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231.
Yaniv Altshuler Michael Fire Erez Shmueli Yuval Elovici Alfred Bruckstein Alex Pentland David Lazer 《Journal of statistical physics》2013,152(3):399-418
This paper develops a methodology to aggregate signals in a network regarding some hidden state of the world. We argue that focusing on edges around hubs will under certain circumstances amplify the faint signals disseminating in a network, allowing for more efficient detection of that hidden state. We apply this method to detecting emergencies in mobile phone data, demonstrating that under a broad range of cases and a constraint in how many edges can be observed at a time, focusing on the egocentric networks around key hubs will be more effective than sampling random edges. We support this conclusion analytically, through simulations, and with analysis of a dataset containing the call log data from a major mobile carrier in a European nation. 相似文献
232.
Yuval Ginosar 《代数通讯》2013,41(1):53-62
The problem of determining when a (classical) crossed product T = S f ?G of a finite group G over a discrete valuation ring S is a maximal order, was answered in the 1960s for the case where S is tamely ramified over the subring of invariants S G . The answer was given in terms of the conductor subgroup (with respect to f) of the inertia. In this article we solve this problem in general when S/S G is residually separable. We show that the maximal order property entails a restrictive structure on the subcrossed product graded by the inertia subgroup. In particular, the inertia is abelian. Using this structure, one is able to extend the notion of the conductor. As in the tame case, the order of the conductor is equal to the number of maximal two-sided ideals of T and hence to the number of maximal orders containing T in its quotient ring. Consequently, T is a maximal order if and only if the conductor subgroup is trivial. 相似文献
233.
Amir Dembo Yuval Peres Jay Rosen Ofer Zeitouni 《Transactions of the American Mathematical Society》2002,354(12):4969-5003
Let denote the number of visits to of the simple planar random walk , up to step . Let be another simple planar random walk independent of . We show that for any , there are points for which . This is the discrete counterpart of our main result, that for any , the Hausdorff dimension of the set of thick intersection points for which , is almost surely . Here is the projected intersection local time measure of the disc of radius centered at for two independent planar Brownian motions run until time . The proofs rely on a ``multi-scale refinement' of the second moment method. In addition, we also consider analogous problems where we replace one of the Brownian motions by a transient stable process, or replace the disc of radius centered at by for general sets .
234.
Yuval Ne'eman 《Foundations of Physics》1985,15(3):261-277
We relate personal encounters of three kinds with geometrical approaches, in the development of a relativistic quantum field theory of the fundamental interactions—including interactions with Nathan Rosen. We characterize the geometrical structures involved and discuss the more recent attempts to develop a unified theory based on a Klein-Kaluza contraction of the eightfold extended supergravity.Invited paper, dedicated to Nathan Rosen on the occasion of his seventy-fifth birthday.On leave from Tel Aviv University, Israel, and the University of Texas at Austin, Texas. 相似文献
235.
Yuval Z. Flicker 《Journal d'Analyse Mathématique》1981,52(1):39-52
An identity of trace formulae which appears in the theory of base change forU(3) is proven for arbitrary matching functions, under no restriction on any component. The method requires no detailed analysis
of weighted orbital integrals, or of orbital integrals of singular classes. 相似文献
236.
237.
238.
The supergroup defines a model with 8 generations of quarks and leptons. One half of these are chiral-inverted. The model represents an anomaly-free gauge unification theory (GUT). 相似文献
239.
240.
We extend the theory of a zero-bias anomaly (ZBA) in the tunneling density of states of a diffusive metallic film to out-of-equilibrium conditions. An effective action describing virtual fluctuations out of equilibrium is derived. The singular behavior of the equilibrium ZBA is smoothed out by real processes of inelastic scattering. 相似文献