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Function fitting for modeling seasonal normalized difference vegetation index time series and early forecasting of soybean yield

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The Crop Journal 2022年第5期10卷 1452-1459页

作者： alexey Stepanov Konstantin Dubrovin Aleksei Sorokin Far Eastern Agriculture Research Institute Vostochnoe680521 KhabarovskRussia Computing Center of the Far Eastern Branch of the Russian Academy of Sciences 680000 KhabarovskRussia

Forecasting crop yields based on remote sensing data is one of the most important tasks in *** is the main crop in the Russian Far *** is desirable to forecast soybean yield as early as possible while maintaining high *** study aimed to investigate seasonal time series of the normalized difference vegetation index(NDVI) to achieve early forecasting of soybean *** research used data from the Moderate Resolution Image Spectroradiometer(MODIS),an arable-land mask obtained from the VEGA-Science web service,and soybean yield data for 2008-2017 for the Jewish Autonomous Region(JAR) *** approximating functions were fitted to model the NDVI time series:Gaussian,double logistic(DL),and quadratic and cubic *** the period from calendar weeks 22-42(end of May to mid-October),averaged over two districts,the model using the DL function showed the highest accuracy(mean absolute percentage error-4.0%,root mean square error(RMSE)-0.029,P <0.01).The yield forecast accuracy of prediction in the period of weeks 25-30 in JAR municipalities using the parameters of the Gaussian function was higher(P <0.05) than that using the other *** mean forecast error for the Gaussian function was 14.9% in week 25(RMSE was0.21 t ha) and 5.1%-12.9% in weeks 26-30(RMSE varied from 0.06 to 0.15 t ha) according to the2013-2017 *** weeks 31-32,the error was 5.0%-5.4%(RMSE was 0.07 t ha) using the Gaussian parameters and 7.4%-7.7%(RMSE was 0.09-0.11 t ha) for the DL *** the method was applied to municipal districts of other soy-producing regions of the Russian Far *** was0.14-0.32 t hain weeks 25-26 and did not exceed 0.20 t hain subsequent weeks.

关键词： NDVI Function fitting Early prediction Yield Soybean

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Previously unknown behavior in parasitic cuckoo females:male-like vocalization during migratory activity

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Avian Research 2021年第1期12卷 1-16页

作者： Swetlana G.Meshcheryagina alexey Opaev Institute of Plant and Animal Ecology Ural Branch of the Russian Academy of SciencesEkaterinburgRussia A.N.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia

Background:In the last decade,enigmatic male-like cuckoo calls have been reported several times in East *** calls exhibited a combination of vocal traits of both Oriental Cuckoo(Cuculus optatus)and Common Cuckoo(Cuculus canorus)advertising calls,and some authors therefore suggested that the enigmatic calls were produced by either Common×Oriental Cuckoo male hybrids or Common Cuckoo males having a gene ***,the exact identity of calling birds are still ***:We recorded previously unknown male-like calls from three captive Oriental Cuckoo females,and compared these calls with enigmatic vocalizations recorded in the wild as well as with advertising vocalizations of Common and Oriental Cuckoo *** achieve this,we measured calls ***,we video-recorded captive female emitting male-like calls,and compared these recordings with the YouTube recordings of calling males of both Common and Oriental Cuckoos to get insight into the mechanism of call ***:The analysis showed that female male-like calls recorded in captivity were similar to enigmatic calls recorded in the ***,Oriental Cuckoo females might produce the latter *** features of these female calls appeared to be unusual among ***,females produced male-like calls at the time of spring and autumn migratory activity and on migration in the *** of this,functional significance of this call remained ***,the male-like female call unexpectedly combined features of both closed-mouth(closed beak and simultaneous inflation of the‘throat sac')and open-mouth(prominent harmonic spectrum and the maximum neck extension observed at the beginning of a sound)vocal ***:The Cuculus vocalizations outside the reproductive season remain poorly ***,we found for the first time that Oriental Cuckoo females can produce male-like calls in that *** of its rarity,this call might be an ***,fe

关键词： Closed-mouth vocal behavior Cuckoo call Cuculus optatus Female song Male-like vocalization

