• 제목/요약/키워드: city gas network

검색결과 22건 처리시간 0.017초

가정.상업부문 이용을 위한 산업체 폐열특성 연구 (A Study on the Characteristics of Waste Heat from the Industrial Complexes for Residential and Commercial Sectors)

  • 최영찬;박태준;홍재창;조선영
    • 에너지공학
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    • 제8권2호
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    • pp.242-247
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    • 1999
  • 각종 산업단지 및 발전소에서 배출되는 막대한 양의 폐열을 회수하여 재활용하기 위하여 전국 7개 지역 11개 공단에 대한 폐열 특성분석을 실시하였다. 본 연구는 도시종합에너지시스템 연구의 일환으로 산업체 폐열을 배후도시의 주거 및 상업지역에 공급.이용 가능성을 검토하였다. 검토대상 공업단지의 조사된 폐열량은 148,913 TOE/년으로 나타났으며, 온도범위는 $0^{\circ}C$~20$0^{\circ}C$가 83%, 그리고 배가스 형태로 배출되는 폐열이 전체의 82%를 차지하는 것으로 나타났다. 이들 조사대상 공업단지 중 폐열량이 집중된 4개 지역 (대구공단, 울산 석유화학단지, 여천 석유화학단지 및 전주공단)에 대한 폐열특성도 상세하게 조사되었으며, 이들 공단의 조사된 폐열량은 114,402 TOE/년으로 조사된 총폐열량의 77%에 해당하며. 이중 배가스는 87%, 온도범위는 $0^{\circ}C$~20$0^{\circ}C$의 폐열이 대부분인 것으로 나타났다. 또한, 18.1 million TOE/년의 폐열이 화석연료를 사용하는 발전소로부터 발생되며, 이중 95%가 복수냉각기에서 배출되는 27$^{\circ}C$~34$^{\circ}C$ 범위의 저온폐열이며, 나머지 5%(894,800 TOE/년)가 연도 배가스 형태로 배출되고 있는 것으로 조사되었다.

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학교시설 건설공사의 작업분류체계 구축 및 단위작업별 선후행 관계 분석 (Development of Work Breakdown Structure and Analysis of Precedence Relations by Activity in School Facilities Construction Work)

  • 방종대;손정락
    • 토지주택연구
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    • 제8권3호
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    • pp.189-200
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    • 2017
  • The work breakdown structure and the precedence relations by work activity are very important because they are the basic data for estimating the construction duration in the construction work. However, there is no standard to accurately estimate the construction duration since the size of the school facilities construction is smaller than the general construction work. Therefore, some schools are unable to open in March or September and the delay of the construction duration can cause damage to the students. To solve this problem, this study developed a work breakdown structure of school facilities construction work and analyzed the precedence relations by work activities. The work breakdown structure of the school facilities construction is composed of three steps. The operations corresponding to level 1 and level 2 are as follows. (1) 2 preparatory work categories; preparation period and temporary construction. (2) 17 architectural work categories; temporary construction, foundation & pile work, reinforced concrete work, steel roof work, brick work, plaster work, tile work, stone work, waterproof construction, wood work, interior construction, floor work, metal work, roof work, windows construction, glazing work and paint construction. (3) 7 mechanic and fire work categories; outside trunk line work, plumbing work, air-conditioning equipment work, machine room work, city gas plumbing work, sanitation facilities and inspection & test working. (4) 4 civil work categories; wastewater work, drainage work, pavement work and other work. (5) 1 landscaping work categories; planting work. The work breakdown structure was derived from interviews with experts based on the milestones and detailed statements of existing school facilities. The analysis of precedence relations by school facilities work activity utilized PDM(Precedence Diagramming Method)which does not need a dummy and the relations were applied using FS(Finish to Start), FF(Finish to Finish), SS(Start to Start), SF(Start to Finish). The analysis of this study shows that if one work activity is delayed, the entire construction duration may be delayed because the majority of the works are FS relations. Therefore, it is necessary to use the Lag at the appropriate time to estimate the standard construction duration of the school facility construction. Lag is a term used only in the PDM method and it is used to define the relationship between the predecessor and the successor in creating the network milestone. And it means the delay time applied to the two work activities. The results of this study can reasonably estimate the standard construction duration of school facilities and it will contribute to the quality of the school facilities construction.