• Title/Summary/Keyword: self-construction

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Allowable Amount of Bed Inventory in a 300 MW Class Circulating Fluidized Bed Boiler (300 MW 급 유동층보일러에서 적정 층 물질량 산정)

  • Kim, Woo-Yong;Yoo, Ho-seon
    • Plant Journal
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    • v.14 no.2
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    • pp.33-38
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    • 2018
  • The CFB boilers technology is facing a number of challenges. Among them, boiler tube erosion, sintering by bed inventory overheating and high self consumed service power are major ones. This study was conducted to obtain allowable bed inventory with the Yeosu Power Plant, a 300 MW class CFB boiler. For the test, bed pressure was reduced from design pressure of 4.5 KPa to 2.5 KPa by reducing bed inventory, at fixed turbine output, coal consumption rate and air flow. Consequently, reducing the lower bed inventory is effective to decrease bed temperature but excessive reducing might increase bed temperature due to lack of circulating fluidized materials. Also, in case of the Yeosu Plant boiler using subbituminous coal as its primary fuel, its bed temperature change is highly affected by not only the amount of bed inventory, but also the boiler capacity and coal contents.

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A Study on the Mid-Long Term Direction for Development of Software Cost Estimation Guidelines (소프트웨어 사업대가기준 중장기 발전 방향에 관한 연구)

  • Kim, Woo-Je;Kwon, Moon-Ju
    • The Journal of Society for e-Business Studies
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    • v.15 no.1
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    • pp.139-155
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    • 2010
  • The purpose of this paper is to develop a framework of software cost estimation guidelines and to derive a mid-long term direction for development of the software cost estimation guidelines. In this paper, all the steps in the software life cycle are researched in the view of cost estimation, and current software cost estimation guidelines and models have been reviewed and analysed first. Second, a plan to separate unit cost per function point from standard procedure in current software cost estimation guidelines is presented to strengthen maket self-regulating function as a mid-long term developmental direction for software cost estimation guidelines. Third, construction of cost repository, making standard procedure for software cost estimation guidelines, development of various kinds of software cost estimation models, and a system for experts on software cost estimation are presented as the prerequisites for the future model framework of software cost estimation guidelines. Finally a roadmap for establishing the future model is proposed.

The Changes of Environmental Consciousness and the Formation of a Local Community through Participating in a Local Problem (지역환경문제 참여를 통한 환경의식 변화와 지역공동체 형성)

  • Lee, Hyun-Ae;Kim, Jong-Wook
    • Hwankyungkyoyuk
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    • v.17 no.2
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    • pp.94-105
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    • 2004
  • The purpose of this study is to understand what kind of effects a local residents’ participation on a local environmental problem has on the Environmental consciousness of the resident, and on the local community. I (researcher) employed qualitative research methods on the residents' environmental movement, which claimed to preserve the Sung Mi Mountain from the Seoul City Hall's plan of the water reservoir construction. I tried to understand the participation motivation and participating actions, and also the changes and effects the participation brought at both a personal, and community level. The data were gathered by means of in-depth interview with the local residents and unstructured questionnaire. At first, through the residents' environmental movement, the participants acquired a growth in environmental consciousness. For example, they obtained better understanding of the environment, change of attitude to environment, and participation function. Secondly, it is meaningful that a local tie intervened by the environment, enforced self-governing, and shows how community sentiment plays an important role for local community organization. Moreover, the environmental movement contributed to developing a ‘culture for participation’. In conclusion, participating in a local environmental problem can be an integration of learning and practice and also leads to reflective thinking about the relationship not only between human beings and nature, but also among human beings. In addition, it can buildup a systemic cooperation for local problem-solving and the ability to make an alternative culture in the community. These are the significances of the local environmental problem-participation on the environmental education.

