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

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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

Energy flow problem solution based on state estimation approaches and smart meter data

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Global Energy Interconnection 2022年第5期5卷 551-563页

作者： Andrew V.Pazderin Ilya D.polyakov Vladislav O.Samoylenko Department of Automated Electrical Systems Ural Federal UniversityYekaterinburgMira 19Russia System Operator of United Power System YekaterinburgTolmacheva 6Russia

Accurate electric energy(EE)measurements and billing estimations in a power system necessitate the development of an energy flow distribution *** paper summarizes the results of investigations on a new problem related to the determination of EE flow in a power system over time intervals ranging from minutes to *** problem is referred to as the energy flow problem(EFP).Generally,the grid state and topology may fluctuate over *** attempt to use instantaneous(not integral)power values obtained from telemetry to solve classical electrical engineering equations leads to significant modeling errors,particularly with topology changes.A promoted EFP model may be suitable in the presence of such topological and state ***,EE flows are determined using state estimation approaches based on direct EE measurement data in Watt-hours(Volt-ampere reactive-hours)provided by electricity *** EFP solution is essential for a broad set of applications,including meter data validation,zero unbalance EE billing,and nontechnical EE loss check.

关键词： Automatic meter reading Advanced metering infrastructure Energy flow distribution Electricity losses Energy measurements State estimation.

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

Comprehensive semen examination in patients with pancreatic-sufficient and pancreatic-insufficient cystic fibrosis

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Asian Journal of Andrology 2023年第5期25卷 591-597页

作者： Anna O Sedova Maria I Shtaut Elizaveta E Bragina Tatyana M Sorokina Galina V Shmarina Marina V Andreeva Lyubov E Kurilo Stanislav A Krasovskiy Aleksander V polyakov vya.hesla. B Chernykh Research Centre for Medical Genetics Russia Moscow 115522

We examined a cohort of 93 cystic fibrosis(CF)male patients who were pancreatic-sufficient(PS-CF;n=40)or pancreatic-insufficient(PI-CF;n=53).Complex semen examination was performed,including standard semen analysis,quantitative karyological analysis(QKA)of immature germ cells(IGCs),transmission electronic microscopy(TEM),biochemical analysis,and sperm DNA fragmentation by terminal deoxynucleotidyl transferase-mediated dUTP nickend labeling(TUNEL)*** was diagnosed in 83(89.2%)*** other 10(10.8%)patients were found to be nonazoospermic and showed various spermatological diagnoses(asthenozoospermia,n=2;asthenoteratozoospermia,n=3;oligoasthenozoospermia,n=1;oligoasthenoteratozoospermia,n=3;and normozoospermia,n=1)with no specific morphological *** was detected in 89.2%azoospermic and 30.0%nonazoospermic *** seminal pH(30%)of spermatozoa with noncondensed(“immature”)chromatin was revealed in 2 of 6 nonazoospermic semen samples analyzed by TEM.

关键词： congenital bilateral agenesia/aplasia of vas deferens cystic fibrosis cystic fibrosis transmembrane conductance regulator gene semen spermatozoa

提高KF-AlF_(3)-Al_(2)O_(3)熔体中Cu-Al基阳极的耐腐蚀性

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Transactions of Nonferrous Metals Society of China 2022年第1期32卷 354-363页

作者： Sai Krishna PADAMATA Andrey YASINSKIY Aleksandr SHABANOV Timofey BERMESHEV 杨酉坚王兆文曹导 Peter polyakov Laboratory of Physics and Chemistry of Metallurgical Processes and Materials Siberian Federal UniversityKrasnoyarskRussia Laboratory of Molecular Spectroscopy Krasnoyarsk Science Center SB RASKrasnoyarskRussia 东北大学冶金学院沈阳110819

采用恒电流和动电位极化技术研究经预氧化的和未经预氧化的Cu-Al基阳极(Cu-10Al和Cu-9.8Al-2Mn)在KF-AlF_(3)-Al_(2)O_(3)熔体中的阳极行为。将合金在700℃下进行短时间(8 h)氧化,然后在800℃下施以0.4 A/cm^(2)的电流密度进行1 h恒电... 详细信息

采用恒电流和动电位极化技术研究经预氧化的和未经预氧化的Cu-Al基阳极(Cu-10Al和Cu-9.8Al-2Mn)在KF-AlF_(3)-Al_(2)O_(3)熔体中的阳极行为。将合金在700℃下进行短时间(8 h)氧化,然后在800℃下施以0.4 A/cm^(2)的电流密度进行1 h恒电流极化。测定扫描速率为0.01 V/s的动电位曲线。对在阳极表面冻结的熔体样品进行XRD分析,并在实验后对阳极进行SEM分析,以研究合金表面形成的氧化皮的物相。所有阳极材料的稳态电位都在2.30~2.50 V(vs Al/AlF_(3))范围内。根据动电位极化获得的数据计算阳极的腐蚀速率。结果表明,经预氧化的阳极比未经预氧化的阳极具有更低的腐蚀速率。

关键词：惰性阳极钾冰晶石 Cu-Al合金腐蚀铝电解析氧电极

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

考虑误差和齿面摩擦随机性的直齿圆柱齿轮副振动特性分析

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机械传动 2022年第2期46卷 34-41页

作者：高在达李胜波符升平 polyakov Roman 厦门理工学院机械与汽车工程学院福建厦门361024 集美大学海洋装备与机械工程学院福建厦门361021 OrelStateUniversityNamedafterI.S.Turgenev RussiaOrel State 302026

针对考虑误差和齿面摩擦参数随机性的齿轮振动特性不明确的问题,综合统计法和集中质量法,数值研究误差和齿面摩擦参数的随机特性,分析轮齿误差对齿面摩擦参数的影响,建立计及误差和齿面摩擦参数随机性的直齿轮传动弯扭耦合振动模型;采用... 详细信息

针对考虑误差和齿面摩擦参数随机性的齿轮振动特性不明确的问题,综合统计法和集中质量法,数值研究误差和齿面摩擦参数的随机特性,分析轮齿误差对齿面摩擦参数的影响,建立计及误差和齿面摩擦参数随机性的直齿轮传动弯扭耦合振动模型;采用4阶龙格库塔法进行数值求解,得到齿轮传动的振动响应,探析齿轮误差和齿面摩擦参数随机性对齿轮振动特性的影响。结果表明,考虑误差和齿面摩擦随机性后,在两者的作用下齿轮动力学响应在频域与相图上表现出更为复杂的随机性,其中误差随机性对于齿轮系统动力学稳定性的干扰更强。研究结果为齿轮传动的动态设计提供理论参考。

关键词：随机误差齿面摩擦齿轮传动齿轮动力学