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Toward tunable shape memory effect of NiTi alloy by grain size engineering:A phase field study

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Journal of Materials Science & Technology 2024年第1期168卷 276-289页

作者： Bo Xu Chong wang Qingyuan wang Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Department of Mechanical Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering (Sichuan University)Ministry of EducationChengdu 610065China

The inelastic deformations of shape memory alloys(SMAs)always show poor controllability due to the avalanche-like martensite transformation,and the effective control for the deformation of precision de-vices has been not yet *** this work,the phase field method was used to investigate the shape memory effects(SMEs)of NiTi SMAs undergoing grain size(GS)engineering,to obtain tunable one-way and stress-assisted two-way SMEs(OWSME and SATWSME).The OWSME and SATWSME of the systems with various gradient-nanograin structures and bimodal grain structure,as well as that with geometric gradients were *** simulated results indicate that due to the GS dependences of martensite transformation and reorientation,the occurrence and expansion of martensite reorientation,martensite transformation and its reverse can be efficaciously controlled via the GS *** combining the GS engineering and geometric gradient design,since the effects of GS and stress gradient can be su-perimposed or competing,and the responses of martensite reorientation,martensite transformation and its reverse to this are different,the OWSME and SATWSME of the geometrically graded systems with various nanograin structures can exhibit different improvements in *** short,the reorienta-tion hardening modulus during OWSME is increased and the transformation temperature window during SATWSME is widened by GS engineering,indicating the improved controllability of *** optimal GS engineering schemes revealed in this work provide the basic reference and guidance for designing tun-able SMEs and producing NiTi-based driving devices catering to desired functional performance in various engineering fields.

关键词： Phase field NiTi Shape memory effect Grain size engineering Geometric gradient

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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海洋微藻总脂含量和脂肪酸组成的测定

中国油脂 2008年第11期33卷 67-70页

作者：王明清迟晓元秦松杨官品姜鹏逄少军中国海洋大学海洋生命学院山东青岛266003 中国科学院海洋研究所山东青岛266071 中国科学院研究生院北京100039

对14株海洋微藻（绿藻纲6株，金藻纲4株，硅藻纲3株，甲藻纲1株）中的总脂含量和脂肪酸成分进行了测定。结果表明，14株海洋微藻的总脂含量存在着明显差异，盐藻的总脂含量最高，占千重的28．71％；4株金藻的总脂含量均较高，超过干重... 详细信息

对14株海洋微藻（绿藻纲6株，金藻纲4株，硅藻纲3株，甲藻纲1株）中的总脂含量和脂肪酸成分进行了测定。结果表明，14株海洋微藻的总脂含量存在着明显差异，盐藻的总脂含量最高，占千重的28．71％；4株金藻的总脂含量均较高，超过干重的20％。14株海洋微藻的脂肪酸成分和含量也存在着较大的差异，绿藻中饱和脂肪酸C16：0。的含量均较高；对于单不饱和脂肪酸，小球藻以C16：1（n=7）为主，盐藻以C18：1（n=7）为主，青岛大扁藻以C18：1（n=9）为主。4株金藻的PUFAs含量均较高，几乎占脂肪酸总量的1／2，并且DHA的含量较其他藻株高。3．株硅藻的EPA含量最高，占27．2％-32．9％；而裸甲藻的PUFAs含量最低，仅为25．2％。

关键词：海洋微藻总脂脂肪酸多不饱和脂肪酸

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项目管理理论在市政工程管理中的应用

工程技术研究 2023年第20期8卷 135-137页

作者：朱康萌王越王铭庆中国市政工程中南设计研究总院有限公司湖北武汉430000

市政项目管理具有多专业、多工种的特征,将项目管理理论贯穿市政项目全过程,能加强对各要素的综合管控,有利于施工项目的协调发展,从而达到安全生产和高效施工的目的。文章阐述了项目管理的内涵和特点,明确了市政工程管理工作的必要性,... 详细信息

市政项目管理具有多专业、多工种的特征,将项目管理理论贯穿市政项目全过程,能加强对各要素的综合管控,有利于施工项目的协调发展,从而达到安全生产和高效施工的目的。文章阐述了项目管理的内涵和特点,明确了市政工程管理工作的必要性,分析了当前市政工程管理环节仍存在的制度松散、现场管理工作不全面、管理积极性不高的问题,从完善管理机构、施工材料和设备管理、施工环境管理、安全管理、成本管理、人员管理方面叙述了项目管理理论在市政工程管理中的应用,旨在提高市政工程管理水平。

关键词：项目管理理论市政工程安全管理成本管理

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

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印刷厂在色彩管理中的难点

办公自动化 2015年第7期20卷 61-62页

作者：李贺田王明清北京信息职业技术学院北京100070

随着印刷技术的不断发展,色彩管理技术也得到了快速发展。很多印刷厂纷纷实行色彩管理技术,这不仅有利于印刷质量的提高,还有利于印刷厂整体效率的提高。但是现代印刷厂在实施色彩管理的时候往往还存在很多难点,分析和设计具有针对性的... 详细信息

随着印刷技术的不断发展,色彩管理技术也得到了快速发展。很多印刷厂纷纷实行色彩管理技术,这不仅有利于印刷质量的提高,还有利于印刷厂整体效率的提高。但是现代印刷厂在实施色彩管理的时候往往还存在很多难点,分析和设计具有针对性的解决方案成为现代印刷界一个热点问题。

关键词：色彩管理问题印刷厂

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

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

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： wang, Chunyan wang, Weilin Dong, Wei wang, Jianan Deng, Fang Beijing Inst Technol Sch Aerosp Engn Beijing 100081 Peoples R China Beijing Inst Technol Natl Key Lab Autonomous Intelligent Unmanned Syst Beijing 100081 Peoples R China Beijing Inst Technol Chongqing Innovat Ctr Chongqing 401120 Peoples R China

This paper investigates the spatial-temporal cooperative guidance problem for multiple flight vehicles without relying on time-to-go information. First, 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 dimensions. At the former stage, two controllers are designed and superimposed to satisfy both impact time consensus and impact angle constraints. Once the convergent conditions are satisfied, the flight vehicles will switch to the PNG stage to ensure zero miss distance. To further extend the results to three dimensions, a planar pursuit guidance stage is additionally imposed at the beginning of guidance. Due to the independence of time-to-go estimation, the proposed guidance strategy possesses great performance in satisfying complex spatial-temporal constraints even under flight speed variation. Finally, several numerical simulations are implemented to verify the effectiveness and advantages of the proposed results under different scenarios. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Cooperative guidance Guided missiles Impact time consensus Impact angle constraint Spatial-temporal cooperative guidance SLIDING-MODE CONTROL IMPACT-TIME SALVO ATTACK ANGLE-CONTROL LAW MISSILES