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SO(3,2) Structure and Distributions of Two-Component Bose-Einstein Condensates with Lower Excitations

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Communications in Theoretical Physics 2003年第1期39卷 31-38页

作者： ZHANGHong－biao DepartmentofPhysics NortheastNormalUniversityChangchun130024China；TheoreticvalPhysicsDivisionNank

The eigenstates describing two-component Bose–Einstein condensates (BEC) with weakly excitations have been found, by using the SO(3,2) algebraic mean-field approximation. We show that the two-component modified BEC (see Eq.(26)) possesses uniquely super-Poissonian distribution in a fixed magnetic field along direction. The distribution will be uncertain, if B = 0.

关键词： algebraic mean-field approximation SO(3,2)-coherent state super-Poissonian distribution

Quantum State Engineering by Superpositions of Coherent States along a Straight Line in Cavity Quantum Electrodynamics

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Chinese Physics Letters 2001年第8期18卷 1072-1073页

作者： ZHENG Shi-biao Department of Electronic Science and Applied Physics Fuzhou UniversityFuzhou 350002

A scheme is proposed for generating the superpositions of several coherent states in a cavity field with dispersive cavity quantum electrodynamics(QED).In the scheme,a sequence of atoms interact dispersively with the cavity field,connected with a microwave source,and is manipulated by classical fields,followed by state-selective *** this way,the cavity field is collapsed onto a superposition of several coherent states along a straight line with controllable *** scheme provides the possibility for quantum state engineering via coherent-state superpositions in cavity QED for the first time.

关键词： superposition coherent scheme

有限元分析不同程度冈上肌断裂对肩关节应力的影响

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中国组织工程研究 2025年第9期29卷 1768-1774页

作者：徐彪路坦姜亚琼阴玉娇新乡医学院第一附属医院河南省卫辉市453100

背景:目前研究冈上肌的精细解剖及各亚区域的生物力学表现的实验较多,但是对冈上肌不同区域的损伤所带来的肩关节应力的影响鲜有耳闻。很有必要了解不同区域的冈上肌损伤对关节软骨及关节盂的应力大小及分布的影响,从而给临床诊治提供... 详细信息

背景:目前研究冈上肌的精细解剖及各亚区域的生物力学表现的实验较多,但是对冈上肌不同区域的损伤所带来的肩关节应力的影响鲜有耳闻。很有必要了解不同区域的冈上肌损伤对关节软骨及关节盂的应力大小及分布的影响,从而给临床诊治提供一些理论支持。目的:探究在三维有限元软件中模拟不同程度的冈上肌断裂对肱骨软骨面、关节盂唇及关节盂软骨关节面的最大应力值。方法:获取正常健康的肩关节CT或MRI导入Mimics、Geomagic进行提取模型,再通过Soildworks对模型构建,再对各个模型的冈上肌进行不同程度的损伤,模拟出不同区域的断裂。最后导入机械软件Ansys,进行三维有限元生物力学分析,计算肱骨软骨面、关节盂唇及关节盂软骨关节面的应力数值。结果与结论:①随着冈上肌损伤程度的加重肩关节软骨面及盂唇的应力也会增加;②冈上肌前部在各区域中最为重要;③不同程度的冈上肌断裂对肩关节盂唇面的软骨应力大小有影响,而应力的分布区域无明显改变;④提示肩关节水平外展起始时,前部发挥着重要的作用,其次为后部深区;当冈上肌前部损伤时肩关节软组织应力增加明显,还容易引起关节盂唇顶部及关节盂软骨前下方的损伤。

关键词：冈上肌肩关节关节盂生物力学有限元分析

Possibility of measuring spin precession of the nearest supermassive black hole by using S stars

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Research in Astronomy and Astrophysics 2014年第11期14卷 1415-1422页

作者： Wen-biao Han Shanghai Astronomical Observatory

The supermassive black hole （SMBH） with a mass of 4 million M⊙ inside the radio source Sgr A＊ in our Galactic center is the nearest SMBH. Once S stars with a shorter period are observed, relativistic precessions especially the Lense-Thirring effect can be measured by astronomical observations at the 10 ~tas level in the future. An interesting but so far unaddressed problem is that the SMBH not only has spin but also spin precession like similar objects. We study the effect of such spin precession on the orbital precessions of orbiting stars. Our results show that the spin precession can produce a periodic oscillation in the precession of the star＇s orbital plane, but has no obvious effect on the periapse shift. For stars with an orbital period of O（0.1） yr or less, such visible oscillations occur when the SMBH＇s spin-precession period ranges from about a few tens of years to hundreds of years. The period of oscillation is the same as the one of the spin precession. In principle, the precession of this oscillating orbital plane can be observed and then the spin and spin precession of the nearest SMBH can be determined.

关键词： black hole physics -- Galaxy center -- relativity

基于改进DeblurGAN-v2的运动模糊农作物害虫图像复原方法

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光电子·激光 2025年第1期36卷 46-52页

作者：赵辉黄镖王红君岳有军天津理工大学电气工程与自动化学院天津市复杂系统控制理论与应用重点实验室

为对巡检机器人在巡检过程中产生的运动模糊图像进行高效精准识别，提出了一种基于改进DeblurGAN-v2的运动模糊农作物害虫图像复原方法。为有效提取图像重要特征，该方法将通道注意力(channel attention, CA)机制集成到DeblurGAN-v2主... 详细信息

