health Consciousness and Behavior survey. Data used in the study are drawn from raw data from a 1998 National Health and Nutrition survey. General characteristics variables are sex, age, education level, residential area, marital status, occupation, and living standard while dichotomous variables, ‘not healthy’ and ‘healthy’ are used to measure self-perceived health status. Variables for health examination results are high blood pressure, high cholesterol, diabetes, liver diseases, liver inflammation, kidney diseases, normal weight, regular diet, optimum sleeping time(7-8 hours), regular health examination and health behavior practice group. Major findings of the study are as follows: 1) Analysis of self-perceived health status and health behavior by disease: Variables significantly correlated with high self-perceived health status have strong associations with high health behavior practice, which supports the hypothesis that as one has high self-perceived health status, one is more likely to practice health promoting behavior. The results of analysis of health behavior differences by dividing subjects into two categories, ‘cases of illness’ and ‘cases of no illness’ indicate that drinking, sleeping time, health examination are significant variables (p〈0.001, 0.05) whereas smoking, weight control, regular exercise, regular diet are not significant. 2) Analysis of disparity patterns between self-perceived health status and health examination: The hypothesis that health behaviors would be different according to the disparity pattern between self-perceived health status and health examination is supported as a result of χ2 test. Among Type I : Self-perceived health status is high and actual health status is good (no disease) Type II: Self-perceived health status is high and actual health status is poor(have disease) Type III: Self-perceived health status is low and actual health status is good(no disease) Type IN: Self-perceived health status is low and actual health status is poor(have disease) Type I and Type IV show no disparity, Type I shows the highest health promoting behavior whereas Type IV shows the lowest health promoting behavior. Type II, and III, compared to Type I, practise lower health promoting behavior. Multi-logistics regression analysis was conducted to find out the degree of impact on health behavior. Independent variables are general characteristics, self-perceived health status and health examination result and presence of illness, while the dependent variable is health promoting behavior. The analysis of the impact of self-perceived health status on the health promoting behavior shows that smoking, drinking, weight control, regular exercise, health examination practice, and/or regular diet are significantly correlated to self-perceived health status. High self-perceived health status is inversely related to high health promoting behavior. This finding supports the hypothesis that the higher one perceives one's health, the more likely one is to practice health promoting behavior. On the contrary, the presence of illness has little impact on health promoting behavior. 3) Multiple logistics analysis on how disparity patterns between self-perceived health status and health examination affect health behavior: The results of multiple logistics analysis made on health behavior variables compared to the standard variable are as follows: When analyzed on the standard of Type I, smoking is a significant risk factor for the Type IV. In case of drinking, all the patterns show a high probability of relative risk ratio. With regard to weight control, it is a risk factor for Type II while all the patterns show high probability of not practising when analyzed on the standard of type IV. Type III and IV show high probability of not doing regular exercise while Type IV, shows a high probability of not taking appropriate sleeping time. When analyzed on the standard of type IV, all the patterns show a high probability of not taking health examinations. Type III and IV show a high probability of not having regular meals. As for overall health promoting behavior, Type III and IV show a high relative risk ratio. These two groups have low self-perceived health status. It implies that self-perceived health status has significant impact on health promoting behavior. This is also supported by the fact that Type I with high self-perceived health status and no illness shows a high practice rate of health promoting behavior. Types II and III the groups with high disparity between self-perceived health status and health examination results, show a low practice rate of health promoting behavior when compared to Type I. Type IV, that is the group with low self-perceived health status and actual illness, shows the lowest practice of health promoting behavior. It is highly probable that this type proves to be the poorest health group.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.9_10 s.146
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• pp.1219-1229
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• 2005

The objectives of this study were to investigate the differences in clothing and body attitude according to demographic variables, and to examine how clothing and body attitude were influenced by social values and demographic variable of adolescents. The questions of 5-point Likert scale were used for the evaluation of clothing attitude, body attitude, and social values. Four dimensions of social values were derived by factor analysis: 'the sense of estrangement', 'the satisfaction with school life', 'materialism', and' the sense of community'. Subjects were 373 adolescent girls in Seoul(182 middle school students and 191 high school students). The data were analyzed by using factor analysis, t-test, one-way ANOVA, and multiple regression analysis. First, the conformity to entertainers' dresses was influenced by materialism and age(-). Clothing aesthetics was influenced by materialism and allowance, and fashion was influenced by materialism. Second, the interest of plastic surgery was influenced by materialism and allowance. The interest of weight was influenced by the sense of estrangement, school grade(-), the education level of mother, materialism, and the satisfaction with school life. The interest of makeup was influenced by allowance, school grade(-), and the education level of mother(-). Appearance satisfaction was influenced by the sense of estrangement(-) and the satisfaction with school life. The present result means that social values such as materialism and the sense of estrangement are significant variables to understand the appearance attitude of adolescents.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1641-1649
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• 2014

This study aimed to analyze the occurrence of colon polyps and also risk factors of colon polyps. Among health examination examinees, 508 people were included who underwent colonoscopy and abdominal ultrasonography at the same time. Physical measurements also performed such as height, weight, blood pressure, waist measurement and BMI. General characteristics including age, sex, smoking, drinking and exercise as a risk factors were checked. At the same time, we analyzed various blood tests and fasting blood sugar through blood-gathering. In the results, regarding risk factors of colon polyps, AST, ALT, TC, fatty liver, obesity and smoking were shown significantly high. As a dependent variable with colon polyps, the highest relation was fatty liver(3.4 times), and then T-C(2.3 times). Smoking factor showed 2.3 times higher relation than non-smokers.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.4 s.74
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• pp.357-367
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• 2006

