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161.
Thermal and dielectric loss properties of Na3PO4-Pb3(PO4BiPO4 (Na2O-PbO-Bi2O3-P2O5) phosphate glasses, have been studied by the differential scanning calorimetry (DSC) and electrical factor loss (tgδ) measurements. Experiments have been carried out from ambient temperature to 500°C and show a strong influence of sodium ions on Tg and tgδ. 相似文献
162.
This paper deals with spectral theory of a new class of neutron transport operators involving collision operators of the form \(K=K_{i}+K_{e}\) where \(K_{i}\) (resp. \(K_{e}\)) describes the inelastic (resp. elastic) collisions of neutrons with the host material. We give a fine analysis of their asymptotic point spectra for isotropic space homogeneous cross sections in bounded geometries. We provide a new formalism relying on spectral analysis of some non compact symmetrizable operators arising in transport theory. Additional results on essential spectra are also given. 相似文献
163.
In the finite dimensional setting, we investigate the existence of viscosity subsolutions of Hamilton–Jacobi–Bellman equations related to control problems subject to evolution inclusions governed by time-dependent maximal monotone operators with Young measures. 相似文献
164.
Mustapha Djeddou Rafik Khelladi Mustapha Benssalah 《AEUE-International Journal of Electronics and Communications》2013,67(3):256-262
In this paper, we propose an improved anti-collision technique based on the binary search algorithm. The improvement is achieved thanks to the manner of the requests’ building. This latter reduces considerably the responding tag's numbers and therefore, decreases the probability of bit's collision. Further, the algorithm provides a noticeable advantage for the length of transmitted binary data compared against basic binary search and dynamic binary search algorithms. Besides, it provides same performance in terms of average request's number making the identification process faster, and the expose time of information is then reduced. 相似文献
165.
Sami Mustapha 《Journal of Theoretical Probability》2006,19(4):773-787
It is shown in this paper that the transition kernels corresponding to simple random walks on certain unimodular solvable
p-adic groups admit upper Gaussian estimates.
相似文献
166.
Mustapha Mokhtar-Kharroubi 《Positivity》2006,10(2):231-249
We deal with a general streaming semigroup arising in transport theory. We show that in general such a semigroup has a direct
decomposition into three simpler semigroups one of which extends to a group. A general spectral theory of them is given and
is partly derived from that of a class of positive semigroups on Banach lattices. 相似文献
167.
Mohammed Debiane Christian Kharif Mustapha Amaouche 《European Journal of Mechanics - B/Fluids》2000,19(6):855
This paper presents a method for the calculation of steady periodic capillary-gravity waves on water of arbitrary uniform depth. The method developed by Debiane and Kharif in 1997 for infinite depth is extended to finite depth. The water-wave problem is reduced to a system of nonlinear algebraic equations which is solved using Newton's method. For the resonant configurations, the method does not suffer from the Wilton's failures and is valid for all depths. In addition, it is shown that the method allows the computation of solitary waves and generalized solitary waves. 相似文献
168.
Mustapha Lahyane 《Journal of Pure and Applied Algebra》2010,214(7):1217-1240
We give a numerical criterion for ensuring the finite generation of the effective monoid of the surfaces obtained by a blowing-up of the projective plane at the supports of zero dimensional subschemes assuming that these are contained in a degenerate cubic. Furthermore, this criterion also ensures the regularity of any numerically effective divisor on these surfaces. Thus the dimension of any complete linear system is computed. On the other hand, in particular and among these surfaces, we obtain ringed rational surfaces with very large Picard numbers and with only finitely many integral curves of strictly negative self-intersection. These negative integral curves except two (−1)-curves are all contained in the support of an anticanonical divisor. Thus almost all the geometry of such surfaces is concentrated in the anticanonical class. 相似文献
169.
170.
Mustapha El Jarroudi 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2010,61(6):1053-1083
We study the homogenization of an incompressible viscous flow in a porous medium with double porosity. We derive a macroscopic model with local Navier–Stokes system in the large cavities, Darcy law in the thinner porous rock, and a contact law between the two. We use Γ-convergence methods associated with multi-scale convergence notions in order to get this limit law. We exhibit a critical ratio between the two scales of the pores. 相似文献