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Analysis of the discrete contact characteristics based on the Greenwood-Williamson model and the localization principle

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Friction 2024年第5期12卷 1042-1056页

作者： Anastasiya A.YAKOVENKO irina G.GORYACHEVA Ishlinsky Institute for Problems in Mechanics RAS Moscow119526Russia

The contact of a rigid body with nominally flat rough surface and an elastic half-space is considered.To solve the contact problem,the Greenwood-Williamson statistical model and the localization principle are used.The developed contact model allows us to investigate the surface approach and the real contact area with taking into account the asperities interaction.It is shown that the mutual influence of asperities changes not only contact characteristics at the macroscale,but also the contact pressure distribution at the microscale.As follows from the results,the inclusion in the contact model of the effect of the mutual influence of asperities is especially significant for studying the real contact area,as well as the contact characteristics at high applied loads.The results calculated according to the proposed approach are in a good agreement with the experimentally observed effects,i.e.,the real contact area saturation and the additional compliance exhaustion.

关键词： surface roughness elasticity Greenwood-Williamson model localization principle asperity interaction

Infl uence of fire on soil temperatures of pine forests of the middle taiga,central Siberia,Russia

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Journal of Forestry Research 2021年第3期32卷 1139-1145页

作者： irina Nikolaevna Bezkorovaynaya Pavel Albertovich Tarasov irina Gennadievna Gette irina Andreevna Mogilnikova Siberian Federal University 79 SvobodnyKrasnoyarskRussia 660041 Reshetnev Siberian State University of Science and Technology 31 Krasnoyarsky Rabochy AvKrasnoyarskRussia 660037

Temperatures of sandy podzols of middle taiga pine forests with moss and lichen ground cover were analyzed which had been exposed to ground fires of low to medium intensity.In general,temperatures in lichen and moss plots of the pine forests under study,are close to each similar,but in the first year after a fire a noticeable contrast was observed.The reasons are an increase in the amplitude of daily temperatures on the soil surface and stronger heating of upper mineral layers.Temperatures in the mineral layer with depths up to 30 cm depend on the thickness of the forest fl oor.Analysis of the results show that the duration of postfire effects in pine forests with sandy podzols is determined by a number of factors:the intensity of the fire,the degree of erosion of the ground cover and litter,and the recovery rate of these components.

关键词： Ground fire Pine forests Soil temperature

Comparison Analysis of Longitudinal Electrical Conductivity Distribution and Seismic Tomography Velocity Models for the Central Tien Shan Region

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Journal of Earth Science 2023年第2期34卷 580-587页

作者： Olga Zabinyakova Elena Bataleva irina Medved Research Station of the Russian Academy of Sciences in Bishkek City Bishkek 720049Kyrgyzstan Sobolev Institute of Geology and Mineralogy Siberian Branch of the Russian Academy of SciencesNovosibirsk 630090Russia Trofimuk Institute of Petroleum Geology and Geophysics Siberian Branch of the Russian Academy of SciencesNovosibirsk 630090Russia

The paper is dedicated to consider the approach of longitudinal electrical conductivity maps construction for Central Tien Shan region and to complete the comparison analysis of these maps with related seismic tomography data.The results of joint analysis of longitudinal electrical conductivity distribution and seismic tomography velocity models with respect to geological and geophysical senses allow to confirm the already known and to establish the new patterns of structure and geodynamics of the Tien Shan segment of Central Asia such as the manifestation of characteristic structural ensembles,reflection of the longitudinal and transverse segmentation of the Tien Shan,the existence within the framework of a“single”orogen of segments with different near-surface and deep structure and morphological expression.As well,the correlation between the velocity characteristics and geoelectric properties was found.This correlation allows to identify signs of reflection of fault structures in geophysical fields and to clarify the territorial and structural position of both visible and hidden faults.Additionally,in the paper,the geological interpretation of geophysical anomalies is considered.

