• Environmental and Resource Economics Review
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• v.27 no.4
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• pp.695-723
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• 2018

Recently, extreme weather due to climate change has become more frequent, and increase of fine dust has worsen air quality in Korea. Therefore, not only negative perception on coal-fired power generation is dominant, but also the social acceptance of nuclear power generation declines. This study aims at deriving consumer preferences on the mid and long term power mix with various energy sources. Willingness to pay for each generation source was estimated and the preference heterogeneity of consumers was examined by using mixed logit and latent class models. Mixed logit estimation results show that the preference heterogeneity of consumers is especially large for the nuclear power relative to renewable or coal energy. According to the estimation results from the latent class model, group 1 prefers renewable energy while group 2 prefers coal energy. Group 3 shows lexicographic preference which means restricted rationality. As for the policy implication, it is necessary to understand the preference heterogeneity of consumer groups in planning the mid to long term power mix.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.4
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• pp.708-717
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• 2009

Recently, Korea government decided to introduce RPS (Renewable Portfolio Standard) mechanism which requires electricity providers to gradually increase the amount of renewable energy sources such as wind, solar, bioenergy, and geothermal. As a consequence, it is expected that the long-term fuel mix would be changed to result in more expensive production and the increased production costs would be distributed to the rate payers via electricity tariffs. This paper presents the change in long-term fuel mix in year 2020 with the four RPS scenarios of 3%, 5%, 10% and 20%, and the methodologies for collecting the increased production costs through new tariff schedule. The studies on long-term fuel mix have been carried out with the GATE-PRO (Generation And Transmission Expansion Program) optimization package, a mixed-integer program developed by the Korea Energy Economics Institute and Hongik university. Three methodologies for distributing the production costs to the rate payers have also been demonstrated.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.97-102
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• 1997

In this study, a predictive method which was modified from KIshi's model for the temperature development of concrete was developed by using mineral compounds of clinker and pozzolans. Temperature dependent heat generation of reaction was also considered. Specific heat considering the effect of mix proportion and temperature was calculated with experimental data in the literatures. Thermal conductivity considering the effect of mix proportion and temperature was experimentally investigated. Through this research it was found that the developed method considering thermal properties accurately predicted adiabatic temperature rise of concrete without the experiment. It was also found that the thermal conductivity of concrete could be predicted by the volume ratio of each component of mix proportion and was independent of temperature within the normal climatic range.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.121-122
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• 2008

우리나라의 가장 큰 섬인 제주도는 육지계통과 연결된 직류연계선 및 제주도내 발전기를 이용하여 전력을 공급받고 있다. 정부와 우리 한전은 제주도의 지속적인 전력수요 증가에 능동적으로 대처하고 안정적 전력공급을 위해 2011년 제주 추가 직류연계선과 2013년 LNG 발전소 건설을 제3차 전력수급기본계획에 반영 추진중이다. 이 논문은 제주 추가 직류연계선 및 LNG 발전소 건설 타당성, 사업여건의 변동에 따라 제주도의 전력공급신뢰도와 발전원 MIX 전망을 검토하였다.

• Fashion & Textile Research Journal
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• v.14 no.5
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• pp.758-765
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• 2012

As the 21st century is the post-digital era, a mix of the hard digital and the soft analog realm, the school uniform designs for the post-digital generation need to be changed within this paradigm shift. Thus, this study is conducted with the purpose of developing the school uniform design that reflects aesthetic value and sensitivity of the post-digital generation. The definition and background of the post-digital generation is reviewed and the values of this generation are drawn based on the theoretical research. Also, through the survey of 205 high school girls in Seoul, the purchase, wear & fit, and suggestions for improvement of present school uniforms are investigated. Based on the studies above, the guidelines for designing school uniforms for the post-digital generation are established and the products are developed.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.280-283
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• 2004

Today, the guide line of the SFRC mix design and the construction was not embodied, and the convenience of the practical application on the spot is not good. In this research, hence, the program which is optimized to result the mix proportion by the flexural strength and toughness, was developed to apply with ease SFRC on the practical spot. This program would minimize the number of trial mixes and achieve an economical and appropriate mixture. In addition, the theoretical background on which the program is based, will be the basis of the embodied method to mixing SFRC. New algorithm, in this research, was used to develop the mix proportioning program of SFRC. The new algorithm is the Harmony Search which is the heuristic method mimicking the improvisation of music players. And, beside to single fiber reinforced concrete, it was developed the program about the hybrid fiber reinforced concrete that two kinds of steel fibers, which have the different geometry, was reinforced. This will be able to keep the world trend to study, hence, offers the basis of the next generation research.

• 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.

• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.2
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• pp.13-26
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• 2011

The purpose of this study is to analyze the preference of design and body shape for korean baby-boom generation women. For this study, in-depth interviews were carried out to 11 women who were born in 1955~1963. They are called korean baby-boom generation. The results were as follows; 1) Korean baby-boom generation women care to their body shape, and they make much of the balance of body, not just looking slim. 2) Korean baby-boom generation women become more interested in their clothing, and they want to look with casual image than elegant image before. But overweight women preferred elegant image. 3) Korean baby-boom generation women prefer mix-match style for everyday clothes, but they prefer suit-set for formal wear. 4) When Korean baby-boom generation women choose of jacket or coat color, they consider more of their body-shape than season color. 5) Korean baby-boom generation women prefer plain style and jacquard with metal yarn. 6) Korean baby-boom generation women prefer out-door cloth fabric, at special time, they choose pure wool and pure silk. At ordinary time, they like more comfortable fabric like cotton mixed spandex or wool mixed spandex blends.

• Environmental and Resource Economics Review
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• v.15 no.2
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• pp.297-318
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• 2006

Imported natural gas has been consumed by urban gas use and generation sector in Korea. The share of generating sector in total demand for natural gas is only 33% at 2000. This paper examines the potential of natural gas use in generation sector in the future. We build some hypothetical but realistic scenarios reflecting rapidly changing economic environment. We used standard programs for plant mix decision under those scenarios. We found that it is very likely to have high gas demand in the future, if we remove the cross-subsidizing price structure.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.2
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• pp.8-17
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• 2005

This paper dealt with a kind of heterogeneous vehicle routing problem with known demand and time deadline of customers. The customers are supposed to have one of tight deadline and loose deadline. The demand of customers with tight deadline must be fulfilled in the deadline. However, the late delivery is allowed to customers with loose deadline. That is, the paper suggests a model to minimize total acquisition cost, total travel distance and total violation time for a fleet size and mix vehicle routing problem with time deadline, and proposes a heuristic algorithm for the model. The proposed algorithm consists of two phases, i.e. generation of an initial solution and improvement of the current solution. An initial solution is generated based on a modified insertion heuristic and iterative Improvement procedure is accomplished using neighborhood generation methods such as swap and reallocation. The proposed algorithm is evaluated using a well known numerical example.