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随机扰动下考虑搅油阻力的齿轮动力特性分析

机械传动 2022年第4期46卷 55-62页

作者：刘文宇孙永国于广滨 valerii tupolev 刘伟哈尔滨理工大学机械动力工程学院黑龙江哈尔滨150080 哈尔滨工业大学机电工程学院黑龙江哈尔滨150001 江苏盛安传动股份有限公司江苏盐城224015

搅油润滑是齿轮系统一种重要的润滑方式,由于润滑油的黏弹性会使浸入其中的齿轮在高速运转时获得额外的阻力,且齿轮系统由于自激振动等因素,时刻存在一些不确定的扰动。因此,综合考虑啮合间隙、时变啮合刚度、传动误差、随机扰动以及搅... 详细信息

搅油润滑是齿轮系统一种重要的润滑方式,由于润滑油的黏弹性会使浸入其中的齿轮在高速运转时获得额外的阻力,且齿轮系统由于自激振动等因素,时刻存在一些不确定的扰动。因此,综合考虑啮合间隙、时变啮合刚度、传动误差、随机扰动以及搅油阻力等非线性因素,通过拉格朗日法建立了6自由度的直齿轮非线性动力学模型,运用龙格-库塔方法求解得到系统的分岔图、相图、Poincarè图、时间历程图和动态载荷系数(Dynamic load factor,DLF),综合分析对比了随机扰动下搅油阻力对齿轮系统动态特性的影响。结果表明,随机扰动会使系统的混沌特性发生变化,相图的表现尤为明显,轨迹形状不变,但周期性受到明显影响,周期运动转向准周期运动;在以随机扰动为正常工作状态的条件下,搅油阻力会使得系统提前进入混沌状态。

关键词：非线性随机扰动搅油阻力分岔混沌

Changes in filtration and capacitance properties of highly porous reservoir in underground gas storage:CT-based and geomechanical modeling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2982-2995页

作者： valerii Khimulia Vladimir Karev Yury Kovalenko Svyatoslav Barkov Ishlinsky Institute for Problems in Mechanics RAS Moscow119526Russia

The paper presents the results of comprehensive studies of filtration and capacitance properties of highly porous reservoir rocks of the aquifer of an underground gas storage *** geomechanical part of the research included studying the dependence of rock permeability on the stress-strain state in the vicinity of the wells,and physical modeling of the implementation of the method of increasing the permeability of the wellbore zone-the method of directional unloading of the *** digital part of the research included computed tomography(CT)-based computer analysis of the internal structure,pore space characteristics,and filtration properties before and after the *** to the results of physical modeling of deformation and filtration processes,it is found that the permeability of rocks before fracture depends on the stress-strain state insignificantly,and this influence is ***,when downhole pressure reaches 7-8 MPa,macrocracks in the rock begin to grow,accompanied by irreversible permeability ***,geodesic tortuosity and permeability values were obtained based on digital studies and numerical modeling.A weak degree of transversal anisotropy of the filtration properties of rocks was *** on the analysis of pore size distribution,pressure field and flow velocities,high homogeneity and connectivity of the rock pore space is *** absence of pronounced changes in pore space characteristics and pore permeability after non-uniform triaxial loading rocks was *** the basis of geometrical analysis of pore space,the reasons for weak permeability anisotropy were *** filtration-capacitance properties obtained from the digital analysis showed very good agreement with the results of field and laboratory *** physical modeling has confirmed the efficiency of application of the directional unloading method for the reservoir under *** necessary parameters of its application were calcu

关键词： Permeability anisotropy Reservoir porosity Rocks computed tomography(CT) Digital core analysis Filtration flow numerical modeling

Spark Plasma Sintering of Boron Carbide Using Ti_(3)SiC_(2) as a Sintering Additive

