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On the properties of some sets of von Neumann algebras under perturbation

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Science China Mathematics 2015年第8期58卷 1707-1714页

作者： wang liguang School of Mathematical Sciences Qufu Normal University

Let L be a type II1 factor with separable predual and r be a normal faithful tracial state of c~. We first show that the set of subfactors of L with property F, the set of type II1 subfactors of L with similarity property and the set of all McDuff sub/actors of t are open and closed in the Hausdorff metric d2 induced by the trace norm; then we show that the set of all hyperfinite von Neumann subalgebras of L is closed in d2. We also consider the connection of perturbation of operator algebras under d2 with the fundamental group and the generator problem of type II1 factors. When M is a finite yon Neumann algebra with a normal faithful trace, the set of all von Neumann subalgebras B of M such that B ∪→ M is rigid is closed in the Hausdorff metric d2.

关键词： type II1 factor, property F, McDuff factor, hyperfinite similarity length

Random step maneuver algorithm with normally distributed starting times

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Journal of Systems Engineering and Electronics 2016年第4期27卷 887-891页

作者： liguang wang Lingling wang Information and Navigation College Air Force Engineering UniversityXi'an 710077China Xi'an North Opto-electronic Science and Technology Defense Co.Ltd Xi'an 710043China

The random step maneuver with uniformly distributed starting times has the disadvantage that it cannot focus the starting time on the more efficiency time. It decreases the penetration probability. To resolve this problem, a random step penetration algorithm with normal distribution starting time is proposed. Using the shaping filters and adjoint system method, the miss distance with different starting times can be acquired. According to the penetration standard, the time window ensuring successful penetration can be calculated and it is used as the 3σ bound of the normally distributed random maneuver. Simulation results indicate that the normally distributed random maneuver has higher penetration probability than the uniformly distributed random maneuver.

关键词： random maneuver step maneuver uniform distribution normal distribution

AN ALE METHOD AND DDM WITH HIGH ACCURATE COMPACT SCHEMES FOR VORTEX-INDUCED VIBRATIONS OF AN ELASTIC CIRCULAR CYLINDER

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Journal of Hydrodynamics 2004年第6期16卷 708-715页

作者： RENAn-lu CHENWen-qu liguang-wang DepartmentofMechanics ZhejiangUniversityHangzhou310027China

A numerical study was conducted for the vortex-induced vibrations of anelastic circular cylinder at low Reynolds numbers. An Arbitrary Lagrangian-Eulerian (ALE) method wasemployed to deal with the fluid-structure interaction with an H-O type of non-staggered gridsincorporating the domain decomposition method (DDM), which could save the computational CPU time dueto re-meshing. The computational domain was divided into nine sub-domains including one ALEsub-domain and eight Eulerian sub-domains. The convection term and dissipation term in the N-Sequations were discretized using the third-order upwind compact scheme and the fourth-order centralcompact scheme, respectively. The motion of the cylinder was modeled by a spring-damper-mass systemand solved using the Runge-Kutta method. By simulating the non-linear fluid-structure interaction,the ''lock-in'', ''beating'' and ''phase switch'' phenomena were successfully captured, and the resultsagree with experimental data Furthermore, the vortex structure, the unsteady lift and drag on thecylinder, and the cylinder displacement at various natural frequency of the cylinder for Re = 200were discussed in detail, by which a jump transition of the wake structure was captured.

关键词： arbitrary lagragian-eulerian (ALE) method vortex-induced vibrations domaindecomposition Method (DDM) flow around a circular cylinder compact schemes

Isomorphism of extensions of C(T^2)

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Science China Mathematics 2011年第2期54卷 281-286页

作者： WEI ChangGuo wang liguang School of Mathematical Sciences Ocean University of China Qingdao 266100 China School of Mathematical Sciences Qufu Normal University Qufu 273165 China

In this paper we give a certain classification theorem of extensions of the torus algebra up to isomorphism and also show that the K 0 -group K 0 (E) and the semigroup V (E) are two complete invariants of such extensi... 详细信息

关键词： extension semigroup isomorphism

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基于机器学习的小麦产量预估模型设计与实现

山西电子技术 2024年第4期 57-59页

作者：樊弋鸣王黎光西京学院计算机学院陕西西安710123

2021年政府工作报告中提到“十四五”时期,继续保持粮食综合生产能力在13万亿斤以上,严守18亿亩耕地红线,实施高标准农田建设工程,确保种源安全。基于物联网大数据的小麦产量预估模型设计与实现,对小麦产量预测背景及意义进行了研究,并... 详细信息

2021年政府工作报告中提到“十四五”时期,继续保持粮食综合生产能力在13万亿斤以上,严守18亿亩耕地红线,实施高标准农田建设工程,确保种源安全。基于物联网大数据的小麦产量预估模型设计与实现,对小麦产量预测背景及意义进行了研究,并对小麦产量预估模型进行技术、经济及操作方面的可行性分析,运用数据可视化技术,对近五年小麦在不同环境下的产量进行直观展现,并据此分析出影响小麦产量的主要因素。同时采用LightGBM(简称:LGB)模型和XGBoost(简称:XGB)模型作为关键技术,构建小麦产量预估模型,将预估的小麦产量与实际产量进行比对,误差控制在5 kg之内,具有良好的预测效果。

