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Chinese Chemical Letters 2011年第11期22卷 1359-1362页

作者： Qiang li Min gu State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam Key Lab for the Exploitation of Southwestern Resources and the Environmental Disaster Control Engineering of Education Ministry College of Resources and Environmental Science Chongqing University Chongqing 400044 China

TeOx-SiO2 composite films having third-order nonlinearities were prepared by electrochemically induced sol-gel deposition method on ITO *** third-order optical nonlinearities of the films were measured by Z-scan *** third-order nonlinear susceptibilities（χ^（（3））） of the as-prepared films are 5.9×10^（-7） to 4.29×10^（-6）*** surface morphology and composition of the films were characterized by SEM/EDX,which identified that Te metallic particles well dispersed in TeO_x-SiO_2 gel films.

关键词： TeOx-SiO2 composite Electrochemically induced sol-gel method Third-order nonlinearities Z-scan

Synthesis and theoretical study of first generation CCK-functional dendrimers

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Chinese Chemical Letters 2007年第12期18卷 1505-1508页

作者： gu He li guo Key Laboratory of Drug Targeting of Ministry of Education and Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041 China

A convenient synthesis and theoretical study of five CCK-functional dendrimers is described. The dendritic cores were linked with the CCK（Trp-Met-Asp（OBn）-PheNH2） fragment by forming amide bonds to give five target molecules. The structures of CCK-functional dendrimers were characterized by NMR, MS spectrum and predicted using molecular mechanics and PM3 semi- empirical molecular orbital theory.

关键词： Dendrimer CCK Synthesis Molecular mechanics Semi-empirical molecular orbital theory

Truncated sparse approximation property and truncated q-norm minimization

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Applied Mathematics(A Journal of Chinese Universities) 2019年第3期34卷 261-283页

作者： CHEN Wen-gu li Peng Institute of Applied Physics and Computational Mathematics Beijing100088China Graduate School China Academy of Engineering PhysicsBeijing 100088China

This paper considers approximately sparse signal and low-rank matrix’s recovery via truncated norm minimization minx∥xT∥q and minX∥XT∥Sq from noisy *** first introduce truncated sparse approximation property,a more general robust null space property,and establish the stable recovery of signals and matrices under the truncated sparse approximation *** also explore the relationship between the restricted isometry property and truncated sparse approximation *** we also prove that if a measurement matrix A or linear map A satisfies truncated sparse approximation property of order k,then the first inequality in restricted isometry property of order k and of order 2k can hold for certain different constantsδk andδ2k,***,we show that ifδs(k+|T^c|)linear map A satisfy truncated sparse approximation property of order *** should be pointed out that when Tc=Ф,our conclusion implies that sparse approximation property of order k is weaker than restricted isometry property of order sk.

关键词： truncated norm minimization truncated sparse approximation property restricted isometry property sparse signal recovery low-rank matrix recovery Dantzig selector

The utility of two-dimensional shear wave elastography and texture analysis for monitoring liver fibrosis in rat model

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 46-52页

作者： li-Hong gu guang-Xiang gu Ping Wan Feng-Hua li Qiang Xia Department of liver Surgery Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200127China Department of Ultrasound Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200127China

Background:liver fibrosis is a common pathological change caused by a variety of *** diagnosis and timely treatment can reverse or delay disease progression and improve the *** study aimed to assess the potential utility of two-dimensional shear wave elastography and texture analysis in dynamic monitoring of the progression of liver fibrosis in rat ***:Twenty rats were divided into control group(n=4)and experimental groups(n=4 per group)with carbon tetrachloride administration for 2,3,4,and 6 *** liver stiffness measurement was performed by two-dimensional shear wave elastography,while the optimal texture analysis subsets to distinguish fibrosis stage were generated by *** results of elastography and texture analysis were validated through comparing with ***:liver stiffness measurement was 6.09±0.31 kPa in the control group and 7.10±0.41 kPa,7.80±0.93 kPa,8.64±0.93 kPa,9.91±1.13 kPa in the carbon tetrachloride induced groups for 2,3,4,6 weeks,respectively(Pnalysis,histogram and co-occurrence matrix had the most frequency texture parameters in staging liver *** operating characteristic curve of liver elasticity showed that the sensitivity and specificity were 95.0%and 92.5%to discriminate liver fibrosis and non-fibrosis,*** texture analysis,five optimal parameters were selected to classify liver fibrosis and ***:Two-dimensional shear wave elastography showed potential applications for noninvasive monitoring of the progression of hepatic fibrosis,even in mild *** analysis can further extract and quantify the texture features in ultrasonic image,which was a supplementary to further visual information and acquired high diagnostic accuracy for severe fibrosis.

