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Swampland dS conjecture in mimetic f(R,T)gravity

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Communications in Theoretical Physics 2022年第8期74卷 101-115页

作者： S Noori Gashti j sadeghi S Upadhyay M R Alipour Department of Physics Faculty of Basic SciencesUniversity of Mazandaran PO Box 47416-95447BabolsarIran Department of Physics K.L.S.CollegeNawadaBihar 805110India Department of Physics Magadh UniversityBodh GayaBihar 824234India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PuneMaharashtra 411007India School of Physics Damghan UniversityDamghan ***Iran

In this paper,we study a theory of gravity called mimetic f(R,T)in the presence of swampland dS *** this purpose,we introduce several inflation solutions of the Hubble parameter H(N)from f(R,T)=R+δT gravity model,in which R is Ricci scalar,and T denotes the trace of the energy–momentum ***,δand N are the free parameter and a number of e-fold,*** we calculate quantities such as potential,Lagrange multiplier,slow-roll,and some cosmological parameters such as nsand *** we challenge the mentioned inflationary model from the swampland dS *** discuss the stability of the model and investigate the compatibility or incompatibility of this inflationary scenario with the latest Planck observable data.

关键词： mimetic f(R,T)gravity Lagrange multiplier swampland conjecture

Rotating Charged Hairy Black Hole in(2+1) Dimensions and Particle Acceleration

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Communications in Theoretical Physics 2014年第9期61卷 358-362页

作者： j.sadeghi B.Pourhassan H.Farahani Department of Physics Islamic Azad University-Ayatollah Amoli Branch P.O. Box 678 Amol Iran Young Researchers Club Ayatollah Amoli Branch Islamic Azad University Amol Iran Department of Physics Damghan University Damghan Iran

In this paper, we construct rotating charged hairy black hole in(2+1) dimensions for infinitesimal black hole charge and rotation parameters. Then we consider this black hole as particle accelerator and calculate the centerof-mass energy of two colliding test particles near the rotating charged hairy black hole in(2+1) dimensions. As we expected, the center-of-mass energy has infinite value.

关键词： particle acceleration 3D black hole thermodynamics

Stability of Dirac Equation in Four-Dimensional Gravity

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Chinese Physics Letters 2017年第6期34卷 10-13页

作者： F. Safari H. jafari j. sadeghi S. j. johnston D. Baleanu Department of Mathematics University of Mazandaran Babolsar Iran Physics Department University of Mazandaran Babolsar 4716-95447 Iran Department of Mathematical Sciences University of South Africa UNISA 0003 South Africa Department of Mathematics Faculty of Art and Science Cankaya University Balgat 06530 Turkey Institute of Space Sciences Magurele-Bueharest Romania

We introduce the Dirac equation in four-dimensional gravity which is a generally covariant form. We choose the suitable variable and solve the corresponding equation. To solve such equation and to obtain the corresponding bispinor, we employ the factorization method which introduces the associated Laguerre polynomial. The asso- ciated Laguerre polynomials help us to write the Dirac equation of four-dimensional gravity in the form of the shape invariance equation. Thus we write the shape invariance condition with respect to the secondary quantum number. Finally, we obtain the spinor wave function and achieve the corresponding stability of condition for the four-dimensional gravity system.

关键词： Stability of Dirac Equation in Four-Dimensional Gravity

The Harmonic Oscillator with Random Damping in Non-Markovian Thermal Bath

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World journal of Mechanics 2016年第8期6卷 238-248页

作者： N. j. Hassan A. Pourdarvish j. sadeghi Department of Statistics Faculty of Mathematical Sciences University of Mazandran Babolsar Iran Department of Physics Faculty of Basic Science University of Mazandaran Babolsar Iran

In this paper, we define the harmonic oscillator with random damping in non-Markovian thermal bath. This model represents new version of the random oscillators. In this side, we derive the overdamped harmonic oscillator with multiplicative colored noise and translate it into the additive colored noise by changing the variables. The overdamped harmonic oscillator is stochastic differential equation driving by colored noise. We derive the change in the total entropy production (CTEP) of the model and calculate the mean and variance. We show the fluctuation theorem (FT) which is invalid at any order in the time correlation. The problem of the deriving of the CTEP is studied in two different examples of the harmonic potential. Finally, we give the conclusion and plan for future works.

关键词： Random Damping Total Entropy Non-Markovian Bath Fluctuation Theorem Additive Colored Noise

Field investigation on effects of railway track geometric parameters on rail wear

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1846-1855页

作者： sadeghi j. AKBARI B. School of Railway Engineering Iran University of Science and Technology Narmak Tehran Iran

Rail wear has dramatic impact on track performance, ride quality and maintenance costs. The amount of rail wear is influenced by various elements among which geometric parameters play an important role. The amount of wear in Iran’s railway lines and its imposed maintenance costs oblige us to make modifications on the various geometrical parameters. In order to ensure the effectiveness of these changes, it is necessary to investigate these parameters and their effects on the wear. This research is aimed at studying the effects of different track geometrical parameters on the vertical and lateral wear by conducting a three phase field investigation. The first phase was carried out at the switches of a station, the second phase at a straight line, and the third at a curved line out of the station. The results obtained are analyzed and the role of each track geometrical parameter in the rail wear is discussed. Recommendations for prevention or reduction of rail wear are presented.

