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The experience of land cover change detection by satellite data

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Frontiers of Earth Science 2012年第2期6卷 140-146页

作者： Lev SPIVAK Irina VITKOVSKAYA Madina BATYRBAYEVA alexey TEREKHOV The Institute of Space Research National Centre of Space Research and Technology of the Republic of Kazakhstan Almaty 050010 Kazakhstan

Sigificant dependence from climate and anthropogenic influences characterize ecological systems of Kazakhstan. As result of the geographical location of the republic and ecological situation vegetative degradation sites exist throughout the territory of Kazakhstan. The major process of desertification takes place in the arid and semi-arid areas. To allocate spots of stable degradation of vegetation, the transition zone was first identified. Productivity of vegetation in transfer zone is slightly dependent on climate conditions. Multi-year digital maps of vegetation index were generated with NOAA satellite images. According to the result, the territory of the republic was zoned by means of vegetation productivity criterion. All the arable lands in Kazakhstan are in the risky agriculture zone. Estimation of the productivity of agricultural lands is highly important in the context of risky agriculture, where natural factors, such as wind and water erosion, can significantly change land quality in a relatively short time period. We used an integrated vegetation index to indicate land degradation measures to assess the inter-annual features in the response of vegetation to variations in climate conditions from low- resolution satellite data for all of Kazakhstan. This analysis allowed a better understanding of the spatial and temporal variations of land degradation in the country.

关键词： remote sensing NOAA land cover changes,vegetation indexes

Control of combustion area using electrical resistivity method for underground coal gasification

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International Journal of Mining Science and Technology 2012年第3期22卷 351-355页

作者： Selivanova Tatiana Grebenyuk Igor Belov alexey Engineering School Far Eastern Federal University Vladivostok Russian Federation

Underground coal gasification （UCG） is one of the clean technologies to collect heat energy and gases （hydrogen, methane, etc.） in an underground coal seam. It is necessary to further developing environ- mentally friendly UCG system construction. One of the most important UCG＇s problems is underground control of combustion area for efficient gas production, estimation of subsidence and gas leakage to the surface. For this objective, laboratory experiments were conducted according to the UCG model to iden- ti[y the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area. While burning coal specimens, that had been sampled from various coal deposits, electrical resistivity was monitored. Symmetric four electrodes system （ABMN） of direct and low-frequency current electric resistance method was used for laboratory resistivity measurement of rock samples. Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature. Combusting coal electro conductivity has compli- cated multistage type of change. Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam.

关键词： Underground coal gasificationMonitoringElectro conductivityLaboratory experimentCoal specimen

Traditional taxonomy: Quo vadis?

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Integrative Zoology 2016年第6期11卷 500-505页

作者： alexey A.KOTOV Maria A.GOLOLOBOVA Laboratory of Aquatic Ecology and Invasions A.N.Severtsov Institute of Ecology and EvolutionMoscowRussia Laboratory for Palaeoclimatology Palaeoecology and PalaeomagnetismKazan Federal UniversityKazanRussia Faculty of Biology M.V.Lomonosov Moscow State UniversityMoscowRussia

TRADITIONAL TAXONOMY “Taxonomy is the science of naming,describing and classifying organisms and includes all plants,animals and microorganisms of the world”(Convention on Biological Diversity 2016).It is obvious that progress in biological science is impossible without taxonomic ef*** the last 250 years,taxonomists have named almost two million species of animals,plants and mi*** recently taxonomy has entered a deep crisis(Agnarson&Kuntner 2007;Walter&Winterton 2007);in particular,this crisis involves the science of traditional taxonomy.

