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51.
YouTube (owned by Google Inc.) is arguably among most popular social media platforms used by millions across the globe. It provides an ever-growing, unique and rich source of content which presents new opportunities and challenges for information discovery and analysis. It is pertinent to explore and understand a topic via YouTube content to discover interesting information about public opinions and sentiments. This paper presents an integrated framework to facilitate the acquisition, storage, management, processing, and visualization of relevant content with the objective to assist in such analysis. It not only collects a significant portion of content, relevant to a given topic, in short time but also offers tools for visual exploratory analysis such as; (i) temporal evolution, (ii) vocabulary network, (iii) authors relative popularity and influence (iv) categories and (v) user communities and influencers. The utility and effectiveness is demonstrated through content analysis of a famous YouTube entertainment topic, the “Gangnam Style”. 相似文献
52.
This paper proposes a novel technique for texture image retrieval based on tetrolet transforms. Tetrolets provide fine texture information due to its different way of analysis. Tetrominoes are applied at each decomposition level of an image and best combination of tetrominoes is selected, which better shows the geometry of an image at each level. All three high pass components of the decomposed image at each level are used as input values for feature extraction. A feature vector is created by taking standard deviation in combination with energy at each subband. Retrieval performance in terms of accuracy is tested on group of texture images taken from benchmark databases: Brodatz and VisTex. Experimental results indicate that the proposed method achieves 78.80% retrieval accuracy on group of texture images D1 (taken from Brodatz), 84.41% on group D2 (taken from VisTex) and 77.41% on rotated texture image group D3 (rotated images from Brodatz). 相似文献
53.
Relevance feedback (RF) is an effective approach to bridge the gap between low-level visual features and high-level semantic meanings in content-based image retrieval (CBIR). The support vector machine (SVM) based RF mechanisms have been used in different fields of image retrieval, but they often treat all positive and negative feedback samples equally, which will inevitably degrade the effectiveness of SVM-based RF approaches for CBIR. In fact, positive and negative feedback samples, different positive feedback samples, and different negative feedback samples all always have distinct properties. Moreover, each feedback interaction process is usually tedious and time-consuming because of complex visual features, so if too many times of iteration of feedback are asked, users may be impatient to interact with the CBIR system. To overcome the above limitations, we propose a new SVM-based RF approach using probabilistic feature and weighted kernel function in this paper. Firstly, the probabilistic features of each image are extracted by using principal components analysis (PCA) and the adapted Gaussian mixture models (AGMM) based dimension reduction, and the similarity is computed by employing Kullback–Leibler divergence. Secondly, the positive feedback samples and negative feedback samples are marked, and all feedback samples’ weight values are computed by utilizing the samples-based Relief feature weighting. Finally, the SVM kernel function is modified dynamically according to the feedback samples’ weight values. Extensive simulations on large databases show that the proposed algorithm is significantly more effective than the state-of-the-art approaches. 相似文献
54.
目的 传统的手绘图像检索方法主要集中在检索相同类别的图像,忽略了手绘图像的细粒度特征。对此,提出了一种新的结合细粒度特征与深度卷积网络的手绘图像检索方法,既注重通过深度跨域实现整体匹配,也实现细粒度细节匹配。方法 首先构建多通道混合卷积神经网络,对手绘图像和自然图像分别进行不同的处理;其次通过在网络中加入注意力模型来获取细粒度特征;最后将粗细特征融合,进行相似性度量,得到检索结果。结果 在不同的数据库上进行实验,与传统的尺度不变特征(SIFT)、方向梯度直方图(HOG)和深度手绘模型Deep SaN(sketch-a-net)、Deep 3DS(sketch)、Deep TSN(triplet sketch net)等5种基准方法进行比较,选取了Top-1和Top-10,在鞋子数据集上,本文方法Top-1正确率提升了12%,在椅子数据集上,本文方法Top-1正确率提升了11%,Top-10提升了3%,与传统的手绘检索方法相比,本文方法得到了更高的准确率。在实验中,本文方法通过手绘图像能在第1幅检索出绝大多数的目标图像,达到了实例级别手绘检索的目的。结论 提出了一种新的手绘图像检索方法,为手绘图像和自然图像的跨域检索提供了一种新思路,进行实例级别的手绘检索,与原有的方法相比,检索精度得到明显提升,证明了本文方法的可行性。 相似文献
55.
《国际互联网参考资料服务季刊》2013,18(1):89-103
Abstract The convergence of computing, communications, and traditional educational technologies enables teaching faculty and librarians to discuss, plan, create, and implement fundamentally unique strategies for providing access to people, information, and the teaching/learning process. A tripartite strategy for achieving these goals is presented. The three critical areas are: (1) Content (how to put together search strategies, look for information, process it, sift it, and organize it); (2) Process (how to use the technology to maximum benefit); and (3) Lobbying (in the areas of information policy, financial resources, and technological infrastructure). An action plan is proposed to provide both inspiration and guidance to help accomplish these goals. 相似文献
56.
D.M. Spracklen 《成像科学杂志》2013,61(4):220-227
Emulsions prepared with an inert gelatin have been sensitized with sodium thiosulphate labelled with radioactive 35S. An analytical technique similar to that used by Frieser and Ranz1 has been used to measure the amounts of silver sulphide formed. The breakdown of thiosulphate has been shown to follow first order reaction kinetics at a rate proportional to the free silver ion concentration in the emulsion to the power of 0.8. 相似文献
57.
Data fusion in information retrieval has been investigated by many researchers and a number of data fusion methods have been proposed. However, problems such as why data fusion can increase effectiveness and favorable conditions for the use of data fusion methods are poorly resolved at best. In this paper, we formally describe data fusion under a geometric framework, in which each component result returned from an information retrieval system for a given query is represented as a point in a multi-dimensional space. The Euclidean distance is the measure by which the effectiveness and similarity of search results are judged. This allows us to explain all component results and fused results using geometrical principles. In such a framework, score-based data fusion becomes a deterministic problem. Several interesting features of the centroid-based data fusion method and the linear combination method are discussed. Nevertheless, in retrieval evaluation, ranking-based measures are the most popular. Therefore, this paper investigates the relation and correlation between the Euclidean distance and several typical ranking-based measures. We indeed find that a very strong correlation exists between these. It means that the theorems and observations obtained using the Euclidean distance remain valid when ranking-based measures are used. The proposed framework enables us to have a better understanding of score-based data fusion and use score-based data fusion methods more precisely and effectively in various ways. 相似文献
58.
59.
自动化立体仓库是一种典型的机电一体化设备,对于机电一体化专业学生理解和掌握机电一体化系统设计及维护有着极大的帮助.介绍了基于PLC的自动化立体仓库实验系统的研制,该系统由机械本体、电气系统、PLC控制系统以及组态监控系统构成.装置研发成功后,已经在课程教学、实训以及毕业设计等环节得到了应用,取得了预期的效果. 相似文献
60.
以自动化立体仓库系统的硬件组成为出发点,重点对其控制系统从硬件设计和软件设计两方面进行了深入研究.通过PROFIBUS现场总线将系统的监控机、上位机以及下位机连接成-个有机整体,同时应用工控组态软件组态王Kingview对系统进行监控,达到了远程实时监控和管理的目的.现场调试结果表明,该系统自动化程度较高,操作方便,工... 相似文献