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1D Ferromagnetic Interaction of 2-Iodo Nitronyl Nitroxide Radical Confirmed by Spin Density Calculation

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Chemical Research in Chinese Universities 2012年第6期28卷 1066-1069页

作者： LIU Zhi-liang SONG ye DU Chun-fang College of Chemistry and Chemical Engineering Inner Mongolia University Hohhot 010021 P. R. China

A supramolecular 1D ferromagnetic system was studied experimentally as well as *** density functional theory（DFT） calculations were based on the X-ray *** results of DFT calculations and McConnell mechanism have contributed to the understanding of the factors governing the exchange coupling of magnetism in the crystal *** the experimental evidence and theoretical calculation indicate that spin density in 2-iodo nitronyl nitroxide（INN） radicals confirms 1D ferromagnetic chain with inter-chain antiferromagnetic interaction.

关键词： Supramolecular chemistry Density functional theory calculation Spin density Ferromagnetic chain

Integration of a Nonlinear Vibration Absorber and Levitation Magnetoelectric Energy Harvester for Whole-Spacecraft Systems

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Acta Mechanica Solida Sinica 2019年第3期32卷 298-309页

作者： ye-Wei Zhang Zhi-Wei fang Shi-Lei Wang Zhi-Yu Ni Jian Zang Bo fang College of Aerospace Engineering Shenyang Aerospace University Shenyang 110136 China Shanghai Prime Machinery Company Limited Shanghai 200072 China

This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger energy harvesting capability than the existing systems. It harvests energy from a wide frequency range and has a high output voltage. The harvested energy is determined by magnetic field strength, excitation frequency, and resistive load. The change in the magnetic field strength has the least impact on the output voltage. The vibration reduction effects and harvested energy of the system are analyzed with an approximate analytical method that combines the harmonic balance approach and the pseudo-arclength continuation algorithm. The results of the Runge-Kutta method are nearly consistent with those of the approximate analytical method. Moreover, the effects of the excitation frequency, resistive load, and parameters of the nonlinear energy sink on the system vibration response and energy harvesting are analyzed.

关键词： Levitation magnetoelectric energy harvester Whole spacecraft Nonlinear energy sink Vibration reduction

2-ORDER TURBULENCE CLOSURE PLANKTON ECOSYSTEM DYNAMICS MODEL AND ITS APPLICATION

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Journal of Hydrodynamics 2001年第3期13卷 17-23页

作者： Wan, Zhen-Wen Yuan, ye-Li Qiao, fang-Li State Oceanic Administration Qingdao 266003 China

The basic concepts of continuous neurogen dynamics, particle and continuous mass, were cited to describe plankton ecosystems, so a continuous neurogen dynamics model of plankton ecosystem was developed by logically reasoning with less ecological experiential relation. For precise parameterization of diffusion acted on plankton by hydrodynamics, the scheme of 2-order turbulence closure of geophysical fluid dynamics was generalized to enclose the equations of plankon ecosystem dynamics model. This model was applied to simulate a natural ecological process in Jiaozhou Bay. Comparison between simulation and data showed the exciting prognosis ability of this model.

关键词： Ecosystems Mathematical operators Numerical analysis Simulation Turbulence

Mesh parameterization based on edge collapse

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1153-1159页

作者： Jiang QIAN Xiu-zi ye Cui-hao fang San-yuan ZHANG State Key Lab of CAD & CG School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

Parameterizations that use mesh simplification to build the base domain always adopt the vertex removal *** paper applies edge collapse to constructing the base domain *** inducing the parameterization of the original mesh over the base domain,new algorithms map the new vertices in the simplified mesh back to the original one according to the edge transition sequence to integrate the *** present a direct way,namely edge classification,to deduce the *** results show that the new parameterization features considerable saving in computing complexity and maintains smoothness.

关键词： Edge collapse Vertex removal Mapping Edge classification

A BRANCH-AND-CUT APPROACH TO PORTFOLIO SELECTION WITH MARGINAL RISK CONTROL IN A LINEAR CONIC PROGRAMMING FRAMEWORK

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Journal of Systems Science and Systems Engineering 2013年第4期22卷 385-400页

作者： Zhibin DENG Yanqin BAI Shu-Cherng fang ye TIAN Wenxun XING School of Management University of Chinese Academy of Sciences Industrial and Systems Engineering Department North Carolina State University Department of Mathematics Shanghai University School of Business Administration Southwestern University of Finance and Economics Department of Mathematical Sciences Tsinghua University

Marginal risk represents the risk contribution of an individual asset to the risk of the entire portfolio In this paper, we investigate the portfolio selection problem with direct marginal risk control in a linear conic programming framework. ＇The optimization model involved is a nonconvex quadratically constrained quadratic programming （QCQP） problem. We first transform the QCQP problem into a linear conic programming problem, and then approximate the problem by semidefinite programming （SDP） relaxation problems over some subrectangles. In order to improve the lower bounds obtained from the SDP relaxation problems, linear and quadratic polar cuts are introduced for designing a branch-and-cut algorithm, that may yield an e -optimal global solution （with respect to feasibility and optimality） in a finite number of iterations. By exploring the special structure of the SDP relaxation problems, an adaptive branch-and-cut rule is employed to speed up the computation. The proposed algorithm is tested and compared with a known method in the literature for portfolio selection problems with hundreds of assets and tens of marginal risk control constraints.

