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Science China(Information Sciences) 2024年第8期67卷 24-34页

作者： Siyuan WANG Andrey polyakov Min LI Gang ZHENG Driss BOUTAT INSA Centre Val de Loire INRIA

The objective of the invariant ellipsoid method is to minimize the smallest invariant and attractive set of a linear control system operating under the influence of bounded external disturbances. This study extends the application of this method to address the leader-following consensus problem. Initially, a linear control protocol is designed for the multi-agent system in the absence of disturbances. Subsequently, in the presence of bounded disturbances, by employing a similar linear control protocol, a necessary and sufficient condition is introduced to derive the optimal control parameters for the multi-agent system such that the state of followers converges to and remains in a minimal invariant ellipsoid around the state of the leader.

关键词： multi-agent system leader-following consensus invariant ellipsoid disturbance

Generalized equation for calculating rock cutting efficiency by pulsed water jets

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 867-873页

作者： Andrey polyakov Aleksandr Zhabin Eugene Averin Aleksey polyakov Department of Geotechnologies and Underground Construction Tula State UniversityTula300012Russia OOO Skuratovsky Experimental Plant Tula300911Russia OOO Industrial Safety Examination Tula300600Russia

One of the promising methods for rock cutting technology is the use of high-speed water *** order to improve the cutting capacity of water jets without increasing the hydraulic power of equipment,pulsed water jets are basically used to increase the rock cutting ***,there are no mature recommendations for selection of rational parameters,and the relationship between indicators of rock cutting efficiency and parameters of pulsed water jet is still not *** this context,we aimed at developing a generalized equation for calculating rock cutting efficiency,in which all the major parameters in consideration of rock cutting process are ***,a calibration of the rational parameters of rock cutting by pulsed water jets was *** results are likely helpful for increasing productivity and reducing energy consumption.

关键词： Pulsed water jets Rock cutting Water jet technology Generalized equation Depth of cut

Geochemistry of cryoconite and soils in the Central Caucasus region and its environmental implications

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Journal of Mountain Science 2021年第12期18卷 3109-3124页

作者： Ivan KUSHNOV Evgeny ABAKUMOV Rustam TEMBOTOV vya.hesla. polyakov Saint Petersburg State University 7/9 University EmbankmentSt Petersburg 199034Russian Federation Tembotov Institute of Ecology of Mountain Territories Russian Academy of Sciences37-a I.Armand Str.Nalchik360051Russian Federation

Climate change and deglaciation are active processes in current changing *** the Central Caucasus region rapid degradation of glaciers is caused often by the formation of superficial blackcolored *** plays a crucial role in changing ecosystems and may contribute to the formation of primary soils after glacier *** the past 20 years,the frequency of mudflows and other dangerous mountain events have increased in the Central Caucasus,which is associated with the glacial *** of tourism results in increasing of traffic,recreational activity and environment *** of the cryoconites geochemical properties in comparison with other types of sediments and local soils is crucial for investigation of geochemistry and contamination state of superficial glacial *** environmental aspect is important in terms of the Central Caucasus settlements safety under conditions of deglaciation and anthropogenic *** sediments studied(cryoconite,mudflow,moraine)were sampled at Garabashi and Skhelda glaciers as well as some local soils at the Baksan *** materials were investigated in terms of physicochemical and agrochemical *** concentrations of trace elements(Cu,Pb,Zn,Ni,Cd)were also determined and contamination indices(geoaccumulation index-Igeo,contamination factor-CF and degree of contamination-Cdegree)were used to evaluate the pollution status of studied *** obtained shows much higher content of organic carbon in soils(up to 7.82%)in comparison with cryoconite(max.1.63%)due to presence of vegetation,however,the basal respiration values in some cases were similar betweenсryoconite and soils,indicating high rates of microbial activity in a cryoconite *** was found that almost all materials studied have sandy *** sediments on both of the glaciers are enriched with phosphorus,high values of K_(2)O(max.298 mg·kg^(-1))and N-NH4(max.

