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Relativistic Dynamics, Electromagnetic Field,and Spin, as All Quantum Effects

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Journal of Electronic Science and Technology 2017年第4期15卷 333-341页

作者： Eliade stefanescu Center of Advanced Studies in Physics Bucharest 050711 Romania Institute of Mathematics “Simion Stoilow” of the Romanian Academy Bucharest 010702 Romania

We consider a quantum particle as a wave packet in the coordinate space. When the conjugate wave packet in the momentum space is considered, we find that the group velocities of these two wave packets, which describe the particle dynamics, are in agreement with the Hamilton equations only if in the time dependent phases one considers the Lagrangian instead of the Hamiltonian which leads to the conventional Schr?dinger equation. We define a relativistic quantum principle asserting that a quantum particle has a finite frequency spectrum, with a cutoff propagation velocity c as a universal constant not depending on the coordinate system, and that any time dependent phase variation is the same in any system of coordinates. From the time dependent phase invariance,the relativistic kinematics is obtained. We consider two types of possible interactions: 1) An interaction with an external field, by a modification of the time dependent phase differential with the terms proportional to the differentials of the space-time coordinates multiplied with the components of this field four-potential, and 2)an interaction by a deformation of the space-time coordinates, due to a gravitational field. From the invariance of the time dependent phase with field components, we obtain a mechanical force of the form of Lorentz’s force, and three Maxwell equations: The Gauss-Maxwell equations for the electric and magnetic fluxes, and the Faraday-Maxwell equation for the electromagnetic induction. When the fourth equation,Ampère-Maxwell, is considered, the interaction field takes the form of the electromagnetic field. For a low propagation velocity of the particle waves, we get a packet of waves with the time dependent phases proportional to the relativistic Hamiltonian, as in Dirac’s famous theory of spin, and a slowly-varying amplitude with a phase proportional to the momentum and this velocity. In the framework of our theory, the spin is obtained as an all quantum effect, without any additio

关键词： Group velocity Maxwell equations metric tensor quantum particle spin wave packet

Effects of Thermomagnetic Treatment on Microstructure and Mechanical Properties of Rolling Bearing Steel

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Journal of Iron and Steel Research International 2010年第9期17卷 46-52页

作者： Constantin Gheorghies Ioan I stefanescu Faculty of Science Low Danube University of Galati Faculty of Mechanics Low Danube University of Galati

The influence of the thermomagnetic treatment on metallurgical and mechanical properties of the rolling bearing steel was investigated. The heating and/or cooling and tempering processes of the samples occurred in a magnetic field having certain strengths. The X-ray diffraction （XRD） patterns of the rolling bearing （RUL 1） steel samples exhibited a beneficial effect of the magnetic field on the structure, phase transformation, and tension state. An increased fatigue reliability was found for the rolling tribomodel made from thermomagnetically treated steel.

关键词： steel thermomagnetic treatment strueture phase transformation tribomodel reliability

Noninvasive assessment of portal hypertension in cirrhosis:Liver stiffness and beyond

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World Journal of Gastroenterology 2014年第45期20卷 16811-16819页

作者： Horia stefanescu Bogdan Procopet Department of Medical and Surgical Sciences University of Bologna Regional Institute of Gastroenterology and Hepatology Liver Hemodynamic Unit Hospital Clinic 3rd Medical Clinic Iuliu Hatieganu University of Medicine and Pharmacy

Liver stiffness measurement(LSM)is a good,but still limited tool to noninvasively assess complications and prognosis in patients with advanced liver *** review aims to consider the role of LSM for the diagnosis of portal hypertension-related complications and for assessment of prognosis in cirrhotic patients,and to highlight the drawbacks as well as some alternatives for improving the ***,this field is far from being closed,and deserves more *** is still a place for more carefully designed studies to find new,innovative and reliable approaches.

关键词： Liver stiffness Portal hypertension Complication Spleen stiffness Prediction

90 years of thermal analysis as a control tool in the melting of cast iron

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China Foundry 2020年第2期17卷 69-84页

作者： Doru Michael stefanescu Ramon Suarez Sung Bin Kim The Ohio State University ColumbusOH and The University of AlabamaTuscaloosaALUSA IK4-Azterlan Durango(Bizkaia)Spain Veigalan Estudio 2010 Durango(Bizkaia)Spain AnyCasting Software Co. LtdSeoulS.Korea

Since its first literature mention in conjunction with cast iron in 1931 by Esser and Lautenbusch,thermal analysis(TA)has journeyed a long *** it is an accepted and widely used tool for process control for all types of cast *** paper reviews the latest progress in the development of equipment and analysis methods that make TA successful in applications such as the estimation of chemical composition,graphitization potential,and the shape and number of graphite *** potential and limitations of the prediction of shrinkage defects propensity are analyzed in some *** of attempts at prediction of mechanical properties and shrinkage propensity are also *** graphs showing the data scattering are presented to convey the reader a better sense of the accuracy of various predictions.

关键词： thermal analysis cast iron graphite shrinkage prediction chemical composition

Lefschetz Formulae for p-Adic Groups

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Chinese Annals of Mathematics,Series B 2007年第4期28卷 463-474页

作者： anton DEITMAR Mathematisches Institut Auf der Morgenstelle 10 72076 TübingenGermany.

In this paper, Lefschetz formulae for torus actions on p-adic groups are proven. These are similar to comparable formulae for real Lie groups. Applications lie in the realm of dynamical zeta functions.

