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Rare Metals 2020年第4期39卷 352-367页

作者： wei-wei Zhang Zhi-yuan wei Li-yuan Zhang Ya-Zhe Xing Qiang Zhang School of Materials Science and Engineering Chang'an UniversityXi'an 710064China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi'an 710049China College of Chemistry and Chemical Engineering Neijiang Normal UniversityNeijiang 641112China AECC Beijing Institute of Aeronautical Material Beijing 100095China

High-insulation,long-life thermal barrier coatings(TBCs)decrease the service temperature of superalloys and improve the service life of gas *** in the thermal insulation properties of the coating mainly depends on the optimization of the TBC *** important challenge for TBCs is maintaining a high performance during thermal exposure without degradation,as the pore-rich structure of the topcoat would inevitably be transformed by sintering.A low-thermalconductivity anti-sintering coating can overcome the tradeoff between thermal insulation and sinter *** this review,the design,preparation,and serviceability evaluation of a low-thermal-conductivity anti-sintering coating will be ***,directions for potential development are *** paper provides a comprehensive understanding of the structured tailoring of TBCs for better thermal insulation and anti-sintering performance.

关键词： Thermal barrier coatings Multi-scale pore Sintering resistance Low thermal conductivity

Fully automatic DOM generation method based on optical flow field dense image matching

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Geo-Spatial Information Science 2023年第2期26卷 242-256页

作者： wei yuan Xiuxiao yuan Yang Cai Ryosuke Shibasaki School of Remote Sensing and Information Engineering Wuhan UniversityWuhanChina Center for Spatial Information Science University of TokyoKashiwaJapan

Automatic Digital Orthophoto Map(DOM)generation plays an important role in many downstream works such as land use and cover detection,urban planning,and disaster *** DOM generation methods can generate promising results but always need ground object filtered DEM generation before otho-rectification;this can consume much time and produce building facade contained *** address this problem,a pixel-by-pixel digital differential rectification-based automatic DOM generation method is proposed in this ***,3D point clouds with texture are generated by dense image matching based on an optical flow field for a stereo pair of images,***,the grayscale of the digital differential rectification image is extracted directly from the point clouds element by element according to the nearest neighbor method for matched ***,the elevation is repaired grid-by-grid using the multi-layer Locally Refined B-spline(LR-B)interpolation method with triangular mesh constraint for the point clouds void area,and the grayscale is obtained by the indirect scheme of digital differential rectification to generate the pixel-by-pixel digital differentially rectified image of a single image ***,a seamline network is automatically searched using a disparity map optimization algorithm,and DOM is smartly *** qualitative and quantitative experimental results on three datasets were produced and evaluated,which confirmed the feasibility of the proposed method,and the DOM accuracy can reach 1 Ground Sample Distance(GSD)*** comparison experiment with the state-of-the-art commercial softwares showed that the proposed method generated DOM has a better visual effect on building boundaries and roof completeness with comparable accuracy and computational efficiency.

关键词： Digital Orthophoto Map(DOM) dense image matching based on optical flow field(OFFDIM) 3D point clouds with texture seamline network accuracy

Cyclodextrin-functionalized Ordered Porous Block Copolymer Films: Preparation and Property

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Chinese Journal of Polymer Science 2018年第1期36卷 34-42页

作者： Jing Dang yuan-wei Su wei Tian Ministry of Education Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Macromolecular Science and Technology School of Science Northwestern Polytechnical University

Ordered porous block copolymer films（PBCFs） have attracted much attention because of their potential applications in several fields. In this paper, we first reported a non-destructive, controllable, and efficient approach for preparation of β-cyclodextrin（β-CD）-functionalized PBCFs（β-CD-PBCFs）. The key point of the approach is to incorporate β-CD units into the hydrophilic segment of amphiphilic block copolymers before the preparation of films. β-CD-PBCFs with structural integrity and controllable pore parameters were fabricated through combining of self-assembly and breath figure methods. And then, the effective adsorption capacity of β-CD-PBCFs toward Congo red was confirmed through UV-Vis spectroscopy and was found to be affected by β-CD content and solution p H values. Adsorption kinetic results showed that the adsorption behavior of β-CD-PBCFs was consistent with the pseudo-second-order kinetic model and the chemisorption mechanism.

