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Equipment damage measurement method of wartime based on FCE-PCA-RF

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Journal of Systems Engineering and Electronics 2024年第3期35卷 707-719页

作者： LI Mingyu GAO Lu xu hongwei LI Kai HUANG Yisong Shijiazhuang Campus of Army Engineering University Shijiazhuang 050003China Shijiazhuang Campus of Army Infantry Academy Shijiazhuang 050227China

As the“engine”of equipment continuous operation and repeated operation, equipment maintenance support plays a more prominent role in the confrontation of symmetrical combat systems. As the basis and guide for the planning and implementation of equipment maintenance tasks, the equipment damage measurement is an important guarantee for the effective implementation of maintenance support. Firstly,this article comprehensively analyses the influence factors to damage measurement from the enemy’s attributes, our attributes and the battlefield environment starting from the basic problem of wartime equipment damage measurement. Secondly, this article determines the key factors based on fuzzy comprehensive evaluation(FCE) and performed principal component analysis (PCA) on the key factors. Finally, the principal components representing more than 85%of the data features are taken as the input and the equipment damage quantity is taken as the output. The data are trained and tested by artificial neural network (ANN) and random forest (RF). In a word, FCE-PCA-RF can be used as a reference for the research of equipment damage estimation in wartime.

关键词： wartime equipment damage fuzzy comprehensive evaluation(FCE) principal component analysis(PCA) artificial neural network(ANN) random forest(RF)

Migration characteristics and profile control capabilities of preformed particle gel in porous media

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Petroleum 2022年第4期8卷 483-498页

作者： Nanjun Lai Shufang Chen Lei Tang Yuaojie Huang hongwei xu School of Chemistry and Chemical Engineering Southwest Petroleum UniversityChengdu610500China

Inspired by the viscoelastic displacement theory,a product called preformed particle gel(PPG)is developed as conformance control agent to enhance oil recovery and control excess water production.The migration law of PPG suspension in porous media is related to its deep profile control and displacement capability.Laboratory experiments indicate that PPG suspension has good viscosity increasing,and the apparent viscosity decreases with the increase of shear rate.PPG suspension is mainly elastic,and its network structure makes it have certain shear stability.PPG particles realize migration in porous media in the way of“accumulation and blockage/pressure increase/deformation and migration”.When the ratio of the PPG particle size to the pore throat diameter d ranges from 35.52 to 53.38,the particles can match through the porous medium.When the permeability difference of the parallel model is 5,PPG suspension has the highest profile improvement rate,69.10%.PPG suspension can adjust the planar heterogeneity,and increase the oil recovery rate by 20.75%.The PPG suspension can effectively start“cluster"、“film”and“blind end residual oil”,and has a high oil washing efficiency.The core NMR T2 spectrum shows that PPG suspension mainly reduces oil saturation in mesopores and macropores.After PPG flooding,the EOR capacity of small pores is the highest,39.11%.

关键词： Preformed particle gel(PPG) Migration law Profile control Flow characteristics Microscopic oil displacement

The Environmental Consequences of Place-Based Policies in China:An Empirical Study Based on SO_(2)Emission Data

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China & World Economy 2022年第4期30卷 201-229页

作者： hongwei xu Wenquan Liang Kuanhu Xiang Institute of Economic and Social Development Dongbei University of Finance and EconomicsChina School of Economics Jinan UniversityChina. School of Economics Shanghai UniversityChina

Previous studies of place-based policies in China have ignored their effect on pollution.Using event study and difference-in-differences methodologies,we investigated the consequences of place-based policies on sulfur dioxide(SO_(2))emissions.We first documented the increase in SO_(2)emissions and SO_(2)emission intensity in the inland region after 2003 at the provincial level.The firm-level data for the period between 1998 and 2010 also showed that the performance of enterprises in noneastern regions in reducing SO_(2)emissions had worsened relatively since 2003,and this effect was particularly strong in enterprises located in central and northeast China,where urban land supply experienced significant growth after 2003.We found that,compared with environmental regulation changes,inland region-biased economic policies after 2003 were more important in explaining the relative changes in SO_(2)emissions between coastal and inland regions.The policy implication is that the central government should address environmental consequences when designing place-based economic policies.