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A study of The New Generation Women's Culture : Women’s Culture (신세대여성들의 화장경험을 통해 본 여성문화 드러내기와 그 저항성에 관한 연구)

  • 이현주
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.25 no.3
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    • pp.101-122
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    • 1999
  • The history of make-up can go back to the beginning of human being and it can’t be separated from women’s life. The change of history and women's position have given make-up different form and meanings. So make-up becomes another text which can read social·cultural specialty. This study has tried to find out make-up as women culture for women have experienced make-up in a specific situation for a long time and a suit of make-up experience from self-retrospect and made an open channel for women and this paper checked out the possibility of alternative make-up culture. This research used new audience theory of cultural studies which is used for communication study and studied active meaning-construction process and its resistance pleasure. This study saw women as independent subjects not passive victims and how make-up has been different meanings in women’s life. And what pleasure is made and how the way of resistance made constructed in the regulation of make-up.

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우리나라의 브랜드 쌀 생산 및 이용현황

  • 최해춘
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2002.08a
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    • pp.46-53
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    • 2002
  • The self-sufficiency of rice production was attained in 1975 through development of Tongil-type high-yielding rices and rapid dissemination to farmers and innovation of cultivation technologies, so-called "green revolution" in Korea. It can be continued during the last twenty seven years except some years with meterological disasters. The national average of milled rice yield per ha was only 3.1 ton at the first half of 1960′s, but it drastically increased to 5.0 ton at the 2nd half of 1990′s. Also, the rice quality was highly improved through the continuous varietal improvement of high-yielding japonica rice cultivars. The amounts of rice stock will go beyond about 1.9 million tons in 2002 due to the recent continuos bumper rice crop and relatively rapid reducing in rice consumption. There are so many rice brands over 1,200 in Korea, but most of rice commodities are not enough controlled in terms of marketing quality and palatability of cooked rice. Although the most rice brands are not properly controlled in quality management, its average level of grain quality is largely improved through the continuously increased diffusion of newly-developed high-quality rice cultivars since 1991. The rapid construction of rice processing complex(RPC) since 1992 also accelerates the production and distribution of brand rices. Especially, about half of distribution amounts are covered by brand rice commodities of the agricultural cooperative associations. The rice is mainly consumed by the type of cooked rice. The amounts of rice consumption for food processing is only below 4% of total rice consumption. The processed rice foods is mainly consumed as various processed cooked rices, rice cakes, and rice wines.

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Fabrication and Characteristics of HTS Field Winding of a 100 hp Synchronous Motor (100마력 동기전동기용 고온초전도 계자권선 제작과 특성)

  • Sohn Myung-Hwan;Baik Seung-Kyu;Lee Eon-Young;Kwon Young-Kil;Jo Young-Sik;Moon Tae-Sun;Kim Yeong-Chun;Kwon Woon-Sik
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.54 no.2
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    • pp.88-93
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    • 2005
  • To develop a 100 hp high temperature superconducting(HTS) motor with high efficiency first in Korea, we fabricated a HTS field winding and test. HTS field winding is composed of sixteen HTS race track shaped coils wound with stainless steel-reinforced Bi-2223 tape conductor by react and wind fabrication method. Nomex paper was used for electrical insulation. Each of four magnet pole assemblies was constructed with four double pancake sub-coils, mechanically stacked and electrically in series. Four magnet assemblies were fixed on an aluminum support structure to make effective heat transfer. The Critical current (Ic) was 41.5A at 77K and self field. However the lowest Ic value of sub-coils was 35A. Joule heat generated by each joints between sub-coils was lower than 1mW at 77K and 34A. And Joule heat generated by the joints between field coils was lower than 10mW at 77K and 34A. Joule heat of the whole field winding was 1W at 77K and 32A. And so, the lowest Ic value of sub-coils was more important than Joule heats generated by all joints. The operating current must be lower than the lowest Ic of all the sub-coils. In this paper, design, construction and testing of HTS field winding, Joule heat generated by the joints, and operating current were discussed.

An Analysis of Horizontal Behaviour of H-Pile under Mechanically Stabilized Earth Wall Abutment (보강토 교대 하부 H-Pile 수평 거동특성 연구)

