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Advances in Aerodynamics 2019年第1期1卷 288-300页

作者： G.L.Kolosov A.D.Kosinov a.n.semenov A.A.Yatskikh Khristianovich Institute of Theoretical and Applied Mechanics SB RAS Novosibirsk 630090Russia

The paper presents the experimental results and the results of direct numerical simulation of the development and interaction of two wave trains from two point sources of controlled disturbances in a supersonic boundary layer on a flat plate with an incident flow Mach number of *** were located parallel to the leading edge of the *** the introduction of controlled disturbances into the boundary layer,the normal component of the mass flow rate was varied in the *** the experiment,periodic glow discharges at a frequency of 20 kHz were *** both cases,the disturbances sources worked *** flow rate pulsations were measured and recorded in sections,parallel to the leading edge of the model,near the maximum of disturbances along the boundary *** the experiment,a constanttemperature hot-wire anemometer was *** performing a discrete Fourier transform,the spatial distributions of disturbances,the beta-spectra were determined,and the wave characteristics of the development of disturbances downstream were *** addition,direct numerical simulation of the downstream development of disturbances from a single source was *** work presents a comparison of experimental and theoretical calculated *** paper discusses the effects inherent in the interaction of unstable traveling controlled disturbances from two sources operating synchronously.

关键词： :DnS Computational modeling Supersonic boundary layer Compressibility Discharge Flat plate Hot-wire anemometer Instability Turbulence

Forces of RBC interaction with single endothelial cells in stationary conditions:Measurements with laser tweezers

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Journal of Innovative Optical Health Sciences 2021年第5期4卷 53-63页

作者： Arseniy A.Kapkov Alexey n.semenov Petr B.Ermolinskiy Andrei E.Lugovtsov Alexander V.Priezzhev Faculty of Physics Lomonosov Moscow State UniversityLeninskie GoryMoscow 119991Russia Faculty of Biology Lomonosov Moscow State UniversityLeninskie GoryMoscow 119991Russia

Red blood cells(RBCs)are able to interact and communicate with endothelial cells(ECs).Under some pathological or even normal conditions,the adhesion of RBCs to the endothelium can be ***,the mechanisms and many aspects of the interaction between RBCs and ECs are not fully *** this work,we considered the interaction of single RBCs with single ECs in vitro aiming to quantitatively determine the force of this interaction using laser *** were performed under different concentrations of proaggregant macromolecules and in the presence or absence of tumor necrosis factor(TnF-α)activating the *** have shown that the strength of interaction depends on the concentration of fibrinogen or dextran proaggregant macromolecules in the environment.A nonlinear increase in the force of cells interaction(from 0.4 pn to 21 pn)was observed along with an increase in the fibrinogen con-centration(from 3 mg/mL to 9 mg/mL)in blood plasma,as well as with the addition of dextran macromolecules(from 10 mg/mL to 60 mg/mL).Dextran with a higher molecular mass(500 kDa)enhances the adhesion of RBCs to ECs greater compared to the dextran with a lower molecular mass(70 kDa).With the preliminary activation of ECs with TnF-α,the force of interaction ***,the adhesion of echinocytes to EC compared to discocytes is significantly *** results may help to better understand the process of interaction between RBCs and ECs.

关键词： Endothelial cells red blood cells laser tweezers adhesion

The Sensitivity Adjustment Technique within the Exoskeleton Control System

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Journal of Artificial Intelligence and Technology 2021年第3期1卷 146-152页

作者： I.L.Ermolov M.M.Knyazkov E.A.semenov A.n.Sukhanov Institute for Problems in Mechanics of the Russian Academy of Sciences 101-1 Prospect Vernadskogo119526 MoscowRussia

An exoskeleton system contains a human operator in the control loop,which imposes restrictions on the applied control algorithms and movement *** is the central topic of the latest physical artificial intelligence that links computing,biology,chemistry,material science,and mechanical *** study explores the robotic exoskeleton system that contains a human operator in the control loop,which imposes restrictions on the applied control algorithms and movement *** the moment,there are several tasks in research projects toward exoskeleton control *** tasks include consideration of fatigue of a person arising from the control of the exoskeleton over a long period of ***’s fatigue,as a result of the monotonous operations,leads to the fact that the control efficiency decreases and the positioning error will increase over *** task when controlling using human biopotentials is a compensation of the influence of the operator’s tremor on the control *** addition,a very important factor is the adaptation of actuators to a change in the transient characteristics of external and internal *** paper describes the results of tests of an arm exoskeleton device with DC drive located in the elbow joint and a control algorithm based on an electromyogram of the biceps brachii and triceps brachii of the *** structure and features of the experimental stand developed in the Laboratory of Robotics and Mechatronics of IP Mech RAS are *** sensitivity adjustment technique within the exoskeleton control system is proposed.