关键词： profile magnetotelluric soundings longitudinal electrical conductivity map seismic tomography velocity model Tien Shan geophysics

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中国能源投资对俄罗斯经济的影响研究

中国能源投资对俄罗斯经济的影响研究

作者： KAZAK irina 北京交通大学

学位级别：硕士

近十年以来,中国企业对俄罗斯的投资步伐正在不断加紧,投资的领域也比较广泛,但是能源领域是投资的主要行业,加之两国政府的引导,能源领域的投资展现出良好的前景。中国企业在两国政策引导合作的背景下,积极开拓俄罗斯市场,对俄罗斯多... 详细信息

近十年以来,中国企业对俄罗斯的投资步伐正在不断加紧,投资的领域也比较广泛,但是能源领域是投资的主要行业,加之两国政府的引导,能源领域的投资展现出良好的前景。中国企业在两国政策引导合作的背景下,积极开拓俄罗斯市场,对俄罗斯多领域进行直接投资,对俄罗斯社会与经济也产生了深远的影响。因此,基于这一背景下探讨中国企业对俄罗斯能源投资对俄罗斯的经济效应有利于清楚了解投资的影响,对于俄罗斯引资用资的态度及政策制定以及中国企业在俄罗斯的投资深入都有很大的必要性。本文针对中国对俄罗斯能源直接投资对俄罗斯经济发展的影响进行研究,通过对当前中国对俄罗斯能源投资情况所产生的对俄罗斯发展的影响进行定性和定量的研究。在实证分析中利用面板数据和回归模型进行数据处理并最终得出结论:中国企业对俄罗斯能源领域投资导致的劳动力投入的增加以及在固定资产投资上的投入增加。从中国企业对俄罗斯能源领域投资的整体效应来看,当投资增加1%,则可以产生经济增长增加0.905%。中国企业投资俄罗斯能源产业所产生的经济溢出效应被证实,结果显示系数为0.157,这一结果可以解释为如果不受到其他的因素的影响,中国对俄罗斯能源产业的投资造成的经济增长1单位,则能够带动非能源产业的经济贡献增长0.157个单位。简而言之,中国企业投资俄罗斯能源产业除了直接带来的经济效应之外,还能够通过溢出效应带来其他产业的增长,进而对俄罗斯经济产生积极的经济促进效应。本文通过直接投资理论以及经济增长理论进行定性和定量的研究,不仅能够丰富原有研究体系中的研究内容和视角,而且对于进一步发展中俄能源合作的理论政策制定提供指导,也为后面其他学者的深入研究提供思路借鉴。明确外资对俄罗斯经济发展的直接和间接作用能够指导俄罗斯制定相关的外资政策以及对中国企业的投资探明道路,减少“阴谋论”,最终有利于双边投资以及其他的合作关系的进一步密切。

关键词：对外直接投资能源产业经济效应

Optimization of the Dressing Parameters in Cylindrical Grinding Based on a Generalized Utility Function

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 63-73页

作者： ALEKSANDROVA irina Department of Mechanical Engineering Equipment and Technologies Technical University of Gabrovo

The existing studies, concerning the dressing process, focus on the major influence of the dressing conditions on the grinding response variables. However, the choice of the dressing conditions is often made, based on the experience of the qualified staff or using data from reference books. The optimal dressing parameters, which are only valid for the particular methods and dressing and grinding conditions, are also used. The paper presents a methodology for optimization of the dressing parameters in cylindrical grinding. The generalized utility function has been chosen as an optimization parameter. It is a complex indicator determining the economic, dynamic and manufacturing characteristics of the grinding process. The developed methodology is implemented for the dressing of aluminium oxide grinding wheels by using experimental diamond roller dressers with different grit sizes made of medium- and high-strength synthetic diamonds type AC32 and AC80. To solve the optimization problem, a model of the generalized utility function is created which reflects the complex impact of dressing parameters. The model is built based on the results from the conducted complex study and modeling of the grinding wheel lifetime, cutting ability, production rate and cutting forces during grinding. They are closely related to the dressing conditions （dressing speed ratio, radial in-feed of the diamond roller dresser and dress-out time）, the diamond roller dresser grit size/grinding wheel grit size ratio, the type of synthetic diamonds and the direction of dressing. Some dressing parameters are determined for which the generalized utility fimction has a maximum and which guarantee an optimum combination of the following： the lifetime and cutting ability of the abrasive wheels, the tangential cutting force magnitude and the production rate of the grinding process. The results obtained prove the possibility of control and optimization of grinding by selecting particular dressing parameters.