Drift design methods using resizing algorithms have been presented as a practical drift design method since the resizing algorithms proposed easily find drift contribution of each member, called member displacement participation factor, to lateral drift to be designed without calculation of sensitivity coefficient or re-analysis. Weight of material to be redistributed for minimization of the lateral drift is determined according to the member displacement participation factors. However, resizing algorithms based on energy theorem must consider loading conditions because they have different displacement contribution according to different loading conditions. Furthermore, to improve practicality of resizing algorithms, structural member grouping is required in application of resizing algorithms to drift control of high-rise buildings. In this study, three resizing algorithms on considering load condition and structural member grouping are developed and applied to drift design of a 20-story steel-frame shear-wall structure and a 50-story frame shear-wall system with outriggers.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.550-555
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• 2001

Insulin-like growth factor-I (IGF-I) is a mitogenic peptide with a molecular mass of 7 kDa. It is produced mainly in the liver and has important functions in the regulation of development and somatic growth. Moreover, Serum IGF-I concentration is regulated by the quantity and the nutritional quality of dietary protein. To determine the IGF-I level in Korean rockfish, Sabastes schlegeli, were fed four experiment diets that contained different protein quantities, namely $30\%,\;40\%,\;50\%\;and\;60\%$ for 70 days. Weight gain of the fish increased depending dietary protein quantity, Also, IGF-I concentrations increased according to dietary protein quantity, Feeding experiments were conducted to examine the effects of dietary protein sources on the serum IGF-I level in Korean rockfish, Fish meal (CO), soybean meal (SM), corn-gluten meal (CGM), meat meal (MM) and feather meal (FM) were used as variable protein sources of the formulated diet. IGF-I concentrations of the CO and MM groups ($277.7\pm23.2,\;291.5\pm41.2\;ng/mL$) were higher than those of the CGM and FM groups ($208.9\pm21.3,\;217.2\pm38.2\;ng/mL$). And IGFBP-3 levels by western blot analysis increased in good protein diets such as in the CO and MM groups. In conclusion, IGF-I may be a sensitive indicator the protein metabolism in fish as well as mammalian.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.1
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• pp.1-14
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• 2021

Onions are a representative produce that requires supply-demand control measures due to large fluctuations in production and price by growing season. Accurate forecasts of crop production can improve the effectiveness of such measures. However, it is challenging to obtain accurate estimates of crop productivity for onions because they are mainly grown on the open fields. The objective of this study was to perform the empirical analysis of the relationship between factors for crop growth and meteorological conditions, which can support the development of models to predict crop growth and production. The growth survey data were collected from open fields. The survey data included the weight of above ground organs as well as that of the bulbs. The estimates of meteorological data were also compiled for the given fields. Correlation analysis between these factors was performed. The random forest was also used to compare the importance of the meteorological factors by the growth stage. Our results indicated that insolation in early March had a positive effect on the growth of the above-ground. There was a negative correlation between precipitation and the growth of the above-ground at the end of March although it has been suggested that drought can deter the growth of onion. The negative effects of precipitation and daylight hours on the growth of the above-ground and under-ground were significant during the harvest period. These meteorological factors identified by growth stage can be used to develop models for onion growth and production forecast.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1994.10a
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• pp.49-58
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• 1994

The methods of estimation of VTS effectivenss are compared and the worldwide literature related to the VTS effectiveness is reviewed. The review suggests three potential approaches ; simulation ; synthesis of expert opinion and statistical analysis of casualties. this study adopted dissimilar approaches to estimate the VTS effectiveness to the earlier studies ; the combination of synthesis of expert opinion and causal analysis of casualty. The VTS effectiveness is derived by multiplying casualty rate reduction factors by the effect level of causal factors. The development of casualty rate reduction factors was based on the questionnaire survey and the evolution of effect levels was based on the causal analysis using functional block diagram. According to these procedures the maximum benefit to be obtained through the introduction of a VTS system was approximately 46 percent overall. The collision reduction rate was estimated to be approximately 50 percent for a VTS system with advanced radar surveillance. And 47 percent of groundings 36 percent of rammings and 21 percent of founderings could be reduced by the introduction of VTS. These figures are more or less the same to the earlier studies. The VTS effectiveness by the different causal factor groups was examined. VTS may reduce about 68 percent of causal factors classified as environmental conditions 40 percent of human factors and 35 percent of technical factors in collision accidents. As a whole 60 percent of environmental factors 41 percent of human factors and 20 percent of technical factors may be prevented by a VTS. The key variable of the effectiveness percentage is the value of weight coefficient $\delta$. Therefore differing values for this input was discussed and the impact that these variations have on the VS effectiveness noted. As the results of sensitivity analysis of VTS effectiveness by $\pm$10 percent the effectiveness is varied approximately three to seven percent by casualty type. And the value is changed roughly four to eight percent by a $\pm$10 percent variation by different sub-areas.