Results 11 to 20 of about 3,216 (210)
Ibn Al-Haitham Journal for Pure and Applied Sciences, 2022 This paper aims to study the quaternary classical continuous optimal control problem consisting of the quaternary nonlinear parabolic boundary value problem, the cost function, and the equality and inequality constraints on the state and the control ...
jamil Amir Al-Hawasy +1 more
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Continuity of the Spectrum of a Field of Self-Adjoint Operators [PDF]
Annales Henri Poincaré, 2016 Given a family of self-adjoint operators $(A_t)_{t\in T}$ indexed by a parameter $t$ in some topological space $T$, necessary and sufficient conditions are given for the spectrum $σ(A_t)$ to be Vietoris continuous with respect to $t$. Equivalently the boundaries and the gap edges are continuous in $t$. If $(T,d)$ is a complete metric space with metric $
Beckus, Siegfried, Bellissard, Jean
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Adjoint based state estimation of compressible flow in porous media
Petroleum, 2021 In this paper, we study the state estimation of compressible single phase flow in compressible porous media. The initial pressure distribution is estimated according to discrete adjoint approach based on the collected well pressure data.
Yanbin Sun, Zhibin Liu, Yanjie Hu
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Continuous and discrete adjoints to the Euler equations for fluids [PDF]
International Journal for Numerical Methods in Fluids, 2011 SUMMARYAdjoints are used in optimization to speed‐up computations, simplify optimality conditions or compute sensitivities. Because time is reversed in adjoint equations with first‐order time derivatives, boundary conditions, and transmission conditions through shocks can be difficult to understand.
Frédéric Alauzet, Olivier Pironneau
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Continuous Adjoint Method for Unstructured Grids [PDF]
AIAA Journal, 2008 Adjoint-based shape optimization methods have proven to be computationally efficient for aerodynamic problems. The majority of the studies on adjoint methods have used structured grids to discretize the computational domain. Because of the potential advantages of unstructured grids for complex configurations, in this study we have developed and ...
Antony Jameson +2 more
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International Journal of Turbomachinery, Propulsion and Power, 2021 This paper presents an adjoint-based shape optimization framework and its demonstration in a conjugate heat transfer problem in a turbine blading. The gradient of the objective function is computed based on the continuous adjoint method, which also ...
Xenofon Trompoukis +4 more
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Adjoint Optimization for Vehicle External Aerodynamics
International Journal of Automotive Engineering, 2016 Adjoint optimization is an exciting and fast growing field that has many applications in the automotive industry. We focus on the usage of adjoint for the optimization of aerodynamic performance.
Karpouzas Georgios K. +5 more
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Adjoint and Direct Characteristic Equations for Two-Dimensional Compressible Euler Flows
Aerospace, 2023 The method of characteristics is a classical method for gaining understanding in the solution of a partial differential equation. It has recently been applied to the adjoint equations of the 2D steady-state Euler equations and the first goal of this ...
Kevin Ancourt +2 more
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Aeroacoustic and Aerodynamic Adjoint-Based Shape Optimization of an Axisymmetric Aero-Engine Intake
Aerospace, 2023 A continuous adjoint-based aeroacoustic optimization, based on a hybrid model including the Ffowcs Williams–Hawkings (FW–H) acoustic analogy, to account for the multidisciplinary design of aero-engine intakes with an axisymmetric geometry, is presented ...
Morteza Monfaredi +4 more
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Derivation of the Adjoint Drift Flux Equations for Multiphase Flow
Fluids, 2020 The continuous adjoint approach is a technique for calculating the sensitivity of a flow to changes in input parameters, most commonly changes of geometry.
Shenan Grossberg +2 more
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