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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 539-546页

作者： Wen WANG da-peng xie Hui ZHOU School of Mathematics and Statistics Hefei Normal UniversityHefei 230601China

In this paper,we prove a local Hamilton type gradient estimate for positive solution of the nonlinear parabolic equation ut(x,t)=Δu(x,t)+au(x,t) ln u(x,t)+bu^(α)(x,t),on M×(-∞,∞) with α∈R,where a and b are *** ... 详细信息

关键词： nonlinear parabolic equation gradient estimate Harnack inequality

Variations and future projections of glacial discharge of Urumqi River Headwaters,eastern Tien Shan(1980s-2017)

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Advances in Climate Change Research 2024年第3期15卷 537-546页

作者： Hui ZHANG Fei-Teng WANG Ping ZHOU Yi-da xie State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

To address data scarcity on long-term glacial discharge and inadequacies in simulating and predicting hydrological processes in the Tien Shan,this study analysed the observed discharge at multiple timescales over 1980se2017 and projected changes within a representative glacierized high-mountain region:eastern Tien Shan,Central *** processes were simulated to predict changes under four future scenarios(SSP1,SSP2,SSP3,and SSP5)using a classical hydrological model coupled with a glacier dynamics *** rates at annual,monthly(June,July,August)and daily timescales were obtained from two hydrological gauges:Urumqi Glacier No.1 hydrological station(UGH)and Zongkong station(ZK).Overall,annual and summer discharge increased significantly(p<0.05)at both stations over the study *** intra-annual variations mainly resulted from differences in their recharge *** simulations show that a tipping point in annual discharge at UGH may occur between 2018 and 2024 under the four SSPs *** discharge is predicted to cease earlier at ZK than at *** relates to glacier type and size,suggesting basins with heavily developed small glaciers will reach peak discharge sooner,resulting in an earlier freshwater supply *** findings serve as a reference for research into glacial runoff in Central Asia and provide a decision-making basis for planning local water-resource projects.

关键词： Observed glacial discharge Temporal variations Urumqi River Headwaters Eastern Tien Shan Simulation and projection

AI for science: Predicting infectious diseases

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Journal of Safety Science and Resilience 2024年第2期5卷 130-146页

作者： Alexis Pengfei Zhao Shuangqi Li Zhidong Cao Paul Jen-Hwa Hu Jiaojiao Wang Yue Xiang da xie Xi Lu Institute of Automation Chinese Academy of SciencesUniversity of Chinese Academy of SciencesBejing 100090China Systems Engineering Cornll UniversityIthacaNY 14853USA david Eccles School of Business the University of UtahUtahUSA Collge of Electrical Engineering Sichuan UniversityChina Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering Southeast UniversityNanjing 210096China

The global health landscape has been persistently challenged by the emergence and re-emergence of infectious *** epidemiological models,rooted in the early 2oth century,have provided foundational in-sights into disease ***,the intricate web of modern global interactions and the exponential growth of available data demand more advanced predictive *** is where AI for Science(AI4S)comes into play,offering a transformative approach by integrating artificial intelligence(Al)into infectious disease *** paper elucidates the pivotal role of AI4s in enhancing and,in some instances,superseding tradi-tional epidemiological *** harnessing AI's capabilities,AI4S facilitates real-time monitoring,sophisticated data integration,and predictive modeling with enhanced *** comparative analysis highlights the stark contrast between conventional models and the innovative strategies enabled by *** essence,Al4S represents a paradigm shift in infectious disease *** addresses the limitations of traditional models and paves the way for a more proactive and informed response to future *** we navigate the complexities of global health challenges,Al4S stands as a beacon,signifying the next phase of evolution in disease prediction,characterized by increased accuracy,adaptability,and efficiency.

关键词： AI for science(AI4S) data integration Global healthchallenges Infectious disease prediction Predictive modeling Real-timemonitoring

A social computing method for energy safety

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Journal of Safety Science and Resilience 2024年第1期5卷 64-82页

作者： Pengfei Zhao Shuangqi Li Zhidong Cao Paul Jen-Hwa Hu daniel dajun Zeng da xie Yichen Shen Jiangfeng Li Tianyi Luo Institute of Automation Chinese Academy of SciencesUniversity of Chinese Academy of SciencesBeijing 100090China Systems Engineering Cornell UniversityIthacaNY 14853USA david Eccles School of Business the University of UtahUtahUSA Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China China University of Mining and Technology China

