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181.
182.
周期B样条曲线的快速递推升阶方法 总被引:4,自引:0,他引:4
给出了一种快速的周期B样条曲线递推升阶方法及其算法,该算法的时间复杂性为O(nk),其中k和n k 1分别为分阶前周期B样条曲线的阶和节点数。 相似文献
183.
熊焱 《鞍山科技大学学报》2000,23(3):213-215
用单纯形方法解线性规划问题过程中出现退化情况时。可能出现循环现象。1976年,Bland提出一种避免循环的方法.本文对其做了一点改进。使其理论上比Bland方法迭代次数少.在计算机上更容易实现. 相似文献
184.
185.
Charles A. Micchelli Yuesheng Xu Haizhang Zhang 《Advances in Computational Mathematics》2008,28(2):157-169
It was observed in [4] that the Hilbert transform of the univariate B-spline preserves the B-spline recurrence. Motivated by this observation,
we characterize translation invariant operators that preserve the multivariate B-spline recurrence and analogous results are
also provided for the multivariate cube spline.
Charles A. Micchelli was supported in part by the US National Science of Foundation under grant CCR-0407476.
Yuesheng Xu was supported in part by the US National Science Foundation under grant CCR-0407476, by the Natural Science Foundation
of China under grant 10371122, by the Chinese Academy of Sciences under the program “One Hundred Distinguished Chinese Scientists”
and by Ministry of Education, People’s Republic of China, under the Changjian Scholarship through Zhongshan University. 相似文献
186.
This paper deals with a multi-server, finite-capacity queuing system with recurrent input and no waiting line. The interarrival times are arbitrarily distributed whereas service times are exponentially distributed. Moreover, the servers are heterogeneous and independent of each other. Arriving customers choose the server with the lowest index number among the empty servers. When all servers are busy at a time of an arrival, that arrival must leave the system without being served. The semi-Markov process method is used to describe this model and embedded Markov chain of the process is obtained. Furthermore, the Laplace–Stieltjes transform of the distribution of interoverflow times is derived which is the main objective of the paper. Finally, it is offered a new formulation for the loss probability which provides more efficient and rapid calculation is proposed. 相似文献
187.
Andrs F. Almeida-
auay Rosa María Benito Miguel Quemada Juan Carlos Losada Ana M. Tarquis 《Entropy (Basel, Switzerland)》2021,23(5)
Multiple studies revealed that pasture grasslands are a time-varying complex ecological system. Climate variables regulate vegetation growing, being precipitation and temperature the most critical driver factors. This work aims to assess the response of two different Vegetation Indices (VIs) to the temporal dynamics of temperature and precipitation in a semiarid area. Two Mediterranean grasslands zones situated in the center of Spain were selected to accomplish this goal. Correlations and cross-correlations between VI and each climatic variable were computed. Different lagged responses of each VIs series were detected, varying in zones, the year’s season, and the climatic variable. Recurrence Plots (RPs) and Cross Recurrence Plots (CRPs) analyses were applied to characterise and quantify the system’s complexity showed in the cross-correlation analysis. RPs pointed out that short-term predictability and high dimensionality of VIs series, as well as precipitation, characterised this dynamic. Meanwhile, temperature showed a more regular pattern and lower dimensionality. CRPs revealed that precipitation was a critical variable to distinguish between zones due to their complex pattern and influence on the soil’s water balance that the VI reflects. Overall, we prove RP and CRP’s potential as adequate tools for analysing vegetation dynamics characterised by complexity. 相似文献
188.
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190.
Liming Wu 《数学学报(英文版)》2000,16(3):369-394
In this paper we shall characterize the large deviation principles (abbreviated to LDP) of Donsker-Varadhan of a Markov process
both for the weak convergence topology and for the τ-topology, by means of a hyper-exponential recurrence property. A Lyapunov
criterion for this type of recurrence property is presented. These results are applied to countable Markov chains, unidimensional
diffusions, elliptic or hypoelliptic diffusions on Rienmannian manifolds. Several counter-examples are equally presented.
Received July 20, 1998, Accepted March 25, 1999 相似文献