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Low-frequency vibration suppression of meta-beam with softening nonlinearity
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作者 Weixing ZHANG Dongshuo YANG Xiangying GUO 《Applied Mathematics and Mechanics(English Edition)》 2025年第6期1011-1028,共18页
In order to obtain a lower frequency band gap,this paper proposes a novel locally resonant meta-beam incorporating a softening nonlinear factor.An improved camroller structure is designed in this meta-beam to achieve ... In order to obtain a lower frequency band gap,this paper proposes a novel locally resonant meta-beam incorporating a softening nonlinear factor.An improved camroller structure is designed in this meta-beam to achieve the softening nonlinear stiffness of the local oscillators.Firstly,based on Hamilton's principle and the Galerkin method,the control equations for the coupled system are established.The theoretical band gap boundary is then derived with the modal analysis method.The theoretical results reveal that the band gap of the meta-beam shifts towards lower frequencies due to the presence of a softening nonlinear factor,distinguishing it from both linear metamaterials and those with hardening nonlinear characteristics.Then,the vibration attenuation characteristics of a finite size meta-beam are investigated through numerical calculation,and are verified by the theoretical results.Furthermore,parameter studies indicate that the reasonable design of the local oscillator parameters based on lightweight principles helps to achieve further broadband and efficient vibration reduction in the low-frequency region.Finally,a prototype of the meta-beam is fabricated and assembled,and the formations of the low-frequency band gap and the amplitude-induced band gap phenomenon are verified through experiments. 展开更多
关键词 softening nonlinearity nonlinear band gap meta-beam LOW-FREQUENCY vibration attenuation
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Chirped solutions and dynamical properties of the resonant Schr?dinger equation with quadratic-cubic nonlinearity
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作者 TANG Jia-xuan 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第1期223-237,共15页
In this paper, the nonlinear Schr?dinger equation combining quadratic-cubic nonlinearity is considered, which can be represented by an approximate model of relatively dense quasi-one-dimensional Bose-Einstein condensa... In this paper, the nonlinear Schr?dinger equation combining quadratic-cubic nonlinearity is considered, which can be represented by an approximate model of relatively dense quasi-one-dimensional Bose-Einstein condensate. Based on the bifurcation theory, we proved the existence of solitary and periodic solutions. The methods we take are the trial equation method and the complete discrimination system for polynomial method. Therefore, we obtain the exact chirped solutions, which are more abundant in type and quantity than the existing results, so that the equation has more profound physical significance. These two methods are rigorously mathematical derivation and calculations, rather than based on certain conditional assumptions. In addition, we give some specific parameters to graphing the motion of the solutions, which helps to understand the propagation of nonlinear waves in fiber optic systems. 展开更多
