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991.
992.
We report the experimental verification of the predicted chaotic mixing characteristics for a polydimethylsioxane microfluidic chip, based on the mechanism of multistage cross-channel flows. While chaotic mixing can be achieved within short passage distances, there is an optimal side channel flow pulsation frequency beyond which the mixing becomes ineffective. Based on the physical understanding of a Poincaré section analysis, we propose the installation of passive flow baffles in the main microfluidic channel to facilitate high-frequency mixing. The combined hybrid approach enables chaotic mixing at enhanced frequency and reduced passage distance in two-dimensional flows. 相似文献
993.
Yanyan Niu 《Geometriae Dedicata》2010,149(1):363-371
In this paper, we extend the maximum principle for (1, 1)-Hermitian symmetric tensor to a complete K?hler manifold with bounded
holomorphic bisectional curvature and nonnegative orthogonal bisectional curvature. We also achieve a maximum principle for
real (p, p)-forms on a compact K?hler manifold with nonnegative holomorphic sectional curvature and vanishing Bochner tensor. 相似文献
994.
995.
The connected dominating set (CDS) problem, which consists of finding a smallest connected dominating set for graphs is an NP-hard problem in the unit disk graphs (UDGs). This paper focuses on the CDS problem in wireless networks. Investigation of some properties of independent set (IS) in UDGs shows that geometric features of nodes distribution like angle and area can be used to design efficient heuristics for the approximation algorithms. Several constant factor approximation algorithms are presented for the CDS problem in UDGs. Simulation results show that the proposed algorithms perform better than some known ones. 相似文献
996.
In this paper, we concern the divergence Kohn-Laplace equation$$\sum\limits_{i = 1}^n {\sum\limits_{j = 1}^n {\left( {X_j^*({a^{ij}}{X_i}u) + Y_j^*({b^{ij}}{Y_i}u)} \right)} } + Tu = f - \sum\limits_{i = 1}^n {\left( {X_i^*{f^i} + Y_i^*{g^i}} \right)}$$ with bounded coefficients on the Heisenberg group ${{\mathbb{H}}^n}$, where ${X_1}, \cdots, {X_n},{Y_1}, \cdots, {Y_n}$ and $T$ are real smooth vector fields defined in a bounded region $\Omega \subset {\mathbb{H}^n}$. The local maximum principle of weak solutions to the equation is established. The oscillation properties of the weak solutions are studied and then the Hölder regularity and weak Harnack inequality of the weak solutions are proved. 相似文献
997.
998.
999.
This paper is concerned with the quantitative homogenization of 2m-order elliptic systems with bounded measurable, rapidly oscillating periodic coefficients. We establish the sharp convergence rate in with in a bounded Lipschitz domain in as well as the uniform large-scale interior estimate. With additional smoothness assumptions, the uniform interior , and estimates are also obtained. As applications of the regularity estimates, we establish asymptotic expansions for fundamental solutions. 相似文献
1000.
Summary: In this study, we used a facile approach to examine the evolution of fiber morphologies during electrospinning, via solidifying the newly electrospun polyacrylonitrile (PAN) nanofibers in an ethanol bath at different electrospinning distances (2 cm to 10 cm). It has been observed that a massive jet-thinning took place at the initial stage of whipping instability, followed by uneven fiber-stretching. The fiber-stretching at the later whipping stage was mainly concentrated on beaded fiber sections, which improved the uniformity of the resultant fibers. 相似文献