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Journal of Zhejiang university-Science A(Applied physics & Engineering) 2007年第9期8卷 1366-1372页

作者： ZHANG Li-mei chen Wu-jun DONG Shi-lin Space Structures Research Center Shanghai Jiao Tong University Shanghai 200030 China

The cable-strut structural system is statically and kinematically indeterminate. The initial pre-stress is a key factor for determining the shape and load carrying capacity. A new numerical algorithm is presented herein for the initial pre-stress finding procedure of complete cable-strut assembly. This method is based on the linear adjustment theory and does not take into account the material behavior. By using this method,the initial pre-stress of the multi self-stress modes can be found easily and the cal-culation process is simplified and efficient also. Finally,the initial pre-stress and structural performances of a particular Levy cable dome are analyzed comprehensively. The algorithm has proven to be efficient and correct,and the numerical results are valuable for practical design of Levy cable dome.

关键词： Linear adjustment theory Cable-strut structure Initial pre-stress Levy cable dome Structural performances analysis

基于交叉注意力的CT与MRI直肠癌病灶分割方法

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中国医学物理学杂志 2024年第8期41卷 953-959页

作者：邓杰夫奚峥皓黄陈刘翔上海工程技术大学电子电气工程学院上海201620 上海交通大学附属第一人民医院普外科上海200080

针对直肠癌辅助诊断过程中部分医学图像分割模型只适用于单一模态图像的局限性,提出一种基于交叉注意力机制并同时适用于CT与MRI两种模态的医学图像分割方法。首先,针对CT与MRI两种图像特征表示不同,提出一种交叉注意力机制统一两类图... 详细信息

针对直肠癌辅助诊断过程中部分医学图像分割模型只适用于单一模态图像的局限性,提出一种基于交叉注意力机制并同时适用于CT与MRI两种模态的医学图像分割方法。首先,针对CT与MRI两种图像特征表示不同,提出一种交叉注意力机制统一两类图像的特征表示;其次,针对直肠癌图像病灶区域较小的特点,提出三支路的改进SwinTransformer分割网络,并将交叉注意力机制加入其中,使模型对两种图像都能进行病灶区域的分割;最后,使用该方法在直肠癌患者的CT与MRI影像数据进行验证,与ADDA、CycleGAN和SIFA方法相比,在CT图像上的准确率分别提高2.94%、3.05%、0.71%,在MRI图像上的准确率分别提高了3.31%、4.55%、1.76%。实验结果表明该方法对于两类图像具有更好的分割性能。

关键词：直肠癌语义分割交叉注意力 Transformer

Hexagonally ordered microbowl arrays decorated with ultrathin CuInS_(2) nanosheets for enhanced photoelectrochemical performance

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Journal of Energy Chemistry 2020年第12期29卷 134-142页

作者： Ming Li Le chen Yanjie Su Huan Yin Kexiang Hu State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China School of Electronic Engineering and Automation Guilin University of Electronic TechnologyKey Laboratory of Optoelectronic Information Processing of Guangxi Colleges and Uniy/ersitiesGuilin 541004GuangxiChina Key Laboratory for Thin Film and Microfabrication of the Ministry of Education Department of Micro/Nano ElectronicsSchool of ElectronicsInformation and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China National and Local Joint Engineering Laboratory of Internet Technology on Mine School of Information and Control EngineeringChina University of Mining and TechnologyXuzhou 221008JiangsuChina School of physics and Telecommunication Engineering Guangxi Colleges and Universities Key Lab of Complex System Optimization and Big Data ProcessingYulin Normal UniversityYulin 537400GuangxiChina

This paper demonstrates the design and fabrication of three-dimensional(3 D) hexagonally ordered microbowl arrays(MBAs) decorated with Cu In S2 nanosheets for enhanced photoelectrochemical(PEC) performance. The 3 D MBAs are fabricated by a micro-fabrication technique. The ultrathin CuInS2 nanosheets are grown on the 3 D electrodes by solvothermal transformation of Cu film. The photocurrent density of 3 D photocathode(CuInS2@MBAs) is about two times higher than that of the planar counterpart(CuInS2@Planar). The improved PEC performance can be ascribed to the elevated light trapping ability and the increased surface area for loading photocatalysts. In addition, CdS quantum dots as cocatalysts are modified onto the Cu In S2 nanosheets to further enhance the PEC activity because the formed p-n heterojunction can accelerate the separation of photogenerated carriers. As a result, the 3 D photocathode of CuInS2/CdS@MBAs shows an optimal incident photon to current efficiency of 10% at the wavelength of400 nm. It is believed that this work can be generalized to design other hierarchical 3 D photoelectrodes for improved solar water splitting.

