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Non-relativistic Limit of Dirac Equations in Gravitational Field and Quantum Effects of Gravity

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Communications in Theoretical Physics 2006年第3期45卷 452-456页

作者： WU ning Institute of High Energy Physics P.O. Box 918-1 Beijing 100049 China

Based on unified theory of electromagnetic interactions and gravitational interactions, the non-relativistic limit of the equation of motion of a charged Dirac particle in gravitational field is studied. From the Schroedinger equation obtained from this non-relativistic limit, we can see that the classical Newtonian gravitational potential appears as a part of the potential in the Schroedinger equation, which can explain the gravitational phase effects found in COW experiments. And because of this Newtonian gravitational potential, a quantum particle in the earth＇s gravitational field may form a gravitationally bound quantized state, which has already been detected in experiments. Three different kinds of phase effects related to gravitational interactions are studied in this paper, and these phase effects should be observable in some astrophysical processes. Besides, there exists direct coupling between gravitomagnetic field and quantum spin, and radiation caused by this coupling can be used to directly determine the gravitomagnetic field on the surface of a star.

关键词： quantum gravity gauge field quantum effects of gravity

Synchronization criteria for multiple memristor-based neural networks with time delay and inertial term

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Science China(Technological Sciences) 2018年第4期61卷 612-622页

作者： LI ning CAO JinDe College of Mathematics and Information Science Henan University of Economics and Law School of Mathematics and Research Center for Complex Systems and Network Sciences Southeast University

This present work uses different methods to synchronize the inertial memristor systems with linear coupling. Firstly, the mathematical model of inertial memristor-based neural networks(IMNNs) with time delay is proposed, where the coupling matrix satisfies the diffusion condition, which can be symmetric or asymmetric. Secondly, by using differential inclusion method and Halanay inequality, some algebraic self-synchronization criteria are obtained. Then, via constructing effective Lyapunov functional, designing discontinuous control algorithms, some new sufficient conditions are gained to achieve synchronization of networks. Finally, two illustrative simulations are provided to show the validity of the obtained results, which cannot be contained by each other.

关键词： memristor-based neural networks(MNNs) inertial term synchronization discontinuous control

Controlled Radical Polymerization:from Oxygen Inhibition and Tolerance to Oxygen Initiation

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Chinese Journal of Polymer Science 2021年第9期39卷 1084-1092页

作者： ning Li Xiang-Cheng Pan State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Molecular oxygen is a radical scavenger in both conventional and controlled radical polymerization(CRP),resulting in many time-consuming methods for physically removing oxygen before the *** approaches have been developed to have oxygen toleranee by chemically consuming or converting molecular oxygen into non-initiating species to address this ***,we propose another approach called oxygen initiation that directly transforms molecular oxygen into the initiating carbon radical in *** feature article summarizes our rece nt developments in this *** n-initiated reversible additi on-fragmentation transfer(RAFT)polymerization has been successfully conducted using oxygen and trialkylborane as co-initiators under the ambient conditions and atmosphere without any prior degassed *** gas-triggered initiation provides the opportunity for spatiotemporal control of the polymerization by molecular oxygen or *** synthesized alkylborane compounds could derive the predesigned structure of the initiating alkyl radical to minimize the side reacti ons and free polymer chai ns,achievi ng the synthesis of ultra-high molecular weight *** challe nges and perspectives are also discussed in the end.

关键词： Oxygen Radical polymerization Controlled Alkylborane RAFT

等级型城市群应急物资储备库网络优化模型——以京津冀城市群为例

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西南大学学报（自然科学版） 2025年第1期47卷 226-238页

作者：陆相林于峰赵宁石家庄学院经济管理学院石家庄050035 临沂大学商学院山东临沂276005

构建具有等级性、多目标特征的应急物资储备库网络,对于城市群应急物资储备库的良性互动和城市群应急物资储备库网络的协同发展具有重要现实意义。结合城市群实际情况,对传统的等级设施选址模型加以改进,以实现城市群内受灾点民众接受... 详细信息

构建具有等级性、多目标特征的应急物资储备库网络,对于城市群应急物资储备库的良性互动和城市群应急物资储备库网络的协同发展具有重要现实意义。结合城市群实际情况,对传统的等级设施选址模型加以改进,以实现城市群内受灾点民众接受应急物资配置总满意度最大、应急物资储备库之间总关联度最高和应急物资储备建设与储存成本最小为目标,构建了适用于城市群应急物资储备库网络优化的等级型设施选址模型。针对所构建模型的等级性、多目标特点,对传统两阶段启发式算法进行拓展,设计了三阶段启发式算法加以求解。以京津冀城市群为例进行实证,优化结果表明:所构建模型稳健性较强,所设计算法能实现对模型的有效求解。京津冀城市群内应设立北京市、天津市、石家庄市等6个区域级应急物资储备库,且进一步形成由区域级、市级、县(市、区)级3个等级构成的应急物资储备库网络协作区。

关键词：应急物资储备库网络等级多目标设施选址三阶段启发式算法京津冀城市群

基于CFD的玉米田间吊喷装置仿真设计与试验

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农机化研究 2025年第1期47卷 106-113,156页

作者：徐宁胡敏英桑永英王锦轩河北农业大学机电工程学院河北保定071000

为了改善玉米作物生长至中后期时中下层叶片雾滴沉积效果差,不同冠层雾滴分布不均导致植株叶片整体雾滴覆盖率低,喷施农药方式不佳造成药害和环境污染的问题,设计了一种玉米田间吊喷装置。利用数学理论几何关系结合Fluent软件确定了关... 详细信息

