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111.
We report experimental observation of Bardasis–Schrieffer-type s-symmetry collective mode in the d-wave high Tc superconductors. The mode persists above Tc in the pseudogap phase of the underdoped superconductors — direct spectroscopic evidence of the correlations in the particle–particle channel above Tc. 相似文献
112.
Jameel Ahmed Bhutto Lianfang Tian Qiliang Du Zhengzheng Sun Lubin Yu Muhammad Faizan Tahir 《Entropy (Basel, Switzerland)》2022,24(3)
Medical image fusion (MIF) has received painstaking attention due to its diverse medical applications in response to accurately diagnosing clinical images. Numerous MIF methods have been proposed to date, but the fused image suffers from poor contrast, non-uniform illumination, noise presence, and improper fusion strategies, resulting in an inadequate sparse representation of significant features. This paper proposes the morphological preprocessing method to address the non-uniform illumination and noise by the bottom-hat–top-hat strategy. Then, grey-principal component analysis (grey-PCA) is used to transform RGB images into gray images that can preserve detailed features. After that, the local shift-invariant shearlet transform (LSIST) method decomposes the images into the low-pass (LP) and high-pass (HP) sub-bands, efficiently restoring all significant characteristics in various scales and directions. The HP sub-bands are fed to two branches of the Siamese convolutional neural network (CNN) by process of feature detection, initial segmentation, and consistency verification to effectively capture smooth edges, and textures. While the LP sub-bands are fused by employing local energy fusion using the averaging and selection mode to restore the energy information. The proposed method is validated by subjective and objective quality assessments. The subjective evaluation is conducted by a user case study in which twelve field specialists verified the superiority of the proposed method based on precise details, image contrast, noise in the fused image, and no loss of information. The supremacy of the proposed method is further justified by obtaining 0.6836 to 0.8794, 0.5234 to 0.6710, and 3.8501 to 8.7937 gain for , CRR, and AG and noise reduction from 0.3397 to 0.1209 over other methods for objective parameters. 相似文献
113.
George W. Gokel Harold M. Gerdes David E. Miles John M. Hufnal Glenn A. Zerby 《Tetrahedron letters》1979,20(36):3375-3378
The title heterocycle is used as a carbonyl anion equivalent in the preparation of aldehydes and α-silyl ketones; the key step is the thermal demasking of the heterocycle by loss of isobutylene and sulfur dioxide. 相似文献
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Stability and convergence of finite difference schemes approximating an elliptic partial differential equation with interface are examined. A convergence rate estimate compatible with the smoothness of the input data is obtained. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
118.
Stability and convergence of finite difference schemes approximating a general parabolic partial differential equation with interface are examined. Convergence rate estimates compatible with the smoothness of the input data are obtained. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
119.
We show that algebraic dynamical systems with entropy rank one have uniformly exponentially many periodic points in all directions.
120.
Miglena Koleva Lubin Vulkov 《Numerical Methods for Partial Differential Equations》2007,23(2):379-399
The numerical solution of the heat equation in unbounded domains (for a 1D problem‐semi‐infinite line and for a 2D one semi‐infinite strip) is considered. The artificial boundaries are introduced and the exact artificial boundary conditions are derived. The original problems are transformed into problems on finite domains. The space semi‐discretization by finite element method and the full approximation by the implicit‐explicit Euler's method are presented. The solvability of the full discretization schemes is analyzed. Computational examples demonstrate the accuracy and the efficiency of the algorithms. Also, the behavior of blowing up solutions is examined numerically. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 23: 379–399, 2007 相似文献