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Approximation Algorithm for the Balanced 2-Correlation Clustering Problem

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Tsinghua Science and Technology 2022年第5期27卷 777-784页

作者： Sai Ji Dachuan Xu Donglei Du Ling Gai zhongrui zhao Department of Operations Research and Information Engineering Beijing University of TechnologyBeijing 100124China Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China Faculty of Business Administration University of New BrunswickFrederictonNB E3B 5A3Canada Glorious Sun School of Business and Management Donghua UniversityShanghai 200051China

The Correlation Clustering Problem(CorCP) is a significant clustering problem based on the similarity of *** has significant applications in different fields,such as machine learning,biology,and data mining,and many different problems in other *** this paper,the Balanced 2-CorCP(B2-CorCP) is introduced and examined,and a new interesting variant of the CorCP is *** goal of this clustering problem is to partition the vertex set into two clusters with equal size,such that the number of disagreements is *** first present a polynomial time algorithm for the B2-CorCP on M-positive edge dominant graphs(M≥ 3).Then,we provide a series of numerical experiments,and the results show the effectiveness of our algorithm.

关键词： balanced clustering k-correlation clustering positive edge dominant graphs approximation algorithm

Theoretical Study on the Kinetics for the Reactions of Heptyl Radicals with Methanol

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Chemical Research in Chinese Universities 2018年第5期34卷 786-791页

作者： zhao zhongrui SONG Jinou SU Boyang WANG Xiaowen State Key Laboratory of Engines Tianjin University Tianjin 300072 R R. China

Ab initio study of the reactions ofn-heptyl radicals（1-C7H15, 2-C7H15, 3-C7H15, and 4-C7H15） with metha- nol was conducted over the temperature range of 300--1500 K. Transition states for the reaction channels producing CTH15OH, CH3, C7H15OCH3, H, C7H16, CH2OH and CH30 were identified and the geometries of all stationary points were calculated at BB1K/MG3S level of theory. The potential barrier heights of the corresponding transition states were predicted by the CBS-QB3//BB1K and G4//BB1K methods, indicating that the eight H-abstraction channels are more kinetically favorable than the channels where OH transfers from CH3OH to C7H15 and where the CTHIsOCH3＋H products are given. Tile rate constants of H-abstraction channels were calculated with TST and TST/Eck. Both the forward and reverse rate constants have positive temperature dependence and the ttmneling effect is only important at the temperature lower than 700 K. For the reactions of H-atom abstraction from methyl in CH3OH by n-heptyl, a reverse and the corresponding forward rate constant are roughly equal. For the reactions of H-atom abstraction from OH in CH3OH by n-heptyl, a reverse rate constant is larger by several orders of magnitude thin1 the corresponding forward one.

关键词： n-Heptane Methanol Ab initio calculation Conventional transition state theory Tunneling effect

Short-term solar eruptive activity prediction models based on machine learning approaches:A review

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Science China Earth Sciences 2024年第12期67卷 3727-3764页

作者： Xin HUANG zhongrui zhao Yufeng ZHONG Long XU Marianna B.KORSÓS R.ERDÉLYI Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Beijing Cellular Exploration Science and Technology Center Beijing 100190China Dipartimento di Fisica e Astronomia“Ettore Majorana” Universitàdi CataniaCatania I 95123Italy Department of Astronomy Eötvös Loránd UniversityBudapest H-1112Hungary Hungarian Solar Physics Foundation Gyula H-5700Hungary Solar Physics&Space Plasma Research Center(SP2RC) School of Mathematics and StatisticsUniversity of SheffieldSheffield S37RHUK

Solar eruptive activities,mainly including solar flares,coronal mass ejections(CME),and solar proton events(SPE),have an important impact on space weather and our *** short-term solar eruptive activity prediction is an active field of research in the space weather ***,statistical,and machine learning methods are proposed to build prediction models of the solar eruptive *** the development of space-based and ground-based facilities,a large amount of observational data of the Sun is accumulated,and data-driven prediction models of solar eruptive activities have made a significant *** this review,we briefly introduce the machine learning algorithms applied in solar eruptive activity prediction,summarize the prediction modeling process,overview the progress made in the field of solar eruptive activity prediction model,and look forward to the possible directions in the future.

