• Journal of the Korea Convergence Society
• /
• v.2 no.4
• /
• pp.29-37
• /
• 2011

Dispersed generation (DG) such as wind power (WP) and Photovoltaic systems (PV) that has been promoted at the national level recently is mainly being introduced into distribution systems adjacent to consumers because it is generation on a small scale when compared to current generation. Due to its characteristics, DG can be operated by interconnection with distribution systems to present security of more stable power and efficient use of power facilities and resources. Problems on protection coordination of distribution systems by reverse flow of DG can roughly be divided into three possibilities: excess in rated breaking capacity (12.5KA) of protective devices by a fault in DG current supply, failure to operate protective devices by an apparent effect that can occur by reduction in impedance parallel circuit fault current due to interconnection of DG, and malfunction of protective devices by interconnection transformer connection type. The purpose of this study is to analyze problems in protection coordination that can occur when DG is operated by interconnection with distribution systems by conducting modeling and simulations by using theoretical symmetrical components and MATLAB/SIMULINK to present methods to improve such problems.

• Korean Security Journal
• /
• no.12
• /
• pp.73-87
• /
• 2006

This research is for examining the effect on personal health and differences between men and women by health care program in security guards and students, who are specializing security in college, appealing consciousness state physically and mentally. The following results are attained by conducting a questionnaire survey(T.H.I) of 358 men engaged in security guard services and 220 students specializing security (The data analysis is operated by Analysis of Variance(ANOVA) to make a comparative study of health care program, sex distinction and security careers. The implication of the study are as follows. 1. Generally students show less average rate than security guards in appealing the consciousness state especially in Mental Irritability, Irregular Life, Depression, Respiratory, Eyes and Skin, Aggressiveness. 2. In comparing men with women of consciousness state after the step of health care program, men show lower average rate than women except Life Scale and Respiratory. 3. In differences of consciousness state by security career, the more respondents have careers, the less the average rate of Mental Irritability and Depresaion is. But in Life Scale, the result is reverse.

• The Journal of Korean Academy of Sensory Integration
• /
• v.17 no.2
• /
• pp.41-55
• /
• 2019

Objective : This study was conducted to validate the content validity of the Korean version of the school setting interview (SSI) that assesses the adequacy of school environments for students aged 9-19. Methods : The Korean version of the SSI, which was completed via a translation-reverse translation process, was verified by conducting a questionnaire on category suitability two times with 35 experts. Results : The content validity index (CVI) for the entire K-SSI tool was .90 in the first test. The "Maps and diagrams" measurement in reading items and the "Taking a shower" measurement in sports activities were both below .75. A second round of verification was conducted after the CVI was modified. As a result, the secondary verification CVI results were further raised to .93. Conclusion : This study confirmed that the K-SSI contains items that are appropriate to Korean culture; it has been proven to have high content validity. Future continuous research and clinical use are required to study the validity and reliability of the K-SSI. Further, this tool should also be applied to students with diverse disabilities who face difficulties in school settings.