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Novel Analysis of SiO_(2)+ZnO+MWCN T-Ternary Hybrid Nanofluid Flow in Electromagnetic Squeezing Systems
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作者 Muhammad Hamzah Muhammad Ramzan +3 位作者 Abdulrahman A.Almehizia Ibrahim Mahariq Laila A.Al-Essa Ahmed S.Hassan 《Computer Modeling in Engineering & Sciences》 2026年第1期604-626,共23页
The present investigation inspects the unsteady,incompressible MHD-induced flow of a ternary hybrid nanofluid made of SiO_(2)(silicon dioxide),ZnO(zinc oxide),and MWCNT(multi-walled carbon nanotubes)suspended in a wat... The present investigation inspects the unsteady,incompressible MHD-induced flow of a ternary hybrid nanofluid made of SiO_(2)(silicon dioxide),ZnO(zinc oxide),and MWCNT(multi-walled carbon nanotubes)suspended in a water-ethylene glycol base fluid between two perforated squeezing Riga plates.This problem is important because it helps us understand the complicated connections between magnetic fields,nanofluid dynamics,and heat transport,all of which are critical for designing thermal management systems.These findings are especially useful for improving the design of innovative cooling technologies in electronics,energy systems,and healthcare applications.No prior study has been done on the theoretical study of the flow of ternary nanofluid(SiO_(2)+ZnO+MWCNT/Water−EthylGl ycol,(60∶40))past a pierced squeezed Riga plates using the boundary value problem solver 4th-order collocation(BVP4C)numerical approach to date.So,the current work has been carried out to fill this gap,and the core purpose of this study is to explore the aspects that enhance the heat transfer of base fluids(H_(2)O/EG)suspended with three nanomaterials SiO_(2),ZnO,and MWCNT.The Riga plates introduce electromagnetic forcing through an embedded array of magnets and electrodes,generating Lorentz forces to regulate the flow.The squeezing effect introduces dynamic boundary movement,which enhances mixing;however,permeability,due to porosity,replicates the true material limits.Similarity transformations of the Navier-Stokes and energy equations result in a highly nonlinear set of ordinary differential equations that govern momentum and thermal energy transport.The subsequent boundary value problem is solved utilizing the BVP4C numerical approach.The study observes the impact of magnetic parameters,squeezing velocity,solid volume percentages of the three nanoparticles,and porous medium factors on velocity and temperature fields.Results show that magnetic fields reduce the velocity profile by 6.75%due to increased squeezing and medium effects.Tri-hybrid nanofluids notice a 9%rise in temperature with higher thermal radiation. 展开更多
关键词 Ternary hybrid nanofluid thermal radiation MATLAB Riga plates porous medium squeezing flow electromagnetic field
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Enhanced mechanical squeezing in an optomechanical system via backward stimulated Brillouin scattering 被引量:1
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作者 Shan-Shan Chen Yi-Long Xie +4 位作者 Jing-Jing Zhang Na-Na Zhang Yong-Rui Guo Huan Yang Yong Ma 《Chinese Physics B》 2025年第1期315-322,共8页