关键词 chirped solutions bifurcation theory trial equation method quadratic-cubic nonlinearity non-linear waves
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Enhancing entanglement and steering in a hybrid atom–optomechanical system via Duffing nonlinearity
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作者 Ling-Hui Dong Xiao-Jie Wu +1 位作者 Cheng-Hua Bai Shao-Xiong Wu 《Chinese Physics B》 2025年第2期124-131,共8页
We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system... We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system comprises an optical cavity, a two-level atomic ensemble and a mechanical resonator that possesses Duffing nonlinearity. The interaction between these components is mediated by the cavity mode, which is driven by an external laser. Our findings indicate that optimizing the coupling strengths between photons and phonons, as well as between atoms and the cavity,leads to maximal entanglement and EPR steering. The amplitude of the driving laser plays a pivotal role in enhancing the coupling between photons and phonons, and the system maintains robust entanglement and EPR steering even under high dissipation, thereby mitigating the constraints on initial conditions and parameter precision. Remarkably, the Duffing nonlinearity enhances the system's resistance to thermal noise, ensuring its stability and entanglement protection. Our analysis of EPR steering conditions reveals that the party with lower dissipation exhibits superior stability and a propensity to steer the party with higher dissipation. These discoveries offer novel perspectives for advancing quantum information processing and communication technologies. 展开更多
关键词 quantum entanglement EPR steering optomechanical system Duffing nonlinearity
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Symmetry of traveling wave solutions for a Camassa–Holm type equation with higher-order nonlinearity
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作者 Wenguang Cheng Ji Lin 《Communications in Theoretical Physics》 2025年第7期14-18,共5页
We are concerned with a Camassa-Holm type equation with higher-order nonlinearity including some integrable peakon models such as the Camassa-Holm equation,the Degasperis-Procesi equation,and the Novikov equation.We s... We are concerned with a Camassa-Holm type equation with higher-order nonlinearity including some integrable peakon models such as the Camassa-Holm equation,the Degasperis-Procesi equation,and the Novikov equation.We show that all the horizontal symmetric waves for this equation must be traveling waves.This extends the previous results for the Camassa-Holm and Novikov equations. 展开更多
关键词 Camassa-Holm type equation with higher-order nonlinearity traveling waves weak solutions
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Effect of Wave Nonlinearity on the Instantaneous Seabed Liquefaction 被引量:1
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作者 WANG Zhao-jun SUI Ti-ti +1 位作者 ZHANG Chi PAN Jun-ning 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期93-103,共11页
The nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal engineers.In this study,an analytical formula considering the nonlin... The nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal engineers.In this study,an analytical formula considering the nonlinear wave skewness and asymmetry is adopted to provide wave pressure on the seabed surface.The liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively characterize the nonlinear effect of wave on seabed liquefaction.Based on the 2D full dynamic model of wave-induced seabed response,a detailed parametric study is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed liquefaction.Further,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear wave.Results indicate that(1)Due to the influence of wave nonlinearity,the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity,the liquefaction depth of seabed decreases gradually.Especially under asymmetric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave conditions.However,highly skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)The asymmetry of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)Compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading. 展开更多
关键词 nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction
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Multiple mixed state variable incremental integration for reconstructing extreme multistability in a novel memristive hyperchaotic jerk system with multiple cubic nonlinearity
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作者 王梦蛟 辜玲芳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期238-246,共9页
Memristor-based chaotic systems with infinite equilibria are interesting because they generate extreme multistability.Their initial state-dependent dynamics can be explained in a reduced-dimension model by converting ... Memristor-based chaotic systems with infinite equilibria are interesting because they generate extreme multistability.Their initial state-dependent dynamics can be explained in a reduced-dimension model by converting the incremental integration of the state variables into system parameters.However,this approach cannot solve memristive systems in the presence of nonlinear terms other than the memristor term.In addition,the converted state variables may suffer from a degree of divergence.To allow simpler mechanistic analysis and physical implementation of extreme multistability phenomena,this paper uses a multiple mixed state variable incremental integration(MMSVII)method,which successfully reconstructs a four-dimensional hyperchaotic jerk system with multiple cubic nonlinearities except for the memristor term in a three-dimensional model using a clever linear state variable mapping that eliminates the divergence of the state variables.Finally,the simulation circuit of the reduced-dimension system is constructed using Multisim simulation software and the simulation results are consistent with the MATLAB numerical simulation results.The results show that the method of MMSVII proposed in this paper is useful for analyzing extreme multistable systems with multiple higher-order nonlinear terms. 展开更多
关键词 extreme multistability HYPERCHAOTIC jerk system nonlinearity
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Influence of Kerr Effect on Second-Order Nonlinearity Induced Transparency
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作者 ZHANG Zhiqiang ZHOU Yanhui 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2024年第1期67-73,共7页
