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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 *** 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 *** well,the correlation between the velocity characteristics and geoelectric properties was *** 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 ***,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

Territorial Resilience Through Visibility Analysis for immediate Detection of Wildfires integrating Fire Susceptibility,Geographical Features,and Optimization Methods

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international Journal of Disaster Risk Science 2022年第4期13卷 621-635页

作者： Stavros Sakellariou George Sfoungaris olga Christopoulou Department of Agriculture Crop Production and Rural Environment University of Thessaly38446 VólosGreece Department of Planning and Regional Development University of Thessaly38334 VólosGreece Computer Science Department University of Crete70013 HeraklionCreteGreece

Climate change effects tend to reinforce the frequency and severity of wildfires worldwide,and early detection of wildfire events is considered of crucial *** primary aim of this study was the spatial optimization of fire resources(that is,watchtowers)considering the interplay of geographical features(that is,simulated burn probability to delimit fire vulnerability;topography effects;and accessibility to candidate watchtower locations)and geo-optimization techniques(exact programming methods)to find both an effective and financially feasible solution in terms of visibility coverage in Chalkidiki Prefecture of northern *** integration of all geographical features through the Analytical Hierarchy Process indicated the most appropriate territory for the installment of *** analysis guaranteed the independence and proximity of location options(applying spatial systematic sampling to avoid first order redundancy)across the *** conjunction of the above processes yielded 654 candidate watchtower positions in 151,890 ha of *** algorithm was designed to maximize the joint visible area and simultaneously minimize the number of candidate locations and overlapping effects(avoiding second order redundancy).The results indicate four differentiated location options in the study area:(1)75locations can cover 90%of the forests(maximum visible area);(2)47 locations can cover 85%of the forests;(3)31locations can cover 80.2%of the forests;and(4)16 locations can cover 70.6%of the *** last option is an e fficient solution because it covers about 71%of the forests with just half the number of watchtowers that would be required for the third option with only about 10%additional forest ***,the final choice of any location scheme is subject to agency priorities and their respective financial flexibility.

关键词： Burn probability Greece Spatial optimization Topography effects Viewshed coverage Watchtowers Wildfire detection

Modification of Steel Surface Using the Laser Energy olga Chudina

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Journal of Surface Engineered Materials and Advanced Technology 2014年第4期4卷 181-188页

作者： olga Chudina Moscow Automobile and Road Construction State Technical University (MADi) Moscow Russia

The article is devoted to surface hardening of steels by alloying with the use of laser energy. Two combined technologies were proposed: first—laser alloying by nitride-forming elements followed by nitriding, and second—the local laser alloying followed by metallization in atmosphere of ammonia. it is shown that laser alloying in continuous radiation forms a layer with a homogeneous fine-grained structure with thickness of 600 microns. The subsequent nitriding increases the microhardness of the surface layer of low-carbon steels to 20,000 MPa, increases wear-resistance in a 3 - 15 times and crack resistance in a 1.5 times. Two-stage technology of metallization allows getting diffusion layer on the surface of steels with the thickness, which is 1.5 - 2 times higher than after traditional metallization. in addition, this method of surface modification can significantly reduce the temperature of diffusion metallization and reduce the processing time to 3 hours. The optimal regimes of both technologies, which provide homogeneous multiphase diffusion layers with high hardness and wear resistance, were determined.

