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From Control Theory to Gravitational Waves

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Advances in Pure Mathematics 2024年第2期14卷 49-100页

作者： jean-francois Pommaret CERMICS Ecole des Ponts Paris Tech Paris France

When d:ξ→η is a linear ordinary differential (Od) or partial differential (Pd) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator d1:η→ξ such that dξ = η implies d1η = 0. When d is involutive, the procedure provides successive first-order involutive operators d1,...,dn when the ground manifold has dimension n. Conversely, when d1 is given, a much more difficult “inverse problem” is to look for an operator d:ξ→η having the generating CC d1η = 0. If this is possible, that is when the differential module defined by d1 is “torsion-free”, that is when there does not exist any observable quantity which is a sum of derivatives of η that could be a solution of an autonomous Od or Pd equation for itself, one shall say that the operator d1 is parametrized by d. The parametrization is said to be “minimum” if the differential module defined by d does not contain a free differential submodule. The systematic use of the adjoint of a differential operator provides a constructive test with five steps using double differential duality. We prove and illustrate through many explicit examples the fact that a control system is controllable if and only if it can be parametrized. Accordingly, the controllability of any Od or Pd control system is a “built in” property not depending on the choice of the input and output variables among the system variables. In the Od case and when d1 is formally surjective, controllability just amounts to the formal injectivity of ad(d1), even in the variable coefficients case, a result still not acknowledged by the control community. Among other applications, the parametrization of the Cauchy stress operator in arbitrary dimension n has attracted many famous scientists (G. B. Airy in 1863 for n = 2, J. C. Maxwell in 1870, E. Beltrami in 1892 for n = 3, and A. Einstein in 1915 for n = 4).

关键词： differential Operator differential Sequence Killing Operator Riemann Operator Bianchi Operator Cauchy Operator Control Theory Controllability Elasticity General Relativity

Multi-source information fusion:Progress and future

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Chinese Journal of Aeronautics 2024年第7期37卷 24-58页

作者： Xinde LI Fir dUNKIN jean dEZERT School of Automation Southeast UniversityNanjing 210008China Nanjing Center for Applied Mathematics Nanjing 211135China Key Laboratory of Measurement and Control of CSE Ministry of EducationNanjing 210096China Southeast University Shenzhen Research Institute Shenzhen 518063China Information Modeling and Processing department ONERAPalaiseau 92320France

Multi-Source Information Fusion(MSIF),as a comprehensive interdisciplinary field based on modern information technology,has gained significant research value and extensive application prospects in various domains,attracting high attention and interest from scholars,engineering experts,and practitioners *** achieving fruitful results in both theoretical and applied aspects over the past five decades,there remains a lack of comprehensive and systematic review articles that provide an overview of recent development in *** light of this,this paper aims to assist researchers and individuals interested in gaining a quick understanding of the relevant theoretical techniques and development trends in MSIF,which conducts a statistical analysis of academic reports and related application achievements in the field of MSIF over the past two decades,and provides a brief overview of the relevant theories,methodologies,and application domains,as well as key issues and challenges currently ***,an analysis and outlook on the future development directions of MSIF are presented.

关键词： Multi-sensor system Information fusion Artificial intelligence Pattern recognition Human-machine integration

Tanaka Formula and Local Time for a Class of Interacting Branching Measure-valued diffusions

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1059-1098页

作者： donald A.dAWSON jean VAILLANCOURT Hao WANG School of Mathematics and Statistics Carleton UniversityOttawaCanada department of decision Sciences HECMontrealCanada department of Mathematics University of OregonEugeneUSA

We construct superprocesses with dependent spatial motion(SdSMs)in Euclidean spaces R^(d)with d≥1 and show that,even when they start at some unbounded initial positive Radon measure such as Lebesgue measure on R^(d),... 详细信息

关键词： Measure-valued diffusions stochastic partial differential equations superprocesses branching processes local time Tanaka formula

High-performance nickel metal hydride battery anode with enhanced durability and excellent low-temperature discharge capability

