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Lax integrability and superposition wave solutions of(3+1)-dimensional generalized Calogero–Bogoyavlenskii–Schiff equation
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作者 Taogetusang Bao Xiaole Zhang 《Communications in Theoretical Physics》 2025年第10期71-84,共14页
In this article,a Generalized Calogero-Bogoyavlenskii-Schiff(CBS)equation is studied,serving as an extended shallow water wave model in higher dimensions.Firstly,utilizing the Bell polynomial method,the bilinear form ... In this article,a Generalized Calogero-Bogoyavlenskii-Schiff(CBS)equation is studied,serving as an extended shallow water wave model in higher dimensions.Firstly,utilizing the Bell polynomial method,the bilinear form of the equation,bilinear Bäcklund transformation,Lax pair and infinite conservation laws are derived,confirming the equation’s complete integrability in the context of the Lax pair.Subsequently,the nonlinear superposition formula of the equation is constructed based on the derived bilinear Bäcklund transformation and an array of infinite superposition soliton solutions of the equation are formulated using this nonlinear superposition formula.Lastly,leveraging the obtained bilinear equation,infinite superposition solutions of various functional types are constructed.Their dynamic characteristics are analyzed through illustrated solution images.It is noteworthy that this paper not only uncovers a multitude of properties through the Bell polynomial method but also derives both infinite linear and nonlinear superposition solutions,enriching the diversity of solutions,these aspects have not been previously explored in existing literature. 展开更多
关键词 Bell-polynomial method Lax integrability nonlinear superposition formula infinite superposition solutions (3+1)-dimensional generalized CBS equation
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Beyond Classical Limits:Quantum Superposition and Inner Friction in a Quantum Mechanical Engine
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作者 Dehua Liu Yingying Hong Jianhui Wang 《Chinese Physics Letters》 2025年第8期1-14,共14页
We propose a quantum Otto engine operating through a cycle of two isochoric processes,where the working substance interacts with a single-mode radiation field,and two unitary strokes,during which the working substance... We propose a quantum Otto engine operating through a cycle of two isochoric processes,where the working substance interacts with a single-mode radiation field,and two unitary strokes,during which the working substance is decoupled from the field.We investigate the influence of quantum superposition and quantum internal friction on the engine's power output and efficiency,demonstrating that these quantum effects enhance both performance metrics.While these enhancements are accompanied by increased power fluctuations,we show that such fluctuations can be effectively mitigated through careful selection of control parameters.Our results reveal that the proposed quantum Otto engine can achieve performance regimes that are thermally inconceivable in classical systems,including surpassing the Otto efficiency limit and attaining 100%efficiency with nonzero power output. 展开更多
关键词 quantum effects unitary strokesduring quantum otto engine power fluctua quantum internal friction quantum superposition isochoric processeswhere
