检索结果-南通市图书馆

Nonlinear Young’s Modulus of New Red Sandstone:Experimental Studies

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2021年第6期34卷 989-999页

作者： Evgenii Riabokon Vladimir Poplygin mikhail Turbakov Evgenii Kozhevnikov Dmitrii Kobiakov mikhail guzev Marian Wiercigroch Centre for Applied Dynamics Research School of EngineeringUniversity of AberdeenAberdeenUK Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPermRussia Institute of Applied Mathematics Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia

Young’s modulus of New Red Sandstone was investigated experimentally to gain insight into its nonlinear nature.A large experimental programme was carried out by applying a controllable quasi-static and dynamic uniaxial loading to 286 dry sandstone samples of four different *** static and dynamic tests,similar to those aiming at determining the uniaxial compressive strength,were conducted using the state-of-the-art experimental facilities at the University of Aberdeen including a custom-built small experimental rig for inducing a dynamic uniaxial compressive load via a piezoelectric *** obtained results have confirmed a complex nature of Young’s modulus of ***,under a harmonic dynamic loading,it shows strongly nonlinear behaviour,which is hardening and softening with respect to frequency and amplitude of the dynamic loading,respectively.

关键词： Sandstone Young’s modulus Static and dynamic loading Experiments Stress and strain Nonlinearity

Assessment of the Elastic-Wave Well Treatment in Oil-Bearing Clastic and Carbonate Reservoirs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2023年第6期19卷 1495-1505页

作者： Vladimir Poplygin Chengzhi Qi mikhail guzev Evgenii Kozhevnikov Artem Kunitskikh Evgenii Riabokon mikhail Turbakov Perm National Research Polytechnic University Perm614990Russian Beijing University of Civil Engineering and Architecture Beijing100049China Institute for Applied Mathematics FEB RAS Vladivostok690041Russian

A set of techniques for well treatment aimed to enhance oil recovery are considered in the present *** are based on the application of elastic waves of various types(dilation-wave,vibro-wave,or other acoustically induced effects).In such a context,a new technique is proposed to predict the effectiveness of the elastic-wave well treatment using the rank distribution according to Zipf’s *** is revealed that,when the results of elastic wave well treatments are analyzed,groups of wells exploiting various geological deposits can differ in terms of their slope coefficients and free *** the slope coefficient increases,the average increase in the well oil production rate(after the well treatment)becomes *** equation is obtained accordingly for estimating the slope coefficient in the Zipf’s equation from the frequency of the elastic *** obtained results demonstrate the applicability of the Zipf’s law in the analysis of the technological efficiency of elastic-wave well treatment methods.

关键词： Elastic wave well treatment oil well rate Zipf’s law rank distribution slope coefficient

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

厚壁筒的一种简化弹性应变梯度模型

解放军理工大学学报（自然科学版） 2014年第1期15卷 30-37页

作者：李凯锐戚承志 guzev mikhail 北京建筑大学北京市高校工程结构与新材料工程研究中心北京100044 俄罗斯科学院远东分院应用数学研究所

在Toupin-Mindlin应变梯度理论框架内,建立了一种关于厚壁筒的应变梯度模型,并利用打靶法和拟牛顿迭代法实现了两点复杂边界条件和四阶常微分平衡方程的求解,得到了厚壁筒应力场和位移场精确数值解。为了降低该模型的复杂性和提高该模... 详细信息

在Toupin-Mindlin应变梯度理论框架内,建立了一种关于厚壁筒的应变梯度模型,并利用打靶法和拟牛顿迭代法实现了两点复杂边界条件和四阶常微分平衡方程的求解,得到了厚壁筒应力场和位移场精确数值解。为了降低该模型的复杂性和提高该模型的适用性,通过对高阶应力做出简化假设,得到了简化的平衡方程和相应的厚壁筒应力、应变的解析解。通过对厚壁筒经典弹性理论解析解、梯度理论简化解和梯度理论精确数值解的比较,检验了简化模型解析解的可行性和精确性,并得到了梯度理论和经典理论在厚壁筒应用上的差异性。

关键词：应变梯度理论厚壁筒高阶应力简化模型解析解

Corrigendum to “Non-classical solutions of a continuum model for rock descriptions” [J Rock Mech Geotech Eng 6(3)(2014) 180e185]

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 358-358页

作者： mikhail A.guzev Institute for Applied Mathematics Far Eastern Branch of the Russian Academy of Sciences

The author regrets that the acknowledgement section was inadvertently missed out in the published *** Acknowledgement is given below:The author is grateful to the academician Qihu Qian for constructive *** paper was supported by grant numbers No.13-06-011 3m-a from the"Scientific Fund"of Far Eastern Federal University and the Ministry of Education and Science of the Russian Federation Grant No.5.2535.2014K.