We investigate theoretically the enhancement of mechanical squeezing in a multimode optomechanical system by introducing a coherent phonon–photon interaction via the backward stimulated Brillouin scattering(BSBS)proc... We investigate theoretically the enhancement of mechanical squeezing in a multimode optomechanical system by introducing a coherent phonon–photon interaction via the backward stimulated Brillouin scattering(BSBS)process.The coherent photon–phonon interaction where two optical modes couple to a Brillouin acoustic mode with a large decay rate provides an extra channel for the cooling of a Duffing mechanical oscillator.The squeezing degree and the robustness to the thermal noises of the Duffing mechanical mode can be enhanced greatly.When the Duffing nonlinearity is weak,the squeezing degree of the mechanical mode in the presence of BSBS can be improved by more than one order of magnitude compared with that in the absence of BSBS.Our scheme may be extended to other quantum systems to study novel quantum effects. 展开更多
关键词 mechanical squeezing optomechanical system backward stimulated Brillouin scattering Duffing nonlinearity
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Simulation and Mechanical Analysis of the Squeezing Silt Process by Riprap Using Particle Flow Code(PFC): A Case Study of Maoming Port Breakwater
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作者 YAO Yun-long LIU Xin +3 位作者 SHI Yun-qiang LENG Xin-liang ZHANG Si-qing SHAO Zhiwei 《China Ocean Engineering》 2025年第6期1176-1188,共13页
Rubble mound breakwaters, a prevalent type of sloping breakwater structure, are extensively employed in port and coastal infrastructure projects. Under soft soil foundation conditions, the process of squeezing silt by... Rubble mound breakwaters, a prevalent type of sloping breakwater structure, are extensively employed in port and coastal infrastructure projects. Under soft soil foundation conditions, the process of squeezing silt by riprap is implemented to enhance bearing capacity through soft soil replacement and compaction. However, predicting the depth law of squeezing silt by riprap and understanding its mechanism remain significant engineering design challenges.This study employs particle flow code(PFC) based on the discrete element method to simulate the squeezing silt process by riprap, examining variations in depth law under different geological conditions and its mechanical characteristics.Through calibration of the PFC model's meso-parameters via macro-experiments, the study analyzes the effects of riprap size, drop height, and soft soil properties on the depth law of squeezing silt. Findings demonstrate that riprap drop height and soft soil thickness substantially influence the depth, while appropriate calibration of meso-parameters enhances simulation accuracy. This research contributes theoretical and practical guidance for optimizing rubble mound breakwater design, understanding squeezing silt mechanisms, construction practices, and riprap quantity estimation. 展开更多
关键词 rubble mound breakwater squeezing silt by riprap particle flow code(PFC) depth law of squeezing silt by riprap riprap quantity estimation
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Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium
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作者 K.MUHAMMAD M.SARFRAZ 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期193-208,共16页