关键词：产量预测 LGB模型 XGB模型数据可视化

Sulfide-Based All-Solid-State Lithium-Sulfur Batteries:Challenges and Perspectives

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Nano-Micro Letters 2023年第5期15卷 376-386页

作者： Xinxin Zhu liguang wang Zhengyu Bai Jun Lu Tianpin Wu College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310058People’s Republic of China Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and Reactions Ministry of Education School of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan 453007People’s Republic of China

Lithium-sulfur batteries with liquid electrolytes have been obstructed by severe shuttle effects and intrinsic safety *** inorganic solid-state electrolytes into lithium-sulfur systems is believed as an effective approach to eliminate these issues without sacrificing the high-energy density,which determines sulfidebased all-solid-state lithium-sulfur ***,the lack of design principles for high-performance composite sulfur cathodes limits their further *** sulfur cathode regulation should take several factors including the intrinsic insulation of sulfur,well-designed conductive networks,integrated sulfur-electrolyte interfaces,and porous structure for volume expansion,and the correlation between these factors into ***,we summarize the challenges of regulating composite sulfur cathodes with respect to ionic/electronic diffusions and put forward the corresponding solutions for obtaining stable positive *** the last section,we also outlook the future research pathways of architecture sulfur cathode to guide the develop high-performance all-solid-state lithium-sulfur batteries.

关键词： All-solid-state lithium-sulfur battery Sulfur cathode Triple-phase interfaces Electrolyte decomposition Volume change

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轨道交通施工安全管理标准化

黑龙江交通科技 2024年第3期47卷 168-170页

作者：李伟王立广刁浩宇上海轨道交通十五号线发展有限公司上海200063 中国交通建设股份有限公司轨道分公司北京100120 同济大学土木工程学院上海200092

地下轨道交通是城市道路运输体系的重要组成部分,其建设施工环境复杂,施工技术人员水平不一,而以往的施工安全管理主要集中在施工技术方面,涉及个人与单位的责任制度较少,为保障建设安全需以责任制为侧重点,完善并加强地下轨道交通施工... 详细信息

地下轨道交通是城市道路运输体系的重要组成部分,其建设施工环境复杂,施工技术人员水平不一,而以往的施工安全管理主要集中在施工技术方面,涉及个人与单位的责任制度较少,为保障建设安全需以责任制为侧重点,完善并加强地下轨道交通施工安全管理标准化。拟以地下轨道交通施工参与单位的安全管理为研究对象,以标准化和安全管理理论为依据,利用戴明循环基本原理明确安全管理标准化参与单位及担责,以管理流程、管理行为以及管理依据三个创新层级理念阐述地下轨道交通施工安全管理标准化。

关键词：轨道交通标准化安全管理

基于数据感知融合的电力通信网络智能运维方法

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通信电源技术 2024年第15期41卷 55-57页

作者：范洵王文涛姜苏王李光国网江苏省电力有限公司镇江供电分公司江苏镇江212000

电力通信网络作为现代电力系统的神经中枢,其健康稳定运行对于保障电力供应安全至关重要。文章探讨数据感知融合技术的原理及其在电力通信网络中的应用框架,随后详细介绍智能运维的关键步骤,包括数据预处理与质量评估、多源数据融合算... 详细信息

电力通信网络作为现代电力系统的神经中枢,其健康稳定运行对于保障电力供应安全至关重要。文章探讨数据感知融合技术的原理及其在电力通信网络中的应用框架,随后详细介绍智能运维的关键步骤,包括数据预处理与质量评估、多源数据融合算法及异常检测与故障预测,并通过系统测试验证方法的有效性。通过实证研究,展示如何利用先进的数据处理和分析技术,以实现智能化和自动化电力通信网络运维,为提高网络运维效率和减少运维成本提供可靠的技术支持和科学依据。

关键词：数据感知融合电力通信网络智能运维

The effects of span-wise and chord-wise flexibility on the aerodynamic performance of micro flapping-wing

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Chinese Science Bulletin 2012年第22期57卷 2887-2897页

作者： YANG WenQing SONG BiFeng SONG WenPing wang liguang School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

The flexibility of flapping-wing strongly affects the aerodynamic performance of Flapping-wing Micro Air Vehicle (FMAV),and the deformations in span-wise and chord-wise directions are coupled together in *** this study,the flexible deformation is formulated in span-wise and chord-wise separately in order to analyze its effects on aerodynamic *** preconditioned Navier-Stokes equations based on chimera grid are used in the computational fluid dynamics method to study the aerodynamic effects caused by flexible deformation,and the simulation results are compared with experimental test to illustrate the capability of above *** on our results,it is clearly showed that the span-wise flexible deformation should be limited in a small range to achieve higher aerodynamic performance and the chord-wise deformation could enhance the aerodynamic *** results also suggest that FMAV designers should design the flapping-wing with high stiffness leading edge to limit the span-wise deformation,and more flexible chord ribs to keep chord-wise deformation in suitable range.

关键词：空气动力性能微型飞行器弹性变形 Navier-Stokes方程扑翼弦向空气动力学效应空气动力学性能