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具有反馈控制的捕食链模型的永久持续生存

西北大学学报（自然科学版） 2011年第5期41卷 775-780页

作者：王爱丽宝鸡文理学院数学系陕西宝鸡721013

目的讨论了一类具有多时滞和αi类功能性反应函数的三种群捕食链模型。方法利用比较原理和构造持久生存函数的方法。结果得到了模型永久持续生存的充分条件,并且给出了其永久持续生存域。建立具体模型说明所得结果的可行性。结论模型中... 详细信息

目的讨论了一类具有多时滞和αi类功能性反应函数的三种群捕食链模型。方法利用比较原理和构造持久生存函数的方法。结果得到了模型永久持续生存的充分条件,并且给出了其永久持续生存域。建立具体模型说明所得结果的可行性。结论模型中三个种群在适当的条件下,是可以持久生存的。

关键词：永久持续生存反馈控制捕食链模型

具有加强诊断措施的Filippov HIV/aiDS传染病模型

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工程数学学报 2020年第5期37卷 615-630页

作者：王爱丽宝鸡文理学院数学与信息科学学院宝鸡721013

本文建立Filippov HIV/aiDS传染病模型,用以刻画如下诊断措施:一旦已诊断HIV感染者数量超过某一水平,便启用加强的诊断措施;否则实施普通的诊断措施.应用等效控制法讨论了所建立模型的滑动模式区域和滑动动力学,在此基础上通过定性分析... 详细信息

本文建立Filippov HIV/aiDS传染病模型,用以刻画如下诊断措施:一旦已诊断HIV感染者数量超过某一水平,便启用加强的诊断措施;否则实施普通的诊断措施.应用等效控制法讨论了所建立模型的滑动模式区域和滑动动力学,在此基础上通过定性分析讨论了模型的全局动力学.数值结果表明,当阈值水平足够高或足够低时,HIV感染者数量最终稳定在一个相对较高或较低的水平;若选取一个恰当的阈值,HIV感染者数量最终会围绕该阈值波动.这说明阈值水平的选取对控制HIV至关重要,据此可确定是否有必要实施加强的诊断措施.

关键词： Filippov模型 HIV感染伪平衡态穿越极限环干预

具有脉冲控制和病毒感染的害虫治理模型的分支分析

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山东大学学报（理学版） 2020年第7期55卷 1-8页

作者：王爱丽宝鸡文理学院数学与信息科学学院陕西宝鸡721013

讨论了一类具有状态依赖反馈控制和病毒感染的害虫模型边界周期解的存在性,得到了边界周期解全局稳定的条件。给出了模型发生跨临界分岔的条件,并通过数值方法分析了杀虫剂功效和单次投放感染害虫比例对实施控制措施的频率影响。研究结... 详细信息

讨论了一类具有状态依赖反馈控制和病毒感染的害虫模型边界周期解的存在性,得到了边界周期解全局稳定的条件。给出了模型发生跨临界分岔的条件,并通过数值方法分析了杀虫剂功效和单次投放感染害虫比例对实施控制措施的频率影响。研究结果说明,状态依赖控制措施在一定条件下可转化为周期控制措施;执行控制措施的频率随着单次投放感染害虫比例增大而减小,但是随着杀虫剂功效增大,该频率可能减小也可能增大。

关键词：害虫控制状态依赖反馈控制半动力系统周期解跨临界分支

Multi-Granularity Neighborhood Fuzzy Rough Set Model on Two Universes

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Journal of Intelligent Learning Systems and Applications 2024年第2期16卷 91-106页

作者： Ju wang Xinghu ai li Fu School of Mathematics and Statistics Qinghai Nationalities University Xining China Xining Big Date Center Xining China

The two universes multi-granularity fuzzy rough set model is an effective tool for handling uncertainty problems between two domains with the help of binary fuzzy relations. This article applies the idea of neighborhood rough sets to two universes multi-granularity fuzzy rough sets, and discusses the two-universes multi-granularity neighborhood fuzzy rough set model. Firstly, the upper and lower approximation operators are defined in the two universes multi-granularity neighborhood fuzzy rough set model. Secondly, the properties of the upper and lower approximation operators are discussed. Finally, the properties of the two universes multi-granularity neighborhood fuzzy rough set model are verified through case studies.

