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China Communications 2022年第8期19卷 234-246页

作者： jing Fang jing Xiao Xu Wang dan Chen Ruimin Hu National Engineering Research Center for Multimedia Software School of Computer ScienceWuhan UniversityWuhan 430072China Collaborative Innovation Center of Geospatial Technology Wuhan 430079China National University of Defense Technology Wuhan 430015China

Recently,satellite imagery has been widely applied in many ***,due to the limitations of hardware equipment and transmission bandwidth,the images received on the ground have low resolution and weak *** addition,since ground terminals have various resolutions and real-time playing requirements,it is essential to achieve arbitrary scale super-resolution(SR)of satellite *** this paper,we propose an arbitrary scale SR network for satellite image ***,we propose an arbitrary upscale module for satellite imagery that can map low-resolution satellite image features to arbitrary scale enlarged SR ***,we design an edge reinforcement module to enhance the highfrequency details in satellite images through a twobranch ***,extensive upsample experiments on WHU-RS19 and NWPU-RESISC45 datasets and subsequent image segmentation experiments both show the superiority of our method over the counterparts.

关键词： satellite imagery super resolution arbitrary upscale edge reinforcement video satellite

Global cavitation and hydrodynamic characteristics of a composite propeller in non-uniform wake

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Journal of Hydrodynamics 2023年第3期35卷 498-515页

作者： dan-dan Zhang Lu-lu Dong Qin Wu jing Zhang Guo-yu Wang School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China China Academy of Launch Vehicle Technology Systems Engineering Division Beijing 100076China

The composite propeller has attracted much interest due to its excellent mechanical properties such as high specific stiffness and high specific strength,hence there is an increasing interest in utilizing the composite materials to improve the hydrodynamic and structural performance of marine *** objective of this paper is to study the cavitation performance of composite propellers based on the unsteady simulation method considering the cavitation-composite structure *** typical cavitation patterns around the composite propeller are studied,which include blade sheet cavitation and tip vortex *** unsteady flow characteristics of tip vortex cavitation and structural dynamic response of composite propeller are studied,and the mechanism of composite propeller for the cavitation suppression and efficiency improvement is *** results show that compared with rigid propellers,composite propellers have smaller cavity volume and higher propulsion efficiency under the same *** unsteady cavitating flow characteristics under non-uniform wake are periodic,and the phase lag of hydrodynamic coefficients of composite propeller can be observed compared with that of the rigid *** bending-torsional coupling deformation of the composite propeller makes the pressure pulsation of the flow field gentler,which reduces the influence of the cavitation load on the composite propeller.

关键词： Composite propeller unsteady cavitation hydrodynamic characteristics fluid-structure interaction(FSI)

TRAF7 negatively regulates the RLR signaling pathway by facilitating the K48-linked ubiquitination of TBK1

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Virologica Sinica 2023年第3期38卷 419-428页

作者： jing-Ping Huang Ya-Xian Yang Tian Chen dan-dan Wang jing Li Liang-Guo Xu College of Life Science Jiangxi Normal UniversityNanchang330022China

TANK-binding kinase 1(TBK1)is a nodal protein involved in multiple signal transduction *** RNA virus-mediated innate immunity,TBK1 is recruited to the prion-like platform formed by MAVS and subsequently activates the transcription factors IRF3/7 and NF-κB to produce type I interferon(IFN)and proinflammatory cytokines for the signaling *** this study,TRAF7 was identified as a negative regulator of innate immune ***7 interacts with TBK1 and promotes K48-linked polyubiquitination and degradation of TBK1 through its RING domain,impairing the activation of IRF3 and the production of IFN-β.In addition,we found that the conserved cysteine residues at position 131 of TRAF7 are necessary for its function toward *** of TRAF7 could facilitate the activation of IRF3 and increase the transcript levels of downstream antiviral *** data suggest that TRAF7 negatively regulates innate antiviral immunity by promoting the K48-linked ubiquitination of TBK1.

关键词： TANK-Binding kinase 1(TBK1) Type I interferon TRAF7 Ubiquitination Innate immunity

Correlation of dynamic contrast-enhanced ultrasonography and the Ki-67 labelling index in pancreatic ductal adenocarcinoma

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World Journal of Gastroenterology 2024年第44期30卷 4697-4708页

作者： Xiao-jing Lin Shu Zhu dan Wang jing-Yuan Chen Su-Xian Wei Shi-Yun Chen Hong-chang Luo Department of Medical Ultrasound Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is a highly malignant and aggressive tumor,and high Ki-67 expression indicates poor histological differentiation and ***,one of the challenges in diagnosing preoperatively patients with PDAC is predicting the degree of *** contrast-enhanced ultrasonography(DCE-US)plays a crucial role in abdominal tumor diagnosis,and can adequately show the microvascular composition within the ***,the relationship between DCE-US and the Ki-67 labelling index remains unclear at the present *** To predict the correlation between Ki-67 expression and the parameters of *** Patients with PDAC who underwent DCE-US were retrospectively *** who had received any treatment(radiotherapy or chemotherapy)prior to DCE-US;had incomplete clinical,imaging,or pathologic information;and had poor-quality image analysis were *** between Ki-67 expression and the parameters of DCE-US in patients with PDAC were assessed using Spearman’s rank correlation *** diagnostic performances of these parameters in high Ki-67 expression group were evaluated according to receiver operating characteristic *** Based on the Ki-67 labelling index,30 patients were divided into two groups,i.e.,the high expression group and the low expression *** the relative quantitative parameters between the two groups,relative half-decrease time(rHDT),relative peak enhancement,relative wash-in perfusion index and relative wash-in rate were significantly different between two groups(P=0.018,P=0.025,P=0.028,P=0.035,respectively).The DCE-US parameter rHDT was moderately correlated with Ki-67 expression,and rHDT≥1.07 was more helpful in accurately diagnosing high Ki-67 expression,exhibiting a sensitivity and specificity of 53.8%and 94.1%,*** One parameter of DCE-US,rHDT,correlates with high Ki-67 *** demonstrates that parameters obtained noninvasively

