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Discussions on Orthogonal Factorizations in Digraphs

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 417-425页

作者： Si-zhong ZHOU hong-xia LIU School of Science Jiangsu University of Science and TechnologyZhenjiang 212100China School of Mathematics and Information Sciences Yantai UniversityYantai 264005China

Let m,t,r and k_(i)(1≤i≤m)be positive integers with k_(i)≥(t+3)r/2,and G be a digraph with vertex set V(G)and arc set E(G).Let H_(1),H_(2),…,H_(t) be t vertex-disjoint subdigraphs of G with mr *** this article,it is verified that every[0,k_(1)+k_(2)+…+k_(m)-(m-1)r]-digraph G has a[0,k_(i)]_(1)^(m)-factorization r-orthogonal to every H_(i) for 1≤i≤t.

关键词： network digraph factor factorization orthogonal factorization

A Minimum Approximate-BER Beamforming Approach for PSK Modulated Wireless Systems

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International Journal of Automation and computing 2008年第3期5卷 284-289页

作者： xia hong Sheng Chen School of Systems Engineering University of Reading Reading RG6 6AY UK School of Electronics and Computer Science University of Southampton Southampton SO17 1BJ UK

A bearnforming algorithm is introduced based on the general objective function that approximates the bit error rate for the wireless systems with binary phase shift keying and quadrature phase shift keying modulation schemes. The proposed minimum approximate bit error rate （ABER） beamforming approach does not rely on the Gaussian assumption of the channel noise. Therefore, this approach is also applicable when the channel noise is non-Gaussian. The simulation results show that the proposed minimum ABER solution improves the standard minimum mean squares error beamforming solution, in terms of a smaller achievable system＇s bit error rate.

关键词： Adaptive beamforming bit error rate gradient descent smart antenna.

Combined Molecular Dynamics Simulation and Rouse Model Analysis of Static and Dynamic Properties of Unentangled Polymer Melts with Different Chain Architectures

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Chinese Journal of Polymer Science 2021年第4期39卷 512-524,I0008页

作者： Pu Yao Lu-Kun Feng hong-xia Guo Beijing National Laboratory for Molecular Sciences Joint Laboratory of Polymer Sciences and MaterialsState Key Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Chain architecture effect on static and dynamic properties of unentangled polymers is explored by molecular dynamics simulation and Rouse mode analysis based on graph *** open chains,although they generally obey ideal scaling in chain dimensions,local structure exhibits nonideal behavior due to the incomplete excluded volume(EV)screening,the reduced mean square internal distance(MSID)can be well described by Wittmer'theory for linear chains and the resulting chain swelling is architecture dependent,i.e.,the more branches a bit stronger *** rings,unlike open chains they are compact in term of global *** to EV effect and nonconcatenated constraints their local structure exhibits a quite different non-Gaussian behavior from open chains,i.e.,reduced MSID curves do not collapse to a single master curve and fail to converge to a chain-length-independent constant,which makes the direct application of Wittmer's theory to rings quite *** from ideality is further evidenced by limited applicability of Rouse prediction to mode amplitude and relaxation time at high modes as well as the non-constant and mode-dependent scaled Rouse mode amplitudes,while the latter is architecture-dependent and even molecular weight dependent for *** chain relaxation time is architecture-dependent,but the same scaling dependence on chain dimensions does hold for all studied *** mode orthogonality at static state,the role of cross-correlation in orientation relaxation increases with time and the time-dependent coupling parameter rises faster for rings than open chains even at short time scales it is lower for rings.

关键词： Rouse model Unentangled chains Architecture Excluded volume effects

High-Order Hamilton's Principle and the Hamilton's Principle of High-Order Lagrangian Function

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Communications in Theoretical Physics 2008年第2期49卷 297-302页

作者： ZHAO hong-xia MA Shan-Jun College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China

In this paper, based on the theorem of the high-order velocity energy, integration and variation principle, the high-order Hamilton＇s principle of general holonomic systems is given. Then, three-order Lagrangian equations and four-order Lagrangian equations are obtained from the high-order Hamilton＇s principle. Finally, the Hamilton＇s principle of high-order Lagrangian function is given.

关键词： Hamilton's principle high-order velocity energy integration and variation principle Lagrangian function

The Global Convergence of Self-Scaling BFGS Algorithm with Nonmonotone Line Search for Unconstrained Nonconvex Optimization Problems

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Acta Mathematica Sinica,English Series 2007年第7期23卷 1233-1240页

作者： hong xia YIN Dong Lei DU Chinese Academy of Sciences Research Center on Data Technology and Knowledge Economy Department of Mathematics Graduate University of the Chinese Academy of Sciences Faculty of Administration University of New Brunswick

The self-scaling quasi-Newton method solves an unconstrained optimization problem by scaling the Hessian approximation matrix before it is updated at each iteration to avoid the possible large eigenvalues in the Hessian approximation matrices of the objective function. It has been proved in the literature that this method has the global and superlinear convergence when the objective function is convex （or even uniformly convex）. We propose to solve unconstrained nonconvex optimization problems by a self-scaling BFGS algorithm with nonmonotone linear search. Nonmonotone line search has been recognized in numerical practices as a competitive approach for solving large-scale nonlinear problems. We consider two different nonmonotone line search forms and study the global convergence of these nonmonotone self-scale BFGS algorithms. We prove that, under some weaker condition than that in the literature, both forms of the self-scaling BFGS algorithm are globally convergent for unconstrained nonconvex optimization problems.

