• Journal of Industrial Technology
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• v.23 no.A
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• pp.29-33
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• 2003

This paper proposed methods of filament preheating to extend a fluorescent lamp life. The ballast for the fluorescent lamp can be classified into two main groups magnetics and electronics. The electronic ballast is lighter and smaller than the magnetic ballast and it can dim up and down. There are two ways to start the fluorescent lamp in the electronic ballast: rapid start and instant start. Also there are two methods of the driving inverter self excited oscillation and force excited oscillation. The rapid starting is different from the instant starting in that the rapid start is preheating the filament before the steady state. If there is a preheating process before the lamp ignition, the life of the fluorescent lamp can be increased. This paper presented the preheating methods for self excited oscillating system and force excited oscillating system.

• The Korean Journal of Applied Statistics
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• v.34 no.1
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• pp.25-38
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• 2021

Recently the need for network surveillance to detect abnormal behavior within dynamic social networks has increased. We consider a dynamic version of the degree corrected stochastic block model (DCSBM) to simulate dynamic social networks and to monitor for a significant structural change in these networks. To apply a control charting procedure to network surveillance, in-control model parameters must be estimated from the Phase I data, that is from historical data. In network surveillance, however, there are many situations where sufficient relevant historical data are unavailable. In this paper we propose a self-starting Shewhart control charting procedure for detecting change in the dynamic networks. This procedure can be a very useful option when we have only a few initial samples for parameter estimation. Simulation results show that the proposed procedure has good in-control performance even when the number of initial samples is very small.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.682-684
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• 2015

A 12/14 bearingless switched reluctance motor (BLSRM) with hybrid stator poles has been proposed due to the outstanding decoupling characteristics between the torque and suspending force. However, the motor is a two-phase motor. The output torque of the motor has torque dead zone and high torque ripple. Hence, the motor cannot self-start at some rotor positions. To solve the self-starting problems and reduce the torque ripple, a stepped rotor is proposed in this paper. Then, the motor with the stepped rotor is optimally designed. In the new designed motor, the majority parameters are kept the same with those of original motor; only the torque pole arc and rotor pole shape are optimally designed. The characteristics of the redesigned motor, such as inductance, torque and suspending force, are analyzed and compared with those in the original motor. Finally, the effectiveness of the proposed method is verified by the simulation results.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.767-772
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• 2003

The clay which transported into a pond under the high water content condition have no effective stress which develop from the starting point of sedimentation and self-weight consolidation. Since sedimentation and self-weight consolidation dependent on self-weight of solids is made progress over a long time, to accelerating it have many advantages in the economic view In this paper, sand spreading method which is one of sedimentation and self-weight consolidation acceleration method is studied through a series of experiments considering the mixing ratio of sand and clay. The test results show that the mixing ratio of clay and sand of 1:0.2 is the biggest rate of consolidation and the pouring at the end point of sedimentation considerably effects on consolidation rate.

• Korean Journal of Adult Nursing
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• v.20 no.1
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• pp.10-20
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• 2008

Purpose: The purpose of this study was to analyze the effects of professional self-concept and self-efficacy on job satisfaction and to identify the relationship among them in clinical nurses. Methods: The subjects were nurses who were working for three general hospitals in Seoul and Gangwon province for two month starting in July 2007. Three questionnaires were used. One was job satisfaction and the others were professional self-concept and self-efficacy. The data were analyzed by SPSS/PC ver 12.0. Results: The mean score of job satisfaction was 2.99 (range: 1-5). The mean score of professional self-concept and self-efficacy were 2.71(range: 1-4) and 3.49(range: 1-5), respectively. Differences of job satisfaction were significantly related to differences in age, marital status, level of education, clinical career, annual salary, and shift pattern. With respect to job satisfaction, the pearson correlation coefficients were .43 for professional self-concept and .29 for self-efficacy. The multiple regression revealed that the significant predictor of job satisfaction was professional self-concept. Conclusion: This study showed that a strong professional self-concept improves job satisfaction, so professional self-concept improvement programs should be developed to improve job satisfaction and to improve the quality of nursing.

• Journal of the Korean Ceramic Society
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• v.36 no.12
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• pp.1356-1363
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• 1999

Self-reinforced silicon carbide was prepared by hot pressing and the control of starting phases of raw materials and its microstructural characteristics was investigated. The specimens with self-reinforced microstructure were obtained from the compacts with mixed compositions of ${\alpha}$-and ${\beta}$-SiC powders. Self-reinforced microstructure which is composed of large dispersed grains with rod-like shape and matrix with small equiaxed grains was formed by the transformation to the ${\alpha}$-SiC with 4H polytype for ${\beta}$-SiC and anisotropic grain growth during the heat treatment. Of all speimens the values of volume fraction maximum length and aspect ratio for large grains with rode-like types were the highest at the specimen with 50 vol% ${\beta}$-SiC in the starting SiC powder and therefore this specimen showed the highest fracture toughness due to the crack deflection by rod-like grains during crack propagation.

• Journal of the Optical Society of Korea
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• v.1 no.1
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• pp.41-43
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• 1997

We report the operation of a self-adaptive vector phase conjugate laser (VPCL) oscillator which compensates intracavity polarization distortion and wavefront aberration simultaneously. The VPCL in Nd:YAG gain media produce an output with energy of 125mJ in a 20ns single-longitudinal-mode pulse at 10Hz, which is unaffected by intracavity polarization distortion.

• Journal of the Korea Society of Computer and Information
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• v.21 no.3
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• pp.123-128
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• 2016

This study aims to analyze the causal relation between identity and school adaptation of multicultural family children, starting from necessity of empirical research considering insufficient preceding research. To achieve the purpose of the research, this study implemented empirical analysis regarding the causal relation between factors of self-identity and school adaptation. As a result, factors of self-identity implies significant effect on school regulations, while factors of school adaptation partially have an effect on school class and relations with a teacher and friend. Based on the result of verification, this study emphasizes teachers' effort as well as comprehensive and practical development of an educational program to help children from multicultural family establish the right self-identity for settling into school life. Moreover, the limitation of this study and future research direction is presented.

• Korean Journal of Human Ecology
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• v.15 no.2
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• pp.239-249
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• 2006

The purpose of this research is to examine the relationship among religiosity, self-esteem, and life satisfaction of the elderly. The subjects of this study are 228 elders living in Busan and Gyeongnam areas, who have religions such as Christianity or Catholicism. The main results of this study are as follows: 1) Elders' health condition, starting age of religion, and social religious activity are revealed to be significant variables which influence their self-esteem. 2) Self-esteem, individual religious activity, and health condition are revealed to be significant variables which influence their life satisfaction.

• Journal of Family Resource Management and Policy Review
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• v.9 no.1
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• pp.41-58
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• 2005

The purpose of this study was to analyze the effect of the influencing factors on the continuity and the willingness of continuing self-employment. The sample of 321 was selected from self-employed workers living in Daegu. For data analysis, t-test, multiple regression, and logistic analysis were used. The major findings were as follows : 1. The sustaining period of self-employment were affected by gender, age, and educational attainment of self-employed workers, as well as the amount of starting capital, couple's partnership in business or not, and the type of industry in business. 2. Willingness to continue self-employment is more likely for those who without other income source, have positive vision with future economic prospects, have more satisfied with their self-employed work.