5 research outputs found
Faster Rates for Compressed Federated Learning with Client-Variance Reduction
No full textDue to the communication bottleneck in distributed and federated learning
applications, algorithms using communication compression have attracted
significant attention and are widely used in practice. Moreover, the huge
number, high heterogeneity and limited availability of clients result in high
client-variance. This paper addresses these two issues together by proposing
compressed and client-variance reduced methods COFIG and FRECON. We prove an
bound on the number of communication rounds of COFIG in the nonconvex setting,
where is the total number of clients, is the number of clients
participating in each round, is the convergence error, and
is the variance parameter associated with the compression operator. In case of
FRECON, we prove an bound on the
number of communication rounds. In the convex setting, COFIG converges within
communication rounds, which, to the
best of our knowledge, is also the first convergence result for compression
schemes that do not communicate with all the clients in each round. We stress
that neither COFIG nor FRECON needs to communicate with all the clients, and
they enjoy the first or faster convergence results for convex and nonconvex
federated learning in the regimes considered. Experimental results point to an
empirical superiority of COFIG and FRECON over existing baselines.Comment: Accepted by SIAM Journal on Mathematics of Data Science (SIMODS
Teaching Virtual Characters to use Body Language
No full textNon-verbal communication, or “body language”, is a critical component in constructing believable virtual characters. Most often, body language is implemented by a set of ad-hoc rules.We propose a new method for authors to specify and refine their character’s body-language responses. Using our method, the author watches the character acting in a situation, and provides simple feedback on-line. The character then learns to use its body language to maximize the rewards, based on a reinforcement learning algorithm
DOUBLE RESONANCE EXCITATION OF THE RUBIDIUM DIMER : THE 2 STATE
No full textAuthor Institution: Department of Chemistry, Moscow State University, 119991; Moscow, Russia\; Institut Lumiere Matiere, Universite Lyon 1 \& CNRS UMR5306, Universite de Lyon, FranceWe have performed a series of optical-optical double resonance experiments with one or two cw Ti:sapphire lasers, to excite the 2~ state of Rb, recording infrared fluorescence from 2~ on a Fourier transform spectrometer. Fluorescence from the lower vibrational levels of 2~ (T = 22069.56 cm) is dominated by transitions to the B state studied by Amiot and Verges, Chem. Phys. Lett. 294, 91-98 (1997). Vibrational and rotational relaxation from laser-pumped levels v' 35, occurs also to the 0 components of the A~b complex. Fitting all available 2~B~ data for Rb and RbRb (several thousand transitions) has also given an improved description of the bottom of the B state potential well. The 2~ state correlates at long-range with Rb 5s + Rb 4d atoms (A.-R. Allouche, M. Aubert-Frecon, J. Chem Phys 136, 37-41 (2012)), giving a dissociation energy of 1279.6 cm. Most new data lie below v = 45, 250 cm below this dissociation threshold
THE STATE IN - INVESTIGATING A POSSIBLE GATEWAY TO CORE NON-PENETRATING RYDBERG STATES
No full textAuthor Institution: Department of Physics, United States Military Academy; Department of Physics, Temple University; Department of Chemistry, University of Illinois at Chicago; Key Lab Atom and Molecular Nanoscience, Tsinghua University; Laboratoire de Physique des Atomes, Lasers, Mol\'{e}cules et Surfaces, (PALMES), CNRS et Universit\'{e}; Laboratoire de Spectrom\'etrie Ionique et Moleculaire (L.A.S.I.M), CNRS et Universit\'e Lyon (UMR5579)Core non-penetrating Rydberg states can give useful information on the electronic structure of the ion core; however, core non-penetrating states are difficult to observe since these states hardly penetrate the more accessible ion core and the electronic angular momentum quantum number, l, is large, for the core non-penetrating states thus the transition dipole moment to the core non-penetrating states is small. The core penetrating state (atomic limit: ) and the core non-penetrating state (atomic limit: ) perturb each other since they have the same symmetry and overlapping energy states thus creating the possibility of a gateway to other core non-penetrating states
