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非定心式等角速传动理论的论证与应用

机械设计与制造 2006年第10期 18-19页

作者：常德功赵欣青岛科技大学青岛266061

针对目前初步形成的非定心式等角速传动理论,通过建立合适的坐标和运动关系示意图,运用矢量分析法验证了这一理论的准确性;并对现有的非定心式等角速理论产品提出了以后发展的方向。在等角速联轴器的理论发展和应用推广方面都具有较大... 详细信息

针对目前初步形成的非定心式等角速传动理论,通过建立合适的坐标和运动关系示意图,运用矢量分析法验证了这一理论的准确性;并对现有的非定心式等角速理论产品提出了以后发展的方向。在等角速联轴器的理论发展和应用推广方面都具有较大的意义。

关键词：非定心式矢量分析法等分角平面万向联轴器

BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： Yu Zhang Bei gong Qian Wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication

考虑动载荷和表面粗糙度的渐开线齿轮摩擦因数的研究

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工程设计学报 2014年第3期21卷 285-291页

作者：邹玉静常德功青岛科技大学机电工程学院山东青岛266061

进行齿面摩擦因数的研究,对于减少摩擦损失、改善系统传动性能等具有重要的意义.建立渐开线圆柱齿轮的非线性时变单自由度动力学模型,求解得到动态啮合力和单对轮齿的受力.结合载荷分担概念和弹流润滑理论,得到考虑表面粗糙度和动态载... 详细信息

进行齿面摩擦因数的研究,对于减少摩擦损失、改善系统传动性能等具有重要的意义.建立渐开线圆柱齿轮的非线性时变单自由度动力学模型,求解得到动态啮合力和单对轮齿的受力.结合载荷分担概念和弹流润滑理论,得到考虑表面粗糙度和动态载荷的不同啮合位置处的齿面摩擦因数,并与静态载荷条件的结果进行对比.同时分析转速、表面粗糙度和润滑剂黏度等工作条件对摩擦因数的影响.研究结果表明:动态载荷对油膜厚度、油膜承载比例和摩擦因数均有一定程度的影响.进入啮合段,油膜较薄,油膜承载比例较低.退出啮合段,油膜增厚,油膜承载比例增高.转速对摩擦因数的影响并非单调的,摩擦因数先是随着转速的增大显著减小,而后随着转速的增大而增大.随着表面粗糙度的增大,摩擦因数随之明显增大.在一定的黏度范围内,随着润滑剂黏度的增大,摩擦因数随之明显减小.

关键词：摩擦因数渐开线圆柱齿轮动态载荷表面粗糙度弹流润滑

Time-of-flight resolved stimulated Raman scattering microscopy using counter-propagating ultraslow Bessel light bullets generation

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Light(Science & Applications) 2024年第7期13卷 1427-1440页

作者： Shulang Lin Li gong Zhiwei Huang Optical Bioimaging Laboratory Department of Biomedical EngineeringCollege of Design and EngineeringNational University of SingaporeSingapore 117576Singapore

We present a novel time-of-flight resolved Bessel light bullet-enabled stimulated Raman scattering(B2-SRS)microscopy for deeper tissue 3D chemical imaging with high resolution without a need for mechanical *** accomplish the tasks,we conceive a unique method to enable optical sectioning by generating the counterpropagating pump and Stokes Bessel light bullets in the sample,in which the group velocities of the Bessel light bullets are made ultraslow(e.g.,vg≈0.1c)and tunable by introducing programmable angular dispersions with a spatial light *** theoretically analyze the working principle of the collinear multicolor Bessel light bullet generations and velocity controls with the relative time-of-flight resolved detection for SRS 3D deep tissue *** have also built the B2-SRS imaging system and present the first demonstration of B2-SRS microscopy with Bessel light bullets for 3D chemical imaging in a variety of samples(e.g.,polymer bead phantoms,biological samples such as spring onion tissue and porcine brain)with high *** B2-SRS technique provides a>2-fold improvement in imaging depth in porcine brain tissue compared to conventional SRS *** method of optical sectioning in tissue using counter-propagating ultraslow Bessel light bullets developed in B2-SRS is generic and easy to perform and can be readily extended to other nonlinear optical imaging modalities to advance 3D microscopic imaging in biological and biomedical systems and beyond.

关键词： Bessel resolved propagating

Even Search in a Promising Region for Constrained Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 474-486页

作者： Fei Ming Wenyin gong Yaochu Jin School of Computer Science China University of GeosciencesWuhan 430074China IEEE Faculty of Technology Bielefeld UniversityNorth Rhine-Westphalia 33619Germany School of Engineering Westlake UniversityHangzhou 310030China

In recent years, a large number of approaches to constrained multi-objective optimization problems(CMOPs) have been proposed, focusing on developing tweaked strategies and techniques for handling constraints. However, an overly finetuned strategy or technique might overfit some problem types,resulting in a lack of versatility. In this article, we propose a generic search strategy that performs an even search in a promising region. The promising region, determined by obtained feasible non-dominated solutions, possesses two general ***, the constrained Pareto front(CPF) is included in the promising region. Second, as the number of feasible solutions increases or the convergence performance(i.e., approximation to the CPF) of these solutions improves, the promising region shrinks. Then we develop a new strategy named even search,which utilizes the non-dominated solutions to accelerate convergence and escape from local optima, and the feasible solutions under a constraint relaxation condition to exploit and detect feasible regions. Finally, a diversity measure is adopted to make sure that the individuals in the population evenly cover the valuable areas in the promising region. Experimental results on 45 instances from four benchmark test suites and 14 real-world CMOPs have demonstrated that searching evenly in the promising region can achieve competitive performance and excellent versatility compared to 11 most state-of-the-art methods tailored for CMOPs.

