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Quantum optical interferometry via general photon-subtracted two-mode squeezed states

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Chinese Physics B 2019年第9期28卷 258-264页

作者： Li-Li Hou Jian-Zhong Xue yong-xing sui Shuai Wang School of Mathematics and Physics Jiangsu University of Technology

We investigate the sensitivity of phase estimation in a Mach-Zehnder interferometer with photon-subtracted twomode squeezed vacuum *** results show that, for given initial squeezing parameter, both symmetric and asymmetric photon subtractions can further improve the quantum Cramér-Rao bound(i.e., the ultimate phase sensitivity), especially for single-mode photon *** the other hand, the quantum Cramér-Rao bound can be reached by parity detection for symmetric photon-subtracted two-mode squeezed vacuum states at particular values of the phase shift, but it is not valid for asymmetric photon-subtracted two-mode squeezed vacuum *** addition, compared with the two-mode squeezed vacuum state, the phase sensitivity via parity detection with asymmetric photon-subtracted two-mode squeezed vacuum states will be getting ***, parity detection may not always be the optimal detection scheme for nonclassical states of light when they are considered as the interferometer states.

关键词： quantum optics phase sensitivity quantum metrology

Robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 154-168页

作者： Fei Weng Guijun Bi Youxiang Chew Shang sui Chaolin Tan Zhenglin Du Jinlong Su Fern Lan Ng Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong Engineering&Technology Research Center for Superhard MaterialSchool of Materials Science and EngineeringShandong UniversityJinan 250061China Institute of Intelligent Manufacturing Guangdong Academy of SciencesGuangzhou 510095China Singapore Institute of Manufacturing Technology 5 Cleantech Loop636732Singapore

The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for LAAM_(p) and LAAM_(w),*** the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire *** characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α *** mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and *** mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material Specifications(AMS 6932)even without post heat *** fracture occurred within the interfacial area,further suggesting the robust *** findings of this study highlighted the feasibility of combining LAAM_(p) and LAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition.

关键词： laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： xinguang Zhu Chenxi Ding Zhe sui Hong Su Xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

MDCFS: few-shot object detection with multilevel decoupled classifiers

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Optoelectronics Letters 2025年

作者： LI Chuanhui ZHOU Mian FENG Zhikun sui Zezhou GAO Zhan School of Computer Science and Engineering， Tianjin University of Technology

Few-shot object detection poses unique challenges as it requires effectively learning novel classes with limited labeled data. Current approaches often suffer from biases towards base classes during fine-tuning， leading to suboptimal performance on detecting novel classes. Additionally， in complex scenes， the confusion between foreground and background objects further affects the accuracy and robustness of the model. To address these issues， we propose the Multilevel Decoupling Classification Few-Shot Algorithm (MDCFS). we decouple the standard classifier into a parallel foreground classifier and a background classifier in the Few-Shot Object Detection (FSOD) setting. This decoupling enables the independent separation of positive samples from noisy negative samples， alleviating the foreground-background confusion problem commonly encountered in few-shot detectors. For Generalized Few-Shot Object Detection (G-FSOD)， where the few-shot dataset contains base classes， we further decouple the foreground classification head into a base class classification head and a novel class classification head. To ensure balance， we assign more weight to the novel class classification head， effectively addressing the bias towards base classes. Furthermore， we optimize the initial weights of the few-shot fine-tuning stage， significantly reducing training time and mitigating catastrophic forgetting in G-FSOD. Additionally， we incorporate metric learning into our model with minimal cost. Experimental results demonstrate the effectiveness of our approach. Compared to state-of-the-art few-shot object detection methods based on fine-tuning， MDCFS achieves performance improvements of up to 6.3% on the PASCAL VOC dataset and 1.5% on the COCO dataset.

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Skyrmion-(non)crystal structure stabilized by dipolar interaction

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Rare Metals 2022年第9期41卷 3160-3169页

作者： Ming-Xiu sui yong Hu Department of Physics College of SciencesNortheastern UniversityShenyang110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China

We report a numerical study on the role of longrange dipolar interaction played on the creation and stabilization of skyrmion-(non)crystal structure in chiral ferromagnetic thin films without any anisotropies,based on a Monte-Carlo simulation *** the increase of external magnetic field,the microscopic spin configuration is transformed from a spin-spiral stripe or labyrinth structure,depending on the strength of dipolar interaction,into a skyrmion-(non)crystal structure,and then into a skyrmiongas structure,and finally into a ferromagnetic ***,with the increase of dipolar interaction,the skyrmion-crystal structure evolves from a triangular arrangement into a square arrangement with the change of skyrmion shape from circle to *** larger dipolar interactions,the skyrmion-crystal structure loses the regular arrangements and the skyrmions,remaining topological,exhibit different shapes and sizes and squeeze with each other,whose distributions are analogous to a non-crystal ***,different skyrmion-(non)crystal structures are stabilized in different ranges of dipolar interactions,which further promotes the applications of skyrmions as non-volatile information carriers.

