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991.
992.
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
993.
随着开源运动的不断发展,从数据持久层到业务层再到表现层都涌现了一批优秀的轻量级开源框架。针对轻量级J2EE架构的整体设计和各个层的具体设计展开研究,综述了各个层中出现的主要框架和设计方案,分别对它们进行了比较分析。 相似文献
994.
MATLAB r2006(7.3)下利用COM组件实现VB.net与MATLAB混合编程的新方法。并用实例介绍了这种方法的具体应用过程。 相似文献
995.
许强 《数字社区&智能家居》2008,(2):664-667
在研究面向方面编程思想的基础上,提出了一种Web应用框架。论述了采用J2EE过滤器实现关注点引擎,通过配置文件实现初始化并在运行时动态组装系统关注点和核心关注点的原理与方法。基于框架设计并实现了毕业论文管理系统,实践表明了框架的正确性与有效性。 相似文献
996.
Kalb J.A. Qiang Guo Xiaoqiang Zhang Yi Li Chornghaur Sow Thompson C.V. 《Journal of microelectromechanical systems》2008,17(5):1094-1103
Phase-change materials have been extensively used for optical data storage in commercial rewritable compact disks and digital video disks. These materials are also widely considered for next-generation phase-change random access memories to replace current Flash memories. We suggest a different application of phase-change materials in optically triggered microactuators. The suggested device consists of a thin film of a phase-change material deposited on a microfabricated cantilever. A laser-induced phase transformation in the film initiates a cantilever deflection since the transformation is accompanied by a large density change. We analyze quantitative criteria for material selection and optimization of device dimensions for the largest possible actuation angles and deflections. The resulting analytical model is both verified numerically and applied experimentally. Furthermore, we show that these cantilevers offer a convenient way to measure film stresses and film strains associated with laser-induced phase transformations. 相似文献
997.
A new criterion of delay-dependent asymptotic stability for Hopfield neural networks with time delay. 总被引:1,自引:0,他引:1
Shaoshuai Mou Huijun Gao James Lam Wenyi Qiang 《Neural Networks, IEEE Transactions on》2008,19(3):532-535
In this brief, the problem of global asymptotic stability for delayed Hopfield neural networks (HNNs) is investigated. A new criterion of asymptotic stability is derived by introducing a new kind of Lyapunov-Krasovskii functional and is formulated in terms of a linear matrix inequality (LMI), which can be readily solved via standard software. This new criterion based on a delay fractioning approach proves to be much less conservative and the conservatism could be notably reduced by thinning the delay fractioning. An example is provided to show the effectiveness and the advantage of the proposed result. 相似文献
998.
Datong Chen Qiang Liu Mingui Sun Jie Yang 《Multimedia, IEEE Transactions on》2008,10(2):268-276
In this paper, we propose an approach for learning appearance models of moving objects directly from compressed video. The appearance of a moving object changes dynamically in video due to varying object poses, lighting conditions, and partial occlusions. Efficiently mining the appearance models of objects is a crucial and challenging technology to support content-based video coding, clustering, indexing, and retrieval at the object level. The proposed approach learns the appearance models of moving objects in the spatial-temporal dimension of video data by taking advantage of the MPEG video compression format. It detects a moving object and recovers the trajectory of each macroblock covered by the object using the motion vector present in the compressed stream. The appearances are then reconstructed in the DCT domain along the object's trajectory, and modeled as a mixture of Gaussians (MoG) using DCT coefficients. We prove that, under certain assumptions, the MoG model learned from the DCT domain can achieve pixel-level accuracy when transformed back to the spatial domain, and has a better band-selectivity compared to the MoG model learned in the spatial domain. We finally cluster the MoG models to merge the appearance models of the same object together for object-level content analysis. 相似文献
999.
1000.