355 research outputs found
Quantitative games with interval objectives
Traditionally quantitative games such as mean-payoff games and discount sum
games have two players -- one trying to maximize the payoff, the other trying
to minimize it. The associated decision problem, "Can Eve (the maximizer)
achieve, for example, a positive payoff?" can be thought of as one player
trying to attain a payoff in the interval . In this paper we
consider the more general problem of determining if a player can attain a
payoff in a finite union of arbitrary intervals for various payoff functions
(liminf, mean-payoff, discount sum, total sum). In particular this includes the
interesting exact-value problem, "Can Eve achieve a payoff of exactly (e.g.)
0?"Comment: Full version of CONCUR submissio
Looking at Mean-Payoff through Foggy Windows
Mean-payoff games (MPGs) are infinite duration two-player zero-sum games
played on weighted graphs. Under the hypothesis of perfect information, they
admit memoryless optimal strategies for both players and can be solved in
NP-intersect-coNP. MPGs are suitable quantitative models for open reactive
systems. However, in this context the assumption of perfect information is not
always realistic. For the partial-observation case, the problem that asks if
the first player has an observation-based winning strategy that enforces a
given threshold on the mean-payoff, is undecidable. In this paper, we study the
window mean-payoff objectives that were introduced recently as an alternative
to the classical mean-payoff objectives. We show that, in sharp contrast to the
classical mean-payoff objectives, some of the window mean-payoff objectives are
decidable in games with partial-observation
We the people of earth: toward global democracy
We Confront Daunting Twenty-First Century Challenges hobbled by twentieth century institutions. In a world ever more interdependent, deepening global-scale risks – climate change, financial instability, terrorism, to name a few – threaten the planetary commonweal, even the continuity of civilization. Yet coherent and timely responses lie beyond the grasp of our myopic and disputatious state-centric political order. Closing this perilous gap between obsolete geo-politics and emerging
geo-realities delineates an urgent political endeavor: constructing a legitimate and effective system of world governance. Key steps on that path involve reforming the United Nations and nurturing new venues for the meaningful exercise of global citizenshipPreprin
USE OF MIND/BODY SELFHEALING PRACTICE PREDICTS POSITIVE HEALTH TRANSITION IN CHRONIC FATIGUE SYNDROME: A Controlled Study
Seventy subjects diagnosed with chronic fatigue syndrome were randomized to a control group (N=33) or a treatment group (N :; 37). All continued usual medical care. Treatment subjects were assigned to a 9 week, 2-hours-per-week group program teaching mindfulness meditation and medical qigong practices. The outcome variable was 12-month health transition at oneyear follow-up, as defined by the SF36 12-month Health Transition score. The data yielded a classification tree with a 90% overall accuracy rate in classifYing subjects as "improvers" or non-improvers" (effect strength 80.5, experimentwise p < .05), based on SF36 Role FunctioningPhysical score at follow-up and frequency of mind/body self-healing practice. Subjects in the highest quartile of Role Functioning-Physical improved regardless of practice. For the remaining 75%, those practicing three or more days per week at follow-up were 2.7 times more likely to report positive 12-month Health Transition than those practicing less
Transforming innovation for sustainability
The urgency of charting pathways to sustainability that keep human societies within a "safe operating space" has now been clarified. Crises in climate, food, biodiversity, and energy are already playing out across local and global scales and are set to increase as we approach critical thresholds. Drawing together recent work from the Stockholm Resilience Centre, the Tellus Institute, and the STEPS Centre, this commentary article argues that ambitious Sustainable Development Goals are now required along with major transformation, not only in policies and technologies, but in modes of innovation themselves, to meet them. As examples of dryland agriculture in East Africa and rural energy in Latin America illustrate, such "transformative innovation" needs to give far greater recognition and power to grassroots innovation actors and processes, involving them within an inclusive, multi-scale innovation politics. The three dimensions of direction, diversity, and distribution along with new forms of "sustainability brokering" can help guide the kinds of analysis and decision making now needed to safeguard our planet for current and future generations
A Differential Deficit in Time- Versus Event-Based Prospective Memory in Parkinson\u27s Disease
Objective: The aim of the current study was to clarify the nature and extent of impairment in time- versusevent-based prospective memory in Parkinson’s disease (PD). Prospective memory is thought to involvecognitive processes that are mediated by prefrontal systems and are executive in nature. Given thatindividuals with PD frequently show executive dysfunction, it is important to determine whether theseindividuals may have deficits in prospective memory that could impact daily functions, such as takingmedications. Although it has been reported that individuals with PD evidence impairment in prospectivememory, it is still unclear whether they show a greater deficit for time- versus event-based cues. Method:Fifty-four individuals with PD and 34 demographically similar healthy adults were administered astandardized measure of prospective memory that allows for a direct comparison of time-based andevent-based cues. In addition, participants were administered a series of standardized measures ofretrospective memory and executive functions. Results: Individuals with PD demonstrated impairedprospective memory performance compared to the healthy adults, with a greater impairment demonstratedfor the time-based tasks. Time-based prospective memory performance was moderately correlatedwith measures of executive functioning, but only the Stroop Neuropsychological Screening Test emergedas a unique predictor in a linear regression. Conclusions: Findings are interpreted within the context ofMcDaniel and Einstein’s (2000) multiprocess theory to suggest that individuals with PD experienceparticular difficulty executing a future intention when the cue to execute the prescribed intention requireshigher levels of executive control
Measurement of the creep behavior of thin ZrNi metallic glass films – a comparison between nanoindentation relaxation, nanoindentation creep and lab-on-chips experiments
The characterization of the time-dependent behavior of thin metallic glass films is one of the key-issue for surface engineering. Such a measurement requires loading a constant material volume located in the thin film. Unfortunately, this condition is not fulfilled in the commonly used creep nanoindentation testing, contrary to micro tensile lab-on-chip experiments or micropillar compression testing. In this paper, we show that nanoindentation relaxation is an efficient alternative to nanoindentation creep. For that purpose, an extensive study of ZrNi metallic glasses viscoplastic behavior is performed using several experimental set-up (lab on chips, nanoindentation relaxation, nanoindentation creep, constant strain rate, ...). An innovative nanoindentation methodology is used to perform long-term relaxation tests up to 10 h with excellent reproducibility. It consists in maintaining a constant contact area during the test by controlling the contact stiffness between the tip and the material. Nanoindentation relaxation, constant strain rate loading and lab-on-chips data lead to similar values of apparent activation volume and strain rate sensitivity, whereas nanoindentation creep clearly overestimates the activation volume (Fig 1). Finite element modelling of nanoindentation creep and nanoindentation relaxation also confirms this trend. We evidence, thanks to the long-term indentation relaxation test that the underlying deformation mechanisms remain unchanged on the entire investigated strain rate range.
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Making the great transformation, November 13, 14, and 15, 2003
This repository item contains a single issue of the Pardee Conference Series, a publication series that began publishing in 2006 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future. This Conference took place during November 13, 14, and 15, 2003. Co-organized by Cutler Cleveland and Adil Najam.The conference discussants and participants analyze why transitions happen, and why they matter. Transitions are those wide-ranging changes in human organization and well being that can be convincingly attributed to a concerted set of choices that make the world that was significantly and recognizably different from the world that becomes.
Transition scholars argue that that history does not just stumble along a pre-determined path, but that human ingenuity and entrepreneurship have the ability to fundamentally alter its direction. However, our ability to ‘will’ such transitions remains in doubt. These doubts cannot be removed until we have a better understanding of how transitions work
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