关键词： exoskeleton electromyogram control experiment muscles motor control sensitivity tuning

Arctic Sea Ice Variations in the First Half of the 20th Century:A new Reconstruction Based on Hydrometeorological Data

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Advances in Atmospheric Sciences 2024年第8期41卷 1483-1495,1686-1693页

作者： Vladimir A.semenov Tatiana A.ALDOnInA Fei LI noel Sebastian KEEnLYSIDE Lin WAnG A.M.Obukhov Institute of Atmospheric Physics RAS Moscow 119017Russia Institute of Geography RAS Moscow 119017Russia Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway nansen Environmental and Remote Sensing Center Bergen 5007Norway Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The shrinking Arctic sea-ice area(SIA) in recent decades is a striking manifestation of the ongoing climate *** of the Arctic sea ice have been continuously observed by satellites since 1979, relatively well monitored since the 1950s, but are highly uncertain in the earlier period due to a lack of observations. Several reconstructions of the historical gridded sea-ice concentration(SIC) data were recently presented based on synthesized regional sea-ice observations or by applying a hybrid model–empirical approach. Here, we present an SIC reconstruction for the period1901–2019 based on established co-variability between SIC and surface air temperature, sea surface temperature, and sea level pressure patterns. The reconstructed sea-ice data for March and September are compared to the frequently used Had ISST1.1 and SIBT1850 datasets. Our reconstruction shows a large decrease in SIA from the 1920 to 1940 concurrent with the Early 20th Century Warming event in the Arctic. Such a negative SIA anomaly is absent in Had ISST1.1 data. The amplitude of the SIA anomaly reaches about 0.8 mln km^(2) in March and 1.5 mln km^(2) in September. The anomaly is about three times stronger than that in the SIBT1850 dataset. The larger decrease in SIA in September is largely due to the stronger SIC reduction in the western sector of the Arctic Ocean in the 70°–80°n latitudinal zone. Our reconstruction provides gridded monthly data that can be used as boundary conditions for atmospheric reanalyses and model experiments to study the Arctic climate for the first half of the 20th century.

关键词： Arctic sea ice Arctic climate early 20th century warming climate variability

Formation of Rutile nanoparticles from the Condensed Disperse Phase at a Surface of High-Temperature Particles

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Journal of Earth Science and Engineering 2013年第4期3卷 251-262页

作者： nikolay Kh. Kopyt Konstantin semenov nikolay n. Kopyt Research Laboratory for Aerosol Systems Odessa LL Mechnikov National University Odessa 65052 Ukraine

The photos, which are done by electron microscope, of the condensed disperse phase, surrounding high-temperature metal particles are presented. The dependence of concentration of condensed dispersive phase which surrounds a high-temperature metal particle upon the temperature of the particle was obtained. The dependence of concentration of electrons in condensed dispersive phase upon the temperature of the particle was studied. The dependence of an equilibrium charge of a metal particle surrounded with condensed disperse phase on the temperature of a particle in a positive and negative region is presented. The dependence of a charge of a metal particle on time at the fixed temperature is obtained.

关键词： nanoparticles nanotechnologies particles of the titanium.

Self-Assembly and Ordering of C60 on the WO2/W（110） Surface

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nano Research 2011年第2期4卷 194-203页

作者： Sergey A. Krasnikov Sergey I. Bozhko Kevin Radican Olaf Lübben Barry E. Murphy Sundar-Raja Vadapoo Han-Chun Wu Mohamed Abid Valery n. semenov lgor V. Shvets Centre tbr Research on Adaptive nanostrucmres and nanodevices （CRAnn） School of Physics Trinity College Dublin Dublin 2 Ireland Institute of Solid State Physics Russian Academy of Sciences Chernogolovka Russian Federation King Abdullah Institute for nanoteclmology College of Science King Saud University Riyadh 1145l Saudi Arabia

The growth and ordering of C60 molecules on the WO2/W（110） surface have been studied by low-temperature scanning tunnelling microscopy and spectroscopy （STM and STS）, low-energy electron diffraction （LEED）, and density functional theory （DFT） calculations. The results indicate the growth of a well-ordered C60 layer on the WO2/W（110） surface in which the molecules form a close-packed hexagonal structure with a unit cell parameter equal to 0.95 nm. The nucleation of the C60 layer starts at the substrate＇s inner step edges. Low-temperature STM of C60 molecules performed at 78 K demonstrates well-resolved molecular orbitals within individual molecules. In the C60 monolayer on the WO2/W（110） surface, the molecules are aligned in one direction due to intermolecular interaction, as shown by the ordered molecular orbitals of individual C60. STS data obtained from the C60 monolayer on the WO2/W（110） surface are in good agreement with DFT calculations.

