• Korean Journal of Human Ecology
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• v.4 no.2
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• pp.84-93
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• 2001

This study was to evaluate the effect of dietary taurine on bone mass loss in ovariectomized rats. Forty Sprauge-Dawly female rats (body weight 200$\pm$22 ) were divided into four groups. Control (sham) group was fed without taurine and the other three ovariectomized groups were fed the diets with 0%, 1% and 2% taurine for eight weeks. There was no significant difference in Plasma taurine level among the three ovariectomized groups. The sham group showed higher calcium level in femur than that of the other ovariectomized groups. There was no significant difference in phosphorus level in femur among the four groups. The levels of magnesium and zinc in sham group was higher than those of in the ovariectomized groups. The sham and 1% taurine fed ovariectomized group showed higher level of sodium than 0% and 2% taurine fed ovariectomized groups. Body weight and diet intake in sham group were lower than those of in the three ovariectomized groups due to ovariectomy. Breaking force and specific gravity of femur were not different significantly among the four groups. The level of minerals in l% taurine fed ovariectomized group was higher than that of in 0% taurine fed ovariectomized group even though the level of minerals in ovariectomized was lower than In sham group, which indicates that taurine supplementation might have benificial effects on osteoporosis.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.1
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• pp.1-8
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• 2014

This paper proposes an emotion classifier from EEG signals based on Bayes' theorem and a machine learning using a perceptron convergence algorithm. The emotions are represented on the valence and arousal dimensions. The fast Fourier transform spectrum analysis is used to extract features from the EEG signals. To verify the proposed method, we use an open database for emotion analysis using physiological signal (DEAP) and compare it with C-SVC which is one of the support vector machines. An emotion is defined as two-level class and three-level class in both valence and arousal dimensions. For the two-level class case, the accuracy of the valence and arousal estimation is 67% and 66%, respectively. For the three-level class case, the accuracy is 53% and 51%, respectively. Compared with the best case of the C-SVC, the proposed classifier gave 4% and 8% more accurate estimations of valence and arousal for the two-level class. In estimation of three-level class, the proposed method showed a similar performance to the best case of the C-SVC.

• Journal of Fashion Business
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• v.25 no.4
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• pp.79-91
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• 2021

Currently, chatbot, a conversational platform based on artificial intelligence, is drawing attention as a new marketing channel. This study attempted to verify the effect of the anthropomorphism, message type, and media self-efficacy level on purchase intention. The experimental design of this study was a 2 (anthropomorphism level of shopping chatbot: low vs. high) × 2 (message type: factual vs. evaluative) × 2 (media self-efficacy: low vs. high) three-way mixed analysis of variance (ANOVA). This study conducted a survey by the convenience sampling method of 402 women in their 20s and 30s living in Seoul and the Gyeonggi area who were aware of chatbot services. For the final analysis, 388 questionnaires were used. Data were analyzed with the SPSS 23 program and three-way ANOVA. Simple main effects analysis was conducted. The results of this study were as follows. First, there were statistically significant differences in purchase intention according to anthropomorphism level, message type, and media self-efficacy. Second, message type and media self-efficacy showed statistically significant interaction effects on purchase intention. Lastly, anthropomorphism and the media self-efficacy level and the message type of the shopping chatbots showed significant three-way interaction effects on purchase intention.

• Proceedings of the KIPE Conference
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• 2016.11a
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• pp.155-156
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• 2016

• Bulletin of the Korean Mathematical Society
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• v.58 no.3
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• pp.593-602
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• 2021

We use a kind of modified Hurwitz class numbers to express the number of representing a positive integer by some ternary quadratic forms such as the sum of three squares, and the Fourier coefficients of weight 2 modular forms of prime level with trivial character.