This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates.One plate remains stationary,while the other moves downward at a squeezing veloci... This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates.One plate remains stationary,while the other moves downward at a squeezing velocity.The space between these plates contains a Darcy-Forchheimer porous medium.A mixture of water-based fluid with gold(Au)and silicon dioxide(Si O2)nanoparticles is formulated.In contrast to the conventional Fourier's heat flux equation,this study employs the Cattaneo-Christov heat flux equation.A uniform magnetic field is applied perpendicular to the flow direction,invoking magnetohydrodynamic(MHD)effects.Further,the model accounts for Joule heating,which is the heat generated when an electric current passes through the fluid.The problem is solved via NDSolve in MATHEMATICA.Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow,energy transport,and skin friction.The findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies.It is observed that the squeezing motion generates additional pressure gradients within the fluid,which enhances the flow rate but reduces the frictional drag.Consequently,the fluid is pushed more vigorously between the plates,increasing the flow velocity.As the fluid experiences higher flow rates due to the increased squeezing effect,it spends less time in the region between the plates.The thermal relaxation,however,abruptly changes the temperature,leading to a decrease in the temperature fluctuations. 展开更多
关键词 convective boundary condition Darcy-Forchheimer medium hybrid nanofuid Joule heating magnetohydrodynamic(MHD) numerical solution squeezing flow regression analysis
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Countermeasures against squeezing ground:A case study of Haidong Water Conveyance Tunnel
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作者 SUN Di TAO Zhigang +6 位作者 YANG Hong LEI Xiaotian CAI Mingjiu WANG Fengnian HUO Shusen JI Yaopeng HE Manchao 《Journal of Mountain Science》 2025年第6期2291-2312,共22页
The Haidong Water Conveyance Tunnel(HWCT),a notable engineering feat located within Dali City,Yunnan Province,China,represents an ultra-long water conveyance tunnel situated in a region characterized by medium in-situ... The Haidong Water Conveyance Tunnel(HWCT),a notable engineering feat located within Dali City,Yunnan Province,China,represents an ultra-long water conveyance tunnel situated in a region characterized by medium in-situ stress conditions.As part of the Central Yunnan Water Diversion Project,this tunnel was specifically engineered for soft-rock environments.The excavation of such tunnels presents significant challenges due to rock mass deformation,commonly referred to as squeezing ground behavior.These challenges are exacerbated when navigating through diverse geological and geomorphological units,particularly in areas with complex geological conditions.To address these issues,an innovative active support system utilizing prestressed anchor cables was developed for the HWCT.This study provides a comprehensive analysis and comparison of rock mass behavior between two support systems:a conventional passive system employing steel arches and the proposed active system using prestressed anchor cables.The numerical modeling was performed using FLAC3D software to simulate various scenarios,while an extensive monitoring program was implemented in several representative tunnel sections to measure key parameters including rock mass stresses,displacements,internal forces in steel arches,and axial forces in anchor cables.The results from both the numerical simulations and field observations were systematically compared.The analyses demonstrated the superior performance of the active support system using prestressed anchor cables in the HWCT,significantly enhancing overall rock mass stability and effectively mitigating large deformation issues throughout the tunnel. 展开更多
