11,299 research outputs found
Leak detector
A detector for sensing a leaking of fluid pressures is reported. The detector is characterized by an hermetically sealed housing confining therewithin a first normalized pressure, a connector for coupling the housing in direct communication with a suspected leak established within a substantially sealed body, an electrical circuit having a first or normalized configuration and including a pair of circuit completing electrical contacts and means mounting at least one contact of said pair of contacts on a flexible wall of the housing supporting the contact for movement from a first position along a linear path to a second position in response to an altering of the pressure confined within the housing for thereby altering the configuration of the circuit
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HIPAA vs. CIPA (California Invasion of Privacy Act): Are Physicians Protected from Live Social Media Streaming in the Emergency Department?
Two Weight Inequalities for Discrete Positive Operators
We characterize two weight inequalities for general positive dyadic
operators. We consider both weak and strong type inequalities, and general
(p,q) mapping properties. Special cases include Sawyers Fractional Integral
operator results from 1988, and the bilinear embedding inequality of
Nazarov-Treil-Volberg from 1999. The method of proof is an extension of
Sawyer's argument.Comment: 20 pages, 3 figures. v2 correction of minor typos v3: Correction of
typos. v4: Two references adde
A Two Weight Inequality for the Hilbert transform Assuming an Energy Hypothesis
Subject to a range of side conditions, the two weight inequality for the
Hilbert transform is characterized in terms of (1) a Poisson A_2 condition on
the weights (2) A forward testing condition, in which the two weight inequality
is tested on intervals (3) and a backwards testing condition, dual to (2). A
critical new concept in the proof is an Energy Condition, which incorporates
information about the distribution of the weights in question inside intervals.
This condition is a consequence of the three conditions above. The Side
Conditions are termed 'Energy Hypotheses'. At one endpoint they are necessary
for the two weight inequality, and at the other, they are the Pivotal
Conditions of Nazarov-Treil-Volberg. This new concept is combined with a known
proof strategy devised by Nazarov-Treil-Volberg. A counterexample shows that
the Pivotal Condition are not necessary for the two weight inequality.Comment: 60 pages, 1 figure. v3. An important revision: The Energy Condition
is reformulated, a key concept of the proof, is reformulated. The main result
is unchanged. v4. important display corrected. v6: The earlier versions
incorrectly claimed a characterization, as was pointed out to us by S. Treil
v7. Corrections in Section
Mean lattice point discrepancy bounds, II: Convex domains in the plane
We consider planar curved strictly convex domains with no or very weak
smoothness assumptions and prove sharp bounds for square-functions associated
to the lattice point discrepancy.Comment: Revised version, to appear in Journal d'Analyse Mathematiqu
Turbulence, combustion, pollutant, and stability characterization of a premixed, step combustor
A two dimensional combustion tunnel was constructed to study a lean premixed turbulent propane/air flame stablized behind a rearward facing step. Studied were: (1) the existence and importance of large coherent structures in turbulent reacting and nonreacting free shear layers behind the steps; (2) the effect of inlet temperature and reference velocity on combustion efficiency; (3) CO, NO2 and NO sub x production in the flame; and (4) the blowout and upstream propagation of the flame. In the ranges studied, the large coherent structures dominated both the reacting and the nonreacting free shear layers behind the step. The growth of the vortices and the propagation of the flamer were intimately linked. Vortex pairing was observed to be one of the mechanisms for introduction of fresh reactants into the shear layer and growth of the shear layer. Probe composition measurements of the flame showed that, in the recirculation zone, the reaction was above 99 percent complete, CO and unburnt hydrocarbons were above the equilibrium level NO sub x concentration was far below the equilibrium level and NO2 comprised a negligible fraction of NO sub x
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