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Chinese Journal of Structural Chemistry 2016年第2期35卷 319-325页

作者： LU jiu-Fu shi Juan ZHENG Nan GUO Xiao-Hua GE Hong-Guang Chemical Engineering College Shaanxi University of Technology

A new coordination polymer,{[Ag2（bpp）2（H2O）2]·bpdc·3H2O}n,derived from the ligand biphenyl-4,4＇-dicarboxylic acid（H2bpdc）,has been obtained through a hydrothermal technique（bpp = l,3-bis（4-pyridyl）propane）.Its single-crystal structure has been characterized by single-crystal X-ray diffraction,powder XRD,FT-IR,TGA and elemental analysis *** single-crystal X-ray diffraction reveals that complex 1 consists of 1D infinite[Ag（bpp）（H2O）]n^（n＋）cationic chains,2D anionic layer constructed by bpdc anions and free water which provide charge compensation in the crystal *** 1D infinite[Ag（bpp）（H2O）]n^（n＋） cationic chains and 2D anionic layer are further stacked in-ABAB- fashion through intermolecular H-bonding to form a 3D sandwich-like *** addition,the luminescent property of complex 1 in the solid state at room temperature was investigated.

关键词： Ag(Ι) coordination polymer crystal structure luminescent property

Exact Jacobian Elliptic Function Solutions to sinh-Gordon Equation

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Communications in Theoretical Physics 2006年第1期45卷 55-60页

作者： FU Zun-Tao liu shi-Kuo liu shi-Da School of Physics Peking University Beijing 100871 China State Key Laboratory for Turbulence and Complex Systems Peking University Beijing 100871 China

In this paper, two transformations are introduced to solve sinh-Gordon equation by using the knowledge of elliptic equation and Jacobian elliptic functions. It is shown that different transformations are required in o... 详细信息

关键词： Jacobian elliptic function transformation sinh-Gordon equation

钢框架梁柱节点在强震作用下的损伤性能研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第11期18卷 910-926页

作者： Xi-yue liu Yuan-qing WANG Jun XIONG Yong-jiu shi College of Basic Education for Commanding Officers National University of Defense Technology Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry Department of Civil EngineeringTsinghua University Nanjing Jianye District Bureau of Construction and Transport

目的:钢框架焊接梁柱节点在地震作用下往往容易产生脆性裂纹,裂纹的发展和损伤累积将导致节点延性降低,发生脆性断裂。本文旨在探究节点在地震往复荷载作用下的损伤性能,分析其主要影响因素,提出有效的损伤评估模型,为后续节点损伤数值... 详细信息

目的:钢框架焊接梁柱节点在地震作用下往往容易产生脆性裂纹,裂纹的发展和损伤累积将导致节点延性降低,发生脆性断裂。本文旨在探究节点在地震往复荷载作用下的损伤性能,分析其主要影响因素,提出有效的损伤评估模型,为后续节点损伤数值模拟提供基础,为钢框架的抗震设计提供参考。创新点:1.通过足尺节点试验,分析加载幅值、加载历程和荷载峰值对节点损伤性能的影响;2.基于试验结果,标定并验证3种经验损伤演化模型,提出基于疲劳断裂力学的节点损伤评估模型。方法:1.通过对9个足尺梁柱节点试件开展往复加载试验,包括5种变幅加载制度及4种常幅加载制度,分析加载幅值、加载历程和荷载峰值对节点损伤性能的影响;2.基于试验结果,根据节点损伤特点,在能量模型基础上,推导并拟合适用于节点循环加载的双参数损伤演化方程,并与其他模型进行比较,以验证其准确性;3.结合疲劳和延性断裂理论,依据损伤机理,定义"有效塑性应变"量化损伤过程,并以疲劳裂纹发展公式为基础,推导适用于计算在极低周循环荷载下节点损伤过程的损伤演化方程。结论:1.加载跨幅对节点性能影响较小;加载历程的影响与历程中峰值位移循环次数密切相关;突发性的强峰值对节点造成的损伤最大。2.节点损伤过程为幂函数形式;通过比较表明,在能量模型基础上推导出的适用于节点循环加载的双参数损伤演化方程,相对于单参数线性模型,能够更准确模拟节点在极低周循环下的损伤过程。3.基于疲劳断裂力学理论的损伤演化方程物理意义明确,能够描述节点循环损伤试验中所表现出的加速损伤及"损伤拐点"特征。

关键词：梁柱节点往复荷载节点试验损伤机理延性断裂

Robust Stability of a Class of Fractional Order Hopfield Neural Networks

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Journal of Electronic Science and Technology 2015年第2期13卷 153-157页

作者： Xiao-Lei liu Ming-jiu Gai Cui-Ling Ma Xiao-Yan liu Institute of System Science and Mathematics Naval Aeronautical and Astronautical University

As the theory of the fractional order differential equation becomes mature gradually, the fractional order neural networks become a new *** robust stability of a class of fractional order Hopfield neural network with the Caputo derivative is investigated in this paper. The sufficient conditions to guarantee the robust stability of the fractional order Hopfield neural networks are derived by making use of the property of the Mittag-Leffler function, comparison theorem for the fractional order system, and method of the Laplace integral transform. Furthermore, a numerical simulation example is given to illustrate the correctness and effectiveness of our results.