关键词： Corrigendum to J Rock Mech Geotech Eng 6 Non-classical solutions of a continuum model for rock descriptions

An application of space-filling curves to improve results of turbulent aerodynamics modeling with convolutional neural networks

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第2期37卷 81-92页

作者： mikhail PETROV Sofia ZIMINA Moscow Institute of Physics&Technology Dolgoprudny 141701Russia

When carrying out calculations for turbulent flow simulation,one inevitably has to face the choice between accuracy and speed of *** order to simultaneously obtain both a computationally efficient and more accurate model,a surrogate model can be built on the basis of some fast special model and knowledge of previous calculations obtained by more accurate base models from various test bases or some results of serial *** objective of this work is to construct a surrogate model which allows to improve the accuracy of turbulent calculations obtained by a special model on unstructured *** this purpose,we use 1D Convolutional Neural Network(CNN)of the encoder-decoder architecture and reduce the problem to a single dimension by applying space-filling *** an approach would have the benefit of being applicable to solutions obtained on unstructured *** this work,a non-local approach is applied where entire flow fields obtained by the special and base models are used as input and ground truth output ***-Allmaras(SA)model and Near-wall Domain Decomposition(NDD)method for SA are taken as the base and special models *** efficiency and accuracy of the obtained surrogate model are demonstrated in a case of supersonic flow over a compression corner with different values for angleαand Reynolds number *** conducted an investigation into interpolation and extrapolation by Re and also into interpolation byα.

关键词： Space-filling curves Convolutional neural network Domain decomposition Turbulent flows Unstructured mesh

The current status and future development of high-temperature conventional superconductivity

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第7期11卷 18-20页

作者： mikhail I.Eremets High Pressure Chemistry and Physics Group Max-Planck-Institut für Chemie

This survey highlights key advancements in high-temperature superconductivity in hydrogen-rich materials, emphasizing the robust evidence and reproducibility of superconductivity under challenging experimental conditions of megabar pressures. In the near future, achieving room-temperature superconductivity is highly probable, and the field is expected to transition towards near-ambient-pressure superconductivity.

关键词：

Pricing Binary Variables of System-wide Constraints for Power System Optimization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第3期10卷 1131-1144页

作者： Jiaxun Li Wei Lin Zhifang Yang mikhail Davidson State Key Laboratory of Power Transmission Equipment and System Security and New Technology College of Electrical EngineeringChongqing UniversityChongqing 400030China Department of Electrical Engineering The Hong Kong Polytechnic UniversityHong Kong SAR 999077China Faculty of Computational Mathematics and Cybernetics Moscow State UniversityMoscow 119991Russia IEEE

With the trend of multiple energies or flexible demand in power systems,binary variables appear in systemwide constraints,which are the foundation of marginal pricing currently in *** appropriate pricing method incentivizes compliance of market participants;otherwise,compliance can be incentivized by paying discriminatory uplift payments which jeopardize transparency of *** paper proposes two theorems to examine whether the binary variables brought by multiple energies and flexible demand will impact compliance under marginal *** first theorem shows sufficient conditions with which marginal pricing with fixed binary variables incentivizes compliance,while the second theorem shows sufficient conditions to require uplift *** improve transparency by reducing uplift payments under cases which fall into the second theorem,this paper further proposes a pricing method by combining 1)designed constraints to price binary variables in system-wide constraints,and 2)convex hull pricing to price binary variables in private *** of the proposed theorems and pricing method is verified in an electricity-gas case(consisting of the IEEE 30-bus system and the NGS 10-node system)and the IEEE 118-bus test system.

关键词： Binary variables impact analysis pricing under non-convexities

A critical review on solid-state welding of high entropy alloys-processing,microstructural characteristics and mechanical properties of joints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第4期34卷 78-133页

作者： Tushar Sonar mikhail Ivanov Evgeny Trofimov Aleksandr Tingaev Ilsiya Suleymanova Department of Welding Engineering Institution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia Department of Materials Science Physical and Chemical Properties of MaterialsInstitution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia

The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion *** alloys are manufactured by the equal mixing or larger proportions of five or more alloying *** exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of *** state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA *** HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs *** similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial ***,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNiMn and Al_xCoCrFeNi *** state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints.

关键词： High entropy alloys Solid state welding Microstructure Mechanical properties

A rened analytical model for reconstruction problems in diuse reectance spectroscopy

在线全文

学校读者我要写书评

暂无评论

Journal of Innovative Optical Health Sciences 2024年第5期17卷 33-51页

作者： Ekaterina Sergeeva Daria Kurakina Ilya Turchin and mikhail Kirillin A.V.gaponov-grekhov institute of applied physics of the russian academy of sciences ulyanov st.46 603950nizhny novgorodrussia

A rened analytical model of spatially resolved diffuse reectance with small source-detector separations(SDSs)for the in vivo skin studies is *** to the conventional model developed by Farrell et al.,it accounts for the limited acceptance angle of the *** rened model is validated in the wide range of optical parameters by Monte Carlo simulations of skin diffuse reectance at SDSs of units of *** of uniform dermis and two-layered epidermis-dermis structures are *** accuracy of the rened model compared to the conventional one is demonstrated in the separate,constraint-free reconstruction of absorption and reduced scattering spectra of uniform dermis from the Monte Carlo simulated *** the case of epidermis-dermis geometry,the recovered values of reduced scattering in dermis are overestimated and the recovered values of absorption are underestimated for both analytical ***,in the presence of a thin mismatched topical layer,only the effective attenuation coe±cient of the bottom layer can be accurately recovered using a diffusion theorybased analytical model while separate reconstruction of absorption and reduced scattering fails due to the inapplicability of the method of ***-ndings require implementation of more sophisticated models of light transfer in inhomogeneous media in the recovery algorithms.

关键词： Diffuse reffectance spectroscopy in vivo skin studies optical properties reconstruction diffuse approximation Monte Carlo simulations method of images