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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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A triblock copolymer electrolyte with quadruple hydrogen bonds enables high-performance solid-state lithium-metal batteries
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作者 GUO Nan WANG Xinyu +4 位作者 HE Yuxin ZHANG Yu YU Jiaye LI Xin FENG Jingdong 《分子科学学报》 2025年第3期22-29,共8页
The development of high-performance solid-state electrolytes(SSEs)capable of reconciling high ionic conductivity with robust mechanical strength is crucial for advancing safe lithium-metal batteries(LMBs).In this stud... The development of high-performance solid-state electrolytes(SSEs)capable of reconciling high ionic conductivity with robust mechanical strength is crucial for advancing safe lithium-metal batteries(LMBs).In this study,we synthesized a novel BAB-type triblock copolymer PuPyMA-b-PEO-b-PuPyMA and used it to prepare SSEs.The copolymer design incorporates polyethylene oxide(PEO)segments to achieve ionic conduction,while uracil ketone(uPy)groups are introduced to provide quadruple hydrogen bonding.This molecular architecture leverages microphase separation and supramolecular interactions to optimize performance.The optimized electrolyte,PPMP-30 with w(uPyMA)=30%,n(EO)/n(Li^(+))=25/1,exhibits outstanding comprehensive properties at room temperature:an ionic conductivity of 4.0×10^(-4)S·cm^(-1),a high Li^(+)transference number of 0.41,and an extended electrochemical stability window up to 5.6 V(vs.Li^(+)/Li).Li//Li symmetric cells demonstrate exceptional interfacial stability and lithium dendrite suppression,cycling stably for over 650 h at 0.05 mA·cm^(-2).When assembled into LiFePO_(4)//Li cells,the electrolyte enables a high initial discharge capacity(about 160 mAh·g^(-1)at 0.1 C),excellent cycling stability(85.0%capacity retention after 120 cycles),and good rate capability with significant capacity recovery upon returning to low rates.These results highlight the significant potential of this tetrahedral hydrogen-bonded block copolymer electrolyte in overcoming the ionic conductivity-mechanical strength trade-off for practical solid-state LMBs. 展开更多
关键词 solid polymer electrolytes triblock copolymer quadruple hydrogen bonding ionic conductivity solid-state lithiummetal batteries
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Effects of College Students’ Perceived Stress on Anxiety in the Time of COVID-19: The Chain Mediation Role of Psychological Resilience and Regulatory Emotional Self-Efficacy 被引量:4
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作者 Ting Li Qiang Xie 《International Journal of Mental Health Promotion》 2022年第2期263-276,共14页
COVID-19 has changed the way of learning and life of college students.The purpose is to explore the relationship between perceived stress and anxiety,and the mediating effect of resilience and regulatory emotional sel... COVID-19 has changed the way of learning and life of college students.The purpose is to explore the relationship between perceived stress and anxiety,and the mediating effect of resilience and regulatory emotional self-efficacy in college students during COVID-19.309 students from three colleges were selected as research participants(average age 19.79±1.11 years).SPSS was used to measure the correlation between variables.Amos was used to test the path coefficient and mediating effect of the hypothetical model.The results show that:Firstly,perceived stress has a significantly and positively predictive effect on anxiety.Secondly,psychological resilience and regu-latory emotional self-efficacy independently played a significant and partially mediating effect between perceived stress and anxiety.Among them,perceived stress had a negative predictive effect on psychological resilience and regulatory emotional self-efficacy.Psychological resilience and regulatory emotional self-efficacy had a negative predictive effect on anxiety.Thirdly,psychological resilience and regulatory emotional self-efficacy play a chain mediation role between psychological stress and anxiety.Regulatory emotional self-efficacy cannot only directly predict the level of anxiety,but also indirectly predict the level of anxiety by regulating psychological resilience.This study reveals the relationship between college students’perceived stress and anxiety,and the mediating effect of psychological resilience and regulatory emotional self-efficacy in the new time of COVID-19.The chain mediation role of psychological resilience and regulatory emotional self-efficacy reminds college mental health educators that improving students’regulatory emotional self-efficacy is an important way to promote students’mental health. 展开更多
关键词 Perceived stress regulatory emotional self-efficacy psychological resilience ANXIETY
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Effects of residual plastic film on crop yield and soil fertility in a dryland farming system 被引量:3
