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光谱学与光谱分析 1998年第4期18卷 411-415页

作者：满宝元王公堂刘爱华王象泰山东师范大学物理系

用时间和空间分辨诊断技术研究了脉冲激光烧蚀不同气压环境下金属Ａｌ靶过程中产生的等离子体羽的特性。

关键词：激光烧蚀时间分辨光谱等离子体铝靶气压

基于Relief和BFO的并行支持向量机算法

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计算机应用研究 2022年第2期39卷 447-455页

作者：胡健王祥太毛伊敏刘蔚江西理工大学信息工程学院江西赣州341000 赣南科技学院电子信息工程学院江西赣州341000

针对大数据环境下并行支持向量机(SVM)算法存在冗余数据敏感、参数选取困难、并行化效率低等问题,提出了一种基于Relief和BFO算法的并行SVM算法RBFO-PSVM。首先,基于互信息和Relief算法设计了一种特征权值计算策略MI-Relief,剔除数据集... 详细信息

针对大数据环境下并行支持向量机(SVM)算法存在冗余数据敏感、参数选取困难、并行化效率低等问题,提出了一种基于Relief和BFO算法的并行SVM算法RBFO-PSVM。首先,基于互信息和Relief算法设计了一种特征权值计算策略MI-Relief,剔除数据集中的冗余特征,有效地降低了冗余数据对并行SVM分类的干扰;接着,提出了基于MapReduce的MR-HBFO算法,并行选取SVM的最优参数,提高SVM的参数寻优能力;最后,提出核聚类策略KCS,减小参与并行化训练的数据集规模,并提出改进CSVM反馈机制的交叉融合级联式并行支持向量机CFCPSVM,结合MapReduce编程框架并行训练SVM,提高了并行SVM的并行化效率。实验表明,RBFO-PSVM算法对大型数据集的分类效果更佳,更适用于大数据环境。

关键词： SVM算法 MapReduce CFCPSVM模型 MI-Relief策略 MR-HBFO算法

旅游流网络结构韧性特征变化及其影响因素——以贵州省为例

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经济地理 2024年第3期44卷 229-240页

作者：王坤陈祥泰黄震方贵州大学旅游与文化产业学院贵州贵阳550025 南京师范大学地理科学学院江苏南京210023

文章通过网络爬虫获取贵州省2010—2022年旅游流数据,构建旅游流网络及其结构韧性的综合评估及攻击指标体系,并借助复杂网络、指数随机图等方法,实证探讨了贵州省旅游流网络结构韧性的变化特征及其影响因素。结果表明:(1)贵州省旅游流... 详细信息

文章通过网络爬虫获取贵州省2010—2022年旅游流数据,构建旅游流网络及其结构韧性的综合评估及攻击指标体系,并借助复杂网络、指数随机图等方法,实证探讨了贵州省旅游流网络结构韧性的变化特征及其影响因素。结果表明:(1)贵州省旅游流网络结构韧性呈现先下降后上升的态势,旅游流网络联系的增强并未带来网络结构韧性的提升。韧性水平较高的地区多为东南部的旅游中心城市;(2)分维度来看,贵州省旅游流网络形成了较为典型的“核心—边缘”层级结构,网络的匹配性明显,传输性在不断提升,小团体集聚现象开始凸显;(3)旅游流网络结构在随机攻击下呈现出鲁棒性特征,而在蓄意攻击下脆弱性较为显著,且在蓄意攻击下网络承受能力随时间推移整体呈现上升趋势,旅游流核心网络不断拓展;(4)网络内生结构、个体属性以及外生网络变量共同影响着旅游流网络结构韧性变化。其中,网络互惠性、经济水平、产业结构、政府支持与接待能力对旅游流网络结构韧性变化具有显著正向影响,市场规模对旅游流网络结构韧性变化的正向作用不断凸显,而网络边数与空间距离对旅游流网络结构韧性变化具有明显的抑制作用。

