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双壁波纹钢管混凝土构件短柱轴压力学性能

哈尔滨工业大学学报 2025年第1期57卷 56-64页

作者：路博崔燕方勇王玉银李豪哈尔滨工业大学土木工程学院哈尔滨150090 结构工程灾变与控制教育部重点实验室(哈尔滨工业大学) 哈尔滨150090 深圳市市政设计研究院有限公司广东深圳518029

为改善空心钢筋混凝土柱(HRC)的使用与受力性能,提出一种双壁波纹钢管混凝土(CFDCST)构件。本文共进行了4个大尺寸双壁波纹钢管混凝土短柱与2个空心钢筋混凝土短柱的轴压试验,关键试验参数为试件类型与波纹钢管类型。分析构件的破坏模式... 详细信息

为改善空心钢筋混凝土柱(HRC)的使用与受力性能,提出一种双壁波纹钢管混凝土(CFDCST)构件。本文共进行了4个大尺寸双壁波纹钢管混凝土短柱与2个空心钢筋混凝土短柱的轴压试验,关键试验参数为试件类型与波纹钢管类型。分析构件的破坏模式,对比不同参数下构件的承载力、峰值应变、延性系数等关键力学指标,获得荷载-波纹钢管应变关系曲线以揭示试件的约束机理并验证外波纹钢管类型的影响。试验结果表明:外波纹钢管可为夹层混凝土提供约束作用,且螺旋角越小,外波纹钢管的约束作用越强;内波纹钢管则主要为夹层混凝土内壁提供有效支撑,以保持截面的完整性。名义约束效应系数与空心率相近时,由于咬口滑移影响,大螺旋角双壁波纹钢管混凝土比小螺旋角双壁波纹钢管混凝土的峰值应力、峰值应变与延性系数分别降低15.5%、21.8%与16.7%。在总用钢量相近的情况下,小螺旋角双壁波纹钢管混凝土柱的承载力、峰值应变与延性系数分别比空心钢筋混凝土柱提高10.6%、36.2%与50.0%。基于试验结果,检验了3种典型承载力公式的适用性,并提出了相应设计建议。

关键词：组合结构空心钢筋混凝土波纹钢管双壁构件约束机理

Two-Dimensional DOA Estimation Using One-Dimensional Search for Spherical Arrays

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Chinese Journal of Electronics 2019年第6期28卷 1259-1264页

作者： HUANG Qinghua FENG Jiajun fang yong Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University

A Reduced-dimensional spherical harmonics MUSIC(RD-SHMUSIC) is proposed to solve the problem of high computational complexity of Multiple signal classification(MUSIC) algorithm for Twodimensional(2-D) Direction of arrival(DOA) *** proposed algorithm first expresses the spherical harmonic steering vector as a linear weight of a uniform phase vectors. Via the Lagrange multiplier method, we can get a new search function to estimate elevations. At second step, the algorithm expresses the steering vector in another form, a linear weight of a vector which is constructed by associated Legendre functions. A search function to estimate azimuths can also be *** proposed method only needs One dimensional(1-D) angle search, which means it has a large reduction of computational complexity compared to the traditional Spherical harmonics MUSIC(SHMUSIC). The simulation results show that the accuracy of the proposed method is better than Two-stage decoupled approach(TSDA)algorithm, and has close performance to that of SHMUSIC.

关键词： Direction of arrival estimation Spherical arrays Reduced-dimensional spherical harmonics MUSIC Computational complexity

Equilibria and Stability Analysis of Cohen-Grossberg BAM Neural Networks on Time Scale

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Journal of Systems Science & Complexity 2022年第4期35卷 1348-1373页

作者： LIU Mingshuo fang yong DONG Huanhe College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao266590China

This paper considers the Cohen-Grossberg BAM neural networks(CG-BAMNNs) on time scale, which can unify and generalize the continuous and discrete systems. First, the criteria for the existence and uniqueness of the equilibrium of CG-BAMNNs are derived on time scale. Then based on that, the authors give the criteria for the stability and estimation of equilibrium of the CG-BAMNNs on time scale. The method proposed in this paper unifies and generalizes the continuous and discrete CGBAMNNs systems, and is applicable to some other neural network systems on time scale with practical meaning. The effectiveness of the proposed criteria for delayed CG-BAMNNs is demonstrated by numerical simulation.

关键词： Cohen-Grossberg BAM neural networks existence numerical simulation stability uniqueness

A New Method for Solving Nonlinear Partial Differential Equations Based on Liquid Time-Constant Networks

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Journal of Systems Science & Complexity 2024年第2期37卷 480-493页

作者： SUN Jiuyun DONG Huanhe fang yong College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this paper,physics-informed liquid networks(PILNs)are proposed based on liquid time-constant networks(LTC)for solving nonlinear partial differential equations(PDEs).In this approach,the network state is controlled via ordinary differential equations(ODEs).The significant advantage is that neurons controlled by ODEs are more expressive compared to simple activation *** addition,the PILNs use difference schemes instead of automatic differentiation to construct the residuals of PDEs,which avoid information loss in the neighborhood of sampling *** this method draws on both the traveling wave method and physics-informed neural networks(PINNs),it has a better physical ***,the KdV equation and the nonlinear Schr¨odinger equation are solved to test the generalization ability of the *** the best of the authors’knowledge,this is the first deep learning method that uses ODEs to simulate the numerical solutions of PDEs.

