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21.
Competitive sports analysis is a popular and valuable research topic in recent years. Sports are competitive, fast paced, and teamwork based. In this article, we introduce a generalized and effective system MatchOrchestra to analyze competitive team sports based on musical score and orchestra metaphor. MatchOrchestra provides views about player performance, team status, match tempo, player cooperation and confrontation, which can help analysts in performing specific analysis tasks. To demonstrate the usability of our proposed system, representative case studies were conducted on an NBA (National Basketball Association) game and also extend to apply in football match, which are both typical competitive sports matches. 相似文献
22.
Yanheng Ding Shixia Luan Michel Willem 《Journal of Fixed Point Theory and Applications》2007,2(1):117-139
We study existence and multiplicity of homoclinic type solutions to the following system of diffusion equations on
\mathbbR ×W{\mathbb{R}} \times \Omega
:
$
\left\{ {{*{20}c}
{\,\,{\partial}_t u - {\Delta}_x u + b(t,x) \cdot {\nabla}_x u + V(x)u = H_v (t,x,u,v),} \\
{ - {\partial}_t v - {\Delta}_x v - b(t,x) \cdot {\nabla}_x v + V(x)v = H_u (t,x,u,v),}\\
} \right.
$
\left\{ {\begin{array}{*{20}c}
{\,\,{\partial}_t u - {\Delta}_x u + b(t,x) \cdot {\nabla}_x u + V(x)u = H_v (t,x,u,v),} \\
{ - {\partial}_t v - {\Delta}_x v - b(t,x) \cdot {\nabla}_x v + V(x)v = H_u (t,x,u,v),}\\
\end{array} } \right.
相似文献
23.
天然二苯乙烯低聚物是一类自然界分布广泛的多酚化合物,因其结构复杂且生物活性多样而受到密切关注,但此类化合物天然资源的稀少极大限制了其构效关系的调查及活性药物的筛选。近年来许多化学家对此类低聚物的仿生合成方法做了广泛而深入的研究,已形成一个新的研究热点。本文详尽综述了迄今三十多年来二苯乙烯类低聚物的仿生合成研究进展,包括在不同介质中的酶催化或金属氧化剂催化的氧化偶联方法、光催化的异构化及强酸催化下的环合反应,由不同的二苯乙烯前体通过仿生合成途径,构建出结构多样的二苯乙烯低聚物。此外,本文对该类低聚物的仿生合成研究前景做了展望。 相似文献
24.
退偏度是衡量退偏器性能的主要参数.为了提高双光楔旋光退偏器的退偏性能,应用平均Mueller矩阵推导出双光楔旋光退偏器退偏度的理论表达式,并利用平均Mueller矩阵和斯托克斯矢量建立了退偏器偏振度与相关参量间的关系.通过对一阶贝塞尔函数求解,理论上就退偏器的退偏性能进行了解释.退偏度的大小与入射光的波长、光瞳半径、退偏器的结构角等参数有关.在Matlab软件环境下对理论结果进行了模拟计算.模拟计算结果表明:波长越短退偏越容易,在一定范围内适当增加光瞳半径或结构角可以提高退偏效果.理论结果与相应的实验结果相一致,证明了理论分析的正确性.为退偏器的优化设计、生产及使用提供了理论基础. 相似文献
25.
Structure,rheology and electrospinning of zein and poly(ethylene oxide) in aqueous ethanol solutions
This study provided a clear correlation of the structure and rheology of solutions with the morphologies of EFM made up of proteins and polymers. 相似文献
26.
酚氧树脂/蓖麻油交联聚氨酯 总被引:1,自引:1,他引:1
使2.2-(4’-羟基苯基)丙烷(双酚A)与环氧氯丙烷反应制得了带端羟基的酚氧树脂(HBA),将其与蓖麻油共混,用2.4-甲苯二异氰酸酯(TDI)作固化剂,制得了一系列交联聚氨酯。DSC和DMA测试结果表明,这种聚氨酯只有一个T_g。改变NCO/OH摩尔比及HBA/(HBA 蓖麻油)比可制得具有较好阻尼性能的聚氨酯材料。 相似文献
27.
聚氯乙烯(PVC)用作阻尼材料时多作成与高聚物的共混物,也有采用IPN的方法改善PVC的阻尼性能,前巳报导PVC-丁腈羟低聚物共混物有较佳的阻尼性质。本工作考察了PVC-PIB(聚异丁烯)组成及添加剂对共混物力学性能和动态力学性质的影响。 相似文献
28.
Lanthanide picrate complexes with the ligand N,N,N′,N′-tetraphenyl-3,6-dioxaactanediamide (tdd): [Ln(Pic)3(tdd)] (Ln = La, Nd, Eu, Tb, Er) have been prepared in a nonaqueous medium and characterized by elemental analysis, conductivity measurements, IR, and 1H-NMR spectra. The crystal structures of the complexes for Ln = Nd and Er were determined. The early lanthanide, NdIII, crystallizes as the nona-coordinate complex [Nd(Pic)3(tdd)]. 2 CH3CN in the monoclinic space group P21n with a = 11.384(2), b = 18.805(4), c = 27.526(5) Å, β = 99.41(1)°, V = 5832(2) Å3, and Dc = 1.58 gcm?3 for Z = 4. The structure was refined to R = 0.0505, based on 4772 observed Deflections. The late lanthanide, ErIII, forms an octa-coordinate complex [Er(Pic)3(tdd)]; crystals are triclinic, P1, with a = 12.449(2), b = 17.065(2), c = 26.243(4) Å, α = 72.12(1), β = 87.86(1), γ = 84.60(1)°, V = 5282(1) Å3, and Dc = 1.68 g cm?3 for Z, = 4. The structure was refined to R = 0.0469, based on 10666 observed reflections, The results reveal that tdd forms a ring-like structure with its four O-atoms, coordinating to the metal ions as multidentate ligand, together with one O-atom of the bidentate picrate. The structure of the complexes is greatly affected by the ionic radius due to participation of the picrates in coordination. 相似文献
29.
30.
In this paper, we investigate initial value problems for hyperbolic mean curvature flow with a dissipative term. By means of support functions of a convex curve, a hyperbolic Monge-Amp`ere equation is derived, and this equation could be reduced to the first order quasilinear systems in Riemann invariants. Using the theory of the local solutions of Cauchy problems for quasilinear hyperbolic systems, we discuss lower bounds on life-span of classical solutions to Cauchy problems for dissipative hyperbolic mean curvature flow. 相似文献
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