关键词： Arithmetic groups Trace formula Lefschetz formula

Efficient Numerical Valuation of Continuous Installment Options

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Advances in Applied Mathematics and Mechanics 2011年第2期3卷 141-164页

作者： anton Mezentsev anton Pomelnikov Matthias Ehrhardt IDE Halmstad UniversityBox 82330118HalmstadSweden Lehrstuhl fur Angewandte Mathematik und Numerische Analysis Fachbereich C-Mathematik und NaturwissenschaftenBergische Universitat WuppertalGaußstr.2042119 WuppertalGermany

In this work we investigate the novel Kryzhnyi method for the numerical inverse Laplace transformation and apply it to the pricing problem of continuous installment *** compare the results with the one obtained using other classical methods for the inverse Laplace transformation,like the Euler summation method or the Gaver-Stehfest method.

关键词： Installment options Black-Scholes equation numerical inverse Laplace transform Gaver-Stehfest method Euler summation method optimal stopping problem non-monotonic stopping boundary

Change in carbonate budget and composition during subduction below metal saturation boundary

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Geoscience Frontiers 2023年第1期14卷 79-100页

作者： anton Shatskiy anton V.Arefiev Konstantin D.Litasov Vernadsky Institute of Geochemistry and Analytical Chemistry Russian Academy of SciencesMoscow 119991Russia Vereshchagin Institute for High Pressure Physics Russian Academy of SciencesTroitskMoscow 108840Russia

It is generally accepted that carbonates can be subducted to the mantle depths,where they are reduced with iron metal to produce a *** this work,we found that this is not always the *** mantle carbonates from inclusions in diamonds show a wide range of cation compositions(Mg,Fe,Ca,Na,and K).Here we studied the reaction kinetics of these carbonates with iron metal at 6-6.5 GPa and 1000-1500℃.We found that the reduction of carbonate with Fe produces C-bearing species(Fe,Fe-C melt,Fe_(3)C,F e_(7)C_(3),C)and wüistite containing Na_(2)O,CaO,and *** reaction rate constants(k=△x^(2)/2t)are log-linear relative to 1/T and their temperature dependences are determined to be k_(MgcO_(3))(m^(2)/s)=4.37×10^(-3)exp[-251(kJ/mol)/RT]k_(caMg(CO_(3))2)(m^(2)/s)=1.48×10^(-3)exp[-264(kJ/mol)/RT]k_(cacO_(3))(m^(2)/s)=3.06×10^(-5)exp[-245(kJ/mol)/RT]and k_(Na_(2)cO_(3))(m^(2)/s)=1.88×10^(-10)exp[-155(kJ/mol)/RT].According to obtained results at least,45-70 vol%of carbonates preserve during subduction down to the 660-km discontinuity if no melting *** slab stagnation and warming,subsequent carbonate melting,and infiltration into the mantle saturated with iron metal are accompanied by a reduction of carbonate melt with *** established sequence of reactivity of carbonates:FeCO_(3)≥MgCO_(3)>CaMg(CO_(3))2>CaCO_(3)>>Na_(2)CO_(3),where K_(2)CO_(3)does not react at all with iron metal,implies that during reduction carbonate melt with Fe evolves toward *** above conclusions are consistent with the findings of carbonates in inclusions in diamonds from the lower mantle and high concentrations of alkalis,particularly K,in mantle carbonatite melts entrapped by diamonds from kimberlites and placers worldwide.

关键词： Carbonate Reduction of carbonate with Fe Reaction kinetics Carbonatite melt High-pressure experiment Earth's mantle

Investigating Energy Prosumer Behaviour in Crowd Energy Using an Interactive Model/Diorama

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Journal of Electronic Science and Technology 2018年第4期16卷 341-350页

作者： Christian Ritzel anton Sentic the international institute of management in technology University of Fribourg Fribourg 1700Switzerland

Smart living labs such as the one located in Fribourg(Switzerland) focus on improving wellbeing and furthering knowledge related to building the district of the future on a technical and social level. Therefore, smart living labs represent an experimental platform/space where sustainable production and consumption strategies can be tested in a protected environment. A significant change in the socioeconomic production and consumption sphere can be expected by the rise of the so-called energy prosumer. Accordingly, this article presents an interactive model for the experimental investigation of energy prosumer behavior. In this context, two potential experiments on investment and trade decisions are briefly outlined. Since(behavioral and economic) experiments are usually conducted under controlled conditions in experimental labs involving mainly undergraduate students, the presented interactive model is flexible and mobile, providing the advantage to conduct experiments nearly everywhere involving everyday citizens.

关键词： Crowd energy decentralised energy systems experiments prosumers smart grid

EXPONENTIAL INTEGRATORS FOR STOCHASTIC SCHRODINGER EQUATIONS DRIVEN BY ITO NOISE

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Journal of Computational Mathematics 2018年第2期36卷 276-309页

作者： Rikard anton David Cohen Department of Mathematics and Mathematical Statistics Umea University SE-901 87 Umea Sweden Department of Mathematics University of Innsbruck A 6020 Innsbruck Austria

We study an explicit exponential scheme for the time discretisation of stochastic SchrS- dinger Equations Driven by additive or Multiplicative It6 Noise. The numerical scheme is shown to converge with strong order 1 if the noise is additive and with strong order 1/2 for multiplicative noise. In addition, if the noise is additive, we show that the exact solutions of the linear stochastic Sehr6dinger equations satisfy trace formulas for the expected mass, energy, and momentum （i. e., linear drifts in these quantities）. Furthermore, we inspect the behaviour of the numerical solutions with respect to these trace formulas. Several numerical simulations are presented and confirm our theoretical results.

关键词： Stochastic partial differential equations Stochastic SchrSdinger equations,Numerical methods Geometric numerical integration Stochastic exponential integrators,Strong convergence Trace formulas.