关键词： Solar flare Coronal mass ejection Solar proton event Machine learning Prediction model

Active learning-based metamodeling for hybrid uncertainty quantification of hydro-mechatronic-control systems:A case study of EHA systems

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Chinese Journal of Aeronautics 2024年第12期37卷 12-30页

作者： Muchen WU Hao CHEN Minghao TAI Tangfan XIAHOU Zehua GE Zhenyu LIU Bing CHU zhongrui zhao Yu LIU AVIC Shenyang Aircraft Design and Research Institute Shenyang 110035China School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Center for System Reliability and Safety University of Electronic Science and Technology of ChinaChengdu 611731China

The Electro-Hydrostatic Actuator(EHA)is a typical hydro-mechatronic control *** to the limited accuracy of measurement,inadequate knowledge,and vague judgments,hybrid uncertainties,including aleatory and epistemic uncertainties,inevitably exist in the performance assessment of EHA *** methods ignored the hybrid uncertainties which can hardly obtain a satisfactory result while wasting a lot of time on the experimental *** overcome this drawback,a metamodeling method for hybrid uncertainty propagation of EHA systems is developed via an active learning Gaussian Process(GP)*** proposed method is bifurcated into three pillars:(A)Initializing the GP model and generating the optimum candidate sampling set by an Optimized Max-Minimize Distance(OMMD)algorithm,which aims to maximize the minimum distance between the added samples and original samples,(B)maximizing the learning function and generating new samples by a developed farthest or nearest judgment strategy,while updating the original GP model,and(C)judging the convergence by three uncertainty metrics,i.e.,the area metric,maximum variance metric,and the mean value metric.A numerical example is exemplified to evaluate the effectiveness and efficiency of the proposed ***,the EHA system of aircrafts is examined to show the application of the proposed method for high-dimensional *** effects of the uncertainties in the Proportional-Integral-Differential(PID)of the EHA system are also examined.

关键词： Electro-Hydrostatic Actuator(EHA) Hybrid uncertainty Metamodeling Optimized Max-Minimize Distance(OMMD) Hydro-mechatronic-control systems

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西藏水资源生态足迹评价与动态预测

浙江大学学报（理学版） 2015年第5期42卷 559-566页

作者：赵忠瑞解传奇丹曲方江平西藏大学农牧学院西藏林芝860000

水资源是人类生存之根本,是社会发展之命脉,随着水危机的日益加剧,水资源短缺已成为全球关注的热点问题.使用生态足迹模型评估了2003~2012年西藏自治区的水资源状况,结果表明：西藏水资源生态足迹2003~2008年间由0.015 4上升至0.021 2h... 详细信息

水资源是人类生存之根本,是社会发展之命脉,随着水危机的日益加剧,水资源短缺已成为全球关注的热点问题.使用生态足迹模型评估了2003~2012年西藏自治区的水资源状况,结果表明：西藏水资源生态足迹2003~2008年间由0.015 4上升至0.021 2hm^2·人^-1,2009~2012年逐渐下降;10年平均水资源生态承载力和生态盈余分别为1.217 0和1.198 6hm^2·人^-1,2003~2012年,生态承载力和生态盈余均呈下降趋势.西藏第一产业水资源生态足迹比例高达90%,第二产业最低为1.07%.藏东南地区的水资源生态盈余明显高于藏北地区,其中拉萨与阿里地区最低;2003~2012年各区人均水资源生态盈余均呈下降趋势,林芝、山南、昌都下降较为显著.经模型预测,西藏2013~2017年的生态盈余仍呈下降趋势,西藏的水资源保护及可持续利用工作应尽快提上日程.

关键词：水资源生态足迹生态承载力生态盈余 ARIMA模型

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论石墨烯的制备和在电化学当中的运用

中国资源综合利用 2020年第4期38卷 47-49页

作者：赵仲睿沈阳航空航天大学沈阳110000

随着科技水平的提升,石墨烯技术的发展越来越成熟,近些年,该技术因自身独特的优势如结构特殊、较大的导电性能等,在不同方面都有相应的应用。对于全世界而言,石墨烯的研究也是一个重要的课题。电化学领域应用石墨烯有很大的发展前景。... 详细信息

随着科技水平的提升,石墨烯技术的发展越来越成熟,近些年,该技术因自身独特的优势如结构特殊、较大的导电性能等,在不同方面都有相应的应用。对于全世界而言,石墨烯的研究也是一个重要的课题。电化学领域应用石墨烯有很大的发展前景。本文分析了石墨烯的制备方法及其在电化学中的运用,为相关行业和工作人员提供借鉴。

关键词：石墨烯电化学制备材料

不同温度循环冷却作用后花岗岩巴西劈裂特征及其物理力学特性演化规律研究

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岩石力学与工程学报 2020年第9期39卷 1797-1807页

