A stochastic behavior analysis of stochastic restricted-gradient descent algorithm in reproducing kernel Hilbert spaces

This paper presents a stochastic behavior analysis of a kernel-based stochastic restricted-gradient descent method. The restricted gradient gives a steepest ascent direction within the so-called dictionary subspace. The analysis provides the transient and steady state performance in the mean squared error criterion. It also includes stability conditions in the mean and mean-square sense. The present study is based on the analysis of the kernel normalized least mean square (KNLMS) algorithm initially proposed by Chen et al. Simulation results validate the analysis

Field equations and cosmology for a class of nonlocal metric models of MOND

We consider a class of nonlocal, pure-metric modified gravity models which were developed to reproduce the Tully-Fisher relation without dark matter and without changing the amount of weak lensing predicted by general relativity. Previous work gave only the weak field limiting form of the field equations specialized to a static and spherically symmetric geometry. Here we derive the full field equations and specialize them to a homogeneous, isotropic and spatially flat geometry. We also discuss the problem of fitting the free function to reproduce the expansion history. Results are derived for models in which the MOND acceleration a_0 ~ 1.2 x 10^{-10} m/s^{2} is a fundamental constant and for the more phenomenologically interesting case in which the MOND acceleration changes with the cosmological expansion rate.Comment: 15 pages, no figures, uses revtex4, dedicated to Stanley Deser on the occasion of his 83rd birthda

On the robustness of distributed algorithms

In recent years, numerous distributed algorithms have been proposed which, when executed by a team of dynamic agents, result in the completion of a joint task. However, for any such algorithm to be practical, one should be able to guarantee that the task is still satisfactorily executed even when agents fail to communicate with others or to perform their designated actions correctly. In this paper, we present a concept of robustness which is well-suited for general distributed algorithms for teams of dynamic agents. Our definition extends a similar notion introduced in the distributed computation literature for consensus problems. We illustrate the definition by considering a variety of algorithms

(E)-N-(Ferrocenyl­methyl­idene)(pyridin-3-yl)methanamine

In the title compound, [Fe(C5H5)(C12H11N2)], the cyclo­penta­dienyl rings are present in an eclipsed conformation. The imine is E-configured. In the crystal, C—H⋯N inter­actions involving both N atoms connect the mol­ecules into two undulating sheets perpendicular to the b axis. The centroid–centroid distance between the two aromatic systems in the ferrocenyl moiety is 3.2928 (18) Å. A C–H⋯π inter­action is also present