An Adjoint Variable Method for Wideband Second-Order Sensitivity Analysis Through FDTD
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Bibliographic record
Abstract
We propose an efficient adjoint variable method (AVM) for estimating wideband second-order response sensitivities using the finite-difference time-domain (FDTD) approach. Our AVM approach reduces the number of required simulations for computing the Hessian matrix of the desired objective function from O(n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) to only n + 1 where n is the number of designable parameters. All first-order sensitivities are also estimated as a by-product. Our sensitivity technique is illustrated through 1-D, 2-D, and 3-D electromagnetic examples involving both dispersive and nondispersive materials. The accuracy of our AVM approach is verified through comparison with analytical sensitivity results or sensitivities estimated using the accurate but computationally intensive central finite-difference (CFD) approximations.
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Full frame distilled prediction
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Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
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Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
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