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61.
Auslender, Cominetti and Haddou have studied, in the convex case, a new family of penalty/barrier functions. In this paper, we analyze the asymptotic behavior of augmented penalty algorithms using those penalty functions under the usual second order sufficient optimality conditions, and present order of convergence results (superlinear convergence with order of convergence 4/3). Those results are related to the analysis of pure penalty algorithms, as well as augmented penalty using a quadratic penalty function. Limited numerical examples are presented to appreciate the practical impact of this local asymptotic analysis.This research was partially supported by NSERC grant OGP0005491 相似文献
62.
We introduce the set of bicomplex numbers
which is a commutative ring with zero divisors defined by
where
We present the conjugates and the moduli associated with the bicomplex numbers. Then we study the bicomplex Schr?dinger equation
and found the continuity equations. The discrete symmetries of the system of equations describing the bicomplex Schr?dinger
equation are obtained. Finally, we study the bicomplex Born formulas under the discrete symmetries. We obtain the standard
Born’s formula for the class of bicomplex wave functions having a null hyperbolic angle. 相似文献
63.
Pavel Bedrikovetsky Fernando D. Siqueira Claudio A. Furtado Antonio Luiz S. Souza 《Transport in Porous Media》2011,86(2):353-383
Particle detachment from the rock during suspension transport in porous media was widely observed in laboratory corefloods
and for flows in natural reservoirs. A new mathematical model for detachment of particles is based on mechanical equilibrium
of a particle positioned on the internal cake or matrix surface in the pore space. The torque balance of drag, electrostatic,
lifting and gravity forces, acting on the particle from the matrix and the moving fluid, is considered. The torque balance
determines maximum retention concentration during the particle capture. The particle torque equilibrium is determined by the
dimensionless ratio between the drag and normal forces acting on the particle. The maximum retention function of the dimensionless
ratio (dislodging number) closes system of governing equations for colloid transport with particle release. One-dimensional
problem of coreflooding by suspension accounting for limited particle retention, controlled by the torque sum, allows for
exact solution under the assumptions of constant filtration coefficient and porosity. The explicit formulae permit the calculation
of the model parameters (maximum retention concentration, filtration and formation damage coefficients) from the history of
the pressure drop across the core during suspension injection. The values for maximum retention concentration, as obtained
from two coreflood tests, have been matched with those calculated by the torque balance on the micro scale. 相似文献
64.
Bruno Farias Jilvan Lemos de Melo Claudio Furtado 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2014,68(4):1-5
New data for positronium beam production efficiency are presented. As a converter of positrons to forward-going positronium, O2 has been found to be as good as CO2 from ~250 to 400 eV. Preliminary data is also presented for the production efficiency from Ar at 2.8 eV. 相似文献
65.
66.
Carolina Silva Marques Anthony J. Burke Olívia R. Furtado 《Tetrahedron letters》2007,48(45):7957-7960
This Letter describes an expeditious regiospecific and stereoselective approach to tertiary α-hydroxyesters via a simple one pot tandem catalytic oxidation/benzilic ester rearrangement of acyclic α-hydroxyketone substrates. Mechanistic studies confirming the regioselective nature of this reaction are discussed, including some insights into the nature of the stereoselectivity encountered in this reaction. 相似文献
67.
68.
R.S. de Biasi C.A. Taft N.C. Furtado 《Journal of magnetism and magnetic materials》1981,23(2):211-213
ESR measurements have been performed in the linear chain entiferromagnet RbFeS2 in the temperature range 100–380 K. Both the resonance field and the linewidth are found to change steadily as the temperature is increased, without any discontinuity or singularity at the transition temperature TN = 185 K. The experimental results are compared with available data on other one-dimensional compounds. 相似文献
69.
The relativistic quantum dynamics of an electrically charged particle subject to the Klein–Gordon oscillator and the Coulomb potential is investigated. By searching for relativistic bound states, a particular quantum effect can be observed: a dependence of the angular frequency of the Klein–Gordon oscillator on the quantum numbers of the system. The meaning of this behaviour of the angular frequency is that only some specific values of the angular frequency of the Klein–Gordon oscillator are permitted in order to obtain bound state solutions. As an example, we obtain both the angular frequency and the energy level associated with the ground state of the relativistic system. Further, we analyse the behaviour of a relativistic position-dependent mass particle subject to the Klein–Gordon oscillator and the Coulomb potential. 相似文献
70.
In this paper we study the relativistic quantum dynamics of a massless fermion confined in a quantum ring. We use a model of confining potential and introduce the interaction via Dirac oscillator coupling, which provides ring confinement for massless Dirac fermions. The energy levels and corresponding eigenfunctions for this model in graphene layer in the presence of Aharonov–Bohm flux in the centre of the ring and the expression for persistent current in this model are derived. We also investigate the model for quantum ring in graphene layer in the presence of a disclination and a magnetic flux. The energy spectrum and wave function are obtained exactly for this case. We see that the persistent current depends on parameters characterizing the topological defect. 相似文献