503 research outputs found
Baryon stopping and saturation physics in relativistic collisions
We investigate baryon transport in relativistic heavy-ion collisions at
energies reached at the CERN Super Proton Synchrotron, BNL Relativistic
Heavy-Ion Collider (RHIC), and CERN LHC in the model of saturation. An
analytical scaling law is derived within the color glass condensate framework
based on small-coupling QCD. Transverse momentum spectra, net-baryon rapidity
distributions and their energy, mass and centrality dependences are well
described. In a comparison with RHIC data in Au + Au collisions at sqrt (s_NN)
= 62.4 GeV and 200 GeV, the gradual approach to the gluon saturation regime is
investigated, and limits for the saturation-scale exponent are determined.
Predictions for net-baryon rapidity spectra and the mean rapidity loss in
central Pb + Pb collisions at LHC energies of sqrt (s_NN) = 5.52 TeV are made.Comment: 11 pages, 10 Figures; improved figure inscriptions, corrected typos,
minor changes in text/titl
An integrable modification of the critical Chalker-Coddington network model
We consider the Chalker-Coddington network model for the Integer Quantum Hall
Effect, and examine the possibility of solving it exactly. In the
supersymmetric path integral framework, we introduce a truncation procedure,
leading to a series of well-defined two-dimensional loop models, with two loop
flavours. In the phase diagram of the first-order truncated model, we identify
four integrable branches related to the dilute Birman-Wenzl-Murakami
braid-monoid algebra, and parameterised by the loop fugacity . In the
continuum limit, two of these branches (1,2) are described by a pair of
decoupled copies of a Coulomb-Gas theory, whereas the other two branches (3,4)
couple the two loop flavours, and relate to an Wess-Zumino-Witten (WZW) coset model for the particular values where is a positive integer. The truncated
Chalker-Coddington model is the point of branch 4. By numerical
diagonalisation, we find that its universality class is neither an analytic
continuation of the WZW coset, nor the universality class of the original
Chalker-Coddington model. It constitutes rather an integrable, critical
approximation to the latter.Comment: 34 pages, 18 figures, 3 appendice
User centered neuro-fuzzy energy management through semantic-based optimization
This paper presents a cloud-based building energy management system, underpinned by semantic middleware, that integrates an enhanced sensor network with advanced analytics, accessible through an intuitive Web-based user interface. The proposed solution is described in terms of its three key layers: 1) user interface; 2) intelligence; and 3) interoperability. The system’s intelligence is derived from simulation-based optimized rules, historical sensor data mining, and a fuzzy reasoner. The solution enables interoperability through a semantic knowledge base, which also contributes intelligence through reasoning and inference abilities, and which are enhanced through intelligent rules. Finally, building energy performance monitoring is delivered alongside optimized rule suggestions and a negotiation process in a 3-D Web-based interface using WebGL. The solution has been validated in a real pilot building to illustrate the strength of the approach, where it has shown over 25% energy savings. The relevance of this paper in the field is discussed, and it is argued that the proposed solution is mature enough for testing across further buildings
Anisotropic nonlinear elasticity in a spherical bead pack: influence of the fabric anisotropy
Stress-strain measurements and ultrasound propagation experiments in glass
bead packs have been simultaneously conducted to characterize the
stress-induced anisotropy under uniaxial loading. These measurements, realized
respectively with finite and incremental deformations of the granular assembly,
are analyzed within the framework of the effective medium theory based on the
Hertz-Mindlin contact theory. Our work shows that both compressional and shear
wave velocities and consequently the incremental elastic moduli agree fairly
well with the effective medium model by Johnson et al. [J. Appl. Mech. 65, 380
(1998)], but the anisotropic stress ratio resulting from finite deformation
does not at all. As indicated by numerical simulations, the discrepancy may
arise from the fact that the model doesn't properly allow the grains to relax
from the affine motion approximation. Here we find that the interaction nature
at the grain contact could also play a crucial role for the relevant prediction
by the model; indeed, such discrepancy can be significantly reduced if the
frictional resistance between grains is removed. Another main experimental
finding is the influence of the inherent anisotropy of granular packs, realized
by different protocols of the sample preparation. Our results reveal that
compressional waves are more sensitive to the stress-induced anisotropy,
whereas the shear waves are more sensitive to the fabric anisotropy, not being
accounted in analytical effective medium models.Comment: 9 pages, 8 figure
Basic and Advanced features of IPv6 Over C2C NET
The GeoNet project will significantly contribute to vehicle communication by implementing a reference specification of a geographic addressing and routing pro- tocol with support for IPv6 to be used to deliver safety messages between cars but also between cars and the roadside infrastructure within a designated destination area. Geographic addressing and routing is a networking mechanism distributing the information to nodes within a designated destination area. A novel routing pro- tocol (C2C NET) is in charge of information dissemination over multiple hops until every vehicle has received this information within the destination area. This docu- ment mentions about basic and advanced features of IPv6 over C2C NET. First, we discover the missing features in current specification of C2C NET and shows some solutions. Second, specification of IPv6 over C2C NET are described and implemen- tation example is investigated in Linux system. Third, we propose advance features such as route optimization, multihoming and simultaneous utilization of NEMO and C2C NET V2V mode
Power Sharing in Three-level NPC Inverter based Three-Phase Four-Wire Islanding Microgrids with Unbalanced Loads
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