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作者 WANG Dong XI Yue +7 位作者 SHI Xiao-yan GUO Chao-li ZHONG Yu-jie SONG Chao GUAN Yu HUANG Lu YANG Qi-feng LI Feng-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第12期3783-3791,共9页
Plastic film mulch in agricultural production becomes essential to maintaining crop yields in arid and semiarid areas.However,the presence of residual film in farmland soil has also drawn much attention.In this study,... Plastic film mulch in agricultural production becomes essential to maintaining crop yields in arid and semiarid areas.However,the presence of residual film in farmland soil has also drawn much attention.In this study,three experiments were conducted.The first two experimental designs included 0,450,1350,and 2700 kg ha^(-1) of residual film pieces of approximately 5 cm side length added to field soil(0-20 cm soil depth)for seven years and added to pots for four years.In the third experiment,1350 kg ha^(-1)of the residual film with different side lengths(2-5,5-10,10-15,and 15-20 cm)was added to field soil for six years to explore the effect of residual film fragment size on soil nutrients,soil microorganisms,crop growth and yields.The residual film had little effect on the soil moisture at a field depth of 0-2(or 0-1.8)m.There were no significant effects on organic carbon,total nitrogen,inorganic nitrogen,total phosphorus or available phosphorus in the 0-20 cm soil layer.The presence of residual film decreased the richness and diversity of the bacterial community of the surface soil of the residual film,but it had no significant effect on the microbial community of the non-surface soil.The emergence rates of wheat and lentils occasionally decreased significantly with different amounts of residue fragments added to the field.At 450-2700 kg ha^(-1),the residual film reduced the plant height and stem diameter of maize and significantly reduced the shoot biomass of harvested maize by 11-19%.The average yields of maize and potato over the seven years decreased,but there were almost no significant statistical differences among the treatments.These results provide important data for a comprehensive scientific understanding of the effects of residual film on soil and crops in dryland farming systems. 展开更多
关键词 residual film soil nutrients microbial community crop yield
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The Optimization Study of General Education Practice Effect in Our Country 被引量:1
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作者 Liu Jie 《学术界》 CSSCI 北大核心 2013年第12期283-290,共8页
General education has become more and more attention.The culture has a more long-term and lasting contribution,so more and more colleges and universities have adopted a series of reform measures.Effect of the practice... General education has become more and more attention.The culture has a more long-term and lasting contribution,so more and more colleges and universities have adopted a series of reform measures.Effect of the practice of general education,however,still cannot satisfactory.In this paper,main factors affecting was analyzed on the basis of extensive research and questionnaire data analysis and targeted put forward the optimization effect of general education.It is important to make every effort to make the general education in China to achieve"Phoenix Nirvana". 展开更多
关键词 教育实践 优化 通识教育 影响因素 数据分析 调查问卷 大学
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Implement of the Production Monitoring and Control System for Coning,Drawing and Twisting's Workshop
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作者 邵景峰 李永刚 +2 位作者 张奎 李波 李佳 《Journal of Donghua University(English Edition)》 EI CAS 2010年第5期687-693,共7页
To achieve the production information management of the coning,drawing and twisting's workshop,and promote a good and fast development of the textile enterprise,firstly,we analyze the information technology develo... To achieve the production information management of the coning,drawing and twisting's workshop,and promote a good and fast development of the textile enterprise,firstly,we analyze the information technology development status of the textile enterprise at home and abroad,study the weaknesses of the existing computer monitoring system,introduce the system design project,and propose a system network model based on client/server(C/S)mode.Secondly,a multi-agent production monitoring and control system is developed,and the communication of the single-port-multi-protocol and a multi-thread data collection technology are studied via the multi-thread and standard template library(STL)technologies.Thirdly,the system management functions,the structure design of the database,and the technical difficulties in the process of software design are also introduced.As proved in practice,the system satisfies the production management requirements of the workshop,and implements the network management of the production information. 展开更多