关键词： Rail wear Vertical and lateral wear Superelevation Gauge Longitudinal slope Track geometry

Quintessence Cosmology with an Effective Λ-Term in Lyra Manifold

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Chinese Physics Letters 2015年第10期32卷 174-177页

作者： KhurshudyanM. Pasqua A sadeghi j. Farahani H Chair of Theoretical Physics and Physics Teaching Methods Armenian State Pedagogical University Yerevan 375010 Republic of Armenia Department of Physics University of Trieste Trieste 234127 Italy Department of Physics University of Mazandaran Babolsar 47416-95447 Iran

We study quintessence cosmology with an effective A-term in Lyra manifold. We consider three different models by choosing variable A depending on time, the Hubble parameter and the energy density of dark matter and dark energy. Dark energy is assumed as quintessence which interacts with the dark matter. Using numerical analysis we investigate the behavior of cosmological parameters in three different models and compare our results with observational data. State-finder diagnostic is also performed for all models.

关键词： Quintessence Cosmology with an Effective Term in Lyra Manifold

Performance of the geometric approach to fault detection and isolation in SISO,MISO,SIMO and MIMO systems

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1443-1451页

作者： RAHIMI N. sadeghi M. H. MAHjOOB M. j. Mechanical Engineering Department University of TabrizTabriz ***Iran Mechanical Engineering Department University of TehranTehran ***Iran

In this paper, a geometric approach to fault detection and isolation （FDI） is applied to a Multiple-Input Multipie-Output （MIMO） model of a frame and the FDI results are compared to the ones obtained in the Single-Input Single-Output （SISO）, Multiple-Input Single-Output （MISO）, and Single-Input Multiple-Output （SIMO） cases. A proper distance function based on parameters obtained from parametric system identification method is used in the geometric approach. ARX （Auto Regressive with exogenous input） and VARX （Vector ARX） models with 12 parameters are used in all of the above-mentioned models. The obtained results reveal that by increasing the number of inputs, the classification errors reduce, even in the case of applying only one of the inputs in the computations. Furthermore, increasing the number of measured outputs in the FDI scheme results in decreasing classification errors. Also, it is shown that by using probabilistic space in the distance function, fault diagnosis scheme has better performance in comparison with the deterministic one.

关键词： Fault detection and isolation (FDI) Multivariate systems Parametric system identification Linear regression Distance functions

Data evaluation of ^(169)Yb-producing reactions by charged particles

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Nuclear Science and Techniques 2010年第2期21卷 110-113页

作者： MAHDI sadeghi HOjAT Nadi Agricultural Medical & Industrial Research School Nuclear Science and Technology Research Institute Gohardast Karaj *** Iran Faculty of Engineering Research and Science Campus Islamic Azad University Tehran*** Iran

Excitation functions for 169Yb production on low-medium energy accelerators, i.e. proton on 169Tm and natYb, deuteron on 169Tm, and 4He ion on natEr, were calculated by the ALICE/ASH and TALYS-1.0 codes. The target thickness was predicted by SRIM code. Theoretical integral yield for each reaction was compared with experimental data. The radionuclide purity of 169Yb from the 169Tm(p, n)169Yb reaction was determined, and maximum cross section predicted by the ALICE/ASH and TALYS-1.0 codes was about 182 and 154 mb at 11 and at 9 MeV, respectively.

关键词：数据评价反应带电粒子生产大肠杆菌 SRIM 实验数据加速器

Strongly Clean Matrix Rings over a Skew Monoid Ring

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Algebra Colloquium 2023年第3期30卷 361-370页

作者： Arezou Karimimansoub Mohammad-Reza(Rafsanjani)sadeghi Department of Mathematics and Computer Science Amirkabir University of TechnologyTehranP.O.Box ***Iran

Let R be a ring with an endomorphismσ,F∪{0}the free monoid generated by U={u1,…,ut}with 0 added,and M a factor of F obtained by setting certain monomials in F to 0 such that M^(n)=0 for some *** we can form the non-semiprime skew monoid ring R[M;σ].A local ring R is called bleached if for any j∈j(R)and any u∈U(R),the abelian group endomorphisms l_(u)−r_(j) and l_(j)−r_(u) of R are *** R[M;σ],we provide various classes of both bleached and non-bleached local *** of the main problems concerning strongly clean rings is to characterize the rings R for which the matrix ring M_(n)(R)is strongly *** investigate the strong cleanness of the full matrix rings over the skew monoid ring R[M;σ].

关键词： skew monoid rings strongly clean rings matrix rings