关键词： Portfolio selection linear conic programming branch-and-cut

Specific Thermoresponsive Behaviours Exhibited by Optically Active and Inactive Phenylalanine Modified Hyperbranched Polyethylenimines in Water

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Chinese Journal of Polymer Science 2017年第8期35卷 1035-1042页

作者： Wu-cheng fang Ran Zhang ye-feng Yao 刘华姬陈宇 Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistrySchool of SciencesTianjin Universityand Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Department of Physics & Shanghai Key Laboratory of Magnetic Resonance East China Normal University

Optically active and inactive hyperbranched polymers with specific thermoresponsive behaviours in water were *** two steps hyperbranched polyethylenimine（HPEI） polymers terminated with different amount of D-phenylalanine（D-Phe）,L-phenylalanine（L-Phe） or DL-phenylalanine（DL-Phe） were prepared and *** analyses on the solution properties by turbidimetry,dynamic light scattering,fluorescence probe and 1H-NMR demonstrated that all the polymers exhibited specific thermoresponsive behaviours in water,including：（1） In the dilute polymer concentration region,increasing the polymer concentration led to the increase of phase transition temperature;（2） The optically inactive thermoresponsive hyperbranched polymers showed a higher cloud-point temperature（Tcp） than their corresponding optically active ones in a relatively higher polymer concentration;（3） At the same polymer concentration the hydrophobic groups of the optically inactive HPEI-DL-Phe formed more perfect hydrophobic domain than those of the optically active HPEI-L-Phe and HPEI-D-Phe.

关键词： optically phenylalanine terminated hydrophobic inactive dilute Modified hydrophilic responsive solubility

AN NMF ALGORITHM FOR BLIND SEPARATION OF CONVOLUTIVE MIXED SOURCE SIGNALS WITH LEAST CORRELATION CONSTRAINS

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Journal of Electronics(China) 2009年第4期26卷 557-563页

作者： Zhang ye fang Yong School of Communication and Information Engineering Shanghai University Shanghai 200072 China Department of Electronic and Information Engineering Nanchang University Nanchang 330031 China

Most of the existing algorithms for blind sources separation have a limitation that sources are statistically independent. However, in many practical applications, the source signals are non- negative and mutual statistically dependent signals. When the observations are nonnegative linear combinations of nonnegative sources, the correlation coefficients of the observations are larger than these of source signals. In this letter, a novel Nonnegative Matrix Factorization (NMF) algorithm with least correlated component constraints to blind separation of convolutive mixed sources is proposed. The algorithm relaxes the source independence assumption and has low-complexity algebraic com- putations. Simulation results on blind source separation including real face image data indicate that the sources can be successfully recovered with the algorithm.

关键词： Nonnegative matrix factorization Convolutive blind source separation Correlation constrain

Exploring the effect of Arctic perennial sea ice on modulation of local air temperature

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Advances in Climate Change Research 2022年第4期13卷 473-488页

作者： Yu-fang ye Mohammed SHOKR Zhuo-Qi CHEN Xiao CHENG School of Geospatial Engineering and Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Science and Technology Branch Environment and Climate Change CanadaToronto M3H5T4Canada

Sea ice cover plays an important role in modulating local temperature through heat and moisture *** infuence of thin ice lead and polynya has been wellinvestigated,however,the effect of perennial ice(also called muliyear ice,MYI)has *** study is motivated by it and investigated a hypothesis that changes in MYI concentration in winter triggers changes in short-term local 2-m air *** hypothesis was tested using time series analysis of the two parameters and correlation between *** from the winters of 2004-2009 were used for the examination at three spatial *** hypothesis is found to be potentially accepted when MYI exists in a consolidated ice regime with negligible thin ice or open water in the surroundings,and the air temperature is low *** for the acceptance of the hypothesis were quantitatively *** qualifications entail that the ice cell must experience daily change of MYI concentration meanwhile satisfy the criteria of total ice concentration(TIC),young ice concentration(YIC)and air temperature(Tar)in the surrounding area,which are TIC>88.3%,YICding changes in air temperature were developed retroactively using data that satisfied the acceptance *** relationships varied with years,depending on ice conditions such as ice type distributions and snow *** study offers a first attempt to assess the effect of MYI on the same-day local surface air temperature using satelite observations,and provides evidence of this effect under quantitatively quanlifying conditions.

关键词： Arctic sea ice Multiyear ice Arctic response to climate change Microwave remote sensing

dielectric and Electromagnetic Wave Absorbing Properties of Two Types of SiC Fibres with different Compositions

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Journal of Materials Science & Technology 2013年第1期29卷 55-58页

作者： fang ye Litong Zhang Xiaowei Yin Yongsheng Liu Laifei Cheng Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical University State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The dielectric and electromagnetic properties of two types of SiC fibres with different compositions were investigated. The permittivity and electromagnetic shielding effectiveness （SE） of SiC fibre bundles were measured in 8.2-12.4 GHz by waveguide method. The reflection coefficient （RC） of unidirectional SiC fibre laminates was determined in 8-18 GHz using naval research laboratory （NRL）-arc method. Results showed that the electromagnetic wave （EMW） absorbing properties of SiC fibres were correlated with their composition, microstructure and instinct performance of electrical resistance. SiC fibres with higher content and greater size of nano-scale H-SiC showed higher permittivity, conductivity, SE and lower RC, which resulted in their better EMW absorbing ability, Le. the lower reflection to EMW.

关键词： SiC fibre dielectric Electrical and magnetic properties