关键词： Laser Alloying Nitriding Metallization Diffusion Layer

Evolutionary status of T Tauri stars

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Research in Astronomy and Astrophysics 2018年第8期18卷 103-110页

作者： olga Eretnova Alexander Dudorov Physics Department Chelyabinsk State University

The problem of determining the masses and ages of T Tauri star （TTS） using their evolu- tionary status is discussed. We test four pre-main sequence evolutionary models using well determined observational parameters of 12 binary TTSs and two binary red dwarfs. it is shown that the masses derived using the tracks of all models are in good agreement with flhe masses obtained from the obser- vations of TTSs with masses M 〉 0.7 Me （mean error ε,- 10%）. Low-mass stars with M ≤ 0.7 M⊙ have significantly greater mean error; e - 50% for the tracks of Bressan et al. and Chen et al., and e - 30% for the other tracks. The isochrones of all tested evolutionary models diverge for stars with masses M ≤ 0.7 M⊙. The difference increases with the mass decrease and can reach 10% of Kelvin- Helmholtz time for stars with mass M = 0.2 Me. The ages of most of the considered TTSs are smaller than the Kelvin-Helmholtz time. This confirms their evolutionary status of being pre-main sequence stars.

关键词： stars pre-main sequence stars - stars binaries - Hertzsprung-Russell diagram

Dynamics and genesis of calcic accumulations in soils and sediments of the Argentinean Pampa

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international Journal of Sediment Research 2015年第3期30卷 179-189页

作者： Alsu Kuznetsova olga Khokhlova Department of Renewable resources University of Alberta Edmonton institute of Physicochemical and Biological Problems of Soil Science RAS Puschino

Micromorphology of calcic accumulations(calcite,whewellite and gypsum) and geochemical indices were considered as indicators of genesis and evolution of pedogenic accumulations in soils and paleosediments of the Argentinean *** groups of separate and independent calcic accumulations were studied using scanning electron microscopy:(i) in situ Argiudolls,reflecting the current soil formation;(ii) in the layers of calcrete(locally named tosca).reflecting the past environments and conditions of these layers *** pedogenic gypsum accumulations in Argiudolls were described and possible ways of their formation were *** analyses of morphology of carbonate accumulations and geochemical indices in different horizons of Argiudolls and layers of tosca showed that the tosca is paleopedocomplex with complicated formation *** of current environment on tosca morphology is absent,so it is possible to use these pedofeatures for paleoreconstructions in further studying.

关键词： Carbonate accumulations Gypsum accumulations Pedogenic rhizoliths Tosca

WAVELET-BASED ANALYSiS OF CEREBROVASCULAR DYNAMiCS iN NEWBORN RATS WiTH iNTRACRANiAL HEMORRHAGES

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Journal of innovative Optical Health Sciences 2014年第1期7卷 66-75页

作者： ALEXEY N.PAVLOV ALEXEY i.NAZiMOV olga N.PAVLOVA VLADiSLAV V.LYCHAGOV VALERY V.TUCHiN olga A.BiBiKOVA SERGEYS.SiNDEEV OXANA V.SEMYACHKiNA-GLUSHKOVSKAYA Department of Physics Saratou State University 83 Astrakhanskaya str.Saratou 410012Russia

intracranial hemorrhage(i)is a major problem of neonatal intensive *** incidence of iistypically asymptomatic and'canmot be effectively detected by standard diagnostic *** mechanisms underlying iH are unknown but there is evidence that stress-induced disorders inadrenergic regulation of cerebral venous blood flow (CVBF) are among the main *** and qualitative:could significantly advance understanding ofthe nature of i in newbornslth1sions of CVBF in newborn rats withan experimental model of *** analysis is bas ed on theDoppler optical coheavelet-based approachthat provides sensitiv external *** resultsccompanied by asupprectivity to *** show that the values0imated ithelodinto the sympathicusindicate abnormal reactions associated with the developent of *** conclude that t he revealed areactivity of the cerebral veins to adrenaline represents a possible mechanism responsible forpat hological changes in CVBF.

关键词： Brain hemorhages optical coherence tomography cerebrovascular dynamics wavelet analy sis stress.

