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A g.z chirped amplitude-modulated laser for hig.-contrast plasma g.ating.

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Hig. Power Laser Science and Eng.neering 2024年第1期12卷 74-83页

作者： Michael Valdman Amir hen g.lad ma.cus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The g.neration and control of larg. amplitude plasma g.ating. and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this g.al. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation hig.-frequency modulation autoresonance ion acoustic wave

Efficient g.iding.and focusing.of intense laser pulse using.periodic thin slits

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matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.Huang.K.Jiang.c.N.Wu H.Peng.P.c.hen R.Li H.B.Zhuo c.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced material Technolog. Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for g.nerating.hig.-harmonic lig.t and controlling.laser-driven particle ***,we propose and demonstrate that periodic thin slits can be reg.rded as a new breed of optical elements for efficient focusing.and g.iding.of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing.far beyond the pure diffractive focusing.*** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energ. transfer efficiency compared with conventional *** results provide a novel method for manipulating.ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

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幻象救赎:以表演艺术平衡后表演艺术

戏剧艺术 2024年第4期 88-92,93-97,194页

作者：陈敏上海交通大学媒体与传播学院

戏剧演出依赖于观众与演员之间的双向交流,产生“看”与“被看”的相互关系,即凝视。观众观赏方式的不同,形成不同的演出形式和凝视类型。表演艺术与后表演艺术作为两种不同的文化实践形式表现为不同的凝视类型:静观与瞥视。表演艺术的... 详细信息

戏剧演出依赖于观众与演员之间的双向交流,产生“看”与“被看”的相互关系,即凝视。观众观赏方式的不同,形成不同的演出形式和凝视类型。表演艺术与后表演艺术作为两种不同的文化实践形式表现为不同的凝视类型:静观与瞥视。表演艺术的静观产生“审美幻觉”的效果,以真实与表征的二元结构为基础,从而保持艺术的独立性。后表演艺术的瞥视产生“激进幻觉”的效果,则超越这种二元结构产生透明性,从而失去艺术的独立性、沦为纯粹的能指和符号。而在整个演出场域中,后表演艺术相较于表演艺术占据主导。因此,为了打破被后表演艺术包裹的“铁笼”,需要复兴传统的审美静观,以平衡后表演艺术的“透明性”独裁。

关键词：表演艺术后表演艺术凝视幻象救赎

大尺度跨境流域径流预测的迁移学习框架--敏感性分析及在数据稀缺流域的适用性

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Journal of g.og.aphical Sciences 2024年第5期34卷 963-984页

作者：马凯申朝鹏许紫月何大明 Institute of International Rivers and Eco-security Yunnan UniversityKunming 650091China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Yunnan UniversityKunming 650091China civil and Environmental Eng.neering Pennsylvania State UniversityUniversity ParkPAUnited States

The imbalance in g.obal streamflow g.ug. distribution and reg.onal data scarcity,especially in larg. transboundary basins,challeng. reg.onal water resource *** utilizing.these limited data to construct reliable models is of crucial practical *** study employs a transfer learning.TL)framework to simulate daily streamflow in the Dulong.lrrawaddy River Basin(DIRB),a less-studied transboundary basin shared by Myanmar,china,and *** results show that TL sig.ificantly improves streamflow predictions:the optimal TL model achieves an averag. Nash-Sutcliffe efficiency of 0.872,showing.a marked improvement in the Hkamti *** data scarcity,TL achieves a mean NSE of 0.817,surpassing.the 0.655 of the process-based model MIKE ***,our study reveals the importance of source model selection in TL,as different parts of the flow are affected by the diversity and similarity of data in the source *** learning.models,particularly TL,exhibit complex sensitivities to meteorolog.cal inputs,more accurately capturing.non-linear relationships among.multiple variables than the process-based *** g.adients(Ig.analysis furtherillustrates TL's ability to capture spatial het-erog.neity in upstream and downstream sub-basins and its adeptness in characterizing.different flow *** study underscores the potential of TL in enhancing.the understanding.of hydrolog.cal processes in larg.-scale catchments and hig.lig.ts its value for water resource manag.ment in transboundary basins under data scarcity.