关键词： nonmonotone line search self-scaling BFGS method global convergence

Composite solitons in SU(3) spin–orbit-coupling Bose gases

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Communications in Theoretical Physics 2020年第2期72卷 88-92页

作者： hong-xia Yue Yong-Kai Liu College of Physics and Information Engineering Shanxi Normal UniversityLinfen 041000China

We study solitons in a spin-1 Bose–Einstein condensates with SU(3)spin–orbit *** obtain the ground state and the metastable solution for solitons with attractive interactions by the imaginary-time evolution *** with the SU(2)spin–orbit coupling,it is found that the solitons in SU(3)spin–orbit coupling show a new feature due to breaking the *** solitons called the composite solitons have mixing manifolds of ferromagnetic and antiferromagnetic *** has stimulated people to study the topological excitation properties of SU(3)spin–orbit coupling and it is expected to find new quantum phases.

关键词： composite solitons Bose–Einstein condensates SU(3)spin–orbit-coupling

Global Weak Entropy Solution of Nonlinear Ideal Reaction Chromatography System and Applications

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Acta Mathematicae Applicatae Sinica 2023年第1期39卷 109-134页

作者： Jing ZHANG hong-xia LIU Tao PAN School of Computer Science and Technology Dongguan University of TechnologyDongguan 523808China Department of Mathematics Jinan UniversityGuangzhou 510632China Department of Optoelectronic Engineering Jinan UniversityGuangzhou 510632China

The ideal reaction chromatography model can be regarded as a semi-coupled system of two hyperbolic partial differential equations, in which, one is a self-closed nonlinear equation for the reactant concentration and another is a linear equation coupling the reactant concentration for the resultant concentration. This paper is concerned with the initial-boundary value problem for the above model. By the characteristic method and the truncation method, we construct the global weak entropy solution of this initial initial-boundary value problem for Riemann type of initial-boundary data. Moreover, as examples, we apply the obtained results to the cases of head-on and wide pulse injections and give the expression of the global weak entropy solution.

关键词： ideal reaction chromatography model reactant and resultant concentration initial-boundary value problem global weak entropy solution head-on injection wide pulse injection

Analysis of Off-State Leakage Current Characteristics and Mechanisms of Nanoscale MOSFETs with a High-k Gate Dielectric

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Chinese Physics Letters 2012年第12期29卷 181-184页

作者： LIU hong-xia MA Fei Key Laboratory of Wide Bandgap Semiconductor Materials and Devices of Ministry of Education Xidian UniversityXi'an 710071

The off-state leakage current characteristics of nanoscale channel metal-oxide-semiconductor field-effect transistors with a high-k gate dielectric are thoroughly *** off-state leakage current can be divided into three components:the gate leakage current,the source leakage current,and the substrate leakage *** influences of the fringing-induced barrier lowering effect and the drain-induced barrier lowering effect on each component are investigated *** nanoscale devices with high-k gates,the source leakage current becomes the major component of the off-state leakage current.

关键词： MOSFETs barrier component

Modeling, Experimental Study on the Heat Transfer Characteristics of Thermoelectric Generator

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Journal of Thermal Science 2013年第1期22卷 48-54页

作者： Ze-Guang Zhou Dong-Sheng Zhu hong-xia Wu hong-Sheng Zhang School of Chemistry and Chemical Engineering South China University of Technology

This paper investigates the heat transfer characteristics of a thermoelectric generator. The influence of heat dissipation intensity to the sub-thermal resistances distribution is experimentally studied. Based on the thermal network analysis and finite time thermodynamics, an analytical model including all thermal resistances (in both thermocouples and external heat exchangers) is developed to predict the performance of the generator. The results show that the computed values of output power agree well with the experimental values. The heat transfer enhancement on the generator cold side greatly reduces the cold side temperature and thermal resistance, and obviously improves the output power. Compare with air natural convection cooling, the main thermal resistance changes from the resistance between the fins and the ambient to the thermal contact resistances between the generator and the heat sink at the conditions of forced convection and water cooling. This study may be guide the optimization of generator structure.

关键词： thermoelectric generator thermal network thermal resistance analytical model heat transfercharacteristic output power