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Earth crust vertical movements according to ItRF2000, ItRF2005,ItRF2008 and ItRF2014 coordinate systems and their comparing analysis

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Geodesy and Geodynamics 2018年第2期9卷 109-114页

作者： n.A.Chujkova t.G.Maximova t.S.Chesnokova A.n.Grushinsky Sternberg Astronomical Institute Lomonosov Moscow State University Schmidt Institute of Physics of Earth Russian Academy of Sciences

the analysis of Earth’s crust movement vertical velocities was made both for separate regions, and averaged on regions. As input data coordinates and velocities of earth crust points, obtained in International Coordinate Systems ItRF2000, ItRF2005,ItRF2008 on the base of processing radio interferometric(VLBI), laser(SLR), Doppler(DORIS) and GPS observations was used. For the purpose of global analysis all input velocity values were averaged in the x trapezoids. For filling trapezoids the spherical function expansion to n=36 was made. Expansion harmonic coefficients allowed determine the global characteristics of earth crust movements both for all Earth, and for separate hemispheres, polar and equatorial regions, continents and oceans. It appears, that polar regions were risen, and equatorial ones were lowered, that can indicate the modern Earth oblateness reduction. the constructed maps of vertical velocities were compared with obtained by us map of earth crust strain distribution. It is appeared, that regions of modern earth surface rising(Fennoscandia, Canada, Antarctica) coincide with regions of vertical extension strain, and the lowering regions-with compression regions. Simultaneously with the determination of harmonious coefficients the mean-square error of approximation for expansion of power n=1 n and power dispersion were determined. Whereas the results converge badly and dispersion increased with the n grows, hence we can concludes, that vertical movements do not characterized global earth crust movement and denotes the unrelated character of these movement. Seemingly, the main cause of such movement origin is the local seismic events(earthquake, volcanic eruption and so on). It confirms by our conclusions about correspondence of vertical strain maximal gradient(and therefore vertical velocities) map of the earthquake distribution. In work the detailed analysis of obtained results for separate Earth’s regions was made.

关键词： Crust movement Coordinate system Uplift

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Uranium Isotope Variations(234U/238U and 238U/235U)and Behavior of U-Pb Isotope System in the Vershinnoe Sandstone-type Uranium Deposit,Vitim Uranium Ore District,Russia

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Journal of Earth Science 2022年第2期33卷 317-324页

作者： V.n.Golubev I.V.Chernyshev B.t.Kochkin n.n.tarasov G.V.Ochirova A.V.Chugaev Institute of Geology of Ore Deposits PetrographyMineralogy and GeochemistryRussian Academy of SciencesMoscow 119017Russia

the U-Pb isotope system and uranium isotope composition(235U/238U and 234U/238U)were studied in a number of samples from the vertical section of the uranium ore body at the Vershinnoe sandstone-type deposit,Vitim uranium ore district,*** parameters were determined to broadly *** of the 234U/238U ratio from the equilibrium value indicate that the uranium ore was not completely conserved during the postore stage,and uranium was determined to continue migrating at the *** of the U-Pb isotope age value and 234U/238U isotope ratio provides an insight into the migrate direction of uranium in the ore *** broad variations(137.377–137.772)in the 238U/235U ratio over the vertical section of the ore body can be explained by the different settings of the samples relative to the ore deposition front and changes in the redox conditions when this front *** fact that theδ238U and K234/238 values are correlated indicates that the transfer of the 234U isotope into the aqueous phase may have been coupled with isotope fractionation in the 238U-235U system during the postformation uranium migration within the orebody.

关键词： sandstone-type uranium deposit U-Pb age uranium isotope composition ore deposit geology

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FEM based Electromagnetic Signature Analysis of Winding Inter-turn Short-Circuit Fault in Inverter fed Induction Motor

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CES transactions on Electrical Machines and Systems 2019年第3期3卷 309-315页

作者： Praveen Kumar n Isha t B Department of Electrical and Electronics Engineering Amrita School of EngineeringCoimbatoreAmrita Vishwa VidyapeethamIndia

the intent of this paper is to analyze the electromagnetic signature of stator winding inter-turn short-circuit fault in a closed loop speed controlled Induction Motor(IM)employing Finite Element *** winding short-circuit nearly covers 21%of faults in *** the inter-turn fault at an incipient stage is one of the challenging task in the area of fault detection of IM to prevent crucial damages in industrial *** detecting the faults in inverter fed IM under variable speed applications under varying load is one of the major issues in industrial *** the signatures of electromagnetic field contains the entire data in association with the location of rotor,stator and mechanical parts of the motor,a regular monitoring of fields in the airgap can be used to diagnose the inter-turn fault in the stator winding of *** this direction,an IM is modeled with several inter-turn fault severities like 30 turns,15 turns,5 turns&1 turn short using AnSYS Maxwell FEA tool and coupled with AnSYS Simplorer for loading *** PWM inverter with closed loop speed controlled strategy is implemented in Matlab Simulink and co-simulated with AnSYS Simplorer to integrate all the components in one common simulation platform environment for accurate design&analysis for realistic *** electromagnetic variables like flux density,flux lines and airgap flux density distribution over the machine are *** spatial FFt spectrum of radial component of flux density in the airgap contains the information related to the diagnosis of inter-turn fault at the incipient stage.