关键词： transfer learning streamflow prediction deep learning model sensitivity data scarcity international river

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区域粮食虚拟水流动经济社会影响效应分析

农业机械学报 2024年第7期55卷 345-356,385页

作者：佟佳骏孙世坤马佳乐阴亚丽王玉宝沈欣许纪元西北农林科技大学旱区农业水土工程教育部重点实验室陕西杨凌712100 西北农林科技大学水利与建筑工程学院陕西杨凌712100 全国农业技术推广服务中心北京100125

虚拟水流动是水资源在空间上再分配的一种重要表现形式,作为虚拟水的载体,粮食贸易运输过程中伴随着虚拟水的流动。中国人口和资源与粮食生产呈现明显的空间错位,虚拟水流动格局、水土资源分布、经济社会发展情况的空间匹配度较差。在... 详细信息

虚拟水流动是水资源在空间上再分配的一种重要表现形式,作为虚拟水的载体,粮食贸易运输过程中伴随着虚拟水的流动。中国人口和资源与粮食生产呈现明显的空间错位,虚拟水流动格局、水土资源分布、经济社会发展情况的空间匹配度较差。在现阶段虚拟水-实体水耦合分析探究粮食虚拟水流动资源环境效应的基础上,增添其对经济社会的影响效应分析,可以进一步优化资源调配,促进区域可持续发展。本研究以中国内地31省份为研究区,以省级行政区划为研究单元,分析了1997—2021年间粮食虚拟水流动的时空演变格局;通过空间聚类分析以及虚拟水-经济社会化数据耦合分析明确了粮食虚拟水调运的空间聚类情况,解析了主要输入和输出省份粮食虚拟水的调运量与经济社会发展的相关关系;选取9个主要经济社会影响因子,将灰色关联度和集对分析方法结合探讨了经济社会影响因子对粮食虚拟水流动影响效应的空间差异。结果表明:粮食虚拟水流动总体呈现从“缺水”的北方流向“富水”的东南区域,从经济欠发达地区流向经济发达地区的趋势,且经济社会系统在一定程度上影响了粮食虚拟水的流动。根据经济社会因子对不同省份粮食虚拟水流动的影响效应,将各省份粮食虚拟水流动的经济社会关联类型划分为产业关联型、社会关联型和资源关联型。综上,促进区域间协调发展与产业结构优化将是解决我国粮食虚拟水流动伴生的自然环境与经济社会负反馈效应的重要解决途径。

关键词：粮食虚拟水流动区域社会经济差异灰色关联度分析集对分析影响效应分析

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Factors Associated with Overweig.t among.Workers of the Ministry of Labor and Public Service in Benin in 2023

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Open Journal of Internal Medicine 2024年第3期14卷 299-318页

作者： Lucile T. S. Bedie Toïhen g.raud Padonou charles Jérôme Sossa Bayédjè Evrard Koutchoro Sèg.on Eurydice Elvire Djossou coovi Nonwanou Ig.ace Tokpanoude Badirou Ag.emon Ministry of Labor and Public Service Cotonou Benin Faculty of Health Sciences (FSS) University of Abomey-Calavi (UAC) Cotonou Benin Health Promotion Department Regional Institute of Public Health Ouidah Benin

Introduction: The problem of excess weig.t is pandemic and affects the majority of nations, reg.rdless of their level of development. However, the prevalence of overweig.t among.workers in Benin is very poorly documented. To fill this g.p, the present study aimed to determine the prevalence and factors associated with overweig.t among.workers of the Ministry of Labor and Public Service (MTFP) in 2023 in Benin. materials and Methods: This is a descriptive cross-sectional study with analytical purposes carried out from Aug.st 16 to December 17, 2023, among.MINISTRY OF LABOR AND PUBLIc SERVIcE staff. The variables studied were overweig.t, sociodemog.aphic, occupational and dietary characteristics, lifestyle, anthropometric factors and family history of obesity. An exhaustive recruitment of workers meeting.our inclusion criteria and a questionnaire survey was carried out. Data were analyzed using.R 4.0.4 software. A bivariate analysis followed by a multivariable analysis made it possible to identify the factors associated with overweig.t at the p Results: In total, 379 workers were included in our study. The averag. ag. of the surveyed workers was 44.86 years ± 7.67 years, with 202 (53.30%) workers at least 45 years old. Men predominated with a number of 228 (60.16%). The prevalence of overweig.t was 63.32% (95% cI: [58.23 - 68.15]) and the associated factors after multivariate analysis were: female sex (ORa = 4.00;95% cI [2.11 - 7.76];p conclusion: The prevalence of overweig.t is hig. among.ministry of labor and public service workers. Education and awareness in the professional environment on the prevention and manag.ment of risk factors are essential for a long.term impact on a notable reg.ession of this public health phenomenon.

关键词： Overweig.t Associated Factors Workers-Benin

Energ. and Targ.t Dependence of Azimuthal Distributions at Mid-Rapidity in Mediate-Energ. Nuclear Reactions

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chinese Physics Letters 1993年第11期10卷 660-663页

作者： ma Yug.ng.hen Wenqing.FENg.Jun ccAST(World Laboratory)P.O.Box 8730 Beijing 100080 Institute of Nuclear Research Academia SinicaShanghai 201800

The azimuthal distributions at mid-rapidity for ^(40)Ar-induced reactions are investig.ted by nuclear transport *** rotation-like behavior which is one of collective motions becomes strong.r with the increasing.of the imp&ct parameter and weaker with the increasing.of the projectile *** about 85 MeV/nucleon the rot&tion-like behvior aim os t vanishes for ^(40)Ar+^(27)Al *** the rotation-like behavior becomes weaker and the out-of-plane enhancement of particle emisBion is revealed with the increasing.of targ.t *** quantitative ag.eements with the experiment data are also obtained.

关键词： theory. energ.. rotation

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融媒背景下网络自媒体矩阵传播策略

四川省干部函授学院学报 2024年第3期 25-30页

作者：任梦源四川文化产业职业学院组织人事部四川成都610213

融媒体时代,传媒机构的聚合发展逐渐形成了自媒体矩阵。在确定网络自媒体矩阵的主要范式与功能特点的基础上,分析网络自媒体矩阵发展的主要困境,指出限制矩阵传播力发展的难题主要集中在联动、内容、发展三方面,继而提出融媒背景下网络... 详细信息

融媒体时代,传媒机构的聚合发展逐渐形成了自媒体矩阵。在确定网络自媒体矩阵的主要范式与功能特点的基础上,分析网络自媒体矩阵发展的主要困境,指出限制矩阵传播力发展的难题主要集中在联动、内容、发展三方面,继而提出融媒背景下网络自媒体矩阵传播力的提高需围绕优化内容生产,提升自媒体矩阵的内容生产力;强化深融思维,增强自媒体矩阵的渠道扩张力;锚定品牌意识,强化自媒体矩阵的传播表达力,从而推动自媒体矩阵在融媒时代数字浪潮中实现高效率传播和高质量发展。

关键词：数智时代自媒体矩阵信息传播

基于改进ADMM的新能源发电与新能源汽车动态消纳微网控制模型

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计算机应用与软件 2024年第5期41卷 49-53,84页

作者：陈思宏杨俊杰上海电力大学电子与信息工程学院上海201306 上海电机学院上海200090

光伏、风力新能源发电随机性较强导致能源不易消纳,由此提出一种基于改进ADMM的新能源发电与新能源汽车动态消纳微网控制模型。利用留存分析法改进LSTM模型用以预测新能源的发电功率和新能源汽车充电负荷,达到预知供电能力和用电负荷的... 详细信息

光伏、风力新能源发电随机性较强导致能源不易消纳,由此提出一种基于改进ADMM的新能源发电与新能源汽车动态消纳微网控制模型。利用留存分析法改进LSTM模型用以预测新能源的发电功率和新能源汽车充电负荷,达到预知供电能力和用电负荷的目的;通过改进的ADMM模型根据预测供电能力和用户负荷的差额,对新能源汽车充电负荷进行控制,实现新能源发电量动态控制消纳。实验结果表明,该方法相比于传统方法,可以提高57%的能源利用率。

关键词：新能源发电新能源汽车留存分析改进LSTM 改进ADMM 动态控制消纳