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Weighted Approximation by Left Quasi-interpolants of Derivatives of Gamma Operators
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作者 JIANG HONG-BIAO 《Communications in Mathematical Research》 CSCD 2009年第4期289-298,共10页
In order to obtain much faster convergence, Miiller introduced the left Gamma quasi- interpolants and obtained an approximation equivalence theorem in terms of 2r wφ (f,t)p. Cuo extended the MiiUer's results to w... In order to obtain much faster convergence, Miiller introduced the left Gamma quasi- interpolants and obtained an approximation equivalence theorem in terms of 2r wφ (f,t)p. Cuo extended the MiiUer's results to wφ^24 (f, t)∞. In this paper we improve the previous results and give a weighted approximation equivalence theorem. 展开更多
关键词 Gamma operator quasi-interpolant weighted approximation modulus of smoothness derivative
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Classification of submucosal tumors in the gastrointestinal tract 被引量:44
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作者 Laura Graves Ponsaing Katalin Kiss Mark Berner Hansen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第24期3311-3315,共5页
This review is part two of three, which will present an update on the classification of gastrointestinal submucosal tumors. Part one treats of the diagnosis and part three of the therapeutic methods regarding gastroin... This review is part two of three, which will present an update on the classification of gastrointestinal submucosal tumors. Part one treats of the diagnosis and part three of the therapeutic methods regarding gastrointestinal submucosal tumors. In the past there has been some confusion as to the classification of gastrointestinal submucosal tumors. Changes in classifications have emerged due to recent advances in mainly immunohistochemistry and electron microscopy. The aim of this paper is to update the reader on the current classification. Literature searches were performed to find information related to classification of gastrointestinal submucosal tumors. Based on these searches the twelve most frequent submucosal tumor types were chosen for description of their classification. The factors that indicate whether tumors are benign or malignant are mainly size and number of mitotic counts. Gastrointestinal stromal tumors are defined mainly by their CD117 positivity. In the future, there should be no more confusion between gastrointestinal stromal tumors and other types of submucosal tumors. 展开更多
关键词 Submucosal tumor IMMUNOHISTOCHEMISTRY smooth muscle derived submucosal tumors Submucosal tumors of neurogenic origin Gastrointestinal stromal tumor MALIGNANT BENIGN
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Smooth pulse recovery based on hybrid wavelet threshold denoising and first derivative adaptive smoothing filter 被引量:3
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作者 Xinlei Qian Wei Fan +1 位作者 Xinghua Lu Xiaochao Wang 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2021年第2期17-25,共9页
Based on the pulse-shaping unit in the front end of high-power laser facilities,we propose a new hybrid scheme in a closed-loop control system including wavelet threshold denoising for pretreatment and a first derivat... Based on the pulse-shaping unit in the front end of high-power laser facilities,we propose a new hybrid scheme in a closed-loop control system including wavelet threshold denoising for pretreatment and a first derivative adaptive smoothing filter for smooth pulse recovery,so as to effectively restrain the influence of electrical noise and FM-to-AM modulation in the time–power curve,and enhance the calibration accuracy of the pulse shape in the feedback control system.The related simulation and experiment results show that the proposed scheme can obtain a better shaping effect on the high-contrast temporal shape in comparison with the cumulative average algorithm and orthogonal matching pursuit algorithm combined with a traditional smoothing filter.The implementation of the hybrid scheme mechanism increased the signal-to-noise ratio of the laser pulse from about 11 dB to 30 dB,and the filtered pulse is smooth without modulation,with smoothness of about 98.8%. 展开更多
关键词 first derivative adaptive smoothing filter recovery of smooth pulse signal-to-noise ratio wavelet threshold denoising
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Rapid determination of production date for green tea by near-infrared spectroscopy 被引量:2
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作者 ZHUANG Xin-gang WANG Li-li +3 位作者 SHI Xue-shun WANG Heng-fei CHEN Qi FANG Jia-xiong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第2期199-204,共6页
Coupled with partial least squares(PLS),near infrared(NIR)spectroscopy was applied to develop a fast and nondestructive method to identify the production date of Rizhao green tea aiming at the deficiencies of the exis... Coupled with partial least squares(PLS),near infrared(NIR)spectroscopy was applied to develop a fast and nondestructive method to identify the production date of Rizhao green tea aiming at the deficiencies of the existing methods.In the modeling process,the raw spectra were first processed by five-point smoothing and first derivative.And then,moving window back propagation artificial neural network(MW-BP-ANN)was applied to select the characteristic spectral variables.After that,the calibration model was built by PLS,and the optimum model was achieved when 9 principal component scores(PCs)were included.The performances of the calibration models were evaluated according to root mean square error of predictionεRMSEP,correlation coefficient(C p)and residual prediction deviation(σRPD).The optimum results of the calibration model was achieved,andεRMSEP=19.965,C p=0.943 andσRPD=3.07.The overall results sufficiently demonstrate that NIR spectroscopy combined with PLS can be efficiently applied in the rapid identification of green tea production date. 展开更多
关键词 near-infrared(NIR)spectroscopy production date of Rizhao green tea partial least squares(PLS) five-point smoothing and first derivative
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