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Nano Research 2024年第10期17卷 8819-8825页

作者： Zhitao Chen Huitian Liu jean Nei Nian Liu School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30332USA GP Batteries HongkongChina

Current AB_(5)-type hydrogen storage alloys employed in nickel-metal hydride(NiMH)batteries exhibit exceptional low-temperature discharge performance but suffer from limited cycle life and insufficient high-temperature *** overcome these challenges,we introduce a hydrothermal synthesized LaF_(3)coating layer on the surface of the AB_(5)anode *** LaF_(3)coating layer adds a protective barrier for the active material,significantly improving the battery's cycle life and high-temperature *** findings indicate that(1)the LaF_(3)coated anode demonstrates an extended cycle life with increased specific capacity and a capacity retention of 88%after 40 cycles of abusive overcharging and rapid discharging at room temperature.(2)The synthesized anode exhibits a 97%recovery of its specific capacity of 292.7 mAh/g following 144 h of high-temperature storage.(3)The low-temperature discharge capacity of the synthesized anode remains on par with the pristine AB_(5)alloy at 230.4 mAh/g in a-40℃*** research presents a significant advancement in hydrogen storage alloy coatings and offers valuable insights for designing electrodes in NiMH batteries.

关键词： nickel metal hydride(NiMH)batteries hydrothermal synthesis lanthanum fluoride discharge capacity low temperature

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Sustainable Ride

ChinAfrica 2024年第9期16卷 54-55页

作者： jean d’AMOUR MBONYINSHUTI 不详

Chinese electric vehicle makers fuel Rwanda’s drive for pollution-free *** a growing demand to electrify Rwanda’s public transport,companies are rushing into the sector to import electric vehicles(EVs)and related se... 详细信息

关键词： companies Sustainable China.

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构建安全连接,筑牢通信行业高质量发展底座

数字经济 2024年第4期 93-95页

作者： jean-francois Ouillet 泰雷兹集团

身处数字化时代,以新一代信息通信技术为核心的物联网(IoT)正在重塑各行各业,为数字经济发展注入强劲动力;同时,也在改变着每个人与周围世界互动的方式,为日常生活带来更多便捷选择。物联网不断为行业数字化转型提供新支撑、为数字经济... 详细信息

身处数字化时代,以新一代信息通信技术为核心的物联网(IoT)正在重塑各行各业,为数字经济发展注入强劲动力;同时,也在改变着每个人与周围世界互动的方式,为日常生活带来更多便捷选择。物联网不断为行业数字化转型提供新支撑、为数字经济发展拓展新空间,整个市场也在持续探索更灵活便捷、安全可靠的连接方式,以应对新挑战。

关键词：信息通信技术通信行业数字化转型数字化时代安全连接强劲动力灵活便捷连接方式

Modelling the viscoplastic behaviour of Callovo-Oxfordian claystone with consideration of damage effect

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 303-316页

作者： Hao Wang Yu-Jun Cui Minh Ngoc Vu jean Talandier Ecole des Ponts ParisTech Laboratoire Navier/CERMES6 et 8 avenue Blaise PascalMarne La Vallée cedex 277455France Andra R&D DepartmentChâtenay-Malabry92290France

In order to evaluate the performance of deep geological disposal of radioactive waste,an underground research laboratory(URL)was constructed by Andra in the Callovo-Oxfordian(COx)claystone formation at the Meuse/Haute-Marne(MHM).The construction of URL induced the excavation damage of host formations,and the ventilation in the galleries desaturated the host formation close to the gallery ***,it is expected that the mechanical behaviour of COx claystone is *** study presents a constitutive model developed to describe the viscoplastic behaviour of unsaturated and damaged COx *** this model,the unsaturation effect is considered by adopting the Bishop effective stress and the van Genuchten(VG)water retention *** terms of the viscoplastic behaviour,the nonstationary flow surface(NSFS)theory for unsaturated soils is used with consideration of the coupled effects of strain rate and suction on the yield stress.A progressive hardening law is ***,a non-associated flow rule is used,which is similar to that in Barcelona basic model(BBM).In addition,to describe the damage effect induced by suction change and viscoplastic loading,a damage function is defined based on the crack volume *** damage function contains two variables:unsaturated effective stress and viscoplastic volumetric strain,with the related parameters determined based on the mercury intrusion porosimetry(MIP)*** the model validation,different tests on COx claystone under different loading paths are *** between experimental and simulated results indicated that the present model is able to well describe the viscoplastic behaviour of damaged COx claystone,including swelling/shrinkage,triaxial extension and compression,and triaxial creep.

