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雅库特铁路路堤富冰冻土的温度研究(英文)

黑龙江大学工程学报 2014年第3期5卷 90-99页

作者： stepan varlamov 俄罗斯科学院西伯利亚分院麦尔尼科夫冻土研究所

由Tommot到Niznhy Bestyakh铁路建设和运行的主要难题是横贯高含冰量冻土区域。自2007年以来,监测研究已经由麦尔尼科夫冻土研究所在该铁路试验段进行。其中一个监测计划的主要目标是评估不同设计的堤防地面热状况。观测巷道中使用高、... 详细信息

由Tommot到Niznhy Bestyakh铁路建设和运行的主要难题是横贯高含冰量冻土区域。自2007年以来,监测研究已经由麦尔尼科夫冻土研究所在该铁路试验段进行。其中一个监测计划的主要目标是评估不同设计的堤防地面热状况。观测巷道中使用高、低和零堤防热管及保温绝缘材料。实地研究表明,每年高路堤的散热效果要小于低路堤。阴影边坡下方的土壤趋于低温,而更多的边坡下方的多年冻土上限是由于地表水的增温效应降低所导致。冬季冻土路堤材料导致其冻胀,其上升的速度使其形成更高的堤防。夏季,零堤的位置处于切除活跃层会导致常年解冻区域的发展,有着较厚的填充和更深层次季节性融化。热虹吸和绝缘材料使得上坡护堤和下坡护堤产生轻微冷却效果。悬雪棚并未证明可以有效地降低地面温度。建议采取额外措施,以降低地面温度,减少巷道的季节性融化。

关键词：巷道高含冰量冻土层地温效应热虹吸绝缘

Methodology for local correction of the heights of global geoid models to improve the accuracy of GNSS leveling

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Geodesy and Geodynamics 2024年第1期15卷 42-49页

作者： stepan Savchuk Alina Fedorchuk Institute of Navigation Military University of AviationDeblinPoland Department of Higher Geodesy and Astronomy Lviv Polytechnic National UniversityLvivUkraine

At present,one of the methods used to determine the height of points on the Earth’s surface is Global Navigation Satellite System(GNSS)*** is possible to determine the orthometric or normal height by this method only if there is a geoid or quasi-geoid height model *** paper proposes the methodology for local correction of the heights of high-order global geoid models such as EGM08,EIGEN-6C4,GECO,and XGM2019e_*** methodology was tested in different areas of the research field,covering various relief *** dependence of the change in corrected height accuracy on the input data was analyzed,and the correction was also conducted for model heights in three tidal systems:"tide free","mean tide",and"zero tide".The results show that the heights of EIGEN-6C4 model can be corrected with an accuracy of up to 1 cm for flat and foothill terrains with the dimensionality of 1°×1°,2°×2°,and 3°×3°.The EGM08 model presents an almost identical *** EIGEN-6C4 model is best suited for mountainous relief and provides an accuracy of 1.5 cm on the 1°×1°*** height correction accuracy of GECO and XGM2019e_2159 models is slightly poor,which has fuzziness in terms of numerical fluctuation.

关键词： GNSS leveling Global geoid model Gravity anomaly Weight data Correcting data

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多年冻土区表层土壤冻融的季节动态(英文)

黑龙江大学工程学报 2014年第3期5卷 202-205,214页

作者： Peter Permyakov Georgy Popov stepan varlamov 俄罗斯科学院西伯利亚分院北极物理技术研究所俄罗斯科学院西伯利亚分院麦尔尼科夫冻土研究所

建立了考虑地基孔隙溶液迁移因素影响的冻胀计算数学模型。提出了管道下方土壤季节性冻融的数值试验结果。

关键词：冻土季节性冻融数学模型

当前气候变化下的雅库特中部地区土壤温度状况预测(英文)

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黑龙江大学工程学报 2014年第3期5卷 8-12页

作者： Peter Permyakov stepan varlamov Pavel Skryabin Yara Ckachkov 俄罗斯科学院西伯利亚分院北极自然技术研究所俄罗斯科学院西伯利亚分院麦尔尼科夫冻土研究所

预测土壤温度采用通用的年平均气象数据中的空气温度和积雪深度。为改善冻土的预测可靠性,将每月的气象数据考虑在计算方法中。

关键词：冻土数学模型数值计算结果现场实测对比

High performance Wannier interpolation of Berry curvature and related quantities with WannierBerri code

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npj Computational Materials 2021年第1期7卷 293-301页

作者： stepan S.Tsirkin Department of Physics University of ZurichWinterthurerstrasse 190Zurich CH-8057Switzerland

Wannier interpolation is a powerful tool for performing Brillouin zone integrals over dense grids of k points,which are essential to evaluate such quantities as the intrinsic anomalous Hall conductivity or Boltzmann transport ***,more complex physical problems and materials create harder numerical challenges,and computations with the existing codes become very expensive,which often prevents reaching the desired *** this article,I present a series of methods that boost the speed of Wannier interpolation by several orders of *** include a combination of fast and slow Fourier transforms,explicit use of symmetries,and recursive adaptive grid refinement among *** proposed methodology has been implemented in the python code WannierBerri,which also aims to serve as a convenient platform for the future development of interpolation schemes for other phenomena.

