2,398 research outputs found
Economic method for measuring ultra-low flow rates of fluids
Capillary tube flowmeter measures ultra-low flows of very corrosive fluids /such as chlorine trifluoride and liquid fluorine/ and other liquids with reasonable accuracy. Flowmeter utilizes differential pressure transducer and operates on the principle that for laminar flow in the tube, pressure drop is proportional to flow rate
Distributed Diffusion-Based LMS for Node-Specific Adaptive Parameter Estimation
A distributed adaptive algorithm is proposed to solve a node-specific
parameter estimation problem where nodes are interested in estimating
parameters of local interest, parameters of common interest to a subset of
nodes and parameters of global interest to the whole network. To address the
different node-specific parameter estimation problems, this novel algorithm
relies on a diffusion-based implementation of different Least Mean Squares
(LMS) algorithms, each associated with the estimation of a specific set of
local, common or global parameters. Coupled with the estimation of the
different sets of parameters, the implementation of each LMS algorithm is only
undertaken by the nodes of the network interested in a specific set of local,
common or global parameters. The study of convergence in the mean sense reveals
that the proposed algorithm is asymptotically unbiased. Moreover, a
spatial-temporal energy conservation relation is provided to evaluate the
steady-state performance at each node in the mean-square sense. Finally, the
theoretical results and the effectiveness of the proposed technique are
validated through computer simulations in the context of cooperative spectrum
sensing in Cognitive Radio networks.Comment: 13 pages, 6 figure
Disruption of a Red Giant Star by a Supermassive Black Hole and the Case of PS1-10jh
The development of a new generation of theoretical models for tidal
disruptions is timely, as increasingly diverse events are being captured in
surveys of the transient sky. Recently, Gezari et al. reported a discovery of a
new class of tidal disruption events: the disruption of a helium-rich stellar
core, thought to be a remnant of a red giant (RG) star. Motivated by this
discovery and in anticipation of others, we consider tidal interaction of an RG
star with a supermassive black hole (SMBH) which leads to the stripping of the
stellar envelope and subsequent inspiral of the compact core toward the black
hole. Once the stellar envelope is removed the inspiral of the core is driven
by tidal heating as well as the emission of gravitational radiation until the
core either falls into the SMBH or is tidally disrupted. In the case of tidal
disruption candidate PS1-10jh we find that there is a set of orbital solutions
at high eccentricities in which the tidally stripped hydrogen envelope is
accreted by the SMBH before the helium core is disrupted. This places the RG
core in a portion of parameter space where strong tidal heating can lift the
degeneracy of the compact remnant and disrupt it before it reaches the tidal
radius. We consider how this sequence of events explains the puzzling absence
of the hydrogen emission lines from the spectrum of PS1-10jh and gives rise to
its other observational features.Comment: Revised version accepted for publication in ApJ, 788, 99 (12 pages, 2
figures
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