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Multi-component decompositions,linear superpositions,and new nonlinear integrable coupled KdV-type systems
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 2025年第2期1-12,共12页
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit... In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables. 展开更多
关键词 integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system
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Ultrahigh-resolution atomic localization via superposition of standing waves
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作者 Muhammad Idrees Ahmed S Hendy Zareen A Khan 《Communications in Theoretical Physics》 2025年第3期57-65,共9页
In this study we theoretically demonstrate ultrahigh-resolution two-dimensional atomic localization within a three-levelλ-type atomic medium via superposition of asymmetric and symmetric standing wave fields.Our anal... In this study we theoretically demonstrate ultrahigh-resolution two-dimensional atomic localization within a three-levelλ-type atomic medium via superposition of asymmetric and symmetric standing wave fields.Our analysis provides an understanding of the precise spatial localization of atomic positions at the atomic level,utilizing advanced theoretical approaches and principles of quantum mechanics.The dynamical behavior of a three-level atomic system is thoroughly analyzed using the density matrix formalism within the realm of quantum mechanics.A theoretical approach is constructed to describe the interaction between the system and external fields,specifically a control field and a probe field.The absorption spectrum of the probe field is thoroughly examined to clarify the spatial localization of the atom within the proposed configuration.A theoretical investigation found that symmetric and asymmetric superposition phenomena significantly influence the localized peaks within a two-dimensional spatial domain.Specifically,the emergence of one and two sharp localized peaks was observed within a one-wavelength domain.We observed notable influences of the intensity of the control field,probe field detuning and decay rates on atomic localization.Ultimately,we have achieved an unprecedented level of ultrahigh resolution and precision in localizing an atom within an area smaller thanλ/35×λ/35.These findings hold promise for potential applications in fields such as Bose-Einstein condensation,nanolithography,laser cooling,trapping of neutral atoms and the measurement of center-of-mass wave functions. 展开更多
关键词 ultrahigh resolution atom localization symmetric and asymmetric superposition probe absorption standing wave fields
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Multilevel NAND Flash Memories with Superposition Modulation:A Non-Orthogonal Multi-User Communication Perspective
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作者 Zhou Xuan Ma Zheng +2 位作者 Zhou Yi Tang Xiaohu Fan Pingzhi 《China Communications》 2025年第3期132-147,共16页
