6,357 research outputs found
Extensible Automated Constraint Modelling
In constraint solving, a critical bottleneck is the formulationof an effective constraint model of a given problem. The CONJURE system described in this paper, a substantial step forward over prototype versions of CONJURE previously reported, makes a valuable contribution to the automation of constraint modelling by automatically producing constraint models from their specifications in the abstract constraint specification language ESSENCE. A set of rules is used to refine an abstract specification into a concrete constraint model. We demonstrate that this set of rules is readily extensible to increase the space of possible constraint models CONJURE can produce. Our empirical results confirm that CONJURE can reproduce successfully the kernels of the constraint models of 32 benchmark problems found in the literature
Approximation in Smirnov-Orlicz classes
We use the approximation properties of the Faber polynomials to obtain some direct theorems of the polynomial approximation in Smirnov-Orlicz classes
Measurements of the Rate Capability of Various Resistive Plate Chambers
Resistive Plate Chambers (RPCs) exhibit a significant loss of efficiency for
the detection of particles, when subjected to high particle fluxes. This rate
limitation is related to the usually high resistivity of the resistive plates
used in their construction. This paper reports on measurements of the
performance of three different glass RPC designs featuring a different total
resistance of the resistive plates. The measurements were performed with 120
GeV protons at varying beam intensitie
Embryonic stem cell virus, a recombinant murine retrovirus with expression in embryonic stem cells.
Quartz Cherenkov Counters for Fast Timing: QUARTIC
We have developed particle detectors based on fused silica (quartz) Cherenkov
radiators read out with micro-channel plate photomultipliers (MCP-PMTs) or
silicon photomultipliers (SiPMs) for high precision timing (Sigma(t) about
10-15 ps). One application is to measure the times of small angle protons from
exclusive reactions, e.g. p + p - p + H + p, at the Large Hadron Collider, LHC.
They may also be used to measure directional particle fluxes close to external
or stored beams. The detectors have small areas (square cm), but need to be
active very close (a few mm) to the intense LHC beam, and so must be radiation
hard and nearly edgeless. We present results of tests of detectors with quartz
bars inclined at the Cherenkov angle, and with bars in the form of an "L" (with
a 90 degree corner). We also describe a possible design for a fast timing
hodoscope with elements of a few square mm.Comment: 24 pages, 14 figure
Project PROMETHEUS: Design and Construction of a Radio Frequency Quadrupole at TAEK
The PROMETHEUS Project is ongoing for the design and development of a 4-vane
radio frequency quadrupole (RFQ) together with its H+ ion source, a low energy
beam transport (LEBT) line and diagnostics section. The main goal of the
project is to achieve the acceleration of the low energy ions up to 1.5 MeV by
an RFQ (352 MHz) shorter than 2 meter. A plasma ion source is being developed
to produce a 20 keV, 1 mA H+ beam. Simulation results for ion source,
transmission and beam dynamics are presented together with analytical studies
performed with newly developed RFQ design code DEMIRCI. Simulation results
shows that a beam transmission 99% could be achieved at 1.7 m downstream
reaching an energy of 1.5 MeV. As the first phase an Aluminum RFQ prototype,
the so-called cold model, will be built for low power RF characterization. In
this contribution the status of the project, design considerations, simulation
results, the various diagnostics techniques and RFQ manufacturing issues are
discussed.Comment: 4 pages, 8 figures, Proceedings of the 2nd International Beam
Instrumentation Conference 2013 (IBIC'13), 16-19 Sep 2013, WEPC02, p. 65
Development of a supervisory controller for residential energy management problems
In recent years, the infrastructure that supplies energy to residential areas has started to evolve into a multi-source system, just like in automotive industry in which hybrid electric vehicles (HEVs) have been replacing conventional gasoline vehicles. Multi energy source systems considered as a potential solution for carbon emission problems despite their challenges in their operation due to increased complexity. In this paper, a control design approach successfully applied in the automotive industry is used to solve a residential energy management problem. First, a dynamic programming method is applied to obtain optimal control actions for the representative demand profiles and then by using these results, a causal supervisory controller is developed. It is found that the developed baseline controller performs 1-2% better daily in its initial form in terms of operational costs, compared to available heuristic strategies. © 2012 AACC American Automatic Control Council)
Treatment-Resistant Obsessive-Compulsive Disorder: Clinical and Personality Correlates
AbstractThe objective of the present study was to establish a clinical/personality profile of Turkish patients with treatment-resistant obsessive-compulsive disorder (TR-OCD). Methods. A neurocognitive/clinical test battery was administered to 17 patients with TR-OCD. Results. TR-OCD patients presented with major psychiatric syndromes (especially mood and generalized anxiety disorders) and personality disorders (particularly paranoid, avoidant, obsessive-compulsive, histrionic), and obtained higher scores on measures of core OCD symptoms (i.e., obsessional ideation, compulsive cleaning/washing, mental neutralizing), depressive symptoms, schizotypal personality features, and impulsiveness relative to normative controls. TR-OCD patients did not differ significantly from normative controls on checking, doubting, ordering, and hoarding subscales, and on measures of venturesomeness and empathy. Conclusions. Lack of insight, suspiciousness, and rigidity associated with schizotypal, paranoid, and obsessive-compulsive personality features may have contributed to treatment failure
Tkachenko modes as sources of quasiperiodic pulsar spin variations
We study the long wavelength shear modes (Tkachenko waves) of triangular
lattices of singly quantized vortices in neutron star interiors taking into
account the mutual friction between the superfluid and the normal fluid and the
shear viscosity of the normal fluid. The set of Tkachenko modes that propagate
in the plane orthogonal to the spin vector are weakly damped if the coupling
between the superfluid and normal fluid is small. In strong coupling, their
oscillation frequencies are lower and are undamped for small and moderate shear
viscosities. The periods of these modes are consistent with the observed
~100-1000 day variations in spin of PSR 1828-11.Comment: 7 pages, 3 figures, uses RevTex, v2: added discussion/references,
matches published versio
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