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基于DPSIR-对称交互熵的泰安市水—城地人产系统协调性评价

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水电能源科学 2024年第5期42卷 80-83,18页

作者：潘慧民门宝辉王红瑞李一阳李永坤王丽晶华北电力大学水利与水电工程学院北京102206 北京师范大学水科学研究院北京100875 北京市水科学技术研究院北京100048

为将四水四定落到实处,构建了基于DPSIR-对称交互熵的水—城地人产系统评价模型,通过构建山东省泰安市评价指标体系,开展协调性发展综合评价,进而建立耦合协调度模型评价各子系统间发展协调性。研究表明,各子系统综合评价值呈现波动上... 详细信息

为将四水四定落到实处,构建了基于DPSIR-对称交互熵的水—城地人产系统评价模型,通过构建山东省泰安市评价指标体系,开展协调性发展综合评价,进而建立耦合协调度模型评价各子系统间发展协调性。研究表明,各子系统综合评价值呈现波动上升趋势,其中状态(S)和响应(R)子系统波动上升趋势最为稳定,最不稳定的为压力(P)子系统;按照历年系统耦合协调度将2006年以来泰安市水—城地人产系统发展划分为过渡阶段(2006~2010年)、协调发展阶段(2011~2019年)、高质量发展阶段(2020年以后);宁阳县、东平县协调度仍有待提高,未来应当着重推进泰安市水网建设、供、用水结构优化和产业结构升级等工作。研究结果可为泰安市国土空间规划及水利高质量发展提供支持。

关键词：四水四定 DPSIR模型对称交互熵耦合协调度模型协调性评价

CuSn10P1合金晶间偏析对拉伸断裂行为的影响及变形机制

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塑性工程学报 2024年第8期31卷 171-178页

作者：刘章兴文科李永坤熊文韬王志杰周荣锋昆明理工大学材料科学与工程学院云南昆明650032 昆明理工大学城市学院云南昆明650051

在室温和拉伸速度1 mm·min^(-1)的条件下,对两种不同晶间偏析程度的CuSn10P1合金进行了单向拉伸试验。结果表明,半固态合金抗拉强度和断后伸长率相比液态合金分别提高30.7%和378.7%。在拉伸过程中,两种材料的裂纹都是沿晶间和α相高锡... 详细信息

在室温和拉伸速度1 mm·min^(-1)的条件下,对两种不同晶间偏析程度的CuSn10P1合金进行了单向拉伸试验。结果表明,半固态合金抗拉强度和断后伸长率相比液态合金分别提高30.7%和378.7%。在拉伸过程中,两种材料的裂纹都是沿晶间和α相高锡过渡层扩展,但是半固态CuSn10P1合金具有更优异的力学性能。这主要归因于半固态CuSn10P1合金具有较少的晶间组织、更细小的晶粒尺寸和更高的Sn元素固溶度。断裂后,在半固态CuSn10P1合金的α相高锡过渡层区域发现了变形孪晶,说明其变形机制由滑移机制向孪生机制转变。

关键词： CuSn10P1合金晶间偏析断裂行为变形机制

Oscillation Criteria for Impulsive Hyperbolic Equations of Neutral Type

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Chinese Quarterly Journal of Mathematics 2006年第2期21卷 176-184页

作者： ZHU Xian-yang li yong-kun LU ling-hong Department of Mathematics Yunnan University Kunming 650091 China Department of Mathematics Shanghai University Shanghai 200436 China

Oscillation properties of the solutions of impulsive hyperbolic equations are investigated by the method of differential inequalities.

关键词： oscillation hyperbolic equation impulsive boundary value problem

Two Positive Periodic Solutions of Delay Functional Difference System with Feedback Control

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Chinese Quarterly Journal of Mathematics 2009年第1期24卷 102-107页

作者： GUO Peng-fei ZHU Xian-yang li yong-kun Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Department of Mathematics Lianyungang Teachers College Lianyungang 222006 China Department of Mathematics Shanghai University Shanghai 200444 China Department of Mathematics Yunnan University Kunming 650091 China

By using a fixed point theorem on a cone to investigate the existence of two positive periodic solutions for the following delay difference system with feedback control argument of the form {△x（n）=-b（n）x（n）＋f（n,x（n-τ1（n））,…,x（n-τm（n））,u（n-δ（n）））,△u（n）=-η（n）u（n）＋a（n）x（n-σ（n））,n∈Z.