关键词： interpolation quantities Wannier

HOMOCLINIC SOLUTIONS OF NONLINEAR LAPLACIAN DIFFERENCE EQUATIONS WITHOUT AMBROSETTI-RABINOWITZ CONDITION

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Acta Mathematica Scientia 2021年第3期41卷 712-718页

作者： Antonella NASTASI stepan TERSIAN Calogero VETRO University of Palermo Department of Mathematics and Computer ScienceVia Archirafi 3490123PalermoItaly Institute of Mathematics and Informatics Bulgarian Academy of Sciences1113 SofiaBulgaria

The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mo... 详细信息

关键词： Difference equations homoclinic solutions non-zero solutions (p,q)-Laplacian operator

ON THE FOURIER-VILENKIN COEFFICIENTS

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Acta Mathematica Scientia 2017年第2期37卷 293-300页

作者： Martin G.GRIGORYAN stepan SARGSYAN Chair of Higher Mathematics Faculty of Physics Yerevan State University

In this article, we prove the following statement that is true for both unbounded and bounded Vilenkin systems： for any ε∈ （0, 1）, there exists a measurable set E C [0, 1） of measure bigger than 1 - s such that for any function f ∈ LI[0, 1）, it is possible to find a function g ∈ L^1 [0, 1） coinciding with f on E and the absolute values of non zero Fourier coefficients of g with respect to the Vilenkin system are monotonically decreasing.

关键词： Vilenkin system expansions Fourier coefficients

Impact of drilling waste pollution on land cover in a high subarctic forest-tundra zone

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Pedosphere 2022年第3期32卷 414-425页

作者： Anatoly OPEKUNOV Marina OPEKUNOVA stepan KUKUSHKIN Sergey LISENKOV Institute of Earth Sciences St.Petersburg State UniversitySt.Petersburg 199178(Russia)

Global climate changes can lead to the destruction of the permafrost zone and contribute to the active transfer of pollutants to natural *** can be especially pronounced in the areas of oil and gas production in the *** study aimed to define the landscape components(i.e.,groundwater,soil water,soil,and indicator plant species)of chemical pollution with metals,oil hydrocarbons,and polycyclic aromatic hydrocarbons,from the discharge of drill *** at two sites in the forest-tundra zone of Western Siberia(Russia)were carried out within two years of *** migration was found in peaty-gley heavy loamy soils and iron-illuvial clayey podburs,but lateral migration of different pollutants did not exceed 200 ***,radial migration was practically absent owing to the high buffering capacity of the soil organic horizon and the upward flow of matter in the seasonal melt *** main indicators of drilling waste pollution were high concentrations of Sr,Ba,petroleum hydrocarbons,and Cl^(-)*** the waste disposal sites,the concentration of Ba and Sr in the soil water were 1150 and 1410μg L^(-1),respectively;in groundwater,they reached 721 and 2360μg L^(-1),*** the soil,Ba and Sr accumulated in the peaty horizon(798 and 706 mg kg^(-1),respectively).The concentration of Cl^(-)ions in the soil water at the site of waste discharge was 1912 mg L^(-1),and at a distance of 200 m,it decreased to 77.4 mg L^(-1).The Cl^(-)concentration in the groundwater was lower,and at a distance of 200 m,it was 38.9 mg L^(-1).The highest concentration of petroleum hydrocarbons in the surface layer was found in the peaty-gley soils(up to 2400 mg kg^(-1)).In glandular-illuvial podburs,it was 420 mg kg^(-1).In horizons BH and BC,it was close to the background values(27 and 33 mg kg^(-1),respectively).Alkalinization of soils and water under the influence of drill cuttings led to the death of oligotrophic and acidophilic vegetation at a distanc

关键词： metal petroleum hydrocarbons plant indicator species pollutant migration in soil polycyclic aromatic hydrocarbon

Thermal radiation and natural convection in a large-scale enclosure heated from below:Building application

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Building Simulation 2021年第3期14卷 681-691页

作者： stepan A.Mikhailenko Igor V.Miroshnichenko Mikhail A.Sheremet Laboratory on Convective Heat and Mass Transfer Tomsk State University634050 TomskRussia Regional Scientific and Educational Mathematical Centre Tomsk State University634050 TomskRussia

A computational research of radiative-convective energy transport in large-scale enclosure with a heat-generating heater under normal room conditions has been *** heater(underfloor heating system)is located at the bottom of the *** the Boussinesq assumption,the control equations have been solved contemporaneously to receive both the velocity fields and temperature *** generate the systems of linear equations using vorticity and stream function,the finite difference technique has been *** developed convective-radiative model has been validated through a comparison with several *** influence of heater size and location,internal surfaces emissivity from 0 to 1,Ostrogradsky number for a wide range from 0 to 5 on Nusselt numbers and both stream function and temperature distributions has been *** results demonstrate that the influence of the thermal radiation on total heat transfer increases with surface emissivity of walls and heater surfaces.

关键词： indoor environment natural convection thermal radiation large-scale cabinet local heater finite difference method