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银行货币储备博弈的强化学习方法

数学杂志 2025年第1期45卷 81-94页

作者：李策中国科学技术大学数学科学学院安徽合肥230026

在大规模银行交互系统中,各银行可通过控制与中央银行的借贷率来使自身对数货币储备尽可能地接近样本均值,从而降低系统性风险发生的概率.然而当状态过程与目标函数的参数未知时,无法直接求解随机微分博弈问题得到纳什均衡.本文结合平... 详细信息

在大规模银行交互系统中,各银行可通过控制与中央银行的借贷率来使自身对数货币储备尽可能地接近样本均值,从而降低系统性风险发生的概率.然而当状态过程与目标函数的参数未知时,无法直接求解随机微分博弈问题得到纳什均衡.本文结合平均场博弈理论与连续时间强化学习的相关方法,构造了一组大规模银行借贷网络中的近似纳什均衡.首先通过求解向前向后耦合Hj.-FPK方程,得到代表银行的平均场均衡策略;再通过所得策略的形式,设计出迭代参数的方法用以刻画参数未知时的近似最优策略;最后通过学到的参数,构造银行数量较大时的近似纳什均衡.

关键词：系统性风险强化学习近似纳什均衡平均场博奔

The use of UAVs for landslide disaster risk research and disaster risk management: a literature review

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j.urnal of Mountain Science 2021年第2期18卷 482-498页

作者： Ricardo j.GARNICA-peÑA Irasema ALCÁNTARA-AYALA Institute of Geography National Autonomous University of Mexico(UNAM)Mexico City 04510Mexico

On a global scale,from 2005 to 2019,there were 275 high-magnitude,low-frequency disasters that involved 14,172 fatalities and four million affected *** patterns have taken place during longer periods of time in recent *** paper aims to analyse the contribution of the international landslide research community to disaster risk reduction and disaster risk management in reference to the use of Unmanned Aerial Vehicles(UAVs)in a literature *** first section notes the relevance of disaster risk research contributions for the implementation of initiatives and strategies concerning disaster risk *** second section highlights background information and current applications of drones in the field of hazards and *** methodology,which included a systematic peer review of j.urnals in the ISI Web of Science and SCOPUS,was presented in the third section,where the results include analyses of the considered *** study concludes that most current scholarly efforts remain rooted in hazards and post-disaster evaluation and *** landslide disaster risk research should be transdisciplinary in order to strengthen participation of the various relevant stakeholders in contributing to integrated disaster risk management at local,subnational,national,regional and global levels.

关键词： UAVs Landslides Disaster risk Landslide research Vulnerability Exposure Disaster risk management

Deciphering Water Oxidation Catalysts: The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： An, Li Li, j.anyi Sun, Yuanmiao Zhu, j.amin Seow, j.stin Zhu Yeow Zhang, Hong Zhang, Nan Xi, Pinxian Xu, Zhichuan j. Yan, Chun-Hua Lanzhou Univ Frontiers Sci Ctr Rare Isotopes Key Lab Nonferrous Met Chem & Resources Utilizat G State Key Lab Appl Organ ChemColl Chem & Chem Eng Lanzhou 730000 Peoples R China Nanyang Technol Univ Sch Mat Sci & Engn Singapore 639798 Singapore Chinese Acad Sci Fac Mat Sci & Energy Engn Shenzhen Inst Adv Technol Inst Technol Carbon Neutral Shenzhen 518055 Peoples R China Yunnan Univ Natl Ctr Int Res Photoelect & Energy Mat Electron Microscopy Ctr Sch Mat & EnergyKey Lab Electromagnet Mat & Devic Kunming 650091 Peoples R China Baotou Res Inst Rare Earths State Key Lab Baiyunobo Rare Earth Resource Res & Baotou 014030 Peoples R China peking Univ Beijing Natl Lab Mol Sci State Key Lab Rare Earth Mat Chem & Applicat PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Chem Beijing 100871 Peoples R China

