• International Journal of Contents
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• v.18 no.1
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• pp.76-84
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• 2022

Tidal power generation plays a critical role in reducing greenhouse gas emissions. It uses a tidal force generated by gravitational force between the moon, the earth, and the sun. The change of seawater height generates the tide-generating force, and the magnitude of the change is the tide level. The tide level change has the same period as the tide-generating force twice a day, every 29.5 days, every year, and every 18.6 years. Sihwa Lake Tidal Power Station is Korea's first tidal power plant that began commercial power generation in August 2011 and has been accumulating a large volume of data on electricity production, power generation sales, sluice displacement, and tide levels. The purpose of this paper was to analyze the impact of the inefficiency factors affecting production and the tidal level change on tidal power generation and their characteristics using Sihwa Lake Tidal Power's operational performance data. Throughout this paper we show that tidal power generating operation is accurately predicting the trends of magnitude of tidal force to be periodical for each day. determining the drop to initiate the water turbine generator factoring the constraints on the operation of Sihwa Lake, and reflecting the water discharge through the floodgate and water turbine during the standby mode in the power generation plan to be in the optimal condition until the initiation of the next power generation can maximize power generation.

• Korean Educational Research Journal
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• v.38 no.3
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• pp.189-210
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• 2018

This paper begins with the notion of 'pick-me generation', which refers to today's young generation in Korea. It is named after the title of a song introduced at the Television programme for the competitive audition for girl-group singers. This name gives an idea of the atmosphere of the competition that the current young generation experiences in South Korea. In parallel to it, the research examines the meaning of freedom and choice in democratic education in Oh Chunsuck, in his later work in particular. This paper attempts to demonstrate the possibility to relate Oh's notion of freedom and democracy in relation to Han who critically analyses contemporary discourses on neo-liberalism and democracy. This paper re-views Oh's ideals of democracy and education within its own limitations on freedom. The argument extends Oh's idea of freedom and ethical democracy to the idea of freedom that is relevant to today's younger generation.

• Journal of Fashion Business
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• v.12 no.2
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• pp.28-41
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• 2008

Fashion style in movies delivers their image the atmosphere and becomes the means for containing the personality, spiritual world and inner thinking the characters in the movies and including its plot. When the American new cinema emerged in late 1960's and early 1970's in the American movie history, the new left wing which wants to overturn adult generation and the hippie culture which wants to escape from an existing system also emerged. Therefore, this study analyzed the fashion style in the movie 'Easy Rider (1969)', i.e. the representative new American movie which showed the isolation from adult generation and negative realities of the American society. From the movie, we can understand the young generation after the Vietnam war, i.e. baby boom generation, pursued the hippie culture as their young culture. With their strong self-consciousness, they formed their own lifestyle and values which are different from those of adult generation, and we can understand clothes were used as a tool to express their value system.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.35-38
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• 2008

Our country need to introduce wind force power generation system that country is small and narrow and becomes positioning with the other country because there are many mountainous regions. power generation efficiency of existent wind force power generation system is droping rapidly and connote much problem in country quality in case of a low wind. We proposed wind force power generation system that use oil pressure motor and synchronous motor that can improve choice of suitable suspension style and country quality in Korean methods special qualify to improve this.

• Journal of Korea Foundry Society
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• v.19 no.5
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• pp.427-432
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• 1999

Most investment castings contain some porosities and microcavities. In this study, we investigated the elimination trends of various internal defects in IN738LC investment castings for industrial gas turbine blade by hot isostatic pressing. The results showed that cylindrical defects which are under $0.6mm{\Phi}{\times}7mm$ size are mostly eliminated and aspect ratio of defects is more sensitive factor than their cross section shape in removing these defects. Increasing hot isostatic pressure and holding time doesn't affect the elimination trend of cylindrical defects over $0.6mm{\Phi}{\times}7mm$ size because first step(plastic deformation) of HIP densification doesn't occur under these HIPping conditions.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.6
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• pp.470-476
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• 2021

In the near future, with the urgent requirement of environmental protection, hydrogen based energy system is essential. However, at the present time, most of the hydrogen is produced by reforming, which still produces carbon dioxide. This study proposes a high-power electrolytic hydrogen production system based on solid oxide electrolysis cell with no harmful emissions to the environment. Besides that, the parametric study and optimization are also carried to examine the effect of individual parameter and their combination on system efficiency. The result shows that the increase in steam conversion rate and hydrogen molar fraction in incoming stream reduces system efficiency because of the fuel heater power increase. Besides, the higher Faraday efficiency does not always result a higher system efficiency.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.365-368
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• 2006

The objective of this research is to investigate usage of 3KW photovoltaic-wind power hybrid generation system composed of 500W solar power generator and 400W wind power generator in a parallel circuit. In addition, solar radiation meter and wind monitor have been installed into each generation system to obtain the practical operating data that monitored in monthly, daily and hourly. These data that are independent to weather change and location would provide adequate generation output on average and cope with emergency situation in generation system In conclusion, based on this study, it could be considered for 3KW combined generation system to be gradually propagated to houses and small-size public facilities.

• 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.

• Proceedings of the KIEE Conference
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• 1992.07a
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• pp.106-109
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• 1992

This paper Introduces the concept of the generation cost of generating utilities and its calculation methods. Also, the economic evaluation method using generation cost which is called as a screening curve method will be presented along with the benefits and disadvantages of this concept. Next, the least-cost electric utility planning techniques which is used very widely in many countries will be Introduced In comparison with screening curve method. In this aspects, the optimal dynamic mix can be determined as a result. By comparing these two concepts, we will get the concrete concept why the economic evaluation method using generation cost can not be used for the future generation expansion planning.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.11
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• pp.1571-1577
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• 2012

This paper presents a method for assessing the voltage sag performance of power system involving wind power generation. Wind power generation is considered as one of the most desirable renewable energy sources. However, wind power generation have uncertain energy output and it is difficult to control the output. The existing methods of voltage sag assessment are not reflected the characteristics of wind power generation. Therefore, in order to more accurately assess the voltage sag performance, the probability of wind power operation is evaluated. In this paper, the probability is determined by combining the wind speed model with the output curve of wind turbine. The probability of wind power operation is reflected as a parameter in voltage sag assessment. The proposed method can provide more accurate results of voltage sag assessment for the case involving the wind power generation.