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A novel triple periodic minimal surface-like plate lattice and its data-driven optimization method for superior mechanical properties

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 217-238页

作者： Yanda wang Yanping LIAN Zhidong wang Chunpeng wang Daining FANG State Key Laboratory for Turbulence and Complex Systems&Center for Applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM)*** this work,a novel design of plate lattice structures described by a parametric model is proposed to enrich the design space of plate lattice structures with high connectivity suitable for AM *** parametric model takes the basic unit of the triple periodic minimal surface(TPMS)lattice as a skeleton and adopts a set of generation parameters to determine the plate lattice structure with different topologies,which takes the advantages of both plate lattices for superior specific mechanical properties and TPMS lattices for high connectivity,and therefore is referred to as a TPMS-like plate lattice(TLPL).Furthermore,a data-driven shape optimization method is proposed to optimize the TLPL structure for maximum mechanical properties with or without the isotropic *** this method,the genetic algorithm for the optimization is utilized for global search capability,and an artificial neural network(ANN)model for individual fitness estimation is integrated for high efficiency.A set of optimized TLPLs at different relative densities are experimentally validated by the selective laser melting(SLM)fabricated *** is confirmed that the optimized TLPLs could achieve elastic isotropy and have superior stiffness over other isotropic lattice structures.

关键词： lattice structure triple periodic minimal surface(TPMS) plate lattice structural optimization machine learning

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数字地形图测绘中的修测方法探讨

城市勘测 2007年第5期 106-108页

作者：倪锡春王世亮德清县城乡测绘所浙江德清313200 浙江煤炭测绘院浙江杭州310000

结合工作中实际例子,介绍修测方法在解决数字地形图更新问题中的具体应用及注意事项。

关键词：数字地形图地形图更新机制原图质量修测方案

Multiple-stage spatial-temporal cooperative guidance without time-to-go estimation

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Chinese Journal of Aeronautics 2024年第9期37卷 399-416页

作者： Chunyan wang Weilin wang Wei DONG Jianan wang Fang DENG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China National Key Lab of Autonomous Intelligent Unmanned Systems Beiing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

This paper investigates the spatial-temporal cooperative guidance problem for multiple flight vehicles without relying on time-to-go ***,a two-stage cooperative guidance strategy,namely the cooperative guidance and the Proportional Navigation Guidance(PNG)stage strategy,is developed to realize the spatial-temporal constraints in two *** the former stage,two controllers are designed and superimposed to satisfy both impact time consensus and impact angle *** the convergent conditions are satisfied,the flight vehicles will switch to the PNG stage to ensure zero miss *** further extend the results to three dimensions,a planar pursuit guidance stage is additionally imposed at the beginning of *** to the inde-pendence of time-to-go estimation,the proposed guidance strategy possesses great performance in satisfying complex spatial-temporal constraints even under flight speed ***,several numerical simulations are implemented to verify the effectiveness and advantages of the proposed results under different scenarios.

关键词： Cooperative guidance Guided missiles Impact time consensus Impact angle constraint Spatial-temporal cooperative guidance

根深足稳方扎实--谈农村小学语文课堂作业的有效设计

维普期刊数据库评论

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维普期刊数据库

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科教文汇 2016年第33期 97-98页

作者：陈丽君王士良阜阳市颍泉区实验小学安徽阜阳236000 阜阳市颍泉区四九小学安徽阜阳236000

减负增效是课堂作业设计的出发点和落脚点,语文课堂作业力求冲出"题海"的围城,让学生轻松愉快地学习。这就需要在"有效"上下功夫,努力实现作业设计的多样性、趣味性、创新性,尽量达到作业的多元统一,并有一定导航课堂教学的功能。双基... 详细信息

减负增效是课堂作业设计的出发点和落脚点,语文课堂作业力求冲出"题海"的围城,让学生轻松愉快地学习。这就需要在"有效"上下功夫,努力实现作业设计的多样性、趣味性、创新性,尽量达到作业的多元统一,并有一定导航课堂教学的功能。双基训练总要落实在课堂教学之中,一定通过作业的设计达成效果。

关键词：课堂作业有效设计根本立足点

Adaptive Barrier-Lyapunov-Functions Based Control Scheme of Nonlinear Pure-Feedback Systems with Full State Constraints and Asymptotic Tracking Performance

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Journal of Systems Science & Complexity 2024年第3期37卷 965-984页

作者： NIU Ben wang Xiaoan wang Xiaomei wang Xinjun LI Tao Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian 116024China School of Information Science and Engineering Shandong Normal UniversityJinan 250014China School of Mathematics Southeast UniversityNanjing 211189China School of Automation Nanjing University of Information Science and TechnologyNanjing 210044China

In this paper,the authors propose an adaptive Barrier-Lyapunov-Functions(BLFs)based control scheme for nonlinear pure-feedback systems with full state *** to the coexist of the non-affine structure and full state constraints,it is very difficult to construct a desired controller for the considered *** to the mean value theorem,the authors transform the pure-feedback system into a system with strict-feedback structure,so that the well-known backstepping method can be ***,in the backstepping design process,the BLFs are employed to avoid the violation of the state constraints,and neural networks(NNs)are directly used to online approximate the unknown packaged nonlinear *** presented controller ensures that all the signals in the closed-loop system are bounded and the tracking error asymptotically converges to ***,it is shown that the constraint requirement on the system will not be violated during the ***,two simulation examples are provided to show the effectiveness of the proposed control scheme.

