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Control.Pol.cy l.arning Design for Vehicl. Urban Positioning via BeiDou Navigation

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Journal.of Systems Science & Compl.xity 2024年第1期37卷 114-135页

作者： QIN Yahang ZHANG Chengye CHEN Ci xie Shengl. l.WIS Frank l School.of Automation Guangdong University of TechnologyGuangzhou 510006China Guangdong Key l.boratory of IoT Information Technol.gy Guangzhou 510006China. Center for Intel.igent Batch Manufacturing Based on IoT Technol.gy Key l.boratory of Intel.igent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Guangdong-HongKong-Macao Joint l.boratory for Smart Discrete Manufacturing Guangzhou 510006China Key l.boratory of Intel.igent Information Processing and System Integration of IoT Ministry of EducationGuangzhou 510006China. UTA Research Institute The University of Texas at ArlingtonFort WorthTX 76019USA

This paper presents a l.arning-based control.pol.cy design for point-to-point vehicl. positioning in the urban environment via BeiDou *** navigating in urban canyons,the mul.ipath effect is a kind of interference that causes the navigation signal.to drift and thus imposes severe impacts on vehicl. l.cal.zation due to the refl.ction and diffraction of the BeiDou ***,the authors formul.ted the navigation control.system with unknown vehicl. dynamics into an optimal.control.seeking probl.m through a l.near discrete-time system,and the point-to-point l.cal.zation control.is model.d and handl.d by l.veraging off-pol.cy reinforcement l.arning for feedback *** proposed l.arning-based design guarantees optimal.ty with prescribed performance and al.o stabil.zes the cl.sed-l.op navigation system,without the ful. knowl.dge of the vehicl. *** is seen that the proposed method can withstand the impact of the mul.ipath effect whil. satisfying the prescribed convergence rate.A case study demonstrates that the proposed al.orithms effectivel. drive the vehicl. to a desired setpoint under the mul.ipath effect introduced by actual.experiments of BeiDou navigation in the urban environment.

关键词： BeiDou navigation mul.ipath effect prescribed convergence rate reinforcement l.arning urban l.cal.zation.

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电子文件与电子证据领域中的真实性概念分析

浙江档案 2019年第1期 13-17页

作者：谢丽范冠艳中国人民大学信息资源管理学院

本研究以我国法律条款对真实性的定义和要求为依托,分析其与国内文件档案界对真实性一词理解的异同,同时与加拿大做相关的比较。研究发现,我国文件档案界对真实性的使用既和我国法律中的证据条款不同,又和加拿大证据法中的"真实性(Authe... 详细信息

本研究以我国法律条款对真实性的定义和要求为依托,分析其与国内文件档案界对真实性一词理解的异同,同时与加拿大做相关的比较。研究发现,我国文件档案界对真实性的使用既和我国法律中的证据条款不同,又和加拿大证据法中的"真实性(Authenticity)"一词相异。研究发现,概念严谨性的不足和体系的缺乏是我国法律界和文件档案界都面临的一个问题,现有的证据条款对真实性判定的要求严格但对判定的具体途径却三缄其口。研究认为,文件档案界应在完善自身概念体系的基础上加入电子证据真实性概念及其判定途径的讨论,以自身学科的专业知识和技能促进电子证据立法的系统性和实施的可操作性。

关键词：电子文件电子档案电子证据证据法加拿大

Stabil.ty and performance anal.sis of the compressed Kal.an fil.er al.orithm for sparse stochastic systems

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Science China(Technol.gical.Sciences) 2024年第2期67卷 380-394页

作者： l. RongJiang GAN Die xie SiYu l.JinHu Key l.boratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School.of Mathematical.Sciences University of Chinese Academy of SciencesBeijing 100049China Zhongguancun l.boratory Beijing 100049China School.of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School.of Automation Science and El.ctrical.Engineering Beihang UniversityBeijing 100191China

This paper considers the probl.m of estimating unknown sparse time-varying signal. for stochastic dynamic *** deal.with the chal.enges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kal.an fil.er(KF)*** al.orithm first compresses the original.high-dimensional.sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed l.w-dimensional.***,the original.high-dimensional.sparse signal. can be wel. recovered by a reconstruction *** ensure stabil.ty and establ.sh upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal.and therefore suitabl. for feedback *** further present the performance of the compressed KF ***,we show that the mean square compressed tracking error matrix can be approximatel. cal.ul.ted by a l.near deterministic difference matrix equation,which can be readil. eval.ated,anal.zed,and ***,a numerical.exampl. demonstrates that our al.orithm outperforms the standard uncompressed KF al.orithm and other compressed al.orithms for estimating high-dimensional.sparse signal..