In this work,we propose a comprehensive theoretical framework for the multilevel NAND(NOT AND logic)flash memory,built upon the modified Student’s t distribution where the distortion of the threshold voltage caused b... In this work,we propose a comprehensive theoretical framework for the multilevel NAND(NOT AND logic)flash memory,built upon the modified Student’s t distribution where the distortion of the threshold voltage caused by the random telegraph noise,cell-to-cell interference and data retention noise are jointly considered.Based on the superposition modulation,we build a non-orthogonal multiuser communication model where a linear mapping is conducted between the verify voltages and binary antipodal symbols.Aimed at improving the storage efficiency,we propose an unequal amplitude mapping(UAM)solution by optimizing the weighting coefficients of verify voltages to intelligently adjust the width of each state.Moreover,the uniform storage efficiency region and sum storage efficiency of different labelings with various decoding schemes are discussed.Simulation results validate the effectiveness of our proposed UAM solution where an up to 20.9%storage efficiency gain can be achieved compared to the current used benchmark scheme.In addition,analytical and simulation results also demonstrate that the successive cancellation decoding outperforms other decoding schemes for all labelings. 展开更多
关键词 binary labelings flash memory modified Student’s t-based model superposition modulation unequal amplitude mapping
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Fast and robust production of quantum superposition states by the fractional shortcut to adiabaticity
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作者 Guan-Qiang Li Hao Guo +2 位作者 Yu-Qi Zhang Bo Yang Ping Peng 《Communications in Theoretical Physics》 2025年第1期54-64,共11页
The fractional shortcut to adiabaticity(f-STA)for the production of quantum superposition states is proposed firstly via a three-level system with aΛ-type linkage pattern and a four-level system with a tripod structu... The fractional shortcut to adiabaticity(f-STA)for the production of quantum superposition states is proposed firstly via a three-level system with aΛ-type linkage pattern and a four-level system with a tripod structure.The fast and robust production of the coherent superposition states is studied by comparing the populations for the f-STA and the fractional stimulated Raman adiabatic passage(f-STIRAP).The states with equal proportions can be produced by fixing the controllable parameters of the driving pulses at the final moment of the whole process.The effects of the pulse intensity and the time delay of the pulses on the production process are discussed by monitoring the populations on all of the quantum states.In particular,the spontaneous emission arising from the intermediate state is investigated by the quantum master equation.The result reveals that the f-STA exhibits superior advantages over the f-STIRAP in producing the superposition states. 展开更多
关键词 quantum population transfer shortcut to adiabaticity coherent superposition states dark states spontaneous emission
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Efficient fault-tolerant circuit for preparing quantum uniform superposition states via quantum measurement
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作者 Xiang-Qun Fu Tian-Ci Tian +4 位作者 Hong-Wei Li Jian-Hong Shi Xiao-Liang Yang Tan Li Wan-Su Bao 《Chinese Physics B》 2025年第12期53-59,共7页