Demonstrate that the key factor to determine the activity of reconstructed surfaces is the surface chemistry, instead of reconstruction degree using the popular perovskite LaNi1-xFexO3 oxides as model *** content can influence both the surface reconstruction degree, the activation degree, and the activity of reconstructed *** oxygen evolution reaction activity of reconstructed catalysts is primarily governed by the chemistry of the reconstructed surface species. Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction. The surface reconstruction has been widely observed in perovskite catalysts, and the reconstruction degree has been often correlated with the activity enhancement. Here, a systematic study on the roles of Fe substitution in activation of perovskite LaNiO3 is reported. The substituting Fe content influences both current change tendency and surface reconstruction degree. LaNi0.9Fe0.1O3 is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi1-xFexO3 (x = 0.00, 0.10, 0.25, 0.50, 0.75, 1.00) series. The reconstructed LaNi0.9Fe0.1O3 shows a higher intrinsic activity than most reported NiFe-based catalysts. Besides, density functional theory calculations reveal that Fe substitution can lower the O 2p level, which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability. Furthermore, it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree. The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction. This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction perovskite oxides Doping Activation and reconstruction

The nature of the companion of PSR j.719-1438: a white dwarf or an exotic obj.ct?

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Research in Astronomy and Astrophysics 2012年第7期12卷 813-816页

作者： j. E. Horvath Instituto de Astronomia Geofísica e Ciências Atmosfricas - Universidade de So Paulo

We raise the possibility that the very dense, compact companion of PSR j.719-1438, which has a j.piter-like mass, is an exotic quark obj.ct rather than a light helium or carbon white dwarf. The exotic hypothesis naturally explains some of the observed features, and provides quite strong predictions for this system, to be confirmed or refuted in feasible future studies.

关键词： binary pulsars -- exotic matter-- pulsars: individual (PSR j.719-1438)

Cast-rolling force model of multi-roll solid–liquid cast-rolling bonding process for fabricating metal cladding materials

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Chinese j.urnal of Aeronautics 2023年第9期36卷 346-368页

作者： ce j. Huagui HUANG College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Engineering Research center of Advanced Metal Composites Forming Technology and Equipment of Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024China College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004China

Based on twin-roll casting technology and multi-roll groove rolling technology,a Multi-Roll Solid-Liquid Cast-Rolling Bonding(MRSLCRB)process was proposed to fabricate Cu/steel cladding bars,which processes the advantages of short flow and ***,it is a typical 3-D thermal-fluid-mechanics coupled problem,and determining cast-rolling force is difficult during the equipment ***,the geometrical evolution of the cast-rolling area was studied,laying the foundation to establish contact boundary equations and analyze mechanical schematics and metal ***,a 3-D steady-state thermal-fluid coupled simulation model,including casting roll,substrate bar,and cladding metal,was *** Kissing Point(KP)height,average outlet temperature,and process window were predicted,and simulation results of the three-roll layout indicate that the KP distribution along the circumferential direction can be considered ***,the engineering cast-rolling force model was derived based on the differential element method and plane deformation *** accuracy was verified by the 3-D finite element model,and the influences of process layouts and technological parameters on the castrolling force were *** the indirect multi-field coupled analysis method,the temperature–pressure evolution and reasonable process window can be predicted,which provides a significant basis for guiding equipment design and improving product quality.

关键词： Cast-rolling force Kissing point Multi-field coupled Numerical simulation Solid-liquid cast-rolling bonding

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： Christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA j.mes L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain inj.ry(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

Quantum chemical investigation on photodegradation mechanisms of sulfamethoxypyridazine with dissolved inorganic matter and hydroxyl radical

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j.urnal of Environmental Sciences 2017年第7期29卷 85-92页

作者： Shaheen Shah ce Hao State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China Department of Chemistry Karakorum International UniversityGilgit-Baitistan 15100Pakistan

Sulfamethoxypyridazine（SMP） is one of the commonly used sulfonamide antibiotics（SAs）.SAs are mainly studied to undergo triplet-sensitized photodegradation in water under natural sunlight with other coexisting aquatic environmental organic *** this work,SMP was selected as a representative of *** studied the mechanisms of triplet-sensitized photodegradation of SMP and the influence of selected dissolved inorganic matter,i.e.,anions（Br^-,Cl^-,and NO^-_3） and cations ions（Ca^（2＋）,Mg^（2＋）,and Zn^（2＋）） on SMP photodegradation mechanism by quantum chemical *** addition,the degradation mechanisms of SMP by hydroxyl radical（OH·） were also *** creation of SO_2 extrusion product was accessed with two different energy pathways（pathway-1 and pathway-2） by following two steps（step-I and step-II） in the tripletsensitized photodegradation of *** to low activation energy,the pathway-1 was considered as the main pathway to obtain SO_2 extrusion ***-II of pathway-1 was measured to be the rate-limiting step（RLS） of SMP photodegradation mechanism and the effect of the selected anions and cations was estimated for this *** selected anions and cations promoted photodegradation of SMP by dropping the activation energy of *** estimated low activation energies of different degradation pathways of SMP with OH·radical indicate that OH·radical is a very powerful oxidizing agent for SMP degradation via attack through benzene derivative and pyridazine derivative ring.

