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Dynamic modeling and coupling characteristics of rotating inclined beams with twisted-shape sections

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Frontiers of Mechanical Engineering 2020年第3期15卷 374-389页

作者： jin zeng Chenguang ZHAO Hui MA Bangchun WEN School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education Northeastern UniversityShenyang 110819China

In the existing literature, most studies investigated the free vibrations of a rotating pre-twisted cantilever beam;however, few considered the effect of the elastic-support boundary and the quantification of modal coupling degree among different vibration directions. In addition, Coriolis, spin softening, and centrifugal stiffening effects are not fully included in the derived equations of motion of a rotating beam in most literature, especially the centrifugal stiffening effect in torsional direction. Considering these deficiencies, this study established a coupled flapwise–chordwise–axial–torsional dynamic model of a rotating double-tapered, pre-twisted, and inclined Timoshenko beam with elastic supports based on the semi-analytic method. Then, the proposed model was verified with experiments and ANSYS models using Beam188 and Shell181 elements. Finally, the effects of setting and pre-twisted angles on the degree of coupling among flapwise, chordwise, and torsional directions were quantified via modal strain energy ratios. Results showed that 1) the appearance of torsional vibration originates from the combined effect of flapwise–torsional and chordwise–torsional couplings dependent on the Coriolis effect, and that 2) the flapwise–chordwise coupling caused by the pure pre-twisted angle is stronger than that caused by the pure setting angle.

关键词： elastic-support boundary pre-twisted beam semi-analytic method modal strain energy ratio torsional vibration

Natural Fresh Proteins Directed Hierarchically Porous Nitrogen-doped TiO_(2) as with High Performance as Photocatalyts and Electrode Materials

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Journal of Wuhan University of Technology(Materials Science) 2021年第2期36卷 183-188页

作者： ZUO Jiaxiang jin Xin zeng Hui Wuhan Institute of Marine Electric Propulsion Wuhan 430064China

Fresh EPF proteins from Liangzi Lake were employed as a template to synthesize hierarchically porous nitrogen-doped TiO_(2) in a single *** experimental results show that N-TiO_(2) sample exhibits significantly enhanced visible-light photocatalytic activity in both chemical waste treatment and hydrogen production,and the visible-light photocatalytic activities vary with the concentrations of EPF *** optimal concentration of protein is 600 mg·mL^(-1) and the degradation of RhB could be almost completed in just 25 ***,the performance of as-synthesized TiO2 as an electrode for Li-ion battery can be also regulated by the EPF *** extrapallial fluid(EPF)proteins extracted from the same kind of mussels living in different regions have significantly different effects on the performances of TiO_(2) as electrode materials for Li-ion *** present work highlights the unimaginable effects of natural organic matrix on the synthesis of advanced materials with optimized functional properties.

关键词： N-TiO_(2) photocatalytic activity hydrogen production hierarchically porous structure extrapallial fluid(EPF)proteins

Analysis of a Hyperbolic-Parabolic Type System for Image Inpainting

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Acta Mathematica Sinica,English Series 2012年第8期28卷 1663-1676页

作者： Zheng Meng jin Xiao ping YANG School of Science Nanjing University of Posts and Telecommunications School of Science Nanjing University of Science and Technology

In this paper we consider the initial boundary value problem of a hyperbolic-parabolic type system for image inpainting in a 2-D bounded domain, and establish the existence of weak solutions to the system by employing... 详细信息

关键词： Weak solutions hyperbolic-parabolic type system vanishing viscosity image inpainting

Mann Iteration of Weak Convergence Theorems in Banach Space

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 217-224页

作者： Liang-gen Hu jin-ping Wang Department of Mathematics Ningbo University Ningbo 315211 China

In this paper, by using Mann＇s iteration process we will establish several weak convergence theorems for approximating a fixed point of k-strictly pseudocontractive mappings with respect to p in p-uniformly convex Banach spaces. Our results answer partially the open question proposed by Marino and Xu, and extend Reich＇s theorem from nonexpansive mappings to k-strict pseudocontractive mappings.

关键词： k-strictly pseudocontractive mappings Mann iteration fixed point p-uniformly convex weak convergence

Synthesis and Molecular Structure of Acetic Acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester

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Chinese Journal of Structural Chemistry 2006年第8期25卷 1014-1018页

作者： WEI Hui-Qin zeng Run-Sheng WU Gui-ping WANG Bao-An ZOU Jian-ping Key Laboratory of Organic Synthesis of Jiangsu Province College ofChemistry and Chemical Engineering Suzhou University Suzhou 215123 China

The title compound, acetic acid-3,5-diacetoxy-2-acetoxymethyl-6-（4-quinoxalin- 2-yl-phenoxy）-tetrahydro-pyran-4-yl-ester 8 （C28H28N2O10, Mr = 552.54）, has been synthesized and its crystal structure was determined by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21, a = 10.060（8）, b = 5.648（4）, c = 24.11（2）A, β = 91.078（10）°, Z = 2, V= 1369.9（19）A^3, Dc = 1.339 g/cm^3,μ（MoKa） = 1.03 cm^-1, F（000） = 580.00, T =. 193.1 Kx-9 θmax = 25.03, （△/σ）max = 0.0000, Flack = -0.0（24）, the final R = 0.0680 and wR = 0.140 （w = 1/[0.0016Fo^2 ＋ 1.00000（Fo^2）]/（4Fo^2）） for 3126 observed reflections （1 〉 20（/））. The pyranoid ring adopts chair conformation in the sugar moiety, and all of the acetyl groups are in the e bond of the pyranoid ring, so the sugar moiety is very stable.

