• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.4
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• pp.403-407
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• 2023

In this paper, in order to investigate the efficiency of solar power generation system operation, we have studied operation cases such as generation amount, utilization rate, and generation time, and the following conclusions were obtained. The amount of power generation in 2017 was 1,311.48 MWh, and the amount of power generation in 2018 was 1,226.03 MWh. In 2021, 1,184.28 MWh was generated, and 90.30% compared to 2017, and the amount of power generation decreased by 1.94% every year. The deterioration of photovoltaic modules could be seen as one cause of the decrease in power generation. 1,977.74 MWh was generated in the spring, and 1,621.77 MWh was generated in the summer. In addition, 1,478.87 MWh was generated in the fall, and 1,110.55 MWh was generated in the winter, showing a lot of power generation in the order of spring, summer, fall, and winter. From 2017 to 2022, the seasonal utilization rate, daily power generation time, and daily power generation were investigated, and it could be seen that the spring utilization rate varies from 19.29% to 16.99%. It could be seen that the daily generation time in winter decreased from 2.67 hours to 2.13 hours, and in spring it generated longer than spring from 4.63 hours to 4.08 hours. In addition, the daily power generation in winter also decreased from 2.67 MWh to 2.13 MWh, and in spring it decreased from 4.63 MWh to 4.08 MWh, but it could be seen that it is more than in winter.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.10
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• pp.901-909
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• 2012

This paper describes characteristics of solid-state $NaBH_4$ hydrogen generation and supply system for fuel cell UAV. Flow rate and pressure of the generated hydrogen were dramatically changed during $NaBH_4$ decomposition using acid. Hydrogen supply was stabilized by a self-pressurized reactor, and hydrogen stabilization method was introduced. For hydrogen generation in below zero-temperature, hydrochloric acid was diluted by propylene glycol-water mixtures. Solid-state $NaBH_4$hydrogen generation and supply system was designed. Basic operation experiments was performed to reveal the characteristics of this hydrogen generation system.

• Health Policy and Management
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• v.23 no.4
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• pp.376-386
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• 2013

Purpose: The purpose of study is to estimate the number of chronic disease patients and medical care expenditure at the time baby-boomers belong to 65 years old aging population, and compare with current 65 year-old aging population. Methods: Analysis method used an estimating formula devised by the researcher and estimated the number of chronic disease patients and medical care expenditure of each generation. Results: When comparing the estimated number of chronic diseases patients of each generation, 40.6% of the first generation, 76.4% of the second generation, 95.2% of third generation are expected to get chronic disease. When comparing each generation's total medical care expenditure, based on the estimated number of chronic diseases patients of each generation, the second generation( 1,206,251,224 thousand won) showed higher than other generation. This study compared the number of chronic disease patients and medical care expenditure between the second generation of the elderly and current elder generation. As a result, the second generation patients was higher than the fourth generation in high blood pressure, diabetes, psychological and behavioral disorder, and neurological diseases whereas the fourth generation is only high the number of patients in heart disease. As for total medical care expenditure, the second generation paid more in high blood pressure, psychological and behavioral disorder while the fourth generation in neurological disease and heart disease. Conclusion: It is desired that considering the number of chronic disease patients and medical care expenditure of baby boomers accounting for 14.6% of total population, in-depth follow-up study is carried out that inquires into what are issues with a current chronic disease management project, what business is needed in order to manage these issues, and how to fund to cover increasing medical care expenditure.

• Fashion & Textile Research Journal
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• v.24 no.1
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• pp.81-94
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• 2022

The purpose of this study is to analyze the trends of MZ generation's lifestyle-related research from 2010 to 2020. As a result of searching keywords such as MZ generation's and lifestyle using academic database search sites, a total of 218 cases were used as analysis data to conduct frequency and content analysis. First, research type was 74 dissertations(34.6%), 144 journals(65.4%). The study of MZ generation was relatively active in journals. Second, the current status of academic field was 85(39.7%) in the social field, followed by 66(30.8%) in the arts/physical education, 21(9.8%) in the complex studies, 16(7.5%) in education, 15(7.0%) in nature, 6(2.8%) in engineering, 4(1.9%) in humanities, 1(0.5%) in agriculture/marine. Third, the current status of MZ generation research topics is 54 social participations(25.3%), 35 fashion/beauty(16.3%), 31 social/organizational adaptations(14.5%), 25 cultural/leisure activities(11.7%), 24 design/development projects(11.2%), 21 economic/employment/job projects(9.8%), 11 educational/career/experiences(5.1%), 9 self-concepts(4.2%), 4 welfare services(1.9%). Fourth, the current status of MZ generation research methods was quantitative research(survey/experiment) 125(58.4%), qualitative research(depth interview/participant observation) 42(19.6%), theory/literature research 35(16.4%) and mixed research 12(5.6%). Fifth, the study on the lifestyle of the MZ generation was conducted in four cases, one in 2016, one in 2019, two in 2020. This study is meaningful in that it grasped the overall flow of data of information exchange that can share the research trends of the MZ generation and suggested the basic data on the direction of future research, the individual tendency, behavior, and lifestyle characteristics of the MZ generation.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.305-308
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• 2012

