41,727 research outputs found
Opponents and supporters of water policy change in the Netherlands and Hungary
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
Advanced passive communication satellite systems comparison studies. Volume 2 - Technical discussion Final report
Passive communication satellites feasibility for Comsat system - Vol.
Electroweak Radiative Corrections to Off-Shell W-Pair Production
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
Efficiency versus Convergence of Boolean Kernels for On-Line Learning Algorithms
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
Multichannel spectroscopy guide
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
Quantitative flaw characterization with scanning laser acoustic microscopy
Surface roughness and diffraction are two factors that have been observed to affect the accuracy of flaw characterization with scanning laser acoustic microscopy. In accuracies can arise when the surface of the test sample is acoustically rough. It is shown that, in this case, Snell's law is no longer valid for determining the direction of sound propagation within the sample. The relationship between the direction of sound propagation within the sample, the apparent flaw depth, and the sample's surface roughness is investigated. Diffraction effects can mask the acoustic images of minute flaws and make it difficult to establish their size, depth, and other characteristics. It is shown that for Fraunhofer diffraction conditions the acoustic image of a subsurface defect corresponds to a two-dimensional Fourier transform. Transforms based on simulated flaws are used to infer the size and shape of the actual flaw
Distributed intelligent control and management (DICAM) applications and support for semi-automated development
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
Bubble statistics and coarsening dynamics for quasi-two dimensional foams with increasing liquid content
We report on the statistics of bubble size, topology, and shape and on their
role in the coarsening dynamics for foams consisting of bubbles compressed
between two parallel plates. The design of the sample cell permits control of
the liquid content, through a constant pressure condition set by the height of
the foam above a liquid reservoir. We find that in the scaling state, all
bubble distributions are independent not only of time but also of liquid
content. For coarsening, the average rate decreases with liquid content due to
the blocking of gas diffusion by Plateau borders inflated with liquid. By
observing the growth rate of individual bubbles, we find that von Neumann's law
becomes progressively violated with increasing wetness and with decreasing
bubble size. We successfully model this behavior by explicitly incorporating
the border blocking effect into the von Neumann argument. Two dimensionless
bubble shape parameters naturally arise, one of which is primarily responsible
for the violation of von Neumann's law for foams that are not perfectly dry
Probing anomalous quartic gauge-boson couplings via e+e- --> 4fermions+gamma
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
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