• 제목/요약/키워드: preserve

검색결과 2,259건 처리시간 0.239초

Vector decomposition of the evolution equations of the conformation tensor of Maxwellian fluids

  • Cho, Kwang-Soo
    • Korea-Australia Rheology Journal
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    • 제21권2호
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    • pp.143-146
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    • 2009
  • Breakthrough of high Weisenberg number problem is related with keeping the positive definiteness of the conformation tensor in numerical procedures. In this paper, we suggest a simple method to preserve the positive definiteness by use of vector decomposition of the conformation tensor which does not require eigenvalue problem. We also derive the constitutive equation of tensor-logarithmic transform in simpler way than that of Fattal and Kupferman and discuss the comparison between the vector decomposition and tensor-logarithmic transformation.

단기 전력우급계획에서의 부하관리 효과 분석연구 (The Analysis of Load Management Effect in Shor-Term Generation Expansion Planning)

  • 김준현;정도영
    • 대한전기학회논문지
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    • 제41권9호
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    • pp.994-1002
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    • 1992
  • With regard to price elasticity and cross elasticity of electricity, optimal generation expansion planning method including load management effect is suggested. In addition, optimal peak time price can be determined simultaneously, and we adopt peak time tariff as load management strategy. Instead of using hourly marginal demand curves where we can get customer surplus, we used chronological load curve with constraints to preserve social welfare. This method is proved useful in short-term generation expansion planning.

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생쥐 및 소초기배의 체외보존에 관한 연구 (Studies on In vitro Preservation of the Mouse and Bovine Embryos)

  • 권오경
    • 한국임상수의학회지
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    • 제8권1호
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    • pp.103-108
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    • 1991
  • It was carried out to investigate the effect of the kind of medium, the concentration of serum added and the temperature of storage on the survival of mouse and bovine embryos preserved In vitro. The survival of frozen-thawed mouse embryos after cooling at 4$^{\circ}C$ was also investigated. It was possible to preserve the embryos of mouse until 4 days and of cattle in a day without significant decrease of the survival rates. The survival rates of frozen-thawed mouse embryos after cooling at 4$^{\circ}C$ over 3 days were below 20%.

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생물학적 폭경을 고려한 보철임상 증례 (Clinical Cases on the Restorative Procedure Preserving the Biologic Width)

  • 김정호
    • 대한심미치과학회지
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    • 제8권1호
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    • pp.28-35
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    • 1999
  • The preservation of a healthy periodontal attachment is the most significant factor in the long-term prognosis of a restored tooth. The 'Biologic Width' is composed of the connective tissue attachment and the epithelial attachment in the dentogingival junction. The violation of the biologic width may result in a progressive inflammatory process and crestal bone loss. So a careful soft tissue management is needed to preserve it for the gingival health and an esthetic restoration. The following clinical cases show the five different situations of the violation of the biologic width and their management.

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터널굴착에 따른 인접 구조물 침하 억제효과에 관한 실내모형실험 (Model Tests for the Effect of Settlement Restraint of Adjacent Structure During Tunnel Excavation)

  • 유문오;임종철;고호성;박이근
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술발표회 논문집
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    • pp.141-148
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    • 2000
  • In this study, differential settlements of adjacent structure and behaviour of ground during tunnel excavation and the effect of micropile installed to preserve differential settlement of structure are measured and analyzed by model test. In the test results, the effective range of reinforcement is suggested.

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Extreme Preservers of Zero-term Rank Sum over Fuzzy Matrices

  • Song, Seok-Zun;Na, Yeon-Jung
    • Kyungpook Mathematical Journal
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    • 제50권4호
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    • pp.465-472
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    • 2010
  • In this paper, we consider two extreme sets of zero-term rank sum of fuzzy matrix pairs: $$\cal{z}_1(\cal{F})=\{(X,Y){\in}\cal{M}_{m,n}(\cal{F})^2{\mid}z(X+Y)=min\{z(X),z(Y)\}\};$$ $$\cal{z}_2(\cal{F})=\{(X,Y){\in}\cal{M}_{m,n}(\cal{F})^2{\mid}z(X+Y)=0\}$$. We characterize the linear operators that preserve these two extreme sets of zero-term rank sum of fuzzy matrix pairs.

EXTREME PRESERVERS OF TERM RANK INEQUALITIES OVER NONBINARY BOOLEAN SEMIRING

  • Beasley, LeRoy B.;Heo, Seong-Hee;Song, Seok-Zun
    • 대한수학회지
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    • 제51권1호
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    • pp.113-123
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    • 2014
  • The term rank of a matrix A over a semiring $\mathcal{S}$ is the least number of lines (rows or columns) needed to include all the nonzero entries in A. In this paper, we characterize linear operators that preserve the sets of matrix ordered pairs which satisfy extremal properties with respect to term rank inequalities of matrices over nonbinary Boolean semirings.

EXTREME PRESERVERS OF RANK INEQUALITIES OF BOOLEAN MATRIX SUMS

  • Song, Seok-Zun;Jun, Young-Bae
    • Journal of applied mathematics & informatics
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    • 제26권3_4호
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    • pp.643-652
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    • 2008
  • We construct the sets of Boolean matrix pairs, which are naturally occurred at the extreme cases for the Boolean rank inequalities relative to the sums and difference of two Boolean matrices or compared between their Boolean ranks and their real ranks. For these sets, we consider the linear operators that preserve them. We characterize those linear operators as T(X) = PXQ or $T(X)\;=\;PX^tQ$ with appropriate invertible Boolean matrices P and Q.

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