关键词： Constrained multi-objective optimization even search evolutionary algorithms promising region real-world problems

Tropical cyclone genesis over the western north Pacific in La Ni?a decay summers: Comparison between 2018 and 2021

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Science China Earth Sciences 2024年第10期67卷 3098-3109页

作者： Yunyun LIU Zhensong gong China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate Centre Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology

As the primary interannual signal of variability in the tropical ocean-atmosphere interaction, the El Ni?o-Southern Oscillation has a considerable impact on tropical cyclone(TC) activity over the western North Pacific(WNP). Both 2018 and2021 were La Ni?a decay years, but TC activity over the WNP during the two summers(June–August) showed notable differences. In 2018, summer TC activity was unusually high with a total of 18 TCs, and the region of TC genesis was mainly in the central and eastern WNP. In contrast, only 9 TCs were generated in summer 2021, and the region of TC genesis was primarily in the western WNP. By comparing the characteristics of the large-scale environmental conditions over the regions of TC genesis, the thermal factors of the tropical oceans, and the activity of the Madden-Julian Oscillation(MJO), this study revealed the possible causes for the marked differences in TC genesis over the WNP during the two summers, which both had a similar background of La Ni?a decay. The Indian Ocean Basin Mode(IOBM) transitioned of a cold anomaly in the winter of 2017/2018and persisted until summer 2018. At the same time, the Pacific Meridional Mode(PMM) maintained a positive phase, leading to eastward and northward displacement of the Western Pacific Subtropical High in summer, and eastward extension of the tropical monsoon trough, which presented conditions conducive to TC genesis over the Northwest Pacific. Moreover, the days when the MJO stagnated in phases 5 and 6 in the summer of 2018 increased by approximately 150% relative to climatological state,providing dynamic conditions favorable for TC formation. In 2021, the IOBM quickly turned to a warm anomaly in March and persisted until summer, whereas the PMM became a negative phase in January and remained so until summer. At the same time,the MJO stagnated in phases 2 and 3 for up to 47 days, with the center of convection located over the western Maritime Continent, producing conditions unconducive to TC ge

关键词： Tropical cyclone La Niña events Indian Ocean Basin Mode Pacific Meridional Mode Madden-Julian Oscillation Western Pacific Subtropical High Monsoon trough

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Secure Tracking Control via Fixed-Time Convergent Reinforcement Learning for a UAV CPS

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1699-1701页

作者： Zhenyu gong Feisheng Yang the School of Automation Northwestern Polytechnical UniversityXi’an 710129 the Research&development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China

dear Editor,This letter is concerned with the secure tracking control problem in the unmanned aerial vehicle(UAV) system by fixed-time convergent reinforcement learning(RL). By virtue of the zero-sum game,the false da... 详细信息

关键词： Secure Fixed false

Some Rotundities of Orlicz–Lorentz Spaces

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1893-1919页

作者： Wan Zhong gong Peng WANG department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China

K-UR,K-LUR and K-R are the generalizations of UR,LUR and R respectively,which are of great significance in Banach space *** in Orlicz–Lorentz function spaceΛ_(ϕ,ω)^(◦)[0,γ)equipped with the Orlicz norm,the research methods of K-UR,K-LUR and K-R are much more complicated than those of UR,LUR and *** this paper we obtain some criteria of K-UR,K-LUR and K-R ofΛ_(ϕ,ω)^(◦)[0,γ)by means of the norm of dual space and H_(μ)property ofΛ_(ϕ,ω)^(◦)[0,γ).

关键词： Orlicz-Lorentz space Orlicz norm k-uniform rotundity locally k-uniform rotundity krotundity

Phase modulation of nickel-tin alloys in regulating electrocatalytic nitrogen reduction properties

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Rare Metals 2024年第6期43卷 2851-2858页

作者： Lin Wang Hang-Ning Liu Xin Meng chang-Hui Sun Hai-Dong Liu Liang-Yu gong Zhen-Hua Yan Jie Wang College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural UniversityQingdao 266109China department of Chemistry-Angstrom Laboratory Uppsala University75121UppsalaSweden Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China

Electrocatalytic nitrogen reduction reaction(NRR)is one of the attractive methods for ammonia(NH_(3))production at ambient conditions,but the catalytic performance largely depends on the physical properties of the ***,Ni-Sn alloy nanoparticles with well-controlled physical properties have been synthesized via a simple two-step method,which are applied as efficient electrocatalysts for the NRR.

关键词： alloys alloy nickel