Preparing quantum superposition states is a crucial step in realizing quantum algorithms,which demands substantial resources.In this paper,we propose a new method for preparing quantum uniform superposition states via... Preparing quantum superposition states is a crucial step in realizing quantum algorithms,which demands substantial resources.In this paper,we propose a new method for preparing quantum uniform superposition states via quantum measurement,and design the bitwise implementation circuit,which only contains Hadamard,CNOT,and π/8 phase gates.Compared to the Shukla–Vedula method,the number of quantum gates required by both methods scales the same,while,the new method offers stronger fault tolerance,and the ancillary qubits employed during the implementation process can be reused,making it more suitable for implementation on real quantum computers.As an application,we provide the circuit for Shor's discrete logarithm quantum algorithm,based on the new method,demonstrating its technical advantage for implementation of quantum algorithms. 展开更多
关键词 quantum superposition state quantum measurement quantum computing algorithm quantum circuit
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低速重载输送链传动系统动力学建模及特性研究
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作者 陈立锋 张俊博 肖钊 《机械传动》 北大核心 2026年第1期87-91,共5页
【目的】针对低速重载输送链传动存在的爬行现象及运动平稳性差的问题,基于多刚体动力学理论,建立了低速重载输送链传动动力学模型,开展了动力学特性研究,为提高低速重载输送链传动系统的平稳性提供参考。【方法】考虑低速重载输送链传... 【目的】针对低速重载输送链传动存在的爬行现象及运动平稳性差的问题,基于多刚体动力学理论,建立了低速重载输送链传动动力学模型,开展了动力学特性研究,为提高低速重载输送链传动系统的平稳性提供参考。【方法】考虑低速重载输送链传动系统的结构特点及输送载荷的影响,利用胡克定律模拟输送链节点的力学特性,构建了输送链107自由度动力学模型;采用模态叠加法对动力学模型进行求解,得到了低速重载输送链的动力学特性,研究了输送链的松边悬垂度和紧边摩擦力对传动速度变化的影响规律。【结果】结果表明,降低松边悬垂度、减小链条与导轨间的摩擦因数,可有效减少输送链传动爬行现象的产生,提高输送链传动系统的运动平稳性。 展开更多
关键词 输送链传动 平稳性 爬行现象 动力学 模态叠加
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谐波电流允许值分配关键参数取值方法
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作者 陶顺 陈慧琳 +2 位作者 徐永海 周胜军 肖湘宁 《中国电力》 北大核心 2026年第3期114-124,共11页
GB/T 14549自颁布实施以来,有效监督了电网中的谐波问题,保证了电能质量。随着新型电力系统的发展,电网中的谐波呈现新特征,GB/T 14549难以完全适应当前电网发展与现代管理需求。针对新型电力系统中的谐波特征,基于GB/T 14549的谐波电... GB/T 14549自颁布实施以来,有效监督了电网中的谐波问题,保证了电能质量。随着新型电力系统的发展,电网中的谐波呈现新特征,GB/T 14549难以完全适应当前电网发展与现代管理需求。针对新型电力系统中的谐波特征,基于GB/T 14549的谐波电流允许值分配方法,分别针对总谐波电流约束指标、供电容量取值方法和叠加方法,给出关键参数的取值方法,通过案例验证其合理性与有效性,有效约束了谐波注入,为谐波国家标准修订提供参考。 展开更多
关键词 GB/T 14549 总谐波电流约束 供电容量 谐波叠加
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基于三维电磁态势的多雷达威力包络融合研究
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作者 刘艳平 程芳 《计算机测量与控制》 2026年第1期221-226,234,共7页
对三维电磁态势中多雷达威力包络融合与效能计算课题进行了研究,分析了当前透明度叠加法、等值面提取法、体素着色法等多雷达叠加效果计算方法存在简单叠加视觉度差、复杂融合边界不精细、分辨率差及对硬件依赖过大等问题;采用将非相干... 对三维电磁态势中多雷达威力包络融合与效能计算课题进行了研究,分析了当前透明度叠加法、等值面提取法、体素着色法等多雷达叠加效果计算方法存在简单叠加视觉度差、复杂融合边界不精细、分辨率差及对硬件依赖过大等问题;采用将非相干概率叠加引入包络融合以降低对相位等信息的依赖,利用梯度控制扩散法实现平滑过渡与边缘保持统一,结合八叉树+GPU加速策略提升算法计算和可视化效率的技术方法,其技术创新点在于非相干概率叠加的引入、梯度控制扩散法的应用以及八叉树与GPU加速的结合;经仿真试验测试,该方法在3部雷达同态势中,重叠区域的探测概率达0.92,较单雷达最高值(0.85)提升8.2%;平滑前概率场梯度模长标准差为0.15,平滑后降至0.07;存储量降低76%,同时等值面渲染精度损失<2%;算法实践显示,在高刷新率下实现包络融合平滑、边界界面清晰及减少对雷达参数的依赖;经实际应用满足了提高融合包络呈现效果和用户视觉感的应用需求,对用户了解装备性能边界具有重要作用。 展开更多
关键词 包络融合 透明度叠加法 边界扩散 八叉树
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Influence of electron-beam superposition welding on intermetallic layer of Cu/Ti joint 被引量:3
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作者 陈国庆 张秉刚 +1 位作者 刘伟 冯吉才 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2416-2420,共5页