关键词： Cryoconite Trace elements Entisols Contamination Central Caucasus

Sediments from cryoconite holes and dirt cones on the surface of Svalbard glaciers:main chemical and physicochemical properties

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Acta Geochimica 2023年第2期42卷 346-359页

作者： Timur Nizamutdinov Bulat Mavlyudov vya.hesla. polyakov Evgeny Abakumov Department of Applied Ecology Faculty of BiologySt.Petersburg State University16th Liniya V.O.29St.PetersburgRussia 199178 Russian Academy of Sciences Institute of GeographyMoscowRussia 119017

The paper discussed the influence of the forms of sediment accumulation on the surface of glaciers on their chemical and physicochemical *** materials sampled from the surface of five glaciers of the Svalbard Archipelago was *** studied such forms of sediment accumulation as dirt cones-the ice core covered with sediments and cryoconite holes-hollows on the glacier surface containing cryoconite *** such as total organic carbon content,microbiological activity,pH,the content of mobile forms of potassium and phosphorus,and concentrations of heavy and trace metals were ***,mesomorphological studies were carried out and the polydisperse composition of the sediments was *** to the results of this work,it was found that the content of organic carbon in the material selected from dirt cones and cryoconite holes can be up to 2.5%,but the content of clay particles in it is mainly at the 10–15%*** concentrations are up to 250 mg/kg,and phosphorus is up to 800 mg/*** content of metals is typical or lower than in the previously published *** main influence on the chemical composition of materials has a geographical factor of the sampling site,rather than the form of material accumulation.

关键词： Arctic Soil-like bodies Glacier sediments Accumulation

Advances in soil erosion research:Mechanisms,modeling and applications-A special issue in honor of *** Nearing

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International Soil and Water Conservation Research 2023年第4期11卷 589-591页

作者： Viktor polyakov Claire Baffaut Vito Ferro Scott Van Pelt Southwest Watershed Research Center USDA-ARS2000 E Allen RdTucsonAZ85718USA Cropping Systems and Water Quality Research Unit USDA-ARS241 Ag Engineering BuildingUniversity of MissouriColumbiaMO65211USA Department of Agricultural Food and Forest SciencesUniversity of PalermoViale Delle ScienzeBuilding 490128PalermoItaly Cropping Systems Research Laboratory USDA-ARS38104th StLubbockTX79401USA

*** Long-term sustainability of soils is one of the critical challenges facing *** erosion is an intrinsic geomorphological pro-cess,which if accelerated can threaten natural ecosystems and agri-culture through loss of productivity,sedimentation,and associated *** efforts to mitigate these problems require changes in management practices and large *** puts special emphasis on understanding physical processes driving soil erosion,developing techniques for accurate estimation of erosion rates and its on-site and off-site impacts,as well as devel-oping new modeling,prediction,and management tools.

关键词： soil erosion driving

CONJUGATE MODEL FOR HEAT AND MASS TRANSFER OF POROUS WALL IN THE HIGH TEMPERATURE GAS FLOW

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Acta Mechanica Sinica 2001年第3期17卷 245-250页

作者： A.F.polyakov D. L. Reviznikov 沈青唐锦荣魏叔如 Institute of High Temperatures Russian Academy of Sciences Moscow Russia Moscow Aviation Institute (Technical University) Moscow Russia LHD Institute of Mechanics Chinese Academy of Science Beijing China 100080

Heat and mass transfer of a porous permeable wall in a high temperature gas dynamical flow is considered. Numerical simulation is conducted on the ground of the conjugate mathematical model which includes filtration and heat transfer equations in a porous body and boundary layer equations on its surface. Such an approach enables one to take into account complex interaction between heat and mass transfer in the gasdynamical flow and in the structure subjected to this flow. The main attention is given to the impact of the intraporous heat transfer intensity on the transpiration cooling efficiency.

关键词： heat and mass transfer porous media conjugate model high temperature gas flow

Ocean stratification and sea-ice cover in Barents and Kara seas modulate sea-air methane flux:satellite data

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Advances in Polar Science 2021年第2期32卷 118-140页

作者： Leonid YURGANOV Dustin CARROLL Andrey PNYUSHKOV Igor polyakov Hong ZHANG University of Maryland Baltimore County(ret) BaltimoreMDUSA Moss Landing Marine Laboratories San JoséState UniversityCAUSA International Arctic Research Center University of Alaska FairbanksAKUSA Jet Propulsion Laboratory California Institute of TechnologyCAUSA