关键词： dressing conditions cylindrical grinding diamond roller dresser generalized utility function based optimization

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新冠疫情下俄罗斯大学生汉语学习动机研究

新冠疫情下俄罗斯大学生汉语学习动机研究

作者： Ivanova irina 浙江科技学院

学位级别：硕士

第二语言学习动机研究始于20世纪下半叶,很快便成为教育研究界的热议话题。然而,长期以来关于第二语言学习动机的研究大多集中在英语学习动机的研究上。近十年来,该领域的学者开始强调研究英语以外语言学习动机的重要性。同时,当今学者... 详细信息

第二语言学习动机研究始于20世纪下半叶,很快便成为教育研究界的热议话题。然而,长期以来关于第二语言学习动机的研究大多集中在英语学习动机的研究上。近十年来,该领域的学者开始强调研究英语以外语言学习动机的重要性。同时,当今学者们面临的一大新问题是社会、政治、经济等因素如何影响学生学习外语的动机。基于这两大趋势,本文将针对俄罗斯大学生在新冠疫情背景下学习汉语的动机展开深入研究。首先,文献综述追溯了第二语言学习动机研究的历史,并围绕汉语学习动机研究和俄罗斯学习者汉语学习动机研究进行了述评。然后,为了探究俄罗斯大学生在新冠疫情下的汉语学习动机,笔者收集了100份俄罗斯大学生的调查问卷,根据学生的性别和年龄对数据进行了分析,并借助与新冠疫情相关的一些假设阐释了新冠疫情对俄罗斯大学生学习汉语的动机可能产生的影响。根据调查结果得出了以下结论:1)在新冠疫情下俄罗斯大学生学习汉语的动机很强。数据分析显示,目前俄罗斯大学生的融入型动机比工具型动机更为强烈;2)不同性别人群总动机之间不存在显著差异性;3)不同年龄段的俄罗斯大学生学习汉语的动机存在明显差异,即学习外语的动机随着年龄的增长而下降;4)新冠疫情对俄罗斯大学生学习汉语的兴趣和动机的影响非常明显,这种影响具有个体化表征。最后,根据得出的结论,从学生层面、教师层面和学校管理层面出发,提出相应的激发和维持俄罗斯大学生学习汉语动机的对策。希望本研究的结果不仅能够引起学者对俄罗斯学生汉语学习动机现状的关注,同时为未来研究社会、政治、经济和语言现象等因素对第二语言学习动机影响提供参考。

关键词：汉语学习动机新冠疫情俄罗斯大学生问卷调查

Changes in renal function and morphological variations of kidney diseases in rheumatoid arthritis patients

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Asian Journal of Urology 2024年第2期11卷 304-310页

作者： Yan Tang Yuliya Varavko Raisa Aringazina irina Menshikova College of Medical Technology Yongzhou Vocational Technical CollegeYongzhouChina Department of Internal Diseases Propaedeutics Irkutsk State Medical UniversityIrkutskRussian Federation Department of Internal Diseases No.1 Non-Commercial Joint-Stock Society“West Kazakhstan Marat Ospanov Medical University”AktobeKazakhstan Department of Hospital Therapy No.1 I.M.Sechenov First Moscow State Medical University of Ministry of Health of Russian Federation(Sechenov University)MoscowRussian Federation

Objective:Rheumatoid nephropathy is one of the most severe extra-articular manifestations of rheumatoid arthritis(RA)associated with a very unfavorable prognosis.This study aimed to identify changes in renal function and morphological variations of kidney diseases in RA patients.Methods:The study enrolled patients(126 patients)between 18 and 55 years of age with a confirmed active RA of more than 12 months.Each patient underwent the following range of laboratory and instrumental research methods:general clinical analysis of blood and urine,performing urinalysis according to Nechiporenko method;determining daily proteinuria;determining the blood content of glucose,urea,creatinine,uric acid,total bilirubin,liver transaminase level,ionogram,lipidogram,and coagulogram;determining the blood content of rheumatoid factor,anti-streptolysin O,and C-reactive protein;and X-ray of the joints of hands and feet.Renal function was examined by estimating glomerular filtration rate,tubular reabsorption index,and renal functional reserve.For studying the morphological changes in the kidneys under ultrasound examination,renal biopsy was performed in 31 patients with RA with urinary syndrome(proteinuria more than 0.3 g per day and hematuria).Results:Nephropathy in RA is characterized by impaired renal function and manifested by an increased blood creatinine and a decrease in glomerular filtration rate and renal functional reserve.Among morphological variations of nephropathy at RA,mesangial proliferative glomerulonephritis prevails,accounting for 48.4%of patients.Other disorders include the secondary amyloidosis(29.0%of patients),tubulointerstitial nephritis(16.1%),membranous glomerulonephritis(3.2%),and focal-segmental glomerulosclerosis(3.2%).Conclusion:Kidney damage is a common systemic manifestation of RA with a long and active course,a major nephropathy trigger.