关键词： delay difference system positive periodic solution feedback control fixed pointtheorem

GLOBAL ATTRACTIVITY IN A PERIODIC DELAY SINGLE SPECIES MODEL

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Systems Science and Mathematical Sciences 2000年第1期13卷 1-6页

作者： li yong kun (Department of Mathematics, Yunnan University, kunming 650091, China) 云南大学数学系云南昆明 650091

***[1]illtroducedthefollowingdelayLotka-Volterratypesinglespeciespopulationgrowthmodel:wherea,b,ctTarerealconstants,anda>0,c>0,***>0,b0,(l.1)exhibitstheso--calledAlic... 详细信息

***[1]illtroducedthefollowingdelayLotka-Volterratypesinglespeciespopulationgrowthmodel:wherea,b,ctTarerealconstants,anda>0,c>0,***>0,b0,(l.1)exhibitstheso--calledAlic...

关键词： Single species population growth positive periodic solution global attractivity foedholm mapping.

Oscillation of Second-order Delay Differential Equation

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Chinese Quarterly Journal of Mathematics 2004年第1期19卷 30-34页

作者： YINFu-qi liyong-kun DepartmentofMathematics YunnanUniversityKunming650091China DepartmentofMathematics YunnanUniversityKunming650091China

By using some differential inequality, a second-order delay differential equation(r(t)x′(t))′ + p(t)x(q(t)) = 0has been investigated and some necessary condition for this equation has a nonoscillatorysolution and so... 详细信息

关键词： differential equation delay oscillation differential inequality

Review on regulation of MnS in non-qquenched and tempered steel

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Journal of Iron and Steel Research International 2024年第4期31卷 779-789页

作者： Guo-xing Qiu Qing Du Feng Lu De-jun Miao yong-kun Yang Xiao-ming li School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina Laigang Technique Center Shandong Iron and Steel Group Co.Ltd.Jinan 271104ShandongChina

An overview of the current research status and control methods of MnS in non-quenched and tempered steel was *** a low-melting plastic inclusion,the morphology and distribution of MnS were influenced by various production ***,control of MnS is a systematic problem that must be integrated into the entire production *** on the production process,the factors affecting the morphology and distribution of MnS in steel were *** effects of oxygen activity,manganese,sulfur,and some alloys on MnS inclusion precipitation were summarized,mainly including MnS modification treatment and oxygen-sulfide composite precipitation *** is believed that MnS precipitates during the solidification process of steel,and controlling the solidification cooling rate could effectively regulate the size and morphology of MnS,avoiding the precipitation of ***,by changing the deformation rate,deformation amount,deformation temperature during the hot deformation process,and heating time and temperature during heat treatment,the distribution and morphology of MnS could be *** the fine control of the above process parameters,the number of II-MnS in steel could be effectively reduced,and their morphology could be improved,thereby enhancing the performance of non-quenched and tempered steel and promoting its wider ***,applying laboratory research results to industrial production is an important direction for future research efforts in this field.

关键词： MnS Non-quenched and tempered steel Control technology Process parameter Morphology Distribution

Adaptive Consensus of Uncertain Multi-Agent Systems With Unified Prescribed Performance

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1310-1312页

作者： kun li Kai Zhao yongduan Song The authors are with the School of Automation Chongqing UniversityChongqing 400044China

Dear Editor,An adaptive consensus control algorithm for uncertain multi-agent systems(MAS),capable of guaranteeing unified prescribed performance,is presented in this *** many existing prescribed performance related works,the developed control exhibits some ***,a distributed prescribed time observer is introduced so that not only each follower is able to estimate the leader’s signal within a predetermined time,but also the control design for each agent is independent with its neighbors.

关键词： agent prescribed Uncertain

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： yong-Zhi lin Lu-kun Feng Ya-Dong li Chao-Fan Chang Cai-Zhen Zhu Ming-liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT