• 제목/요약/키워드: Economy efficiency

검색결과 831건 처리시간 0.023초

CVS-75모드에서 차량의 주행거리, 주행패턴 및 엔진 예열상태에 따른 배출가스 특성 (Emission Characteristics of Vehicles in CVS-75 Mode Under Various Conditions of Driving Distance, Driving Pattern, and Engine Pre-Heating)

  • 엄명도;백두성
    • 대한기계학회논문집B
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    • 제36권5호
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    • pp.503-508
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    • 2012
  • 최근에 들어서 이산화탄소가 지구온난화의 원인으로 알려져 있기 때문에 온실가스 문제는 이슈화 되어 왔다. 본 연구는 한국에서 운행 중인 차량에서 이산화탄소 배출가스 영향인자 특성을 파악하고자 했다. 가솔린 자동차 129대, 디젤자동차 100대, LPG 자동차 34대 차량을 차대 동력계에서 시험했다. 시험과정에서 이산화탄소, 일산화탄소 그리고 연료저감율을 측정했다. 실험모드는 현재 한국에서 경차의 배출가스를 규제하기 위해서 배출계수를 산정하기 위해 개발된 CVS-75 모드에서 이루어졌다. 실험 결과 배기량, 연료소비율, 연료 종류, 주행패턴, 마일수 그리고 이산화탄소 사이의 관련성이 조사되었다.

소규모 매립가스 자원화를 위한 마이크로터빈 열병합발전 및 유리온실 $CO_2$ 농도 증가 시스템의 타당성 연구 (Feasibility Study of Microturbine CHP and Greenhouse $CO_2$ Enrichment System as Small Scale LFG Energy Project)

  • 박정극;허광범;임상규;이인화
    • 신재생에너지
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    • 제5권2호
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    • pp.15-24
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    • 2009
  • As new small scale LFG (landfill gas) energy project model which can improve economic feasibility limited due to the economy of scale, LFG-Microturbine combined heat and power system with $CO_2$ fertilization into greenhouses was proposed and investigated including basic design process prior to the system installation at Gwang-ju metro sanitary landfill. The system features $CH_4$ enrichment for stable microturbine operation, reduction of compressor power consumption and low CO emission, and $CO_2$ supplement into greenhouse for enhancement plant growth. From many other researches, high $CO_2$ concentration was found to enhance $CO_2$ assimilation (also known as photosynthesis reaction) which converts $CO_2$ and $H_2O$ to sugar using light energy. For small scale landfills which produce LFG under $3\;m^3$/min, among currently available prime movers, microturbine is the most suitable power generation system and its low electric efficiency can be improved with heat recovery. Besides, since its exhaust gas contains very low level of harmful contaminants to plant growth such as NOx, CO and SOx, microturbine exhaust gas is a suitable and economically advantageous $CO_2$ source for $CO_2$ fertilization in greenhouse. The LFG-Microturbine combined heat and power generation system with $CO_2$ fertilization into greenhouse gas to enhance plant growth is technologically and economically feasible and improves economical feasibility compared to other small scale LFG energy project model.

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퇴적발효한 케이지 육계생분의 반추동물 사료적 가치 평가 (Evaluation on Ruminant Feed Value of Cage Broiler Excreta Processed by a Deepstacking Method)

  • 곽완섭;박종문;김연호;강준석;김영일;김원경
    • 한국축산시설환경학회지
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    • 제9권2호
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    • pp.113-122
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    • 2003
  • 육성 거세 한우(평균 체중 200kg)에게 6주 동안 배합사료의 16%와 볏짚의 48%를 대체하는 수준에서, 그리고 Holstein 비거세우(평균 체중 336 kg)에게 12주 동안 배합사료 4%와 볏짚18%를 대체하는 수준에서 퇴적발효한 육계생분­톱밥­왕겨 혼합물(DBSR 최종 함수율 45%)의 펠렛을 무제한 급여한 후 사료섭취량, 증체율, 사료효율, 경제성 및 도체 특성을 평가하였다. DBSR pellet의 기호성은 양호한 편이었다. 대조구와 비교해서 DBSR pellet 급여는 육성 거세 한우의 증체량(31.6 vs 36.6 kg), 일당 증체율(0.75 vs 0.87), 사료효율(7.23 vs 7.53)과 Holstien 비거세우의 증체량(148 vs 155 kg), 일당증체율(1.76 vs 1.84) 및 사료효율(5.69 vs 6.02)에 유의적 영향을 미치지 않았으며(P>0.05), 증체 당 사료비용은 축종별로 각각 18.5% 및 3.5% 절감되었다. Holstein 비거세우에의 DBSR pellet 급여는 도체중, 육량 및 육질에 아무런 영향을 미치지 않았다. 이러한 결과는 수분흡수제로서 톱밥, 왕겨와 혼합한 케이지 육계생분의 퇴적발효물은 육성비육우용 사료로서 효과적으로 이용될 수 있음을 시사하고 있다.