关键词： Sulfamethoxypyridazine Photodegradation mechanism Dissolved inorganic matter Hydroxyl radical DFT

OptiLam:Design of Optimised Rolling Schedules

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j.urnal of Iron and Steel Research International 2011年第S1期18卷 492-499页

作者： B pea M Arribas A R Carrillo j.I Barbero j.Calvo Tecnalia Foundry and Iron & Steel Unit c/Geldo-Parque Tecnológico de Bizkaia Edificio 700C.P 48160-Derio (Bizkaia)-Espa a Department of Mining Metals and Materials EngineeringMcGill University3610 University StreetMontrealQuebecCanadaH3A 2B2

Nowadays it is known that the thermomechanical schedules applied during hot rolling of flat products provide the steel with improved mechanical *** this work an optimisation tool,OptiLam (OptiLam v.1),based on a predictive software and capable of generating optimised rolling schedules to obtain the desired mechanical properties in the final product is *** includes some well-known metallurgical models which predict microstructural evolution during hot rolling and the transformation austenite/ferrite during the ***,an optimisation algorithm,which is based on the gradient method,has been added,in order to design thermomechanical sequences when a specific final grain size is *** has been used to optimise rolling parameters,such as strain and ***,some of the results of the software validation performed by means of hot torsion tests are presented,showing also the functionality of the ***,the application of classical optimisation models,based on the gradient method,to hot rolling operations,is also discussed.

关键词： rolling schedules optimisation models mechanical properties grain size

Evaluation of biostimulation and Tween 80 addition for the bioremediation of long-term DDT-contaminated soil

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j.urnal of Environmental Sciences 2015年第2期27卷 101-109页

作者： Bibiana Betancur-Corredor Nancy j.Pino Santiago Cardona Gustavo A.peuela GDCON Research Group Faculty of Engineering University Research Headquarters (SIU) University of Antioquia School of Geosciences and Environment Faculty of Mines National University of Colombia School of Microbiology University of Antioquia

The bioremediation of a long-term contaminated soil through biostimulation and surfactant addition was evaluated. The concentrations of 1,1,1-trichloro-2,2-bis（4-chlorophenyl）ethane（DDT） and its metabolites 1,1-dichloro-2,2-bis（4-chlorophenyl） ethane（DDD） and1,1-dichloro-2,2-bis（4-chlorophenyl） ethylene（DDE） were monitored during an 8-week remediation process. Physicochemical characterization of the treated soil was performed before and after the bioremediation process. The isolation and identification of predominant microorganisms during the remediation process were also carried out. The efficiency of detoxification was evaluated after each bioremediation protocol. Humidity and p H and the heterotrophic microorganism count were monitored weekly. The DDT concentration was reduced by 79% after 8 weeks via biostimulation with surfactant addition（B ＋ S） and 94.3%via biostimulation alone（B）. Likewise, the concentrations of the metabolites DDE and DDD were reduced to levels below the quantification limits. The microorganisms isolated during bioremediation were identified as Bacillus thuringiensis, Flavobacterium sp., Cuprivadius sp.,Variovorax soli, Phenylobacterium sp. and Lysobacter sp., among others. Analysis with scanning electron microscopy（SEM） allowed visualization of the colonization patterns of soil particles. The toxicity of the soil before and after bioremediation was evaluated using Vibrio fischeri as a bioluminescent sensor. A decrease in the toxic potential of the soil was verified by the increase of the concentration/effect relationship EC50 to 26.9% and 27.2% for B ＋ S and B, respectively, compared to 0.4% obtained for the soil before treatment and 2.5%by natural attenuation after 8 weeks of treatment.

关键词： DDT Soil Bioremediation Biostimulation Surfactant Toxicity