QCr0.8 was electron-beam welded to TC4 and the effect of the intermetallic layer (IMC-layer) on the mechanical properties of the joint was investigated. The IMC-layers are joint weaknesses at the Cu fusion line in c... QCr0.8 was electron-beam welded to TC4 and the effect of the intermetallic layer (IMC-layer) on the mechanical properties of the joint was investigated. The IMC-layers are joint weaknesses at the Cu fusion line in centered welding and at the Ti fusion line when the beam is deviated towards Cu. A new method referred to as electron-beam superposition welding was presented, and the optimal welding sequence was considered. The IMC-layer produced by centered welding was fragmented and remelted during Cu-side non-centered welding, giving a finely structured compound layer and improved mechanical properties of the joint. The tensile strength of joint is 276.0 MPa, 76.7% that of the base metal. 展开更多
关键词 Cu alloy Ti alloy electron beam superposition welding IMC-layer
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基于磁荷叠加增强的磁扭负刚度低频隔振研究
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作者 董光旭 施永伟 +4 位作者 罗亚军 张希农 陈恩伟 魏浩征 陈品 《航空学报》 北大核心 2026年第2期136-153,共18页
低频扭转振动不仅会降低轴系结构的动力传输效率,还会严重威胁轴系结构的安全运行,成为低频振动控制领域中的研究热点。针对当前应用于轴系结构低频隔振的负刚度机构存在强非线性、负刚度小的问题,基于磁荷叠加原理提出一种高磁扭负刚... 低频扭转振动不仅会降低轴系结构的动力传输效率,还会严重威胁轴系结构的安全运行,成为低频振动控制领域中的研究热点。针对当前应用于轴系结构低频隔振的负刚度机构存在强非线性、负刚度小的问题,基于磁荷叠加原理提出一种高磁扭负刚度扭转隔振器设计方法。通过将沿环向磁化的磁瓦按磁荷叠加方式布置获取的高磁扭负刚度弹簧(High Magnetic Torsional Negative Stiffness Spring,HMTS)与平面涡卷扭簧并联开展轴系结构的低频扭振隔离特性分析,采用磁荷模型建立高磁扭负刚度弹簧的扭矩、磁扭负刚度理论模型,结合COMSOL有限元软件对比研究高磁扭负刚度弹簧与传统磁负刚度弹簧的扭转负刚度特性,利用Ansys Workbench仿真分析平面涡卷弹簧的力学性能,建立隔振系统的动力学模型,通过谐波平衡法仿真研究隔振系统的低频扭振隔离性能,制备并测试高磁扭负刚度扭转隔振器的扭转隔振性能。结果表明:基于磁荷叠加增强的高磁扭负刚度较传统磁负刚度具有高出近1倍的负刚度数值,显著拓宽了轴系扭转振动的低频隔振带宽。 展开更多
关键词 低频扭转振动 磁扭负刚度 磁荷叠加 隔振
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Parametric analyses on dynamic response of an offshore pier under action of wind and wave
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作者 HE Xu-hui XU Hong-gang +1 位作者 NAEEM Muhammad JING Hai-quan 《Journal of Central South University》 2026年第1期466-483,共18页
Offshore structures are constantly subjected to the complex forces of the marine environment,including wind,sea waves,currents,and seismic loadings.Among these,wind and sea wave forces persist throughout the structure... Offshore structures are constantly subjected to the complex forces of the marine environment,including wind,sea waves,currents,and seismic loadings.Among these,wind and sea wave forces persist throughout the structure’s lifetime.This study proposes a dynamic analysis approach that incorporates both time and frequency domain methods to investigate the structural responses of offshore structures under the combined effects of wind and wave forces.A wind wave-pier coupling dynamic model is first developed using a small-scale single pier,with corresponding dynamic equilibrium equations established.Fluctuating wind and sea waves are simulated using the weighted amplitude wave superposition(WAWS)method and linear superposition,respectively.Wind and wave load histories are then derived via Fourier transforms.The structural dynamic responses under different loading scenarios(wind only,wave only,and combined wind and wave)are analyzed using the Newmarkβmethod.Additionally,the effects of varying wind and wave parameters on structural responses are evaluated.The simulation results demonstrate that the structural responses to wind-wave coupling are smaller than the superimposed effects of wind and wave forces acting independently.When wind speeds are relatively low,wave forces dominate structural displacement and serve as the primary source of vibration. 展开更多