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조선후기 관영건축공사에 있어서 철물과 철제 연장의 공급체계에 관한 연구 -영건의궤(營建儀軌) 기록을 중심으로- (A Study on the Supply System of Iron Materials and the Tools in Government Constructions in the Late of Joseon Dynasty)

  • 이권영;김왕직
    • 건축역사연구
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    • 제16권3호
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    • pp.95-114
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    • 2007
  • Since the 17th century, the society of Joseon dynasty belongs to a period of rapid transition in many fields. As the building is a result to be produced on the basis of a society and economy, the general transition in a society is to be reflected into a process of building construction. Especially, a study on the material supply system of economic base in a process of building construction is one of vely important factors in an understanding or estimate of a building. On the premise, this paper is to examine the supply system of iron materials and the tools in the construction of the government managed buildings in the late of Joseon dynasty on a viewpoint of productivity. Construction reports and other documents in those days are examined for the study. Following conclusions have been reached through the study. 1) The general supply method of iron materials for a large-scale government construction was based on 'byulgong', that is, a kind of tribute. 2) Various methods were selected in the supply method of iron materials for government use in the late of Joseon dynasty. The priority order of choice in its government policy was put on an easiness of amount security, on a minimum of expenditure, and on an efficiency of construction execution. 3) The manufacturing technique of weaponry was used in the production method of iron materials and the tools for government use. The cooperation of the official, the army, and the merchant had improved the manufacturing technique of building construction.

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벤처기업과 일반중소기업의 조세지원제도의 유효성 및 정책적 개선에 관한 연구 (A Study on the Effectiveness and Policy Improvement of Tax-Aid Systems for Venture Business and Small & Medium Firms)

  • 서병우;문승권
    • 디지털융복합연구
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    • 제12권2호
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    • pp.173-182
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    • 2014
  • 정부는 창조경제에 의해 국가 성장과 효율성을 향상시키고자 한다. 본 연구에서는 벤처기업과 일반중소기업의 조세지원제도의 유효성으로서 조세부담율의 차이가 있는지에 대해 연구한다. 표본선정은 2010-2012년도 대한상공회의소, 중소기업청, 코스닥협회의 공시자료를 통해 수집하였다. 분석결과, 첫째, 벤처기업과 중소기업간, 세액공제 및 세금감면 등 조세지원을 받는 기업과 받지 않는 기업간에 조세부담률에서 차이가 있었다. 둘째, 벤처기업이 중소기업에 비해 조세부담율이 낮은 것으로 조사되었다. 본 연구결과에 의해 조세지원제도의 유효성을 확인하였으며, 새로운 정책적 대안으로 활용할 수 있을 것으로 본다.

LCC 분석을 고려한 일반 시설물에서 소형열병합발전의 최적 설계 (Optimal Design of Cogeneration System for General Facilities Considering LCC Analysis)

  • 강율호;구본철;황유진;송재도;정성일;이재근
    • 설비공학논문집
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    • 제21권8호
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    • pp.439-447
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    • 2009
  • Cogeneration system produces power as well as heat recovered from waste heat during power generation process. This system has higher energy efficiency than that of the power plant. In this study the optimal design for the cogeneration system with the increase of the capacity considering life cycle cost(LCC) analysis has been performed in the general facilities such as hotels and hospitals under the assumption of electricity cost of 95 won/kWh, the initial cost of cogeneration system of 1,500,000 won!kW and the value of 0.5${\sim}$1.0 in the ratio of heat to power. The optimal ratio of cogeneration capacity divided by average electricity load of facility was found out more than 0.5 in case of electricity cost with the increase of>30%, and the percentage of $CO_2$ reduction was about 9%. The most important factors in the economic analysis of cogeneration system was found out the electrity cost and the initial cost of cogeneration system. Also the ratio of heat to power at the value of>0.5 was not affected in the economy of cogeneration system, but was very important in the $CO_2$ reduction.

한국 에너지기업의 기술수준 결정요인 분석 (Determinants of Technological Level in Korean Energy Industry)

  • 이창수;윤성필;박중구
    • 에너지공학
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    • 제18권2호
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    • pp.75-86
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    • 2009
  • 본고는 한국 에너지 기업의 기술수준을 세계 최고수준과 대비하고, 이러한 기술수준을 결정하는 요인들을 기술경제이론과 경영자원의존이론을 통해 살펴보았다. 한국 에너지기업의 세계최고수준 대비 기술수준은 기술경제적 요인인 규모의 경제효과와 전방기업과 후방기업간 협력적 관계 등에 의해 긍정적 영향을 받고 있는 것으로 분석되었다. 반면, 국내시장의 경쟁정도, 연구개발투자 비중, 연구개발인력 비중 등은 국내 에너지기업의 세계 최고수준 대비 제품기술수준에 영향을 미치치 못하고 있는 것으로 분석되고 있다. 이 분석에서 얻을 수 있는 정책적 시사점은 한국 에너지기업의 기술수준을 제고하기 위해서는 국내시장을 더욱 경쟁적으로 전환해야 하며, 연구개발투자와 연구개발인력 등을 확충하고 부가가치사슬 상에서 전방기업과 후방기업 간 공동발전을 촉진하는 정책을 추진할 필요가 있다는 것이다.