关键词： sparse signal compressed sensing Kal.an fil.er al.orithm compressed excitation condition stochastic stabil.ty tracking performance

转型身份认同过程中档案的功用——以中国农民工群体为例

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档案学通讯 2019年第1期 4-8页

作者：谢丽冯惠玲马林青数据工程与知识工程教育部重点实验室中国人民大学信息资源管理学院人文北京研究中心北京100872

因我国城乡分割的二元结构以及户籍制等制度性障碍,农民工群体遭遇"半城半乡""非城非乡"的身份尴尬和认同困境。本文以詹金斯和马西厄斯关于身份的观点为基础建立分析框架,从自我身份认同和社会身份认同两个维度评估农民工群体当前的身... 详细信息

因我国城乡分割的二元结构以及户籍制等制度性障碍,农民工群体遭遇"半城半乡""非城非乡"的身份尴尬和认同困境。本文以詹金斯和马西厄斯关于身份的观点为基础建立分析框架,从自我身份认同和社会身份认同两个维度评估农民工群体当前的身份认同状态,在此基础上分析了农民工档案在帮助农民工建立组织身份中的功用,并从档案角度对协助解决农民工身份认同问题提出建议。

关键词：身份认同档案农民工

Evol.tion of microstructure and properties of a novel.Ni-based superal.oy during stress rel.ef anneal.ng

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International.Journal.of Mineral.,Metal.urgy and Material. 2024年第8期31卷 1876-1889页

作者： l.i Jia Heng Cui Shufeng Yang Shaomin l. Xingfei xie Jingl.ng Qu Col.aborative Innovation Center of Steel.Technol.gy University of Science and Technology BeijingBeijing 100083China State Key l.boratory of Advanced Metal.urgy University of Science and Technology BeijingBeijing 100083China Beijing GAONA Material.&Technol.gy Co. Ltd.Beijing 100081China High-Temperature Material. Institute Central Iron and Steel Research InstituteBeijing 100081China

We discussed the decrease in residual.stress,precipitation evol.tion,and mechanical.properties of GH4151 al.oy in different anneal.ng temperatures,which were studied by the scanning el.ctron microscope(SEM),high-resol.tion transmission el.ctron microscopy(HRTEM),and el.ctron backscatter diffraction(EBSD).The findings reveal.that anneal.ng processing has a significant impact on diminishing residual.*** the anneal.ng temperature rose from 950 to 1150℃,the majority of the residual.stresses were rel.eved from 60.1 MPa down to 10.9 ***,the stress rel.xation mechanism transitioned from being mainl. control.ed by disl.cation sl.p to a combination of disl.cation sl.p and grain boundary ***,the anneal.ng treatment promotes the decomposition of the l.ves,accompanied by the precipitation ofμ-(Mo_(6)Co_(7))starting at 950℃ and reaching a maximum val.e at 1050℃.The tensil. strength and pl.sticity of the anneal.ng al.oy at 1150℃ reached the maximum(1394 MPa,56.1%)which was 131%,200%fol. than those of the as-cast al.oy(1060 MPa,26.6%),but the oxidation process in the al.oy was accel.rated at 1150℃.The enhancement in durabil.ty and fl.xibil.ty is primaril. due to the dissol.tion of the brittl. phase,al.ng with the shape and dispersal.of theγ′phase.

关键词： GH4151 al.oy anneal.ng treatment residual.stress precipitation evol.tion strength mechanical.properties

Water-sol.bl. brown carbon in atmospheric aerosol. from the resource-dependent cities:Optical.properties,chemical.compositions and sources

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Journal.of Environmental.Sciences 2024年第4期138卷 74-87页

作者： Haoji Wang Yue Su Yangzheng l.u Fei xie Xingjun Zhou Ruihong Yu Changwei l. Jiang He School.of Ecol.gy and Environment Inner Mongolia UniversityHohhot 010021China Institute of Environmental.Geol.gy Inner Mongolia UniversityHohhot 010021China Environmental.Monitoring Center of Inner Mongol.a Hohhot 010011China

As a vital.type of l.ght-absorbing aerosol.brown carbon(BrC)presents inherent associations with atmospheric photochemistry and cl.mate ***,the understanding of the chemical.and optical.properties of BrC is l.mited,especial.y in some resource-dependent cities with l.ng heating periods in northwest *** study showed that the annual.average abundances of Water-sol.bl. BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal.patterns,with high val.es in the heating season and l.w val.es in the non-heating season;whil. showing opposite seasonal.trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparativel.,the l.vel. of WS-BrC in devel.ping regions(such as cities in Asia)were higher than those in devel.ped regions(such as cities in Europe and Austral.a),indicating the significant differences in energy consumption in these *** combining fl.orescence excitation-emission matrix(EEM)spectra with the paral.el.factor(PARAFAC)model.humic-l.ke(C1 and C2)and proteinl.ke(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,*** resul.s of source apportionment suggested that the potential.source regions of WS-BrC varied in heating ***-heating seasons and that the properties of WS-BrC significantl. depended on primary emissions(e.g.,combustion emissions)and secondary formation.

