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This paper presents a criterion for detecting diffuse (homogeneous) instabilities in granular soils sheared under fully drained conditions. The criterion is based on bifurcation theory and applied to elasto-plasticity by allowing multiple incremental solutions in elasto-plastic soils, physically losing controllability of stress boundary conditions. Drained diffuse instabilities are poorly understood, and are induced by kinematic modes different from those observed in shear bands and liquefaction instabilities. Unlike shear bands, diffuse instabilities occur under fairly homogenous deformation modes and, unlike liquefaction, drained instabilities are not generated by the excess pore pressures. Recent experiments under drained constant shear report sudden homogeneous instabilities in samples of relatively dense and loose sands. The criterion presented in this paper is used in conjunction with an elasto-plasticity model for sands to predict and explain these reported drained instabilities. From a practical standpoint, these developments serve to expand the repertoire of potential instabilities that occur well before failure, and which have been reported in case studies of puzzling slope instability failures under fully drained conditions. [ABSTRACT FROM AUTHOR]

This article deals with an inverse problem concerning the identification of the heat exchange coefficient H (assumed depending on the temperature and/or pressure) between a certain material with the external environment, when only experimental measurements of the temperature are supposed to be known. The main difficulties are that we consider the case of functions H depending on the solution of the state equation and we use experimental data that may have errors. We develop rigorous mathematical strategies for this identification. We separately consider pressure and temperature dependence and, in both cases, we set several scenarios for the inverse problem. For each scenario, we know the initial and ambient temperatures, we identify function H through different methods and we obtain error bounds in adequate norms (uniform and square integrable). Finally, we perform numerical tests in order to compare the results obtained with these algorithms and with some classical regularization algorithms. [ABSTRACT FROM AUTHOR]

This article is concerned with the numerical solution of multiobjective control problems associated with linear partial differential equations. More precisely, for such problems, we look for the Nash equilibrium, which is the solution to a noncooperative game. First, we study the continuous case. Then, to compute the solution of the problem, we combine finite-difference methods for the time discretization, finite-element methods for the space discretization, and conjugate-gradient algorithms for the iterative solution of the discrete control problems. Finally, we apply the above methodology to the solution of several tests problems. [ABSTRACT FROM AUTHOR]

This article is concerned with the numerical solution of multiobjective control problems associated with nonlinear partial differential equations and more precisely the Burgers equation. For this kind of problems, we look for the Nash equilibrium, which is the solution to a noncooperative game. To compute the solution of the problem, we use a combination of finite-difference methods for the time discretization, finite-element methods for the space discretization, and a quasi-Newton BFGS algorithm for the iterative solution of the discrete control problem. Finally, we apply the above methodology to the solution of several tests problems. To be able to compare our results with existing results in the literature, we discuss first a single-objective control problem, already investigated by other authors. Finally, we discuss the multiobjective case. [ABSTRACT FROM AUTHOR]

Abstract. We prove the approximate controllability of several nonlinear parabolic boundary-value problems by means of two different methods: the first one can be called a Cancellation method and the second one uses the Kakutani fixed-point theorem. Key Words. Approximate controllability, Semilinear parabolic boundary-value problems, Interior or boundary controls. [ABSTRACT FROM AUTHOR]

Studies the mapping of the porcine peroxisome proliferator activated receptor alpha gene to chromosome 5. Primer sequences; Polymerase chain reaction conditions; Genetic polymorphism and Mendelian inheritance; Chromosomal location.

Studies the assignment of the porcine peptide YY gene to chromosome 12. Primer sequences; Polymerase chain reaction conditions; Genetic polymorphism and Mendelian inheritance; Chromosomal location.