We theoretically study the effect of Kerr effect on the second-order nonlinearity induced transparency in a double-resonant optical cavity system.We show that in the presence of the Kerr effect,as the strength of the ... We theoretically study the effect of Kerr effect on the second-order nonlinearity induced transparency in a double-resonant optical cavity system.We show that in the presence of the Kerr effect,as the strength of the Kerr effect increases,the absorption curve exhibits an asymmetric-symmetric-asymmetric transition,and the zero absorption point shifts with the increase of the Kerr effect.Furthermore,by changing the strength of the Kerr effect,we can control the width of the transparent window,and the position of the zero-absorption point and meanwhile change the left and right width of the absorption peak.The asymmetry absorption curve can be employed to improve the quality factor of the cavity when the frequency detuning is tuned to be around the right peak.The simple dependence of the zeroabsorption point on the strength of Kerr effect suggests that the strength of Kerr effect can be measured by measuring the position of the zero-absorption point in a possible application. 展开更多
关键词 Kerr effect second-order nonlinearity induced transparency nonlinear optics quantum optics
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ASYMPTOTIC BEHAVIOR NEAR THE BOUNDARY OF A LARGE SOLUTION TO SEMILINEAR POISSON EQUATION WITH DOUBLE-POWER NONLINEARITY
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作者 Kazuhiro TAKIMOTO Yuxiao ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第6期2083-2098,共16页
We deal with a large solution to the semilinear Poisson equation with doublepower nonlinearityΔ^(u)=u^(p)+αu^(q)in a bounded smooth domain D■R^(n),where p>1,-1<q<p andα∈R.We obtain the asymptotic behavio... We deal with a large solution to the semilinear Poisson equation with doublepower nonlinearityΔ^(u)=u^(p)+αu^(q)in a bounded smooth domain D■R^(n),where p>1,-1<q<p andα∈R.We obtain the asymptotic behavior of a solution u near the boundary OD up to the third or higher term. 展开更多
关键词 large solution semilinear Poisson equation double-power nonlinearity ASYMPTOTICBEHAVIOR
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Quasi-anti-parity–time-symmetric single-resonator micro-optical gyroscope with Kerr nonlinearity
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作者 耿靖童 徐书逸 +4 位作者 靳婷 丁舒林 杨柳 王颖 张勇刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期436-440,共5页
Parity–time(PT) and quasi-anti-parity–time(quasi-APT) symmetric optical gyroscopes have been proposed recently which enhance Sagnac frequency splitting. However, the operation of gyroscopes at the exceptional point(... Parity–time(PT) and quasi-anti-parity–time(quasi-APT) symmetric optical gyroscopes have been proposed recently which enhance Sagnac frequency splitting. However, the operation of gyroscopes at the exceptional point(EP) is challenging due to strict fabrication requirements and experimental uncertainties. We propose a new quasi-APT-symmetric micro-optical gyroscope which can be operated at the EP by easily shifting the Kerr nonlinearity. A single resonator is used as the core sensitive component of the quasi-APT-symmetric optical gyroscope to reduce the size, overcome the strict structural requirements and detect small rotation rates. Moreover, the proposed scheme also has an easy readout method for the frequency splitting. As a result, the device achieves a frequency splitting 10~5 times higher than that of a classical resonant optical gyroscope with the Earth's rotation. This proposal paves the way for a new and valuable method for the engineering of micro-optical gyroscopes. 展开更多
