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Angular Momentum-Phase Coherent State for an Electron in Uniform Magnetic Field

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Chinese Physics Letters 2001年第3期18卷 319-321页

作者： fan Hong-Yi fan Yue Department of Material Science and Engineering University of Science and Technology of ChinaHefei 230026

Based on the newly constructed state|l,r>>[fan et al.,***.16(1999)706],where l is the angular mometum quantum number and r denotes the electron's orbit radius in a uniform magnetic field,we propose a new angular momentum-phase coherent state by introducing a new operator A.A and A^(†)are annihilation and creation operator in the|l,r>>space,*** coherent state is A's eigenket and possesses non-orthonormal and overcomplete properties,it is constructed on the certain superposition of zero-angular momentum states along the radius direction.

关键词： radius angular momentum

基于电力系统高压生产设备电气故障自动化监测技术

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科学技术创新 2025年第2期 19-22页

作者：范建军国能新朔铁路有限责任公司供电分公司内蒙古鄂尔多斯

本文提出了一种基于电力系统高压设备的电气故障自动化监测技术,通过运维结构模型和链路均衡控制模型优化故障信息分析,利用三维数据重组和高阶统计量方法提取故障特征,并通过三维相空间重构实现故障数据的可视化和自动化诊断。仿真实... 详细信息

本文提出了一种基于电力系统高压设备的电气故障自动化监测技术,通过运维结构模型和链路均衡控制模型优化故障信息分析,利用三维数据重组和高阶统计量方法提取故障特征,并通过三维相空间重构实现故障数据的可视化和自动化诊断。仿真实验结果显示,该技术能准确快速检测和定位故障,显著提升电力系统的自动化监测能力。

关键词：电力系统高压生产设备自动化监测故障诊断三维数据重组

Influence of Wall Effect on Comprehensive Controllability for Ducted fan Aircraft

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journal of Beijing Institute of Technology 2020年第4期29卷 581-591页

作者： Tianfu Ai Changle Xiang Bin Xu Wei fan Yibo Zhang Vehicle research Center School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high *** state space equation of the system can be obtained by correlation deduction and identification of the whole prototype *** on the duct test bench experiment and computational fluid dynamics(CFD)simulation analysis,the expressions between the different distances dWE from the rotor center of the prototype to the wall and the thrust,reaction torque,and tilting moment of the system under hovering conditions are *** influence of the wall effect of the prototype is incorporated into the system model to analyze the relationship between distance dWE and the comprehensive controllability of the *** results show that the system comprehensive controllability vector of other channels changes little with the decrease of the distance dWE,and only the controllability vector of the rolling channel increases *** the same time,the tilting moment also increases significantly,which strengthens the tendency of the prototype to tilt towards the wall.

关键词： coaxial ducted fan aircraft hovering condition wall effect tilting moment comprehensive controllability analysis

A Multilevel Splitting Algorithm for Quick Sampling

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Tsinghua Science and Technology 2021年第4期26卷 417-425页

作者： Liping Wang Wenhui fan Department of Automation Tsinghua UniversityBeijing 100084China

To reduce intermediate levels of splitting process and enhance sampling accuracy, a multilevel splitting algorithm for quick sampling is proposed in this paper. Firstly, the selected area of the elite set is expanded to maintain the diversity of the samples. Secondly, the combined use of an adaptive difference evolution algorithm and a local searching algorithm is proposed for the splitting procedure. Finally, a suite of benchmark functions are used for performance testing. The results indicate that the convergence rate and stability of this algorithm are superior to those of the classical importance splitting algorithm and an adaptive multilevel splitting algorithm.