Scheimpflug imaging of the Anterior Eye Segment during Standardized Accommodation Stimulation in Patients with Emmetropia, Myopia and Hypermetropia

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Open Journal of Ophthalmology 2023年第1期13卷 73-82页

作者： olga i. Rozanova irkutsk Branch of S. Fyodorov “Eye Microsurgery” Federal State institution of Ministry of Health of Russian Federation Ir-kutsk Russia

Understanding of the biomechanics of the accommodative apparatus in the eyes with different refraction is important for solving the problems of theoretical and practical ophthalmology. Purpose: To determine the changes of anterior eye segment dimensions during accommodation response in normal eyes and in patients with myopia, hypermetropia. Methods and Material: 116 eyes (56 patients aged from 18 to 30 years, refraction from -2.0 to + 2.0 D) were examined. All the patients underwent a full ophthalmological examination. The ocular anterior segment was imaged using a rotational Scheimpflug camera Pentacam HR (Oculus, Wetzlar, Germany) under non- and 3.0 D of accommodative demands. The statistical data were represented as the mean value ± standard deviation (M ± SD). The Shapiro-Wilk test was used to assess the normality distribution. Wilcoxon test was used for comparison. Results: Results showed an increase in the optical density of the crystalline lens, a pupil diameter decrease and changing of the iris profile during accommodation in all patients. An increase in the total corneal aberrations and decrease in the corneal spherical aberration were revealed only in emmetropic eyes. Conclusions: The accommodative response is a multicomponent process. Scheimpflug visualization revealed the differences in the accommodative response in normal and ametropic eyes.

关键词： Eye Accommodation Scheimpflug imaging Pupil Response

Mixed layer in the Sea of Japan:numerical simulation andlong-term data analysis

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Acta Oceanologica Sinica 2005年第1期24卷 76-85页

作者： TRUSENKOVA olga KHRAPCHENKOV Fyodor iSHiDA Hajime V.i.il'ichev Pacific Oceanological institute Russian Academy of Sciences Vladivostok 690041 RussiaV.I.Il'ichev Pacific Oceanological Institute Russian Academy of Sciences Vladivostok 690041 RussiaFaculty of Engineering Kanazawa University Kanazawa 920-8667 Japan

Seasonal variation and topography of the mixed layer in the Sea of Japan are studied by comparison of results from long-term observation data analysis and from numerical simulation with the MHi oceanic model (Shapiro. 1998. Marine Hydrophysical Journal, 6: 26-40). The data are retrieved from Oceanographic A tlas of the Bering Sea, Okhotsk Sea, and Japan/East Sea (Rostov, Rostov, Dmitrieva, et al. 2003. Pacific Oceanography, 1(1):70-72). The simulated and long-term patterns are compared. An impact of surface buoyancy flux, wind, and convergence/divergence of surface currents upon the mixed layer in the Sea of Japan is analyzed.

关键词： numerical modeling circuktion of the Sea of Japan mixed layer depth seasonal variation spatial patterns

GLOBAL EXiSTENCE,UNiQUENESS,AND STABiLiTY FOR A NONLiNEAR HYPERBOLiC-PARABOLiC PROBLEM iN PULSE COMBUSTiON

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Acta Mathematica Scientia 2012年第1期32卷 41-74页

作者： olga Terlyga Hamid Bellout Frederick Bloom Fermi National Laboratory Department of Mathematical Sciences Northern Illinois University

A global existence theorem is established for an initial-boundary value prob- lem, with time-dependent boundary data, arising in a lumped parameter model of pulse combustion; the model in question gives rise to a nonlinear mixed hyperbolic-parabolic sys- tem. Using results previously established for the associated linear problem, a fixed point argument is employed to prove local existence for a regularized version of the nonlinear problem with artificial viscosity. Appropriate a-priori estimates are then derived which imply that the local existence result can be extended to a global existence theorem for the regularized problem. Finally, a different set of a priori estimates is generated which allows for taking the limit as the artificial viscosity parameter converges to zero; the corresponding solution of the regularized problem is then proven to converge to the unique solution of the initial-boundary value problem for the original, nonlinear, hyperbolic-parabolic system.

关键词： pulse combustion hyperbolic-parabolic system global existence regularity