586,873 research outputs found

    Algorithms and Conditional Lower Bounds for Planning Problems

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    We consider planning problems for graphs, Markov decision processes (MDPs), and games on graphs. While graphs represent the most basic planning model, MDPs represent interaction with nature and games on graphs represent interaction with an adversarial environment. We consider two planning problems where there are k different target sets, and the problems are as follows: (a) the coverage problem asks whether there is a plan for each individual target set, and (b) the sequential target reachability problem asks whether the targets can be reached in sequence. For the coverage problem, we present a linear-time algorithm for graphs and quadratic conditional lower bound for MDPs and games on graphs. For the sequential target problem, we present a linear-time algorithm for graphs, a sub-quadratic algorithm for MDPs, and a quadratic conditional lower bound for games on graphs. Our results with conditional lower bounds establish (i) model-separation results showing that for the coverage problem MDPs and games on graphs are harder than graphs and for the sequential reachability problem games on graphs are harder than MDPs and graphs; (ii) objective-separation results showing that for MDPs the coverage problem is harder than the sequential target problem.Comment: Accepted at ICAPS'1

    Long-term legacy implications for Olympic Games

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    Celebrations have been occurring throughout history from the commemoration of phases of the moon, to historical and cultural festivals in addition to life cycle celebrations of birth, marriage and death. Events came about through the commercialisation of popular celebrations and in the UK as our population becomes more culturally diverse, so do the events appearing showing diversifying into the leisure and every aspect of people’s everyday lives. All these events have impacts and legacies and the larger the size of event the greater these ‘consequences’, with the Olympics having the greatest impacts and legacies. These large scale events also have major benefits including destination image and urban developments, the legacy left behind after the event is held. In order for these benefits to maximise the long-term potential, legacy planning as early as possible is paramount. Case studies of the Sydney Games show that whilst they have been known as ‘the best games ever’ their legacy planning post the games, beginning in 2000, were negligible and the consequences of this are on-going. For the organisers of the Barcelona 1992 Games, their built environment and the re-modelling of the city, was part of a larger scale long-term redevelopment and their legacy planning was part of an overall vision for the city. What appears to be a long-term strategic plan for London, especially in relation to the social impacts of the four main boroughs involved in the staging of the 2012 Games, could become known as the ‘London’ model of urban rejuvenation for future mega-event planners, particularly in relation to the long-term future legacy. This chapter sets put to evaluate the lessons learned from the past Games of Sydney and Barcelona in relation to legacy planning, especially the social consequences, and the ‘best-practice’ lessons to be incorporated within the London 2012 planning in relation to future long-term legacies. London won the right to host the 2012 games on the basis of their regeneration plans for an area of London in socially deprived conditions. All the ‘paper’ promises within the bid document talk of the major regeneration project with the associated large scale spend on infrastructure, it is vital that the promises are turned into long-term viable legacy

    Resilient planning for sporting mega-events: designing and managing safe and secure urban places for London 2012 and beyond

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    Since the 1960s both regeneration and security have been prominent themes in Olympic planning. However, this paper argues that the prominence given to post event 'legacies' in London's bid to host the 2012 Summer Games has fomented a merger of these hitherto distinct ambitions oriented around notions of 'resilience'. In addition to identifying this merger, based on analysis of planning for the 2012 Games the paper sets out its component features and considers a range of key implications. These include the accommodation of Olympic security amid shifting national security arrangements and, at a local level, the impact and importance of the 2011 London riots on Olympic safety and security processes. Organised over four areas of discussion - the first three comprising of the coupling of spatial strategies of resilient planning and design with concerns for security; the temporal framework of such approaches; analysis of the altered physical and institutional landscape of London ahead of the 2012 Olympic Games - the paper concludes by identifying and discussing the ways in which urban rejuvenation and securitisation which are increasingly being combined into resilient designs and master plans in the Olympic context and, crucially, standardised, exported and transferred to new urban hosts of similar events

    Olympic legacy and cultural tourism: Exploring the facets of Athens' Olympic heritage

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    This study examines the effects of the Olympic Games on Athens’ cultural tourism and the city’s potential to leverage the Olympic legacy in synergy with its rich heritage in order to enhance its tourism product during the post-Games period. In doing so, a qualitative and interpretive approach was employed. This includes a literature review on Athens’ 2004 Olympics to identify the sport facilities and regeneration projects, which constitute the Olympic legacy and heritage. Based on that, an empirical analysis was undertaken, by collecting official documents about the 2004 Olympics, and conducting five semi-structured interviews with tourism/administrative officials. The findings indicate that the Olympiad contributed significantly to Athens’ built and human heritage, revealing the dimensions of new venues/facilities, infrastructure, transportation and aesthetic image of the city, and human capital enhancement. Hence, the Games affected to the multifaceted representation and reconstruction of the city’s identity and cultural heritage. However, the potential afforded from the post-Olympic Athens remains unrealised due to lack of strategic planning/management. The study concludes that there is a need to develop cross-leveraging synergies between the Olympic legacy and cultural tourism for the host city. Finally, a strategic planning framework for leveraging post-Games Olympic tourism is suggested in order to maximise the benefits of Olympic legacy and heritage in a host city’s tourism development

    Complete contingency planners

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    A framework is proposed for the investigation of planning systems that must deal with bounded uncertainty. A definition of this new class of contingency planners is given. A general, complete contingency planning algorithm is described. The algorithm is suitable to many incomplete information games as well as planning situations where the initial state is only partially known. A rich domain is identified for the application and evaluation of contingency planners. Preliminary results from applying our complete contingency planner to a portion of this domain are encouraging and match expert level performance
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