关键词： taxonomy Taxonomy Diversity

Effects of subsampling on characteristics of RNA-seq data from triple-negative breast cancer patients

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Chinese Journal of Cancer 2015年第10期34卷 427-438页

作者： alexey Stupnikov Galina V Glazko Frank Emmert-Streib Computational Biology and Machine Learning Laboratory Faculty of MedicineHealth and Life SciencesSchool of MedicineDentistry and Biomedical SciencesCenter for Cancer Research and Cell BiologyQueen's University Belfast Division of Biomedical Informatics University of Arkansas for Medical Sciences Computational Medicine and Statistical Learning Laboratory Department of Signal ProcessingTampere University of Technology

Background:Data from RNA-seq experiments provide a wealth of information about the transcriptome of an ***,the analysis of such data is very *** this study,we aimed to establish robust analysis procedures that can be used in clinical ***:We studied RNA-seq data from triple-negative breast cancer ***,we investigated the subsampling of RNA-seq ***:The main results of our investigations are as follows:(1) the subsampling of RNA-seq data gave biologically realistic simulations of sequencing experiments with smaller sequencing depth but not direct scaling of count matrices;(2) the saturation of results required an average sequencing depth larger than 32 million reads and an individual sequencing depth larger than 46 million reads;and(3) for an abrogated feature selection,higher moments of the distribution of all expressed genes had a higher sensitivity for signal detection than the corresponding mean ***:Our results reveal important characteristics of RNA-seq data that must be understood before one can apply such an approach to translational medicine.

关键词： RNA-seq data, Computational genomics, Statistical robustness, High-dimensional biology,Triple-negative breast cancer

DIRECT MINIMIZATION FOR CALCULATING INVARIANT SUBSPACES IN DENSITY FUNCTIONAL COMPUTATIONS OF THE ELECTRONIC STRUCTURE

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Journal of Computational Mathematics 2009年第2期27卷 360-387页

作者： Reinhold Schneider Thorsten Rohwedder alexey Neelov Johannes Blauert Institute for Mathematics Technical University BerlinStraβe des 17.Juni 13510623 BerlinGermany Institute of Physics University of BaselKlingelbergstrasse 824056 BaselSwitzerland Institute for Mathematics Technical University BerlinStraβe des 17. Juni 13510623 BerlinGermany

In this article, we analyse three related preconditioned steepest descent algorithms, which are partially popular in Hartree-Fock and Kohn-Sham theory as well as invariant subspace computations, from the viewpoint of minimization of the corresponding functionals, constrained by orthogonality conditions. We exploit the geometry of the admissible manifold, i.e., the invariance with respect to unitary transformations, to reformulate the problem on the Grassmann manifold as the admissible set. We then prove asymptotical linear convergence of the algorithms under the condition that the Hessian of the corresponding Lagrangian is elliptic on the tangent space of the Grassmann manifold at the minimizer.

关键词： Eigenvalue computation Grassmann manifolds Optimization Orthogonalityconstraints Hartree-Fock theory Density functional theory PINVIT

Synaptic mechanisms of cadmium neurotoxicity

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Neural Regeneration Research 2021年第9期16卷 1762-1763页

作者： Andrei N.Tsentsevitsky alexey M.Petrov Laboratory of Biophysics of Synaptic Processes Kazan Institute of Biochemistry and BiophysicsFederal Research Center“Kazan Scientific Center of RAS”2/31 Lobachevsky StreetBox 30Kazan420111Russia University 49 Butlerova StreetKazan420012Russia

Cadmium(Cd) is a toxic heavy metal ubiquitously distributed in the environment(water, air, food, smoke) with extreme ability to accumulate in the human body due to its delayed clearance(half-life time 15–30 years).

关键词： cadmium extreme accumulate

Virtual geographic environments in socio-environmental modeling:a fancy distraction or a key to communication?