关键词： Fuzzy Set Two Universes Multi-Granularity Rough Set Multi-Granularity Neighborhood Fuzzy Rough Set

Resilience and response:Unveiling the impacts of extreme droughts on forests through integrated dendrochronological and remote sensing analyses

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Forest Ecosystems 2024年第4期11卷 491-501页

作者： Han Shi Xi Peng Yong-Jiao Zhou ai-Ying wang Xue-Kai Sun Na li Quan-Sheng Bao Gude Buri Guang-You Hao CAS Key Laboratory of Forest Ecology and Silviculture Institute of Applied EcologyChinese Academy of SciencesShenyang110016China Daqinggou Ecological Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang110016China University of Chinese Academy of Sciences Beijing100049China School of life Science and Engineering Shenyang UniversityShenyang110044China Wudantala Forestry Forestry and Grassland Administration of Horqin Northeast CountyTongliao028100China

Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate ***,considerable uncertainty remains regarding the patterns in species-specific responses to extreme ***,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast *** assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation *** results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar *** RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy *** contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial ***,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth *** study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and *** study improves our understanding of forest responses to extreme drought and highlights species di

关键词： Introduced tree species Native tree species NDVI Severe drought Tree-ring width

Volume-averaged modeling of multiphase solidification with equiaxed crystal sedimentation in a steel ingot

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China Foundry 2024年第3期21卷 229-238页

作者： Xiao-lei Zhu Shuang Cao Rui Guan Ji Yang Zhe Ning Xin-gang ai Sheng-li li Xin-cheng Miao The key Laboratory of Material Forming and Structure Property Control Anshan 114051LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114009LiaoningChina School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina

Macrosegregation is a critical factor that limits the mechanical properties of *** impact of equiaxed crystal sedimentation on macrosegregation has been extensively studied,as it plays a significant role in determining the distribution of alloying elements and impurities within a *** improve macrosegregation in steel connecting shafts,a multiphase solidification model that couples melt flow,heat transfer,microstructure evolution,and solute transport was established based on the volume-averaged Eulerian-Eulerian *** this model,the effects of liquid phase,equiaxed crystals,columnar dendrites,and columnar-to-equiaxed transition(CET)during solidification and evolution of microstructure can be considered *** sedimentation of equiaxed crystals contributes to negative macrosegregation,where regions between columnar dendrites and equiaxed crystals undergo significant A-type positive macrosegregation due to the ***,noticeable positive macrosegregation occurs in the area of final solidification in the *** improvement in macrosegregation is beneficial for enhancing the mechanical properties of connecting *** mitigate the thermal convection of molten steel resulting from excessive superheating,reducing the superheating during casting without employing external fields or altering the design of the ingot mold is indeed an effective approach to control macrosegregation.

关键词： ingot casting multiphase solidification model equiaxed crystal sedimentation microstructure macrosegregation

Health benefits from the rapid reduction in ambient exposure to air pollutants after China's clean air actions:progress in efficacy and geographic equality

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National Science Review 2024年第2期11卷 103-113页

作者： Tao Xue Ruohan wang Meng wang Yanying wang Dan Tong Xia Meng Conghong Huang Siqi ai Fangzhou li Jingyuan Cao Mingkun Tong Xueqiu Ni Hengyi liu Jianyu Deng Hong Lu Wei Wan Jicheng Gong Shiqiu Zhang Tong Zhu Institute of Reproductive and Child Health National Health Commission Key Laboratory of Reproductive Health/Department of Epidemiology and Biostatistics Ministry of Education Key Laboratory of Epidemiology of Major Diseases(PKU) School of Public Health Peking University Health Science Centre State Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management and Center for Environment and Health Peking University Advanced Institute of Information Technology Peking University Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at Buffalo State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University Department of Earth System Science Tsinghua University School of Public Health Key Laboratory of Public Health Safety of the Ministry of Education and Key Laboratory of Health Technology Assessment of the Ministry of HealthFudan University College of Land Management Nanjing Agricultural University National&Local Joint Engineering Research Center for Rural Land Resources Use and Consolidation Clean air Asia

