Results 121 to 130 of about 4,977,477 (349)
A characterization of Hilbert space [PDF]
Proceedings of the American Mathematical Society, 1974 A real Banach space E of dimension _3 is an inner product space iff there exists a bounded smooth convex subset of E which is the range of a nonexpansive retraction. De Figueiredo and Karlovitz [3] have shown that if E is a strictly convex real finite-dimensional Banach space and dim E> 3 then there can exist no bounded smooth nonexpansive retract of E
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Bolt Anchorage Quality Levels Classification Method Based on HO‐VMD‐CNN‐BiLSTM
Energy Science &Engineering, EarlyView.First, the original ultrasound‐guided wave signal data is decomposed into multiple sub‐signals with varying frequencies using VMD to capture the multi‐scale features within the data. Second, the decomposed and noise‐reduced signal, processed by the HO‐VMD algorithm, is input into the CNN for further feature extraction through convolution and pooling ...
Fan Kesong +7 more
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Energy Science &Engineering, EarlyView.A support vector machine (SVM) algorithm was applied to quantitatively predict the connectivity of the sand bodies. Verification using dynamic and static data demonstrated that the prediction accuracy of the algorithm reached 88%. The quantitative sand body connectivity results were used to establish a single sand body model.
Hui He +6 more
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On bidual bases in the space of symmetric analytic functions on $ell_{1}$
Karpatsʹkì Matematičnì Publìkacìï, 2013 We consider a special Hilbert space of symmetric analytic functions on$ell_1$ and construct a pair of bidual bases of polynomials.}{Hilbert space, symmetricanalytic functions, bidual ...
O. M. Holubchak, A. V. Zagorodnyuk
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Stock Return Prediction Based on a Functional Capital Asset Pricing Model
Journal of Forecasting, EarlyView.ABSTRACT The capital asset pricing model (CAPM) is readily used to capture a linear relationship between the daily returns of an asset and a market index. We extend this model to an intraday high‐frequency setting by proposing a functional CAPM estimation approach.
Ufuk Beyaztas +3 more
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On the definition of Hilbert space
Manuscripta Mathematica, 1977 The projection theorem expresses a central feature of classical Hilbert space. Do other infinite dimensional sesquilinear spaces share this property? We show here that this is not the case for several prominent candidates; in particular Kalish's p-adic Hilbert spaces, Springers non archimedean normed spaces, the positive definite spaces over ordered ...
Gross, Herbert, Keller, Hans A.
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Laser &Photonics Reviews, EarlyView.Fully exploiting the broad untapped terahertz spectrum necessitates extending the bandwidth of practical guided‐wave systems. This work introduces a substrateless quasi‐optical integration platform to meet this need. Classical optical principles going back to the time of Michelson are adapted to a planar, micro‐machined, monolithic‐silicon platform ...
Daniel Headland +4 more
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On Fuzzy Co-Pre-Hilbert Spaces
Journal of Kufa for Mathematics and Computer, 2013 This paper introduces the concepts fuzzy pre-Hilbert spaces and fuzzy co-pre-Hilbert spaces and proves some theorems in this subject.Â
Noori F. Al-Mayahi, Intisar H. Radhi
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Laser &Photonics Reviews, EarlyView.A mid‐infrared frequency‐swept source operating is presented at 50 MScans s−1 using frequency down‐conversion of time‐stretched 1.5‐µm pulses generated from an Er‐doped mode‐locked fiber laser. The developed source enables high‐resolution gas‐phase MIR spectroscopy with a bandwidth of 15 cm−1 and a resolution of 0.086 cm−1 at a measurement rate of 50 ...
Makoto Shoshin +4 more
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More on doubled Hilbert space in double-scaled SYK
Physics Letters BWe continue our study of the doubled Hilbert space formalism of double-scaled SYK model initiated in Okuyama (2024) [7]. We show that the 1-particle Hilbert space introduced by Lin and Stanford (2023) [6] is related to the doubled Hilbert space H0⊗H0 of ...
Kazumi Okuyama
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