석탄회를 활용한 경량기포 CLSM의 압축강도와 단위중량의 상관관계 (Correlation between Compressive Strength and Unit Weight of Lightweight Foamed Controlled Low Strength Material (CLSM) Using Coal Ash)

  • 이종휘;이혜진;천병식
    • 한국지반공학회논문집
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    • 제29권1호
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    • pp.39-47
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    • 2013
  • 석탄회를 활용한 CLSM(Controlled Low Strength Material)의 적용성이 증가됨에 따라, 본 연구에서는 경량기포CLSM의 압축강도와 단위중량과의 관계에 초점을 맞추어, CLSM 재료에 관련된 기초연구를 수행하였다. 일축압축강도는 구조물에 적용시 재굴착이 가능한지를 판단할 수 있는 기준이 되고 있으며 시험결과를 통해 경제성 및 효율성, 굴착성 등을 판단할 수 있는 중요한 배합설계변수이다. 그러나 CLSM의 일축압축강도는 재령 28일 기준으로 적용성을 판단하기 때문에, 정량적인 일축압축강도값을 알기 위해서는 배합 후 일정시간이 지나야한다. 본 연구에서는 저강도 고유동화재(CLSM)에 기포를 혼입하여 경량화시킨 경량기포 CLSM에 중점을 두어 경량기포 CLSM의 압축강도와 단위중량(기포슬러리 단위중량, 겉보기 단위중량)과의 관계를 분석하였고, 슬러리를 28일까지 양생시키지 않고 단위중량만으로 28일의 압축강도를 쉽게 예측할 수 있는 관계식을 제안하였다.

국제(國際) 네트워크를 통한 한국(韓國) 중소기업(中小企業) 국제화전략(國際化戰略)에 관한 연구(硏究) (The Internationalization Strategy of Small-and-Medium-Sized Enterprises in Korea through Internationl Network)

  • 오세영;이정연
    • 무역상무연구
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    • 제13권
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    • pp.767-804
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    • 2000
  • International network strategy is intended to examine the validity of existing network-centered theories in order to ascertain why small-and medium-sized enterprises are useful as a strategic correspondence to the internationalization trend. Small-and medium-sized enterprises can be estimated as being vital majorities in terms of their flexibility to meet changable conditions in international marketing compared with the conglomerates Therefore, their dependency on a few conglomerates for the international economy can be diverged. Generally, the successful internationalization of industries can be derived from the creation of suitable strategies for its competence and quality with the effective correction and completion of its strategy and tactics through mistakes. The internationalization strategy of small-and medium-sized enterprises should not be the reckless pursuit of internationalization that depends only on the increase of investment or the simple induction of the other conglomerates strategic models, but it should be accomplished through the evolution and practice of the concrete strategies that will be more proper for the enterprise's property and efficiency. The results of analyses with proof can be summarized with two effects in large in the process of internationalization of domestic small-and medium-sized enterprises. First, the capacity for internationalization of firms results from a long-term training procedure and continuous development of managing activities. Then in time this becomes an important element for the small-and medium-sized firms in terms with its position targeted international trading. However, the domestic enterprises are showing their abilities in the international competition in quantity, and trying to establish relationships between the enterprises through international networks. Second, statistics might not be meaningful in part because of the lack of data for analysis. It seems that more useful results will be derived from obtaining and utilizing sufficient information and from establishing an inter-relationship between the small-and medium-sized enterprises which are investing in foreign companies.

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트리즈(TRIZ)이론에 의한 패션디자인의 적용 - 레이 가와쿠보의 패션디자인을 중심으로 - (Applying TRIZ Theory to Fashion Design - Focused on Rei Kawakubo's Fashion Design -)

  • 김승현;김민자
    • 복식
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    • 제62권7호
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    • pp.79-96
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    • 2012
  • Creativity is a rising topic in the current society. The emphasis on creativity is valued as a key factor for success in all areas including but not limited to politics, economy, culture, arts and design. The field of Fashion design is probably one of the few areas that talk about creativity as a necessary quality to survive. The purpose of this study is to introduce TRIZ(Teoriya Reshniya Izobretatelsskikh Sadatch) as a theoretical tool to generate creativity in fashion design. TRIZ is a creative method of problem solving based on data analysis of outcomes invented by engineering. The fundamental concept of TRIZ has been researched through documentary studies, and practical case studies of product designs are used. Fashion design cases from Comme des Garcons by Rei Kawakubo are used to apply TRIZ in fashion design. Rei Kawakubo's design philosophy has been studied through fashion writings and visual sources in books, exhibition catalog, www. style. com and online shopping mall sites. This study has selected four principles among forty inventive theories of TRIZ: segmentation; asymmetry; consolidation; and preliminary action to apply to Rei Kawakubo's fashion design. As a result, TRIZ can be applicable to fashion design as a creative thinking methodology. By using the four principles of TRIZ, this study shows how Rei Kawakubo's design enhanced its efficiency and aesthetics of the products and was distinguished from existing items. It is meaningful to demonstrate a possibility of adopting engineering based creative methodology in fashion design to widen the perspective and to raise a question for the need of interdisciplinary creative methodology with traditional aesthetic approach in fashion design.