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Tropical cyclone genesis over the western north Pacific in La Ni?a decay summers: Comparison between 2.18 and 2.2.

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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 CentreBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China

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 2.18 and2.2. were La Ni?a decay years, but TC activity over the WNP during the two summers(June–August) showed notable differences. In 2.18, 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 2.2., 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 2.17/2.18and persisted until summer 2.18. 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 2.18 increased by approximately 150% relative to climatological state,providing dynamic conditions favorable for TC formation. In 2.2., 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 Nina events Indian Ocean Basin Mode Pacific Meridional Mode Madden-Julian Oscillation Western Pacific Subtropical High Monsoon trough

Exploring a Promising Region and Enhancing Decision Space Diversity for Multimodal Multi-Objective Optimization

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Tsinghua Science and Technology 2024年第2期29卷 325-342页

作者： Fei Ming Wenyin gong School of Computer Science China University of GeosciencesWuhan 430074China

During the past decade,research efforts have been gradually directed to the widely existing yet less noticed multimodal multi-objective optimization problems(MMOPs)in the multi-objective optimization ***,researchers have begun to investigate enhancing the decision space diversity and preserving valuable dominated solutions to overcome the shortage caused by a preference for objective space ***,many existing methods still have limitations,such as giving unduly high priorities to convergence and insufficient ability to enhance decision space *** overcome these shortcomings,this article aims to explore a promising region(PR)and enhance the decision space diversity for handling *** traditional methods,we propose the use of non-dominated solutions to determine a limited region in the PR in the decision space,where the Pareto sets(PSs)are included,and explore this region to assist in solving ***,we develop a novel neighbor distance measure that is more suitable for the complex geometry of PSs in the decision space than the crowding *** on the above methods,we propose a novel dual-population-based coevolutionary *** studies on three benchmark test suites demonstrates that our proposed methods can achieve promising performance and versatility on different *** effectiveness of the proposed neighbor distance has also been justified through comparisons with crowding distance methods.

关键词： multimodal multi-objective optimization evolutionary algorithms promising region neighbor distance decision space coevolution

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

腺苷A_(2.)受体抑制剂伊曲茶碱的合成工艺改进

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中国药物化学杂志 2018年第3期28卷 220-224页

作者：李娟韩雨霏李颖修陈少威宫平沈阳红旗制药有限公司辽宁沈阳110179 沈阳药科大学基于靶点的药物设计与研究教育部重点实验室辽宁沈阳110016

目的对腺苷A_(2.)受体抑制剂伊曲茶碱的合成工艺进行优化。方法以N,N'-二乙基脲和氰基乙酸为起始原料,依次经环合、亚硝化、还原反应制得中间体5,6-二氨基-1,3-二乙基-2.4-(1H,3H)-嘧啶二酮(2.盐酸盐;由3,4-二甲氧基肉桂酸与氯化亚砜反... 详细信息

目的对腺苷A_(2.)受体抑制剂伊曲茶碱的合成工艺进行优化。方法以N,N'-二乙基脲和氰基乙酸为起始原料,依次经环合、亚硝化、还原反应制得中间体5,6-二氨基-1,3-二乙基-2.4-(1H,3H)-嘧啶二酮(2.盐酸盐;由3,4-二甲氧基肉桂酸与氯化亚砜反应制得中间体3,4-二甲氧基肉桂酰氯(14)。中间体2.中间体14经缩合反应得到中间体(E)-N-(6-氨基-1,3-二乙基-2.4-二氧代-1,2.3,4-四氢嘧啶-5-基)-3-(3,4-二甲氧基苯基)丙烯酰胺(7),7经过环合、甲基化得到目标产物伊曲茶碱。结果与结论目标化合物的结构经~1H-NM R、^(13)C-NM R和M S谱确证,总收率为32.8%(以N,N'-二乙基脲计),纯度达99.91%(HPLC法)。优化后的工艺路线所用原料廉价易得,操作简便,条件温和,收率较高,可为工业化生产提供参考。

关键词：腺苷A2.受体拮抗剂伊曲茶碱工艺改进

Phase-modulated multi-foci microscopy for rapid 3D imaging

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Photonics Research 2024年第7期12卷 1548-1555页

作者： WEIQI WANG LI gong ZHIWEI HUANG Optical Bioimaging Laboratory Department of Biomedical EngineeringCollege of Design and EngineeringNational University of SingaporeSingapore 117576Singapore

3D imaging technology is pivotal in monitoring the functional dynamics and morphological alterations in living cells and ***,conventional volumetric imaging associated with mechanical z-scanning encounters challenges in limited 3D imaging speed with inertial ***,we present a unique phase-modulated multifoci microscopy (PM^(3)) technique to achieve snapshot 3D imaging with the advantages of extended imaging depths and adjustable imaging intervals between each focus in a rapid *** accomplish the tasks,we utilize a spatial light modulator (SLM) to encode the phases of the scattered or fluorescence light emanating from a volumetric sample and then project the multiple-depth images of the sample onto a single charge-coupled device camera for rapid 3D *** demonstrate that the PM^(3)technique provides~55-fold improvement in imaging depth in polystyrene beads phantom compared to the depth of field of the objective lens ***^(3)also enables the real-time monitoring of Brownian motion of fluorescent beads in water at a 15 Hz volume *** precisely manipulating the phase of scattered light on the SLM,PM^(3)can pinpoint the specific depth information in living zebrafish and rapidly observe the 3D dynamic processes of blood flow in the zebrafish *** work shows that the PM^(3)technique developed is robust and versatile for fast 3D dynamic imaging in biological and biomedical systems.

关键词： alterations scattered beads

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

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