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20060101BuchDiscretization methods with analytical solutions for a convectiondiffusiondispersionreactionequation and applications in 2D and 3D for wastescenarios In this part we describe the numerical methods and the results for our discretization methods for system of convectiondiffusiondispersionreaction equation. The motivation came for the simulation of a scenario of a ...

20110811BuchDiscretization methods with analytical solutions for a convectionreaction equation with higherorder discretizations We introduce an improved secondorder discretization method for the convectionreaction equation by combining analytical and numerical solutions. The method is derived from Godunov's scheme, see [Godunov 1959] and [Leveque ...

20060101BuchDiscretizationOptimization Methods for Nonlinear Elliptic Optimal Control Problems with State Constraints We consider an optimal control problem described by a second order elliptic boundary value problem, jointly nonlinear in the state and control, with control and state constraints, where the state constraints and cost ...

20060101BuchDiscretizationOptimization Methods for Nonlinear Elliptic Relaxed Optimal Control Problems with State Constraints. We consider an optimal control problem described by a second order elliptic boundary value problem, jointly nonlinear in the state and control with high monotone nonlinearity in the state, with control and state constraints, ...

20060101BuchDiscretizationOptimization Methods for Nonlinear Parabolic Relaxed Optimal Control Problems with State Constraints We consider an optimal control problem described by a semilinear parabolic partial differential equation, with control and state constraints, where the state constraints and cost involve also the state gradient. Since this ...

19971027BuchDuality Construction of Moduli Spaces

20051104BuchDuality gaps in nonconvex stochastic optimization We consider multistage stochastic optimization models. Logical or integrality constraints, frequently present in optimization models, limit the application of powerful convex analysis tools. Different Lagrangian relaxation ...

19980130BuchEffective solutions of Clebsch and C. Neumann systems We solve in Riemann theta functions the classical Clebsch system and its particular case  the C. Neumann system. Going from a new Lax representation (with rational parameter) we work out the solutions. Separately, using ...

20110811BuchEfficient covariance estimation for asynchronous noisy highfrequency data We focus on estimating the integrated covariance of logprice processes in the presence of market microstructure noise. We construct an efficient unbiased estimator for the quadratic covariation of two Itô processes in the ...

19980715BuchEfficient Reduction on the Jacobian Variety of Picard curves In this paper, a system of coordinates for the elements on the Jacobian Variety of Picard curves is presented. These coordinates possess a nice geometric interpretation and provide us with an unifying environment to obtain ...

20000106BuchEquations for Polar Varieties and Efficient Real Elimination Let $V_0$ be a smooth and compact real variety given by a reduced regular sequence of polynomials $f_1,..., f_p$. This paper is devoted to the algorithmic problem of finding efficiently for each connected component of $V_0$ ...

20051026BuchEquilibrium in abstract economies without the lower semicontinuity of the constraint maps We use graph convergence of set valued maps to show the existence of an equilibrium for an abstract economy without assuming the lower semi continuity of the constraint maps.

20110920BuchError Control in h and hpadaptive FEM for Signorini's Problem This paper presents a posteriori finite element error estimates for Signorini’s problem. The discretization is based on a mixed variational formulation proposed by Haslinger et al. which is extended to higherorder finite ...

20110811BuchError Controlled Local Resolution of Evolving Interfaces for Generalized CahnHilliard Equations For phase field equations of generalized CahnHilliard type, we present an a posteriori error analysis that is robust with respect to a small interface length scale which enters the model as a regularizing parameter. By ...

20051102BuchError Reduction And Convergence For An Adaptive Mixed Finite Element Method An adaptive mixed finite element method (AMFEM) is designed to guarantee an error reduction, also known as saturation property: After each refinement step, the error for the fine mesh is strictly smaller than the error for ...

20110920BuchEstimation of the characteristics of a Lévy process observed at arbitrary frequency

20110920BuchEstimator competition for Poisson problems

20051111BuchEvaluation of the epiconvergence The paper presents an equivalent characterization of the epiconvergence of lower semicontinuous functions. The proposed ‘measures’ naturally estimate the distance between optimal values of two optimization programs. A ...

20090702BuchExistence of turbulent weak solutions to the generalized NavierStokes equations in exterior domains and large time behaviour Let $\Omega$ be an exterior domain in $\R^n\,(n=2,3,4)$ , with boundary being not necessarily smooth. For any initial velocity ${\bf u}_0\in L^2(\Omega)^n$ such that $\nabla\cdot {\bf u}_0=0$ (in sense of distribution) and ...

20051116BuchEXTRAordinary differential equations