关键词： Fullerenes self-assembly tungsten oxide low-temperature scanning tunnelling microscopy scanning tunnellingspectroscopy W(110)

EVALUATIOn OF PERFORMAnCE OF TRIBOTECHnICAL MATERIALS USInG FRICTIOn CRISS-CROSSED CYLInDRICAL SPECIMEnS BY EXPRESS TEST METHOD

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EVALUATION OF PERFORMANCE OF TRIBOTECHNICAL MATERIALS USING ...

Optimization of an Underwater Wireless Sensor network Architecture with Wave Glider as a Mobile Gateway

第三届摩擦疲劳学国际会议

作者： n. A. VOROnIn A. P. semenov Mechanical Engineering Research Institute of the RAS 4 M. Kharitonievsky per.101830 MoscowRussia Mechanical Engineering Research Institute of the RAS 4 M. Kharitonievsky per.101830 MoscowRussia

＜正＞The capabilitn’ of evaluation of tribotechnical properties, bearing abilities and kinds of surface destruction of bulk materials and coatings by results of friction tests of criss-crossed cylindrical specimens are considered. The techniques of the express - evaluation of properties during tests at gradual increase of load in contact from 0 up to settled value are described. It is shown capability of realization at point contact of various variants of interaction of surfaces: sliding, rolling with sliding, rolling, and squeezing. The test data of bulk materials and topocomposites （materials with deposited by vacuum ion plasma technologies coatings of systems Cr-0 and Ti-n） are given. The various kinds of damages and destructions of coatings are revealed. The mechanisms and sources of origination of observable damages and destructions are discussed.

关键词： friction tests elastic strain plastic deformation coatings friction of a sliding rolling friction rolling friction with sliding force of friction coefficient of friction crack disturbance of continuity damage destruction.

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Journal of Marine Science and Application 2022年第2期21卷 179-196页

作者： Tatiana A.Fedorova Vladimir A.Ryzhov nikolay n.semenov Shaharin A.Sulaiman Department of Applied Mathematics and Mathematical Modeling Saint-Petersburg State Marine Technical University3 LotsmanskayaSaint Petersburg 190121Russia Department of Marine Information Systems and Technologies Saint-Petersburg State Marine Technical University3 LotsmanskayaSaint Petersburg 190121Russia Department of Mechanical Engineering Universiti Teknologi PETRONAS32610 Seri IskandarMalaysia

This paper presents an original probabilistic model of a hybrid underwater wireless sensor network(UWSn),which includes a network of stationary sensors placed on the seabed and a mobile *** mobile gateway is a wave glider that collects data from the underwater network segment and retransmits it to the processing *** authors consider the joint problem of optimal localization of stationary network nodes and the corresponding model for bypassing reference nodes by a wave *** optimality of the network is evaluated according to the criteria of energy efficiency and *** influence of various physical and technical parameters of the network on its energy efficiency and on the lifespan of sensor nodes is *** analysis is carried out for networks of various scales,depending on the localization of stationary nodes and the model of bypassing the network with a wave *** a model example,the simulation of the functional characteristics of the network for a given size of the water area is carried *** is shown that in the case of a medium-sized water area,the model of“bypassing the perimeter”by a wave glider is practically feasible,energy efficient and reliable for hourly data *** the case of a large water area,the cluster bypass model becomes more efficient.