关键词 Water conveyance tunnel Large deformation of soft rock squeezing ground Prestressed anchor cable Active support system Numerical simulations Field test
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Analysis of squeezing-induced failure in a water tunnel and measure of rehabilitation:A case study of Tishreen tunnel,Syria
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作者 Mohannad Mhanna Hussein Hadi Hussein 《Deep Underground Science and Engineering》 2025年第3期498-510,共13页
Squeezing phenomena can lead to severe loads in deep tunnels,especially in the presence of a low ratio of surrounding rock strength to overburden pressure.For this reason,it is highly imperative to analyze and identif... Squeezing phenomena can lead to severe loads in deep tunnels,especially in the presence of a low ratio of surrounding rock strength to overburden pressure.For this reason,it is highly imperative to analyze and identify a suitable methodology to estimate the squeezing potential and select a proper support system of rock mass.This study aims to reveal the causes of failure of Tishreen tunnel in the west of Syria and develop remediation measures accordingly so as to bring the tunnel back into service.The tunnel in question was subjected to successive failures such as buckling and spalling of side walls,floor heave,and extremely large convergence reaching the failure state of the tunnel lining.In this study,an effective way was demonstrated to evaluate the squeezing potential of the tunnel lining and appropriate modeling of the long-term response of a tunnel excavated in weak rock.Specifically,the causes of failure of Tishreen tunnel were first evaluated by empirical approaches.Then,a numerical model was developed using a timedependent constitutive model to investigate the time-dependent response of the tunnel lining.On this basis,this study proposed an effective reinforcement schemes including steel ribs,grout injection,ground anchors,and new lining of reinforced concrete.The results show that the Burger viscoplastic model simulates effectively the resulting deformation and creep behavior of squeezing ground.It is also observed that using a combined heavy support system can provide efficient control over squeezing deformation and maintain the serviceability of the tunnel under study. 展开更多
关键词 Burger-creep viscoplastic model floor heave grout injection squeezing potential steel ribs tunnel support
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镁基复合材料挤压铸造制备技术研究
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作者 陈利文 李佳成 +4 位作者 赵源 景舰辉 樊如意 侯华 赵宇宏 《铸造技术》 2026年第1期16-24,共9页
镁基复合材料具有优异的性能,但制备工艺上仍存在着不足之处。为此,通过分子模拟与实验相结合的方法,系统研究了氧化石墨烯(GO)增强ZM5镁基复合材料的界面特性、微观组织及力学性能。计算结果表明,经PVA表面处理后的GO/PVA-Al界面结合... 镁基复合材料具有优异的性能,但制备工艺上仍存在着不足之处。为此,通过分子模拟与实验相结合的方法,系统研究了氧化石墨烯(GO)增强ZM5镁基复合材料的界面特性、微观组织及力学性能。计算结果表明,经PVA表面处理后的GO/PVA-Al界面结合能显著高于未处理的GO/Al界面,表明表面处理法制备的增强体可有效增强界面结合,有助于提升复合材料整体性能。微观组织分析显示,添加0.3%(质量分数)GO并挤压铸造后,复合材料中α-Mg基体由树枝晶转变为等轴晶,晶粒显著细化,β-Mg17Al12第二相析出减少且分布更均匀。与基体合金相比,GO/ZM5复合材料的硬度提高了23.1%,抗拉强度提升了8.1%,断口形貌由脆性断裂转变为韧性断裂。研究表明,GO的添加通过细化晶粒和改善界面结合,显著增强了ZM5镁基复合材料的综合力学性能。 展开更多
关键词 氧化石墨烯 镁基复合材料 表面处理 挤压铸造 细化晶粒
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布桩形式对边坡变形特性影响的透明土试验研究
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作者 张秀勇 张百红 尹海峰 《防灾减灾工程学报》 北大核心 2026年第1期200-210,共11页
