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Dynamics of momentum distribution and structure factor in a weakly interacting Bose gas with a periodical modulation

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Communications in Theoretical Physics 2020年第12期72卷 171-175页

作者： ning Liu z C Tu Department of Physics Beijing Normal UniversityBeijing 100875China

The momentum distribution and dynamical structure factor in a weakly interacting Bose gas with a time-dependent periodic modulation in terms of the Bogoliubov treatment are *** evolution equation related to the Bogoliubov weights happens to be a solvable Mathieu equation when the coupling strength is periodically *** exact relation between the time derivatives of momentum distribution and dynamical structure factor is derived,which indicates that the single-particle property is strongly related to the two-body property in the evolutions of Bose–Einstein *** is found that the momentum distribution and dynamical structure factor cannot display periodical *** stable dynamics,some particular peaks in the curves of momentum distribution and dynamical structure factor appear synchronously,which is consistent with the derivative relation.

关键词： Bose gas periodical coupling constant dynamical structure factor Mathieu equation

Metallic subwavelength-cavity semiconductor nanolasers

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Light(Science & Applications) 2012年第1期1卷 79-86页

作者： K.Ding C.z.ning School of Electrical Computerand Energy EngineeringArizona State UniversityTempeAZ 85287USA

Miniaturization has been an everlasting theme in the development of semiconductor *** important breakthrough in this process in recent years is the use of metal-dielectric composite structures that made truly subwavelength lasers *** different designs of metallic cavity semiconductor nanolasers have been proposed and *** this article,we will review some of the most exciting progresses in this newly emerging *** particular,we will focus on metallic-cavity nanolasers with volume smaller than wavelength cubed under electrical injection with emphasis on high-temperature *** devices will serve as an important component in the future integrated nanophotonic systems due to its ultra-small size.

关键词： Semiconductor Lasers Nanolasers Plasmons Plasmon Polaritons Metal Cavity

Coarsening Behavior of Gamma Prime Precipitates in a Nickel Based Single Crystal Superalloy

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Journal of Materials Science & Technology 2016年第2期32卷 172-176页

作者： S.Tang L.K.ning T.z.Xin z.zheng University of Chinese Academy of Sciences.Beijing 100049.China Superalloy Division.Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The γ/γ＇ microstructural evolution in a nickel based single crystal superalloy during load-free thermal exposure at 900 ℃ has been further investigated in this paper. The growth characteristics of γ＇ precipitates were discussed in detail. The generation of interfacial dislocations would accelerate the rate of coalescence in the dendrite arms. The average sizes of precipitates were used to compare interface with diffusion controlled growth mechanism and no mechanism seems obviously dominant, although the square rate law gives slightly better fit. The coarsening behavior may be controlled by diffusion through the ragged interface between the γ＇ precipitate and the y matrix.

关键词： Single crystal superalloy Coarsening Interfacial dislocations Rate controlling mechanism

Certificateless network coding proxy signatures from lattice

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Frontiers of Computer Science 2023年第5期17卷 145-152页

作者： Huifang YU ning WANG School of Cyberspace Security Xi’an University of Posts&TelecommunicationsXi’an 710121China

Network coding can improve the information transmission efficiency and reduces the network resource consumption,so it is a very good platform for information *** proxy signatures are widely applied in information security ***,certificateless proxy signatures based on classical number theory are not suitable for the network coding environment and cannot resist the quantum computing *** view of this,we construct certificateless network coding proxy signatures from lattice(LCL-NCPS).LCL-NCPS is new multi-source signature scheme which has the characteristics of anti-quantum,antipollution and *** LCL-NCPS,each source node user can output a message vector to intermediate node and sink node,and the message vectors from different source nodes will be linearly combined to achieve the aim of improving the network transmission rate and network *** terms of efficiency analysis of space dimension,LCL-NCPS can obtain the lower computation complexity by reducing the dimension of proxy *** terms of efficiency analysis of time dimension,LCL-NCPS has higher computation efficiency in signature and verification.