关键词 optical gyroscopes quasi-anti-parity–time(quasi-APT)symmetric system exceptional point(EP) the Kerr nonlinearity
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Bright soliton dynamics for resonant nonlinear Schrödinger equation with generalized cubic-quintic nonlinearity
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作者 Keyu Bao Xiaogang Tang Ying Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第12期278-288,共11页
For systems modeled by the resonant nonlinear Schrödinger equation(RNLSE)with generalized cubic-quintic nonlinearity,we derive the bright soliton solution of the equation in(1+1)dimensions,using the modified F-ex... For systems modeled by the resonant nonlinear Schrödinger equation(RNLSE)with generalized cubic-quintic nonlinearity,we derive the bright soliton solution of the equation in(1+1)dimensions,using the modified F-expansion method along with the novel ansatz of F-base function.Furthermore,we extend the analytical study of soliton dynamics to higher(2+1)and(3+1)dimensions by using the self-similar method,and demonstrate the soliton behavior via graphical illustration.Moreover,we investigate the effect of the resonance term on bright soliton solution in(1+1)dimensions.Additionally,we consider the nonlinear equation models with perturbation terms and derive the bright soliton solutions for the one-dimensional(1D)to three-dimensional(3D)cases.The theoretical results derived can be used to guide the experimental studies and observations of bright solitons in systems described by RNLSE model. 展开更多
关键词 SOLITON resonant nonlinear Schrödinger equation F-expansion method
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Selective Impact of Dispersion and Nonlinearity on Waves and Solitary Wave in a Strongly Nonlinear and Flattened Waveguide
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作者 Christian Regis Ngouo Tchinda Marcelle Nina Zambo Abou’ou Jean Roger Bogning 《Open Journal of Applied Sciences》 2024年第7期1730-1753,共24页
The waveguide which is at the center of our concerns in this work is a strongly flattened waveguide, that is to say characterized by a strong dispersion and in addition is strongly nonlinear. As this type of waveguide... The waveguide which is at the center of our concerns in this work is a strongly flattened waveguide, that is to say characterized by a strong dispersion and in addition is strongly nonlinear. As this type of waveguide contains multiple dispersion coefficients according to the degrees of spatial variation within it, our work in this article is to see how these dispersions and nonlinearities each influence the wave or the signal that can propagate in the waveguide. Since the partial differential equation which governs the dynamics of propagation in such transmission medium presents several dispersion and nonlinear coefficients, we check how they contribute to the choices of the solutions that we want them to verify this nonlinear partial differential equation. This effectively requires an adequate choice of the form of solution to be constructed. Thus, this article is based on three main pillars, namely: first of all, making a good choice of the solution function to be constructed, secondly, determining the exact solutions and, if necessary, remodeling the main equation such that it is possible;then check the impact of the dispersion and nonlinear coefficients on the solutions. Finally, the reliability of the solutions obtained is tested by a study of the propagation. Another very important aspect is the use of notions of probability to select the predominant solutions. 展开更多