关键词： Callovo-Oxfordian(COx)claystone Excavation damage Time-dependent behaviour Suction Viscoplastic model

21世纪全球新建水库编目:丰度、热点区及总蓄水量

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Science Bulletin 2024年第14期69卷 2179-2182页

作者：范晨雨宋春桥 Jida Wang Yongwei Sheng 蔺亚玲苑春雨 Md Safat Sikder jean-francois Crétaux 刘凯陈探曾繁轩柯灵红 Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China University of Chinese Academy of Sciences Nanjing(UCASNJ)Nanjing 211135China department of Geography and Geographic Information Science University of Illinois Urbana-ChampaignUrbana IL 61801USA department of Geography and Geospatial Sciences Kansas State UniversityManhattan KS 66506USA department of Geography University of CaliforniaLos Angeles CA 90095USA Laboratoire d’Études en Géophysique et Océanographie Spatiales(LEGOS) CNES-IRD-CNRS-UT3Universitéde ToulouseToulouse 31401France College of Hydrology and Water Resources Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China

dams and reservoirs play an essential role in regulating and managing water *** the middle of the 20th century,the growing demand for water and hydropower has led to an unprecedented boom in reservoir construction worldwide[1,2].Meanwhile,reservoir construction has also resulted in a variety of ecological and socioeconomic impacts[3–5].Reservoirs transform natural flow regimes into conditions favored by human *** associated flow regulations,especially in reservoirs constructed in recent decades(e.g.,after 2000)with greater seasonal variability[6,7],represent a strong human-induced alteration of the hydrologic *** reservoir construction continues to boom in many parts of the world,an up-to-date and openaccess inventory of reservoirs worldwide remains critically desired.

关键词： reservoir reservoirs alteration

Lateral ring compression test applied to a small caliber steel jacket:Identification of a constitutive model

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defence Technology（防务技术） 2024年第6期36卷 133-148页

作者： Yann Coget Yael demarty Christophe Czarnota Anthony Bracq jean-Sebastien Brest Alexis Rusinek French-German Research Institute of Saint-Louis 5 Rue Du General Cassagnou68300 Saint-LouisFrance Laboratoire d'Etude des Microstructures et de Mecanique des Materiaux(LEM3) CNRSUniversite de LorraineArts&Metiers ParisTechF-57000 MetzFrance

The evolution of threats and scenarios requires continuous performance improvements of ballistic protections for armed *** a modeling point of view,it is necessary to use sufficiently precise material behavior models to accurately describe the phenomena observed during the impact of a projectile on a protective *** this context,the goal of this paper is to characterize the behavior of a small caliber steel jacket by combining experimental and numerical *** experimental method is based on the lateral compression of ring specimens directly machined from the thin and small *** speeds and temperatures are considered in a quasi-static regime in order to reveal the strain rate and temperature dependencies of the tested *** Finite Element Updating Method(FEMU)is *** results are coupled with an inverse optimization method and a finite element numerical model in order to determine the parameters of a constitutive model representative of the jacket *** of the present model are verified against experimental results and a parametric study as well as a discussion on the identified material parameters are *** results indicate that the strain hardening parameter can be neglected and the behavior of the thin steel jacket can be described by a modeling without strain hardening sensitivity.

关键词： Full metal jacket ammunition Lateral ring compression Inverse identification Numerical simulation