• Title/Summary/Keyword: dropping

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Synthesis of $TiO_2$Anchored on a Porous Clay Ceramic Support Using Dropping Precipitant Method (침전제 적하법을 이용한 $TiO_2$고정화 다공체 제조)

  • 신대용;한상목;김경남
    • Journal of the Korean Ceramic Society
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    • v.38 no.12
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    • pp.1097-1103
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    • 2001
  • TiO$_2$anchored on a porous clay ceramic support (PCS) for use in lightweight photocatalyst were synthesized by the dropping precipitant method. A PCS of macro and micro pore size of around several mm~${\mu}{\textrm}{m}$ in diameter were prepared by the rapid heat treatment at, 1,15$0^{\circ}C$ for 10 min from low grade of clay. The change in pH of reaction solution due to the different addition rate of NH$_4$HCO$_3$as a precipitant, the reaction temperature and the concentration of TiCl$_4$had a pronounced effect on the nature of precipitated TiO$_2$particles on the surface of a PCS and the crystal structure of precipitated TiO$_2$particles. At an addition rate of 0.8 ml/min of NH$_4$HCO$_3$and pH=6 of reaction solution, homogeneous precipitation of TiO$_2$particles on a PCS was achieved. TiO$_2$particles with anatase phase was precipitated on the surface of a PCS at the low concentration of TiCl$_4$, the high addition rate of NH$_4$HCO$_3$and the high reaction temperature.

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Fertilizer on Growth Characteristics and Yield of Fritillaria thunbergii Miquel (비료종류(肥料種類)에 따른 패모(貝母)의 생육(生育) 및 수량(收量))

  • Choi, In-Sik;Park, Jae-Seong;Lee, Je-Hong
    • Korean Journal of Medicinal Crop Science
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    • v.5 no.2
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    • pp.147-153
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    • 1997
  • This experiment was carried out to clarify the effect of different fertilizer on growth and yield of Fritjllaria thunbergii in Chungbuk Rural Development Administration from 1993 to 1995. Emergence date was faster about 1 to 5 days in fertilizer application than that of non-fertilizer, and emergence ratio was lower about 2.4% to 35.7% in fertilizer application than that of non-fertilizer. Plant height was longer about 2.8cm to 10.6cm in fertilizer application than that of non-fertilizer, and leaf length and width had same tendencies. Bulb height was increased about 0.1 to 0.2cm in fertilizer application than 1.9cm in non-fertilizer and bulb width was increased about 0.5 to 0.7cm in fertilizer application than 2.2cm in non-fertilizer. Total yield was increased about 27% in N-P-K fertilizer, 24% in compost, 23% in compound fertilizer for garlic and 21 % in fowl dropping manure than 572kg/10a in non-fertilizer. Yield of marketable goods was high about 79% in compost. 72% in compound fertilizer for garlic and fowl dropping manure, and 69% in organic fertilizer than 229kg/l0a in non-fertilizer. Therfore, in the cultivation of Fritillaria thunbergii the application of organic fertilizer such as compost and fowl dropping manure was considered more profitable than the application of chemical fertilizer in middle region.

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Low-Power MPEG-4 Video Decoding by Macro B1ock Dropping (매크로 블록의 생략을 통한 저전력 MPEG-4 비디오 재생법)

  • 김준희;김지홍;임성수
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.10b
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    • pp.655-657
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    • 2004
  • 본 논문에서는 휴대용 기기와 같은 에너지의 제약이 있는 환경에서 MPEG-4 비디오를 디코딩할 때, 일부 매크로 블록을 생략함으로써 에너지 소모를 줄이고 재생 품질의 저하를 최소화하는 방법을 제안한다. 이러한 방법을 실제 참조 보드에서 구현, 검증한 결과 매크로 블록 생략에 의해 재생 품질에의 영향을 최소화하면서 30% 정도까지 재생 에너지의 소모를 줄일 수 있었다.

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An Analysis on the Effect of Packet Dropping Attacks in Wireless Ad hoc Networks (애드 혹 네트워크상의 패킷 폐기 공격의 영향 분석)

  • Kim, Sang-Soo
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.11a
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    • pp.61-63
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    • 2005
  • 본 논문에서는 무선 애드 혹 네트워크상의 패킷 폐기 공격의 영향을 분석하고 시뮬레이션을 통해 그 효과를 측정하였다. 시뮬레이션 수행 결과 RREQ 패킷을 폐기한 경우에는 네트워크에 미치는 영향이 적은 반면, RREP 및 DATA 패킷을 폐기한 경우는 네트워크의 전송 효율이 떨어졌으며. 또한 패킷을 폐기하는 악성노드가 많을수록 데이터의 전달율이 감소하고 하나의 데이터를 전송 하는데 필요한 제어 패킷의 수가 늘어남을 알 수 있었다. 시뮬레이션을 통해 분석된 결과를 바탕으로 패킷 폐기 공격의 징후를 미리 검출하거나 공격 형태를 식별하는 기초 자료로 활용가능 할 것이다.

