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991.
H. Caines 《The European Physical Journal C - Particles and Fields》2007,49(1):297-301
The soft physics, pT<2 GeV/c, observables at both RHIC and the SPS have now been mapped out in quite specific detail. From these results there
is mounting evidence that this regime is primarily driven by the multiplicity per unit rapidity, dNch/dη. This suggests that the entropy of the system alone is the underlying driving force for many of the global observables
measured in heavy-ion collisions. That this is the case and there is an apparent independence on collision energy is surprising.
I present the evidence for this multiplicity scaling and use it to make some extremely naive predictions for the soft sector
results at the LHC. 相似文献
992.
Liquid chromatography-electrospray ionisation mass spectrometry was evaluated in the high-throughput analysis of microcystins and nodularins, cyanobacterial peptide hepatotoxins. Extracts originating from cyanobacterial strains and field material were separated on a 30 mm × 4 mm I.D. Merck Purospher STAR RP-18e column using a rapid gradient of aqueous formic acid and acetonitrile, ionised by electrospray technique and analysed on a Micromass Quattro II triple-quadrupole mass spectrometer operated in the selected ion recording (SIR) mode. The total analysis time per sample was 2.8 min corresponding to 514 samples a day. The system showed good robustness during a series of 320 repetitive injections of a field sample containing three major microcystins. 相似文献
993.
We give combinatorial proofs that certain families of differences of products of Schur functions are monomial-positive. We
show in addition that such monomial-positivity is to be expected of a large class of generating functions with combinatorial
definitions similar to Schur functions. These generating functions are defined on posets with labelled Hasse diagrams and
include for example generating functions of Stanley's (P,ω)-partitions.
T.L. was supported in part by NSF DMS-0600677. 相似文献
994.
995.
A finite volume solver for the 2D depth‐integrated harmonic hyperbolic formulation of the mild‐slope equation for wave propagation is presented and discussed. The solver is implemented on unstructured triangular meshes and the solution methodology is based upon a Godunov‐type second‐order finite volume scheme, whereby the numerical fluxes are computed using Roe's flux function. The eigensystem of the mild‐slope equations is derived and used for the construction of Roe's matrix. A formulation that updates the unknown variables in time implicitly is presented, which produces a more accurate and reliable scheme than hitherto available. Boundary conditions for different types of boundaries are also derived. The agreement of the computed results with analytical results for a range of wave propagation/transformation problems is very good, and the model is found to be virtually paraxiality‐free. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
996.
A new mechanism of pulsed laser oscillation based on ion-ion recombination is proposed. The advantages of utilizing this mechanism in a pulsed mode are considered, and the expected characteristics of the proposed lasers are estimated. 相似文献
997.
998.
A Network Simulation of High-congestion Road-traffic Flows in Cities with Marine Container Terminals
James A. Pope Terry R. Rakes Loren Paul Rees Ingrid W. M. Crouch 《The Journal of the Operational Research Society》1995,46(9):1090-1101
Port cities where marine cargo terminals are located are generally near urban areas characterized by high-congestion road traffic. Changes in cargo traffic volumes into a marine terminal, or in the surrounding traffic arteries, which carry this traffic, can significantly affect the terminal's operations. Conversely, activity at the terminal can have an impact on the traffic levels and congestion for a considerable distance from the terminal. This paper demonstrates a methodology useful for studying the impact of road traffic flows on marine container terminals located in highly congested areas. This model was developed at the request of the Virginia Center for World Trade and was used to answer three planning questions in the port of Hampton Roads, Virginia, USA-what would be the impact of: opening a new section of interstate highway, a projected doubling of container traffic at one terminal, and a daily unit train in the vicinity of another terminal. The problem was made more challenging by limited data-collection funds. None the less, the model was deemed valid by a panel of traffic experts and officials from several major state and private agencies involved in marine traffic management. The model results were subsequently a factor in two major decisions related to terminal management. 相似文献
999.
I. N. Belousov A. A. Makhnev 《Proceedings of the Steklov Institute of Mathematics》2007,257(1):S47-S60
Possible orders and subgraphs of the fixed points of a distance-regular graph with the intersection array {8, 7, 5; 1, 1, 4} are found. It is shown that such a graph is not vertex-transitive. 相似文献
1000.
We study the tangent space at a monomial point M in the Hilbert scheme that parameterizes all ideals with the same Hilbert function as M over an exterior algebra. 相似文献