  • Kim, Nagyoung;Jeon, Kyungsoo;Lee, Yongjun;Jun, Jintaek;Shim, Jaewon
    • Journal of the Korean GEO-environmental Society
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    • v.9 no.2
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    • pp.47-59
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    • 2008
  • Application of mechanically stabilized earth wall (MSEW) abutment has been rapidly increasing in United States of America, Pennsylvania since 2002. MSEW is effective for reducing construction cost and period compared to general concrete reinforced wall. In the paper, theoretical background and conventional criterion of MSEW abutment that is widely used abroad are analyzed. Based on the results, application of suitable MSEW abutment to domestic bridge type is examined. For the application of MSEW abutment in Korea, load interacting with upper shoe in domestic bridge types and structural analyses of beam seat and pile are investigated. As a result, all applications are possible except for PSC BOX Bridge that has heavy self-weight of girder. Through two and three dimensional numerical analyses, horizontal behaviour mechanisms between pile and MSEW were analyzed and field tests are also carried out for seven piles behind earth walls. From results of field tests, it is confirmed that an angle of internal friction of backfill material needs to be greater than 34 degree to use H-Pile as foundation of MSEW.

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A Study on contemporary space in Ubiquitous society - Focusing on Interactive space - (유비쿼터스 사회에서 나타나는 현대 공간에 관한 연구 - 인터렉티브 공간을 중심으로 -)

  • Koh, Gwi-Han
    • Korean Institute of Interior Design Journal
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    • v.21 no.3
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    • pp.50-57
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    • 2012
  • In Ubiquitous era. architecture is not the old building adapting ubiquitous technology. In order to take the role as new architectural paradigm in space, environment and technology, it has to develop technology continuously and experimental architecture at the same time. it must have co-evolution of architectural field and others through organic network. by that, the evolution of space will be in the way that combines space which is responded to human emotion and user-centric human-friendly. It will be the new paradigm of Ubiquitous digital space. Digital technology resulted in a change to a society as well as to the life of human and its way of thinking. Due to those changes, new terms or concepts come out and a new meaning is added to the conventional concepts. This aims to examine type of spatial contexts for interaction design experience. This study is performed through Literature research for theory by interactive space and case studies for construction elements to design. The range of case study is limited to interaction space in addition of interactive elements and user interface. And analysis conclusion is show the many type, First, Interactive space has special purpose for make a interaction by intelligent elements.(sensor, program, algorithm, New-technology) Second, Interactive space was cooperation with various professional for space purpose. Third. Interactive space is self-develop by algorithm, program, sensor network and that is harmonize with user. finally. Interaction space is show the temper elements about allness, metastatic, activeness, liquidity, relationship. That was written by ecological theory.

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Characteristics of Dynamic Compaction Energy for a Non-plastic Dredged Soil (비소성 준설토의 동다짐 에너지 특성 연구)

  • Hwang, Seong Chun;Yoon, Sang Chun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.6
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    • pp.110-117
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    • 2011
  • Seashore landfill projects use undersea pump dredging method for construction of airport and factory site. Coarse grain soil from the dredging is considered for use at inland. West sea shore bottom consists of primarily coarser grained silt-sand and this component contains far more percentage than is the case with East sea and South sea area. This soil shows very different characteristic at consolidation and compaction behavior. This research targets to utilize this type of dredging soil. Test specimen is from West sea (Saemangum) dredged soil landfill site. Model analysis is done for getting prediction of original soil relative density and N-value from dynamic compaction energy variance. Dynamic compaction energy is calculated for efficient foundation design.

Evaluation of Setting Delay in Mortar Adding Superplasticizer Using Electrical Resistivity Measurement (전기비저항 측정법을 이용한 유동화 모르타르의 응결 지연 현상 평가)

  • Lee, Hanju;Yim, Hong Jae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.22 no.6
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    • pp.9-15
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    • 2018
  • According to the development and use of self-consolidating concrete in field, interest in material properties of early-age concrete is rising. Setting time with hydration process of cement is one of significant indicator to evaluate the early-age material properties of concrete, various nondestructive methods including penetration resistance measurement have been proposed to estimate setting time. This study performed an experimental approach to evaluate setting time delay in mortar adding superplasticizer using electrical resistivity measurement. For this purpose, total nine types of mortar samples were prepared, and its electrical resistivity was monitoring during 24h after mixing. From the experimental result, rising time of electrical resistivity was used to evaluate setting delay of mortar, and penetration resistance was also measured for comparison. In addition, dynamic elastic modulus and compressive strength of 1day mortar were measured to investigate a possibility the use of electrical resistivity measurement for evaluation of early-age material properties.