• 제목/요약/키워드: Drainability

검색결과 3건 처리시간 0.017초

하천합류부 구조에 따른 배수능력 해석 (Impact Analysis of Different Form on Drainability at River Confluence Area)

  • 안선복;진국신;전도석;지홍기
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2007년도 정기총회 및 학술발표대회
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    • pp.624-627
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    • 2007
  • There are many channel confluences existing in natural river systems, where the hydraulics are very complex because of the interactive between tributary and main river The RMA-2 model Is applied in this paper to model the confluence between Uksu Chun subriver and Nam Chun main river. Based on three types of assumed confluence forms, the model resuits present the hydraulics at channel confluence can be divided into several zones including a zone of separation immediately downstream of the junction branch channel, a maximum and minimum velocity region at upstream and downstream in the confluent channel, and a shear plane developed between the two combing flows at downstream of confluent channel. And the different types of confluent forms performs a very high effect on drainability of tributary, so it is very necessary to design a reasonable confluent forms.

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투수성콘크리트포장의 현장적용에 관한 연구 (A Study on the Field Application Porous Concrete Pavement)

  • 하재담
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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    • pp.613-619
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    • 1997
  • The present study has an objetive to define the characteristic of the Porous Concrete to be used in the resistant layers of the pavement. Up to the moment there is no material which is capable which is capable of satisfying the mechanical resistances and drainability, two characterstics which interves, and a detailled study has been carried out on the same order to obtain the porous concrete of this study. such as: Mode and time of compaction. type of cement, water/cement ratio, maxium size of aggregates, sieve test. incorporation of some additives and additions etc., among them emphasizing the use of a method of compaction vibro-compression in the laboratory with which an optimum compacting was reached, and can be obtanied on the site with a spreader rated with double tamper. With this porous concrete for this study whose dominating characteristics is the drainability jointly with a high mechanical resistance. a safe and silence firm is obtained, with can be a great diffusion in the near future, for its application on the pavements. Based on these works carried out, there was the first experience in the world of field application with 25cm of resistance layer of Porous Concrete Pavement in Salamanca, Spain.

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효소처리에 의한 제지적성 개선

  • 김형진;조병묵
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2000년도 춘계학술발표논문집
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    • pp.39-46
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    • 2000
  • In pulp and papermaking process, enzymatic treatment of pulp fibres has been a topic of increasing interest in last decade. Lots of patents, papers and research reports were published on the application of enzymes in the fields of enzymatic bleaching, deinking, slime control, pitch control, waste water treatment and fibre modification. Cellulase and hemicellulase are the principal enzymes used for the modification of fibre property. This study was carried out for determinating the behaviors of enzyme to pulp fibres. A commercial enzyme, Denimax BT which is consisted with cellulase and hemicellulase, was treated to the kraft pulp produced from domestic hardwood mixtures. Results were mainly concentrated on the behaviors of freeness, drainability and fines content of fibres, and physical properties of paper with enzyme treatment. The freeness levels and dewatering ability were developed, and the fines contents were decreased. The creation of fines were controlled by the method of pre-enzyme treatment prior to fibre beating. The mechanical strength of paper, like tensile, burst, tear strength and folding endurance, were remarkably improved by the pre-enzyme treatment.

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