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41.
We introduce a machine learning-based classifier that identifies free radio channels for cognitive radio. The architecture is designed for nanoscale implementation, under nanoscale implementation constraints; we do not describe all physical details but believe future physical implementation to be feasible. The system uses analog computation and consists of cyclostationary feature extraction and a radial basis function network for classification. We describe a model for nanoscale faults in the system, and simulate experimental performance and fault tolerance in recognizing WLAN signals, under different levels of noise and computational errors. The system performs well under expected non-ideal manufacturing and operating conditions.  相似文献   
42.
This paper presents a systematic approach for decreasing conservativeness in stability analysis and control design for Takagi-Sugeno (TS) systems. This approach is based on the idea of multiple Lyapunov functions together with simple techniques for introducing slack matrices. Unlike some previous approaches based on multiple Lyapunov functions, both the stability and the stabilization conditions are written as linear matrix inequality (LMI) problems. The proposed approach reduces the number of inequalities and guarantees extra degrees of freedom to the LMI problems. Numeric examples illustrate the effectiveness of this method.  相似文献   
43.
44.
This paper addresses the stability issue of discrete-time switched systems with guaranteed dwell-time. The approach of switched homogeneous Lyapunov function of higher order is formally proposed. By means of this approach, a necessary and sufficient condition is established to check the exponential stability of the considered system. With the observation that switching signal is actually arbitrary if the dwell time is one sample time, a necessary and sufficient condition is also presented to verify the exponential stability of switched systems under arbitrary switching signals. Using the augmented argument, a necessary and sufficient exponential stability criterion is given for discrete-time switched systems with delays. A numerical example is provided to show the advantages of the theoretical results.  相似文献   
45.
研究了基于平行截面上两多边形轮廓重构的基本问题,给出了利用体积最大化作为度量标准来求得一个"较好"并且合法的重构的目标函数,然后得出:其中一个多边形轮廓在其所在的截面上沿着法向平移、在截面内平移和在截面内等比例缩放都不影响最大化体积后的结果。该结论对于三维实体的可视化和几何造型领域具有重要的实用价值。  相似文献   
46.
Matlab和C++接口中函数注册的实现   总被引:3,自引:0,他引:3  
函数注册在Matlab和C 接口中起着重要的作用。在介绍函数注册作用的基础上 ,详细分析了函数注册的过程及应当注意的问题 ,并给出了一种实现函数注册的最简单的方法。用实例展示了函数注册的具体实现过程。  相似文献   
47.
A new numerical scheme for computing balancing coordinate transformations in linear systems theory is presented. The method is closely related to the Jacobi method for diagonalizing symmetric matrices. Here the minimization of the sum of traces of the Gramians by orthogonal and nonorthogonal Jacobi-type rotations is considered. The algorithm is shown to be globally convergent to a balancing transformation that arranges the Hankel singular values in a prescribed ordering. Local quadratic convergence of the algorithm is shown.  相似文献   
48.
This study presents a novel means of resolving multiple objective goal programming (GP) problems with quasi-convex linear penalty functions. The proposed method initially expresses a quasi-convex function by the maximum operator of two convex functions, then solves it via a linear programming technique. The proposed method does not contain any zero–one variables; nor does it require dividing the multi-objective quasi-convex GP problem into large sub-problems as in conventional methods. Some illustrative examples are provided.  相似文献   
49.
To deal with the planarization problem widely used in many applications including routing very-large-scale integration (VLSI) circuits, this paper points out that only when its vertices are arranged in some specific order in a line can a planar graph be embedded on a line without any cross connections or cross edges. Energy function is proposed to meet the need of embedding a graph on a single line and route it correctly. A Hopfield network is designed according to the proposed energy function for such embedding and routing. The advantage of the proposed method is that it not only can detect if a graph is a planar one or not, but also can embed a planar graph or the maximal planar subgraph of a non-planar graph on a single line. In addition, simulated annealing is employed for helping the network to escape from local minima during the running of the Hopfield network. Experiments of the proposed method and its comparison with some existent conventional methods were performed and the results indicate that the proposed method is of great feasibility and effectiveness especially for the planarization problem of large graphs.  相似文献   
50.
完全随机设计的实质是将供试单位随机分组。该文通过对完全随机设计实质的分析,对运用EXCEL进行完全随机试验设计的方法进行了介绍。结果认为只要每一独立供试单位在组间随机排列,始终贯穿随机精神以最大限度地减少系统误差,灵活利用Excel的随机函数如RANDOM、RANDOMBETWEEN等和排序按钮,用任何一种方法都可以快速的进行完全随机试验设计。  相似文献   
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