关键词： environmental regulation land supply place-based policies pollution

Invasibility and recoverability of a plant community following invasion depend on its successional stages

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Soil Ecology Letters 2022年第2期4卷 171-185页

作者： hongwei xu Zemin Ai Qing Qu Minggang Wang Guobin Liu Sha xue State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China College of Geomatics Xi'an University of Science and TechnologyXi'anShaanxi 710054China Institute of Soil and Water Conservation Northwest A&F UniversityYangling712100China University of Chinese Academy of Sciences Beijing 100049China Research Center of Forest Management Engineering of State Forestry and Grassland Administration Beijing Forestry UniversityBeijing 100083China

Exotic species invasion represent important causes of harming the structure,function,and ecological environment in ecosystems.Yet,knowledge remains limited on the invasibility(invasion advantage of exotic species)and recoverability(recovery ability of native species)of a plant community following invasion depend on its successional stages.We selected three grasses of Setaria viridis,Artemisia gmelinii,and Bothriochloa ischemum representing early(E),middle(M),and late(L)successional species,respectively.Meanwhile,the grasses of Panicum virgatum was selected to represent exotic species(invasion species).Three types of soil were collected to treat the three E,M,and L successional species,and one type of soil was collected to treat the exotic species.We compared the performance of the three native plant species and one exotic species grown in their“own”and“other”soils in a 2-year greenhouse experiment.Our study showed that exotic species performed better in soils of E and M successional species than in the soil of L successional species.After exotic species removed,E and M successional species exhibited poor growth in the soil of exotic species,while that of L successional species performed poor in field exotic species soils,but performed better in soils disturbed by exotic species.Our study demonstrated that the invasibility and recoverability of native plant communities changed with vegetation succession.

关键词： Invasion advantage Recovery advantage Plant growth Exotic species Grass Greenhouse experiment

On the generalized Chern conjecture for hypersurfaces with constant mean curvature in a sphere

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Science China Mathematics 2021年第7期64卷 1493-1504页

作者： Li Lei hongwei xu Zhiyuan xu Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics Hangzhou Normal UniversityHangzhou 310036China

Let M be a compact hypersurface with constant mean curvature in Denote by H and S the mean curvature and the squared norm of the second fundamental form of M,respectively.We verify that there exists a positive constantγ(n)depending only on n such that if|H|≤γ(n)andβ(n,H)≤S≤β(n,H)+n/18,then S≡β(n,H)and M is a Clifford torus.Here,β(n,H)=n+n^(3)/2(n-1)H^(2)+n(n-2)/2(n-1)(1/2)n^(2)H^(4)+4(n-1)H^(2).

关键词： generalized Chern conjecture hypersurfaces with constant mean curvature rigidity theorem scalar curvature the second fundamental form

A new pinching theorem for complete self-shrinkers and its generalization

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Science China Mathematics 2020年第6期63卷 1139-1152页

作者： Li Lei hongwei xu Zhiyuan xu Center of Mathem atical Sciences Zhejiang UniversityHangzhou 310027China Departm ent of Mathem atics Hangzhou Normal UniversityHangzhou 310036China

In this paper,we firstly verify that if Mn is an n-dimensional complete self-shrinker with polynomial volume growth in Rn+1,and if the squared norm of the second fundamental form of M satisfies 0≤S-1≤1/18,then S≡1 and M is a round sphere or a cylinder.More generally,let M be a complete λ-hypersurface of codimension one with polynomial volume growth in Rn+1 with λ≠0.Then we prove that there exists a positive constant γ,such that if |λ|≤γ and the squared norm of the second fundamental form of M satisfies0≤S-βλ≤1/18,then S≡βλ,λ> 0 and M is a cylinder.Here βλ=1/2(2+λ2+|λ|(λ2+4)1/2).