关键词 coupling actions of wind and wave weighted amplitude wave superposition linear superposition dynamic analysis Newmark-βmethod
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Vibrations induced by time-delayed double blastholes in underground rocks:Experimental study and theoretical analysis
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作者 Yonggang Gou Gui Yang +2 位作者 Xianyang Qiu Kun Ji Yumin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1108-1125,共18页
Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while... Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while the potential for further vibration reduction remains debated,largely due to unclear underlying mechanisms.In light of the popularization of electronic detonators and the representativeness of double-hole configurationsfor multiple blastholes,it is essential to investigate the vibration characteristics induced by time-delayed double blastholes.Therefore,a series of doubleborehole experimental blasts was conducted in an underground roadway to clarify the variation in vibration from single-hole to dual-hole conditions.Based on the experimental data and inherent limitations,an exact full-fieldtheoretical model was further employed to systematically analyze the effects of delay time,charge length,and borehole inclination angle on vibrations induced by various doublehole configurations.The experimental data and theoretical analysis reveal that the general scaled distance effectively predicts vibrations in delayed blasting but does not reflectvibration reduction.Increasing delay time causes fluctuatingPPVs,which stabilize slightly above single-hole PPVs as delay times exceed a certain value.The delayed blasting primarily reduces near-fieldfrequencies.Longer charge lengths in double boreholes increase PPV levels and attenuation rates within a certain length,and the vibration behavior of combined long and short charge lengths is governed by the long blasthole.Larger blasthole inclination angles enhance vibration amplitude and reduce PPV attenuation rates.Optimizing inclination angles is more critical than adjusting delay times,and parallel boreholes offer the best vibration control. 展开更多
关键词 Vibration of double blastholes Experimental data Theoretical model Delay time Wave superposition
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隧道水封爆破装药结构的优化与应用
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作者 赵海涛 杨贤 +3 位作者 刘丙宇 张彦龙 高文学 张小军 《爆破器材》 北大核心 2026年第1期45-54,共10页
采用水封爆破进行隧道掘进时,不同水介质比和装药结构对爆破效果影响显著。基于Starfield迭代法,推导了水封爆破时炮孔孔壁冲击压力的理论计算公式。采用数值模拟,进一步研究了水封爆破时不同装药结构对孔壁冲击压力的影响和围岩的损伤... 采用水封爆破进行隧道掘进时,不同水介质比和装药结构对爆破效果影响显著。基于Starfield迭代法,推导了水封爆破时炮孔孔壁冲击压力的理论计算公式。采用数值模拟,进一步研究了水封爆破时不同装药结构对孔壁冲击压力的影响和围岩的损伤特征。基于最优装药结构,进行了现场爆破试验。研究表明:不同水介质比下,孔壁压力的变化规律相似,呈先增大、后减小、最后趋于稳定的变化趋势。其中,孔壁压力在装药段最大;且随着与炸药和水介质交界面距离的增大,孔壁压力逐渐减小。水介质的存在可以减缓爆炸应力波的衰减,提高炸药能量的利用率。随着水介质比的增大,围岩损伤逐渐降低。水介质比介于0.2~0.3时,可有效提高破岩效率。相比于孔口水间隔装药与孔底水间隔装药,两端水间隔装药爆破后岩体破碎均匀,爆破效果良好。 展开更多
关键词 水封爆破 水介质比 Starfield迭代法 爆破损伤 工程应用
