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991.
Xiang-Bin Shi Xue Wang Jing Bi Fang Liu Dan Yang Xian-Yan Liu 《Multimedia Tools and Applications》2009,45(1-3):247-261
Considering player entity’s motion regularity into DR (Dead Reckoning) algorithm can improve its prediction accuracy in MMOG (Massively Multiplayer Online Games), a novel DR algorithm was proposed to solve this problem in this paper. First the artificial potential field model of player entities is created, and then the acceleration of player entities is weighted with the acceleration produced by the potential field force and the acceleration reckoned by the traditional DR algorithm. In order to calculate the weight, Q-Learning algorithm is used. The experiments show that the method can improve prediction accuracy and reduce the network traffic. 相似文献
992.
Kai Wang Jufeng Yang Guangshun Shi Qingren Wang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(12):1153-1161
The generalization problem of an artificial neural network (ANN) classifier with unlimited size of training sample, namely
asymptotic optimization in probability, is discussed in this paper. As an improved ANN network model, the pre-edited ANN classifier
shows better practical performance than the standard one. However, it has not been widely applied due to the absence of the
related theoretical support. To further promote its application in practice, the asymptotic optimization of the pre-edited
ANN classifier is studied in this paper. To help study ANN asymptotic optimization in probability, we gives a review of the
previous research works on asymptotic optimization in probability of non-parametric classifier, and grouped the main methods
into four classes: two-step method, one-step method, generalization method and hypothesis method. In this paper, we adopt
generalization/hypothesis mixed method to prove that pre-edited ANN is asymptotically optimal in probability. Furthermore,
a simulation is presented to provide an experimental support for our theoretical work. 相似文献
993.
Image Retargeting Using Mesh Parametrization 总被引:3,自引:0,他引:3
Yanwen Guo Feng Liu Jian Shi Zhi-Hua Zhou Gleicher M. 《Multimedia, IEEE Transactions on》2009,11(5):856-867
Image retargeting aims to adapt images to displays of small sizes and different aspect ratios. Effective retargeting requires emphasizing the important content while retaining surrounding context with minimal visual distortion. In this paper, we present such an effective image retargeting method using saliency-based mesh parametrization. Our method first constructs a mesh image representation that is consistent with the underlying image structures. Such a mesh representation enables easy preservation of image structures during retargeting since it captures underlying image structures. Based on this mesh representation, we formulate the problem of retargeting an image to a desired size as a constrained image mesh parametrization problem that aims at finding a homomorphous target mesh with desired size. Specifically, to emphasize salient objects and minimize visual distortion, we associate image saliency into the image mesh and regard image structure as constraints for mesh parametrization. Through a stretch-based mesh parametrization process we obtain the homomorphous target mesh, which is then used to render the target image by texture mapping. The effectiveness of our algorithm is demonstrated by experiments. 相似文献
994.
基于ART2神经网络的车辆感应波形识别的方法 总被引:1,自引:0,他引:1
在智能交通系统中,无论是在交通监控领域还是在不停车收费系统方面,对车辆进行自动分类都十分重要;环形线圈车辆检测器以其良好的适应性、稳定性和高效性在车辆监测方面得到了广泛的应用,同时利用同类型或同种车辆经过环形线圈产生轮廓相似的电磁感应波形这一特点也可以进行车型识别;对波形进行预处理,以波形轮廓的抽样、量化值作为特征向量,将特征向量作为ART2神经网络的输入向量,经ART2神经网络的自动聚类最终实现车辆感应波形的聚类与识别。 相似文献
995.
利用TIA(时序分析仪)或其它模拟方法来测量光盘的抖晃存在成本高、灵活性差、稳定性低等不足,而在实际的光盘生产测试过程中,更需要一种升级扩展方便、性价比高的测试设备。在粗糙脉宽检测方法的基础上,引入时间放大电路,成功地设计出一套以FPGA为核心,基于PCI Express总线的抖晃测试系统;实验表明,该系统具有结构简单、精度高、设计灵活、成本低等特点,在光盘测试和抖晃特性研究方面具有较好的应用价值和一定的市场前景。 相似文献
996.
嵌入式Linux中SDIO协议无线网络驱动程序的设计和实现 总被引:1,自引:0,他引:1
从嵌入式Linux项目SDIO总线接V1的开发设计需求出发,对嵌入式系统的SDIO总线协议栈进行了分析,讨论了其作为一个通用总线协议栈模块对原来WinCE环境BSQUARE接口的代码移植的可行性,并介绍了包含SDIO总线协议栈模块的无线网络驱动程序的实现方法。 相似文献
997.
Dongling Zhang Yong Shi Yingjie Tian Meihong Zhu 《Frontiers of Computer Science in China》2009,3(2):192-204
An extensive review for the recent developments of multiple criteria linear programming data mining models is provided in
this paper. These researches, which include classification and regression methods, are introduced in a systematic way. Some
applications of these methods to real-world problems are also involved in this paper. This paper is a summary and reference
of multiple criteria linear programming methods that might be helpful for researchers and applications in data mining. 相似文献
998.
在网络层次上进行区域交通信号控制、交通分配和路径诱导是缓解交通堵塞的有效途径之一。为进一步提高城市交通网络分类检测的准确性,将支持向量机(Support Vector Machine)应用于交通事件的模式分类研究。通过提出一种基于多类别支持向量机的交通模式分类方法,设计了适合该检测系统的网络结构。仿真结果表明:相对于其他算法,城市交通网络的状态可分为数量有限且不同类型的模式,并且这些模式不断重复出现,当系统识别出网络处于某种模式时,就可参照事先确定的优化参数及策略进行交通控制和诱导,以缓解交通拥塞,提高交通系统的运行效率。该网络结构对于小样本数据具有检测率高、误报率低的优点,完全适用于城市交通的模式分类,同时也存在不足之处,指出了今后进一步研究的方向。 相似文献
999.
Shi JF Wang CJ Berryman F Hart W 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2008,222(5):657-667
In this paper fixed- and mobile-bearing implants were simulated using a multibody dynamic model and a finite element model to investigate the contact pressure distribution in the ultra high molecular weight polyethylene tibial bearing component. The thickness of polyethylene varied from 6.8 to 12.3 mm and the polyethylene was modelled as a non-linear material. It was found that the contact pressure on the polyethylene decreased in the fixed-bearing implant when the thickness of polyethylene increased from 6.8 to 8 and 9.6 mm, but there was little further decrease in pressure with the increase of polyethylene thickness from 9.6 to 11.0 and 12.3 mm. In the mobile-bearing implant, no increase in contact pressure on the superior surface was found with the increase in the thickness of the polyethylene; however, the contact pressures on the inferior contact surface of the thicker designs were higher than those in the 6.8 mm design. The numerical results obtained in this paper are in good agreement with published experimental test results. Moreover, the paper presents a detailed pressure distribution on the tibial bearing component during a full gait cycle. 相似文献
1000.
将以太网通讯技术和A/D转换器以及传感器相结合,在用VB语言自编程的基础上设计了一种工业状态参数实时测控系统,该系统具有实时监测、实时控制、实时数据处理、数据保存、超限数据报警、历史数据查看以及通讯状态的自诊断等功能,而且操作简单。在GTL合成油装置上试验表明本测控系统具有良好的稳定性和可靠性。 相似文献