The task of the VAST 2011 Grand Challenge was to investigate potential terrorist activities and their relation to the spread of an epidemic. Three different data sets were provided as part of three Mini Challenges (MC...
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The task of the VAST 2011 Grand Challenge was to investigate potential terrorist activities and their relation to the spread of an epidemic. Three different data sets were provided as part of three Mini Challenges (MCs). MC 1 was about analyzing geo-tagged microblogging (Twitter) messages to characterize the spread of an epidemic. MC 2 required analyzing threats to a computer network using a situational awareness approach. In MC 3 possible criminal and terrorist activities were to be analyzed based on a collection of news articles. To solve the Grand Challenge, insight from each of the individual MCs had to be integrated appropriately.
Documents in rich text corpora often contain multiple facets of information. For example, an article from a medical document collection might consist of multifaceted information about symptoms, treatments, causes, dia...
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Documents in rich text corpora often contain multiple facets of information. For example, an article from a medical document collection might consist of multifaceted information about symptoms, treatments, causes, diagnoses, prognoses, and preventions. Thus, documents in the collection may have different relations across each of these various facets. Topic analysis and exploration for such multi-relational corpora is a challenging visual analytic task. This paper presents Solar Map, a multifaceted visual analytic technique for visually exploring topics in multi-relational data. Solar Map simultaneously visualizes the topic distribution of the underlying entities from one facet together with keyword distributions that convey the semantic definition of each cluster along a secondary facet. Solar Map combines several visual techniques including 1) topic contour clusters and interactive multifaceted keyword topic rings, 2) a global layout optimization algorithm that aligns each topic cluster with its corresponding keywords, and 3) 2) an optimal temporal network segmentation and layout method that renders temporal evolution of clusters. Finally, the paper concludes with two case studies and quantitative user evaluation which show the power of the Solar Map technique.
The literature in educational research has established that monitoring student learning is a crucial component of high quality education. When instructors and students are not in a face-to-face traditional environment...
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The literature in educational research has established that monitoring student learning is a crucial component of high quality education. When instructors and students are not in a face-to-face traditional environment, new forms of student monitoring must be explored. The effective use of CMS requires that instructors been provided with appropriate means of diagnosing problems so that they can take immediate actions to prevent or overcome those situations. The aim of this research is to support the comprehension of the evolution of the semantic content within eLearning environments through uncovering by means of visual representations. Therefore, we have carried out the mining of an eLearning database and represented the more relevant results by depicting them using a visualization based in the tag cloud visual representation. In this paper, we introduce a visual representation, which integrate a wave-graph and a bar-graph into a tag cloud representation to understand the evolution of words.
The Internet, Web 2.0 and Social Networking technologies are enabling citizens to actively participate in "citizen science" projects by contributing data to scientific programs. However, the limited expertis...
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The Internet, Web 2.0 and Social Networking technologies are enabling citizens to actively participate in "citizen science" projects by contributing data to scientific programs. However, the limited expertise of contributors can lead to poor quality or misleading data being submitted. Subsequently, the scientific community often perceive citizen science data as not worthy of being used in serious scientific research. In this paper, we describe how online reputation models can be adapted for citizen science projects to provide a simple and effective mechanism for assessing the reliability of community-generated data. We also describe the reputation aware querying, filtering and visualization services that we have developed that enable users to distinguish between datasets based on the reputation of the source/contributor. The resulting services are evaluated in the context of the Coral Watch project which uses volunteers to collect data on coral reef bleaching.
The Sammon Mapping (SM) has established itself as a valuable tool in dimensionality reduction, manifold learning, exploratory dataanalysis and, particularly, in datavisualization. The SM is capable of projecting hig...
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The Sammon Mapping (SM) has established itself as a valuable tool in dimensionality reduction, manifold learning, exploratory dataanalysis and, particularly, in datavisualization. The SM is capable of projecting high-dimensional data into a low-dimensional space, so that they can be visualized and interpreted. This is accomplished by representing inter-sample dissimilarities in the original space by Euclidean inter-sample distances in the projection space. Recently, Kernel Sammon Mapping (KSM) has been shown to subsume the SM and a few other related extensions to SM. Both of the aforementioned models feature a set of linear weights that are estimated via Iterative Majorization (IM). While IM is significantly faster than other standard gradient-based methods, tackling data sets of larger than moderate sizes becomes a challenging learning task, as IM's convergence significantly slows down with increasing data set cardinality. In this paper we derive two improved training algorithms based on Successive Over-Relaxation (SOR) and Parallel Tangents (PARTAN) acceleration, that, while still being first-order methods, exhibit faster convergence than IM. Both algorithms are relatively easy to understand, straightforward to implement and, performance-wise, are as robust as IM. We also present comparative results that illustrate their computational advantages on a set of benchmark problems.