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 645-650页

作者： Hülya Biçer Mustafa Tuncer Hasan Göçmez Iurii Bogomol valerii Kolesnichenko Andrey Ragulya Kutahya Dumlupinar University School of EngineeringDepartment of Metallurgical and Materials EngineeringKütahya 43100Tur-key Boron Based Advanced Ceramics Application and Research Center Kütahya Dumlupınar UniversityKütahya 43100Turkey Advanced Technologies Center(İLTEM) Kütahya Dumlupınar UniversityKütahya 43000Turkey Department of High-Temperature Ma-terials and Powder Metallurgy National Technical University of Ukraine“Igor Sikorsky Kyiv Polytechnic Institute”Kyiv 03056Ukraine Frantsevich Institute for Problems of Materials Science National Academy of Sciences of UkraineKyiv 03056Ukraine

Boron carbide has unique properties for wide application possibilities;however,poor sinterability limits its *** approach to overcome this limitation is the addition of secondary phases into boron *** carbide based composite ceramics are produced by the direct addition of secondary phases into the structure or via reactive sintering using a sintering *** present study investigated the effect of Ti_(3)SiC_(2) addition to boron carbide by reactive spark plasma sintering in the range of 1700-1900℃.Ti_(3)SiC_(2) phase decomposed at high temperatures and reacted with B4C to form secondary phases of TiB2 and *** results demonstrated that the increase of Ti_(3)SiC_(2) addition(up to 15 vol%)effectively promoted the densification of B4C and yielded higher ***,as the amount of Ti_(3)SiC_(2) increased further,the formation of microstructural inhomogeneity and agglomeration of secondary phases caused a decrease in hardness.

关键词： reactive sintering SPS boron carbide MAX phase

Targeting neutrophil subsets is a novel approach for myocardial ischemia-reperfusion injury

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Science Bulletin 2024年第18期69卷 2814-2815页

作者： valerii Chereshnev Institute of Immunology and Physiology Ural Branch of the Russian Academy of ScienceEkaterinburg 620049Russia

Recently,in their 2024 study,Dong et al.[1]revealed the pivotal role of neutrophils in the immune response of myocardial ischemia-reperfusion injury(MIRI)via single-cell RNA sequencing(sc RNA-seq),and identified the existence and function of a novel neutrophil subset with repair phenotype,which participates in the cardio-protection of MIRI by regulating the polarization of macrophages via *** finding not only deepens our understanding of cellular interactions within MIRI but also opens new therapeutic avenues.

关键词： neutrophil ischemia al.

计入齿侧间隙和轴承间隙影响的齿轮-轴-轴承-基础传动系统动态特性研究

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计入齿侧间隙和轴承间隙影响的齿轮-轴-轴承-基础传动系统动态特...

Pareto Optimization as the Basic for Selecting Robotic Mechanic Assembly Technologies

第15届全国转子动力学学术大会（ROTDYN2023）

作者：刘伟李洁钰孙海龙赵强于广滨 valerii tupolev 戴冰

齿轮传动系统中通常含有多种间隙,间隙的存在使系统产生啮合冲击激励及非线性动态特性,加之多间隙间会出现相互耦合作用,严重影响系统动力性能和装备可靠性。本文针对齿轮传动存在的多间隙耦合问题,在轴系单元法基础上提出一种考虑多间... 详细信息

齿轮传动系统中通常含有多种间隙,间隙的存在使系统产生啮合冲击激励及非线性动态特性,加之多间隙间会出现相互耦合作用,严重影响系统动力性能和装备可靠性。本文针对齿轮传动存在的多间隙耦合问题,在轴系单元法基础上提出一种考虑多间隙耦合的齿轮-轴-轴承-基础系统动力学模型,理论推导出含有齿侧间隙、轴承间隙、

关键词：齿侧间隙系统动态特性

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Applied Mathematics 2024年第6期15卷 421-439页

