• 제목/요약/키워드: TMP

검색결과 333건 처리시간 0.029초

Turbomolecular Pump 내 Rotor-Stator의 형상 변화에 따른 유동의 수치적 해석

  • 김인찬
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.98-98
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    • 2012
  • 최고진공도 10-10 mbar, 배기속도 2500 L/s를 구현할 대용량 복합 분자펌프(TMP) 설계를 위한 3차원 유동해석을 실시하였다. 진공도가 10-5 mbar 이상이 되는 고진공도에서는 Knudsen 수가 102~107에 이르러 분자간 충돌을 거의 무시할 수 있게 되며, 이때의 유체해석 방법으로서는 통상 희박기체 해석법으로 많이 쓰이는 Direct Simulation Monte Carlo (DSMC) 방법이나 Continuum fluid에 대한 Navier-Stokes 해석보다, 충돌이 없는 분자의 자유운동을 모사하는 Monte Carlo 방법이 더 적합할 수 있다. 본 연구에서는 다단계 rotor와 stator로 구성되는 복합분자 내 유동장에 Monte Carlo 해석법을 적용하여 유동해석을 실시하였다. 해석 방법의 타당성을 확인하기 위해 동일한 형상에 대해 Navier-Stokes 해석과 DSMC 해석을 병행하였다. 각각의 수치적 해석에서 공통적으로, TMP의 성능에 지배적인 영향을 미치는 설계변수는 rotor-stator의 날개각임이 확인되었고, 이 설계변수들의 최적값을 다양한 3차원 유동해석을 통해 도출하였다. 해석결과는 펌프설계에 적용되어 펌프 성능시험결과를 통해 확증된다.

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Biosynthesis of Carbohydrate associated with secondary Metabolites; Biosynthesis of dTDP-4-keto-6-deoxy-D-glucose by four enzyme reaction system

  • 오종민;이선구;김병기
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2001년도 추계학술발표대회
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    • pp.185-188
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    • 2001
  • We have developed a synthetic method for dTDP-4-keto-6-deoxy-D-glucose with four enzyme system. We have used crude extracts from cultures of Escherichia coli BL21 strains harboring plasmids containing different sources. dTDP-4-keto-6-deoxy-D-glucose was synthesized by the combination of thymidine-monophosphate kinase, acetate kinase, dTDP-glucose synthase and dTDP-D-glucose 4,6-dehydratase in a batch system, starting the reaction with dTMP. The enzymatic synthesis strategy allowed a dTMP conversion with a 95%.

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Influence of Base Paper Properties on Coating Penetration

  • Kim, Bong-Yong;Bousfield, Douglas W.
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2003년도 추계학술발표논문집
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    • pp.148-153
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    • 2003
  • The influence of sizing, fiber and pigment type on coating penetration, using commercial paper and two types of handsheets as the base paper which were prepared from thermomechanical pulp(TMP) and hardwood bleached kraft pulp(KP) sized internally with alkyl ketone dimmer(AKD), was studied in terms of characteristics of coating holdout. Laboratory rod draw down coater was used for surface sizing and coating application. Characterization of coating penetration was done by measuring the roughness of the backside of coating layer. The backside of the coating was exposed by dissolving the fibers in a solution of cupriethylenedimine(CED). Data show that internal sizing of base paper is effective and surface sizing is more effective to prevent coating penetration. Comparing between the two types of base papers, backside roughness of coating layer of TMP sheet is much larger and sizing is more effective to reduce coating penetration than those of KP sheet. With regard to pigment type, clay is more effective than calcium carbonate for better coating holdout.

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임베디드 네트웍용 프로세서 개발 (Development of Embedded Network Processor)

  • 유문종;최종운
    • 한국정보통신학회논문지
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    • 제5권6호
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    • pp.1078-1082
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    • 2001
  • 8비트 마이크로 프로세서인 TMP84C015과 RTL8019AS를 사용하여 이더넷 물리층을 구성한 뒤 Embedded HTTP서버를 구성하였다. 프로토콜의 사양을 최소한으로 선택한 뒤, 패킷 전송률을 최대화하기 위해서 어셈블리어로 코딩하였다. 서버 구현에 필요한 TCP, UDP, IP, ICMP, ARP 프로토콜이 내장되어 있으며, Client 측에서 각각의 프로토콜의 동작을 LabVIEW를 사용하여 확인하였다.

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장강식(長綱式) 초지시(抄紙時) 전료용(塡料用) 견운모(絹雲母) 첨가(添加)의 효과(效果) (Effect of Sericite on Pilot Fourdriner Paper Making for Loading)

  • 문수열;정대교
    • Journal of the Korean Wood Science and Technology
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    • 제14권4호
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    • pp.8-13
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    • 1986
  • To investigate effect of sericite on pilot Fourdrinier paper making for loading, with respectively 15% additive sericite on talc, we made newprint with TMP, and then tested sericite on talc, we made newprint with TMP, and then tested sericite and talc abrasion, physical and strength properites of the paper. Consequently, as a loading materials, sericite had outstanding properties different from talc from the result of this paper; 1. Sericite was a good loading materials because the quantity of abrasion was small. 2. Sericite had a good physical properties of Foudrinier paper because brightness. ash content and water absorption were high. 3. Newsprint paper strengthes of additive talc were nigher than those of additive sericite.

