A Parallel Multiobjective Efficient Global Optimization: The Finite Element Method in Optimal Design and Model Development (original) (raw)

A Single- and Multi-objective Optimization Algorithm for Electromagnetic Devices Assisted by Adaptive Kriging Based on Parallel Infilling Strategy

Journal of Electrical Engineering & Technology, 2020

A computationally efficient surrogate model is suggested to approximate the objective and constraint function values, which replace expensive evaluation of the objective and constraint function values in numerical simulation-based optimization. Kriging surrogate model has been widely used in surrogate-based design optimization (SBDO) to replace the highly nonlinear black-box functions. In this paper, a novel adaptive Kriging model based on parallel infilling strategy is proposed to improve both the numerical accuracy and efficiency of the SBDO methods. The parallel infilling strategy consists of two parts: local sampling and globaluthor sampling. In the local sampling, new additional sampling points are generated only within a limited region that is determined according to the optimal point at the last iteration, while in global sampling they are generated based on the fitting error estimation in the whole region. The effectiveness of the proposed algorithm is verified through applications to analytical functions. Then the algorithm is applied to the multi-objective optimal design of an ironless permanent magnet synchronous linear motor.

A hybrid one‐then‐two stage algorithm for computationally expensive electromagnetic design optimization

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, 2007

PurposeThe purpose of this paper is to propose a surrogate model‐assisted optimization algorithm which effectively searches for the optimum at the earliest opportunity, avoiding the need for a large initial experimental design, which may be wasteful.Design/methodology/approachThe methodologies of two‐stage and one‐stage selection of points are combined for the first time. After creating a small experimental design, a one‐stage Kriging algorithm is used to search for the optimum for a fixed number of iterations. If it fails to locate the optimum, the points it samples are then used in lieu of a traditional experimental design to initialize a two‐stage algorithm.FindingsThe proposed approach was tested on a mathematical test function. It was found that the optimum could be located, without necessarily constructing an accurate surrogate model first. The algorithm performed well on an electromagnetic design problem, outperforming both a random search and a genetic algorithm, in signific...

A Parallel Surrogate Model Assisted Evolutionary Algorithm for Electromagnetic Design Optimization

IEEE Transactions on Emerging Topics in Computational Intelligence, 2019

Optimization efficiency is a major challenge for electromagnetic (EM) device, circuit and machine design. Although both surrogate model-assisted evolutionary algorithms (SAEAs) and parallel computing are playing important roles in addressing this challenge, there is little research that investigates their integration to benefit from both techniques. In this paper, a new method, called parallel SAEA for electromagnetic design (PSAED), is proposed. A state-of-the-art SAEA framework, surrogate model-aware evolutionary search, is used as the foundation of PSAED. Considering the landscape characteristics of EM design problems, three differential evolution mutation operators are selected and organized in a particular way. A new SAEA framework is then proposed to make use of the selected mutation operators in a parallel computing environment. PSAED is tested by a micromirror and a dielectric resonator antenna as well as four mathematical benchmark problems of various complexity. Comparisons with state-of-the-art methods verify the advantages of PSAED in terms of efficiency and optimization capacity.

Exploration versus exploitation using kriging surrogate modelling in electromagnetic design

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, 2012

PurposeDesign optimisation of electromagnetic devices is computationally expensive as use of finite element or similar codes is normally required. Thus, one of the objectives is to have efficient algorithms minimising the number of necessary function calls. In such algorithms a balance between exploration and exploitation needs to be found not to miss the global optimum but at the same time to make efficient use of information already found. The purpose of this paper is a contribute to the search of such efficient algorithms.Design/methodology/approachThis paper discusses the use of kriging surrogate modelling in multiobjective design optimisation in electromagnetics. The investigation relies on the use of special test functions.FindingsThe importance of achieving appropriate balance between exploration and exploitation is emphasised when searching for the global optimum. New strategies are proposed using kriging.Originality/valueIt is argued that the proposed approach will yield a ...

An environment for the optimization of electromagnetic design

IEEE Transactions on Magnetics, 2000

In this paper a short description of the EPOCH design optimization environment will be given and results on the parallelization of the electromagnetic analysis codes based on the Bulk Synchronous Parallel approach, as well as testing of the environment using industrially relevant 2d and 3d test cases, such as the design of a microwave oven, eddy current brake, advanced accelerator magnet and thin film recording head, will be presented.

Optimization of electromagnetic devices using parameterized templates

IEEE Transactions on Magnetics, 2001

The extraction of sensitivity information from a clustered neuro-fuzzy model is addressed in this paper. Subsequently, this permits the application of deterministic methods on the approximated objective function, significantly improving the optimization process. Results from an analytical and a practical electromagnetic problem, which show the applicability of the formulation, are presented.

Screening applied to the numerical modeling of electromagnetic devices

Ain Shams Engineering Journal, 2010

Electromagnetic modeling and optimization problems usually involve a large number of varying parameters. A designer may use different kinds of models during the design optimization process. Some models, e.g. finite-element model (FEM), can be very precise, but require long computation time, thus limiting the number of design parameters. Therefore, the designer ought to use a screening process to reduce the number of parameters. This is achieved using the design of experiments (DOE) approach. Hence, combining FEM and DOE is a practical way to be used in electromagnetic prototyping where the FEM is used for an efficient virtual prototyping and the DOE approach is used to investigate the effect of all possible parameters of a given device. This paper presents the application of DOE as a preliminary step for the electromagnetic modeling and optimization process. To illustrate this technique we apply it to workshop TEAM 25 problem.

Multiobjective Optimization in Computational Electromagnetics

In this paper we show how multiobjective optimization can be applied to elec- tromagnetic problems. The optimization algorithms are combined with CAD and mesh generation software, and electromagnetic solvers. Three dieren t multiobjective optimization methods are applied: one evolutionary method, one method based on scalarizing of the objectives combined with a method for single objective optimization and a multiobjective respond surface method. To demonstrate the procedure we study the optimization of the return loss of a patch antennas at two dieren t frequencies.

A hybrid multiobjective differential evolution method for electromagnetic device optimization

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, 2011

Purpose -The purpose of this paper is to show that the performance of differential evolution (DE) can be substantially improved by a combination of techniques. These enhancements are applicable to both single and multiobjective problems. Their combined use allows the optimization of complex 3D electromagnetic devices. Design/methodology/approach -DE is improved by a combination of techniques which are applied in a cascade way and their single and combined effect is tested on well-known benchmarks and domain-specific applications. Findings -It is shown that the combined use of enhancement techniques provides substantial improvements in the speed of convergence for both single and multiobjective problems.

Robust design optimisation of electromagnetic devices exploiting gradient indices and Kriging

IET Science, Measurement & Technology, 2014

Since uncertainties in variables are unavoidable, an optimal solution must consider the robustness of the design. The gradient index approach provides a convenient way to evaluate the robustness but is inconclusive when several possible solutions exist. To overcome this limitation, a novel methodology based on the use of firstand second-order gradient indices is proposed introducing the notion of gradient sensitivity. The sensitivity affords a measure of the change in the objective function with respect to the uncertainty of the variables. A Kriging method assisted by algorithms exploiting the concept of rewards is employed to facilitate function predictions for the robust optimisation process. The performance of the proposed algorithm is assessed through a series of numerical experiments. A modification to the correlation model through the introduction of a Kriging predictor and mean square error criterion allows efficient solution of large scale and multi-parameter problems. The three-parameter version of TEAM Workshop Problem 22 has been used for illustration.