19,978 research outputs found

    Enabling Adaptive Grid Scheduling and Resource Management

    Get PDF
    Wider adoption of the Grid concept has led to an increasing amount of federated computational, storage and visualisation resources being available to scientists and researchers. Distributed and heterogeneous nature of these resources renders most of the legacy cluster monitoring and management approaches inappropriate, and poses new challenges in workflow scheduling on such systems. Effective resource utilisation monitoring and highly granular yet adaptive measurements are prerequisites for a more efficient Grid scheduler. We present a suite of measurement applications able to monitor per-process resource utilisation, and a customisable tool for emulating observed utilisation models. We also outline our future work on a predictive and probabilistic Grid scheduler. The research is undertaken as part of UK e-Science EPSRC sponsored project SO-GRM (Self-Organising Grid Resource Management) in cooperation with BT

    Towards adaptive multi-robot systems: self-organization and self-adaptation

    Get PDF
    Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.The development of complex systems ensembles that operate in uncertain environments is a major challenge. The reason for this is that system designers are not able to fully specify the system during specification and development and before it is being deployed. Natural swarm systems enjoy similar characteristics, yet, being self-adaptive and being able to self-organize, these systems show beneficial emergent behaviour. Similar concepts can be extremely helpful for artificial systems, especially when it comes to multi-robot scenarios, which require such solution in order to be applicable to highly uncertain real world application. In this article, we present a comprehensive overview over state-of-the-art solutions in emergent systems, self-organization, self-adaptation, and robotics. We discuss these approaches in the light of a framework for multi-robot systems and identify similarities, differences missing links and open gaps that have to be addressed in order to make this framework possible

    A Complexity Science Based Approach to Programme Risk Management

    Get PDF
    Programme management has rapidly gained acceptance as a vehicle for achieving organisational strategic objectives and as a means of aligning projects with the overall strategy of the organisation. Managing programme risk poses challenges which are different from those in project management. Attempts to modify and apply project risk management techniques to programme risk management have experienced difficulties. The implications of the challenges of programme risk management extend beyond the tools and techniques. Recent research shows that that programme management is neither an extension, nor a scaled up version of project management. Philosophically, a paradigm shift from the predominantly mechanistic and reductionist mindset to a more appropriate paradigm based on complexity science and the theory of complex adaptive systems is required. This leads to the conclusion that the classic event based view of risk is inappropriate in modelling and analysing programme risk which need to be treated as holistic and dynamic

    A Complexity Science Based Approach to Programme Risk Management

    Get PDF
    Programme management has rapidly gained acceptance as a vehicle for achieving organisational strategic objectives and as a means of aligning projects with the overall strategy of the organisation. Managing programme risk poses challenges which are different from those in project management. Attempts to modify and apply project risk management techniques to programme risk management have experienced difficulties. The implications of the challenges of programme risk management extend beyond the tools and techniques. Recent research shows that that programme management is neither an extension, nor a scaled up version of project management. Philosophically, a paradigm shift from the predominantly mechanistic and reductionist mindset to a more appropriate paradigm based on complexity science and the theory of complex adaptive systems is required. This leads to the conclusion that the classic event based view of risk is inappropriate in modelling and analysing programme risk which need to be treated as holistic and dynamic

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

    Get PDF
    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
    corecore