关键词： rare event simulation splitting method elite set adaptive differential evolution local searching

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自然语言处理研究综述

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 89-111,F0002页

作者：赵铁军许木璠陈安东哈尔滨工业大学计算学部黑龙江哈尔滨150001

近年来,自然语言处理因在分析与建模人类语言任务领域取得诸多成果而备受关注。当前,大规模预训练语言模型展现出强大的对话问答和文本生成能力,带来自然语言处理研究的新一轮热潮。自然语言处理在机器翻译、文本摘要、信息抽取等领域... 详细信息

近年来,自然语言处理因在分析与建模人类语言任务领域取得诸多成果而备受关注。当前,大规模预训练语言模型展现出强大的对话问答和文本生成能力,带来自然语言处理研究的新一轮热潮。自然语言处理在机器翻译、文本摘要、信息抽取等领域应用广泛。文本首先讨论自然语言处理针对语言学四个不同层次文本信息的分析手段,对自然语言处理的基本任务组成进行概述;其次,讨论自然语言处理在具体下游任务中的应用现状,包括自然语言处理在具体任务中的应用历史、当前的研究趋势以及面临的挑战;最后,在大规模预训练语言模型研究对数据集提出更高要求的背景下,对自然语言处理领域已有的数据集及评测基准集等进行讨论。

关键词：自然语言处理句法分析语义分析机器翻译问答系统信息抽取

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Optimal resource allocation for transmission diversity in multi-radio access networks:a coevolutionary genetic algorithm approach

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Science China(Information Sciences) 2014年第2期57卷 99-112页

作者： fan WenHao LIU YuanAn WU fan Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and Telecommunications Wireless Communications and EMC Laboratory School of Electronic EngineeringBeijing University of Posts and Telecommunications

The next generation wireless communication systems aim at supporting enhanced diversified network access and data transmission abilities via the cooperative integration and unified management of various radio access technologies(rATs).The resource allocation is the core component leading the network system and mobile terminals to the service robustness and performance *** this paper,a numeric optimization model for optimizing terminals’transmission power and allocated rAT bandwidth for maximizing system capacity is proposed with the focal consideration of the multi-radio transmission diversity for parallel transmission through multiple links from diferent rATs,and diferent terminal characteristics on rAT ***,we design a centralized and periodic scheduling algorithm including an improved coevolutionary genetic algorithm for efciently solving the optimization *** results demonstrate that our propose algorithm can distinctly enhance the system performance and improve the computational efciency.

关键词： multi-radio access radio resource management multi-radio transmission diversity Lagrangian method coevolutionary algorithm genetic algorithm

Intricate evolutions of multiple-period post-buckling patterns in bilayers

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Science China(Physics,Mechanics & Astronomy) 2021年第1期64卷 72-81页

作者： Zhe Cheng fan Xu Institute of Mechanics and Computational Engineering Department of Aeronautics and AstronauticsFudan UniversityShanghai200433China

Surface instability of compliant film/substrate bilayers has raised considerable interests due to its broad applications such as wrinkle-driven surface renewal and antifouling,shape-morphing for camouflaging skins,and micro/nano-scale surface patterning ***,it is still a challenge to precisely predict and continuously trace secondary bifurcation transitions in the nonlinear post-buckling ***,we develop lattice models to precisely capture the nonlinear morphology evolution with multiple mode transitions that occur in the film/substrate *** on our models,we reveal an intricate post-buckling phenomenon involving successive flat-wrinkle-doubling-quadrupling-fold ***-stretch and pre-compression of the substrate,as well as bilayer modulus ratio,can alter surface morphology of film/substrate *** high substrate pre-tension,hierarchical wrinkles emerge in the bilayer with a low modulus ratio,while a wrinkle-to-ridge transition occurs with a high modulus ***,with moderate substrate pre-compression,the bilayer eventually evolves into a period-tripling *** diagrams based on neo-Hookean and Arruda-Boyce constitutions are drawn to characterize the influences of different factors and to provide an overall view of ultimate pattern *** understanding and quantitative prediction of the nonlinear morphological transitions of soft bilayer materials hold potential for multifunctional surface regulation.