原稳定边坡坡顶受工程作用影响会产生附加变形甚至失稳,针对抗滑桩布置方案问题,进行了三种工况的透明土模型试验,位移场采集数据显示:随着坡顶竖向位移荷载的施加,土体变形量逐渐增大,变形区域由桩前逐渐传递至桩后;不同水平剖面土体... 原稳定边坡坡顶受工程作用影响会产生附加变形甚至失稳,针对抗滑桩布置方案问题,进行了三种工况的透明土模型试验,位移场采集数据显示:随着坡顶竖向位移荷载的施加,土体变形量逐渐增大,变形区域由桩前逐渐传递至桩后;不同水平剖面土体的变形规律也不同,加载区域的土体受到挤压向侧面移动,但变形量逐渐减小,加载平台前的土体和加载平台下的部分土体受到挤压向平台与桩体之间的区域移动,位移先增大后减小,三种布桩形式下的土体变形规律不尽相同,单桩布置在坡顶时,荷载较大时,桩体附近土颗粒会出现绕流作用,坡体产生较大水平位移且靠近坡面土体有向上位移;排桩布置在坡顶时,选择适当桩距,桩前土出现压力拱,阻隔压力传递,坡脚平台面以下土体受到加载平台的影响很小,而坡脚平台以上斜坡区域的土体与下部土体变形较大,排桩结构把外荷载作用效应向深部转移,深部桩及土体抗力较大,群桩效应明显,加固效果较好;排桩布置在坡中时,排桩不在平台加载主要影响区内,桩前土体位移没有有效控制,下滑力增加,滑动面在桩前已经形成,加载平台下沉一定深度后坡脚发生剪切破坏,滑裂面从桩身下部穿过,排桩加固失效,桩间距及布桩位置是影响边坡体加固效果的关键因素。 展开更多
关键词 透明土 抗滑桩 堆载 挤土效应 模型试验
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大型钢铁件液态模锻技术研究与应用
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作者 邢书明 吴征天 石洪伟 《铸造》 2026年第3期252-257,共6页
首先提出了大型钢铁件液态模锻的三个技术关键——定量浇注、模具选材及寿命和液态模锻装备,给出了突破这三个技术关键的技术路径;随后介绍了大型衬板、大型轮盘件及大型双金属复合钢铁件液态模锻的工艺要点、液锻机特点、关键工艺参数... 首先提出了大型钢铁件液态模锻的三个技术关键——定量浇注、模具选材及寿命和液态模锻装备,给出了突破这三个技术关键的技术路径;随后介绍了大型衬板、大型轮盘件及大型双金属复合钢铁件液态模锻的工艺要点、液锻机特点、关键工艺参数及其技术经济效果。结果表明,称重式自动定量浇注机(车)是钢铁件液态模锻定量浇注的最优选择,自动调节流量的冷却水控制系统和金属型铸钢涂料的使用可以有效调控模具温度,移出工作台的立式多向液态模锻机是大型钢铁件液态模锻的最适宜机型。液态模锻大型钢铁件具有工艺出品率高、组织致密、综合性能优异的突出优势,在耐磨零件、难锻造零件及双金属复合件方面应用前景广阔。 展开更多
关键词 钢铁零件 液态模锻 挤压铸造 工艺装备 应用
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基于通道动态优化与特征重用的多尺度DenseNet脑电情绪识别
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作者 李秋生 苏靖然 《北京联合大学学报》 2026年第1期41-48,共8页
针对现有脑电情绪识别模型浅层特征重用不足及通道关联建模静态化问题,提出一种改进的DenseNet模型。该模型通过引入压缩和激励(SE)模块动态调整前额叶-顶叶关键通道的权重,结合多尺度卷积核(1×1、3×3、5×5),增强δ/θ... 针对现有脑电情绪识别模型浅层特征重用不足及通道关联建模静态化问题,提出一种改进的DenseNet模型。该模型通过引入压缩和激励(SE)模块动态调整前额叶-顶叶关键通道的权重,结合多尺度卷积核(1×1、3×3、5×5),增强δ/θ频段的微分熵特征,提升浅层特征的利用率,并有效抑制噪声。在SEED数据集单被试实验中,该模型以96.73%的准确率显著优于基准模型(DBN:86.08%;DGCNN:90.40%),且在不同通道配置下均表现出鲁棒性。 展开更多
关键词 脑电信号 通道自适应 特征重用 压缩和激励(SE)模块 动态权重
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复杂背景下基于YOLO-insulator模型的绝缘子小目标缺陷检测研究
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作者 董朋林 陈久朋 +2 位作者 王森 伞红军 胡宏伟 《电力科学与技术学报》 北大核心 2026年第1期262-276,共15页
基于计算机视觉的航拍绝缘子缺陷检测方法被广泛应用于电力巡检。针对绝缘子缺陷易受背景复杂、目标尺度较小等因素的影响而导致漏检、误检的问题,提出了一种旨在提高绝缘子缺陷检测精度的绝缘子缺陷检测模型YOLO-insulator。首先,引入... 基于计算机视觉的航拍绝缘子缺陷检测方法被广泛应用于电力巡检。针对绝缘子缺陷易受背景复杂、目标尺度较小等因素的影响而导致漏检、误检的问题,提出了一种旨在提高绝缘子缺陷检测精度的绝缘子缺陷检测模型YOLO-insulator。首先,引入基于通道混洗的重参数化卷积(reparameterized convolution based on channel shuffle-one-shot aggregation, RCS-OSA)替换传统的二维卷积C2f,以增强网络的特征提取能力;其次,在颈部网络使用RCS-OSA模块替换部分的C2f卷积,同时引入挤压激励网络(squeeze and excitation network,SENet),以增强模型对通道间关系的捕捉和整体特征的表达能力;最后,针对多种缺陷区域小导致难以检测的问题,提出小目标检测层方法,该层包含更多的缺陷细节信息,有利于缺陷的检测。在自制绝缘子数据集上进行实验验证的结果表明,相对于基线YOLOv8n,YOLO-insulator模型在查准率、召回率、平均精度均值上都实现了提升,有效提高了模型的综合性能。 展开更多
关键词 绝缘子缺陷检测 复杂背景 注意力机制 挤压激励 小目标检测层
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融合注意力机制和多尺度信息的蛋白质结合位点预测
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作者 鲁帅 尹帅领 +2 位作者 原梦超 吴迪 周清雷 《郑州大学学报(工学版)》 北大核心 2026年第1期66-72,共7页
为了有效解决3D U-Net在蛋白质结合位点预测中存在的噪声干扰和多尺度信息缺乏问题,提出了一种融合注意力机制和多尺度信息的蛋白质结合位点预测模型AMPocket。引入压缩注意力机制,使得模型能够聚焦于关键通道的蛋白质特征,减少无关通... 为了有效解决3D U-Net在蛋白质结合位点预测中存在的噪声干扰和多尺度信息缺乏问题,提出了一种融合注意力机制和多尺度信息的蛋白质结合位点预测模型AMPocket。引入压缩注意力机制,使得模型能够聚焦于关键通道的蛋白质特征,减少无关通道特征对结合位点预测的影响,从而提高分割的精度;在编码器中引入多尺度信息,使模型能够从不同层次捕捉特征,进而获得更加全面和丰富的空间信息。实验结果表明:AMPocket在4个广泛使用的测试集上均取得了优异的预测结果,特别是在SC6K数据集上的DCC成功率和DVO优于所有对比方法,分别为93.04%和55.01%,并且AMPocket具有较少的参数量,表明模型具有更好的预测性能。 展开更多
关键词 蛋白质结合位点预测 3D U-Net 压缩注意力机制 多尺度信息 噪声干扰
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刚柔复合桩承载行为的施工与界面效应:研究现状与展望
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作者 英姿 邓康威 +2 位作者 邓永锋 钱存斌 康立荣 《东南大学学报(自然科学版)》 北大核心 2026年第2期191-201,共11页
