293 research outputs found

    MobilityGraphs: Visual Analysis of Mass Mobility Dynamics via Spatio-Temporal Graphs and Clustering

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    Learning more about people mobility is an important task for official decision makers and urban planners. Mobility data sets characterize the variation of the presence of people in different places over time as well as movements (or flows) of people between the places. The analysis of mobility data is challenging due to the need to analyze and compare spatial situations (i.e., presence and flows of people at certain time moments) and to gain an understanding of the spatio-temporal changes (variations of situations over time). Traditional flow visualizations usually fail due to massive clutter. Modern approaches offer limited support for investigating the complex variation of the movements over longer time periods

    A framework for malicious host fingerprinting using distributed network sensors

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    Numerous software agents exist and are responsible for increasing volumes of malicious traffic that is observed on the Internet today. From a technical perspective the existing techniques for monitoring malicious agents and traffic were not developed to allow for the interrogation of the source of malicious traffic. This interrogation or reconnaissance would be considered active analysis as opposed to existing, mostly passive analysis. Unlike passive analysis, the active techniques are time-sensitive and their results become increasingly inaccurate as time delta between observation and interrogation increases. In addition to this, some studies had shown that the geographic separation of hosts on the Internet have resulted in pockets of different malicious agents and traffic targeting victims. As such it would be important to perform any kind of data collection over various source and in distributed IP address space. The data gathering and exposure capabilities of sensors such as honeypots and network telescopes were extended through the development of near-realtime Distributed Sensor Network modules that allowed for the near-realtime analysis of malicious traffic from distributed, heterogeneous monitoring sensors. In order to utilise the data exposed by the near-realtime Distributed Sensor Network modules an Automated Reconnaissance Framework was created, this framework was tasked with active and passive information collection and analysis of data in near-realtime and was designed from an adapted Multi Sensor Data Fusion model. The hypothesis was made that if sufficiently different characteristics of a host could be identified; combined they could act as a unique fingerprint for that host, potentially allowing for the re-identification of that host, even if its IP address had changed. To this end the concept of Latency Based Multilateration was introduced, acting as an additional metric for remote host fingerprinting. The vast amount of information gathered by the AR-Framework required the development of visualisation tools which could illustrate this data in near-realtime and also provided various degrees of interaction to accommodate human interpretation of such data. Ultimately the data collected through the application of the near-realtime Distributed Sensor Network and AR-Framework provided a unique perspective of a malicious host demographic. Allowing for new correlations to be drawn between attributes such as common open ports and operating systems, location, and inferred intent of these malicious hosts. The result of which expands our current understanding of malicious hosts on the Internet and enables further research in the area

    State of the art 2015: a literature review of social media intelligence capabilities for counter-terrorism

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    Overview This paper is a review of how information and insight can be drawn from open social media sources. It focuses on the specific research techniques that have emerged, the capabilities they provide, the possible insights they offer, and the ethical and legal questions they raise. These techniques are considered relevant and valuable in so far as they can help to maintain public safety by preventing terrorism, preparing for it, protecting the public from it and pursuing its perpetrators. The report also considers how far this can be achieved against the backdrop of radically changing technology and public attitudes towards surveillance. This is an updated version of a 2013 report paper on the same subject, State of the Art. Since 2013, there have been significant changes in social media, how it is used by terrorist groups, and the methods being developed to make sense of it.  The paper is structured as follows: Part 1 is an overview of social media use, focused on how it is used by groups of interest to those involved in counter-terrorism. This includes new sections on trends of social media platforms; and a new section on Islamic State (IS). Part 2 provides an introduction to the key approaches of social media intelligence (henceforth ‘SOCMINT’) for counter-terrorism. Part 3 sets out a series of SOCMINT techniques. For each technique a series of capabilities and insights are considered, the validity and reliability of the method is considered, and how they might be applied to counter-terrorism work explored. Part 4 outlines a number of important legal, ethical and practical considerations when undertaking SOCMINT work

    A Mobility Model for Synthetic Travel Demand from Sparse Traces

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    Knowing how much people travel is essential for transport planning. Empirical mobility traces collected from call detail records (CDRs), location-based social networks (LBSNs), and social media data have been used widely to study mobility patterns. However, these data suffer from sparsity, an issue that has largely been overlooked. In order to extend the use of these low-cost and accessible data, this study proposes a mobility model that fills the gaps in sparse mobility traces from which one can later synthesise travel demand. The proposed model extends the fundamental mechanisms of exploration and preferential return to synthesise mobility trips. The model is tested on sparse mobility traces from Twitter. We validate our model and find good agreement on origin-destination matrices and trip distance distributions for Sweden, the Netherlands, and Sa\uf5 Paulo, Brazil, compared with a benchmark model using a heuristic method, especially for the most frequent trip distance range (1-40 km). Moreover, the learned model parameters are found to be transferable from one region to another. Using the proposed model, reasonable travel demand values can be synthesised from a dataset covering a large enough population of very sparse individual geolocations (around 1.5 geolocations per day covering 100 days on average)
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