关键词： hierarchical wrinkle period-doubling period-tripling period-quadrupling fold ridge

Optimal Location Allocation Strategy of Gas-fired Unit in Transmission Network

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journal of Modern Power Systems and Clean Energy 2020年第2期8卷 229-237页

作者： jiale fan Xiaoyang Tong the School of Electrical Engineering Southwest Jiaotong UniversityChengduChina

The gas-fired generation has recently become an important power source for power *** increasing integration of gas-fired units(GFUs)brings a problem of location allocation strategy for power system *** paper proposes a bi-level maximum-minimum optimal placement model of GFUs to improve the static voltage stability in the transmission *** the first stage,the locations of installed GFUs are optimized to improve the static voltage stability *** optimal installed capacity of GFUs is determined to minimize the operation costs and power losses in the second *** proposed mixed-integer nonlinear programming(MINLP)model is solved by second-order cone programming *** results in the IEEE 118-bus test system demonstrate the effectiveness of the proposed method and the static voltage stability can be improved.

关键词： Integrated energy systems gas-fired unit(GFU) static voltage stability optimal power flow

西北绿洲灌区玉米叶片衰老特征对不同地膜覆盖利用方式的响应

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作物学报 2025年第1期51卷 233-246页

作者：王丽萍李盼赵连豪樊志龙胡发龙范虹何蔚柴强殷文甘肃农业大学农学院/省部共建干旱生境作物学国家重点实验室甘肃兰州730070

西北绿洲灌区玉米传统生产模式中大量使用地膜伴随着生态环境污染严重,且在极端高温下玉米出现叶片早衰。针对该现象,通过免耕一膜2年覆盖利用技术探讨延缓玉米叶片衰老并增加玉米产量的可行性,以期为构建西北绿洲灌区地膜减量玉米高效... 详细信息

西北绿洲灌区玉米传统生产模式中大量使用地膜伴随着生态环境污染严重,且在极端高温下玉米出现叶片早衰。针对该现象,通过免耕一膜2年覆盖利用技术探讨延缓玉米叶片衰老并增加玉米产量的可行性,以期为构建西北绿洲灌区地膜减量玉米高效生产技术提供理论支撑。2013年在西北绿洲灌区设置免耕一膜2年覆盖利用(NTP)、秋免耕春覆膜(rTP)和传统每年覆新膜(对照, CTP) 3种处理(本文采用2021-2023数据),探究玉米叶片光合源、持绿特性、细胞抗氧化酶活性和渗透调节物质含量对不同地膜覆盖利用方式的响应。结果表明,NTP和rTP可有效调节玉米生育期内光合源和叶片持绿性能的动态关系,维持生育后期较大的叶面积指数(LAI)、光合势(LAD)、叶片持绿性(SG)和叶绿素相对含量(SPAD),有利于延缓叶片衰老。与CTP相比, NTP玉米出苗后75~120 d的LAI、LAD、SG和SPAD分别提高15.1%~16.1%、14.8%~15.5%、7.2%~9.2%和11.3%~11.7%,rTP分别提高12.4%~13.0%、11.5%~12.4%、10.0%~17.6%和6.0%~6.7%。同时,通过单株绿色叶面积的拟合,发现NTP和rTP较CTP叶片衰老时间平均推迟了5.8~7.0d和6.2~7.7d,这可能是由于NTP和rTP有助于增强玉米大喇叭口期-灌浆期叶片的抗氧化能力和细胞渗透调节作用。玉米出苗后60~105 d, NTP较CTP叶片抗氧化酶(SOD、POD、CAT和APX)活性分别提高17.6%~20.0%、28.4%~34.4%、6.7%~8.4%和8.3%~10.9%, rTP较CTP分别提高11.3%~11.7%、16.9%~18.2%、4.4%~6.1%和5.8%~7.7%。此外,与CTP相比,NTP与rTP可溶性蛋白和脯氨酸含量分别提高35.9%~43.9%和29.5%~31.8%,20.7%~31.7%和17.4%~20.4%,丙二醛含量分别降低26.0%~27.8%和17.5%~25.9%。NTP对抗氧化酶和渗透调节物质的影响更大,NTP较CTP增产5.2%~6.0%。免耕一膜2年覆盖利用技术是西北灌区在实现资源减投条件下,有效延缓玉米叶片衰老且增加产量的适宜措施。

关键词：地膜覆盖光合源抗氧化酶活性细胞渗透调节能力籽粒产量

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