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91.
受环境、硬件设备及成本等因素限制,所生产的视频质量低,存在大量冗余噪声,导致局部区域图像模糊不清,无法对目标个体判定或识别。为解决上述问题,构建一种基于变分正则化的低质视频图像二维增强方法。通过采集先验信息,确定噪声去除和质量增强区域,随后使用ROF经典模型和偏微分对原始图像做平滑及去噪处理,并提出前后扩散方程,使方法能够有效抑制背景区域噪声,并对目标个体边缘做锐化处理,利用变分正则化提升视频图像整体分辨率,使其完成图像二维增强。仿真结果表明,所提方法具有控制噪声与加强图像质量双重优势,有效去除、抑制噪声影响,提升目标个体区域强散射点,且方法复杂程度较低,能够实现低质视频图像的均衡优化。 相似文献
92.
为解决煤矿井下瓦斯抽采管网因系统变化导致的抽采效率降低的问题,根据抽采系统各项特性建立了有向图论模型,将瓦斯抽采浓度与混合流量赋值于模型点权参数,将瓦斯管路长度、管径赋值于图论模型边权参数,以O-D对流量概念和管路阻力计算为基础,得到了管网中各管段阻力损失,并确定了优化管段位置及优化方案和参数。对芦岭煤矿8210抽采区域进行优化后,优化管段阻力损失降低了8倍,优化区域抽采纯量提高了1倍以上。 相似文献
93.
该文用“图”这一数学工具,通过定量分析来揭示语言系统中的隐性规律,设计了“赢家通吃”和“赢多输少”两种生成算法,将理想算法“步步竞争、择优而行”的博弈论思路贯彻到非理想状态。两种新算法都较前人有更好的概括能力。赢多输少算法更兼顾了充分概括和适度概括均衡。生成语图后,该设计着重准确率的最小简图和着重覆盖率的最大简图归纳算法,挖掘控制的主流规则、分析语言系统的语言学规律。在最小简图基础上提出控制度公式以评价语言系统。
相似文献
相似文献
94.
活动社交网络(EBSNs)为用户提供了方便的组织、参加和分享社交活动的平台。该文面向EBSNs活动推荐问题,提出了包含活动(Event)、主办方(Sponsor)和用户(User)的ESU图模型,深入揭示了EBSNs的实体及其社交关系。因为用户参加活动受多个因素影响,我们提出了基于ESU图的活动推荐多因素决策模型,包括社交影响力、活动内容、活动地点及活动时间。根据ESU图特点,提出了基于双向重启随机游走算法BD-RWR的实体重要度计算方法。选取真实的EBSNs平台—豆瓣同城验证所提方法的有效性。实验结果表明,该文提出的ESU图模型及融合了多因素的活动推荐模型,与已有最新方法相比,有效地提升了用户参加活动的推荐效果。 相似文献
95.
针对现有图形模糊聚类算法合理性差和抗噪能力弱的问题,提出嵌入对称正则项的图形模糊聚类鲁棒算法。将样本聚类所对应的中立度与拒分度相结合构造对称正则项,嵌入现有图形模糊聚类所对应的目标函数;同时,利用像素邻域所对应的均值信息辅助当前像素聚类并构造了空间信息约束正则项,采用拉格朗日乘子法获得正则化图形模糊聚类鲁棒分割算法。不同噪声干扰图像分割结果表明,所建议的分割算法是有效的,相比现有的鲁棒模糊聚类分割算法具有更强的抑制噪声能力。 相似文献
96.
This paper presents an approach for evaluating collaboration attributes in companies operating in industrial clusters. From the literature review, we identified governance, geographic proximity, and trust as the main collaboration attributes in industrial clusters. For each of them, there is a set of related sub-attributes that composed the evaluation model. For developing the model, we used the graph theoretic approach (GTA), a methodology for multi-attribute assessment that considers interdependencies among elements of a system to provide an overall evaluation. We applied the model to five companies of a furniture cluster. The results showed the model allows for systematizing relationship management because it highlights the collaboration attributes that need to be improved. Furthermore, the application of the model may contribute to encouraging companies to develop collaborative practices. 相似文献
97.
