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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 2.5.Sources were located parallel to the leading edge of the model.For the introduction of controlled disturbances into the boundary layer,the normal component of the mass flow rate was varied in the calculations.In the experiment,periodic glow discharges at a frequency of 20 kHz were used.In both cases,the disturbances sources worked synchronously.Mass 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 layer.In the experiment,a constanttemperature hot-wire anemometer was used.After 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 estimated.In addition,direct numerical simulation of the downstream development of disturbances from a single source was performed.The work presents a comparison of experimental and theoretical calculated data.The 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

以波浪滑翔机为移动网关的水下无线传感器网络架构优化

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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 gateway.The mobile gateway is a wave glider that collects data from the underwater network segment and retransmits it to the processing center.The authors consider the joint problem of optimal localization of stationary network nodes and the corresponding model for bypassing reference nodes by a wave glider.The optimality of the network is evaluated according to the criteria of energy efficiency and reliability.The influence of various physical and technical parameters of the network on its energy efficiency and on the lifespan of sensor nodes is analyzed.The 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 glider.As a model example,the simulation of the functional characteristics of the network for a given size of the water area is carried out.It 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 measurements.In 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

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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

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 observed.Presently,the mechanisms and many aspects of the interaction between RBCs and ECs are not fully understood.In 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 tweezers.Measurements were performed under different concentrations of proaggregant macromolecules and in the presence or absence of tumor necrosis factor(TnF-α)activating the ECs.We 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 increases.Also,the adhesion of echinocytes to EC compared to discocytes is significantly higher.These 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 speed.Robotics is the central topic of the latest physical artificial intelligence that links computing,biology,chemistry,material science,and mechanical engineering.This 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 speed.At the moment,there are several tasks in research projects toward exoskeleton control algorithms.These tasks include consideration of fatigue of a person arising from the control of the exoskeleton over a long period of time.Operator’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 time.Another task when controlling using human biopotentials is a compensation of the influence of the operator’s tremor on the control signal.In addition,a very important factor is the adaptation of actuators to a change in the transient characteristics of external and internal forces.This 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 operator.The structure and features of the experimental stand developed in the Laboratory of Robotics and Mechatronics of IP Mech RAS are shown.The sensitivity adjustment technique within the exoskeleton control system is proposed.

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

热力学抑制剂与CO_2同注开采天然气水合物的实验研究

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天然气工业 2017年第12期37卷 40-46页

作者： Khlebnikov V.n. Gushchin P.A. Antonov S.V. Mishin A.S. 梁萌 Khamidullina I.V. Zobov P.M. Likhacheva n.V. semenov A.P. Vinokurov V.A. 俄罗斯古勃金国立石油天然气大学

为解决CO_2置换法开采天然气水合物(以下简称水合物)过程中出现的置换速率慢、置换程度不高等问题,提出了将CO_2置换法与热力学抑制剂法组合使用的技术思路,即"抑制剂—置换法"。在实验室利用填砂管模型在岩心驱替装置上测定了CO_2与不... 详细信息

为解决CO_2置换法开采天然气水合物(以下简称水合物)过程中出现的置换速率慢、置换程度不高等问题,提出了将CO_2置换法与热力学抑制剂法组合使用的技术思路,即"抑制剂—置换法"。在实验室利用填砂管模型在岩心驱替装置上测定了CO_2与不同浓度的甲醇溶液在同注的情况下CH_4水合物的分解效果。结果表明:(1)甲醇的浓度对水合物开采效果起着决定性作用,甲醇溶液浓度越小,CH_4水合物的分解越弱,其变化趋势表现为以CH_4水合物的分解为主导转变为以CO_2水合物的生成为主导;(2)当CO_2与浓度为20.8%的甲醇溶液同注时,主要发生CH_4水合物的分解,CO_2水合物几乎不生成;(3)当CO_2与浓度为15%的甲醇溶液同注时,既发生CH_4水合物的分解,也发生CO_2水合物的生成;(4)当CO_2与浓度为10%的甲醇溶液同注时,CH_4水合物几乎不分解,主要发生CO_2水合物的生成。结论认为,"抑制剂—置换法"可促进CH_4水合物的分解,提高其开采效率。

关键词：热力学抑制剂二氧化碳同时注入天然气水合物开采置换速率置换程度

甲醇与CO_2/CH_4混合气开采天然气水合物研究

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石油化工高等学校学报 2018年第6期31卷 61-66页