The box tree pyralid, Glyphodes perspectalis, was reared on an artificial diet based on dried powder of box tree leaves, Buxus microphylla var. koreana, and INSECTA F-II (Nihon Nosan Co., Ltd) at a ratio of 3:7 (w:w) and analyzed in their developmental characteristics from $1^{st}$ to $4^{th}$ generation. The developmental period of larva reared on artificial diet was longer than that of larva reared on host plant. Significant difference in larval period was also observed between $1^{st}$ and other generation groups. Pupation rate was the highest in $4^{th}$ generation followed by $3^{rd}$, $2^{nd}$, $1^{st}$ and host plant group. Significant difference in pupal period was noted between $1^{st}$ and 3rd generation group. Emergence rate was the highest in $4^{th}$ generation group followed by $3^{rd}$, host plant, $1^{st}$ and $2^{nd}$ generation group. There is a significant difference in male and female size between $1^{st}$ and $4^{th}$ generation group. Our result indicated that stable rearing of box tree pyralid through the year is possible by artificial diet, and the best adaptation to artificial diet was achieved at $4^{th}$ generation.

• KIEE International Transactions on Power Engineering
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• v.4A no.4
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• pp.201-206
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• 2004

With the advent of distributed generation, power systems in general are impacted in regards to stability and power quality. Distributed generation has positive impacts on system restoration following a fault, higher reliability, and mitigation of effect due to voltage sag. However, distributed generation also has negative impacts on the decrease of reliability such as changes of protective device setting and mal-operation. Because bulk power systems consist of various sources and loads, it is complicated to analyze power systems that have distributed generation. The types of distributed generation usually are classified as the rotating machinery system and the inverter-based system. In this paper, distributed generation is designed as a synchronous generator, and the distribution system with its distributed generation model is simulated using EMTP. In addition, this paper shows the simulation results according to the types of distributed generation

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.4
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• pp.305-312
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• 2014

This paper discusses real-time peak shaving algorithms for a large-scale battery energy storage system (BESS). Although several transmission and distribution functions could be implemented for diverse purposes in BESS applications, this paper focuses on a real-time peak shaving algorithm for an energy time shift, considering wind power generation. In a high wind penetration environment, the effective load levels obtained by subtracting the wind generation from the load time series at each long-term cycle time unit are needed for efficient peak shaving. However, errors can exist in the forecast load and wind generation levels, and the real-time peak shaving operation might require a method for wind generation that includes comparatively large forecasting errors. To effectively deal with the errors of wind generation forecasting, this paper proposes a real-time peak shaving algorithm for threshold value-based peak shaving that considers fuzzy wind power generation.

• Korean Journal of Child Studies
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• v.32 no.4
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• pp.63-81
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• 2011

The purpose of this study was to examine the first generation Korean-American mothers' attachment representation as well as the attachment representation of their second generation Korean-American college students. The subjects consisted of 25 first generation Korean-American mothers and 27 second generation college students residing in Los Angeles. The Adult Attachment Interview (George, Kaplan, & Main, 1985) was used for assessing attachment representation patterns. The results of this study were as follows. First, 36% of the subject mothers were classified as secure, 64% were insecurely attached and there was no unresolved/disorganized pattern in the insecure group. Second, 33% of the subject students were classified as secure. 67% were insecure on the AAI, and there was 4% unresolved/disorganized patterns in the insecure group. Third, a difference of 76% was found between the correspondence between the first generation Korean-American mothers' attachment representation pattern and the attachment representation of the second generation Korean-American college students.

• Current Optics and Photonics
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• v.1 no.2
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• pp.138-142
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• 2017

Terahertz (THz) generation by periodically-poled $KTiOPO_4$ (PPKTP) with a quasi-phase-matching scheme based on cascaded difference frequency generation (DFG) processes is theoretically analyzed. The cascaded Stokes interaction processes and the cascaded anti-Stokes interaction processes are investigated from coupled wave equations. THz intensities and quantum conversion efficiency are calculated. Compared with non-cascaded DFG processes, THz intensities from 10-order cascaded DFG processes are increased to 5.53. The quantum conversion efficiency of 479.4% in cascaded processes, which exceeds the Manley-Rowe limit, can be realized.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.5
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• pp.383-389
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• 2010

Co-B, Co-P-B, Co-Ni-B and Co-Ni-P-B catalysts supported on Ni foam were prepared using electroless plating in the present study. The surface morphology of the catalysts/Ni foam was observed using SEM and EDS analysis. The Co-Ni-P-B/Ni foam catalyst showed the superior performance on hydrogen generation due to the uniform formation of catalyst particles on the Ni foam surface. The characteristics of hydrogen generation with Co-Ni-P-B/Ni foam catalyst was investigated at the variety of $NaBH_4$ and NaOH concentrations. Durability test was performed, resulting in the stable hydrogen generation for 6 hours.