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Effect Analysis of Generator Dropping Using Wavelet Singular Value Decomposition (발전기 탈락 시 Wavelet Transform과 Singular Value Decomposition을 이용한 특성 분석)

  • Noh, Chul-Ho;Kim, Won-Ki;Han, Jun;Kim, Chul-Hwan
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.49-50
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    • 2011
  • 본 논문에서는 WT(Wavelet Transform)와 SVD(Singular Value Decomposition)를 함께 사용한 WSVD(Wavelet Singular Value Decomposition)를 이용하여 발전기 탈락 시의 전압 변동 특성을 분석하였다. WSVD 특성 분석을 위해 부산 지역의 345kV급 송전계통을 EMTP-RV로 모델링하였으며, 이 계통모델에서 발전기 탈락을 모의하였다. MATLAB을 통해 이 때 측정된 전압의 WSVD를 계산하여 발전기 탈락에 따른 특성을 분석하였다.

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A Study on Packet Dropping Policies (패킷 폐기 정책에 관한 연구)

  • 류동렬;육동철;박승섭
    • Proceedings of the Korea Multimedia Society Conference
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    • 2000.04a
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    • pp.17-21
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    • 2000
  • TCP 프로토콜과 ATM 프로토콜과의 형태 및 제어방식의 차이로 인한 이질성 문제 때문에 ATM 층에서 한 개의 셀 손실은 상위 TCP층에서 하나의 패킷 손실을 초래하게 되어 망에 대한 충분한 QoS를 제공하지 못한다. 이러한 문제들을 해결하기 위해 처리율면에서 Early Packet Discard(EPD)와 공정성면에서 Selective Packet Discard(SPD), Fair Buffer Allocation (FBA) 등이 제안되었다. 본 논문에서는 ATM상에서 TCP 성능성향을 위해 기존의 알고리즘과 제안한 알고리즘에 대하여 비교분석하고 , VC의 수를 가변적으로 변화시켜도 제안한 알고리즘은 SPD나 FBA보다 나은 공정성을 보였고, 처리율면에서는 차이가 없음을 시뮬레이션결과를 통해 나타내었다.

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Dynamic and Strict Packet Dropping Mechanism for Assured Forwarding Classes (Assured Forwarding 클래스를 위한 동적 엄격 패킷 폐기 메커니즘)

  • Kim, Su-Yeon;Lee, Ho-Gyun;Kim, Cheol-Beom
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.11S
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    • pp.3251-3259
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    • 1999
  • In this paper, we present a new mechanism applying more strict priority than RIO mechanism proposed as a drop precedence policy of AF classes in differentiated services. In this mechanism, applying strict priority to drop precedence policy, we get better performance on priority level. Simulation results indicate that the proposed mechanism may provide more efficient and more strict priority transmissions as compared to RIO regardless of traffic load.

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Efficient Implementation Techniques the Dual Simplex Method (쌍대단체법의 효율적인 구현을 위한 기법)

  • 임성묵;박찬규;김우제;박순달
    • Korean Management Science Review
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    • v.16 no.1
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    • pp.1-9
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    • 1999
  • The purpose of this paper is to develope efficient techniques for implementing the dual simplex method. In this paper we proposed one artificial row technique to get an initial dual feasible basic solution, a dual steepest-edge method coupled with a dropping row selection rule, and an anti-degeneracy technique which resembles the EXPAND procedure for the primal simplex method. The efficiency of the above techniques is shown by experiments. Finally, the dual simplex method is shown to be superior to the primal simplex method when it is used in the integer programming.

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Sealant for LCD Panel (LCD Panel용 Sealant)

  • Cho, Jung-Hwan;Cho, Kyu-Won;Kim, Myeong-Koo;Lim, Young-Taek;Park, Joo-Hyeon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.317-317
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    • 2006
  • This study is about Sealant for LCD panel which used m manufacture of liquid crystal display device with LC dropping method, with the least contamination of liquid crystals, the best adhesion of glass and Improvement of photoreaction for shaded area.

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