关键词 monitoring system CONING drawing and twisting's workshop communication MULTI-THREAD client/server(C/S)
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Process Planning and Scheduling Integration in an Open Manufacturing Environment
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作者 娄平 刘泉 +2 位作者 周祖德 全书海 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2009年第2期177-182,共6页
New open manufacturing environments have been proposed aiming at realizing more flexible distributed manufacturing paradigms,which can deal with not only dynamic changes in volume and variety of products,but also chan... New open manufacturing environments have been proposed aiming at realizing more flexible distributed manufacturing paradigms,which can deal with not only dynamic changes in volume and variety of products,but also changes of machining equipments,dispersals of processing locations,and also with unscheduled disruptions.This research is to develop an integrated process planning and scheduling system,which is suited to this open,dynamic,distributed manufacturing environment.Multi-agent system(MAS)approaches are used for integration of manufacturing processing planning and scheduling in an open distributed manufacturing environment,in which process planning can be adjusted dynamically and manufacturing resources can increase/decrease according to the requirements.One kind of multi-level dynamic negotiated approaches to process planning and scheduling is presented for the integration of manufacturing process planning and scheduling. 展开更多
关键词 multi-agent systems production scheduling process planning integrution negotialtion
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A Desperate Housewife in 1955——An Analysis of Cat on a Hot Tin Roof
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作者 上官潇潇 《海外英语》 2012年第6X期188-190,共3页
Cat on a Hot Tin Roof,written by Tennessee Williams in 1955,is a brilliant play about a dysfunctional family.In this play,Williams uses his craft to entertain,enlighten and bare men's soul in morden society.By ana... Cat on a Hot Tin Roof,written by Tennessee Williams in 1955,is a brilliant play about a dysfunctional family.In this play,Williams uses his craft to entertain,enlighten and bare men's soul in morden society.By analyzing its major characters,themes and symbols,this paper tries to show this play's contemporary significance. 展开更多
关键词 CAT on a Hot Tin ROOF MAJOR CHARACTERS themes symb
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Adaptive learning path recommendation model for examination-oriented education
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作者 Wang Jian Qiao Kuoyuan +2 位作者 Yuan Yanlei Liu Xiaole Yang Jian 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2022年第4期77-88,共12页
Adaptive learning paths provide individual learning objectives that best match a learner’s characteristics.This is especially helpful when learners need to balance limited available learning time and multiple learnin... Adaptive learning paths provide individual learning objectives that best match a learner’s characteristics.This is especially helpful when learners need to balance limited available learning time and multiple learning objectives.The automatic generation of personalized learning paths to improve learning efficiency has therefore attracted significant interest.However,most current research only focuses on providing learners with adaptive objects and sequences according to their own interests or learning goals given a normal amount of time or ordinary conditions.There is little research that can help learners to obtain the most important knowledge for a test in the shortest time possible,which is a typical scenario in exanimation-oriented education systems.This study aims to solve this problem by introducing a new approach that builds on existing methods.First,the eight properties in Gardner’s multiple intelligence theory are introduced into the present knowledge and learner models to define the relationship between learning objects(LOs)and learners,thereby improving recommendation accuracy rates.Then,a novel adaptive learning path recommendation model is presented where viable knowledge topologies,knowledge bases and the previously-established properties relating to a learner’s ability are combined by Dempster-Shafer(D-S)evidence theory.A series of practical experiments were performed to assess the approach’s adaptability,the appropriateness of the selected evidence and the effectiveness of the recommendations.In the results,it was found that the proposed learning path recommendation model helped learners learn the most important elements and obtain superior test grades when confronted with limited time for learning. 展开更多
关键词 adaptive learning learning path recommendation Dempster-Shaferevidence theory knowledge model learner model
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