Search results for "DISTRIBUTIONS"
showing 10 items of 214 documents
Interactions, spillovers de connaissance et croissance des économies modernes. Faut-il préférer la globalisation ou la proximité géographique ?
2009
Globalisation and metropolisation in modern economies induce some locational strategies of knowledge based activities towards cities and deeply increase trade and move of ideas across cities. In that context, we study the way knowledge spillovers have influenced the economic growth of 82 European Metropolises over the 1990-2005 period. We model knowledge spillovers across cities according to three specific interaction patterns depending either on geography or on global advanced services or thought a combination of these patterns. We show that the mixed pattern matters the best for economic growth of cities in Europe.
Ion beam intensity and phase space measurement techniques for ion sources.
2022
Ion sources produce beams used in accelerators and other applications. Both development and use of ion sources need beam diagnostics to probe the plasma processes and beam formation for optimization purposes and to produce beam parameters needed for transport tuning. These diagnostics include beam intensity measurements usually carried out with Faraday cups or inductive pickups, magnetic separation, profile measurements with scintillation screens and wires, and phase space measurements with different types of emittance scanners. peerReviewed
Orbital angular momentum parton distributions in quark models
1999
At the low energy, {\sl hadronic}, scale we calculate Orbital Angular Momentum (OAM) twist-two parton distributions for the relativistic MIT bag model and for non-relativistic quark models. We reach the scale of the data by leading order evolution in perturbative QCD. We confirm that the contribution of quarks and gluons OAM to the nucleon spin grows with $Q^2$, and it can be relevant at the experimental scale, even if it is negligible at the hadronic scale, irrespective of the model used. The sign and shape of the quark OAM distribution at high $Q^2$ may depend strongly on the relative size of the OAM and spin distributions at the hadronic scale. Sizeable quark OAM distributions at the had…
Flamingo studies: a general introduction.
2017
28 pages; International audience; Flamingos are among the most amazing birds in the world. The first part of this chapter provides a general introduction to the various extant species of flamingos, including their physical descriptions, unique characteristics, numbers in the wild, and geographical distributions. The second part depicts a brief history of the discovery and scientific study of flamingos, from the earlier accounts dating from the 16th century to the development of the first long-term studies of banded populations in the second half of the 20th century. The third and final part of this chapter offers some perspectives for future research.
The paradox of endogenous poverty line in the poverty indices
2007
february 23-25, 2007; When measuring poverty, the poverty line is considered to be relatively determined as a percentage of the median income or as a percentage of the average income so as to allow international comparisons. The poverty line relative to the median income may be described as endogenous in contrast with the poverty line relative to the average income which may be described as exogenous because it is independent of the normalized distribution of incomes. As the existing literature is focused on the properties of the indices but not on the respective interest of the endogenous and exogenous poverty lines, this paper compares the two definitions of the relative poverty. The Rela…
Pseudorapidity and transverse-momentum distributions of charged particles in proton–proton collisions at √s = 13 TeV
2016
The pseudorapidity (η) and transverse-momentum (pT) distributions of charged particles produced in proton–proton collisions are measured at the centre-of-mass energy √s = 13 TeV. The pseudorapidity distribution in |η| < 1.8 is reported for inelastic events and for events with at least one charged particle in |η| < 1. The pseudorapidity density of charged particles produced in the pseudorapidity region |η| < 0.5 is 5.31 ± 0.18 and 6.46 ± 0.19 for the two event classes, respectively. The transverse-momentum distribution of charged particles is measured in the range 0.15 < pT < 20 GeV/c and |η| < 0.8 for events with at least one charged particle in |η| < 1. The evolution of the transverse mome…
ESTIMATING RAINFALL EROSIVITY BY DROP SIZE DISTRIBUTIONS
Water soil erosion is a process of detachment and transport of soil particles due to rainfall and runoff and it is the main cause of the modeling of extended portions of the earth's surface. The acceleration of the process through anthropogenic perturbation has severe impacts on soil and environmental quality. Soil erosion above a certain level will reduce soil productivity over the long haul. It exposes subsoil, which has often poor qualities for crop establishment and growth, and it can lead to stand loss by sediment deposition. A fundamental property of rainfall for understanding how it is made up is the raindrop size distribution (DSD). The knowledge of the raindrop size distribution at…
Jet fragmentation transverse momentum distributions in pp and p-Pb collisions at √s, √sNN = 5.02 TeV
2021
Jet fragmentation transverse momentum (jT) distributions are measured in proton-proton (pp) and proton-lead (p-Pb) collisions at √sNN = 5.02 TeV with the ALICE experiment at the LHC. Jets are reconstructed with the ALICE tracking detectors and electromagnetic calorimeter using the anti-kT algorithm with resolution parameter R = 0.4 in the pseudorapidity range |η| < 0.25. The jT values are calculated for charged particles inside a fixed cone with a radius R = 0.4 around the reconstructed jet axis. The measured jT distributions are compared with a variety of parton-shower models. Herwig and Pythia 8 based models describe the data well for the higher jT region, while they underestimate the low…
Charged jet cross sections and properties in proton-proton collisions at $\sqrt{s}=7$ TeV
2015
The differential charged jet cross sections, jet fragmentation distributions, and jet shapes are measured in minimum bias proton-proton collisions at centre-of-mass energy $\sqrt{s}=7$ TeV using the ALICE detector at the LHC. Jets are reconstructed from charged particle momenta in the mid-rapidity region using the sequential recombination $k_{\rm T}$ and anti-$k_{\rm T}$ as well as the SISCone jet finding algorithms with several resolution parameters in the range $R=0.2$ to $0.6$. Differential jet production cross sections measured with the three jet finders are in agreement in the transverse momentum ($p_{\rm T}$) interval $20<p_{\rm T}^{\rm jet,ch}<100$ GeV/$c$. They are also consistent w…
Euclid preparation: XI. Mean redshift determination from galaxy redshift probabilities for cosmic shear tomography
2021
Ilbert, O., et al. (Euclid Collaboration)