为对巡检机器人在巡检过程中产生的运动模糊图像进行高效精准识别，提出了一种基于改进DeblurGAN-v2的运动模糊农作物害虫图像复原方法。为有效提取图像重要特征，该方法将通道注意力(channel attention, CA)机制集成到DeblurGAN-v2主干网格中，使模型更加关注细节特征，提高对运动模糊图像的复原能力；此外，在原模型特征提取网络顶层引入空间金字塔池化(spatial pryamid pooling, SPP)缓解图像多尺度变化造成对图像复原的负面影响，提高模型对图像复原的性能。基于实际农田环境建立的数据集所做的实验结果表明，改进后算法的PSNR、SSIM指标分别为26.281 8 dB、0.947 3,较原模型提升了8、7.2个百分点。与其他主流模型的对比实验结果表明，本文方法对模糊图像的实际复原效果更优，对解决运动模糊农作物害虫的图像复原问题具有实际应用价值。

关键词：运动模糊深度学习图像复原 DeblurGAN-v2 通道注意力(CA)机制空间金字塔池化(SPP)模块

A thermodynamic-based model for modeling thermo-elastoplastic behaviors of saturated clayey soils considering bound water dehydration

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第6期15卷 1535-1546页

作者： Mohammadhossein Sojoudi biao Li Department of Building Civil and Environmental EngineeringConcordia UniversityMontrealQuebecCanada

The non-isothermal deformation of soft mudrocks or clay soils is one of the most critical issues in energy and environmental related ***-related geomaterials hold complex microstructure and mineral composition,which brings difficulty in investigating their thermo-mechanical *** studies pay little attention to the difference between a thermal plastic strain and the strain from clay *** this study,a new constitutive model is proposed for describing the thermoelastoplastic behaviors of clayey soils under water-saturated *** effect of temperature variation and mechanical loading on elastoplastic strains and dehydration are *** thermodynamics laws and the unconventional plasticity are applied to quantify the thermo-mechanical *** irreversible strain is captured by using Cam-Clay plasticity and subloading yield surface *** dehydration strain is described by utilizing a novel method based on generalized thermodynamics approach and Helmholtz free energy *** internal variables,and the first and second laws of thermodynamics are applied in the *** hardening rule is established by implementing the laws of physical conservation,energy dissipation,and plastic *** proposed model is validated using specially designed thermal consolidation tests on laboratory prepared heavily consolidated clayey soils and some published data of clayey soils with different geological origins.

关键词： Thermo-mechanical process Subloading yield surface Energy methods Clay-bound water Dehydration

Analysis of the Vertical and Lateral Interactions in a Multisheet Array of InAs/GaAs Quantum Dots

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Journal of Materials Science & Technology 2009年第5期25卷 677-680页

作者： Hui She biao Wang School of Engineering Sun Yat-Sen University Guangzhou 510275 China Guangdong Provincial Academy of Building Research Guangzhou 510500 China

The vertical and lateral interactions in a multisheet array of InAs/GaAs quantum dots are analyzed by finite element method （FEM）. It is shown that due to the effects of vertical interaction, nucleation prefers to happen above buried quantum dots （QDs）. Meanwhile, the effects of lateral interaction adjust the spacing of lateral neighboring QDs. The vertical coupling becomes strong with deceasing GaAs spacer height and increasing number of buried layers, while the lateral coupling becomes strong with increasing InAs wetting layer thickness. The phenomenon that, after successive layers, the spacing and size of QDs islands become progressively more uniform is explained according to the minimum potential energy theory.

关键词： Quantum dots Vertical and lateral interactions Finite element analysis

STABLE AND ROBUST RECOVERY OF APPROXIMATELY k-SPARSE SIGNALS WITH PARTIAL SUPPORT INFORMATION IN NOISE SETTINGS VIA WEIGHTED ℓ_(p)(0

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Journal of Computational Mathematics 2023年第6期41卷 1137-1170页

作者： biao Du Anhua Wan School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China

In the existing work,the recovery of strictly k-sparse signals with partial support information was derived in theℓ2 bounded noise *** this paper,the recovery of approximately k-sparse signals with partial support inf... 详细信息

关键词： Signal recovery weightedℓp minimization Approximately k-sparse signal Noise setting Reconstruction error bound Restricted isometry property

Solving forward and inverse problems of the nonlinear Schrodinger equation with the generalized PT-symmetric Scarf-Ⅱpotential via PINN deep learning

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Communications in Theoretical Physics 2021年第12期73卷 1-13页

作者： Jiaheng Li biao Li School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

In this paper,based on physics-informed neural networks(PINNs),a good deep learning neural network framework that can be used to effectively solve the nonlinear evolution partial differential equations(PDEs)and other types of nonlinear physical models,we study the nonlinear Schrodinger equation(NLSE)with the generalized PT-symmetric Scarf-Ⅱpotential,which is an important physical model in many fields of nonlinear ***,we choose three different initial values and the same Dinchlet boundaiy conditions to solve the NLSE with the generalized PT-symmetric Scarf-Ⅱpotential via the PINN deep learning method,and the obtained results are compared with ttose denved by the toditional numencal ***,we mvestigate effect of two factors(optimization steps and activation functions)on the performance of the PINN deep learning method in the NLSE with the generalized PT-symmetric Scarf-Ⅱ***,the data-driven coefficient discovery of the generalized PT-symmetric Scarf-Ⅱpotential or the dispersion and nonlinear items of the NLSE with the generalized PT-symmetric Scarf-Ⅱpotential can be approximately ascertained by using the PINN deep learning *** results may be meaningful for further investigation of the nonlinear Schrodmger equation with the generalized PT-symmetric Scarf-Ⅱpotential in the deep learning.

关键词： nonlinear Schrodinger equation generalized PT-symmetric scarf-Ⅱpotential physics-informed neural networks deep learning initial value and dirichlet boundary conditions data-driven coefficient discovery