• Journal of Power Electronics
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• v.5 no.3
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• pp.224-232
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• 2005

A new three phase three-level Pulse Width Modulation (PWM) Switched Voltage Source (SVS) inverter with zero neutral point potential is proposed. It consists of three single-phase inverter modules. Each module is composed of a switched voltage source and inverter switches. The major advantage is that the peak value of the phase output voltage is twice as high as that of a conventional neutral-point-clamped (NPC) PWM inverter. Thus, the proposed inverter is suitable for applications with low voltage sources such as batteries, fuel cells, or solar cells. Furthermore, three-level waveforms of the proposed inverter can be achieved without the switch voltage imbalance problem. Since the average neutral point potential of the proposed inverter is zero, a common ground between the input stage and the output stage is possible. Therefore, it can be applied to a transformer-less Power Conditioning System (PCS). The proposed inverter is verified by a PSpice simulation and experimental results based on a laboratory prototype.

• Journal of Nutrition and Health
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• v.34 no.3
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• pp.330-337
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• 2001

The purpose of this study was to investigate the nutritional status of antioxidant vitamins in relation to serum malondialdehye(MDA) level in postmenopausal women with common occurance of cardiovascular disease(CVD). Data about general characteristics including smoking, drinking and exercise status, dietary intake and serum level of antioxidant vitamins, and serum MDA level were collected from eighty-five postmenopausal women. Mean serum MDA level was 1.62$\pm$0.03nmol/ml, and general characteristics and serum lipid profiles were not significantly different among the three group: low MDA(<1.45nmol/ml), midium MDA(1.45-1.74nmol/ml) and high MDA($\geq$1.74nmol/ml). Total mean vitamin A intake was 472.8$\pm$37.7RE, 68% of RDA, vitamin C intake was 134.3$\pm$8.7mg, 192% of RDA and vitamin E intake was 8.6$\pm$0.5mg, 86% of RDA for Korean. In takes of antioxidant vitamins from the diet were not significantly different among the three groups. However significant negative correlation(r=-0.242, p<0.05) was observed between vitamin E intake and serum MDA level in total subjects. Total mean serum vitamin A, $\beta$-carotene and vitamin C level were 0.59$\pm$0.01$\mu\textrm{g}$/ml, 0.25$\pm$0.01$\mu\textrm{g}$/ml and 9.02$\pm$0.28$\mu\textrm{g}$/ml, respectively. Total mean serum vitamin E and vitamin E/total cholesterol level were 9.15$\pm$0.42$\mu\textrm{g}$/ml and 4.09$\pm$0.17$\mu\textrm{g}$/mg, respectively. Serum antioxidant vitamins levels were not significantly different among the three groups. However serum vitamin C and E level were negatively correlated to serum MDA level. We can conclude that it will be helpful for postmenopausal women with common occurance of CVD to improve nutritional status of antioxidant vitamins by increasing intakes of antioxidant vitamins, especially vitamin C and E. (Korean J Nutrition 34(3) : 330~337, 2001)

• Journal of the Korean Data and Information Science Society
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• v.26 no.1
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• pp.281-288
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• 2015

In this paper, the maximum likelihood estimators and confidence intervals for parameters of Weibull distribution are derived under three level constant stress accelerated life tests and the assumption that a log quadratic relationship exits between stress and the scale parameter ${\theta}$. The compound linear plan proposed by Kim (2006) is used to allocate the test units at each stress level, which performed nearly as good as the optimum quadratic plan and had the advantage of simplicity. Some simulation studies are given.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.299-301
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• 1995

This paper represents an overvoltage clamping circuit for three level inverters. With a proposed overvoltage clamping circuit, the problems that high voltage stresses and voltage unbalance between outer and inner switches occurs in high power and high voltage 3-level inverters are reduced.

• Proceedings of the KSR Conference
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• 2003.10c
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• pp.646-652
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• 2003

AS a main Power Supply of the Railroad Vehicles, a three-Level ZVZCS DC/DC Converter is proposed in this paper. The proposed three-Level DC/DC Converter achieves zero voltage and zero current switching for the main switches. Its attribute is that the voltage across the switches is half the value of the input voltage. Also. using a diode and secondary side of the transformer, and simple auxiliary circuits it achieves zero current switching of the auxiliary switches. The principle operation and simulation results are included.