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Wireless Networks - In order to satisfy the delay requirements of telecommunication systems, in this paper, we present a cooperative network with the short packet transmission in the Rayleigh... 相似文献
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Ronald I. Becker Isabella Lari Andrea Scozzari Giovanni Storchi 《Annals of Operations Research》2007,150(1):65-78
In this paper we consider the location of a path shaped facility on a grid graph. In the literature this problem was extensively
studied on particular classes of graphs as trees or series-parallel graphs. We consider here the problem of finding a path
which minimizes the sum of the (shortest) distances from it to the other vertices of the grid, where the path is also subject
to an additional constraint that takes the form either of the length of the path or of the cardinality. We study the complexity
of these problems and we find two polynomial time algorithms for two special cases, with time complexity of O(n) and O(nℓ) respectively, where n is the number of vertices of the grid and ℓ is the cardinality of the path to be located.
The literature about locating dimensional facilities distinguishes between the location of extensive facilities in continuous
spaces and network facility location. We will show that the problems presented here have a close connection with continuous
dimensional facility problems, so that the procedures provided can also be useful for solving some open problems of dimensional
facilities location in the continuous case. 相似文献
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U. De Sanctis T. Lari S. Montesano C. Troncon 《The European Physical Journal C - Particles and Fields》2007,52(3):743-758
This paper discusses the potential of ATLAS to study supersymmetry in the “focus point” region of the parameter space of mSUGRA
models. The potential to discover a deviation from standard model expectations with the first few fb-1 of LHC data was studied using the parametrized simulation of the ATLAS detector. Several signatures were considered, involving
hard jets, large missing energy, and either b-tagged jets, opposite-sign isolated electron or muon pairs, or top quarks reconstructed
exploiting their fully-hadronic decays. With only 1 fb-1 of data each of these signatures may allow for observing an excess of events over standard model expectations with a statistical
significance exceeding five standard deviations. Furthermore, each of the two invariant mass distributions of the two leptons
produced by the and the three-body decays has a kinematic endpoint that measures the difference between the masses of the parent and daughter neutralino.
An analytical expression was derived for the shape of this distribution and was used to fit the simulated LHC data. A measurement
of the and mass differences was obtained and this information was used to constrain the MSSM parameter space. 相似文献
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In this paper we consider the Bounded Length Median Path Problem which can be defined as the problem of locating a path-shaped facility that departures from a given origin and arrives at a given destination in a network. The length of the path is assumed to be bounded by a given maximum length. At each vertex of the network (customer-point) the demand for the service is given and the cost to reach the closest service-point is computed. The objective is to minimize the sum of these costs over all the customer-points in the network. 相似文献
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Wireless Networks - We study transmission delay minimization of a wireless powered communication (WPC) system in a point-to-point scenario with one hybrid access point (HAP) and one WPC node. In... 相似文献
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In the present work, the interaction between non-gray radiation and forced convection in a laminar radiating gas flow over a recess including two backward and forward facing steps in a duct is investigated numerically. Distributions of absorption coefficients across the spectrum (50 cm?1 < η < 20,000 cm?1) are obtained from the HITRAN2008 database. The full-spectrum k-distribution method is used to account for non-gray radiation properties, while the gray radiation calculations are carried out using the Planck mean absorption coefficient. To find the divergence of radiative heat flux distribution, the radiative transfer equation is solved by the discrete ordinates method. The effects of radiation–conduction parameter, wall emissivity, scattering coefficient and recess length on heat transfer behaviors of the convection–radiation system are investigated for both gray and non-gray mediums. In addition, the results of gray medium are compared with non-gray results in order to judge if the differences between these two approaches are significant enough to justify the usage of non-gray models. Results show that for air mixture with 10 % CO2 and 20 % H2O, use of gray model for the radiative properties may cause significant errors and should be avoided. 相似文献
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A Lari MB Pitak SJ Coles GJ Rees SP Day ME Smith JV Hanna JD Wallis 《Organic & biomolecular chemistry》2012,10(38):7763-7779
The X-ray crystal structures of salts and zwitterionic Knoevenagel products from 1-dimethylamino-naphthalene-8-carbaldehyde show long N-C bonds between peri-groups which provide models for incomplete nucleophilic attack on a protonated carbonyl group and electron-deficient alkenes respectively. For the salts the N-C bonds lie in the range 1.625-1.638 ? with C-OH bonds intermediate in length between single and double bonds, while for the zwitterions the N-C bonds lie in the range 1.612-1.660 ?. The structural assignment of the former is supported by solid state (13)C and (15)N NMR studies on doubly isotopically-labelled material. Several zwitterions were converted to naphtha[1,8-bc]azepines by a mechanism involving the tertiary amino effect. 相似文献
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