关键词： Pancreatic ductal adenocarcinoma Dynamic contrast-enhanced ultrasonography Ki-67 antigen Quantitative analysis Prognostic situation

Symmetry groups and Gauss kernels of Schrdinger equations

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Chinese Physics B 2012年第2期21卷 66-75页

作者： Kang jing Qu chang-Zheng Department of Mathematics Northwest UniversityXi'an 710069China Department of Mathematics Ningbo UniversityNingbo 315211China

The relationship between symmetries and Gauss kernels for the SchrSdinger equation iut = uxx ＋ f（x）u is established. It is shown that if the Lie point symmetries of the equation are nontrivial, a classical integral transformations of the Gauss kernels can be obtained. Then the Gauss kernels of Schroedinger equations are derived by inverting the integral transformations. Furthermore, the relationship between Gauss kernels for two equations related by an equivalence transformation is identified.

关键词： Schroedinger equation symmetry group Gauss kernel equivalence transformation

Debris Flow Susceptibility Assessment Using a Probabilistic Approach:A Case Study in the Longchi Area, Sichuan Province, China

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Journal of Mountain Science 2014年第4期11卷 1001-1014页

作者： chang Ming TANG Chuan ZHANG dan-dan MA Guo-chao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology

The Longchi area with the city of Dujiangyan, in the Sichuan province of China, is composed of Permian stone and diorites and Triassic sandstones and mudstones intercalated with slates. An abundance of loose co-seismic materials were present on the slopes after the May 12, 2008 Wenchuan earthquake, which in later years served as source material for rainfall-induced debris flows or shallow landslides. A total of 48 debris flows, all triggered by heavy rainfall on 13th August 20l0, are described in this paper. Field investigation, supported by remote sensing image interpretation, was conducted to interpret the co-seismic landslides in the debris flow gullies. Specific characteristics of the study area such as slope, aspect, elevation, channel gradient, lithology, and gully density were selected for the evaluation of debris flow susceptibility. A score was given to all the debris flow gullies based on the probability of debris flow occurrence for the selected factors. In order to get the contribution of the different factors, principal component analyses were applied. A comprehensive score was obtained for the 48 debris flow gullies which enabled us to make a susceptibility map for debris flows with three classes. Twenty-two gullies have a high susceptibility, twenty gullies show a moderate susceptibility and six gullies have a low susceptibility for debris flows.

关键词： Debris flow Landslide Probability Susceptibility assessment Grey correlation

Nonlocal Symmetries to Systems of Nonlinear Diffusion Equations

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Communications in Theoretical Physics 2008年第1期49卷 9-16页

作者： QU chang-Zheng KANG jing Center for Nonlinear Studies Northwest University Xi＇an 710069 China Department of Mathematics Northwest University Xi＇an 710069 China

In this paper, we study potential symmetries to certain systems of nonlinear diffusion equations. Thosesystems have physical applications in soil science, mathematical biology, and invariant curve flows in R^3. Lie point symmetries of the potential system, which cannot be projected to vector fields of the given dependent and independent variables, yield potential symmetries. The class of the system that admits potential symmetries is expanded.

关键词： symmetry group system of nonlinear diffusion equation nonlocal symmetry

A Formula of General Solution for a Class of Homogeneous Trinomial Recurrence of Variable Coefficients with Two Indices

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Wuhan University Journal of Natural Sciences 2005年第5期10卷 828-832页

作者： YU dan YU chang-an School of Computer Wuhan University Wuhan 430072 Hubei China School of Mathematics and Statistics Wuhan University Wuhan 430072 Hubei China

In practice, it is very difficult to find the solution of recurrence relation by using the characteristic roots. By applying iteration and induction we present an explicit formula of general solution for a class of homogeneous trinomial recurrence of variable coefficients with two indices. It provides a concrete and applicable model to solve the relevant problem with computer.

关键词： a formula of general solution homogeneous trinomial recurrence variable coefficients two indices

A Robust Algorithm for Blind Total Variation Restoration

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 681-690页

作者： jing Xu Qian-shun chang School of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Deijing 100190 China

Image restoration is a fundamental problem in image processing. Blind image restoration has a great value in its practical application. However, it is not an easy problem to solve due to its complexity and difficulty. In this paper, we combine our robust algorithm for known blur operator with an alternating minimization implicit iterative scheme to deal with blind deconvolution problem, recover the image and identify the point spread function（PSF）. The only assumption needed is satisfy the practical physical sense. Numerical experiments demonstrate that this minimization algorithm is efficient and robust over a wide range of PSF and have almost the same results compared with known PSF algorithm.

关键词： Blind deconvolution total variation algebraic multigrid method Krylov acceleration