关键词： lattice multi-source signature scheme proxy signature post-quantum

FAILURES AND THE LIFE OF FURNACE TUBES

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 419-425页

作者： F.z.Shen Y.Ding D.M.Hou z.P.ning Y.Lü T.B.Dong A.R.Tuohuti Nanjing University of Technology Nanjing 210009 ChinaNanjing University of Technology Nanjing 210009 ChinaLutianhua Group Incorporated Luzhou 646300 ChinaLutianhua Group Incorporated Luzhou 646300 ChinaLutianhua Group Incorporated Luzhou 646300 ChinaSouthwestern Tarim Exploration & Development Company Zepu 844804 ChinaSouthwestern Tarim Exploration & Development Company Zepu 844804 China

It is showed after the furnace tubes serviced for 8-10 years that the density of damage in the HAz (heat affected zone) of the weld has higher than in parent metals, though the depth of damage is not equal to. By the test of creep crack growth, it is also acquired that under same mechanic parameter C* (t), the rate of creep crack growth in the HAz is more than twice as fast as in parent metals. Two mechanisms (overheating and thermal shock) of failure occurred in an accident are presented. The stress of thermal shock is analyzed, in which the change of the elasticity modulus with the radius ET = /(r) is considered. Based on it, the safety region of the thermal shock is obtained. Finally, two sets of curves for the safe life are suggested which can facilitate to estimate the remaining life of HK-40 or HP-Nb tubes by their creep rupture data.

关键词： failure thermal stock creep crack growth remaining life furnace tube

Beyond Performance of Learning Control Subject to Uncertainties and Noise: A Frequency-Domain Approach Applied to Wafer Stages

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 198-214页

作者： Fazhi Song ning Cui Shuaiqi Chen Kai zhang Yang Liu Xinkai Chen Jiubin Tan IEEE the Center of Ultra-precision Optoelectronic Instrument Engineering Harbin Institute of Technology the Key Laboratory of Ultra-Precision Intelligent Instrumentation Ministry of Industry and Information Technology the State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of Technology the Center of Ultraprecision Optoelectronic Instrument Engineering Harbin Institute of Technology the Key Laboratory of UltraPrecision Intelligent Instrumentation Ministry of Industry and Information Technology the Department of Electronic and Information Systems Shibaura Institute of Technology

The increasingly stringent performance requirement in integrated circuit manufacturing, characterized by smaller feature sizes and higher productivity, necessitates the wafer stage executing a extreme motion with the accuracy in terms of nanometers. This demanding requirement witnesses a widespread application of iterative learning control(ILC), given the repetitive nature of wafer scanning. ILC enables substantial performance improvement by using past measurement data in combination with the system model knowledge. However, challenges arise in cases where the data is contaminated by the stochastic noise, or when the system model exhibits significant uncertainties, constraining the achievable performance. In response to this issue, an extended state observer(ESO) based adaptive ILC approach is proposed in the frequency *** being model-based, it utilizes only a rough system model and then compensates for the resulting model uncertainties using an ESO, thereby achieving high robustness against uncertainties with minimal modeling effort. Additionally, an adaptive learning law is developed to mitigate the limited performance in the presence of stochastic noise, yielding high convergence accuracy yet without compromising convergence speed. Simulation and experimental comparisons with existing model-based and data-driven inversion-based ILC validate the effectiveness as well as the superiority of the proposed method.