关键词： Microbowl array CuInS_(2) Nanosheet Photocathode Photoelectrochemical performance

Einstein-Podolsky-Rosen Entanglement and Quantum Nonlocality for an Electron in a Uniform Magnetic Field

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Chinese physics Letters 2000年第5期17卷 316-318页

作者： FAN Hong-Yi chen Zeng-Bing department of Applied physics Shanghai Jiao Tong UniversityShanghai 200030 department of Material Science and Engineering University of Science and Technology of ChinaHefei 230026

Ws show that there exists the precise Einstein-Podolsky-Rosen entanglement for an electron in a uniform magnetic ***,the x-and y-coordinates of the electron as well as the corresponding canonical momenta px and Pv become sharply correlated,which is a novel fact unnoticed *** a harmonic potential is added to the system,the original vacuum state of the system becomes a squeezed vacuum state,whose quantum nonlocality is then demonstrated.

关键词： Einstein vacuum Uniform

Density Functional Theory Studies of Magnetically Confined Fermi Gas

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Chinese physics Letters 2001年第1期18卷 33-35页

作者： chen Yu-Jun MA Hong-Ru department of Applied physics Shanghai Jiao Tong UniversityShanghai 200240

A theory is developed for magnetically confined Fermi gas at a low temperature based on the density functional *** theory is illustrated by the numerical calculation of the density distributions of Fermi atoms 40K with parameters according to DeMarco and Jin's experiment[Science,285(1999)1703].Our results are in close agreement with the *** check the theory,we also performed calculations using our theory at a high temperature,which compared very well to the results of the classical limit.

关键词： experiment theory Fermi

A Consensus-Based Global Optimization Method with Adaptive Momentum Estimation

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Communications in Computational physics 2022年第4期31卷 1296-1316页

作者： Jingrun chen Shi Jin Liyao Lyu School of Mathematical Sciences University of Science and Technology of ChinaHefeiAnhui 230026China Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhouJiangsu 215123China School of Mathematical Sciences Institute of Natural SciencesMOE-LSCShanghai Jiao Tong UniversityShanghai200240China department of Computational Mathematics Scienceand EngineeringMichigan State UniversityEast LansingMI48824USA

Objective functions in large-scalemachine-learning and artificial intelligence applications often live in high dimensions with strong non-convexity and massive local ***-based methods,such as the stochastic gradient method and Adam[15],and gradient-freemethods,such as the consensus-based optimization(CBO)method,can be employed to find *** this work,based on the CBO method and Adam,we propose a consensus-based global optimization method with adaptive momentum estimation(Adam-CBO).Advantages of the Adam-CBO method include:It is capable of finding global minima of non-convex objective functions with high success rates and low *** is verified by finding the global minimizer of the 1000 dimensional Rastrigin function with 100%success rate at a cost only growing linearly with respect to the *** can handle non-differentiable activation functions and thus approximate lowregularity functions with better *** is confirmed by solving a machine learning task for partial differential equations with low-regularity solutions where the Adam-CBO method provides better results than *** is robust in the sense that its convergence is insensitive to the learning rate by a linear stability *** is confirmed by finding theminimizer of a quadratic function.

关键词： Consensus-based optimization global optimization machine learning curse of dimensionality

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利用掺杂层研究磁化靶中的能斯特效应

强激光与粒子束 2024年第9期36卷 169-174页

作者：陈诗佳张华周沧涛卓红斌吴福源 Rafael Ramis 深圳大学应用技术学院广东深圳518060 深圳技术大学深圳市超强激光与先进材料技术重点实验室超强激光应用技术研究中心工程物理学院广东深圳518118 上海交通大学物理与天文学院上海200240 马德里理工大学航空航天学院马德里E-28040

双层磁化套筒靶在内层采用高原子序数(Z)材料,减少了因能斯特效应导致的磁通损失并降低点火要求,为磁化靶聚变提供了一种备选方案。然而,添加高Z材料也可能增加由于物质混合而产生的辐射损失。通过在金属套筒中使用带有塑料掺杂的锗作为... 详细信息