关键词： Chiral ferromagnetic thin film Skyrmion(non)crystal structure Interfacial Dzyaloshinskii-Moriya interaction Dipolar interaction Monte-Carlo simulation

High-temperature creep constitutional model of Q460E steel and effect of creep on bulging deformation of continuous casting slab

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Journal of Iron and Steel Research International 2018年第11期25卷 1123-1130页

作者： Long Guo Yun-huan sui xing-zhong Zhang National Engineering Research Centre for Equipment and Technology of Cold Strip Rolling Yanshan University Qinhuangdao 066004HebeiChina Hesteel Group Tangsteel Company Tangshan 063016HebeiChina

Mechanical properties and creep behavior of Q460E continuous casting slab were studied by means of uniaxial tensile tests on a Gleeble-3800 thermomechanical simulator from 1000 to 1100 ℃.The high-temperature creep constitutional equation was derived based on experimental *** parameters in the equation were calculated by using the regression analysis inverse-estimation *** experimental curves in the primary and secondary creep stages are fitted well.A three-dimensional elastic-plastic and creep finite element model was proposed in order to investigate the bulging deformation of slab and the bulging deformation at the beginning position of bending segment on the slab continuous casting machine was computed *** results indicate that the maximum bulging deformation appears at the geometric center of the *** maximum value of the bulging deformation obtained by the elastic-plastic analysis is 1.301 *** the creep effect,the deformation increases to 1.827 mm which is about 1.4 times the value obtained by the elastic-plastic *** calculation of buleing deformation usin2 the elastic-plastic creed model is more reliable and/iccurate.

关键词： Steel mechanical property High temperature creep behavior Creep constitutional equation Bulging deformation Steel continuous casting

Topology Optimization for Design of Hybrid Lattice Structures with Multiple Microstructure Configurations

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Acta Mechanica Solida Sinica 2022年第3期35卷 367-383页

作者： Nan Wei Hongling Ye xing Zhang Jicheng Li Yunkang sui Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China College of Mechanical and Architectural Engineering Taishan UniversityTaian 271000China

Hybrid lattice structures consisting of multiple microstructures have drawn much attention due to their excellent performance and extraordinary *** work puts forward a novel design scheme of lightweight hybrid lattice structures based on independent continuous mapping(ICM)***,the effective elastic properties of various microstructure configurations serve as a bridge between the macrostructure and the multiple microstructures by the homogenization ***,a concurrent topology optimization model for seeking optimized macroscale topology and the specified microstructures is established and solved by a generalized multi-material interpolation formulation and sensitivity ***,several numerical examples show that hybrid lattice structures with different anisotropic configurations accomplish a better lightweight effect than those with various orthogonal configurations,which verifies the feasibility of the presented ***,anisotropic configurations are more conducive to the sufficient utilization of constitutive *** proposed scheme supplies a reference for the design of hybrid lattice structures and extends the application field of the ICM method.

关键词： Topology optimization Hybrid lattice structures Multiple microstructure configurations Anisotropic ICM method

Benchmark solutions of large-strain cavity contraction for deep tunnel convergence in geomaterials

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第3期12卷 596-607页

作者： Pin-Qiang Mo yong Fang Hai-sui Yu State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou221116China Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu610031China School of Civil Engineering University of LeedsLeedsLS29JTUK

To provide precise prediction of tunnelling-induced deformation of the surrounding geomaterials,a framework for derivation of rigorous large-strain solutions of unified spherical and cylindrical cavity contraction is presented for description of confinement-convergence responses for deep tunnels in *** the tunnelling-induced large deformation,logarithmic strains are adopted for cavity contraction analyses in linearly elastic,non-associated Mohr-Coulomb,and brittle Hoek-Brown *** with approximate solutions,the approximation error indicates the importance of release of small-strain restrictions for estimating tunnel convergence profiles,especially in terms of the scenarios with high stress condition and stiffness degradation under large *** ground reaction curve is therefore predicted to describe the volume loss and stress relaxation around the tunnel *** stiffness of circular lining is calculated from the geometry and equivalent modulus of the supporting structure,and a lining installation factor is thus introduced to indicate the time of lining installation based on the prediction of spherical cavity contraction around the tunnel opening *** study also provides a general approach for solutions using other sophisticated geomaterial models,and serves as benchmarks for analytical developments in consideration of nonlinear large-deformation behaviour and for numerical analyses of underground excavation.

关键词： Convergence-confinement method(CCM) Cavity contraction analysis Tunnel convergence

Microstructure and Optical Properties of Ti_(54.5)Ni_(45.5) Nanocrystalline Thin Film

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Acta Metallurgica Sinica(English Letters) 2017年第12期30卷 1231-1235页

作者： Xin Zhang Jie-He sui yong-Chao Lei Wei Cai School of Materials Science and Engineering Tianjin University of Technology National Key Laboratory Precision Hot Processing of Metals Harbin Institute of Technology

Nanocrystalline Ti54.5Ni45.5 thin film was prepared by magnetron sputtering followed by rapid thermal annealing. The film displayed martensite structure and （001） compound twin substructure, and the transformation temperatures Ms and As are 313 and 365 K, respectively. The reflectivity for the wavelength from 200 to 800 nm at 298 and 393 K was investigated, and the results showed that the optical reflectivity contrast between martensite and austensite at 780, 650, 514 and 405 nm was 105.64, 170.83, 112.22 and 149.92%, respectively, which were larger than those of other reported optical recording materials.

关键词： Ti–Ni thin films Sputtering Shape memory alloys Optical properties Microstructure