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91.
王晓瑛 《纯粹数学与应用数学》2002,18(4):367-370
构造了一类新的分数布朗运动模型,它不同于Mandelbrot,Barton及Decreusefond等人所定义的分数布朗运动模型。 相似文献
92.
93.
本文在M ogens B ladt和T ina H av iid R ydberg无市场假设,仅利用价格过程的实际概率的期权保险精算定价模型的基础上,得出了标的资产服从几何分数布朗运动的欧式期权定价公式,并说明了几何布朗运动是本文的一种特殊情况. 相似文献
94.
V. A. KHATSKEVICH V.A. SENDEROV 《数学学报(英文版)》2006,22(6):1687-1694
The operator sets, which are the subject of this paper, have been studied in many papers where, under different restrictions on the generating operators, convexity, compactness in the weak operator topology, and nonemptiness were proved for sets of different classes under study. Then the results obtained were used in these papers to solve several applied problems. Namely, they played the key role in establishing the dichotomy of nonautonomous dynamical systems, with either continuous or discrete time. In the present paper, we generalize and sharpen the already known criteria and obtain several new criteria for convexity, compactness, and nonemptiness of several special operator sets. Then, using the assertions obtained, we construct examples of sets of the form under study which are nonconvex, noncompact in the weak operator topology, as well as empty, and are generated by "smooth" operators of a special class. The existence problem for such sets remained open until the authors of this paper announced some of its results. 相似文献
95.
The fluorescence dynamics parameters of the fluorescent transient flavin-luciferase species from the typesVibrio fischeri andPhotobacterium leiognathi are presented. The fluorescence anisotropy decay is a single exponential function for both types. The correlation time is 70 ns for theP. leiognathi fluorescent transient intermediate (2°C, aqueous buffer, pH 7.0), consistent with the rotational correlation time of the luciferase macromolecule (77 kD) to which the flavin fluorophore is rigidly attached. In contrast, for theV. fischeri species the observed correlation time for the anisotropy decay function is 133 ns. This suggests that protein self-association occurs in theV. fischeri case and this is confirmed by filtration, where the fluorescent transient fromV. fischeri does not pass through a 100,000 molecular weight cutoff membrane, whereas theP. leiognathi species does. The filtration method also demonstrates self-association in the luciferase peroxyflavin and photoflavin fromV. fischeri. A monomer-dimer equilibrium also explains the previously reported high correlation times for theV. harveyi luciferase-flavin species. It is proposed that the self-association competes with the lumazine protein interaction in the bioluminescence reaction. 相似文献
96.
Integrated Groups and Smooth Distribution Groups 总被引:1,自引:0,他引:1
Pedro J. MIANA 《数学学报(英文版)》2007,23(1):57-64
In this paper, we prove directly that α-times integrated groups define algebra homomorphisms. We also give a theorem of equivalence between smooth distribution groups and α-times integrated groups. 相似文献
97.
Solubility of carbon dioxide in aqueous solutions of sodium chloride: Experimental results and correlation 总被引:2,自引:0,他引:2
The solubility of carbon dioxide in aqueous solutions of sodium chloride was measured in the temperature range from 40 to 160°C, up to 6 mol-kg salt solutions and total pressures up to 10 MPa. Pitzer's(1) equations as well as the Chen and Evans(2) model were used to correlate the new data. Results are reported and compared to literature data and correlations. 相似文献
98.
99.
用分数延迟改进基音预测的CELP编码方案 总被引:2,自引:0,他引:2
在CELP编码器中,通常用延迟为抽样间隔整数倍的长项预测器表征浊音语音的准周期性,然而在低比特率,这种限制降低了编码器的性能。本文在介绍了CELP编码器原理及激励码本构成后,重点研究了一种新型的基音预测方法;分数延迟基音预测,计算机模拟结果表明,这种方法能对浊音进行更准确的表达,尤其对女性讲话者明显改善了语音质量。 相似文献
100.
The development of future mobile networks will be driven, in large part, by content and web based services. In this paper,
we examine several performance, scalability and architectural challenges faced by future mobile web applications and how advanced
mobile content delivery techniques can address these challenges. We review existing content delivery using a taxonomy that
consists of three categories: network scaling, end system acceleration, and content and protocol optimization. While wireline
content delivery focuses on network and server scalability, mobile content delivery will likely benefit most from optimizing
radio link usage. We also present our ongoing work in this area, which extends the functionality of edge caching to the terminal,
uses user interest correlation information to maintain low terminal power consumption and adds a new dimension to radio resource
management.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献