• Journal of Power Electronics
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• v.19 no.2
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• pp.560-568
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• 2019

This paper studies the inherent relationship between currents and zero-sequence components. Then a precise algorithm is proposed to calculate the injected zero-sequence component to control the DC-Link neutral-point voltage balance, which can result in a more efficient and flexible neutral point voltage balance with a desirable performance. In addition, it is shown that carried-based PWM with the calculated zero-sequence component scheme can be equivalent to space-vector pulse-width modulation (SVPWM). Based on the proposed method, the optimal zero-sequence component of the feasible modulation indices is analyzed. In addition, the unbalanced load limitation of the DC-Link neutral-point voltage balance control is also revealed. Simulation and experimental results are shown to verify the validity and practicality of the proposed algorithm.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1556-1560
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• 2012

A simple highly versatile and efficient method has been developed for the three-component coupling of aldehydes, amines and alkynes to prepare propargylamines, in the presence of a catalytic amount of $BiCl_3$. The advantages of methods are high yield, mild reaction conditions, no environmental pollution and easy work up procedure.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2203-2206
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• 2011

A mild and efficient procedure has been developed for the one-pot, three-component reaction of aldehydes, benzyl carbamate and allyltrimethylsilane in the presence of 3 mol % of magnesium bistrifluoromethanesulfonimide at room temperature to afford the corresponding protected homoallylic amines in high yields.

• Journal of the Korean Data and Information Science Society
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• v.15 no.4
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• pp.817-823
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• 2004

This paper describes a three dimensional motion recognition algorithm and a system which adopts the algorithm for non-contact human-computer interaction. From sequence of stereos images, five feature regions are extracted with simple color segmentation algorithm and then those are used for three dimensional locus calculation precess. However, the result is not so stable, noisy, that we introduce principal component analysis method to get more robust motion recognition results. This method can overcome the weakness of conventional algorithms since it directly uses three dimensional information motion recognition.

• Journal of the Korean Society of Safety
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• v.14 no.3
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• pp.120-126
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• 1999

This study was accomplished by measuring the lower and upper flash point with air blowing method and grasping the characteristics of flammability for the three component systems, which are made up of the Benzene-Toluene-o-Xylene and Methylethylketone-Toluene-o-Xylene. These three component systems are widely used in the various industrial fields together with the development of industry. The results are as follows ; 1 ) Isothermal line is plotted on the triangular diagram for flash points determined in each solutions. From this line, the mixed compositions which indicated the same lower and upper flash points in each different composition could be read on this diagram, if the composition of mixtures are known. 2) Lower and upper explosion limits obtained from the flash points determined for the three component solution are compared with the value calculated from Le Chatelier's law. Especially the lower explosion limits are in a good agreement with the calculated values.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.237-242
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• 2003

The object of this study is to investigate the strength development properties and the strength prediction of three-component concrete using the fly ash and the blast-furnace slag by a maturity method. The results were as follows. The values of the activation energy on this experiment are calculated as 38.69, 36.47, 32.46, 30.99 KJ/mol in the W/B 60, 55, 50, 45%. And it is considered that the equivalent age can be used to predict strength of the three-component concrete in the optional age. Also the strength of the three-component concrete can be predicted from the result of high correlation between predicted strength and measured strength.

• Analytical Science and Technology
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• v.32 no.4
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• pp.131-138
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• 2019

This paper reports results on the physical properties of a powder type of $Al_2O_3:C$ commonly used as a luminescence dosimeter using the LM-OSL technique. On the analysis with the general order kinetics model, the LM-OSL signal measured appeared to be composed of three components (fast, medium, slow) showing the largest area in the medium component. The photoionization cross sections of three components were distributed between $10^{-19}{\sim}10^{-21}cm^2$. The values of the thermal assistance energy were evaluated the largest in slow component and the smallest in fast component, which indicates the electrons trapped in defects attributed to slow component should be the most sensitive to thermal vibration among three components. In illumination to blue light, the fast component showed a rapid linear decay and completely disappeared after light exposure time of about 5 s. The medium component decayed with two exponential elements but the slow component did not observed any noticeable change until light exposure time of 40 s. In a dose response study, all components exhibited a linear behaviour up to approximately 10 Gy.

• Journal of the Korean Home Economics Association
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• v.35 no.1
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• pp.47-58
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• 1997

The purpose of this study was to investigate the relationship between children's gender role attitude measured by component model and social competency. Subjects were 232 elementary school children: 113 4th graders and 119 6th graders. The main results were as follows. First there were significant differences in mean scores of gender role attitude with age and sex variable. And among three dimensions of component model(i.e, gender label-component links within-component links between-component links) the difference was most discriminant in gender label-component links. Second there were significant relationship between gender role attitude and social competency. Among three dimensions of gender role attitude the most predictor variable for social competency was gender label-component links. And among four dimensions of social competency the most effective criterion variable for gender role attitude was leadership. And there were significant differences in social competency score with mother's educational level and sex of children as well as gender role attitude. In conclusion children's gender role attitude influence their social competency. More flexible gender role attitude they have more improved in their social competency , especially in boys.

• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.3 s.35
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• pp.208-215
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• 1990

The purpose of this study is to provide the fundamental data of a dummy design for more suitable ready made clothing by making a pattern of somatic types and analyzing their morphological characteristics in accordance with different pattern of somatic types. The side view silhouettes of 90 junior high school girls of age $13\~16$ in seoul urban area were measured by means of the plan photographing and the low data were examined by principal component analysis, while the principal component analysis was applied and three components were extracted and then interpreted to explain to variation of the form of the body. Using three components respectively the cluster analysis was carried out and the subject classified into 4 cluster The following outcomes are obtained. . The results of principal component analysis of this study would be turned out the three; 1) The first principal component shows the degree of erectness or stoop of the figure. 2) The second principal component was a stature length or a growth rate. 3) The third principal component was the obesity component. 2. The results of cluster analysis by using three principal component analysis would be turned out the four cluser; 1) Cluster 1 ($29\%$ of the total) is characterized with lower stature. 2) Cluster 2 ($21\%$ of the total) is characterized with backward somatotype, and the highest leg. 3) Cluster 3 ($23\%$ of the total) is thicked back of neck. 4) Cluster 4 ($27\%$ of the total) is characterized with forward somatotype, and highest stature, height.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.11 no.18
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• pp.35-39
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• 1988

In general, the characteristics of components which consist of multi component system can not be the same. This paper proposes a maintenance model of multi-component system according to the characteristics of each component. In this paper multi-component system is divided into three components-critical component, major component and minor component, respectively. Then we determine the optimal age replacement time of the system which minimizes total maintenance cost. Numerical examples are shown to illustrate the result.