Yong-Fu Zhang 《Inverse Problems in Science & Engineering》2016,24(9):1606-1646
In this paper, a recursion numerical technique is considered to solve the inverse heat conduction problems, with an unknown time-dependent heat source and the Neumann boundary conditions. The numerical solutions of the heat diffusion equations are constructed using the Gaussian radial basis functions. The details of algorithms in the one-dimensional and two-dimensional cases, involving the global or partial initial conditions, are proposed, respectively. The Tikhonov regularization method, with the generalized cross-validation criterion, is used to obtain more stable numerical results, since the linear systems are badly ill-conditioned. Moreover, we propose some results of the condition number estimates to a class of positive define matrices constructed by the Gaussian radial basis functions. Some numerical experiments are given to show that the presented schemes are favourably accurate and effective. 相似文献
98.
Electrical resistance tomography (ERT) reconstructs the conductivity distribution from the boundary changes of electrical measurements. The inverse problem of ERT is seriously ill-posed where regularization methods are needed to treat this ill-posedness. A proper choice of regularization parameter which controls the degree of smoothing is very important for these regularization methods. Although have been a variety of methods, such as L-curve method, to choose a reasonable parameter for the problem, these methods usually result in a scalar parameter which cannot distinctly express the spatial characteristic of the conductivity distribution. So a spatially adaptive regularization parameter choice method is proposed for regularizing the inverse problem of ERT based on Tikhonov regularization. Since large regularization parameters can stabilize and smoothen the solution, while small regularization parameters can approximate and sharpen the solution, the proposed method adaptively updates the regularization parameters during the iteration process and provides spatially varying parameter for each pixel of the reconstructed image. When the iteration is stopped, large regularization parameters for the smooth background region and small regularization parameters for the object region can be obtained. The method is discussed using simulated data for some typical conductivity distributions, and further applied to the analysis of real measurement data acquiring from the practical system. The results demonstrate that flexible regularization parameter vectors can be achieved for different distributions and the strength of regularization is adaptively provided for different regions in a specific distribution. The adaptive method achieves an efficient and reliable regularization solution and has outstanding performance in noise immunity especially in smooth background regions. 相似文献
99.
To detect copy-paste tampering, an im-proved SIFT (Scale invariant feature transform)-based al-gorithm was proposed. Maximum angle is defined and a maximum angle-based marked graph is constructed. The m arked graph feature vector is provided to each SIFT key point via discrete polar coordinate transformation. Key points are matched to detect the copy-paste tamper-ing regions. The experimental results show that the pro-posed algorithm can effectively identify and detect the ro-tated or scaled copy-paste regions, and in comparison with the methods reported previously, it is resistant to post-processing, such as blurring, Gaussian white noise and JPEG recompression. The proposed algorithm performs better than the existing algorithm to dealing with scaling transformation. 相似文献
100.
《Expert systems with applications》2014,41(2):535-543
Most existing research on applying the matrix factorization approaches to query-focused multi-document summarization (Q-MDS) explores either soft/hard clustering or low rank approximation methods. We employ a different kind of matrix factorization method, namely weighted archetypal analysis (wAA) to Q-MDS. In query-focused summarization, given a graph representation of a set of sentences weighted by similarity to the given query, positively and/or negatively salient sentences are values on the weighted data set boundary. We choose to use wAA to compute these extreme values, archetypes, and hence to estimate the importance of sentences in target documents set. We investigate the impact of using the multi-element graph model for query focused summarization via wAA. We conducted experiments on the data of document understanding conference (DUC) 2005 and 2006. Experimental results evidence the improvement of the proposed approach over other closely related methods and many of state-of-the-art systems. 相似文献