关键词： Porous block copolymer film β-Cyclodextrin Breath figure Self-assembly

Earthquake-induced collapse mechanism of two types of dangerous rock masses

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 379-386页

作者： Wang wei yuan wei Wang Qizhi Xue Kang School of Civil Engineering Shijiazhuang Railway Institute Geotechnical Institute Civil Engineering Department Tianjin University

As the economy of China develops, an increasing number of key traffic projects have been undertaken in the west of China, where there are high, steep rock slopes. The collapse of dangerous rock masses, especially following a strong earthquake, is one of common geological disasters known in rock slope engineering. Therefore, it is important to study the collapse mechanism of dangerous rock masses induced by an earthquake and the analysis approach of its stability. This study provides a simple and convenient method to determine the collapse mechanisms of two types of dangerous rock masses （i.e. cantilever and upright） associated with the definition and calculation of the safety factor, which is based on the flexure theory of a constant-section beam by combining with the maximum tensile-stress criterion to depict the process of crack propagation caused by seismic waves. The calculation results show that there are critical crack depths in each form of the dangerous rock masses. Once the accumulated depth of the crack growth during an earthquake exceeds the critical depth, the collapse will occur. It is also demonstrated that the crack extension amount of each step is not a constant value, and is closely associated with the current accumulated crack depth. The greater the cumulative crack depth, the more easily the crack propagates. Finally, the validity and applicability of the proposed method are verified through two actual engineering examples.

关键词： dangerous rock mass earthquake-induced collapse cantilever beam theory safety factor high-steep rock slope

Numerical investigation on the effects of current headings on vortex induced motions of a semi-submersible

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Journal of Hydrodynamics 2022年第3期34卷 382-394页

作者： wei-wen Zhao Zhi-yuan wei De-cheng Wa Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Marine Design&Research Institute of China Shanghai200011China Ocean College Zhejiang UniversityZhoushan316021China

In this paper,numerical simulations on vortex-induced motions(VIM)of a semi-submersible at two different current headings are conducted over a wide range of current *** simulations are performed with the computational fluid dynamics(CFD)solver VIM-FOAM-SJTU which is an in-house solver developed based on the OpenFOAM *** turbulent flows are resolved with a shear stress transport-delayed detached eddy simulation(SST-DDES)*** decay tests for transverse and yaw motion are performed in calm still water to make sure the equivalent stiffness is setup *** the results of VIM,including motion response,forces and moments,and flow patterns are presented and analyzed *** including transverse,in-line and yaw motion at different current headings and velocities are *** vorticity in the wake regions at different time stamps are also illustrated for different current headings and velocities.

关键词： Vortex-induced motions(VIM) vortex-induced yaw vim-FOAM-SJTU solver Reynolds stress

Superlinear Elliptic Equation with Mixed Boundary Value in Annular Domain

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Acta Mathematica Sinica,English Series 2021年第10期37卷 1549-1559页

作者： Jian TIAN yuan Hong wei School of Mathematics Jilin UniversityChangchun 130012P.R.China

In this paper,we study superlinear elliptic equations with mixed boundary value conditions in annular *** is assumed that the nonlinearities depend on the derivative *** results about existence of solutions are establ... 详细信息

关键词： Mixed boundary value annular domain radial solution gradient term iterative method

ACCELERATION METHODS OF NONLINEAR ITERATION FOR NONLINEAR PARABOLIC EQUATIONS

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Journal of Computational Mathematics 2006年第3期24卷 412-424页

作者： Guang-wei yuan Xu-deng Hang Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009 Beijing 100088 China

This paper discusses the accelerating of nonlinear parabolic equations. Two iterative methods for solving the implicit scheme new nonlinear iterative methods named by the implicit-explicit quasi-Newton （IEQN） method and the derivative free implicit-explicit quasi-Newton （DFIEQN） method are introduced, in which the resulting linear equations from the linearization can preserve the parabolic characteristics of the original partial differential equations. It is proved that the iterative sequence of the iteration method can converge to the solution of the implicit scheme quadratically. Moreover, compared with the Jacobian Free Newton-Krylov （JFNK） method, the DFIEQN method has some advantages, e.g., its implementation is easy, and it gives a linear algebraic system with an explicit coefficient matrix, so that the linear （inner） iteration is not restricted to the Krylov method. Computational results by the IEQN, DFIEQN, JFNK and Picard iteration methods are presented in confirmation of the theory and comparison of the performance of these methods.

