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排序方式: 共有1108条查询结果,搜索用时 15 毫秒
31.
In this paper, by using the concept of (A,η)-accretive mappings and the new resolvent operator technique associated with (A,η)-accretive mappings, we introduce and study a system of general mixed quasivariational inclusions involving (A,η)-accretive mappings in Banach spaces, and construct a new perturbed iterative algorithm with mixed errors for this system of nonlinear (A,η)-accretive variational inclusions in q-uniformly smooth Banach spaces. Our results improve and generalize the corresponding results of recent works. 相似文献
32.
基于Chord的多集群网格系统资源查找算法改进 总被引:1,自引:0,他引:1
分析了P2P-Grid模式下的多集群网格系统资源查找问题,提出了一种基于Chord的优化资源查找算法P-RN-Tree算法来提高资源定位的效率。通过P-RN-Tree算法,设计并实现了基于Chord的分布式计算资源查找策略。理论分析表明,RN-Tree和P-RN-Tree的高度总是接近lbN,但由于优势集群选择算法的加入,P-RN-Tree平均查找长度要低于RN-Tree。仿真实验结果表明,该算法将进一步减少了资源调度所需的代价,提高了多集群网格系统的性能。 相似文献
33.
Ortwin Feustel 《Nexus Network Journal》2009,11(1):7-21
It is commonly believed that the longitudinal axes of churches extend exactly in an east-west direction. However, thorough
investigations have shown that this is not always correct; rather, both southern and northern deviations of up to about 25°
can occur. The angular deviation between the church axis and true east is called the Holy Alignment. This present study presents the possibility that the nave is oriented towards the direction of the sun-rising point on the
name day of the patron saint of the church. If several saints share the patronage, the Holy Alignment equals the algebraic sum of the angular distances for each saint. The orientation of a nave can be analyzed by means of common
mathematical relations used in geodesy, astronomy and gnomonics. In order to perform such an analysis, it is necessary to
know the history of the patronage of the church; the Gauss-Krüger coordinates of the ground plan; and characteristic astronomical
quantities at the time the church was built. A calculated example with the saints Andrew, James and Philip for the year 980
illustrates the analysis.
An appendix deals with the influence of atmospheric refraction on the apparent altitude of the sun near the horizon. 相似文献
34.
In this paper, we present an analysis and synthesis approach for guaranteeing that the phase of a single-input, single-output closed-loop transfer function is contained in the interval [−α,α] for a given α>0 at all frequencies. Specifically, we first derive a sufficient condition involving a frequency domain inequality for guaranteeing a given phase constraint. Next, we use the Kalman–Yakubovich–Popov theorem to derive an equivalent time domain condition. In the case where , we show that frequency and time domain sufficient conditions specialize to the positivity theorem. Furthermore, using linear matrix inequalities, we develop a controller synthesis approach for guaranteeing a phase constraint on the closed-loop transfer function. Finally, we extend this synthesis approach to address mixed gain and phase constraints on the closed-loop transfer function. 相似文献
35.
A novel optimal Finite Word Length (FWL) controller design is proposed in the framework of μ theory. A computationally tractable close-loop stability measure with FWL implementation considerations of the controller is derived based on the μ theory, and the optimal FWL controller realizations are obtained by solving the resulting optimal FWL realization problem using linear matrix inequality techniques. 相似文献
36.
在机房管理中,多种客观原因常会造成IP地址冲突或计算机重名,在标签纸污损的情况下,学生要对号入座找机器时会显得非常困难。把IP地址及计算机名直接显示在桌面上是解决此问题的有效方法。通过API函数直接实时读取IP地址及计算机名的数据,并把该数据生成图像作为桌面墙纸,从而实现IP地址及计算机名实时显示于桌面的目的。 相似文献
37.
本文着重分析了社交网站常见的法律问题,并通过比较研究各国的做法,试图总结出我国加强社交网站管理的监管措施。 相似文献
38.
An efficient table lookup decoding algorithm (TLDA) is presented to decode up to five possible errors in a binary systematic (47, 24, 11) quadratic residue (QR) code. The main idea of the TLDA is based on the weight of syndrome, the syndrome decoder together with a reduced-size lookup table (RSLT), and the shift-search method given by Reed et al. Thus, the size of the lookup table and computational complexity in a finite field can be significantly reduced. The memory size of the proposed condensed lookup table (CLT) consists of only 36.6 Kbytes and is only about 0.24% of the full lookup table (FLT) and 3.2% of the lookup up table given by Chen et al., respectively. These facts lead to significant reduction of computational time and the decoding complexity. A simulation result shows that the decoding speed of the proposed TLDA is much faster than all existing decoding algorithms. Moreover, it can be extended to decode all QR codes, including the class of the cyclic codes when the code length is moderate. The CLT makes this new decoding algorithm suitable for hardware or firmware implementations. 相似文献
39.
40.
An obnoxious facility is to be located inside a polygonal region of the plane, maximizing the sum of the k smallest weighted Euclidean distances to n given points, each protected by some polygonal forbidden region. For the unweighted case and k fixed an O(n2logn) time algorithm is presented. For the weighted case a thorough study of the relevant structure of the multiplicatively weighted order-k-Voronoi diagram leads to the design of an O(kn3+n3logn) time algorithm for finding an optimal solution to the anti-t-centrum problem for every t=1,…,k, simultaneously. 相似文献