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81.
无线传感器网络在电能信息采集中的应用 总被引:1,自引:0,他引:1
在介绍电力线载波、RS-485、无线传感网络系统特点的基础上,提出了基于无线传感器网络技术的远程无线用电信息集抄的实现方案。详细讨论了硬件设计、软件设计和网络节点的功耗问题。方案具有高可靠、低成本、易维护、覆盖面积大等特点。系统可以实现自动组网、数据传输,达到无需现场干预实现电能信息管理系统跟电能表之间的信息交互。 相似文献
82.
针对图像的Legendre正交矩计算量大和矩值求解过程中存在离散近似误差等问题,提出一种新的高精度快速计算图像Legendre矩方法.文中首先提出一种最大块优先分块策略,然后在此基础上,根据图像像素灰度值的取值特征将图像进行分块表示,以每个图像块为单位计算图像的Legendre矩.实验结果表明,与现有的快速算法相比,文中方法在保证矩值高精确的前提下,有效地减少了算术运算的次数,降低了计算复杂度,具有较快的计算速度. 相似文献
83.
We present an algorithm for computing a Smith form with multipliers of a regular matrix polynomial over a field. This algorithm differs from previous ones in that it computes a local Smith form for each irreducible factor in the determinant separately and then combines them into a global Smith form, whereas other algorithms apply a sequence of unimodular row and column operations to the original matrix. The performance of the algorithm in exact arithmetic is reported for several test cases. 相似文献
84.
fKenzo (=friendly Kenzo) is a graphical user interface providing a user-friendly front-end for the Kenzo system, a Common Lisp program devoted to Algebraic Topology. The fKenzo system provides the user interface itself, an XML intermediary generator-translator and, finally the Kenzo kernel. We describe in this paper the main points of fKenzo, and we explain also the advantages and limitations of fKenzo with respect to Kenzo itself. The text is separated into two parts, trying to cover both the user and the developer perspectives. 相似文献
85.
A new hybrid differential evolution algorithm, in which an ant system is used to select the optimal base vector of mutation operation, named the ant system differential evolution (ASDE), is proposed. In ASDE, each dimension in the feasible solution space is divided into several subspaces evenly, and each subspace is marked with the same initial intensity of pheromone trails. The probability of choosing an individual as the base vector is influenced by the visibility and pheromone quantity of the individual. The trail of the selected base vector’s location subspaces will be reinforced with some pheromones, when the offspring is better than its parent. The experimental results show that the ASDE generally outperforms the other differential evolution algorithms for nine benchmark functions. Furthermore, the ASDE is applied to develop the global kinetic model for SO2 oxidation on the Cs-Rb-V catalyst, and satisfactory results are obtained. 相似文献
86.
Antonio Fernández-CaballeroAuthor Vitae María T. LópezAuthor Vitae Enrique J. CarmonaAuthor VitaeAna E. DelgadoAuthor Vitae 《Neurocomputing》2011,74(8):1175-1181
Certainly, one of the prominent ideas of Professor José Mira was that it is absolutely mandatory to specify the mechanisms and/or processes underlying each task and inference mentioned in an architecture in order to make operational that architecture. The conjecture of the last fifteen years of joint research has been that any bottom-up organization may be made operational using two biologically inspired methods called “algorithmic lateral inhibition”, a generalization of lateral inhibition anatomical circuits, and “accumulative computation”, a working memory related to the temporal evolution of the membrane potential. This paper is dedicated to the computational formulation of both methods. Finally, all of the works of our group related to this methodological approximation are mentioned and summarized, showing that all of them support the validity of this approximation. 相似文献
87.
Xiao-Juan Luo Triantafyllos Stylianopoulos Victor H. Barocas Mark S. Shephard 《Engineering with Computers》2009,25(1):87-95
The mechanical function of soft collagenous tissues is inherently multiscale, with the tissue dimension being in the centimeter
length scale and the underlying collagen network being in the micrometer length scale. This paper uses a volume averaging
multiscale model to predict the collagen gel mechanics. The model is simulated using a multiscale component toolkit that is
capable of dealing with any 3D geometries. Each scale in the multiscale model is treated as an independent component that
exchanges the deformation and average stress information through a scale-linking operator. An arterial bifurcation was simulated
using the multiscale model, and the results demonstrated that the mechanical response of the soft tissues is strongly sensitive
to the network orientation and fiber-to-fiber interactions. 相似文献
88.
Existing Global Data Computation (GDC) protocols for asynchronous systems are round-based algorithms designed for fully connected networks. In this paper, we discuss GDC in asynchronous chordal rings, a non-fully connected network. The virtual links approach to solve the consensus problem may be applied to GDC for non-fully connected networks, but it incurs high message overhead. To reduce the overhead, we propose a new non-round-based GDC protocol for asynchronous chordal rings with perfect failure detectors. The main advantage of the protocol is that there is no notion of rounds. Every process creates two messages initially, with one message traversing in a clockwise direction and visiting each and every process in the chordal ring. The second message traverses in a counterclockwise direction. When there is direct connection between two processes, a message is sent directly. Otherwise, the message is sent via virtual links. When the two messages return, the process decides according to the information maintained by the two messages. The perfect failure detector of a process need only detect the crash of neighboring processes, and the crash information is disseminated to all other processes. Analysis and comparison with two virtual links approaches show that our protocol reduces message complexity significantly. 相似文献
89.
Given a list of n items and a function defined over sub-lists, we study the space required for computing the function for arbitrary sub-lists in constant time.For the function mode we improve the previously known space bound O(n2/logn) to O(n2loglogn/log2n) words.For median the space bound is improved to O(n2loglog2n/log2n) words from O(n2⋅log(k)n/logn), where k is an arbitrary constant and log(k) is the iterated logarithm. 相似文献
90.
Dong-Xia Chang Author Vitae Xian-Da Zhang Author Vitae Author Vitae 《Pattern recognition》2009,42(7):1210-1987
In this paper, a new clustering algorithm based on genetic algorithm (GA) with gene rearrangement (GAGR) is proposed, which in application may effectively remove the degeneracy for the purpose of a more efficient search. A new crossover operator that exploits a measure of similarity between chromosomes in a population is also presented. Adaptive probabilities of crossover and mutation are employed to prevent the convergence of the GAGR to a local optimum. Using the real-world data sets, we compare the performance of our GAGR clustering algorithm with K-means algorithm and other GA methods. An application of the GAGR clustering algorithm in unsupervised classification of multispectral remote sensing images is also provided. Experiment results demonstrate that the GAGR clustering algorithm has high performance, effectiveness and flexibility. 相似文献