关键词： Shear wave elastography Ultrasound Texture analysis Fibrosis Rat

Valuation of Futures Options with Initial Margin Requirements and Daily Price limit

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Acta Mathematica Sinica,English Series 2010年第3期26卷 579-586页

作者： Juan li Yan ling gu School of Mathematics and Statistics Shandong University at Weihai Weihai 264209 P. R. China Treasury Department China Everbright Bank Beijing 100045 P. R. China

The paper presents a valuation model of futures options trading at exchanges with initial margin requirements and daily price limit, and this result gives an academic guidance to design trading rules at exchanges. Unlike the leading work of Black, certain trading rules are considered so as to be more fit for practical futures markets. The paper prices futures options with initial margin requirements and daily price limit by duplicating them with the help of the theory of backward stochastic differential equations （BSDEs, for short）. Furthermore, an explicit expression of the price Of the call （or the put） futures option is given and also is shown to be the unique solution of the associated nonlinear partial differential equation.

关键词： valuation of futures option initial margin requirements daily price limit backward stochastic differential equations

Identification and fine mapping of PmNJ3946 for powdery mildew resistance in einkorn wheat

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The Crop Journal 2023年第6期11卷 1846-1851页

作者： Peisi Wang Jun Huang na li Jie Zhang Caimei gu Yang Yuan Ziruo Wen Haiyan Jia Zhongxin Kong Zhengqiang Ma Crop Genomics and Bioinformatics Center and national Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural UniversityNanjing 210095JiangsuChina Zhongshan Biological Breeding Laboratory Nanjing 210014JiangsuChina

Powdery mildew caused by Blumeria graminis ***(Bgt)is a destructive wheat *** it can be easily overcome by deployment of resistance genes,the resistance is often quickly compromised by pathogen ***,exploration and characterization of new resistance genes is always *** NJ3946 derived from a cross of einkorn wheat accessions TA2032 and M389 showed resistance to powdery *** analysis of an F2 population derived from a cross of NJ3946 and M389 suggested that the resistance was conferred by a dominant *** polymorphic markers identified through bulked segregant analysis(BSA),this gene was mapped to a novel locus on chromosome 3A,and was designated as *** segregant Rna-seq analysis(BSR-seq)was conducted to obtain more closely linked markers,which allowed delimitation of the PMNJ3946 locus to a 0.9 cM interval covering a physical distance of less than 1 ***3946 was flanked by Xwgrc5153 and SNP-derived marker CHS21_3A008915069,and co-segregated with SNP-derived markers CHS21_3A008939814 and CHS21_*** PmNJ3946 discovery expands the diversity of powdery mildew resistance genes and is useful for wheat breeding.

关键词： Powdery mildew Disease resistance Genetic mapping Triticum monococcum PmNJ3946

Sentiment analysis using deep learning approaches:an overview

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Science China(Information Sciences) 2020年第1期63卷 21-56页

作者： Olivier HABIMAna Yuhua li Ruixuan li Xiwu gu Ge YU School of Computer Science and Technology Huazhong University of Science and Technology School of Computer Science and Engineering Northeastern University

Nowadays, with the increasing number of Web 2.0 tools, users generate huge amounts of data in an enormous and dynamic way. In this regard, the sentiment analysis appeared to be an important tool that allows the automation of getting insight from the user-generated data. Recently, deep learning approaches have been proposed for different sentiment analysis tasks and have achieved state-of-the-art results. Therefore, in order to help researchers to depict quickly the current progress as well as current issues to be addressed, in this paper, we review deep learning approaches that have been applied to various sentiment analysis tasks and their trends of development. This study also provides the performance analysis of different deep learning models on a particular dataset at the end of each sentiment analysis task. Toward the end, the review highlights current issues and hypothesized solutions to be taken into account in future work. Moreover, based on knowledge learned from previous studies, the future work subsection shows the suggestions that can be incorporated into new deep learning models to yield better performance. Suggestions include the use of bidirectional encoder representations from transformers(BERT), sentiment-specific word embedding models, cognition-based attention models, common sense knowledge, reinforcement learning, and generative adversarial networks.