Information and communication technologies enable the transformation of traditional energy systems into cyber-physical energy systems(CPESs),but such systems have also become popular targets of ***,available methods for evaluating the impacts of cyberattacks suffer from limited resilience,efficacy,and practical *** mitigate their potentially disastrous consequences,this study suggests a two-stage,discrepancy-based optimization approach that considers both preparatory actions and response measures,integrating concepts from social *** proposed Kullback-Leibler divergence-based,distributionally robust optimization(KDR)method has a hierarchical,two-stage objective function that incorporates the operating costs of both system infrastructures(e.g.,energy resources,reserve capacity)and real-time response measures(e.g.,load shedding,demand-side management,electric vehicle charging station management).By incorporating social computing principles,the optimization framework can also capture the social behavior and interactions of energy consumers in response to *** preparatory stage entails day-ahead operational decisions,leveraging insights from social computing to model and predict the behaviors of individuals and communities affected by potential *** mitigation stage generates responses designed to contain the consequences of the attack by directing and optimizing energy use from the demand side,taking into account the social context and preferences of energy consumers,to ensure resilient,economically efficient CPES *** method can determine optimal schemes in both stages,accounting for the social dimensions of the *** original disaster mitigation model uses an abstract formulation to develop a risk-neutral model that characterizes cyberattacks through KDR,incorporating social computing techniques to enhance the understanding and response to cyber *** approach can mitigate the impacts more

关键词： Cyberattacks Cyber-physical energy systems Distributionally robust optimization False data injections Two-stage modeling Social computing

并网型直流微电网的非线性降阶建模及其估计吸引域的优化计算

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中国电机工程学报 2024年第2期44卷 517-534,I0007页

作者：孙圣欣汤晨煜解大古丽扎提·海拉提顾承红张延迟王西田电力传输与功率变换控制教育部重点实验室(上海交通大学) 上海市闵行区200240 上海第二工业大学上海市浦东新区201209 巴斯大学英国巴斯BA27AY 上海电机学院上海市闵行区200240

面对“双高”电力系统的高维度、高随机性和强非线性,现有的建模和稳定性分析方法受限于维度、难以求解且准确度低。针对此问题,该文提出一个面向“双高”电力系统,包含非线性降阶建模和估计吸引域优化计算的稳定性分析框架。首先,考虑... 详细信息

面对“双高”电力系统的高维度、高随机性和强非线性,现有的建模和稳定性分析方法受限于维度、难以求解且准确度低。针对此问题,该文提出一个面向“双高”电力系统,包含非线性降阶建模和估计吸引域优化计算的稳定性分析框架。首先,考虑分布式光伏和恒功率负载的地理环境因素,应用Pioncáre规范理论,将并网型直流微电网的二次状态偏差模型依次进行分块降维、解耦和降阶变换,建立一阶二次微分方程形式的非线性降阶模型。然后,基于李雅普诺夫稳定判据,结合构造含辅助变量的最优化模型思想,并利用克罗内克积性质,提出估计吸引域的优化计算方法,构建优化的估计吸引域(optimalestimatedregionofattraction,OEROA)。最后,以分布式光伏云层遮蔽和恒功率负载扰动下的微电网系统作为算例,与基于LaSalle定理的李雅普诺夫法、Takagi-Sugeno(T-S)模糊模型法对比,验证所提方法构建的估计吸引域具有更低的保守性,以及所提分析框架的有效性。

关键词：并网型直流微电网非线性降阶建模优化的估计吸引域二次状态偏差模型分块解耦

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船用柴油机气缸套内孔平台网纹珩磨加工工艺

柴油机 2024年第3期46卷 56-60页

作者：程世昌林琳钱进谢达王洪兵上海船用柴油机研究所上海201108 船舶与海洋工程特种装备和动力系统国家工程研究中心上海201108 扬州五亭桥缸套有限公司扬州225100

针对某船用柴油机气缸套内孔平台网纹珩磨加工工艺,对气缸套加工时的网纹形成机理进行分析,制定平台网纹珩磨工艺路线,并确定相应的珩磨工艺参数和加工设备,以保证平台网纹达到要求。柴油机试车结果证明采用该平台网纹珩磨加工工艺可满... 详细信息

针对某船用柴油机气缸套内孔平台网纹珩磨加工工艺,对气缸套加工时的网纹形成机理进行分析,制定平台网纹珩磨工艺路线,并确定相应的珩磨工艺参数和加工设备,以保证平台网纹达到要求。柴油机试车结果证明采用该平台网纹珩磨加工工艺可满足缸套网纹加工高精度要求。

关键词：船用柴油机气缸套珩磨平台网纹

Lipoprotein(a)variability is associated with mean follow-up Creactive protein in patients with coronary artery disease following percutaneous coronary intervention

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World Journal of Clinical Cases 2022年第35期10卷 12909-12919页

作者： Si-Si Zhang Wen-Yi Hu Yi-Jing Li Juan Yu Shang Sang Zakareya M Alsalman da-Qi xie Department of Cardiology Ningbo Ninth HospitalNingbo 315300Zhejiang ProvinceChina

