# Derivative-free optimization of a rapid-cycling synchrotron

@article{Eldred2022DerivativefreeOO, title={Derivative-free optimization of a rapid-cycling synchrotron}, author={Jeffrey Eldred and Jeffrey Larson and Misha Padidar and Eric C. Stern and Stefan M. Wild}, journal={Optimization and Engineering}, year={2022} }

We develop and solve a constrained optimization model to identify an integrable optics rapid-cycling synchrotron lattice design that performs well in several capacities. Our model encodes the design criteria into 78 linear and nonlinear constraints, as well as a single nonsmooth objective, where the objective and some constraints are deﬁned from the output of Synergia, an accelerator simulator. We detail the diﬃculties of the 23-dimensional simulation-constrained decision space and establish…

## 4 Citations

### Structure-Aware Methods for Expensive Derivative-Free Nonsmooth Composite Optimization

- Computer Science, Mathematics
- 2022

New methods for solving a broad class of bound-constrained nonsmooth composite minimization problems and accompanying implementations of these methods are provided, including a novel manifold sampling algorithm with subproblems that are in a sense primal versions of the dual problems solved by previous manifold sampling methods.

### Constrained blackbox optimization with the NOMAD solver on the COCO constrained test suite

- Computer ScienceGECCO Companion
- 2022

The mesh adaptive direct search (MADS) derivative-free optimization algorithm using the progressive barrier strategy to handle quantifiable and relaxable constraints is described and tested on the new bbob-constrained suite of analytical constrained problems from the COCO platform, and compared with the CMA-ES heuristic.

### Modeling approaches for addressing unrelaxable bound constraints with unconstrained optimization methods

- PsychologyOptimization Letters
- 2022

### Modeling Approaches for Addressing Simple Unrelaxable Constraints with Unconstrained Optimization Methods

- Computer Science
- 2022

An algorithm is developed that exploits the structure of the sigmoidal warping to guarantee that unconstrained optimization algorithms applied to the merit function will be a stationary point to the desired tolerance.

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