关键词： Electromagnetic fields finite element analysis inter-turn fault PWM inverter radial flux density.

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tHE HEAtInG FIELD In An ASYMMEtRIC HURRICAnE -PARt I:SCALE AnALYSIS

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Advances in Atmospheric Sciences 1985年第3期2卷 402-413页

作者： t.n.Krishnamurti,盛剑 Department of Meteorology Florida State University U.S.A Department of Meteorology Florida State University U.S.A

A closed system of equations describing an asymmetric disturbance in cylindrical geometry is expanded about a small parameter. the small parameter describes the ratio of the magnitude of divergence in the boundary layer to that above that layer. A low order system describes a gradient wind balance in the radial direction and is quasi-symmetric with respect to the pressure and temperature fields. this system can be solved as an inverse problem for a mature steady state hurricane. the procedure entails asking the questions what structure and heating distributions are required to maintain a given asymmetric distribution of the tangential velocity (i. e. the angular momentum) in steady state. the method of characteristics enables us to solve for the vertical motion. that in turn determines the radial motion from the mass continuity equation. Application of the hydrostatics to the cylindrical thermal wind equation determines the pressure and the thermal fields and finally the required heating fields are dedu

关键词： tHE HEAtInG FIELD In An ASYMMEtRIC HURRICAnE PARt I

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tHE HEAtInG FIELD In An ASYMMEtRIC HURRICAnE PARt II:RESULtS OF COMPUtAtIOnS

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Advances in Atmospheric Sciences 1985年第4期2卷 426-445页

作者： t.n.Krishnamurti,盛剑 Department of Meteorology Florida State Universjty U.S.A. Department of Meteorology Florida State Universjty U.S.A.

this is the second part of a paper on the distribution of heating fields in a hurricane. the first part dealt with the mathematical framework. the second part, i. e. the present paper deals with numerical calculations for an actual *** following sequence of calculations has been performed after the analysis and tabulation of an initial field of the tangential velocity V (r, θ, p): (1) the radial equation of motion is used to determine the geopotential heights; (2) the hydrostatic equation is used to determine the temperature field; (3) the tangential equation and the mass continuity equation are combined to obtain an omega equation whose solution determines the vertical velocity; (4) the radial velocity is next determined from the mass continuity equation; and (5) the heating function is finally determined from the first law of *** results of this study show an asymmetric banded structure (eye wall and rainband) of the vertical motion field as well as the heating field; these s

关键词： tHE HEAtInG FIELD In An ASYMMEtRIC HURRICAnE PARt II

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An AMR Capable Finite Element Diffusion Solver for ALE Hydrocodes

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Plasma Science and technology 2015年第2期17卷 109-116页

作者： A.C.FISHER D.S.BAILEY t.B.KAISER D.C.EDER B.t.n.GUnnEY n.D.MAStERS A.E.KOnIGES R.W.AnDERSOn Lawrence Livermore national Laboratory Lawrence Berkeley national Laboratory

We present a novel method for the solution of the diffusion equation on a composite AMR mesh. this approach is suitable for including diffusion based physics modules to hydrocodes that support ALE and AMR capabilities. to illustrate, we proffer our implementations of diffu- sion based radiation transport and heat conduction in a hydrocode called ALE-AMR. numerical experiments conducted with the diffusion solver and associated physics packages yield 2nd order convergence in the L2 norm.

关键词： hydrodynamic simulation heat conduction thermal radiation adaptive meshrefinement finite element method

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Effects of Weaving Laser on Weld Microstructure and Crack for Al 6k21-t4 Alloy

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Journal of Materials Science & technology 2011年第1期27卷 93-96页

作者： B.H.Kim n.H.Kang W.t.Oh C.H.Kim J.H.Kim Y.S.Kim Y.H.Park Department of Materials Science and Engineering Pusan National UniversitySan30Jangjeon-dongGeumjeong-guBusan 609-735Korea Department of Materials and Components Engineering Dong-Eui UniversityBusan 614-714Korea Advanced Joining technology team KITECH7-47Songdo-dongYeonsu-guIncheon 406-840Korea Division for Dongnam Area technology Service KITECHJisa-dongGanseo-guBusan 618-230Korea

For Al 6k21-t4 overlap weld joint,the shear-tensile strength by using the weaving laser was improved as compared to the case of linear *** the specimen of low strength,the porosity was distributed continuously along the intersection between the plates and fusion ***,for the optimized welding condition,large oval-shaped porosities were located only in the advancing track of the concave ***,the continuity of cracks and porosities played a key role to determine the ***,the weaving width was also the important parameter to control the ***,the concave part had more significant hot and cold cracking in the weld and heat-affected zone（HAZ）,respectively,than the convex part.

