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"Reverse-Schur" Approach to Optimization with Linear PDE Constraints: Application to Biomolecule Analysis and Design

Jaydeep P. Bardhan, Michael D. Altman, B. Tidor, Jacob K. White
2009 Journal of Chemical Theory and Computation  
The theoretical basis for electrostatic optimization derives from linear-response theory, most commonly continuum models, and simple assumptions about molecular binding processes.  ...  The co-optimization algorithm achieves improved performance by solving the optimization and electrostatic simulation problems simultaneously, and is applicable to both unconstrained and constrained optimization  ...  For comparison, the explicit-Hessian boundary-element approach leads to an unconstrained optimum with −0.33 e net charge, and the finite-difference optimal charges sum to 0.06 e; the preponderance of the  ... 
doi:10.1021/ct9001174 pmid:23055839 pmcid:PMC3465730 fatcat:cschrbj45bbyfaetp5innshcci

Optimal Aeroacoustic Shape Design Using the Surrogate Management Framework

Alison L. Marsden, Meng Wang, John E. Dennis, Jr., Parviz Moin
2004 Optimization and Engineering  
Optimal shapes that minimize noise have been identified for the trailing-edge problem in constrained and unconstrained cases.  ...  The use of a polling step in the SMF guarantees that the algorithm generates a convergent subsequence of mesh points, each iterate of which is a local minimizer of the cost function on a mesh in the parameter  ...  The authors wish to thank the IMA for providing a forum for collaboration, as well as Charles Audet and Petros Koumoutsakos for valuable discussions.  ... 
doi:10.1023/b:opte.0000033376.89159.65 fatcat:upqbjnrkrzep5hdghh5vo65wi4

Constrained and Unconstrained Optimization Formulations for Structural Elements in Unilateral Contact with an Elastic Foundation

Ricardo A. M. Silveira, Wellington L. A. Pereira, Paulo B. Gonçalves
2008 Mathematical Problems in Engineering  
In the first approach, the finite element method is used to discretize the structure and elastic foundation and the contact problem is formulated as a constrained optimization problem.  ...  In this work, two numerical methodologies are proposed for the solution of unilateral contact problems between a structural member (beam or arch) and an elastic foundation.  ...  Special thanks are also due to Professor Michael Engelhardt and his department at the University of Texas for their hospitality during the manuscript's preparation.  ... 
doi:10.1155/2008/786520 fatcat:iazzr6qb7zesdjgvtbpg3gxg4q

Equation-free, coarse-grained computational optimization using timesteppers

Aditya Bindal, Marianthi G. Ierapetritou, Suhrid Balakrishnan, Antonios Armaou, Alexei G. Makeev, Ioannis G. Kevrekidis
2006 Chemical Engineering Science  
The efficiency of alternative optimization formulations is compared; we see that it can be enhanced by exploiting a separation of time-scales in the system dynamics.  ...  The approach substitutes the evaluation of closed form macroscopic equations with the design and execution of appropriately initialized short bursts of fine scale simulation; processing the simulation  ...  Acknowledgements Financial support from the Air Force Office of Scientific Research (Dynamics and Control), National Science Foundation, ITR, NSF/CTS 0456657 and Office of Naval Research Contract no. 0014  ... 
doi:10.1016/j.ces.2005.06.034 fatcat:vlix22fkmzgh3cludyd7dcixva

Adaptive efficient global optimization of systems with independent components

Samee Ur Rehman, Matthijs Langelaar
2017 Structural And Multidisciplinary Optimization  
We present a novel approach for efficient optimization of systems consisting of expensive to simulate components and relatively inexpensive system-level simulations.  ...  The metamodels are adaptively sampled based on a system level infill sampling criterion using Efficient Global Optimization.  ...  Similarly, the effectiveness of the technique was compared with building a response surface of the system via LHS and globally optimizing the cheap response.  ... 
doi:10.1007/s00158-017-1663-y fatcat:en6hatpydbgcffylnvjsagx4f4

Structural Optimization with Thermal and Mechanical Constraints

Suqiang Xu, Ramana V. Grandhi
1999 Journal of Aircraft  
This coupling in- cludes both temperature and its derivative effects on structural responses and its derivatives. 3) Approximation of the internal forces instead of stresses: The stress constraints are  ...  Haftka and Markus'° explored two avenues to enhance the effectiveness of the finite difference approach to calculating derivatives of temperatures and thermal con- straints.  ... 
doi:10.2514/2.2442 fatcat:rh4ghutcdnaihblxmashylfs2u

CHOMP: Covariant Hamiltonian optimization for motion planning

Matt Zucker, Nathan Ratliff, Anca D. Dragan, Mihail Pivtoraiko, Matthew Klingensmith, Christopher M. Dellin, J. Andrew Bagnell, Siddhartha S. Srinivasa
2013 The international journal of robotics research  
In this paper, we present CHOMP (covariant Hamiltonian optimization for motion planning), a method for trajectory optimization invariant to reparametrization.  ...  CHOMP uses functional gradient techniques to iteratively improve the quality of an initial trajectory, optimizing a functional that trades off between a smoothness and an obstacle avoidance component.  ...  Acknowledgments We thank Gil Jones and Willow Garage for their support, particularly in performing ROS experiments.  ... 
doi:10.1177/0278364913488805 fatcat:lelp5mb6xrbwpli6npvpotli74