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BINARY TRUNCATED MOMENT PROBLEMS AND THE HADAMARD PRODUCT

  • Yoo, Seonguk
    • East Asian mathematical journal
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    • 제36권1호
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    • pp.61-71
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    • 2020
  • Up to the present day, the best solution we can get to the truncated moment problem (TMP) is probably the Flat Extension Theorem. It says that if the corresponding moment matrix of a moment sequence admits a rank-preserving positive extension, then the sequence has a representing measure. However, constructing a flat extension for most higher-order moment sequences cannot be executed easily because it requires to allow many parameters. Recently, the author has considered various decompositions of a moment matrix to find a solution to TMP instead of an extension. Using a new approach with the Hadamard product, the author would like to introduce more techniques related to moment matrix decompositions.

석산육교 공동충전을 위한 가소상 모르타르 충진(TMP)공법 적용 (The Application of TMP Method on Suk-San Highway Bridge)

  • 한복규;신관수;정해문;이재도
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.626-629
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    • 2006
  • Suk-San highway bridge, located on a soft ground environment, had been examined the current condition of settlement estimation throughout G.P.R(Ground Penetrating Radar), general observation and visual observation(video camera & scope). According to the above observations, the ground of this area has sunk about thirty centimeters since 1996. Also, currently, Suk-San highway bridge has been disjoining the gap between the structure and ground. Therefore, it is necessary to fill it up the gap. The purpose of this paper is to report the effects of Sunk-San highway bridge was observed by G.P.R. & general observation etc. and to present the results of repair of Suk-San highway bridge filling the gap up.

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On the reinforcement of straw pulp

  • Y. Yu;Kettunen;H. Paulapuro
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 1999년도 Pre-symposium of the 10th ISWPC Recent Advances in Paper Science and Technology
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    • pp.232-238
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    • 1999
  • The reinforcement of wheat straw pulp sheets with softwood kraft was studied, with special emphasis on the impact of softwood kraft beating and the proportion softwood kraft in straw pulp. the reinforcement was evaluated by measuring the tensile stiffness sand in-plane fracture behavior of samples. the results were compared with a mechanical pulp (TMP) and with a hardwood birch kraft, both reinforced with the same softwood kraft. Wheat straw pulp forms strong interfiber bonds. Therefore, its tensile stiffness and tensile strength are larger than TMP used. In-plane tear tests showed that a pure wheat straw pulp sheet has low fracture energy and correspondingly a narrow fracture process zone. The fracture energy of the reinforced straw sheets was found to increase linearly with the proportion of both unbeaten and beaten softwood pulps.

DECREASING CATIONIC DEMAND OF PEROXIDE-BLEACHED THERMOMECHANICAL PULP WITH PECTINASE ENZYME INCREASES FINES AND FILER RETENTION

  • Ian Reid;Michelle Ricard
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 1999년도 Proceedings of Pre-symposium of the 10th ISWPC
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    • pp.84-89
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    • 1999
  • Treatment with the enzyme pectinase has been reported to lower the cationic demand of thermomechanical pulp(TMP) bleached with alkaline peroxide in the laboratory. We have extended this discovery to bleached TMP produced industrially, and shown that commercial enzyme preparations can treat pulp within 15 minutes at the at the temperature and pH values prevalent in paper mills. About half of the cationic demand in the bleached pulp can be destroyed by pectinase. Dynamic drainage jar experiments show that the enzyme treatment improves the effectiveness of several cationic polymers to increase retention in the absence of retention aids or with non-ionic polymers, and does not damage the strength properties of the pulp. Pectinase could be easily incorporated into paper machine stock preparation systems to lower the charges of cationic retention aids needed in furnishes containing peroxide-bleached mechanical pulp.

분자 드래그 회전자 형상에 따른 복합분자펌프의 배기성능에 관한 실험적 연구

  • 황영규;권명근
    • 한국반도체및디스플레이장비학회:학술대회논문집
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    • 한국반도체및디스플레이장비학회 2006년도 춘계학술대회
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    • pp.202-205
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    • 2006
  • Recently, high vacuum pumps are widely used in the semi-conduction and liquid-crystal display ( LCD ) process. The composite-type high vacuum pumps are widely used in the various processes. In this study, the pumping performance of composite-type molecular pumps has been investigated experimentally. The experimented pumps are a compound molecular pump ( CMP ) and hybrid molecular pump ( HMP ). The CMP consists with helical-type drag pump, at lower part, and with turbomolecular pump ( TMP ), at upper part. The HMP consists with disk-type drag pump, at lower part, and with TMP, at upper part. The experiments are performed in the outlet pressure of $0.2\;{\sim}\;533\;Pa$. We have measured the ultimate pressure, compression ratio, and pumping speed

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