40,835 research outputs found

    Designing visual analytics methods for massive collections of movement data

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    Exploration and analysis of large data sets cannot be carried out using purely visual means but require the involvement of database technologies, computerized data processing, and computational analysis methods. An appropriate combination of these technologies and methods with visualization may facilitate synergetic work of computer and human whereby the unique capabilities of each “partner” can be utilized. We suggest a systematic approach to defining what methods and techniques, and what ways of linking them, can appropriately support such a work. The main idea is that software tools prepare and visualize the data so that the human analyst can detect various types of patterns by looking at the visual displays. To facilitate the detection of patterns, we must understand what types of patterns may exist in the data (or, more exactly, in the underlying phenomenon). This study focuses on data describing movements of multiple discrete entities that change their positions in space while preserving their integrity and identity. We define the possible types of patterns in such movement data on the basis of an abstract model of the data as a mathematical function that maps entities and times onto spatial positions. Then, we look for data transformations, computations, and visualization techniques that can facilitate the detection of these types of patterns and are suitable for very large data sets – possibly too large for a computer's memory. Under such constraints, visualization is applied to data that have previously been aggregated and generalized by means of database operations and/or computational techniques

    We Are What We See? – Aggression and Neurological Activation Towards Affective Imagery

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    Violent and erotic media has been suggested to have a long-lasting negative effect on both the brain and behaviour (e.g. Anderson & Bushman, 2001; Grimes, Anderson & Bergen, 2008) and has been linked with increased aggression (Anderson & Bushman, 2001, 2002; Bartholow, Bushman, & Sestir, 2006; Engelhardt, Bartholow, & Saults, 2011; Greitemeyer, 2018). This thesis is the first comprehensive investigation into the effects of aggression and visual media content on early neurological response. Despite adopting gold-standard measures of aggression and contemporary EEG methodology, there was no evidence to support claims of a negative effect using a range of differing content visual stimuli. However, participant sex was identified as a key defining factor in electrocortical response towards all stimuli categories. In general, females tended to respond with an early negativity bias and an increased overall response in comparison to males. This was especially found where the content was related to biological drives. Support was found for research and theory providing that attention is motivated towards evolutionary salient stimuli (e.g. Gur et al, 2002; Kim et al. 2013; Schupp, Junghofer, Weike and Hamm, 2003; Weinberg and Hajak, 2010; Wheaton et al, 2013), and preferred media content (Boheart, 2001; Nordstrom and Wiens, 2012). A variety of measures of aggression have been employed within the field with inconsistencies across procedure, analysis method and reporting that has impacted objectivity and the validity of findings. Four methods of data processing were employed in order to analyze scores on trait aggression scales. Results showed that trait aggression appeared to modulate ERP response towards affective imagery. However, this finding was sex specific (for males only) and was dependent on data processing method employed thus, was inconsistent. This identified that minor modifications to simple data processing techniques have major implications on results and meaning. These findings have clearly demonstrated the need for standardization of methods and analysis across processes, measurement tools and techniques. Additional investigation found that there were numerous elements of stimuli content and context that influenced response. This included neutral stimuli. Taken together, these findings have made a clear case for the requirement of a valid stimuli collection that encompasses a stringent classification of appropriate content that can be widely adopted across research within multiple disciplines

    Exploring time diaries using semi-automated activity pattern extraction

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    Identifying patterns of activities in time diaries in order to understand the variety of daily life in terms of combinations of activities performed by individuals in different groups is of interest in time use research. So far, activity patterns have mostly been identified by visually inspecting representations of activity data or by using sequence comparison methods, such as sequence alignment, in order to cluster similar data and then extract representative patterns from these clusters. Both these methods are sensitive to data size, pure visual methods become too cluttered and sequence comparison methods become too time consuming. Furthermore, the patterns identified by both methods represent mostly general trends of activity in a population, while detail and unexpected features hidden in the data are often never revealed. We have implemented an algorithm that searches the time diaries and automatically extracts all activity patterns meeting user-defined criteria of what constitutes a valid pattern of interest for the user’s research question. Amongst the many criteria which can be applied are a time window containing the pattern, minimum and maximum occurrences of the pattern, and number of people that perform it. The extracted activity patterns can then be interactively filtered, visualized and analyzed to reveal interesting insights. Exploration of the results of each pattern search may result in new hypotheses which can be subsequently explored by altering the search criteria. To demonstrate the value of the presented approach we consider and discuss sequential activity patterns at a population level, from a single day perspective.Time-geography, diaries, everyday life, activity patterns, visualization, data mining, sequential pattern mining

