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91.
设g和f分别是定义在图G的顶点集合V(G)上的整数值函数且对每一个x∈V(G)有2≤g(x)≤f(x).证明了若G是(mg+m-1,mf-m+1)—图,则对G中任意一个给定的有m条边的子图H,G有一个(g,f)—因子分解与H正交. 相似文献
92.
Sentiment-oriented contextual advertising 总被引:2,自引:2,他引:0
Web advertising (Online advertising), a form of advertising that uses the World Wide Web to attract customers, has become
one of the world’s most important marketing channels. This paper addresses the mechanism of Content-based advertising (Contextual advertising), which refers to the assignment of relevant ads to a generic web page, e.g., a blog post. As blogs become a platform for
expressing personal opinion, they naturally contain various kinds of expressions, including both facts and comments of both
a positive and negative nature. Besides, in line with the major tenet of Web 2.0 (i.e., user-centric), we believe that the web-site owners would be willing to be in charge of the ads which are positively related to their contents.
Hence, in this paper, we propose the utilization of sentiment detection to improve Web-based contextual advertising. The proposed
sentiment-oriented contextual advertising (SOCA) framework aims to combine contextual advertising matching with sentiment
analysis to select ads that are related to the positive (and neutral) aspects of a blog and rank them according to their relevance.
We experimentally validate our approach using a set of data that includes both real ads and actual blog pages. The results
indicate that our proposed method can effectively identify those ads that are positively correlated with the given blog pages. 相似文献
93.
Xin Ma Xinlong Xu Zheng Zheng Kun Wang Yalin Su Jiangfeng Fan Rui Zhang Lusheng Song Zhiyou Wang Jinsong Zhu 《Sensors and actuators. A, Physical》2010,157(1):9-14
An electro-optically modulated intensity interrogation method based on tunable waveguide coupled surface plasmon resonance sensors has been proposed. It has been theoretically and experimentally demonstrated that the proposed scheme can enable sensitive measurement of measurand variations. By modulating the refractive index in the waveguide layer, this interrogation method yields modulated signal whose amplitude is related to measurand's refractive index. This amplitude modulated signal offers a higher signal to noise ratio and eliminates additive noise in the sensor system. A preliminary investigation using saline buffers with different NaCl concentrations shows a resolution of 2.3 × 10?6 refractive index unit by our approach. Resolution can be controlled by the amplitude of the applied modulation voltage and can be further enhanced by optimizing the device structure or improving the electro-optical (E-O) coefficient of the E-O material. This approach is simple, stable, and promising for low-cost or multi-channel SPR biosensor applications. 相似文献
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96.
一种实时可靠的移动无线传感器网络贪婪地理路由协议 总被引:2,自引:0,他引:2
随着定位装置和定位算法的成熟,基于地理位置信息的贪婪地理路由协议受到广泛的关注与研究.但是,在移动无线传感器网络贪婪地理路由协议中,周期性信标交换条件下采用贪婪转发策略会引起通信暂盲现象,造成数据的丢失.基于右手法则的面遍历算法,对路由空洞的形状不能进行感知,数据转发具有很大的盲目性,转发路径有时比最优路径长很多,造成数据传输时延的增加.针对上述问题提出一种实时可靠的QoS贪婪地理路由协议,该协议通过自适应信标交换算法、基于过渡带思想的贪婪转发策略和基于路标迭代提取和剔除的自适应空洞处理算法,使得数据分组能够实时可靠地传输.NS-2仿真结果表明该协议在不增加控制开销的情况下,能够有效减缓通信暂盲现象,高效地处理路由空洞问题,大大提高协议的实时性和可靠性,可应用于对实时性和可靠性有一定要求的大规模移动无线传感网络. 相似文献
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Jianjun Lei Cuicui Zhang Min Wu Lei You Kefeng Fan Chunping Hou 《Multimedia Tools and Applications》2017,76(6):7661-7676
Large holes are unavoidably generated in depth image based rendering (DIBR) using a single color image and its associated depth map. Such holes are mainly caused by disocclusion, which occurs around the sharp depth discontinuities in the depth map. We propose a divide-and-conquer hole-filling method which refines the background depth pixels around the sharp depth discontinuities to address the disocclusion problem. Firstly, the disocclusion region is detected according to the degree of depth discontinuity, and the target area is marked as a binary mask. Then, the depth pixels located in the target area are modified by a linear interpolation process, whose pixel values decrease from the foreground depth value to the background depth value. Finally, in order to remove the isolated depth pixels, median filtering is adopted to refine the depth map. In these ways, disocclusion regions in the synthesized view are divided into several small holes after DIBR, and are easily filled by image inpainting. Experimental results demonstrate that the proposed method can effectively improve the quality of the synthesized view subjectively and objectively. 相似文献
100.
对信息需求的准确分析是建立设计管理系统的基础。传统的分析方法从过程与人,过程与信息的角度出发综合分析整个机构的信息需求,但是,这种方法没有示识产生和使用信息的范围。为此,;补充分析了信息的机构和项目属性,并通过建立三维组织机构模型;机械、人员和任务模型,有效控制基本的信息存取。 相似文献