Twitter currently receives about 190 million tweets (small text-based Web posts) a day, in which people share their comments regarding a wide range of topics. A large number of tweets include opinions about products a...
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Twitter currently receives about 190 million tweets (small text-based Web posts) a day, in which people share their comments regarding a wide range of topics. A large number of tweets include opinions about products and services. However, with Twitter being a relatively new phenomenon, these tweets are underutilized as a source for evaluating customer sentiment. To explore high-volume twitter data, we introduce three novel time-based visual sentiment analysis techniques: (1) topic-based sentiment analysis that extracts, maps, and measures customer opinions; (2) stream analysis that identifies interesting tweets based on their density, negativity, and influence characteristics; and (3) pixel cell-based sentiment calendars and high density geo maps that visualize large volumes of data in a single view. We applied these techniques to a variety of twitter data, (e.g., movies, amusement parks, and hotels) to show their distribution and patterns, and to identify influential opinions.
Area properties of mapping region has important impact on expressive effects of color grading symbol, which is mainly reflected in two aspects: firstly, color's area proportion in mapping region will affect the st...
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ISBN:
(纸本)9781612848495
Area properties of mapping region has important impact on expressive effects of color grading symbol, which is mainly reflected in two aspects: firstly, color's area proportion in mapping region will affect the strength of visual impact from color, which can influence maps' clarity and comfort; secondly, area difference between different classes will affects visual perception caused by original color grading symbols, which can cause visual illusion. Based on China's provincial area model, this paper explores how to recognize the problems caused by area difference, and provide thought of auto-adjustment of traditional color grading symbol. Then the paper realizes the method using Visual C# and Supermap Object to realize a system having the function of the auto - adjustment of the map color.
In the last years, a huge effort has been devoted to the improvement of simulation tools for Vehicular Ad-Hoc Networks (VANETs). However, one gap still needs to be filled: tools supporting the precise comprehension of...
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ISBN:
(数字)9781467300476
ISBN:
(纸本)9781467300490
In the last years, a huge effort has been devoted to the improvement of simulation tools for Vehicular Ad-Hoc Networks (VANETs). However, one gap still needs to be filled: tools supporting the precise comprehension of the achieved numerical results, are not available yet; in fact, simulation platforms usually lead to quantitative figures which can be investigated only by statistics. Conversely, the simulation outputs are huge and depend on several aspects - such as mobility and position-dependent phenomena; consequently, they are particularly difficult to be comprehensively understood. While this aspect may seem negligible, it can strongly hamper the usability of the results. It is then envisioned the possibility to boost the analysis of network simulations by means of interactive tools. VisMagna is a visualization tool, specifically meant to support the understanding of complex VANET scenarios. The paper introduces it and shows it at work, highlighting the deeper understanding enabled by it.
This talk reviews several recent NDE datavisualization and analysis improvements implemented at NASA Glenn Research Center. Examples will be shown in the areas of X‐ray computed tomography and waveform‐based NDE. E...
This talk reviews several recent NDE datavisualization and analysis improvements implemented at NASA Glenn Research Center. Examples will be shown in the areas of X‐ray computed tomography and waveform‐based NDE. Emphasis is on methods that are most useful not only for the NDE professional analyzing the data but also for sharing of the data with customers such as material processors, testers, and modelers who need to use the data for various engineering decisions.
visualization technique is a powerful method used by science and technology intelligence analysis experts to identify technical competitor *** visualization methods tend to create graphs meeting the aesthetic criteria...
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visualization technique is a powerful method used by science and technology intelligence analysis experts to identify technical competitor *** visualization methods tend to create graphs meeting the aesthetic criteria instead of finding better clusters,and their analysis results may provide misleading information.A process model of technical group identification method was presented using LinLog graph clustering algorithm to find better competitor *** the model,technical similarity value of each pair of competitors is measured based on their R&D output in sub-fields,and two competitors have a link when they have high similarity value;LinLog algorithm,which is aimed at producing better clusters,was employed to layout graph with competitors as nodes,their links as edges and technology similarity values as weights of *** results show the efficiency of presented method.
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