关键词： acetic acid-3 5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester synthesis crystal structure

Effects of Phase Damping on Controlled Teleportation of a Qubit by a GHZ State

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Communications in Theoretical Physics 2008年第4期49卷 895-900页

作者： HAN Xiao-ping LIU jin-Ming State Key Laboratory of Precision Spectroscopy Department of Physics East China Normal University Shanghai 200062China

We investigate controlled teleportation ofa qubit via a GHZ state with the influence of phase damping in the Bloch sphere representation. We use the average trace distance to describe how close the output state is to the input state to be teleported. Our results show that the average trace distance is a function of decoherence rates and angles of the analyzer performed by the controller in the single-particle projective measurement. Moreover, for a fixed value of the decoherence rate, one can adjust the analyzer angle to achieve the optimal average trace distance.

关键词： controlled teleportation GHZ state phase damping trace distance

Interest rate swap pricing with default risk under variance gamma process

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Applied Mathematics(A Journal of Chinese Universities) 2017年第1期32卷 93-107页

作者： YANG Xiao-feng YU jin-ping College of Economics and Management Hangzhou Normal University Hangzhou 311121 China. Zhejiang Yongan Technology Limited Corporation Hangzhou 310014 China.

Under the assumption that the dynamic assets price follows the variance gamma process, we establish a new bilateral pricing model of interest rate swap by integrating the reduced form model for swap pricing and the structural model for default risk *** pricing model preserves the simplicity of the reduced form model and also considers the dynamic evolution of the counterparty assets price by incorporating with the structural model for default risk measurement. We divide the swap pricing framework into two parts, simplifying the pricing model relatively. Simulation results show that, for a one year interest rate swap, a bond spread of one hundred basis points implies a swap credit spread about 0.1054 basis point.

关键词： swap pricing default gamma variance bilateral Brownian assets assumption implies

An Analysis of Two Variational Models for Speckle Reduction of Ultrasound Images

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Acta Mathematicae Applicatae Sinica 2016年第4期32卷 969-982页

作者： Zheng-meng jin Xiao-ping YANG School of Science Nanjing University of Posts and Telecommunications School of Science Nanjing University of Science and Technology

In this paper, we consider two variational models for speckle reduction of ultrasound images. By employing the F-convergence argument we show that the solution of the SO model coincides with the minimizer of the JY model. Furthermore, we incorporate the split Bregman technique to propose a fast alterative algorithm to solve the JY model. Some numericalexperiments are presented to illustrate the efficiency of the proposed algorithm.

关键词： BV F-convergence equivalence multiplicative noise Split Bregman algorithm

Spatial-temporal Divergence Characteristics and Driving Factors of Green Economic Efficiency in the Yangtze River Economic Belt of China

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Chinese Geographical Science 2024年第6期34卷 1158-1174页

作者： PAN Ting jin Gui zeng Shibo WANG Rui China University of Geosciences(Wuhan) Wuhan 430000China

The spatial and temporal variation of green economic efficiency and its driving factors are of great significance for the construction of high-efficiency and low-consumption green development model and sustainable socio-economic *** research focused on the Yangtze River Economic Belt(YREB)and employed the miniumum distance to strong efficient frontier DEA(MinDs)model to measure the green economic efficiency of the municipalities in the region between 2008 and ***,the spatial autocorrelation model was used to analyze the evolution characteristics of its spatial ***,Geodetector was applied to reveal the drivers and their interactions on green economic *** is found that:1)the overall green economic efficiency of the YREB from 2008 to 2020 shows a W-shaped fluctuating upward trend,green economic efficiency is greater in the downstream and smallest in the upstream;2)the spatial distribution of green economic efficiency shows clustering characteristics,with multi-core clustering based on‘city clusters-central cities'becoming more obvious over time;the High-High agglomeration type is mainly clustered in Jiangsu and Zheji-ang,while the Low-Low agglomeration type is clustered in the western Sichuan Plateau area and southwestern Yunnan;3)from input-output factors,whether it is the YREB as a whole or the upper,middle and lower reaches regions,the economic development level,labor input,and capital investment are the leading factors in the spatial-temporal evolution of green economic efficiency,with the com-prehensive influence of economic development level and pollution index being the most important interactive driving factor;4)from so-cio-economic factors,information technology drivers such as government intervention,transportation accessibility,information infra-structure,and Internet penetration are always high impact influencers and dominant interaction factors for green economic efficiency in the YREB and the three major regions in

关键词： green economic efficiency miniumum distance to strong efficient frontier DEA(MinDs) spatial-temporal evolution Geo-detector Yangtze River Economic Belt(YREB),China