关键词： Nonlinear partial differential equations numerical solutions physics-informed liquid networks physics-informed neural networks

Compressed sensing based channel estimation for fast fading OFDM systems

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Journal of Systems Engineering and Electronics 2010年第4期21卷 550-556页

作者： Xiaoping Zhou yong fang Min Wang Key Laboratory of Specialty Fiber Optics and Optical Access Networks School of Communication and Information Engineering Shanghai University Shanghai 200072 P. R. China Key Laboratory of Advanced Display and System Applications Shanghai 200072 P. R. China

A compressed sensing（CS） based channel estimation algorithm is proposed by using the delay-Doppler sparsity of the fast fading channel.A compressive basis expansion channel model with sparsity in both time and frequency domains is *** pilots in accordance with a novel random pilot matrix in both time and frequency domains are sent to measure the delay-Doppler sparsity *** relatively nonzero channel coefficients are tracked by random pilots at a sampling rate significantly below the Nyquist *** sparsity channels are estimated from a very limited number of channel measurements by the basis pursuit *** proposed algorithm can effectively improve the channel estimation performance when the number of pilot symbols is reduced with improvement of throughput efficiency.

关键词： compressed sensing sparse channel channel estimation fast fading.

Hybrid transmit antenna selection and maximal-ratio transmission systems

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Journal of Systems Engineering and Electronics 2007年第2期18卷 229-235页

作者： Zhu Yaolin fang yong Wang Min School of Communication and Information Engineering Shanghai Univ. Shanghai 200072P.R.China

Maximal-ratio transmission systems with transmit antenna selection is investigated. According to the order statistics of channel fiat fading coefficients, the closed-form expressions axe derived for average SNR with any amount of RF chains and average BER with two RF chains, respectively. The algorithm for calculating the minimum of total transmit antennas is presented in terms of reduced RF chains. The method of quantizing transmit precoders is employed in this study to decrease feedback information. Simulation results demonstrate the superiority of the proposed systems under full and quantized transmit precoders. The SNR of the proposed systems has been less degraded by the quantization of transmit precoder than that of pure maximal-ratio transmission systems.

关键词： Maximal-ratio transmission transmit antenna selection Lloyd quantization.

New chaos M-ary modulation method and its application in communications

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 77-83页

作者： FU yong-qing ZHANG fang College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China

At present, chaotic communications have been widely studied. However, these researches mainly focus on the binary systems while the researches of M-ary chaotic communications are not extensive. To change the situation, a chaos M-ary modulation method based on phase plane partition of Hamilton map is proposed. Firstly, the chaotic model of Hamilton map and its phase plane features are described, and then the way of creating the chaos M-ary modulation is discussed. Next, to evaluate the proposed method, the system simulation results and analysis are given. Finally, the chaos M-ary modulation method is applied to communications.

关键词： chaos M-ary modulation Hamilton map initial value mapping method phase plane partition

Experimental Observation of Constructive Quantum Interference via Hybrid Excitation in an Na2-Na System

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Chinese Physics Letters 2002年第3期19卷 334-337页

作者： Yang Xi-Hua, Li yong-fang Key Laboratory of Optical and Magnetic Resonance Spectroscopy Department of Physics East China Normal University Department of Physics Xi"an JiaoTong University Department of Physics Shaanxi Normal University

We report on an experimental observation of constructive quantum interference between two atomic transition pathways 3P1/2-5S (or 4D) and 3P3/2-5S (or 4D) via equal-frequency hybrid excitation and collision-aided radiative excitation in an Na2-Na system. Through the special excitation processes, constructive quantum interference is realized for a Λ-type quantum-beat configuration with a widely-spaced doublet (about 17 cm^-1) in the excited sodium atom driven by one laser. The dependences of quantum interference on the argon buffer gas pressure and sample temperature are also examined.

关键词： Excited states

Time-fractional Davey–Stewartson equation:Lie point symmetries,similarity reductions,conservation laws and traveling wave solutions

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Communications in Theoretical Physics 2023年第10期75卷 10-25页

作者： Baoyong Guo yong fang Huanhe Dong College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao266590China

As a celebrated nonlinear water wave equation,the Davey–Stewartson equation is widely studied by researchers,especially in the field of mathematical *** the basis of the Riemann–Liouville fractional derivative,the time-fractional Davey–Stewartson equation is investigated in this *** application of the Lie symmetry analysis approach,the Lie point symmetries and symmetry groups are *** the same time,the similarity reductions are ***,the equation is converted to a system of fractional partial differential equations and a system of fractional ordinary differential equations in the sense of Riemann–Liouville fractional *** virtue of the symmetry corresponding to the scalar transformation,the equation is converted to a system of fractional ordinary differential equations in the sense of Erdélyi–Kober fractional integro-differential *** using Noether’s theorem and Ibragimov’s new conservation theorem,the conserved vectors and the conservation laws are ***,the traveling wave solutions are achieved and plotted.

关键词： time-fractional Davey–Stewartson equation Lie symmetry analysis approach Lie point symmetries similarity reductions conservation laws