软土地基变形大且强度低,工程中常采用桩基复合地基进行地基加固处理,其中刚柔性复合桩复合地基以其承载控沉能力强、成本低的特性而得到广泛应用。本文首先介绍了国内典型刚柔性复合桩的复合方式及施工方法,其次针对其中一种典型刚柔... 软土地基变形大且强度低,工程中常采用桩基复合地基进行地基加固处理,其中刚柔性复合桩复合地基以其承载控沉能力强、成本低的特性而得到广泛应用。本文首先介绍了国内典型刚柔性复合桩的复合方式及施工方法,其次针对其中一种典型刚柔性复合桩——内芯高强度(钢筋)混凝土预制管桩与外芯水泥土搅拌桩复合,从施工效应、多界面效应以及承载特性3个方面进行综述,对比分析国内外研究现状,总结刚柔性复合桩在挤土与挤桩效应、同轴效应、内外界面效应、抗压抗拔承载能力、沉降设计方法等方面当前的研究成果。最后,指出复合桩在挤桩效应、同轴效应以及水平承载力设计等方面的未来研究方向和技术对策,为刚柔性复合桩技术发展和工程应用提供参考和依据。 展开更多
关键词 刚柔性复合桩 承载性能 多界面效应 挤土效应 同轴性
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Higher-Order Fluctuations and SU(1,1) Higher-Order Squeezing in SU(1,1) Generalized Coherent States
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作者 董传华 《Journal of Shanghai University(English Edition)》 CAS 2002年第4期297-302,共6页
The higher order fluctuations in the SU(1,1) generalized coherent states are discussed. The definition of higher order SU(1,1) squeezing is introduced in terms of higher order uncertainty relation. For two poss... The higher order fluctuations in the SU(1,1) generalized coherent states are discussed. The definition of higher order SU(1,1) squeezing is introduced in terms of higher order uncertainty relation. For two possible bosonic realizations of SU(1,1) Lie algebra, the second , fourth and sixth order SU(1,1) squeezing are examined in detail. It is shown that the SU(1,1) generalized coherent states can be squeezed to not only second order, but also fourth and sixth order. Hence, it follows that the higher order squeezing will occur for the fluctuations of the square of amplitude in squeezed vacuum. SU(1,1) higher order squeezing is a kind of non classical property which is independent of second order squeezing. 展开更多
关键词 squeezing higher order squeezing SU(1 1) coherent state SU(1 1) squeezing.
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Amplitude-Nth-power squeezing of PB phase coherent states
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作者 马志民 马爱群 +2 位作者 陈国恒 刘树田 冯立峰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第3期281-285,共5页
PB Phase Coherent States are very important quantum states in quantum optics. In order to investigate the amplitude-Nth-power squeezing of PB Phase Coherent States, we introduce the algebraic properties of the PB phas... PB Phase Coherent States are very important quantum states in quantum optics. In order to investigate the amplitude-Nth-power squeezing of PB Phase Coherent States, we introduce the algebraic properties of the PB phase operator and the PB Phase Coherent States which are constructed by PB phase theory. We applied amplitude-Nth-power squeezing theory to define the Amplitude-Nth-Power Squeezing of PB Phase Coherent States and investigate the characteristic of the amplitude-Nth-power squeezing of PB Phase Coherent States. We obtained surprising results, in that the results were different from the other quantum states. As for |Z〉(PB Phase Coherent State), the results show that when Z is a real number there only exists amplitude-Nth-power squeezing of component; when Z is a complex number, there exists amplitude-Nth-power squeezing of component and component; when Z is a pure imaginary number, if N is odd, then there does not exist amplitude-Nth-power squeezing of component, but there exists amplitude-Nth-power squeezing of component and if N is even, then there exists amplitude-Nth-power squeezing of component, but there does not exist amplitude-Nth-power squeezing of component. 展开更多
关键词 PB phase operator algebraic property PB phase coherent state Nth-power squeezing.
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High-sensitivity phase estimation with a two-mode squeezed coherent state based on a Mach–Zehnder interferometer
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作者 Pengxiang Ruan Jun Liu +3 位作者 Chenlu Li Qingli Jing Mingming Zhang Dong-Xu Chen 《Chinese Physics B》 2026年第2期389-400,共12页
A scheme is proposed based on a Mach-Zehnder interferometer with high phase sensitivity,utilizing a two-mode squeezed coherent state,generated by four-wave mixing,as input.The phase sensitivity of this scheme easily s... A scheme is proposed based on a Mach-Zehnder interferometer with high phase sensitivity,utilizing a two-mode squeezed coherent state,generated by four-wave mixing,as input.The phase sensitivity of this scheme easily surpasses the Heisenberg limit when intensity difference detection is applied.Under phase-matching conditions,the quantum Cramér-Rao bound significantly exceeds the Heisenberg limit.Additionally,the scheme exhibits robustness against photon loss.When compared with the modified SU(1,1)interferometer with two coherent state inputs,this approach demonstrates superior measurement sensitivity,evaluated through various detection methods and the quantum Cramér-Rao bound.This work holds potential applications in quantum metrology. 展开更多
关键词 two-mode squeezed coherent state phase estimation quantum Cramér–Rao bound Heisenberg limit
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增强型可逆神经网络视频隐写网络GAB3D-SEVSN
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作者 徐千惠 钮可 +2 位作者 朱顺哲 石林 李军 《计算机应用》 北大核心 2026年第2期467-474,共8页
针对小样本条件下视频隐写任务中存在的长程运动建模不足和通道冗余导致的过参数化问题,提出一种融合三维全局注意力块(GAB-3D)与压缩激励(SE)通道注意力的增强型视频隐写网络GAB3D-SEVSN。该模型通过优化的GAB-3D模块在三维时空域自适... 针对小样本条件下视频隐写任务中存在的长程运动建模不足和通道冗余导致的过参数化问题,提出一种融合三维全局注意力块(GAB-3D)与压缩激励(SE)通道注意力的增强型视频隐写网络GAB3D-SEVSN。该模型通过优化的GAB-3D模块在三维时空域自适应地聚焦关键运动轨迹,从而增强长程依赖的建模能力;同时,通过在可逆架构中嵌入SE模块实现通道级自适应校准,从而有效抑制冗余参数并缓解过参数化现象。在UCF101数据集(13K视频样本)上的实验结果表明,相较于LF-VSN基线模型,所提模型的峰值信噪比(PSNR)和结构相似度(SSIM)分别提升了0.5 dB和2.06%。消融实验结果验证了各模块的有效性和协同效应。而在高动态场景子集和不同属性视频上的测试结果表明,该模型在PSNR和SSIM上均显著优于基线模型,展现出优异的鲁棒性和泛化能力。 展开更多