关键词： sentiment analysis opinion mining deep learning neural network natural language processing(NLP) social network

A Self-Organizing RBF Neural Network Based on Distance Concentration Immune Algorithm

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 276-291页

作者： Junfei Qiao Fei li Cuili Yang Wenjing li Ke gu Beijing University of Technology Beijing 100083China

Radial basis function neural network(RBFNN) is an effective algorithm in nonlinear system identification. How to properly adjust the structure and parameters of RBFNN is quite challenging. To solve this problem, a distance concentration immune algorithm(DCIA) is proposed to self-organize the structure and parameters of the RBFNN in this paper. First, the distance concentration algorithm, which increases the diversity of antibodies, is used to find the global optimal solution. Secondly,the information processing strength(IPS) algorithm is used to avoid the instability that is caused by the hidden layer with neurons split or deleted randomly. However, to improve the forecasting accuracy and reduce the computation time, a sample with the most frequent occurrence of maximum error is proposed to regulate the parameters of the new neuron. In addition, the convergence proof of a self-organizing RBF neural network based on distance concentration immune algorithm(DCIA-SORBFNN) is applied to guarantee the feasibility of algorithm. Finally, several nonlinear functions are used to validate the effectiveness of the algorithm. Experimental results show that the proposed DCIASORBFNN has achieved better nonlinear approximation ability than that of the art relevant competitors.

关键词： Distance concentration immune algorithm(DCIA) information processing strength(IPS) radial basis function neural network(RBFNN)

A speckle noise suppression method based on surface waves investigation and monitoring data

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Acta Oceanologica Sinica 2023年第1期42卷 131-141页

作者： Jingwei gu Xiuzhong li Yijun He School of Marine Sciences Nanjing University of Information Science&TechnologyNanjing210044China

The internal energy distribution of waves can be described using ocean-wave *** many ways,obtaining wave spectra on a global scale is *** waves investigation and monitoring onboard the Chinese-French oceanography satellite is the first space-borne instrument for detecting wave spectra specially,which was launched on October 29,*** can avoid the shortage of synthetic aperture radar detection results while still having some problems,especially with the effects of speckle *** this study,a method to suppress the speckle noise is ***,the empirical formula for background speckle noise is ***,many spatio-temporal representative fluctuation spectra are classified and ***,rational transfer function filtering is used to obtain speckle noise close to the along-track ***,a signal-to-noise ratio threshold is used to suppress the abnormal speckle *** method solves the problems existing in previous denoising methods,such as excessive denoising in the along-track direction and the inability of some abnormal noises to be denoised in the two-dimensional directional wave spectra.

关键词： speckle noise surface waves investigation and monitoring WaveWatch III wave spectra

Environmental Conditions Conducive to the Formation of Multiple Tropical Cyclones over the Western North Pacific

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Advances in Atmospheric Sciences 2024年第10期41卷 2027-2042页

作者： Yining gu Ruifen ZHAN Xiaomeng li Department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China CMA-FDU Joint Laboratory of Marine Meteorology Shanghai 200030China Institute of Desert and Meteorology China Meteorological AdministrationUrumqi 830002China

There is limited understanding regarding the formation of multiple tropical cyclones(MTCs).This study explores the environmental conditions conducive to MTC formation by objectively determining the atmospheric circulation patterns favorable for MTC formation over the western North *** on 199 MTC events occurring from June to October 1980–2020,four distinct circulation patterns are identified:the monsoon trough(MT)pattern,accounting for 40.3%of occurrences,the confluence zone(CON)pattern at 26.2%,the easterly wave(EW)pattern at 17.8%,and the monsoon gyre(MG)pattern at 15.7%.The MT pattern mainly arises from the interaction between the subtropical high and the monsoon trough,with MTCs forming along the monsoon trough and its *** CON pattern is affected by the subtropical high,the South Asian high,and the monsoon trough,with MTCs emerging at the confluence zone where the prevailing southwesterly and southeasterly flows *** EW pattern is dominated by easterly flows,with MTCs developing along the easterly wave *** in the MG pattern arise within a monsoon vortex characterized by strong southwesterly flows.A quantitative analysis further indicates that MTC formation in the MT pattern is primarily governed by mid-level vertical velocity and low-level vorticity,while mid-level humidity and vertical velocity are significantly important in the other *** meridional shear and convergence of zonal winds are essential in converting barotropic energy from the basic flows to disturbance kinetic energy,acting as the primary source for eddy kinetic energy growth.

关键词： multiple tropical cyclones western North Pacific circulation pattern monsoon trough barotropic energy conversion