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International Journal of Digital Earth 2018年第4期11卷 408-419页

作者： alexey Voinov ArzuÇöltekin Min Chen Ghassan Beydoun Faculty of Geoscience and Earth Observation(ITC) University of TwenteAE EnschedeThe Netherlands Department of Geography University of ZurichZurichSwitzerland Key Laboratory of Virtual Geographic Environment(Ministry of Education of PRC) Nanjing Normal UniversityNanjingPeople’s Republic of China Faculty of Engineering and IT University of Technology SydneyUltimoAustralia

Modeling and simulation are recognized as effective tools for management and decision support across various disciplines;however,poor communication of results to the end users is a major obstacle for properly using and understanding model *** can play an essential role in making modeling results accessible for management and *** reality(VR)and virtual geographic environments(VGEs)are popular and potentially very rewarding ways to visualize socio-environmental ***,there is a fundamental conflict between abstraction and realism:models are goal-driven,and created to simplify reality and to focus on certain crucial aspects of the system;VR,in the meanwhile,by definition,attempts to replicate reality as closely as *** elevated realism may add to the complexity curse in modeling,and the message might be diluted by too many(background)*** is also connected to information overload and cognitive ***,modeling is always associated with the treatment of uncertainty–something difficult to present in *** this paper,we examine the use of VR and,specifically,VGEs in socio-environmental modeling,and discuss how VGEs and simulation modeling can be married in a mutually beneficial way that makes VGEs more effective for users,while enhancing simulation models.

关键词： Complexity uncertainty virtual reality stakeholders cognition users

Accurate and efficient band-gap predictions for metal halide perovskites at finite temperature

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npj Computational Materials 2022年第1期8卷 2267-2279页

作者： Haiyuan Wang alexey Tal Thomas Bischoff Patrick Gono Alfredo Pasquarello Chaire de Simulationàl’Echelle Atomique(CSEA) Ecole Polytechnique Fédérale de Lausanne(EPFL)LausanneCH-1015Switzerland

We develop a computationally efficient scheme to accurately determine finite-temperature band gaps for metal halide perovskites belonging to the class ABX_(3)(A=Rb,Cs;B=Ge,Sn,Pb;and X=F,Cl,Br,I).First,an initial estimate of the band gap is provided for the ideal crystalline structure through the use of a range-separated hybrid functional,in which the parameters are determined non-empirically from the electron density and the high-frequency dielectric ***,we consider two kinds of band-gap corrections to account for spin-orbit coupling and thermal vibrations including zero-point *** particular,the latter effect is accounted for through the special displacement method,which consists in using a single distorted configuration obtained from the vibrational frequencies and eigenmodes,thereby avoiding lengthy molecular *** sequential consideration of both corrections systematically improves the band gaps,reaching a mean absolute error of 0.17 eV with respect to experimental *** computational efficiency of our scheme stems from the fact that only a single calculation at the hybrid-functional level is required and that it is sufficient to evaluate the corrections at the semilocal level of *** scheme is thus convenient for the screening of large databases of metal halide perovskites,including large-size systems.

关键词： theory. perovskite halide

Uncertainty of Climate Response to Natural and Anthropogenic Forcings Due to Different Land Use Scenarios

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Advances in Atmospheric Sciences 2011年第5期28卷 1215-1232页

作者： alexey V.ELISEEV Igor I.MOKHOV A. M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences3 Pyzhevsky 119017 Moscow Russia

The *** Institute of Atmospheric Physics,Russian Academy of Sciences （IAP RAS） climate model （CM） of intermediate complexity is extended by a spatially explicit terrestrial carbon cycle *** experiments with the IAP RAS CM are performed forced by the reconstructions of anthropogenic and natural forcings for the 16th to the 20th centuries and by combined SRES （Special Report on Emission Scenarios） A2-LUH （Land Use Harmonization） anthropogenic scenarios for the 21st ***,the impact of uncertainty in land-use scenarios on results of simulations with a coupled climate-carbon cycle model is *** simulations of the model realistically reproduced historical changes in carbon cycle *** the IAP RAS CM,climate warming reproduced in the 20th and 21st centuries enhanced terrestrial net primary production but terrestrial carbon uptake was suppressed due to an overcompensating increase in soil *** year 2100,the simulations the model forced by different land use scenarios diverged markedly,by about 70 Pg （C） in terms of biomass and soil carbon stock but they differed only by about 10 ppmv in terms of atmospheric carbon dioxide content.

关键词： terrestrial carbon cycle climate model anthropogenic scenarios uncertainty in projections