Results 11 to 20 of about 635,086 (230)
Nonlinear Approximations in Cryptanalysis Revisited
IACR Transactions on Symmetric Cryptology, 2018 This work studies deterministic and non-deterministic nonlinear approximations for cryptanalysis of block ciphers and cryptographic permutations and embeds it into the well-understood framework of linear cryptanalysis.
Christof Beierle +2 more
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Weighted Thresholding and Nonlinear Approximation
, 2017 We present a new method for performing nonlinear approximation with redundant dictionaries. The method constructs an $m-$term approximation of the signal by thresholding with respect to a weighted version of its canonical expansion coefficients, thereby ...
Nielsen, Morten, Ottosen, Emil Solsbæk
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On nonlinear uniform approximation
Journal of Approximation Theory, 1977 M.J Gillotte, H.W McLaughlin
openalex +3 more sources
Journal of Mathematical Analysis and Applications, 1972 Richard B. Barrar, H. L. Loeb
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Nonlinear approximation with nonstationary Gabor frames [PDF]
Advances in Computational Mathematics, 2017 We consider sparseness properties of adaptive time-frequency representations obtained using nonstationary Gabor frames (NSGFs). NSGFs generalize classical Gabor frames by allowing for adaptivity in either time or frequency.
Nielsen, Morten, Ottosen, Emil Solsbæk
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On the Approximation of Moments for Nonlinear Systems [PDF]
IEEE Transactions on Automatic Control, 2021 Model reduction by moment-matching relies upon the availability of the so-called moment . If the system is nonlinear, the computation of moments depends on an underlying specific invariance equation, which can be difficult or impossible to solve. This article presents four technical contributions related to the theory of moment matching: first, we ...
Nicolas Faedo +3 more
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Optimal Stable Nonlinear Approximation [PDF]
Foundations of Computational Mathematics, 2021 While it is well known that nonlinear methods of approximation can often perform dramatically better than linear methods, there are still questions on how to measure the optimal performance possible for such methods. This paper studies nonlinear methods of approximation that are compatible with numerical implementation in that they are required to be ...
Cohen, Albert +3 more
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A nonlinear quantum adiabatic approximation [PDF]
Nonlinearity, 2020 This paper is devoted to a generalisation of the quantum adiabatic theorem to a nonlinear setting. We consider a Hamiltonian operator which depends on the time variable and on a finite number of parameters and acts on a separable Hilbert space of which we select a fixed basis. We study an evolution equation in which this Hamiltonian acts on the unknown
Fermanian Kammerer, Clotilde +1 more
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Nonlinear approximation via compositions [PDF]
Neural Networks, 2019 Given a function dictionary $\cal D$ and an approximation budget $N\in\mathbb{N}^+$, nonlinear approximation seeks the linear combination of the best $N$ terms $\{T_n\}_{1\le n\le N}\subseteq{\cal D}$ to approximate a given function $f$ with the minimum approximation error\[\varepsilon_{L,f}:=\min_{\{g_n\}\subseteq{\mathbb{R}},\{T_n\}\subseteq{\cal D}}\
Zuowei Shen, Haizhao Yang, Shijun Zhang
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Nonlinear Approximation with Redundant Dictionaries [PDF]
Proceedings. (ICASSP '05). IEEE International Conference on Acoustics, Speech, and Signal Processing, 2005., 2006 In this paper we study nonlinear approximation and data representation with redundant function dictionaries. In particular, approximation with redundant wavelet bi-frame systems is studied in detail. Several results for orthonormal wavelets are generalized to the redundant case. In general, for a wavelet bi-frame system the approximation properties are
Borup, Lasse +2 more
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