双层磁化套筒靶在内层采用高原子序数(Z)材料,减少了因能斯特效应导致的磁通损失并降低点火要求,为磁化靶聚变提供了一种备选方案。然而,添加高Z材料也可能增加由于物质混合而产生的辐射损失。通过在金属套筒中使用带有塑料掺杂的锗作为高Z替代物,初步分析了磁场能斯特输运和物质混合对磁化套筒惯性聚变的影响。与单层套筒相比,双层套筒靶展示出温度和磁通的显著增加,从而使聚变产额提高了154%。将碳氢掺杂剂添加到最内层的锗中,模拟了物质混合对聚变产额的影响。研究结果表明,锗与CH混合,保持较低的混合比例,能够显著提高聚变产额。

关键词：双层套筒磁化靶聚变能斯特效应掺杂物质混合

电弧增材制造焊丝熔化及熔滴过渡过程建模与仿真研究

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电加工与模具 2024年第3期 48-53页

作者：陈世雄姚继开范立想唐伟东康小明长沙理工大学汽车与机械工程学院湖南长沙410114 省部共建精密电子制造技术与装备国家重点实验室广东广州510006 上海交通大学机械与动力工程学院上海200241

基于动网格和多物理场耦合技术,建立了焊丝熔化和熔滴过渡的热流耦合数学模型。研究了焊丝熔化形成熔滴、熔滴与基板的接触和铺展、熔融金属桥形成和拉断过程。分析了熔滴在送丝过程中的温度变化、熔滴和熔池的速度变化、熔滴传质过程... 详细信息

基于动网格和多物理场耦合技术,建立了焊丝熔化和熔滴过渡的热流耦合数学模型。研究了焊丝熔化形成熔滴、熔滴与基板的接触和铺展、熔融金属桥形成和拉断过程。分析了熔滴在送丝过程中的温度变化、熔滴和熔池的速度变化、熔滴传质过程中的体积变化。结果表明,熔滴尺寸、形状与实验结果可较好吻合,最终转移至基板表面熔融铝的体积约占熔滴总体积的80%。

关键词：电弧增材制造焊丝熔化熔滴过渡仿真分析

Reconstruction of quantum channel via convex optimization

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Science Bulletin 2020年第4期65卷 286-292页

作者： Xuan-Lun Huang Jun Gao Zhi-Qiang jiao Zeng-Quan Yan Zhe-Yong Zhang Dan-Yang chen Xi Zhang Ling Ji Xian-Min Jin Center for Integrated Quantum Information Technologies(IQIT) School of Physics and Astronomy and State Key Laboratory of Advanced Optical Communication Systems and NetworksShanghai Jiao Tong UniversityShanghai 200240China CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum physics University of Science and Technology of ChinaHefei 230026China

Quantum process tomography is often used to completely characterize an unknown quantum ***, it may lead to an unphysical process matrix, which will cause the loss of information with respect to the tomography result. Convex optimization, widely used in machine learning, is able to generate a global optimum that best fits the raw data while keeping the process tomography in a legitimate region. Only by correctly revealing the original action of the process can we seek deeper into its properties like its phase transition and its Hamiltonian. Here, we reconstruct the seawater channel using convex optimization and further test it on the seven fundamental gates. We compare our method to the standard-inversion and norm-optimization approaches using the cost function value and our proposed state deviation. The advantages convince that our method enables a more precise and robust estimation of the elements of the process matrix with less demands on preliminary resources. In addition, we examine on a set of non-unitary channels and the reconstructions reach up to 99:5% accuracy. Our method offers a more universal tool for further analyses on the components of the quantum channels and we believe that the crossover between quantum process tomography and convex optimization may help us move forward to machine learning of quantum channels.

关键词： Quantum information Quantum process tomography Convex optimization Quantum channel

Rotational structure of the odd-proton nuclide ^(171)Tm:A projected shell model study

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Science china(physics,Mechanics & Astronomy) 2015年第5期58卷 76-81页

作者： LIU YanXin chen FangQi YU ShaoYing SUN Yang School of Science Huzhou University china Institute of Atomic Energy department of physics and Astronomy Shanghai Jiao Tong University

Deformed odd-mass nuclei are ideal examples where the interplay between single-particle and collective degrees of freedom can be studied. Inspired by the recent experimental high-spin data in the odd-proton nuclide 171 Tm, we perform projected shell model(PSM) calculations to investigate structure of the ground band and other bands based on isomeric states. In addi- tion to the usual quadrupole-quadrupole force in the Hamiltonian, we employ the hexadecapole-hexadecapole(HH) interac- tion, in a self-consistent way with the hexadecapole deformation of the deformed basis. It is found that the known experi- mental data can be well described by the PSM calculation. The effect of the HH force on the quasiparticle isomeric states is discussed.

关键词： rotational band isomeric state hexadecapole-hexadecapole interaction projected shell model