关键词 Flattened Waveguide Solitary Wave Characteristic Coefficient Probabilities Propagation Nonlinear DISPERSIVE Partial Differential Equation
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多维城镇化与碳排放的非线性关系及其驱动机制 被引量:2
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作者 聂承静 李艺璇 +3 位作者 杜辉 张学儒 王利 张凤英 《环境科学》 北大核心 2025年第6期3524-3535,共12页
厘清多维城镇化与碳排放的内在关系及驱动机制是推动新型城镇化和“碳中和”协同发展的科学基础.基于2000~2021年环渤海地区面板统计数据和遥感影像,采用空间自相关模型探查CO_(2)排放量的时空演变规律,并运用系统动态面板回归模型研判... 厘清多维城镇化与碳排放的内在关系及驱动机制是推动新型城镇化和“碳中和”协同发展的科学基础.基于2000~2021年环渤海地区面板统计数据和遥感影像,采用空间自相关模型探查CO_(2)排放量的时空演变规律,并运用系统动态面板回归模型研判多维城镇化与CO_(2)排放量之间的非线性关系与驱动机制.结果表明:①2000~2021年,环渤海地区CO_(2)排放量总体呈上升趋势,空间集聚性不强,但2016年后,CO_(2)排放量增速放缓,空间关联特征呈现增强趋势.②环渤海地区城镇化子系统在不同发展阶段对CO_(2)排放量的影响差异显著.经济城镇化和CO_(2)排放量呈显著的倒“N”型曲线关系,符合环境库兹涅茨曲线(EKC)关系;人口城镇化与CO_(2)排放量的关系仅表现为倒“U”曲线的左侧部分,与碳排放的拐点尚有一定距离;土地城镇化对CO_(2)排放量的影响与经济城镇化相似,呈明显的倒“N”型关系.③人口规模、产业结构、外商投资、环境保护和居民消费水平对碳排放具有促进或抑制作用.④环渤海地区碳排放的时空异质性特征是城镇化各子系统与经济、社会和政策等相关要素发生相互作用、反馈、整合、重组等复杂多维动态过程的结果. 展开更多
关键词 多维城镇化 碳排放 非线性关系 驱动机制 环渤海地区
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基于ABAQUS的木材本构模型及试验验证 被引量:3
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作者 张慎 陈州 +1 位作者 李霆 熊世树 《工程力学》 北大核心 2025年第3期77-89,共13页
层板胶合木的制作流程决定了其材料性能与组胚粘结的层板木材的力学性能有着密切联系。基于木材材性试验,以樟子松为研究对象,建立了便于工程应用的木材本构模型。在弹性阶段,将木材应力-应变关系按正交各向异性及横观各向同性建模;选择... 层板胶合木的制作流程决定了其材料性能与组胚粘结的层板木材的力学性能有着密切联系。基于木材材性试验,以樟子松为研究对象,建立了便于工程应用的木材本构模型。在弹性阶段,将木材应力-应变关系按正交各向异性及横观各向同性建模;选择Yamada-Sun强度准则及简化的Hashin强度准则作为木材屈服的判定依据;以正则化假设和一致性条件描述木材塑性发展的流动法则,采用弹塑性回退映射算法,将应力点约束在屈服面上;通过引入连续损伤因子,对应力折减模拟木材在拉、剪作用下发生脆性破坏;采用Ziegler随动硬化模型,控制屈服面的转移实现木材受压屈服后的应变硬化。编写用户材料子程序将木材本构模型嵌入ABAQUS中,并开展了胶合木梁柱节点试验与精细化有限元数值分析,试验结果与模拟结果吻合良好。分析结果表明:清材小试件材性试验和胶合木梁柱节点转动试验有限元模型可以有效地描述木材受压硬化、拉剪损伤演化,及节点受力非线性行为,验证了该文建立的木材本构模型的有效性。 展开更多
关键词 层板胶合木 本构关系 正交各向异性 横观各向同性 弹塑性理论 节点转动性能 非线性分析
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计及铁心非线性的变压器空间动态磁场加速计算方法 被引量:2
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作者 司马文霞 孙佳琪 +3 位作者 杨鸣 邹德旭 彭庆军 王劲松 《电工技术学报》 北大核心 2025年第5期1559-1574,共16页
快速获得变压器空间磁场动态分布是构建变压器数字孪生体的基础之一,然而现有快速计算方法难以快速、准确地获得铁心饱和工况下的磁场分布特性。因此,该文提出了计及铁心非线性的变压器空间动态磁场加速计算方法。首先,构建变压器电磁... 快速获得变压器空间磁场动态分布是构建变压器数字孪生体的基础之一,然而现有快速计算方法难以快速、准确地获得铁心饱和工况下的磁场分布特性。因此,该文提出了计及铁心非线性的变压器空间动态磁场加速计算方法。首先,构建变压器电磁场路耦合仿真模型,对关键变量进行参数化扫描,仿真获得不同非线性工况下的大量磁场数据,构建涉及铁心非线性工况的主磁通和漏磁通数据集;其次,提出融合卷积神经网络(CNN)和长短期记忆网络(LSTM)的双分支深度学习模型,训练提取磁场数据的空间和时间特征,解决主、漏磁通差异大造成的模型训练难题;最后,利用模型获得输入电压、电流与内部空间磁场分布的非线性映射关系,实现空间动态磁场的加速计算,为变压器数字孪生体的构建提供了快速获得磁场数据的方法。 展开更多
关键词 非线性 卷积神经网络 长短期记忆网络 磁场 加速计算
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基于FWD三参数的路基模量预测方法 被引量:1
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作者 张磊 张定一 +2 位作者 肖倩 王龙 姚鹏飞 《哈尔滨工业大学学报》 北大核心 2025年第3期25-33,共9页
为了建立能够客观准确评价既有路基承载能力状况的测算方法,改善路面模量反算软件因初值选取不唯一而导致的误差问题,建立了路面弹性层状体系有限元动力模型,基于相关性分析筛选优化了弯沉盆参数,提出了基于BDI-F 2-d 9的三参数路基模... 为了建立能够客观准确评价既有路基承载能力状况的测算方法,改善路面模量反算软件因初值选取不唯一而导致的误差问题,建立了路面弹性层状体系有限元动力模型,基于相关性分析筛选优化了弯沉盆参数,提出了基于BDI-F 2-d 9的三参数路基模量预测模型;在此基础上形成多层路面模量反算新方法,并利用北京RIOHTrack环道的4种不同典型路面结构的实测数据对该模型的有效性和准确性进行验证。结果表明:应用所提出的FWD三参数预测模型计算得到的路基模量较常规反算方法更为准确,且与承载板实测值之间存在较好的线性关系(R^(2)=0.9106),两者比值介于0.19~0.28之间,符合已有文献研究结论。以此路基模量预测值作为输入参数并利用沥青路面动力有限元模型能更加准确地模拟FWD测试动态过程,从而提高了路面各层模量的反算精度。研究成果为模量反算软件初值选取提供了参考,并为利用弯沉盆参数(DBP指标)构建适用于实际工程的路基、路面模量反算方法提供了理论依据。 展开更多
关键词 道路工程 FWD模型 非线性特性 路基模量反算