关键词 视频隐写 可逆神经网络 压缩激励机制 三维全局注意力机制 通道注意力机制
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基于量子粒子群优化混合神经网络的锂电池SOH估计
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作者 余健辉 杨海东 +2 位作者 徐康康 宋才荣 章润楠 《传感器与微系统》 北大核心 2026年第3期165-171,共7页
准确预测电池的健康状态(SOH)对保障电池长期安全有效运行至关重要。针对锂电池SOH预测研究中面临健康特征提取的有限性、注意力分配的随机性和模型超参数设置的科学性等挑战,提出了量子粒子群优化(QPSO)基于挤压激励注意力增强的混合... 准确预测电池的健康状态(SOH)对保障电池长期安全有效运行至关重要。针对锂电池SOH预测研究中面临健康特征提取的有限性、注意力分配的随机性和模型超参数设置的科学性等挑战,提出了量子粒子群优化(QPSO)基于挤压激励注意力增强的混合神经网络,并应用于锂电池SOH估计。首先,提取多维度健康特征并经过降维得到的主成分部分,输入到挤压激励注意力增强的卷积神经网络(CNN)以充分提取特征。随后,使用长短期记忆(LSTM)神经网络充分提取长时依赖关系。最后,使用量子粒子群进行超参数寻优,以达到全局最优。广泛的实验验证和对比研究表明:所提方法具有较优预测性能,对比最优基线模型,预测误差均方根误差(RMSE)下降0.29%,决定系数(R^(2))上升0.61%。因此,所提方法有望成为电池健康管理的有效信息指导。 展开更多
关键词 健康状态预测 混合神经网络 量子粒子群优化 挤压激励注意力 多维度健康特征
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复杂铝合金薄壁壳体挤压铸造成形工艺设计及优化
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作者 邱昱翔 苏小平 《特种铸造及有色合金》 北大核心 2026年第2期177-182,共6页
以某复杂铝合金薄壁壳体为对象,针对较常出现的缩松、缩孔缺陷及二次枝晶臂间距等问题优化其挤压铸造工艺参数。通过对浇注系统、冷却系统进行初步优化,并采取田口试验设计与信噪比分析方法,探究浇注温度、冲头速度及模具预热温度对挤... 以某复杂铝合金薄壁壳体为对象,针对较常出现的缩松、缩孔缺陷及二次枝晶臂间距等问题优化其挤压铸造工艺参数。通过对浇注系统、冷却系统进行初步优化,并采取田口试验设计与信噪比分析方法,探究浇注温度、冲头速度及模具预热温度对挤压铸件的缩松缩孔缺陷及二次枝晶臂间距的影响。基于模拟分析结果,通过多组工艺参数对比确定了优化方案,即浇注温度为700℃,冲头速度为0.04 m/s,模具预热温度为220℃,相较原始工艺方案,采用优化方案后铸件的缩松缩孔体积减少了89.9%,最大二次枝晶间距减小了10.6%,满足工艺优化的预期要求。 展开更多
关键词 铝合金薄壁壳体 挤压铸造 田口试验法 数值模拟 工艺优化
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改进Murphy证据理论的水下桩墩病害声呐图像融合检测
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作者 王圣贤 姜绍飞 +1 位作者 王威 苏振恒 《福州大学学报(自然科学版)》 北大核心 2026年第1期51-58,共8页
针对水下桩墩结构病害检测中存在的声呐图像分辨率低、噪声干扰显著和单一数据源精度不足的问题,提出一种改进Murphy证据理论的多源声呐图像融合检测方法.首先,构建基于Darknet-53和ResNet-50的互补YOLOv3模型,提供多样化的证据体以增... 针对水下桩墩结构病害检测中存在的声呐图像分辨率低、噪声干扰显著和单一数据源精度不足的问题,提出一种改进Murphy证据理论的多源声呐图像融合检测方法.首先,构建基于Darknet-53和ResNet-50的互补YOLOv3模型,提供多样化的证据体以增强信息表征.其次,为两个互补模型嵌入压缩和激励网络(SE)注意力机制,增强模型对病害区域的检测性能.最后,改进Murphy证据理论实现多源数据融合,提升方法的精度与鲁棒性.实验结果表明,所提方法在常见病害识别中查准率、查全率和平均精度均值均高于93.7%,显著优于其他模型.这表明改进Murphy证据理论融合深度学习与多源数据,有效提升了声呐图像病害检测精度及环境适应性,为复杂水下工程病害检测提供创新的解决方案. 展开更多
关键词 水下桩墩 病害检测 声呐图像 Murphy证据理论 激励网络(SE)注意力机制 特征提取
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