The diverse range of mechanisms driving the Arctic amplification and global climate are not completely understood and,in particular,the role of the greenhouse gas methane(CH4)in the Arctic warming remains *** sources of methane at the ocean seabed in the Barents Sea and other polar regions are well ***,some of those publications suggest that negligible amounts of methane fluxed from the seabed enter the atmosphere,with roughly 90%of the methane consumed by *** in situ observations are taken during summer,which is favorable for collecting data but also characterized by a stratified water *** present perennial observations of three Thermal IR space-borne spectrometers in the Arctic between 2002 and *** to estimates derived from the data synthesis ECCO(Estimating the Circulation and Climate of the Ocean),in the ice-free Barents Sea the stratification in winter weakens after the summer strong *** convection,storms,and turbulent diffusion mix the full-depth water ***4 excess over a control area in North Atlantic,measured by three sounders,and the oceanic Mixed Layer Depth(MLD)both maximize in winter.A significant seasonal increase of sea-air exchange in ice-free seas is *** amplitude of the seasonal methane cycle for the Kara Sea significantly increased since the beginning of the *** may be explained by a decline of ice concentration *** annual CH4 emission from the Arctic seas is estimated as 2/3 of land *** Barents/Kara seas contribute between 1/3 and 1/2 into the Arctic seas annual emission.

关键词： satellite data greenhouse gases methane Thermal IR(TIR) Arctic

On a Perturbation Method for Stochastic Parabolic PDE

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Communications in Mathematics and Statistics 2015年第2期3卷 215-226页

作者： Donald J.Estep Peter L.polyakov Department of Statistics Colorado State University205 Statistics BuildingFort CollinsCO 80523USA Department of Mathematics University ofWyoming1000 EUniversityAveLaramieWY82071USA

In this article,we address two issues related to the perturbation method introduced by Zhang and Lu(J Comput Phys 194:773-794,2004),and applied to solving linear stochastic parabolic *** issues are the construction of... 详细信息

关键词： Stochastic parabolic differential equation Karhunen-Loève expansion

Variations of the Magnetosphere Resonance Frequencies During Magnetic Storm of July 15-16,2000

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空间科学学报 2005年第5期25卷 387-392页

作者： A. Potapov A. polyakov T. Polyushkina H. Zhao Institute of Solar-Terrestrial Physics Siberia Branch Russian Academy of Sciences Irkutsk 664033 Russia National Microwave Remote Sensing Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences

ULF observations at two mid-latitude sites during the large geomagnetic storm of July 15-16,2000 were used to trace variations of resonance frequencies of the field line resonators. A brief description of the geomagnetic disturbance as it was observed on the ground, at the geostationary orbit, and before the Earth's bow shock is given. Then a detailed study of ULF dynamic spectra from Borok and Mondy is performed for8 succesive 6-hour intervals of July 15 and 16. In conclusion some tasks for the future work are listed.

关键词：等离子体磁场磁气圈空间气候

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换挡工况下湿式换挡离合器变胞机理

浙江大学学报（工学版） 2019年第4期53卷 628-637页

作者：符升平李胜波罗宁 Roman Nikolaevich polyakov 厦门理工学院机械与汽车工程学院福建厦门361024 奥廖尔国立大学俄罗斯奥廖尔州302026

针对目前难以全面描述湿式换挡离合器变结构、非定常和非数值的变拓扑工作过程的问题,基于湿式换挡离合器工作特性的分析,定义摩擦对偶片各构态的约束函数,建立摩擦对偶片变胞器,提出湿式换挡离合器变胞的图形描述方法.采用矩阵分析法,... 详细信息

针对目前难以全面描述湿式换挡离合器变结构、非定常和非数值的变拓扑工作过程的问题,基于湿式换挡离合器工作特性的分析,定义摩擦对偶片各构态的约束函数,建立摩擦对偶片变胞器,提出湿式换挡离合器变胞的图形描述方法.采用矩阵分析法,以约束函数为元素,推导离合器各构态的邻接矩阵,解析相邻构态转换时对应的变胞函数和变胞方程,构建湿式换挡离合器工作的变胞拓扑模型,揭示换挡离合器工作状态转换的变胞机理.基于变胞机理分析,提出更直观和简便的离合器动力学建模方法,通过对比分析离合器转速变化规律的试验和仿真结果,表明该方法的准确性和可行性.

关键词：湿式换挡离合器变胞机理约束函数摩擦对偶片变胞方程