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Influence of Features of Interphase Boundaries on Mechanical Properties and Fracture Pattern in Metal-Ceramic Composites

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Journal of Materials Science & Technology 2013年第11期29卷 1025-1034页

作者： Sergey Psakhie Vladimir Ovcharenko Baohai Yu Evgeny Shilko Sergey Astafurov Yury Ivanov alexey Byeli alexey Mokhovikov Institute of Strength Physics and Materials Science Siberian Branch of the Russian Academy of Sciences Institute of High Technology Physics Tomsk Polytechnic University Shenyang National Laboratory for Materials Science Institute of High Current Electronics Siberian Branch of the Russian Academy of Sciences Physical-Technical Institute Yurga Technological Institute Tomsk Polytechnic University

The results of a theoretical study on the influence of strength of interphase boundaries in metal-ceramic composite on macroscopical characteristics of composite response such as strength, deformation capacity, fracture energy and fracture pattern are presented. The study was conducted by means of computer-aided simulation by means of movable cellular automaton method taking account of a developed ＂mesoscopical＂ structural model of particle-reinforced composite. The strength of interphase boundaries is found to be a key structural factor determining not only the strength properties of metal-ceramic composite, but also the pattern and rate of fracture. The principles for achievement of the high-strength values of particle/binder interfaces in the metal-ceramic composition due to the formation of the wide transition zones （areas of variable chemical composition） at the interphase boundaries are discussed. Simulation results confirm that such transition zones provide a change in fracture mechanism and make the achievement of a high-strength and a high deformation capacity of metal-ceramic composite possible.

关键词： Metal--ceramic composites Particle-reinforced composite Interphase boundaries Discrete element based analysis Strength and fracture energy Fracture pattern

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Evolution of stress fields during the supercontinent cycle

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Geodesy and Geodynamics 2022年第4期13卷 363-375页

作者： Alexander Bobrov alexey Baranov Robert Tenzer Schmidt Institute of Physics of the Earth Russian Academy of SciencesMoscowRussia Institute of Earthquake Prediction Theory and Mathematical Geophysics Russian Academy of SciencesMoscowRussia Department of Land Surveying and Geo-Informatics Hong Kong Polytechnic UniversityHong KongChina

We investigate the evolution of stress fields during the supercontinent cycle using the 2D Cartesian geometry model of thermochemical convection with the non-Newtonian rheology in the presence of floating deformable *** the course of the simulation,the supercontinent cycle is implemented several *** number of continents considered in our model as a function of time oscillates around *** lifetime of a supercontinent depends on its *** results suggest that immediately before a supercontinent breakup,the over-lithostatic horizontal stresses in it(referring to the mean value by the computational area)are tensile and can reach-250 *** the same time,a vast area beneath a supercontinent with an upward flow exhibits clearly the over-lithostatic compressive horizontal stresses of 50-100 МРа.The reason for the difference in stresses in the supercontinent and the underlying mantle is a sharp difference in their *** large parts of the mantle,the over-lithostatic horizontal stresses are in the range of±25 MPa,while the horizontal stresses along subduction zones and continental margins are significantly *** the process of continent-to-continent collisions,the compressive stresses can approximately reach 130 MPa,while within the subcontinental mantle,the tensile over-lithostatic stresses are about-50 *** dynamic topography reflects the main features of the su-percontinent cycle and correlates with real *** the breakup and immediately after the disin-tegration of the supercontinent,continents experience maximum *** the supercontinent cycle,topographic heights of continents typically vary within the interval of about±1.5 km,relatively to a mean *** maxima of orogenic formations to about 2-4 km are detected along continent-to-continent collisions as well as when adjacent subduction zones interact with continental margins.