关键词： rigidity theorem the second fundamental form self-shrinker λ-hypersurface

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基于WOSA-BP的车辆动态称重算法研究

传感技术学报 2024年第1期37卷 50-57页

作者：袁科许素安富雅琼徐红伟中国计量大学机电工程学院浙江杭州310018

测量精度一直是影响车辆动态称重系统有效可靠性的主要因素。针对车辆动态称重系统测量精度较低这个问题,提出了一种基于鲸鱼优化(Whale Optimization Algorithm,WOA)算法和模拟退火(Simulated Annealing,SA)算法混合优化的BP神经网络(B... 详细信息

测量精度一直是影响车辆动态称重系统有效可靠性的主要因素。针对车辆动态称重系统测量精度较低这个问题,提出了一种基于鲸鱼优化(Whale Optimization Algorithm,WOA)算法和模拟退火(Simulated Annealing,SA)算法混合优化的BP神经网络(Back Propagation Neural Network)动态称重模型。首先,简单介绍了动态称重系统的结构和原理。然后,通过小波变换对动态称重系统的采样信号进行过滤重构处理,经过计算得到的动态车重、车速和轴数作为BP神经网络模型的输入参数。其次,建立了一个由WOSA算法优化的BP神经网络来预测实际车辆总重和轴重。最后,比较了WOSA算法优化的BP神经网络模型的预测能力并得出结论。仿真结果表明,WOSA-BP车辆动态称重模型收敛速度快,精度高,最大总重的相对误差为0.58%,最大轴重相对误差为6.73%。

关键词：动态称重 BP神经网络小波变换鲸鱼优化算法模拟退火算法

Transcriptome Profiling of Barley Cultivar Hua 30 MDEC in Response to Agrobacterium Infection

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Phyton-International Journal of Experimental Botany 2022年第6期91卷 1153-1164页

作者： Yingbo Li Ting He Guimei Guo hongwei xu Yingjie Zong Shuwei Zhang Ruiju Lu Longhua Zhou Chenghong Liu Biotech Research Institute Shanghai Academy of Agricultural SciencesShanghai201403China Shanghai Key Laboratory of Agricultural Genetics and Breeding Shanghai201106China

Agrobacterium-mediated transformation has been widely used in plants.However,the mechanism in plant cells’response to Agrobacterium infection was very complex.The mechanism of the determinants in host cell remains obscure,especially in barley,which is recalcitrant for Agrobacterium-mediated transformation.In the present study,microspore-derived embryogenic calli(MDEC)from barley elite cultivar were employed as unique subjects to characterize the mechanisms during the Agrobacterium infection process.Hua 30 MDEC can be successfully infected by Agrobacterium.RNA-sequencing at different infection points(0,2,6,12,24 hpi)was performed.The average expressional intensity of the whole genomics increased from 0 to 2 hpi,and then decreased subsequently.More upregulated than downregulated differentially expressed genes(DEGs)were counted at the same time.GO enrichment analysis showed that protein modification was significantly overrepresented in upregulated DEGs.Chromosome-related biological processes,gene expression and cellular metabolic processes were significantly overrepresented in downregulated DEGs.KEGG analysis showed that plant defense responses,phenylpropanoid biosynthesis and biosynthesis of amino acids were significantly enriched across the infection time course.Nine DEGs related to defense responses were identified.All DEGs were upregulated from 2 to 24 hpi.We speculate that these genes are possibly related to Agrobacterium infection.These findings will provide deep insights into the molecular events occurring during the process of Agrobacterium-mediated transformation.

关键词： Barley Agrobacterium-mediated transformation microspore-derived embryogenic callus transcriptome analysis

Generalized Ejiri’s Rigidity Theorem for Submanifolds in Pinched Manifolds(In memory of Professor Chaohao Gu on his 90th birthday)

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Chinese Annals of Mathematics,Series B 2020年第2期41卷 285-302页

作者： hongwei xu Li LEI Juanru GU Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Applied Mathematics Zhejiang University of TechnologyHangzhou 310023China

Let Mn(n ≥ 4) be an oriented compact submanifold with parallel mean curvature in an(n + p)-dimensional complete simply connected Riemannian manifold Nn+p.Then there exists a constant δ(n, p) ∈(0, 1) such that if the sectional curvature of N satisfies■ , and if M has a lower bound for Ricci curvature and an upper bound for scalar curvature, then N is isometric to Sn+p. Moreover, M is either a totally umbilic sphere■ , a Clifford hypersurface Sm■ in the totally umbilic sphere ■, or■ . This is a generalization of Ejiri’s rigidity theorem.

关键词： Minimal submanifold Ejiri rigidity theorem Ricci curvature Mean curvature