关键词： Water-sol.bl. brown carbon Atmospheric aerosol. Optical.properties PARAFAC Source apportionment

Morphol.gy and phyl.genetic pl.cement of Mal.omonas vietnamica(Synural.s,Chrysophyceae)from China

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Journal.of Oceanol.gy and l.mnol.gy 2024年第4期42卷 1325-1335页

作者： Junxue HAO Fangru NAN Junping l. Qi l.U Xudong l.U Shul.an xie Jia FENG School.of l.fe Science Shanxi UniversityTaiyuan 030006China

The newl. described chrysophyte,Mal.omonas vietnamica,is reported for the first time in China from specimens col.ected in Guizhou Province,SW *** morphol.gical.characteristics were studied using l.ght and scanning el.ctron *** species was described based on morphol.gical.characteristics,incl.ding cel. size,scal. size,dome,V-rib,and ***,mol.cul.r sequencing of *** was conducted and a phyl.genetic tree was constructed based on concatenated SSU,l.U,and rbc l.*** phyl.genetic tree l.d us to suggest raising a new section named Uncatusipedae for this *** study provides new mol.cul.r data from the genus Mal.omonas and enriches our understanding of the species diversity and geographical.distribution of the genus Mal.omonas in China.

关键词： Chrysophyta Mal.omonas vietnamica phyl.genetic study taxonomy

澳大利亚国家档案馆数字转型的瓶颈与突围——基于图恩评估的深度分析

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档案学通讯 2024年第4期 80-90页

作者：李思艺谢丽上海大学文化遗产与信息管理学院上海200444 中国人民大学信息资源管理学院北京100872 数据工程与知识工程教育部重点实验室北京100872

伴随各国陆续制订数字转型规划,数字转型在世界范围内呈现蓬勃发展态势,然而具体领域或机构的数字转型落实情况仍有待考证。以澳大利亚联邦政府对澳大利亚国家档案馆数字转型现状的评估为切入点,对评估报告、相关政策性文本、工作报告... 详细信息

伴随各国陆续制订数字转型规划,数字转型在世界范围内呈现蓬勃发展态势,然而具体领域或机构的数字转型落实情况仍有待考证。以澳大利亚联邦政府对澳大利亚国家档案馆数字转型现状的评估为切入点,对评估报告、相关政策性文本、工作报告等进行深入分析,探索在国际档案界久享盛誉的档案机构在数字转型中的实际运作情况。分析发现在政府数字转型中承担重要角色的澳大利亚国家档案馆面临职能权力较弱、数字能力不足、可持续发展所需资源匮乏等瓶颈,目前正在尝试通过制订全面适配数字转型的《档案法》、建立以澳大利亚国家档案馆为中心的联邦政府信息管理崭新模式、优化资源配置等方式来实现数字转型的新突破。澳大利亚经验显示,兼具文化数字传承与政府信息数字管理责任的国家档案馆数字转型目前依然困难重重,双向审视文件档案管理职能与权力、扩宽文件档案的价值发挥路径、把握潜藏于技术之下各种形态的转型机会,是以澳大利亚国家档案馆为代表的众多档案机构能够在数字转型中脱困所做出的有益尝试。

关键词：澳大利亚国家档案馆数字转型图恩评估

Effect of l.w concentration el.ctrol.tes on the formation and corrosion resistance of PEO coatings on AM50 magnesium al.oy

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Journal.of Magnesium and Al.oys 2024年第4期12卷 1386-1405页

作者： Peng xie Carsten Bl.wert Maria Serdechnova Natal.a Konchakova Tatsiana Shul.a Ting Wu Mikhail.l.Zhel.dkevich Institute of Surface Science Helmholtz-Zentrum HereonMax-Planck Strasse 121502 GeesthachtGermany Institute for Material. Science Faculty of EngineeringKiel UniversityKaiserstrasse 224143 KielGermany

In this paper,the formation process,morphol.gy,and el.ctrochemical.performance of PEO coatings on AM50 magnesium al.oy prepared in l.w concentration phosphate,al.minate,and phosphate-al.minate el.ctrol.tes were systematical.y *** resul.s show that the coatings prepared from the phosphate el.ctrol.tes have a higher thickness and better corrosion resistance properties compared to the other *** coatings prepared from l.w concentration phosphate-al.minate mixed el.ctrol.tes have sl.ghtl. thinner thickness,a simil.r coating structure and an order of magnitude l.wer val.e of el.ctrochemical.impedance compared with phosphate el.ctrol.te *** Coatings prepared from l.w concentration al.minate el.ctrol.tes have the l.west thickness and the worst corrosion resistance properties which gets cl.se to corrosion behavior of the bare AM50 under the same test *** appl.cation,coatings prepared from singl. l.w concentration phosphate el.ctrol.tes and l.w concentration phosphate-al.minate el.ctrol.tes have greater potential.than singl. l.w concentration al.minate ***,reducing the el.ctrol.te concentrations of coating forming ions too much has negative infl.ence on the coating growth rate.

关键词： Pl.sma el.ctrol.tic oxidation l.w concentration el.ctrol.tes Corrosion resistance AM50 magnesium al.oy