关键词： Underwater wireless sensor network(UWSn) Wave glider(WG) Sensor network architecture Mobile gateway Hydroacoustic communication

On “Voice of Sea” Generation Mechanism

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International Journal of Geosciences 2013年第1期4卷 116-128页

作者： Andrew G. semenov The Academician n. n. Andreev Acoustic Institute Russian Academy of Sciences Moscow Russia

Physical model of self-sustained infrasonic air oscillations related to interaction of fresh gale with choppy sea surface is proposed. It is shown that air infrasonic oscillations are expected inside moving 3D cavities in sea surface generated by gale and detected far from its region. Interaction of wind with moving sea wave crests is shown to be of weaker impact on oscillations in far field. For wind velocity in the range from 10 to 40 m/s deepest cavities acquire resonance frequencies in the range of 3.0 - 0.7 Hz, i.e. frequencies much lower than their quarter wavelength resonance frequencies. In the course of oscillations effective wind velocity applied to cavities can achieve value from 0.4 to 0.6 of wind velocity, while air self-sustained oscillations velocity amplitude can run up in the range from 0.2 to 0.3 of wind velocity. Wind intensification leads to oscillations frequency decrease and oscillation energy losses increase with wind velocity cubed. Cavities natural frequencies are transformed due to air attached mass and volume elasticity additional transformation under wind influence in the range from 1.05 to 1.9 with respect to resonance frequencies at rest. Amplitude of self-sustained oscillation in atmosphere is expected to increase with wind velocity cubed, while cavity air oscillation velocity-linear with wind velocity. Wind velocity threshold of an order of 25 - 30 m/s overcome is necessary to observe effect. Spectral peaks on resonance frequencies in the range 0.7 - 2.5 Hz are expected in effect observation. Infrasonic signals observable far from whole gale in atmosphere, sea water thickness and earth crust on self-sustained oscillation frequency and its harmonics frequencies beginning from third harmonic 2.1 - 7.5 Hz are regarded as phenomenon signs.

关键词： Infrasound Sea Surface-Atmosphere Interaction Whole Gale Wind Velocity Oscillation Frequency Sea noise Self-Sustained Oscillations

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步行路径推荐服务开发

步行路径推荐服务开发

作者： semenov Alexander 武汉大学

学位级别：硕士

时至今日,人们使用智能手机上所推荐的最短路径服务,有时候并不是我们真正所需要的.其实只有我们驾驶汽车的时候,智能手机上所提供的最短路径才是我们需要的.但在步行的时候,我们会更多的考虑周围的环境(比如噪声/空气质量/环境是否优... 详细信息

时至今日,人们使用智能手机上所推荐的最短路径服务,有时候并不是我们真正所需要的.其实只有我们驾驶汽车的时候,智能手机上所提供的最短路径才是我们需要的.但在步行的时候,我们会更多的考虑周围的环境(比如噪声/空气质量/环境是否优美以及是否安全等)来决定选择哪条路线步行.在大多数情况下,我们想要穿过恬静优雅的地方,那里绿意盎然,环境优美,阳光明媚.然而,目前的研究只考虑了部分相关的环境因素,并没有把这些因素统一放到一个模型里面统一研究.本文以圣彼得堡为例,通过综合考虑各种环境因素,构架了一个统一的模型,并依据该模型开发了一个简单的导航服务.我设计了一个调查问卷,用来调查一个地方对喜欢步行的人的吸引力.该问卷获得了来自不同年龄和性别的58个人的反馈,所有这些反馈形成了一个城市不同地区的五星评分样本。我基于获得的样本,利用随机森林算法,创建了位置吸引力模型,该模型通过考虑一个地方的喧闹程度,建筑风格,来自社交媒体的照片,离水域的距离,绿化程度,是否是工业区域来度量一个地方所处位置的吸引力程度(很好,一般,不好).模型在实验数据集上,总体上的f1分数约为0.6,好的和坏的f1分数分别为0.83和0.65,取得了较好的效果.基于该模型,我对圣彼得堡所有的人行通道的吸引力程度进行了评估.为了创建导航服务,我们比较了两种路径优化方法:一种是基于经典的Dijkstra最短路径算法,将路径的权重设置为吸引力模型所得到的位置吸引力程度,另一种则使用Yen的k-最短路径算法,在找到的前n个最短路径中寻找位置吸引力均值最大的.通过比较,我发现Dijkstra最短路径算法优于Yen的k-最短路径算法,并且使用加权Dijkstra最短路径算法所得到的最短路径和实际的最短路径长度基本相同(长6%).最后,基于加权的Dijkstra最短路径算法,我设计并开发了导航的原型系统.该系统给出算法推荐的几条步行路径,并给出相关的结果比如路径吸引力程度以及路径步行时间,以便用户进行比较选择.人工分析表明,在城市的各个地方,该系统都能够有效的推荐出相关的路径。

关键词：行人导航步行路线随机森林应用设计