31,736 research outputs found

    A biologically inspired meta-control navigation system for the Psikharpax rat robot

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    A biologically inspired navigation system for the mobile rat-like robot named Psikharpax is presented, allowing for self-localization and autonomous navigation in an initially unknown environment. The ability of parts of the model (e. g. the strategy selection mechanism) to reproduce rat behavioral data in various maze tasks has been validated before in simulations. But the capacity of the model to work on a real robot platform had not been tested. This paper presents our work on the implementation on the Psikharpax robot of two independent navigation strategies (a place-based planning strategy and a cue-guided taxon strategy) and a strategy selection meta-controller. We show how our robot can memorize which was the optimal strategy in each situation, by means of a reinforcement learning algorithm. Moreover, a context detector enables the controller to quickly adapt to changes in the environment-recognized as new contexts-and to restore previously acquired strategy preferences when a previously experienced context is recognized. This produces adaptivity closer to rat behavioral performance and constitutes a computational proposition of the role of the rat prefrontal cortex in strategy shifting. Moreover, such a brain-inspired meta-controller may provide an advancement for learning architectures in robotics

    AUTOMATED META-ACTIONS DISCOVERY FOR PERSONALIZED MEDICAL TREATMENTS

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    Healthcare, among other domains, provides an attractive ground of work for knowl- edge discovery researchers. There exist several branches of health informatics and health data-mining from which we find actionable knowledge discovery is underserved. Actionable knowledge is best represented by patterns of structured actions that in- form decision makers about actions to take rather than providing static information that may or may not hint to actions. The Action rules model is a good example of active structured action patterns that informs us about the actions to perform to reach a desired outcome. It is augmented by the meta-actions model that rep- resents passive structured effects triggered by the application of an action. In this dissertation, we focus primarily on the meta-actions model that can be mapped to medical treatments and their effects in the healthcare arena. Our core contribution lies in structuring meta-actions and their effects (positive, neutral, negative, and side effects) along with mining techniques and evaluation metrics for meta-action effects. In addition to the mining techniques for treatment effects, this dissertation provides analysis and prediction of side effects, personalized action rules, alternatives for treat- ments with negative outcomes, evaluation for treatments success, and personalized recommendations for treatments. We used the tinnitus handicap dataset and the Healthcare Cost and Utilization Project (HCUP) Florida State Inpatient Databases (SID 2010) to validate our work. The results show the efficiency of our methods

    The Use of Marketing Knowledge in Formulating and Enforcing Consumer Protection Policy

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    The purpose of this first chapter of the handbook is to discuss how the findings and approaches offered by the marketing discipline are used in consumer protection policy

    Event-Oriented Dynamic Adaptation of Workflows: Model, Architecture and Implementation

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    Workflow management is widely accepted as a core technology to support long-term business processes in heterogeneous and distributed environments. However, conventional workflow management systems do not provide sufficient flexibility support to cope with the broad range of failure situations that may occur during workflow execution. In particular, most systems do not allow to dynamically adapt a workflow due to a failure situation, e.g., to dynamically drop or insert execution steps. As a contribution to overcome these limitations, this dissertation introduces the agent-based workflow management system AgentWork. AgentWork supports the definition, the execution and, as its main contribution, the event-oriented and semi-automated dynamic adaptation of workflows. Two strategies for automatic workflow adaptation are provided. Predictive adaptation adapts workflow parts affected by a failure in advance (predictively), typically as soon as the failure is detected. This is advantageous in many situations and gives enough time to meet organizational constraints for adapted workflow parts. Reactive adaptation is typically performed when predictive adaptation is not possible. In this case, adaptation is performed when the affected workflow part is to be executed, e.g., before an activity is executed it is checked whether it is subject to a workflow adaptation such as dropping, postponement or replacement. In particular, the following contributions are provided by AgentWork: A Formal Model for Workflow Definition, Execution, and Estimation: In this context, AgentWork first provides an object-oriented workflow definition language. This language allows for the definition of a workflow\u92s control and data flow. Furthermore, a workflow\u92s cooperation with other workflows or workflow systems can be specified. Second, AgentWork provides a precise workflow execution model. This is necessary, as a running workflow usually is a complex collection of concurrent activities and data flow processes, and as failure situations and dynamic adaptations affect running workflows. Furthermore, mechanisms for the estimation of a workflow\u92s future execution behavior are provided. These mechanisms are of particular importance for predictive adaptation. Mechanisms for Determining and Processing Failure Events and Failure Actions: AgentWork provides mechanisms to decide whether an event constitutes a failure situation and what has to be done to cope with this failure. This is formally achieved by evaluating event-condition-action rules where the event-condition part describes under which condition an event has to be viewed as a failure event. The action part represents the necessary actions needed to cope with the failure. To support the temporal dimension of events and actions, this dissertation provides a novel event-condition-action model based on a temporal object-oriented logic. Mechanisms for the Adaptation of Affected Workflows: In case of failure situations it has to be decided how an affected workflow has to be dynamically adapted on the node and edge level. AgentWork provides a novel approach that combines the two principal strategies reactive adaptation and predictive adaptation. Depending on the context of the failure, the appropriate strategy is selected. Furthermore, control flow adaptation operators are provided which translate failure actions into structural control flow adaptations. Data flow operators adapt the data flow after a control flow adaptation, if necessary. Mechanisms for the Handling of Inter-Workflow Implications of Failure Situations: AgentWork provides novel mechanisms to decide whether a failure situation occurring to a workflow affects other workflows that communicate and cooperate with this workflow. In particular, AgentWork derives the temporal implications of a dynamic adaptation by estimating the duration that will be needed to process the changed workflow definition (in comparison with the original definition). Furthermore, qualitative implications of the dynamic change are determined. For this purpose, so-called quality measuring objects are introduced. All mechanisms provided by AgentWork include that users may interact during the failure handling process. In particular, the user has the possibility to reject or modify suggested workflow adaptations. A Prototypical Implementation: Finally, a prototypical Corba-based implementation of AgentWork is described. This implementation supports the integration of AgentWork into the distributed and heterogeneous environments of real-world organizations such as hospitals or insurance business enterprises