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利用匹配滤波的调频连续波激光测距技术研究 被引量:2
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作者 张鹏 封治华 +5 位作者 张鹏飞 赵渊明 阮友田 韩文杰 张辉 康朝阳 《激光技术》 北大核心 2025年第1期53-61,共9页
基于差频解算的调频连续波激光测距技术存在测量距离短、易受噪声干扰、受非线性调频影响大的问题。为了在相同机制条件下解决此问题,提出了基于匹配滤波的调频连续波激光测距方法,改进相干探测光路,加入信号反转单元和信号共轭单元,将... 基于差频解算的调频连续波激光测距技术存在测量距离短、易受噪声干扰、受非线性调频影响大的问题。为了在相同机制条件下解决此问题,提出了基于匹配滤波的调频连续波激光测距方法,改进相干探测光路,加入信号反转单元和信号共轭单元,将混频器换成卷积器,同时满足系统响应与发射波形匹配,并进行了相关仿真实验。结果表明,相比差频解算方法,匹配滤波方法可实现两倍于差频解算方法的测距范围,信噪比提高了9.5 dB,在非线性调频误差为19.8 MHz、198 MHz和396 MHz条件下均能得到较高分辨率的距离谱,表现出较好的抵抗非线性调频的能力。此研究可为该领域的科研工作者提供技术指导和新的思路。 展开更多
关键词 激光技术 调频连续波 匹配滤波 激光测距 信噪比 非线性
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基于强化学习的非线性输入受限系统最优控制 被引量:1
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作者 高晓格 韩淑云 《计算机应用与软件》 北大核心 2025年第2期287-291,298,共6页
针对一类输入受限的非线性系统最优跟踪控制问题,提出一种基于强化学习的自适应动态规划的控制策略。通过设计一种合适的性能指标函数解决控制系统输入受限问题;通过设计评价神经网络来估计系统的最优性能指标函数,从而求解控制系统HJB(... 针对一类输入受限的非线性系统最优跟踪控制问题,提出一种基于强化学习的自适应动态规划的控制策略。通过设计一种合适的性能指标函数解决控制系统输入受限问题;通过设计评价神经网络来估计系统的最优性能指标函数,从而求解控制系统HJB(Hamilton-Jacobi-Bellman)方程,获得最优控制输入;利用Lyapunov方法获得评价网络的权重更新率,并证明系统的跟踪误差和评价网络的权重估计误差为最终一致有界(UUB);通过数值仿真实验验证该控制策略的有效性。 展开更多
关键词 非线性系统 输入受限 强化学习 自适应动态规划
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旋翼无人机吊运系统研究综述 被引量:1
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作者 梁潇 刘冰冰 +3 位作者 叶慧樱 裴腾飞 于海 方勇纯 《控制与决策》 北大核心 2025年第4期1079-1097,共19页
随着低空经济进入快速发展期,旋翼无人机凭借其垂直起降能力、高机动性及成本低廉等优势,引起了人们的广泛关注.利用其进行物资装备的空中运输能克服地形地势对运输的限制,较地面运输更为高效.在旋翼无人机空中运输领域,吊绳悬挂方式具... 随着低空经济进入快速发展期,旋翼无人机凭借其垂直起降能力、高机动性及成本低廉等优势,引起了人们的广泛关注.利用其进行物资装备的空中运输能克服地形地势对运输的限制,较地面运输更为高效.在旋翼无人机空中运输领域,吊绳悬挂方式具有机械成本低、对负载体积无限制等优势,因此具有更好的任务适应性.然而,旋翼无人机本身具有欠驱动特性,随着悬挂负载的引入,系统的自由度更高、非线性程度和状态耦合也更为严重,为其控制与规划方案的设计带来了巨大挑战.鉴于此,首先对无人机吊运系统进行分类并简要介绍其特性;然后分别对单机和多机吊运系统的控制及规划方法研究现状与最新进展进行重点阐述;最后对旋翼无人机吊运领域的已有研究进行讨论与总结,并展望该领域未来的发展和趋势. 展开更多
关键词 旋翼无人机 吊运负载 协作运输 运动规划 非线性系统
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岩石非线性黏弹塑性损伤蠕变模型研究 被引量:1
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作者 陈有亮 肖鹏 +2 位作者 杜曦 王苏然 RAFIG A 《应用力学学报》 北大核心 2025年第1期133-140,共8页
准确描述岩石蠕变行为的各阶段特征对岩石力学与岩体工程的研究具有重要的意义。由于经典元件组合模型不能较好地描述岩石蠕变过程中的非线性特征,基于损伤力学理论及Kachanov蠕变损伤演化规律,通过改进传统的Kelvin模型和村山体模型,... 准确描述岩石蠕变行为的各阶段特征对岩石力学与岩体工程的研究具有重要的意义。由于经典元件组合模型不能较好地描述岩石蠕变过程中的非线性特征,基于损伤力学理论及Kachanov蠕变损伤演化规律,通过改进传统的Kelvin模型和村山体模型,建立起能够描述岩石衰减蠕变阶段和加速蠕变阶段的非线性函数。将弹性体、线性Kelvin体、非线性Kelvin体、损伤黏弹塑性体进行串联,建立能够同时描述岩石瞬时弹性应变、非线性黏弹性应变、非线性黏塑性应变和黏性应变的非线性黏弹塑性损伤蠕变模型,采用Origin软件的Levenberg-Marquardt算法对模型参数进行了辨识,最后通过用不同应力水平下的砂岩单以及三轴压缩蠕变试验,验证该模型的合理性。结果表明:试验曲线和理论曲线的吻合度较高,所建模型不仅能够准确地描述岩石的瞬时弹性应变阶段、等速蠕变阶段的蠕变曲线特征,而且能够较好地描述衰减蠕变阶段和加速蠕变阶段蠕变曲线的非线性特征,验证了该模型的合理性与准确性。 展开更多
关键词 岩石力学 损伤 非线性 加速蠕变 黏弹塑性蠕变模型
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一种基于CHABOCHE模型参数的疲劳寿命预测模型 被引量:1
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作者 张禄 任春晓 +1 位作者 高金 刘宏利 《中南大学学报(自然科学版)》 北大核心 2025年第1期258-268,共11页
通过对相邻应力之比、材料S-N特性曲线双对数斜率及前一级疲劳累积损伤3项要素的分析,提出一种基于CHABOCHE模型参数的非线性疲劳寿命预测模型。该模型在参考多个非线性疲劳模型作用系数构成要素基础上,分析疲劳寿命预测模型所涉及构成... 通过对相邻应力之比、材料S-N特性曲线双对数斜率及前一级疲劳累积损伤3项要素的分析,提出一种基于CHABOCHE模型参数的非线性疲劳寿命预测模型。该模型在参考多个非线性疲劳模型作用系数构成要素基础上,分析疲劳寿命预测模型所涉及构成函数要素,结合已有疲劳试验数据分析,并引入CHABOCHE模型的参数,提出一种用于疲劳寿命预测的新的作用系数。运用两级及多级疲劳试验数据,分别计算并对比MINER模型、MANSON-HALFORD模型、YG模型、YUE模型、HAGHGOUEI模型、GAO模型、ZHAO模型、ZHANG模型、SUBRAMANYAN模型、HASHIN模型及新模型的疲劳寿命预测结果。研究结果表明:本文提出的新模型的疲劳寿命预测精度更高,该模型在多级应力载荷下的金属材料结构设计与疲劳寿命预测方面具有工程应用价值及实际意义。 展开更多
关键词 CHABOCHE模型 非线性模型 多级应力 疲劳损伤 寿命预测
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