关键词： Nonlinear parabolic equations Difference scheme Newton iterative methods.

Carbon Dots Intensified Mechanochemiluminescence from Waterborne Polyurethanes as Tunable Force Sensing Materials

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Chinese Journal of Polymer Science 2021年第11期39卷 1403-1411页

作者： Bo-Han Cao Wu Chen Wan-yuan wei Yu-Lan Chen yuan yuan Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistryTianjin UniversityTianjin 300354China

1,2-Dioxetane is a well-known chemiluminescent mechanophore allowing real-time monitoring of polymer chain scission,but usually suffers from fluorescence quenching in polar ***,a series of mechanochemiluminescent waterborne polyurethanes/carbon dots composites(WPU-CDs)have been synthesized by incorporating fluorescent CDs to promote the energy transfer process in different *** resulting bulk WPUs,and in particular,their swollen films filled with a large amount of polar solvents(water and ionic liquid)emit intense *** force-induced covalent bond scission and stress distribution within these different WPU-CDs films can be sensitively ***,the ionic liquid containing films exhibited both electrical and luminescent signal changes under stretching,which offer a new kind of force sensor responsive at a broad detecting strain range and for multi-mode strain *** study is expected to stimulate new research endeavors in mechanistic insight on waterborne polyurethanes and the corresponding stretchable sensing devices.

关键词： Polymer mechanochemistry Mechanochemiluminescence Waterborne polyurethane Carbon dots Force sensing

Adaptive beam forming for time-variant channels with a multi-beam antenna

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 37-40页

作者： JIANG Ze MEI yuan-yuan RUAN wei College of Electronic Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China

A multi-beam adaptive antenna is investigated by considering the adaptive beam forming performance for time-variant channels on the focus of mobile to base station or reverse link. This antenna is constructed by Fresnel zone phase-correcting plane （FZP） focusing element and uniformly spaced feeds array. An estimator for the beamforming weight vector in the presence of angle spreads is derived using a code filtering approach. Owing to the time-varying nature of the channels, a recursive method for computing and tracking the above optimal weight vector solution that is easy to implement is applied. The effects of angle spread, maximum Doppler frequency, and forgetting factor are studied. Simulation results showed that this type of adaptive antenna is capable of performing adaptive beam forming for time-variant channels effectively.

关键词： adaptive antenna adaptive beam forming FZP mismatch loss

Pairing symmetry in monolayer of orthorhombic CoSb

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Frontiers of physics 2021年第4期16卷 185-194页

作者： Tian-Zhong yuan Mu-yuan Zou Wen-Tao Jin Xin-yuan wei Xu-Guang Xu wei Li State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China Key Laboratory of Micro-Nano Measurement-Manipulation and Physics(Ministry of Education) School of PhysicsBeihang UniversityBeijing 100191China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Ferromagnetism and superconductivity are generally considered to be antagonistic phenomena in condensed matter ***,we theoretically study the interplay between the ferromagnetic and superconducting orders in a recent discovered monolayered CoSb superconductor with an orthorhombic symmetry and net magnetization,and demonstrate the pairing symmetry of CoSb as a candidate of non-unitary superconductor with time-reversal symmetry *** performing the group theory analysis and the first-principles calculations,the superconducting order parameter is suggested to be a triplet pairing with the irreducible representation of 3B2u,which displays intriguing nodal points and non-zero periodic modulation of Cooper pair spin polarization on the Fermi surface *** findings not only provide a significant theoretical insight into the coexistence of superconductivity and ferromagnetism,but also reveal the exotic spin polarized Cooper pairing driven by ferromagnetic spin fluctuations in a triplet superconductor.

关键词： superconductivity ferromagnetism non-unitary pair