关键词： Supercontinent cycle Floating deformable continents Thermochemical convection Horizontal stresses Dynamic topography

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Determining effects of impact loading on residual strength of fiber-metal laminates with grid-characteristic numerical method

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Chinese Journal of Aeronautics 2021年第7期34卷 1-12页

作者： Katerina BEKLEMYSHEVA Vasily GOLUBEV Igor PETROV alexey VASYUKOV Moscow Institute of Physics and Technology DolgoprudniyRussia

The Grid-Characteristic numerical Method(GCM)that is quite common in solving aero and hydrodynamic problems can also be applied for mechanics of *** allows to implement complex border and contact conditions,including the non-reflecting border and the destructible *** this conditions are very important for the precise and effective modeling of LowVelocity Impacts(LVI)on fiber and Fiber-Metal Laminates(FML)and the resulting Barely Visible Impact Damage(BVID)that influences the residual strength of a composite aircraft *** is the type of damage that is not visible by the naked eye and can be hardly detected by a standard ultrasound equipment that is used for regular *** can appear during any weak impacts like bird strike or *** its influence on the residual strength of the part is very important to define the priorities of development of ultrasound *** this paper,the GCM was applied for a full cycle of loading of an FML aircraft cover *** FML consisted of a Carbon Fiber Reinforced Polymer(CFRP)and a single titanium layer on the upper *** cycle of loading in a single calculation consisted of an LVI caused by a small striker and a comparatively slow compressive in-plane ***-dimensional patterns of velocity and stress distributions over the time of calculation are *** patterns,obtained via the Hashin failure criterion are given and analyzed.

关键词： Fiber-metal laminate Grid-characteristic method Low-velocity impact Numerical modeling Residual strength

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Roof model recommendation for complex buildings based on combination rules and symmetry features in footprints

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International Journal of Digital Earth 2018年第10期11卷 1039-1063页

作者： Xuke Hu Hongchao Fan alexey Noskov GIScience Research Group Institute of GeographyHeidelberg UniversityHeidelbergGermany School of Remote Sensing and Information Engineering Wuhan UniversityWuhanPeople’s Republic of China

Currently,very few roof shape information for complex buildings is available on ***,additional data requirements(e.g.3D point clouds)limit the applicability of many roof reconstruction *** mitigate this issue,we propose an approach to roof shape recommendations for complex buildings by exploring the inherited characteristics of building footprints:the disclosure of rectangles combinations in a partition of footprints and the symmetrical features of ***,it decomposes a complex footprint into rectangles by using an advanced minimal non-overlapping cover ***,a graph-based symmetry detection algorithm is proposed to identify all the symmetrical sub-clusters in ***,a set of selection rules are defined to rank partitions,and the best ones are chosen for roof shape ***,a set of combination rules and a symmetry rule are *** enables to evaluate the probability of a footprint being a certain combination of roof *** results show the growth of the probability of correctly recommending roof shapes for single rectangles and buildings from a prior probability of 17–45%and from a prior probability of 0.29–14.3%,removing 60%and 93%of the incorrect roof shape options,respectively.

关键词： Roof recommendation footprint decomposition symmetry detection symmetry rule combination rules intrinsic roof reconstruction OpenStreetMap

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Categories and Weak Equivalences of Graded Algebras

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Algebra Colloquium 2019年第4期26卷 643-664页

作者： alexey Gordienko Ofir Schnabel James Zhang Department of Higher Mathematics Moscow State Technical University of Civil Aviation Kronshtadtsky Boulevardd.20125993 MoscowRussia Department of Mathematics ORT Braude College2161002 KarmiclIsrael 不详

In the study of the structure of graded algebras(such as graded ideals,graded subspaces,and radicals)or graded polynomial identities,the grading group can be replaced by any other group that realizes the same *** we come to the notion of weak equivalence of gradings:two gradings are weakly equivalent if there exists an isomorphism between the graded algebras that maps each graded component onto a graded *** group grading on an algebra can be weakly equivalent to G-gradings for many different groups G;however,it turns out that there is one distinguished group among them,called the universal group of the *** this paper we study categories and functors related to the notion of weak equivalence of *** particular,we introduce an oplax 2-functor that assigns to each grading its support,and show that the universal grading group functor has neither left nor right adjoint.

