12,460 research outputs found
Dynamics in crop protection, agriculture and the food chain in Europe
Overview on the vital role of plant protection in Europe in maintaining and enhancing the dynamics of agricultural production and the food chain. The report offers an overview of the achievements of more sustainable production methods in European agriculture, and the actions taken by the farming community in response to private market initiatives and public policies. Such actions establish new farming systems. The report offers factual information, as well as analyses to put trends in context
General discussion : Weiner-Wright : Interchange fees in various countries : developments and determinants
Debit cards ; Credit cards
A parallel algorithm for global routing
A Parallel Hierarchical algorithm for Global Routing (PHIGURE) is presented. The router is based on the work of Burstein and Pelavin, but has many extensions for general global routing and parallel execution. Main features of the algorithm include structured hierarchical decomposition into separate independent tasks which are suitable for parallel execution and adaptive simplex solution for adding feedthroughs and adjusting channel heights for row-based layout. Alternative decomposition methods and the various levels of parallelism available in the algorithm are examined closely. The algorithm is described and results are presented for a shared-memory multiprocessor implementation
Probability of Reflection by a Random Laser
A theory is presented (and supported by numerical simulations) for
phase-coherent reflection of light by a disordered medium which either absorbs
or amplifies radiation. The distribution of reflection eigenvalues is shown to
be the Laguerre ensemble of random-matrix theory. The statistical fluctuations
of the albedo (the ratio of reflected and incident power) are computed for
arbitrary ratio of sample thickness, mean free path, and absorption or
amplification length. On approaching the laser threshold all moments of the
distribution of the albedo diverge. Its modal value remains finite, however,
and acquires an anomalous dependence on the illuminated surface area.Comment: 8 pages (revtex), 3 figures, to appear in Phys.Rev.Let
Tight bounds for break minimization
We consider round-robin sports tournaments with n teams and n − 1 rounds. We construct an infinite family of opponent schedules for which every home-away assignment induces at least 1/4 n(n−2) breaks. This construction establishes a matching lower bound for a corresponding upper bound from the literature
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