关键词：旅游流网络结构韧性攻击模拟游记文本市场规模产业结构风险防范

质子交换MgO：Linbo_3波导及其镁含量对波导性能影响的研究

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中国激光 1995年第5期22卷 347-352页

作者：卓壮王象泰孟宪林王继扬邵宗书徐观峰山东师范大学物理系山东大学晶体材料研究所西南技术物理所

报道了不同镁含量质子交换ＭｇＯ：ＬｉＮｂＯ３波导的制备与表征。采用多个测量波长，测量并计算了不同镁含量的Ｚ切质子交换ＭｇＯ：ＬｉＮｂＯ３波导的阶跃式折射率分布，结果表明多波长测量结果一致。给出了波导层折射率增量的波长... 详细信息

报道了不同镁含量质子交换ＭｇＯ：ＬｉＮｂＯ３波导的制备与表征。采用多个测量波长，测量并计算了不同镁含量的Ｚ切质子交换ＭｇＯ：ＬｉＮｂＯ３波导的阶跃式折射率分布，结果表明多波长测量结果一致。给出了波导层折射率增量的波长色散，发现了波导层折射率增量和同一温度下波导的扩散系数随晶体中镁含量的增加而减小，最后讨论了镁含量对波导性能影响的机制。

关键词：质子交换波导镁性能

Swarm intention identification via dynamic distribution probability image

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Chinese Journal of Aeronautics 2024年第10期37卷 380-392页

作者： Yinhan wang Jiang wang Shaoming HE Fei wang Qi wang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

In the realm of decision-making for defense and security applications,it is paramount to swiftly and accurately identify the intentions of incoming *** identification methods predominantly focus on single-target applications and overlook the perturbations introduced by measurement *** this study,we propose a novel concept:the Dynamic Distribution Probability(DDP)image,which is constructed using the estimated state and its covariance *** grayscale pixel value within the image signifies the probability of the presence of the agent within the *** proposed identification scheme integrates the use of Extended Kalman Filter(EKF),Convolutional Neural Network(CNN),Back Propagation(BP)network,and Gated Recurrent Unit(GRU)***,the DDP image is processed through a CNN to distill the formation characteristics,and the estimated swarm state from EKF is inputted into a BP network to deduce the kinematic *** outputs from both networks are summed and subsequently channeled into a GRU network to capture temporal *** numerical simulations and flight experiments are presented to demonstrate the robust anti-noise capability of the proposed scheme compared with conventional methods,as well as its superior training efficiency.

关键词： Intention Identification Kalman filters Convolutional neural networks Swarm intelligence

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

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激光辐照HgCdTe所产生的等离子体特性

中国激光 1998年第6期25卷 528-532页

作者：满宝元王象泰官文栎山东师范大学物理系山东教育学院

脉冲激光束辐照处于不同背景气压的ＨｇＣｄＴｅ表面，用时间和空间分辨诊断技术探测了等离子体的发射谱，根据连续辐射的形状用普朗克公式估测了等离子体的温度，并根据获得的飞行时间谱，测量了等离子体的出射速度，结合实验结果，对... 详细信息

脉冲激光束辐照处于不同背景气压的ＨｇＣｄＴｅ表面，用时间和空间分辨诊断技术探测了等离子体的发射谱，根据连续辐射的形状用普朗克公式估测了等离子体的温度，并根据获得的飞行时间谱，测量了等离子体的出射速度，结合实验结果，对等离子体的特性进行了讨论。

关键词：等离子体飞行时间谱喷射速度激光

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： wang Yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM

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Defence Technology（防务技术） 2024年第3期33卷 463-474页

作者： Yili wang Changsheng Li Xiaofeng wang Nanjing University of Science and Technology Nanjing 210094JiangsuChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of *** address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent *** leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration *** analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,*** model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target *** maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed ***,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves.

关键词： Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion