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11.
针对网络流量预测模型存在预测稳定性不好、精度较低等问题,提出一种改进布谷鸟搜索算法优化支持向量机的网络流量预测模型(GCS.SVM)。将网络流量时间序列进行重构,采用改进布谷鸟搜索算法优化支持向量机参数,使用这组最优参数建立网络流量预测模型。仿真结果表明,GCS—SVM模型对网络流量预测是有效可行的。 相似文献
12.
Jinhui HuNikolaos V. Boulgouris 《Pattern recognition letters》2011,32(14):1814-1821
We present a method for the recognition of human activities. The proposed approach is based on the construction of a set of templates for each activity as well as on the measurement of the motion in each activity. Templates are designed so that they capture the structural and motion information that is most discriminative among activities. The direct motion measurements capture the amount of translational motion in each activity. The two features are fused at the recognition stage. Recognition is achieved in two steps by calculating the similarity between the templates and motion features of the test and reference activities. The proposed methodology is experimentally assessed and is shown to yield excellent performance. 相似文献
13.
Video Annotation Based on Kernel Linear Neighborhood Propagation 总被引:1,自引:0,他引:1
Jinhui Tang Xian-Sheng Hua Guo-Jun Qi Yan Song Xiuqing Wu 《Multimedia, IEEE Transactions on》2008,10(4):620-628
The insufficiency of labeled training data for representing the distribution of the entire dataset is a major obstacle in automatic semantic annotation of large-scale video database. Semi-supervised learning algorithms, which attempt to learn from both labeled and unlabeled data, are promising to solve this problem. In this paper, a novel graph-based semi-supervised learning method named kernel linear neighborhood propagation (KLNP) is proposed and applied to video annotation. This approach combines the consistency assumption, which is the basic assumption in semi-supervised learning, and the local linear embedding (LLE) method in a nonlinear kernel-mapped space. KLNP improves a recently proposed method linear neighborhood propagation (LNP) by tackling the limitation of its local linear assumption on the distribution of semantics. Experiments conducted on the TRECVID data set demonstrate that this approach outperforms other popular graph-based semi-supervised learning methods for video semantic annotation. 相似文献
14.
We present an approach for animating cracks and fractures in cartoon style. In our method we take a 2D hand-drawn object as input and then construct a 2.5D model of the object in order to approximate the object volume. Next, we generate the Voronoi textures on the 2.5D object model for visual abstraction of cartoon cracks. Further, cracking gaps on the Voronoi textures are widened progressively until Voronoi cells split apart and finally fall onto ground according to simplified physical rules. With minimum user intervention, our model is able to generate cartoon cracks and fractures animations procedurally, as demonstrated by examples given in the paper. 相似文献
15.
Approaches to large-scale urban modeling 总被引:5,自引:0,他引:5
Large-scale urban modeling technologies use a variety of sensors and data acquisition techniques. The authors categorize current approaches and describe their advantages and disadvantages. Their survey examines current research with respect to several performance criteria including data acquisition sources, user interaction level, geometric fidelity, model completeness, and intended applications. Although modeling systems vary with respect to these criteria, data acquisition strongly influences model characteristics and usefulness. We therefore cluster the methods into those based on photogrammetry, active sensors, and hybrid sensor systems. 相似文献
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基于CORBA的三层结构管理信息系统的原理及实现 总被引:4,自引:0,他引:4
研究了基于CORBA的实现管理信息系统的新方法,并对其实现方法、体系结构和关键技术进行了探讨。 相似文献
18.
针对传统的自动控制系统性能指标的测量方法中存在的测量过程复杂,手工操作带来的测量结果误差大等不足,本文提出一种新的基于数字化测量的控制系统性能指标测量方法,实验证明,该方法可有效降低测量过程的复杂度和主观因素,提高测量数据的精确度. 相似文献
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