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Influence of baffle position on liquid sloshing during braking and turning of a tank truck

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Journal of zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 317-324页

作者： ning KANG Kui LIU School of Transportation Science and Engineering University of A eronautics and Asttvnautics Beijing 100191 China

The influence of baffle position on liquid sloshing during the braking and turning of a tank truck was studied using a volume of fluid (VOF) model. The forces,their positions and weight distribution during braking and the forces and rolling moment during turning were calculated. The reliability of the calculation method was validated by comparisons with experimental results. The results showed that during braking,liquid splashes in the tank and the maximum forces and G (the ratio of weight acting on the front axle to the rear axle) are large when A (the ratio of the arch area above the baffle to the area of cross section)≤0.1. When A≥0.2,as the position of the baffle is lowered,the maximum of Fx (the force in direction x) first decreases then increases,and the maximum of Fy (the force in direction y) and G increase. During turning,liquid splashes in the tank and the maximum forces and M (the rolling moment) are large when D (the ratio of the arch area above the baffle to the area of cross section)≤0.2. When D≥0.3,as the position of the baffle is lowered,the maximums of Fy,Fz (the force in direction z) and M increase.

关键词： Tank truck Volume of fluid (VOF) method Liquid sloshing Two phase flow Baffle

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驱控一体的旋拧式果实采摘执行器设计与试验

农机化研究 2025年第3期47卷 48-55页

作者：严童杰冯青春郭鑫杨宁江苏大学电气信息工程学院江苏镇江212000 北京市农林科学院智能装备技术研究中心北京100097 国家农业智能装备工程技术研究中心北京100097 农业智能装备技术北京市重点实验室北京100097

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并... 详细信息

针对果园智能化采收作业需要,设计了支持总线扩展的驱控一体旋拧采摘末端执行器,旨在为多臂并行采摘机器人研发提供支撑。在对标准苹果树果实物理形态统计分析基础上,结合人工采摘方法,提出了“吸附-夹持-旋拧”的采摘机械操作方法,并设计了基于双舵机驱动的紧凑型采摘执行机构,对其吸盘、夹持和旋拧电机的关键参数进行了优化设计。面向多执行并行采摘需要,设计了基于CANopen通讯的采摘操作驱动器,实现了多执行器的总线扩展。通过现场试验对执行器作业性能进行了测试,结果表明:果实大小在60~100 mm之间,采摘成功率可达到90%,吸盘最优停留时间为1.00 s,吸盘最优接近距离为1.0 mm,最优旋拧角度为360°。

关键词：采摘机器人驱控一体旋拧采摘 CANopen

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Effect of friction on corrosion behaviors of AISI 304 and Cr26Mo1 stainless steels in different solutions

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Journal of Iron and Steel Research International 2023年第12期30卷 2541-2556页

作者： z.X.Dai S.L.Jiang L.K.ning X.D.Xu S.Li D.L.Duan Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026AnhuiChina Liaoning Key Laboratory of Aero-engine Materials Tribology Institute of Metal ResearchChinese Academy of SciencesShenyang110016LiaoningChina AnSteel LISCO Stainless Steel Co. Ltd.Guangzhou510760GuangdongChina

The corrosion and tribocorrosion behaviors of AISI 304 austenitic stainless steel and Cr26Mo1 ultrapure high chromium ferrite stainless steel in 3.5 wt.%NaCl and 0.5 mol/L H2SO4 solutions were *** electrochemical measurement technology was applied to identify electrochemistry behaviors during tribocorrosion tests in *** surface morphologies and compositions of the wear tracks were analyzed by scanning electron microscopy and Raman *** results showed that compositions of stainless steels,corrosive mediums and applied loads have great influence on tribocorrosion behaviors of stainless ***,the corrosion resistance in static state of stainless steels primarily dominates its tribocorrosion behavior;meanwhile,better mechanical properties are in favor of tribocorrosion ***,the corrosion rate is promoted significantly in 3.5%NaCl solution by friction,while the tendency is inconspicuous in 0.5 mol/L H2SO4 *** but not least,passive films on stainless steels can be wiped off by small friction *** the increase in applied load,the effect of friction converts to forming friction oxide film from removing passivation film,so that a critical load exists below which the friction force can promote the corrosion process extremely.

关键词： Tribocorrosion Stainless steel/PEEK friction pair Corrosive medium Applied load Microelectrode probe