    Sonification of Network Traffic Flow for Monitoring and Situational Awareness

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    Maintaining situational awareness of what is happening within a network is challenging, not least because the behaviour happens within computers and communications networks, but also because data traffic speeds and volumes are beyond human ability to process. Visualisation is widely used to present information about the dynamics of network traffic dynamics. Although it provides operators with an overall view and specific information about particular traffic or attacks on the network, it often fails to represent the events in an understandable way. Visualisations require visual attention and so are not well suited to continuous monitoring scenarios in which network administrators must carry out other tasks. Situational awareness is critical and essential for decision-making in the domain of computer network monitoring where it is vital to be able to identify and recognize network environment behaviours.Here we present SoNSTAR (Sonification of Networks for SiTuational AwaReness), a real-time sonification system to be used in the monitoring of computer networks to support the situational awareness of network administrators. SoNSTAR provides an auditory representation of all the TCP/IP protocol traffic within a network based on the different traffic flows between between network hosts. SoNSTAR raises situational awareness levels for computer network defence by allowing operators to achieve better understanding and performance while imposing less workload compared to visual techniques. SoNSTAR identifies the features of network traffic flows by inspecting the status flags of TCP/IP packet headers and mapping traffic events to recorded sounds to generate a soundscape representing the real-time status of the network traffic environment. Listening to the soundscape allows the administrator to recognise anomalous behaviour quickly and without having to continuously watch a computer screen.Comment: 17 pages, 7 figures plus supplemental material in Github repositor

    What Makes Foreign Knowledge Attractive to Domestic Innovation Managers?

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    This study focuses on the early stages of international innovation activities, i.e. the organizational processes through which promising ideas from around the globe are collected and evaluated. We ask: What characteristics make foreign knowledge interesting to domestic R&D managers? We envision this process as a balancing act between direct transaction costs for communication and coordination and indirect transaction costs from overlooking or misinterpreting important global trends. These hypotheses are tested through a conjoint analysis among 158 heads of R&D departments of German high-tech firms. We find that uncertainty avoidance is the most important driver. Radically new ideas from dynamic markets are most attractive and must not be overlooked. Complementarities with existing knowledge stocks and low language barriers are also important but to a lesser degree. Interestingly, we find no distinction between market and technological impulses. --Globalization,sensing,innovation impulses,conjoint analysis

    AI Solutions for MDS: Artificial Intelligence Techniques for Misuse Detection and Localisation in Telecommunication Environments

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    This report considers the application of Articial Intelligence (AI) techniques to the problem of misuse detection and misuse localisation within telecommunications environments. A broad survey of techniques is provided, that covers inter alia rule based systems, model-based systems, case based reasoning, pattern matching, clustering and feature extraction, articial neural networks, genetic algorithms, arti cial immune systems, agent based systems, data mining and a variety of hybrid approaches. The report then considers the central issue of event correlation, that is at the heart of many misuse detection and localisation systems. The notion of being able to infer misuse by the correlation of individual temporally distributed events within a multiple data stream environment is explored, and a range of techniques, covering model based approaches, `programmed' AI and machine learning paradigms. It is found that, in general, correlation is best achieved via rule based approaches, but that these suffer from a number of drawbacks, such as the difculty of developing and maintaining an appropriate knowledge base, and the lack of ability to generalise from known misuses to new unseen misuses. Two distinct approaches are evident. One attempts to encode knowledge of known misuses, typically within rules, and use this to screen events. This approach cannot generally detect misuses for which it has not been programmed, i.e. it is prone to issuing false negatives. The other attempts to `learn' the features of event patterns that constitute normal behaviour, and, by observing patterns that do not match expected behaviour, detect when a misuse has occurred. This approach is prone to issuing false positives, i.e. inferring misuse from innocent patterns of behaviour that the system was not trained to recognise. Contemporary approaches are seen to favour hybridisation, often combining detection or localisation mechanisms for both abnormal and normal behaviour, the former to capture known cases of misuse, the latter to capture unknown cases. In some systems, these mechanisms even work together to update each other to increase detection rates and lower false positive rates. It is concluded that hybridisation offers the most promising future direction, but that a rule or state based component is likely to remain, being the most natural approach to the correlation of complex events. The challenge, then, is to mitigate the weaknesses of canonical programmed systems such that learning, generalisation and adaptation are more readily facilitated
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