关键词： Weaving laser Weld microstructure Void Al alloy

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EFFECtS OF CHEMICAL MODIFICAtIOnS AnD MMt nAnOCLAY ADDItIOn On tRAnSPORt PHEnOMEnA OF nAtURALLY WOVEn COCOnUt SHEAtH/POLYEStER nAnOCOMPOSItES

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Chinese Journal of Polymer Science 2013年第8期31卷 1074-1086页

作者： n. Rajini J.t. Winowlin Jappes S. Rajakarunakaran C. Bennet Centre for Composite Materials Department of Mechanical Engineering Kalasalingam University Center for Advanced Materials Department of Mechanical Engineering Cape Institute of Technology Levengipuram

Studies on the behavior of molecular transport properties such as thermal conductivity, gas permeability, volume and surface resistivity have been carried out for the naturally woven coconut sheath （CS） fiber reinforced composites with the addition of nanoclay and chemical treatment of fiber. the compression molding technique was used to fabricate the coconut sheath/clay reinforced hybrid composites. the morphological studies such as X-ray diffractogram （XRD）, transmission electron microscopy （tEM） and scanning electron microscopy （SEM） have been carried out for polyester nanocomposites and coconut sheath fiber. the decreased gas permeability, thermal conductivity and volume and surface resistivity have been observed with increasing the weight percentage of nanoclay in polyester matrix. In chemical modifications, the alkali and silane treated coconut sheath reinforced composites have shown great influence on the transport properties due to the increasing hydrophilic nature by the topographical changes at the fiber surface. Dielectric strength has also been reported in this paper for all types of composites. Infra-red （IR） spectra have also been taken to study the physical and chemical structural changes of treated coconut sheath.

关键词： nanoclay Coconut sheath Gas permeability tEM SEM FtIR.

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two-Factor Cancelable Biometrics Authenticator

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Journal of Computer Science & technology 2007年第1期22卷 54-59页

作者：彭颖涵 Andrew t. B. J David n. C. L Faculty of Information Science and technology Multimedia University dalan Ayev Keroh Lama 75450 Melaka Malaysia

Biometrics-based authentication system offers advantages of providing high reliability and accuracy. However the contemporary authentication system is impuissance to compromise. If a biometrics data is compromised, it cannot be replaced and rendered unusable. In this paper, a cancelable biometrics-based authenticator is proposed to solve this irrevocability issue. the proposed approach is a two-factor authentication system, which requires both of the random data and facial feature in order to access the system. In this system, tokenized pseudo-random data is coupled with momentbased facial feature via inner product algorithm. the output of the product is then discretized to generate a set of private binary code, coined as 2factor-Hashing code, which is acted as verification key. If this biometrics-based verification key is compromised, a new one can be issued by replacing a different set of random number via token replacement. then, the compromised one is rendered completely useless. this feature offers an extra protection layer against biometrics fabrication since the verification code is replaceable. Experimental results demonstrate that the proposed system provides zero Equal Error Rate in which there is a clear separation in between the genuine and the imposter distribution populations.

关键词： cancelable biometrics face recognition Geometric moments,pseudo Zernike moment

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thermodynamic Aspects of nanostructured CoAl Intermetallic Compound during Mechanical Alloying

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Journal of Materials Science & technology 2011年第7期27卷 601-606页

作者： S.n. Hosseini t. Mousavi F. Karimzadeh M.H. Enayati Department of Materials Engineering Nanotechnology and Advanced Materials Institute Isfahan University of Technology84156-83111 Iran

the nanostructured CoAl intermetallic compound was produced by mechanical alloying （MA） of the Co50Al50 elemental powder mixture in a planetary high energy ball mill. the ordered B2-CoAl structure with the grain size of about 6 nm was formed via a gradual reaction after 10 h of MA. A thermodynamic analysis of the process was also done. the results showed that the intermetallic compound of CoAl had the minimum Gibbs free energy compared to solid solution and amorphous states indicating the initial MA product was the most stable phase in the Co-Al system which was changed to a partially disordered structure with a steady long-range order of 0.82 at further milling. this amount of disordering caused the enthalpy of final product to show an increase of about 5.1 kJ·mol-1. Calculation of enthalpy related to the triple defect formation revealed that the enthalpy required for Al anti-sites formation was about 3 times greater than that for Co anti-sites formation.

关键词： Intermetallics CoAl nanostructured materials Mechanical alloying thermodynamics

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