作者：梁萌 Gushchin P.A. Khlebnikov V.n. Antonov S.V. Mishin A.S. Khamidullina I.V. Likhacheva n.V. semenov A.P. Vinokurov V.A. 俄罗斯古勃金国立石油天然气大学化学工程与环境学院

针对CO_2置换法开采CH_4水合物的过程中CO_2水合物在井底过早生成、高压下CO_2发生液化导致渗流过程驱替阻力过大等问题,同时为了获得高压且富含CH_4的产物气,选择CO_2/CH_4混合物作注入气,在岩芯驱替装置上研究了"抑制剂-气体置换法"分... 详细信息

针对CO_2置换法开采CH_4水合物的过程中CO_2水合物在井底过早生成、高压下CO_2发生液化导致渗流过程驱替阻力过大等问题,同时为了获得高压且富含CH_4的产物气,选择CO_2/CH_4混合物作注入气,在岩芯驱替装置上研究了"抑制剂-气体置换法"分解CH_4水合物的过程。结果表明,当混合气中CH_4体积分数为57.4%时,可在7.5 MPa下获得体积分数为72.9%的CH_4产物气,并且获得的CH_4产物气的量要显著大于所注入的CH_4的量。另外,还评估了在地层深部低体积分数的甲醇溶液(20%)和高体积分数CH_4混合气(77.9%)对天然气水合物的分解效果,结果显示,随着"抑制剂-气体置换法"分解天然气水合物过程的进行,地层深部的CH_4水合物基本不发生分解,但CO_2水合物生成过程依然十分显著。

关键词：天然气水合物甲烷水合物非常规天然气二氧化碳热力学抑制剂水合物开采岩芯驱替

Evolution of Stress-Strain State in the Structural Heterogeneities Geomaterials under Uniaxial and Biaxial Loading

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Journal of Applied Mathematics and Physics 2014年第12期2卷 1039-1046页

作者： V. n. Oparin O. M. Usoltseva P. A. Tsoi V. n. semenov Institute of Mining Russian Academy of Sciences Siberian Branch Novosibirsk Russia

The aim of this study was to analyze distribution and development of stress-stress state in structured rock specimens subject to uniaxial and biaxial loading to failure using digital speckle correlation method. Within the experimental analysis of wave processes in the block-hierarchy structure of geomedia (uniaxial and biaxial compression and shearing of prismatic geomaterial specimens), the authors revealed the fact of initiation of low-frequency micro-deformation processes under slow (quasi-static) disturbances. The estimation of the deformation-wave behavior of geomaterials as the “summed” contributions made by elements of the scanned surfaces with different-oriented (in-phase and anti-phase) oscillations has been performed using the energy approach that is based on the scanning function R, analogous to the “center of mass” in the classical mechanics.

关键词： Laboratory Experiment Digital Speckle Correlation Method Rock Mass Hierarchical Block Structure Microstrains Deformation-Wave Processes

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 ...

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

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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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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

生长并且在 WO2/W (110 ) 表面上 C60 分子订被掘的低温度的扫描学习了显微镜学和光谱学，低精力的电子衍射(LEED ) ，和密度(STM 和圣) 功能的理论(DFT ) 计算。结果在分子与一个联合起来的房间参数平等者在形成拥挤不堪的六角形的结构... 详细信息

生长并且在 WO2/W (110 ) 表面上 C60 分子订被掘的低温度的扫描学习了显微镜学和光谱学，低精力的电子衍射(LEED ) ，和密度(STM 和圣) 功能的理论(DFT ) 计算。结果在分子与一个联合起来的房间参数平等者在形成拥挤不堪的六角形的结构到 0.95 nm 的 WO2/W (110 ) 表面上显示秩序井然的 C60 层的生长。C60 层的成核在底层开始内部步边。分子在 78 K 执行了的 C60 的低温度的 STM 在单个分子以内表明解决得好的分子的 orbitals。在 WO2/W (110 ) 表面上的 C60 单层，分子由于分子间的相互作用在一个方向被排列，由单个 C60 的订的分子的 orbitals 出现。在 WO2/W (110 ) 表面上从 C60 单层获得的圣数据在对 DFT 计算的好同意。

关键词： C60分子分子排列表面自组装 DFT计算扫描隧道显微镜分子间相互作用低能电子衍射