关键词： Rheumatoid nephropathy Secondaryrenal amyloidosis Mesangial proliferative glomerulonephritis Renal functional reserve

Physiological and biochemical characteristic of Miscanthus×giganteus grown in heavy metal-oil sludge co-contaminated soil

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Journal of Environmental Sciences 2022年第5期34卷 114-125页

作者： Anna Muratova Yelena Lyubun irina Sungurtseva Olga Turkovskaya Asil Nurzhanova Institute of Biochemistry and Physiology of Plants and Microorganisms RAS Saratov 410015Russia Institute of Plant Biology and Biotechnology Almaty 050040Kazakhstan

The effect of oil sludge and zinc,present in soil both separately and as a mixture on the physiological and biochemical parameters of Miscanthus×giganteus plant was examined in a pot experiment.The opposite effect of pollutants on the accumulation of plant biomass was established:in comparison with uncontaminated control the oil sludge increased,and Zn reduced the root and shoot biomass.Oil sludge had an inhibitory effect on the plant photosynthetic apparatus,which intensified in the presence of Zn.The specific antioxidant response of M.×giganteus to the presence of both pollutants was a marked increase in the activity of superoxide dismutase(mostly owing to oil sludge)and glutathione-S-transferase(mostly owing to zinc)in the shoots.The participation of glutathione-S-transferase in the detoxification of both the organic and the inorganic pollutants was assumed.Zn inhibited the activity of laccase-like oxidase,whereas oil sludge promoted laccase and ascorbate oxi-dase activities.This finding suggests that these enzymes play a part in the oxidative detox-ification of the organic pollutant.With both pollutants used jointly,Zn accumulation in the roots increased 6-fold,leading to increase in the efficiency of soil clean-up from the metal.In turn,Zn did not significantly affect the soil clean-up from oil sludge.This study shows for the first time the effect of co-contamination of soil with oil sludge and Zn on the phys-iological and biochemical characteristics of the bioenergetic plant M.×giganteus.The data obtained are important for understanding the mechanisms of phytoremediation with this plant.

关键词： Miscanthus×giganteus Oil sludge Zinc Antioxidant enzymes Oxidative enzymes

Role of intergenic interactions among folate cycle genes in the development of fetal growth retardation

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Reproductive and Developmental Medicine 2023年第1期7卷 32-37页

作者： Olesya Efremova irina Ponomarenko Mikhail Churnosov Department of Biomedical Disciplines Belgorod State University308015 BelgorodRussia

Objective:Metabolic disturbances in the folate cycle in mothers can lead to fetal growth retardation(FGR).This study was to analyze the role of intergenic interactions among maternal folate cycle genes in the development of FGR.Methods:This case-control study recruited 365 women in the third trimester of pregnancy,including 122 FGR patients and 243 controls.The women were genotyped for 5 polymorphisms of the 4 folate cycle genes:MTR(rs1805087),MTRR(rs1801394),serine hydroxymethyl transferase(SHMT1;rs1979277),and TYMS(rs699517 and rs2790).The SNP×SNP interactions in the two-,three-,and four-locus models were analyzed using the multifactor dimensionality reduction method and a modification of it(the model-based multifactor dimensionality reduction method).Results:Four loci of maternal folate cycle genes(rs1805087 MTR,rs2790 TYMS,rs1801394 MTRR,and rs1979277 SHMT1)were associated with FGR in 3 significant models of single nucleotide polymorphism(SNP)×SNP interactions(two-,three-,and four-locus models)(P<0.05).The highest contribution to FGR was made by polymorphic loci rs1979277 SHMT1(1.70%of entropy),rs1805087 MTR(0.96%),and interactions between rs1979277 SHMT1×rs1805087 MTR(-1.11%)and rs1801394 MTRR×rs1979277 SHMT1(-0.64%).The four-locus maternal genotype combination AG rs1801394 MTRR×AA rs1805087 MTR×CT rs1979277 SHMT1×AG rs2790 TYMS was associated with an increased risk of FGR(β=2.69,P=0.012).FGR-associated SNPs were correlated with the expression of 16 genes(MTR,MTRR,SHMT1,ALKBH5,CTD-2303H24.2,ENOSF1,FAM106A,FOXO3B,LGALS9C,LLGL1,MIEF2,NOS2P2,RP11-806L2.6,SMCR8,TOP3A,and USP32P2)in various tissues and organs related to FGR pathophysiology.Conclusion:SNP×SNP interactions of maternal folate cycle genes(MTR,MTRR,SHMT1,and TYMS)are associated with the development of FGR.

关键词： Polymorphism Associations Fetal growth retardation Folate SNP×SNP interactions