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    Improvement combined with (analysis, CSP, Arithmetic analysis and Interval) of Simulations for efficient combination of two lower bound functions in (univariate,multivariate) global optimization and generalization
    (2019-12-16) CHEBBAH, MOHAMMED; Ouanes, Mohand; Zidna, Ahmed
    Univariate global optimization problems attract attention of researchers.Several methods [23] have been studied in the literature for univariate global optimization problems . Optimization in R presents the same difficulty as in Rn. Many algorithms are directed in this direction. For cutting methods in Global optimization or Optimsation gradient method in general . In this work, we propose to improve: The article submitted: ( Simulations for efficient combination of two lower bound functions in univariate global optimization. AIP Conference Proceedings 1863, 250004 (2017) ; https ://doi.org/10.1063/1.4992412, (2017). ) In this context too, we will accelerate the speed of the Algorithm for better complexity with technics (CSP, Arithmetic analysis and Interval and another). It should be noted that, we have made conclusive simulations in this direction .
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    Dynamical Properties of an Atomic Interface Between fcc Lattices
    (2019-09-17) Lekadir, Fazia; Tigrine, Rachid
    A study of the phonon contribution to the interface properties between two fcc dissimilar solids is presented. The model system is obtained by the juxtaposition of two semi-infinite harmonic fcc lattices. The interface observables are numerically calculated for different cases of masses and elastic softening to hardening, to investigate how the local dynamics can respond to many environmental microscopic changes in the field interfacial domain. The theoretical formalism using simultaneously the Green's functions and the matching method is employed to describe the dynamics of the fcc system, the complete evanescent and the propagating fields. A calculation is presented for the vibration localized states, the coherent phonon transmission and the density of states (DOS), as element of a Landauer-Büttiker type scattering matrix. The system dynamics, the phonon scattering and the transmission spectra via the interface domain between fcc lattices and the DOS are analyzed as function of the atomic masses and the elastic force constants occurring in the nanojunction zone of the model system. Our results show that the interface zone is an effective phonon splitter and suggest that its characteristics may be controlled by varying its nanometric parameters. The observed fluctuations are due to the coherent coupling between continuum and discrete states induced by the interface domain.
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    Influence of the cation force diffusion on thermal oxidation of metals
    (2019-11-19) N. Halem; Z.Halem; M. Abrudeanu; G. Petot Ervas
    The crucial role of transport processes through oxide layers has long been acknowledged in the study of metal oxidation, but the experimental results are generally analyzed taking into account observations performed at room temperatures. In the present work, we present a formal treatment, derived by use of equations of irreversible thermodynamic as a general basis, to describe the kinetics of oxide layer growth. This has allowed us to show the influence of both the cation diffusion driving force and the cation kinetic demixing within the oxidation layer.
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    Simulation Improvements (analysis, CSP, Arithmetic analysis and Interval) for efficient combination of two lower bound functions in univariate global optimization
    (2019-08-20) CHEBBAH, MOHAMMED; Ouanes, Mohand; Zidna, Ahmed
    Univariate global optimization problems attract attention of researchers.Several methods [23] have been studied in the literature for univariate global optimization problems . Optimization in R presents the same difficulty as in Rn. Many algorithms are directed in this direction. For cutting methods in Global optimization or Optimsation gradient method in general . In this work, we propose to improve: The article submitted: ( Simulations for efficient combination of two lower bound functions in univariate global optimization. AIP Conference Proceedings 1863, 250004 (2017) ; https ://doi.org/10.1063/1.4992412, (2017). ) In this context too, we will accelerate the speed of the Algorithm for better complexity with technics (CSP, Arithmetic analysis and Interval and another). It should be noted that, we have made conclusive simulations in this direction
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    A DC Algorithm for Solving Multiobjective Stochatic Problem via Exponential Utility Functions
    (2019-07-08) Kasri, Ramzi; Bellahcene, Fatima
    In this paper we suggest an algorithm for solving a multiobjective stochastic linear programming problem with normal multivariate distributions. The problem is first transformed into a deterministic multiobjective problem introducing the expected value criterion and an utility function. The obtained problem is reduced to a monobjective quadratic problem using a weighting method. This last problem is solved by DC algorithm.
Communications scientifiques internationales