    Magpie: towards a semantic web browser

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    Web browsing involves two tasks: finding the right web page and then making sense of its content. So far, research has focused on supporting the task of finding web resources through ‘standard’ information retrieval mechanisms, or semantics-enhanced search. Much less attention has been paid to the second problem. In this paper we describe Magpie, a tool which supports the interpretation of web pages. Magpie offers complementary knowledge sources, which a reader can call upon to quickly gain access to any background knowledge relevant to a web resource. Magpie automatically associates an ontologybased semantic layer to web resources, allowing relevant services to be invoked within a standard web browser. Hence, Magpie may be seen as a step towards a semantic web browser. The functionality of Magpie is illustrated using examples of how it has been integrated with our lab’s web resources

    The consolidation process of the EU regulatory framework on nanotechnologies: within and beyond the EU case-by-case approach

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    The field of nanotechnologies has been the subject of a process of wide-ranging regulation, which covers two different trends. From the 2000s the European Commission and Parliament agreed on a type of adaptive, experimental and flexible approach, which had its apex with the Commission code of conduct on responsible nano-research developed through a set of consultations. In 2009 this initial agreement subsequently broke down and the EU started to develop a set of regulatory initiatives of a sectoral nature in several fields (cosmetics, food, biocides). Thus, the current arrangement of governance in the field of nanotechnologies appears to be a hybrid, which mixes forms belonging to the new governance method (consultations, self-regulation, agency, comitology committees, networking), working like a lung in the framework of EU policy, with more traditional tools belonging to the classic governance method (regulations, directives). This model of governance based on a case-by-case approach runs the risk of lacking coherence since it is exposed to sudden changes of direction when risks emerge and it has a weak anticipatory dimension due to both its excessive dependency on data collection and its insufficient use of upstream criteria, such as human rights, which should be used earlier, to allow anticipated intervention with a less intense use of hard law solutions

    XANUI: A Textual Platform-Independent Model for Rich User Interfaces

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    In recent years, several model-driven proposals have defined user interface models that can represent both behavioural and aesthetic aspects. However, the software industry has ignored the majority of these proposals because the quality of the rich user interfaces generated out of these models is usually low and their code generators are not flexible, i.e., the UI templates cannot be customised easily. Furthermore, these proposals do not facilitate the separation between the visual design of the UI, normally performed by graphic designers in the industry, and the visualisation of data, which has been previously modelled using another domain-specific language. This paper proposes a new textual domain-specific language called XANUI, which could be embedded in XML-based UI pages, e.g., HTML or XML. The designed language provides the mechanisms to bind visual components with data structures already existing, and to define the behaviour of these components based on events. In this paper, XANUI is integrated in two OOH4RIA development processes, i.e., the traditional data-intensive and the new design-first process, thus reusing the OOH4RIA models and transformations to generate a complete rich Internet application for any platform or device. In order to validate this approach, the XANUI solution is applied to the development of a RIA with two UI types: a) the administration view of a Web application using HTML5 and AngularJS, and b) a catalogue application for e-Commerce using Windows RT in a Tablet PC
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