Aerodynamic Shape Optimization [chapter]

2015 Simulation-Driven Aerodynamic Design Using Variable-Fidelity Models  
This paper presents a historical perspective on the development and application of aerodynamic shape optimization (ASO) methods for supersonic aircraft design.  ...  The paper closes with a discussion on future research activities and possible pathways to the creation of the next supersonic commercial transport.  ...  10 Comparison between baseline and optimized Premier I business jet representations: note the reduction in wing upper surface shock strength and a general reduction in high Mach number (low pressure)  ... 
doi:10.1142/9781783266296_0002 fatcat:y545vhdwevcexbj6gvy6vbubai


2002 International Journal of Uncertainty Fuzziness and Knowledge-Based Systems  
The sum normal constraint is applied in t his paper to both gradient descent optimization and Kalman filter optimization of fuzzy membership fu nctions.  ...  H we constrain the membership functions to a certain shape (e.g., t riangles or trapezoids) then each membership function can be parameteri'l:ed by a small number of variables and the membership optimization  ...  Acknowledgements The comments of the referees were significant in correcting mistakes and strength ening this paper from its original form.  ... 
doi:10.1142/s0218488502001533 fatcat:zrgle47en5glta6ihifk4ep5sa

Efficiency optimization and symmetry-breaking in a model of ciliary locomotion

Sébastien Michelin, Eric Lauga
2010 Physics of Fluids  
Using additional constrained optimizations, as well as a constructed analytical ansatz, we derive a complete optimization diagram where all swimming efficiencies, swimming speeds, and amplitude of surface  ...  This wave motion is analyzed using a formal modal decomposition, is found to occur in the same direction as the swimming direction, and is interpreted as due to a spatial distribution of phase-differences  ...  ACKNOWLEDGMENTS We thank Sunghwan ͑Sunny͒ Jung for the use of his images in Fig. 1 . Funding by the National Science Foundation ͑Grant No. CBET-0746285 to E.L.͒ is gratefully acknowledged.  ... 
doi:10.1063/1.3507951 fatcat:7ydmrdu7v5dr3gltiuvpptbrs4

Page 2943 of Mathematical Reviews Vol. , Issue 89E [page]

1989 Mathematical Reviews  
Shyamal Chatterjee (6-CALC-AM) 89e:90188 90C30 65K05 Ringuest, Jeffrey L. (1-BSTC) Substitute derivatives in unconstrained optimization: a comparison of finite difference and response surface approximations  ...  Summary: “This paper compares the accuracy of unconstrained gradient search using substitute derivatives approximated by finite differences or first-order response surfaces.  ... 

Reduced-Order Models for Integrated Aeroservoelastic Optimization

Moti Karpel
1999 Journal of Aircraft  
{y} (25) The substitution of Eq. (25) into Eq. (24) yields the closed- loop equation of motion [Z]{£} = [A}{x} + {B,}w (26) where only the control related row of [A] is different than that of [A] in Eq  ...  The differences be- tween the various approximation methods can be expressed in terms of the approximation formula, constraints, and dat weighting.  ... 
doi:10.2514/2.2420 fatcat:22ae43pz6jgvbgh6y3lr5pobx4

Post-buckling optimization of composite structures using Koiter's method

Søren R. Henrichsen, Paul M. Weaver, Esben Lindgaard, Erik Lund
2016 International Journal for Numerical Methods in Engineering  
In asymptotic methods the non-linear problem is substituted by a series of simpler problems, which are fast and easy to solve [11] .  ...  Regardless, this parametrization is used as the laminate parametrization is not the focus of this work, and the equations are derived in a general sense, thus they can be used with different parametrizations  ...  ACKNOWLEDGEMENTS The first author would like to thank Simon White, University of Bristol, for fruitful discussions on Koiter's asymptotic method.  ... 
doi:10.1002/nme.5239 fatcat:kgjdn7ndnjehbd4iktjhjro7si

Multi-Conceptual Mechanical Design Optimization of Capacitive Pressure Sensors via Finite Element Analysis with use of Anisotropic Behavior of Silicon <111> Crystal: Summary of Design Optimization Approaches

Amir Javidinejad
2019 Journal of Applied Mechanical Engineering  
The approximate closed-form deflection solutions are developed using the anisotropic thin plate theory and the diaphragm deflection behaviour of the FEM optimized design is compared with this thin plate  ...  In this research work, a micro-pressure diaphragm which possess linear pressure-deflection behaviour is designed via FEM optimization techniques.  ...  Therefore, a need for finite element analysis optimization is established here.  ... 
doi:10.35248/2168-9873.19.8.317 fatcat:opllzgkdxfhlvb3my4swwrrcbm

Simulation and optimization of pressure-swing adsorption systems for air separation

Ling Jiang, Lorenz T. Biegler, V. Grant Fox
2003 AIChE Journal  
After a start-up time, the system reaches cyclic steady state (CSS), at which the conditions in each bed at the start and end of each cycle are identical.  ...  In addition, we modify a standard flux limiter in order to deal with non-differentiable terms and ensure computational accuracy and efficiency.  ...  Acknowledgements The authors grateful acknowledge the financial support of the NSF/GOALI program and Air Products and Chemicals Inc. The authors would also like to thank Drs.  ... 
doi:10.1002/aic.690490508 fatcat:zospiealubafnjs7ia2lqtuvfm
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