39,689 research outputs found

    Opponents and supporters of water policy change in the Netherlands and Hungary

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    This paper looks at the role of individuals and the strategies that they use to bring about or oppose major policy change. Current analysis of the role that individuals or small collectives play in periods of major policy change has focussed on strategies that reinforce change and on the supporters of change. This paper adds the perspective of opponents, and asks whether they use similar strategies as those identified for supporters. Five strategies are explored: developing new ideas, building coalitions to sell ideas, using windows of opportunity, playing multiple venues and orchestrating networks. Using empirical evidence from Dutch and Hungarian water policy change, we discuss whether individuals pursued these strategies to support or oppose major policy change. Our analysis showed the significance of recognition of a new policy concept at an abstract level by responsible government actors, as well as their engagement with a credible regional coalition that can contextualise and advocate the concept regionally. The strategies of supporters were also used by opponents of water policy change. Opposition was inherent to policy change, and whether or not government actors sought to engage with opponents influenced the realisation of water policy change

    Efficiency versus Convergence of Boolean Kernels for On-Line Learning Algorithms

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    The paper studies machine learning problems where each example is described using a set of Boolean features and where hypotheses are represented by linear threshold elements. One method of increasing the expressiveness of learned hypotheses in this context is to expand the feature set to include conjunctions of basic features. This can be done explicitly or where possible by using a kernel function. Focusing on the well known Perceptron and Winnow algorithms, the paper demonstrates a tradeoff between the computational efficiency with which the algorithm can be run over the expanded feature space and the generalization ability of the corresponding learning algorithm. We first describe several kernel functions which capture either limited forms of conjunctions or all conjunctions. We show that these kernels can be used to efficiently run the Perceptron algorithm over a feature space of exponentially many conjunctions; however we also show that using such kernels, the Perceptron algorithm can provably make an exponential number of mistakes even when learning simple functions. We then consider the question of whether kernel functions can analogously be used to run the multiplicative-update Winnow algorithm over an expanded feature space of exponentially many conjunctions. Known upper bounds imply that the Winnow algorithm can learn Disjunctive Normal Form (DNF) formulae with a polynomial mistake bound in this setting. However, we prove that it is computationally hard to simulate Winnows behavior for learning DNF over such a feature set. This implies that the kernel functions which correspond to running Winnow for this problem are not efficiently computable, and that there is no general construction that can run Winnow with kernels

    Electroweak Radiative Corrections to Off-Shell W-Pair Production

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    We briefly describe the RacoonWW approach to calculate radiative corrections to e+ e- -> W W -> 4 fermions and present numerical results for the total W-pair production cross section at LEP2.Comment: 3 pages, 2 figures, talk given at the DPF2000 meeting, Columbus, OH, August 9-12, 200

    Distributed intelligent control and management (DICAM) applications and support for semi-automated development

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    We have recently begun a 4-year effort to develop a new technology foundation and associated methodology for the rapid development of high-performance intelligent controllers. Our objective in this work is to enable system developers to create effective real-time systems for control of multiple, coordinated entities in much less time than is currently required. Our technical strategy for achieving this objective is like that in other domain-specific software efforts: analyze the domain and task underlying effective performance, construct parametric or model-based generic components and overall solutions to the task, and provide excellent means for specifying, selecting, tailoring or automatically generating the solution elements particularly appropriate for the problem at hand. In this paper, we first present our specific domain focus, briefly describe the methodology and environment we are developing to provide a more regular approach to software development, and then later describe the issues this raises for the research community and this specific workshop

    Multichannel spectroscopy guide

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    System makes use of diverging duct walls for conducting the light from entrance slips to the conductors by means of multiple reflectors. This system simultaneously records, photoelectrically, the intensities of several closely spaceed narrow wavelengths in the ultraviolet and infrared areas of the spectrum

    Probing anomalous quartic gauge-boson couplings via e+e- --> 4fermions+gamma

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    All lowest-order amplitudes for e+e- --> 4f+gamma are calculated including five anomalous quartic gauge-boson couplings that are allowed by electromagnetic gauge invariance and the custodial SU(2)_c symmetry. Three of these anomalous couplings correspond to the operators L_0, L_c, and L_n that have been constrained by the LEP collaborations in WWgamma production. The anomalous couplings are incorporated in the Monte Carlo generator RACOONWW. Moreover, for the processes e+e- --> 4f+gamma RACOONWW is improved upon including leading universal electroweak corrections such as initial-state radiation. The discussion of numerical results illustrates the size of the leading corrections as well as the impact of the anomalous quartic couplings for LEP2 energies and at 500GeV.Comment: 27 pages, latex, 42 postscript files, some misprints correcte

    W-pair production at future e+e- colliders: precise predictions from RACOONWW

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    We present numerical results for total cross sections and various distributions for e+e- --> WW --> 4f(+gamma) at a future 500GeV linear collider, obtained from the Monte Carlo generator RACOONWW. This generator is the first one that includes O(alpha) electroweak radiative corrections in the double-pole approximation completely. Owing to their large size the corrections are of great phenomenological importance.Comment: 11 pages, latex, 10 postscript file
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