Results 71 to 80 of about 77,620 (219)
Using wavelets for time series forecasting: Does it pay off? [PDF]
By means of wavelet transform a time series can be decomposed into a time dependent sum of frequency components. As a result we are able to capture seasonalities with time-varying period and intensity, which nourishes the belief that incorporating the ...
Schlüter, Stephan, Deuschle, Carola
core
Sparse orthogonal matrices and the Haar wavelet
Discrete Applied Mathematics, 2000 The authors discuss the sparsity of orthogonal matrices which have a column of nonzero entries. It is shown that the minimun number of nonzero entries in such a matrix of size \(m\times m\) is \[ (\lfloor m\rfloor +3)m-2^{\lfloor m\rfloor+1}. \] This is optimal, as the paper characterizes the matrices which achieve this number.
Gi-Sang Cheon, Bryan L. Shader
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Journal of Agrarian Change, EarlyView.ABSTRACT This paper explores the paradox of seeking local solutions in rural development when conflicts result from structural transformations of the agrarian economy driven by national political choices. Since the 1990s, participatory approaches inspired by neo‐institutionalist theories of local governance have encouraged development actors to view ...
Toni‐Giovanni Pegurri
wiley +1 more source
Wavelet Multiresolution Analysis of High-Frequency FX Rates, Summer 1997 [PDF]
FX pricing processes are nonstationary and their frequency characteristics are time-dependent. Most do not conform to geometric Brownian motion, since they exhibit a scaling law with a Hurst exponent between zero and 0.5 and fractal dimensions between 1 ...
Jeyanthi Karuppiah, Cornelis A. Los
core
Further evidence for near-Tsirelson Bell–CHSH violations in quantum field theory via Haar wavelets
European Physical Journal C: Particles and FieldsThis paper investigates a recent construction using bumpified Haar wavelets to demonstrate explicit violations of the Bell–Clauser–Horne–Shimony–Holt inequality within the vacuum state in Quantum Field Theory.
David Dudal, Ken Vandermeersch
doaj +1 more source
Wavelets obtained by continuous deformations of the Haar wavelet
Revista Matemática Iberoamericana, 1996 One might obtain the impression, from the wavelet literature, that the class of orthogonal wavelets is divided into subclasses, like compactly supported ones on one side, band-limited ones on the other side. The main purpose of this work is to show that, in fact, the class of low-pass filters associated with "reasonable" (in the localization sense, not
Bonami, Aline +2 more
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Hilbert Transform Pairs of Wavelets
Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 4, December 2026.ABSTRACT The orthogonal projection of a real orthonormal wavelet basis onto the Hardy space—consisting of functions whose Fourier transform is supported only on the positive real axis—yields a Parseval frame of wavelets. Motivated by practical considerations, Kingsbury proposed the use of two real scaling functions from multiresolution analyses (MRAs ...
Moritz Proell
wiley +1 more source
Approximating of functions from holder classes Hα [0, 1] by haar wavelets [PDF]
, 2017 In the present work, a new direct computational method for solving definite integrals based on Haar wavelets is introduced. The definite integral of the functions from Holder classes is replaced with the approximation of the function by Haar wavelets and
Ahatjonovich, Anvarjon Ahmedov +3 more
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IEEE AccessThis paper evaluates the performance of six different machine learning (ML) algorithms for classifying power quality disturbances (PQDs), with statistical features extracted using discrete wavelet transform (DWT) as feature input.
Uvesh Sipai +5 more
doaj +1 more source
Magnetic Resonance in Medicine, Volume 96, Issue 5, Page 2489-2504, November 2026.ABSTRACT Purpose To improve the accuracy of diffusion‐weighted powder average signals for diffusion encoding with arbitrary b‐tensors. Methods We identify an intrinsic dihedral (D2) symmetry of diffusion signals for arbitrary diffusion encoding, which defines their natural signal space (a quotient of 3D rotations). Based on this, we propose a method to
Sune Nørhøj Jespersen +1 more
wiley +1 more source