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刚柔耦合响应下的太阳翼位移场重构方法
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作者 胡本昂 赖王杰 +2 位作者 黄昌洋 林成辉 张顺琦 《动力学与控制学报》 2026年第1期55-63,共9页
随着大型柔性太阳翼在新一代航天器中的广泛应用,其刚柔耦合动力学特性引发的位移场实时监测需求日益凸显.针对现有位移场重构研究多基于静力学工况且难以适应航天器复杂动力学激励的问题,本文提出一种基于混合坐标法与模态叠加原理的... 随着大型柔性太阳翼在新一代航天器中的广泛应用,其刚柔耦合动力学特性引发的位移场实时监测需求日益凸显.针对现有位移场重构研究多基于静力学工况且难以适应航天器复杂动力学激励的问题,本文提出一种基于混合坐标法与模态叠加原理的动态位移场重构方法.通过分析刚柔耦合航天器动力学模型,结合模态分析方法构建了太阳翼全局位移场高精度重构算法.该方法能够在姿态机动与柔性振动耦合工况下,仅需少量传感数据即可实现动态位移场的实时重构.研究结果表明:本文所提方法能够在动力学激励下实现对太阳翼全局位移场的高精度重构. 展开更多
关键词 刚柔耦合航天器 动力学建模 模态叠加原理 位移场重构
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不同电场下CVT电容单元膜纸绝缘损坏机理研究
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作者 贺达 李博文 +3 位作者 杨智 郑一鸣 蔺家骏 张乔根 《高压电器》 北大核心 2026年第2期102-111,共10页
电容式电压互感器(CVT)在超/特高压电力系统中得到了广泛使用。CVT发生故障将影响电能计量的准确可靠和电网运行的稳定安全。文中以故障发生率最高的CVT电容单元为研究对象,通过制作适用于反映CVT电容心子电极缺陷的试样,搭建对应的实... 电容式电压互感器(CVT)在超/特高压电力系统中得到了广泛使用。CVT发生故障将影响电能计量的准确可靠和电网运行的稳定安全。文中以故障发生率最高的CVT电容单元为研究对象,通过制作适用于反映CVT电容心子电极缺陷的试样,搭建对应的实验平台,进行不同电场形式下的击穿实验并分析试品击穿点分布,研究了工频电压、正、负极性雷电冲击电压和交流叠加冲击复合电场下膜纸绝缘的损坏机制。实验结果表明,CVT电容心子的铝箔电极边缘缺陷是导致膜纸绝缘损坏的主要原因,电极缺陷的种类及变化决定了击穿点的空间分布规律。聚丙烯薄膜对正负空间电荷“陷阱”效果的差异性,会引起复合电场不同叠加幅值、叠加相位下击穿点主导类型的转变。 展开更多
关键词 电容式电压互感器 膜纸绝缘 交流叠加冲击复合电场 电极边缘 击穿特性
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Pekeris波导中轴对称结构辐射声场预报的联合波叠加法
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作者 刘宝 周焰 蔡亦朝 《哈尔滨工程大学学报》 北大核心 2026年第1期20-27,共8页
针对Pekeris波导条件下水下轴对称结构的声辐射预报问题,本文给出一种综合利用积分型镜像虚源与波叠加的方法,从而同时快速计算近、远场体积目标的声辐射。基于波叠加原理,将目标激发的声场看作其内部等效声源辐射声场叠加而成,并根据... 针对Pekeris波导条件下水下轴对称结构的声辐射预报问题,本文给出一种综合利用积分型镜像虚源与波叠加的方法,从而同时快速计算近、远场体积目标的声辐射。基于波叠加原理,将目标激发的声场看作其内部等效声源辐射声场叠加而成,并根据镜像虚源法建立声源强度与结构表面振速的关系方程,以此确定声源强度。进一步,利用积分形式的Green函数推导构建新型镜像法,以此构建精确反映幅值与相位的声传递函数。在此基础上,将各等效声源计算的结果代入积分形式虚源法构建的声传播函数并进行线性叠加,获取目标辐射的声场。以轴对称结构、脉动球源和摆动球源为案例,采用本文方法计算其声功率,并与Comsol有限元计算结果进行对比,结果表明本文方法具有很高计算充实精度。 展开更多
关键词 镜像虚源 波叠加 Pekeris波导 等效声源 轴对称结构 声辐射 声场预报 浅海
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基于改进脉冲−空间叠加法的LNG运输船围护系统晃荡载荷反演及应力监测
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作者 冯琛涵 李星辉 +1 位作者 袁昱超 唐文勇 《中国舰船研究》 北大核心 2026年第1期248-258,共11页
[目的]晃荡载荷是围护系统最重要且最复杂的载荷之一,却由于数值模拟和模型试验的简化不能够被准确地计算或测量。为获得准确的晃荡载荷时程特征以及实现围护系统健康实时监测,采用改进逆脉冲−空间叠加法,通过测量部分结构响应推导出晃... [目的]晃荡载荷是围护系统最重要且最复杂的载荷之一,却由于数值模拟和模型试验的简化不能够被准确地计算或测量。为获得准确的晃荡载荷时程特征以及实现围护系统健康实时监测,采用改进逆脉冲−空间叠加法,通过测量部分结构响应推导出晃荡载荷以及高应力区域(热点)响应。[方法]建立测点位置和晃荡载荷作用位置的反演数学模型,预测多区域载荷;建立晃荡载荷作用位置和热点位置的响应预测数学模型,预测多热点应力。依据杜哈梅积分建立载荷−响应方程,采用Tikhonov正则化方法求解晃荡载荷,根据L曲线法选取目标函数最优正则化参数进而得到晃荡载荷稳定正则解,并对晃荡载荷预测步长展开研究。[结果]晃荡载荷预测精度随载荷复杂度增加而降低,随载荷预测步长减小而增加。所有工况下载荷及热点应力时程曲线与真实值变化趋势一致。通过控制载荷预测步长,能够保证晃荡载荷和热点应力峰值误差分别小于10%和1%。[结论]相较于试验测量和数值模拟的正方法,载荷反演的逆方法为围护系统晃荡载荷获取提供了新思路。改进逆脉冲−空间叠加法成功用于LNG运输船围护系统晃荡载荷反演以及热点应力预测,验证了该方法应用于复合材料组合结构的可行性,可为该方法应用于其他船海结构物提供参考。 展开更多
关键词 薄膜型围护系统 液体晃荡 载荷反演 应力监测 脉冲−空间叠加法 动态载荷 液货舱
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磁场叠加下的运动分解陷阱:带电粒子轨迹的矢量合成法正析
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作者 张鼎 《物理通报》 2026年第2期50-52,共3页
运动的合成与分解是解决复杂曲线运动的核心方法,在近几年的高考题中时常出现需要运用该方法处理的实际问题,是高考的热点内容,同时也是难点内容.但在磁场问题中,因矢量的叠加性常引发误解.本文通过一道典型带电粒子在叠加磁场中运动的... 运动的合成与分解是解决复杂曲线运动的核心方法,在近几年的高考题中时常出现需要运用该方法处理的实际问题,是高考的热点内容,同时也是难点内容.但在磁场问题中,因矢量的叠加性常引发误解.本文通过一道典型带电粒子在叠加磁场中运动的问题,深入剖析常见错误,揭示运动分解的深层条件,总结在处理磁场叠加问题中需要注意的问题. 展开更多
关键词 运动的合成与分解 带电粒子在磁场中的运动 磁场的叠加
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