Clean air actions （CAAs） in China have been linked to considerable benefits in public ***,whether the beneficial effects of CAAs are equally distributed geographically is *** high-resolution maps of the distributions of major air pollutants (fine particulate matter[PM2.5]and ozone[O3]) and population,we aimed to track spatiotemporal changes in health impacts from,and geographic inequality embedded in,the reduced exposures to PM2.5and O3from 2013 to *** used a method established by the Global Burden of Diseases *** analyzing the changes in loss of life expectancy（LLE） attributable to PM2.5and O3,we calculated the gain of life expectancy （GLE） to quantify the health benefits of the air-quality ***,we assessed the geographic inequality embedded in the GLE using the Gini index （GI）.Based on risk assessments of PM2.5and O3,during the first stage of CAAs（2013 to 2017）,the mean GLE was 1.87 *** of the sum of the GLE was disproportionally distributed in about one quarter of the population exposed （GI 0.44）.During the second stage of CAAs（2017 to 2020）,the mean GLE increased to 3.94 months and geographic inequality decreased （GI 0.18）.According to our assessments,CAAs were enhanced,from the first to second stages,in terms of not only preventing premature mortality but also ameliorating health *** enhancements were related to increased sensitivity to the health effects of air pollution and synergic control of PM2.5and *** findings will contribute to optimizing future CAAs.

关键词： clean air action public health inequality fine particulate matter ozone

Understanding Human and Machine Interaction from Decision Perspective: An Empirical Study Based on the Game of Go

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Journal of Systems Science & Complexity 2024年第2期37卷 647-667页

作者： ZHAO Ping li Xuerong wang Shouyang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China

The authors aim to interpret human and ai interactions from the decision *** authors decompose the interaction analysis into the following main components in the context of interactions:Individual behavior patterns,interaction relationships,and comprehensive *** authors interpret intertemporal decisions from a physical perspective and employ cross-discipline concepts and methodologies to extract the behavior characteristics of players in the empirical case *** the individual behavior patterns,the authors find that human players prefer short-term periods to ai in *** interaction relationship analysis reveals a dynamic relationship between possible short-term co-movement and nearly counter-movement in the long *** authors apply principal component analysis to descriptive indicators and discover a regular decision *** main behavior pattern of players in the game of Go is switching between careful and daring *** differences in the decision hierarchies imply a discrepancy of patience between humans and ai.

关键词： Coherence analysis decision hierarchy machine behaviour multitaper spectral analysis

Electrical uniformity analyses on 12-inch Si-based Hf0.5Zr0.5O2 ferroelectric capacitor devices by atomic layer deposition

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Progress in Natural Science:Materials International 2024年第3期34卷 598-605页

作者： Wen-Juan Ding Yu liu Zhi-Qiang Xiao li Gao Yu-Chen li lin Zhu Xiang li Wei-Min li Shuang Chen ai-Dong li National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced MicrostructuresNanjing University Jiangsu Leadmicro Nano-Technology Co. Ltd. Semiconductor Manufacturing North China Corp. Kuang Yaming Honors School Nanjing University

The study on the uniformity of electrical performance of large wafer-scale Hf0.5Zr0.5O2（HZO） ferroelectric capacitors is still lacking yet now. In this work, TiN/HZO/TiN metal-ferroelectric-metal（MFM） devices on 12-inch silicon wafers have been fabricated by thermal atomic layer deposition. The correlation of thickness uniformity with device-to-device variation of electrical properties and yield of the 12-inch MFM system was investigated. It was found that the uniformity of ferroelectric properties is closely related to the variation of HZO thickness of the MFM system, the concentration of oxygen vacancies in the micro-region of the HZO film, and the ferroelectric phase micro-distribution on 12-inch Si wafer. This work provides some important information for the performance optimization of HfO2-based ferroelectric random access memories.

关键词： 12-Inch Si wafer Atomic layer deposition Electrical uniformity Ferroelectric random access memory Hf0.5Zr0.5O2 ferroelectric thin film