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Showing 1 to 20 of 62 for “"Quasi-Newton"”.
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Quasi-Newton Methods for Nonlinear Programming
… a new class of symmetric updates for use in a quasi-Newton method for nonlinear programming. We show how these updates model the underlying nonlinear equation better than the standard symmetric updates and also how they require less overall work for large problems.
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Quasi-Newton algorithms for large scale nonlinear systems
In this work, an evaluation of a number of quasi-Newton algorithms and strategies for sparse, symmetric Hessian matrices was performed. It was shown how these quasi-Newton algorithms could be applied to the unconstrained minimization of a nonlinear function as well as a nonlinear least squares …
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Tracking on manifolds : quasi-Newton optimisation algorithms on manifolds
… such as the steepest descent algorithm, the Newton's method and the trust region algorithm have be extended to Riemannian manifolds or smooth manifolds. However, little work has been done in quasi-Newton algorithms on manifolds. In 1982, Gabay proposed a BFGS algorithm (which is a popular …
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Quasi-Newton and Multigrid Methods for Semiconductor Device Simulation
… convergence analysis of Gummel's method and quasi-Newton methods is extended to a nonuniform mesh and the Bernoulli function discretization. It is proved that Gummel's method and the quasi-Newton methods for the scaled carrier densities and carrier densities converge locally for sufficiently …
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Least Relative Change Quasi-Newton Updates for Chemical Engineering Process Optimization
… using traditional sparse least absolute change quasi-Newton updates.
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Analytical study of the Least Squares Quasi-Newton method for interaction problems
… and show that it can be interpreted as a block quasi-Newton method with approximate Jacobians based on a least squares formulation. We also establish and investigate other algorithms that exploit the original idea but use a single approximate Jacobian. The main focus in this thesis lies on …
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On the Use of Quasi-Newton Methods for the Minimization of Convex Quadratic Splines
<p>In reformulating a strictly convex quadratic program with simple bound constraints as the unconstrained minimization of a strictly convex quadratic spline, established algorithms can be implemented with relaxed differentiability conditions. In this work, the positive definite secant update …
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A quasi-Newton algorithm for solving the power flow problem in inverter-based power systems
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-10-19 without embargo terms
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Location of stable and unstable equilibrium configurations using a model trust region quasi-Newton method and tunnelling
A hybrid method consists of a quasi-Newton method and a homotopy method for locating multiple equilibrium configurations has been proposed recently. The hybrid method combined the efficiency of a quasi-Newton method capable of locating stable and unstable equilibrium solutions with a robust …
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A modified augmented Lagrangian merit function, and Q-superlinear characterization results for primal-dual Quasi-Newton interior-point method for nonlinear programming
… The first class corresponds to a path-following Newton method formulated in terms of the nonnegative variables rather than all primal and dual variables. The centrality condition is a relaxation of the perturbed Karush-Kuhn-Tucker condition and primarily forces feasibility in the constraints. In …
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The updated subspaces method in optimization and in solving linear systems of equations
… Updated Conjugate Subspaces method, an modified quasi-Newton method for solving nonlinear unconstrained minimization problems, has flexibility of choosing different quadratic approximation at each iteration and therefore has potential of improving the rate of convergence given by the quasi-Newton …
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Geometry of Feedback Control and Learning
… gradient flow, natural gradient flow and the quasi-Newton flow. The coercive property suggests that these flows admit unique solutions while gradient dominated property indicates that the corresponding Lyapunov functionals decay at an exponential rate; quadratic growth on the other hand …
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Solving The Prandtl Boundary Layer Equation in Fluid Dynamics Via Non-Linear Numerical Optimization
… of O(h4) or O(h6).A powerful variation of the Quasi-Newton methods known as the BFGS Quasi-Newton iteration is applied with a quadratic convergence rate [41][43] while the conventional FVM converges linearly using the SIMPLE iteration approach. In this work, an Objective Function (or Penalty …
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Fast Algorithms for Volterra-Series-Based Nonlinear Adaptive Filters
… filter the two algorithms essentially implement quasi-Newton algorithm with $O\lbrack {\rm N}\sp2\rbrack$ computational complexity which is equivalent to O (N) computational complexity of fast algorithms for linear adaptive filters. A new structure based on linear transformation and power …
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O método de direções viáveis em duas estapas para programação não-linear e aplicações a programação quadrática
… rates are presented. Versions which use quasi-Newton techniques have superlinear convergence rate.
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Towards Real-Time Simulation Of Hyperelastic Materials
… of these types of materials currently relies on Newton's method, which is slow, even with only one iteration per timestep. In this work, we start from simple material models such as mass-spring systems or as-rigid-as-possible materials. We express the widely used implicit Euler time integration …
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Centrifugal compressor return channel shape optimization using adjoint method
… finite-difference calculations and embedded in a quasi- Newton optimization algorithm. An optimal design was proposed, which achieved an approximately 5% performance improvement compared to the baseline design in an incompressible laminar flow. The geometry was assessed in a compressible turbulent …
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Calibração automática de modelos tipo chuva-vazão utilizando técnicas de suavização: uma aplicação ao modelo SMAP-II
… This work examines the possibility of using Quasi-Newton type (second derivative-based) optimization algorithm for calibration of conceptual Rainfall-Runoff models. The technique developed presents a previous structural modification of a typical model to obtain the objective function explicit …
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Fréchet Sensitivity Analysis and Parameter Estimation in Groundwater Flow Models
… with algorithms based on adjoint equations, quasi-Newton schemes, and multilevel optimization. In addition to the parameter estimation problem, we consider properties of the parameter to solution map. This includes invertibility (known as identifiability) and differentiability properties of …
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Energy management for a multiple-pulse missile
… problem which is solved using a second-order, quasi-Newton method with constraint projection. The two solutions are found to compare well. This result allows confidence in the use of the nonlinear-programming technique to solve optimization problems in flight mechanics for which no analytical …
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