为了改善玉米作物生长至中后期时中下层叶片雾滴沉积效果差,不同冠层雾滴分布不均导致植株叶片整体雾滴覆盖率低,喷施农药方式不佳造成药害和环境污染的问题,设计了一种玉米田间吊喷装置。利用数学理论几何关系结合Fluent软件确定了关键参数,即吊杆长度为1950 mm、侧下喷头距吊杆底端高度为50 mm、侧上喷头距植株顶端高度为50 mm、侧下喷头与水平方向上夹角为38.8°、侧上喷头与水平方向上夹角为43.7°。利用Design-Expert软件以吊杆侧上喷口处压强、吊杆侧下喷口处压强、机具行进速度为试验因素,以叶片平均雾滴覆盖率Y为试验指标设计三因素三水平正交试验,经方差分析后得到影响雾滴覆盖率大小因素主次顺序:行进速度>侧下压强>侧上压强。经田间试验后得到最终组合参数为机具行进速度0.8 m/s,侧上压强0.7 MPa,侧下压强0.5 MPa,雾滴覆盖率为26.54%,上、中、下层叶片雾滴覆盖率分别为28.32%、23.54%、27.75%,模型仿真与田间试验相对误差为5.05%。研究结果可为玉米植保机械的研发提供参考。

关键词：吊喷装置病虫害 CFD 药害污染雾滴覆盖率玉米

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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

Synchronization of noise-perturbed optical systems with multiple time delays

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Chinese Physics B 2012年第2期21卷 187-192页

作者： Tang Mao-ning School of Science Huzhou UniversityHuzhou 313000China

In this paper, complete synchronization and generalized synchronization between two unidirectionally coupled optical systems with multiple time delays and noise perturbation are investigated. Sufficient conditions for both complete synchronization and generalized synchronization are rigorously established. Numerical simulations fully support the theoretical results. The effect of parameter mismatch on the quality of synchronization is also explored.

关键词： synchronization noise time delayt

A Diagnostic Study of the Influence of Early Spring Soil Moisture in Southeastern China on Interannual Variability of the East Asian Subtropical Summer Monsoon Onset

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Journal of Meteorological Research 2023年第1期37卷 45-57页

作者： Zifan ning Renhe ZHANG Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438 China Meteorological Administration-Fudan University Joint Laboratory of Marine Meteorology Shanghai 200438 Innovation Center of Ocean and Atmosphere System Zhuhai-Fudan Innovation Research InstituteZhuhai 519031 Shanghai Scientific Frontier Base for Ocean-Atmosphere Interaction Studies Fudan UniversityShanghai 200438

The effect of soil moisture(SM)on the onset of East Asian subtropical summer monsoon(EASSM)is investigated based on multiple sets of reanalysis data in the period of 1981–*** is found that the EASSM is characterized by persistent 2-m s^(−1) southerly winds for about 3 months in spring at 850 hPa over the subtropical region of East *** this feature of the meridional winds,we define the EASSM onset date,and obtain that the climatological onset date is pentad 17.7,around 26 *** the interannual timescale,the onset date of EASSM exhibits statistically significant correlation with the SM in southeastern China in the month preceding the onset,with wetter(drier)conditions being associated with later(earlier)*** physical process by which the preceding SM affects the EASSM onset is further explored by examining the surface energy balance as well as its ***(negative)SM anomalies in southeastern China in the month before onset may induce negative(positive)surface temperature *** decreased(increased)surface temperature in southeastern China before the EASSM onset weakens(strengthens)the zonal sea–land thermal contrast in the surface and low-level atmosphere in the subtropical East *** zonal sea–land thermal contrast in wetter(drier)years induces anomalous northerly(southerly)winds over southeastern China,which tends to delay(advance)the zonal thermal seasonal transition in spring and is conducive to a later(earlier)onset of *** results are helpful for understanding and prediction of the variability of EASSM and the EASSM onset.

关键词： soil moisture(SM) East Asian subtropical summer monsoon(EASSM) sea-land thermal contrast onset

Position Optimization for Mobile Relay Communications with Constrained Energy over a Whole Horizontal Plane

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China Communications 2023年第5期20卷 340-350页

作者： Haijun Tan ning Xie Guangdong Key Laboratory of Intelligent Information Processing College of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China

This paper concerns the position optimization problem of a mobile relay over a whole horizontal *** problem is important because the position of a mobile relay directly affects the end-to-end performance,e.g.,reliability,connectivity,and data *** this paper,we propose a new position optimization scheme of a mobile relay over a whole horizontal plane based on the one-bit feedback information from the destination node,which improves the performance over the prior scheme whose position of the mobile relay is optimized over a fixed *** the proposed scheme,the mobile relay is equipped with merely one single onboard ***,no prior information about the positions of both the source node and the destination node is ***,the proposed scheme can work at low network resources scenario,which is particularly suitable for mobile relay communication with constrained energy,e.g.,the communications in a disaster area where the infrastructure is heavily damaged,volcano monitoring,and wireless powered communication *** to the characteristics of the proposed scheme,we further design two heuristic implementations to calculate the optimal position of a mobile relay over a whole horizontal *** first implementation has better steady performance whereas the second implementation has better convergence *** implement the proposed scheme and conduct an extensive performance comparison between the proposed scheme and prior schemes to verify the advantages of the proposed scheme.

关键词： mobile relay position optimization one bit feedback information whole horizontal plane energy constrained