关键词： algebra grading adjoint functor oplax 2-functor (co)limit

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Influence of polyolefin fibers on the strength and deformability properties of road pavement concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 407-417页

作者： Olga Smirnova alexey Kharitonov Yuriy Belentsov Department of Constructing Mining Enterprises and Underground Structures Saint-Petersburg Mining UniversitySaint Petersburg 199106Russia Department of Technology of Building Materials and Metrology Saint-Petersburg State University of Architecture and Civil EngineeringSaint Petersburg 190005Russia Department of Building Materials and Technologies Emperor Alexander I St.Petersburg State Transport UniversitySaint Petersburg 190031Russia

Influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson’s coefficient) and the abrasion resistance of cement concrete with water-to-cement ratio within 0.31 e0.55 were stated in the *** ways of fibers introduction into fresh concrete were investigated. It was shown that the fibers introduction method and procedure of mixing are the ways to improve the fibers uniform distribution in fresh concrete. The increase of the bending tensile strength and the uniaxial tensile strength of concrete with fibers reinforcement in comparison with the reference concrete was observed with the water-to-cement ratio decrease. The increase of uniaxial tensile strength at age of 28 days for concrete with macrofibers in amount of4.5 kg/m^3 was 23% and 29%;for macrofibers in quantity of 3 kg/m^3 was 19% and 26% with water-cement ratio equal to 0.49 and 0.31, respectively. The maximum reduction of abrasion in the range of 7.5%e10% was observed in concrete with water-to-cement ratio within0.44 e0.55 for all investigated types of fibers. The influence of fibers on the concrete abrasion with lower W/C ratio was negligible. The results can contribute to the rational use of modified polyolefin fibers in road pavement concrete.

关键词： Road pavement concrete Polyolefin fibers Strength Elastic modulus Abrasion Water-to-cement ratio

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Evaluation of opening of fractures in the Logovskoye carbonate reservoir, Perm Krai, Russia

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Petroleum Research 2021年第2期6卷 137-143页

作者： Dmitriy A.Martyushev alexey Yurikov Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPerm614990Russia WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerth6151Australia

The development of naturally fractured carbonate reservoirs is extremely challenging. Such reservoirshave a dual pore structure consisting of low-permeable matrix with large pore volume and highpermeable fractures constituting main paths for fluid flow. Productivity of wells drilled in such formations tends to decrease rapidly due to the drop in the reservoir pressure and closure of ***, it is crucial to monitor opening of fractures for the effective development of carbonate reservoirs. Three methods for monitoring of opening of fractures including tracer indicators method,Warren and Root method and Victorin’s empirical relation, are applied in the Logovskoye oil reservoir, acarbonate Tournaisian-Famennian formation in Upper Kama Region, Perm Krai, Russia. The threemethods provide reliable estimation of the opening of fractures, which match the reported laboratorydata obtained on thin sections of core samples. The limitations of each method are also discussed. Thetracer indicator method is time-consuming, the Warren and Root method includes hydrodynamic studiesand requires shutdown of wells influencing the oil production, and the application of Victorin’s relationrequires estimation of initial opening and current compressibility of fractures, which can be done usinganalysis of cores or tracer indicators studies. The appropriate method for monitoring of opening offractures should be chosen according to available resources, time, and economic targets of the development project.

关键词： Carbonates Well tests Tracer indicators Warren and Root method Indicator injection

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Glial decline and loss of homeostatic support rather than inflammation defines cognitive aging

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Neural Regeneration Research 2022年第3期17卷 565-566页

作者： Alexei Verkhratsky Natalia Lazareva alexey Semyanov Faculty of Biology Medicine and HealthThe University of ManchesterManchesterUK Achucarro Center for Neuroscience IKERBASQUEBasque Foundation for ScienceBilbaoDepartment of NeurosciencesUniversity of the Basque Country UPV/EHU and CIBERNEDLeioaSpain Sechenov First Moscow State Medical University MoscowRussia Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of SciencesFaculty of BiologyMoscow State UniversityMoscowRussia

The preservation of cognitive longevity and arresting the pandemic of senile dementia engulfing the modern world is arguably the major challenge faced by biomedical research in the 21st *** is the leading risk factor for neurodegenerative diseases and vascular dementia,and yet there is a clear distinction between physiological and pathological brain aging.

关键词： inflammation senile aging

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