关键词： fractional Laplace guarantee hotspot mature derivative illustrate Liouville correctness asymptotic

Super-strong interactions between multivalent anions and graphene

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Chinese Physics B 2021年第4期30卷 425-431页

作者： Xing liu Guosheng shi Shanghai Applied Radiation Institute State Key Laboratory Advanced Special SteelShanghai UniversityShanghai 200444China Division of Interfacial Water and Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China

Based on the density functional theory(DFT) calculations,we showed that the interactions between different valence anions(PO_(4)^(3-),CH_(3)PO_(4)^(2-),(CH_(3))_(2)PO_(4)^(-)) and graphene significantly increased as the valence of anion increased from negative monovalence to negative *** adsorption energy of(CH_(3))_(2)PO_(4)^(-)on the electron-rich graphene flake(C84H24)is-8.3 kcal/*** adsorption energy of CH_(3)PO_(4)^(2-) on the electron-rich graphene flake(C_(84)H_(24)) is-48.0 kcal/mol,which is about six times that of(CH_(3))_(2)PO_(4) adsorption on electron-rich graphene flake(C_(84)H_(24)) and is even much larger than that of CO_(3)^(2-) adsorption on electron-deficient aromatic ring C_(6)F_(6)(-28.4 kcal/mol).The adsorption energy of PO_(4)^(3-)on the electron-rich graphene flake(C_(84)H_(24)) is-159.2 kcal/mol,which is about 20 times that of(CH_(3))_(2)PO_(4) adsorption on the graphene flake(C_(84)H_(24)).The super-strong adsorption energy is mainly attributed to the orbital interactions between multivalent anions and *** work provides new insights for understanding the interaction between multivalent anions and π-electron-rich carbon-based nanomaterials and is helpful for the design of graphene-based DNA biosensor.

关键词： graphene multivalent anions anion-πinteraction density functional theory

ISAR autofocus imaging algorithm for maneuvering targets based on deep learning and keystone transform

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1178-1185页

作者： shi Hongyin liu Yue GUO Jianwen liu Mingxin School of Information Science and Engineering Yanshan UniversityQinhuangdao 066004China

The issue of small-angle maneuvering targets inverse synthetic aperture radar(ISAR)imaging has been successfully addressed by popular motion compensation ***,when the target’s rotational velocity is sufficiently high during the dwell time of the radar,such compensation algorithms cannot obtain a high quality *** paper proposes an ISAR imaging algorithm based on keystone transform and deep learning *** keystone transform is used to coarsely compensate for the target’s rotational motion and translational motion,and the deep learning algorithm is used to achieve a super-resolution *** uniformly distributed point target data are used as the data set of the training u-net *** addition,this method does not require estimating the motion parameters of the target,which simplifies the algorithm ***,several experiments are performed to demonstrate the effectiveness of the proposed algorithm.

关键词： inverse synthetic aperture radar(ISAR) maneuvering target keystone transform deep learning u-net network

Envelope Periodic Solutions to Bose-Einstein Condensation in Linear Magnetic Field and Time-Dependent Laser Field

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Communications in Theoretical Physics 2009年第7期52卷 88-90页

作者： GAO Bin liu shi-Kuo liu shi-Da School of Physics Peking University Beijing 100871 China Department of Physics Yuxi Normal University Yuxi 653100 China

In this paper, by applying the extended 3acobi elliptic function expansion method, the envelope periodic solutions and corresponding dark soliton solution, bright soliton solution to Bose-Einstein condensation in line... 详细信息

关键词： Bose-Einstein condensation Jacobi elliptic function envelope periodic solution soliton solution

Trial Equation Method to Nonlinear Evolution Equations with Rank Inhomogeneous： Mathematical Discussions and Its Applications

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Communications in Theoretical Physics 2006年第2期45卷 219-223页

作者： liu Cheng-shi Department of Mathematics Daqing Petroleum Institute Daqing 163318 China

A trial equation method to nonlinear evolution equation with rank inhomogeneous is given. As appncations, the exact traveling wave solutions to some higher-order nonlinear equations such as generalized Boussinesq equation, generalized Pochhammer-Chree equation, KdV-Burgers equation, and KS equation and so on, are obtained. Among these, some results are new. The proposed method is based on the idea of reduction of the order of ODE. Some mathematical details of the proposed method are discussed.

关键词： trial equation method solvable equation nonlinear evolution equation exact solution

New Exact Envelope Traveling Wave Solutions of High-Order Dispersive Cubic-Quintic Nonlinear SchrSdinger Equation

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Communications in Theoretical Physics 2005年第5X期44卷 799-801页

作者： liu Cheng-shi Department of Mathematics Daqing Petroleum Institute Daqing 163318 China

Using trial equation method, abundant exact envelope traveling wave solutions of high-order dispersive cubic-quintic nonlinear Schr6dinger equation, which include envelope soliton solutions, triangular function envelope solutions, and Jacobian elliptic function envelope solutions, are obtained. To our knowledge, all of these results are new. In particular, our proposed method is very simple and can be applied to a lot of similar equations.

关键词： trial equation method exact solution nonlinear Schrodinger equation

Variational method based robust adaptive control for a guided spinning rocket

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Chinese Journal of Aeronautics 2021年第3期34卷 164-175页

作者： Zhongjiao shi Liangyu Zhao Zhijie liu School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China

In this paper,a robust adaptive controller is designed for a guided spinning rocket,whose dynamics presents the characteristics of pitch-yaw cross coupling,fast time-varying aerodynamics parameters and wide flight ***,a coupled nonlinear six-degree-of-freedom equation of motion for a guided spinning rocket is developed,and the lateral acceleration motion is modeled as a control plant with time-varying matched uncertainties and unmodeled ***,a robust adaptive control method is proposed by combining Bregman divergence and variational method to achieve fast adaption and maintain bounded *** stability of the resulting closed-loop system is proved,and the ultimate bound and convergence rate are also ***,numerical simulations are performed for a single operating point and the whole flight trajectory to show the robustness and adaptability of the proposed method with respect to timevarying uncertainties and unmodeled dynamics.

关键词： Autopilot design Guided spinning rockets Robust adaptive control Second-order adaptive law Variational method