作者： valerii Kyrylovych Dragoljub Tanovic Dmytro Melnychuk Liudmyla Mohelnytska Petro Melnychuk Valery Yanovsky Faculty of Computer-Integrated Technologies Mechatronics and Robotics Zhytomyr Polytechnic State University Zhytomyr Ukraine Faculty of Mechanical Engineering University of Belgrade Belgrade Serbia

The task of selecting robotic mechanic assembly technologies (RMAT) is considered as a multi-criteria optimization task, which in this formulation is solved on the set of previously obtained solutions regarding the selection of RMAT. The purpose of the paper is to increase the efficiency of technological preparation of robotic mechanical assembly production of machine and instrument engineering due to a new approach to the selection of RMAT using Pareto optimization and the peculiarities of the selection task formulation. The novelty consists in the further development of a science-based approach to solving multi-criteria selection task, based on the first proposed formalisms of the specified process, which reflect the peculiarities of the selection task formulation, its meaningful essence and the content of the Pareto optimization method. The practical value of the research lies in the proposed engineering-acceptable approach to solving applied multi-criteria selection tasks on the example of RMAT selection, which is invariant to the statement of the selection task, the dimension of the task, and its meaningful essence. The methods of discrete optimization, fuzzy multi-criteria selection of alternatives, and the Pareto optimization method were used for the research. The main results of this work consist of the development of formalisms and the demonstration of the efficiency of the proposed approach for the applied task of RMAT selection. The peculiarity of the developed approach is the combination of Pareto optimization, performed on a discrete set of local criteria. Directions for further research are presented.

关键词： Multicriteria Optimization Efficiency Fuzzy Multicriteria Selection of Alternatives

Publisher Correction to:Strongly Coupled 2D Transition Metal Chalcogenide‑MXene‑Carbonaceous Nanoribbon Heterostructures with Ultrafast Ion Transport for Boosting Sodium/Potassium Ions Storage

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Nano-Micro Letters 2024年第6期16卷 458-458页

作者： Junming Cao Junzhi Li Dongdong Li Zeyu Yuan Yuming Zhang valerii Shulga Ziqi Sun Wei Han Sino‑Russian International Joint Laboratory for Clean Energy and Energy Conversion Technology International Center of Future ScienceCollege of PhysicsJilin UniversityChangchun 130012People’s Republic of China Centre for Materials Science School of Chemistry and PhysicsQueensland University of Technology(QUT)2 George StreetBrisbaneQLD 4001Australia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071People’s Republic of China

Due to the technical fault,a wrong version of the paper was *** content of the article was not affected,but the layout of the article was *** original article has been corrected.

关键词： Transition Strongly Storage

Generalized Logan’s Problem for Entire Functions of Exponential Type and Optimal Argument in Jackson’s Inequality in L2（R3）

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Acta Mathematica Sinica,English Series 2018年第10期34卷 1563-1577页

作者： valerii IVANOV Alexey IVANOV Department of Applied Mathematics and Computer Science Tula State University

We study Jackson＇s inequality between the best approximation of a function f∈ L2（R^3） by entire functions of exponential spherical type and its generalized modulus of continuity. We prove Jackson＇s inequality with the exact constant and the optimal argument in the modulus of continuity. In particular, Jackson＇s inequality with the optimal parameters is obtained for classical modulus of continuity of order r and Thue-Morse modulus of continuity of order r∈ N. These results are based on the solution of the generalized Logan problem for entire functions of exponential type. For it we construct a new quadrature formulas for entire functions of exponential type.

关键词： Best approximation generalized modulus of continuity Jackson's inequality optimal argument Logan's problem quadrature formula

Nursing education, continuing education and in practice training, research and digital technology application

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International Journal of Nursing Sciences 2017年第4期4卷 343-344页

作者： valerii Samoilenko Russian Nurses Association Russia

***(2015)There are 370 Nursing schools/colleges(+57 Medical Univer-sities)in *** majority of students in Nursing schools/col-leges get education free of charge.

关键词： Nursing education Medical