作者：李春胡耀青张纯旺赵中瑞靳佩桦胡跃飞赵国凯太原理工大学原位改性采矿教育部重点实验室山西太原030024

干热岩地热开发中,井筒钻进及热储层的热交换都涉及高温岩体受不同程度的冷热循环,导致井筒破裂失稳或热储层破裂程度增加,为了揭示其机制,采用岩石力学试验机并结合声发射监测系统,研究不同温度循环作用后花岗岩的纵波波速及巴西劈裂... 详细信息

干热岩地热开发中,井筒钻进及热储层的热交换都涉及高温岩体受不同程度的冷热循环,导致井筒破裂失稳或热储层破裂程度增加,为了揭示其机制,采用岩石力学试验机并结合声发射监测系统,研究不同温度循环作用后花岗岩的纵波波速及巴西劈裂破坏过程。结果表明:(1)随着温度循环次数的不断增加,2种冷却作用下花岗岩所对应的抗拉强度均逐渐降低,遇水冷却循环作用后花岗岩的抗拉强度要低于自然冷却状态下花岗岩的抗拉强度,且花岗岩在高温高循环次数下的劣化程度较为明显,当温度大于500℃时,花岗岩试样的表观颜色逐渐变为土黄色,试样逐渐由脆性向延性转化。(2)根据温度可以将花岗岩的破坏特征分为3个阶段,在低温阶段(100℃~200℃),试样均沿着巴西圆盘中心线发生破裂;中温阶段(300℃~400℃),试样沿着与直径呈一定角度破裂;高温阶段(500℃~700℃),试样破裂模式复杂,较为破碎。(3)低温阶段时的花岗岩随温度循环的变化其纵波波速、强度特征以及变形均变化较小;当试样处于中、高温度阶段时,随循环次数的增加其强度、波速等各项参数衰减幅度逐渐增大。研究结果可为地热开发中井筒破坏失稳及热储层岩体的破裂模式提供理论参考。

关键词：岩石力学巴西劈裂高温花岗岩抗拉强度循环冷却破坏模式

山东省新型冠状病毒肺炎疫情流行趋势初步预测

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重庆师范大学学报（自然科学版） 2020年第2期37卷 101-106页

作者：徐娟年马冉赵中睿程灏青岛理工大学管理工程学院山东青岛266525

【目的】通过建立传染病模型和计算山东省新型冠状病毒肺炎的基本再生数,预测并分析疫情的高峰期和转折点。评价山东省复工后针对新型冠状病毒肺炎疫情采取的相关干预措施的作用。【方法】依据山东省卫生健康委员会公布的2020年1月23日... 详细信息

【目的】通过建立传染病模型和计算山东省新型冠状病毒肺炎的基本再生数,预测并分析疫情的高峰期和转折点。评价山东省复工后针对新型冠状病毒肺炎疫情采取的相关干预措施的作用。【方法】依据山东省卫生健康委员会公布的2020年1月23日至3月15日的疫情数据,利用MATLAB建立SEIR模型,预测疫情高峰期,并计算现阶段新型冠状病毒肺炎基本再生数,基于现有数据通过二次函数拟合和指数平滑法对未来基本再生数的变化趋势加以预测,尝试分析复工后防控手段的有效性。【结果】山东省疫情逐渐趋缓,预测结果显示,山东省疫情于2月23日左右出现高峰,3月26日左右迎来转折点,政府面对复工采取的防疫措施取得了相对显著的效果。【结论】山东省目前处于防疫工作的关键时刻,在转折点到来之前要严格做好防疫措施。

关键词：新型冠状病毒 SEIR模型基本再生数指数平滑法复工

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抗寒与非抗寒植物实生苗根茎结构的差异

东北林业大学学报 2007年第7期35卷 78-79页

作者：肖平朱俊义肖智赵忠蕊通化师范学院通化134002

采用电镜技术系统地研究了抗寒植物辽东桤木、水曲柳与非抗寒植物悬铃木、天女木兰4种植物实生苗根、茎的结构。结果表明:抗寒植物辽东桤木和水曲柳1年生实生苗根部、茎基部、茎顶端的次生生长旺盛,次生结构完整;非抗寒植物悬铃木和天... 详细信息

采用电镜技术系统地研究了抗寒植物辽东桤木、水曲柳与非抗寒植物悬铃木、天女木兰4种植物实生苗根、茎的结构。结果表明:抗寒植物辽东桤木和水曲柳1年生实生苗根部、茎基部、茎顶端的次生生长旺盛,次生结构完整;非抗寒植物悬铃木和天女木兰1年生实生苗的根部及茎基部次生生长较旺盛,次生结构完整,但茎顶端的次生生长极弱,次生结构不完整。

关键词：辽东桤木水曲柳悬铃木天女木兰次生结构抗寒性非抗寒性