关键词： Asymptotic tracking control barrier Lyapunov functions full state constraints nonlinear pure-feedback systems

The Coarse l^(p)-Novikov Conjecture and Banach Spaces with Property(H)

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 193-220页

作者： Huan wang Qin wang Research Center for Operator Algebras School of Mathematical SciencesEast China Normal UniversityShanghai 200241China Key Laboratory of MEA Ministry of Educationand Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China

In this paper,for 1

关键词： The coarse l^(p)-Novikov conjecture Banach spaces with Property(H) Coarse geometry K-Theory

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臭氧催化氧化-活性炭吸附处理DDNP废水

爆破器材 2014年第4期43卷 52-56页

作者：王时亮杨爱江李清吴欣琪贵州大学资源与环境工程学院贵州贵阳550025 贵州大学环境工程规划设计研究所贵州贵阳550025 梧州龙达环保工程有限公司广西梧州543000

采用臭氧催化氧化．活性炭吸附方法处理DDNP废水，与单独臭氧氧化相比，催化剂的加入可以提高反应后期酸性环境下臭氧的氧化效率。试验选用Fe-活性炭催化组合，在曝气量为70L／min，臭氧质量浓度为11．5mg/L的情况下处理500mL废水，1h... 详细信息

采用臭氧催化氧化．活性炭吸附方法处理DDNP废水，与单独臭氧氧化相比，催化剂的加入可以提高反应后期酸性环境下臭氧的氧化效率。试验选用Fe-活性炭催化组合，在曝气量为70L／min，臭氧质量浓度为11．5mg/L的情况下处理500mL废水，1h后废水中COD、色度、硝基酚类化合物去除率分别达到72．6％、94．3％、80．6％；活性炭吸附处理臭氧催化氧化后DDNP废水可达到《兵器工业水污染排放标准》。当活性炭饱和导致水质超标时，采用臭氧对活性炭进行再生20min，经反复10次试验，出水水质中COD稳定在131．47～152．96mg/L，色度和硝基酚类化合物的含量低于排放标准，处理效果良好，具有可重复性。

关键词： DDNP 催化剂臭氧催化氧化活性炭吸附活性炭再生

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从冷藏箱的双剂更新看全球气候变暖

集装箱化 2006年第3期17卷 31-32页

作者：关慎谦王世良交通部水运科学研究院上海中集冷藏集装箱有限公司

1 全球气候变暖已成现实鉴于对臭氧层的破坏力(Ozone Depletion Potential,ODP)和地球表面的温室效应(Global Warming Potential,GWP),联合国环境规划署(UNDP--United Nations Environment Program)于1992年在丹麦首都哥本哈根和以后在蒙特利尔召开的会议上,对严重破坏大气中臭氧层的介质(Ozone Depleting Substances)CFC冷剂和发泡剂给予严格限制并规定了具体的禁用期限.

关键词：全球气候变暖冷藏箱联合国环境规划署更新温室效应地球表面蒙特利尔哥本哈根臭氧层破坏力

Performance and Application of Double-layered Microcapsule Corrosion Inhibitors

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 845-853页

作者：余海燕 wang Yingxiang wang Ruizhi HU Lintong wang Tianlei School of Materials Science and Engineering Tianjin Chengjian UniversityTianjin 300384China Tianjin Key Laboratory of Building Green Functional Materials Tianjin Chengjian UniversityTianjin 300384China

Double-layered microcapsule corrosion inhibitors were developed by sodium monofluorophosphate as the core material,polymethyl methacrylate as the inner wall material,and polyvinyl alcohol as the outer wall material combining the solvent evaporation method and spray drying *** protection by the outer capsule wall was used to prolong the service life of the corrosion *** dispersion,encapsulation,thermal stability of microcapsules,and the degradation rate of capsule wall in concrete pore solution were analyzed by ultra-deep field microscopy,scanning electron microscopy,thermal analyzer,and sodium ion release rate *** microcapsules were incorporated into mortar samples containing steel reinforcement,and the effects of double-layered microcapsule corrosion inhibitors on the performance of the cement matrix and the actual corrosion-inhibiting effect were *** experimental results show that the double-layered microcapsules have a moderate particle size and uniform distribution,and the capsules were completely *** microcapsules as a whole have good thermal stability below 230 ℃.The monolayer membrane structure microcapsules completely broke within 1 day in the simulated concrete pore solution,and the double-layer membrane structure prolonged the service life of the microcapsules to 80 days in the simulated concrete pore solution before the core material was completely *** mortar samples containing steel reinforcement incorporated with the double-layered microcapsule corrosion inhibitors still maintained a higher corrosion potential than the monolayer microcapsule corrosion inhibitors control group at 60 *** incorporation of double-layered microcapsules into the cement matrix has no significant adverse effect on the setting time and early strength.

关键词： corrosion inhibitors microcapsule double-layer structure potentiodynamic polarization curve