BACKGROUND Increased lipoprotein(a)[lp(a)]has proinflammatory effects,which increase the risk of coronary artery ***,the association between lp(a)variability and follow-up C-reactive protein(CRP)level in patients undergoing percutaneous coronary intervention(PCI)has not been *** To explore the association between lp(a)variability and mean CRP levels within the 1st year *** Results of lp(a)and CRP measurements from at least three follow-up visits of patients who had received PCI were retrospectively *** deviation(SD),coefficient of variation(CV),and variability independent of the mean(VIM)are presented for the variability for lp(a)and linear regression analysis was conducted to correlate lp(a)variability and mean follow-up CRP *** relationship of lp(a)variability and inflammation status was analyzed by restricted cubic spline ***,exploratory analysis was performed to test the consistency of results in different *** A total of 2712 patients were *** with higher variability of lp(a)had a higher level of mean follow-up CRP(P<0.001).lp(a)variability was positively correlated with the mean follow-up CRP(SD:β=0.023,P<0.001;CV:β=0.929,P<0.001;VIM:β=1.648,P<0.001)by multivariable linear regression *** analysis showed that the positive association remained consistent in most *** Lp(a)variability correlated with mean follow-up CRP level and high variability could be considered an independent risk factor for increased post-PCI CRP level.

关键词： Lipoprotein(a) Variability C-reactive protein Coronary artery disease Percutaneous coronary intervention

碳排放约束下广西城市建设用地利用效率特征分析

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智能建筑与智慧城市 2024年第1期 6-9页

作者：唐惠婷李庆覃雪华谢达么徐冰冰王永卿南宁师范大学自然资源与测绘学院

土地利用/覆被变化是影响碳排放、碳吸收量变化的主要原因。本文通过碳排放系数间接估算法、HicksMoorsteen生产率指数分析广西2011年-2020年城镇建设用地利用效率动态变化,结果发现:(1)广西建设用地碳排放总量的变化趋势可分为“先升... 详细信息

土地利用/覆被变化是影响碳排放、碳吸收量变化的主要原因。本文通过碳排放系数间接估算法、HicksMoorsteen生产率指数分析广西2011年-2020年城镇建设用地利用效率动态变化,结果发现:(1)广西建设用地碳排放总量的变化趋势可分为“先升后降再升”三个阶段,地均碳排放总量整体呈“先降后升”的趋势,万元GDP碳排放量的变化呈平稳下降趋势;(2)广西全区HM指数呈现年平均4.87%的上升趋势,受综合利用效率(Δ_(E))和技术进步(Δ_(tech))共同驱动,各市城镇建设用地利用效率都出现微小波动的上升趋势,呈现出区域的非均衡性。广西应综合考虑各市城镇建设用地利用效率存在的问题,因地制宜实施产业转型、能源结构优化以及节能环保等政策。

关键词：建设用地碳排放土地利用效率 Hicks-Moorsteen指数广西

Mass extinctions, their causes and consequences: an interview with Douglas *** and Shuzhong Shen

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National Science Review 2024年第1期11卷 66-70页

作者： Shucheng xie State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public *** spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing University, China.

关键词： Stratigraphy

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神灯

十月 2023年第5期 167-179页

作者：大解不详

长老听见外面传来一声咳嗽,听出是铁匠的声音,并且知道铁匠已经走进了院子,就说,铁匠进来吧。随后他就取下糊墙纸上别着的针,用针尖把油灯的火苗往上挑了挑,油灯的亮度就增大了,屋子里顿时亮堂了不少。长老嘟曦着说,这么晚了,铁匠来一... 详细信息

长老听见外面传来一声咳嗽,听出是铁匠的声音,并且知道铁匠已经走进了院子,就说,铁匠进来吧。随后他就取下糊墙纸上别着的针,用针尖把油灯的火苗往上挑了挑,油灯的亮度就增大了,屋子里顿时亮堂了不少。长老嘟曦着说,这么晚了,铁匠来一定是有事。就在长老自言自语说话的时候,铁匠走进了长老的屋里。长老也没说客套话,铁匠进屋后坐在了炕沿上,也不看长老,说灯芯挑这么高,太费油了,还是小一点吧,于是他从墙上取下针,走过去把灯芯棉往里扎了一下,灯火一下子短了很多,火苗变成了豆粒大小。铁匠扎完灯芯后又把针别在了墙上。长老家的针放在哪里,他是熟悉的,这根针是他亲自打制的,多年前他送给长老的那天,当时就别在了糊墙纸上,这么多年来就一直在墙上别着,从来没有换过地方。

关键词：灯芯自言自语铁匠油灯灯火长老