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Computer Modeling in Engineering & Sciences 2021年第12期129卷 1283-1303页

作者： arash mehraban Henry Tufo Stein Sture Richard Regueiro Department of Computer Science University of Colorado BoulderBoulderCOUSA Department of Civil Environmentaland Architectural EngineeringUniversity of Colorado BoulderBoulderCOUSA

Higher-order displacement-based finite element methods are useful for simulating bending problems and potentially addressing mesh-locking associated with nearly-incompressible elasticity,yet are computationally *** address the computational expense,the paper presents a matrix-free,displacement-based,higher-order,hexahedral finite element implementation of compressible and nearly-compressible(ν→0.5)linear isotropic elasticity at small strain with p-multigrid *** cost,solve time,and scalability of the implementation with respect to strain energy error are investigated for polynomial order p=1,2,3,4 for compressible elasticity,and p=2,3,4 for nearly-incompressible elasticity,on different number of CPU cores for a tube bending *** the context of this matrix-free implementation,higher-order polynomials(p=3,4)generally are faster in achieving better accuracy in the solution than lower-order polynomials(p=1,2).However,for a beam bending simulation with stress concentration(singularity),it is demonstrated that higher-order finite elements do not improve the spatial order of convergence,even though accuracy is improved.

关键词： Matrix-free higher-order finite element parallel linear elasticity multigrid solvers unstructured meshes

Traffic Engineering and Quality of Service in Hybrid Software Defined Networks

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China Communications 2024年第2期21卷 96-121页

作者： Samiullah mehraban Rajesh Kumar Yadav IOT Lab Department of Computer Science&EngineeringDelhi Technological UniversityDelhi 110042India

For Future networks, many research projects have proposed different architectures around the globe;Software Defined Network(SDN) architectures, through separating Data and Control Layers, offer a crucial structure for it. With a worldwide view and centralized Control, the SDN network provides flexible and reliable network management that improves network throughput and increases link utilization. In addition, it supports an innovative flow scheduling system to help advance Traffic Engineering(TE). For Medium and large-scale networks migrating directly from a legacy network to an SDN Network seems more complicated & even impossible, as there are High potential challenges, including technical, financial, security, shortage of standards, and quality of service degradation challenges. These challenges cause the birth and pave the ground for Hybrid SDN networks, where SDN devices coexist with traditional network devices. This study explores a Hybrid SDN network’s Traffic Engineering and Quality of Services Issues. Quality of service is described by network characteristics such as latency, jitter, loss, bandwidth,and network link utilization, using industry standards and mechanisms in a Hybrid SDN Network. We have organized the related studies in a way that the Quality of Service may gain the most benefit from the concept of Hybrid SDN networks using different algorithms and mechanisms: Deep Reinforcement Learning(DRL), Heuristic algorithm, K path partition algorithm, Genetic algorithm, SOTE algorithm, ROAR method, and Routing Optimization with different optimization mechanisms that help to ensure high-quality performance in a Hybrid SDN Network.

关键词： DRL hSDN QoE QoS SDN TE

Quasi Three-Body Decay of D Meson

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Communications in Theoretical Physics 2018年第4期69卷 407-416页

作者： T.Estabar H.mehraban Physics Department Semnan University P.O. Box 35195-363 Semnan Iran

The aim of this work is to provide a phenomenological analysis of the contribution of D^0 meson to K*(892)~0π^+π^-(K*(892)~0-→π^+K^-), K^-π^+ω(ω-→π^+π^-π~0) and K^-π^+?(?(1020)-→ K^+K^-) quasi-three-body decays. The analysis of mentioned multi-body decays is such as to factorize into the three-body decay and several channels observed. Hadronic three-body decays receive both resonant and non-resonant contribution. Based on the factorization method, there are tree and emission annihilation diagrams for these decay modes. In the case of D^0 to vector pseudoscalar states appeared in factored terms, the matrix elements of the vector and axial vector currents between the D^0 and PV mesons can be computed by using D^(*+)pole. Considering the non-resonant and resonant amplitude in our computation,the theoretical values of the branching ratio are(9.78 ± 0.46) × 10^(-3),(2.74 ± 0.17) × 10^(-2), and(3.53 ± 0.23) × 10^(-5), while the experimental results of them are(9.9 ±2.3) × 10^(-3),(2.7 ± 0.5) × 10^(-2), and(4 ± 1.7) × 10^(-5) respectively. Comparing computational analysis values with experimental values show that our results are in approximately agreement with them.

关键词： three-body decay factorization method non-resonant contribution resonant contribution branching ratio

Approximate energies and thermal properties of a position-dependent mass charged particle under external magnetic fields

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Chinese Physics B 2017年第6期26卷 22-30页

作者： M Eshghi H mehraban S M Ikhdair Young Researchers and Elite Club Central Tehran BranchIslamic Azad UniversityTehranIran Faculty of Physics Semnan UniversitySemnanIran Department of Physics Faculty of ScienceAn-Najah National UniversityNablusWest BankPalestine Department of Electrical Engineering Near East UniversityNicosiaNorthern CyprusMersin 10Turkey

We solve the Schrodinger equation with a position-dependent mass（PDM） charged particle interacted via the superposition of the Morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharonov–Bohm（AB） flux fields. The nonrelativistic bound state energies together with their wave functions are calculated for two spatially-dependent mass distribution functions. We also study the thermal quantities of such a system. Further, the canonical formalism is used to compute various thermodynamic variables for second choosing mass by using the Gibbs formalism. We give plots for energy states as a function of various physical parameters. The behavior of the internal energy, specific heat, and entropy as functions of temperature and mass density parameter in the inverse-square mass case for different values of magnetic field are shown.

关键词： Schr?dinger equation Morse-plus-Coulomb potentials position-dependent mass distribution functions perpendicular magnetic and Aharonov–Bohm flux fields

Non-relativistic scattering amplitude for a new multi-parameter exponential-type potential

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Chinese Physics B 2016年第8期25卷 21-25页

作者： Yazarloo B H mehraban H Hassanabadi H Physics Department Semnan University Physics Department Shahrood University of Technology

In this paper, we study the scattering properties of s-wave Schrdinger equation for the multi-parameter potential,which can be reduced into four special cases for different values of potential parameters, i.e., Hulthn, Manning–Rosen,and Eckart potentials. We also obtain and investigate the scattering amplitudes of these special cases. Some numerical results are also obtained and reported.

关键词： scattering amplitude Schrodinger equation multi-parameter potential phase shifts cross section

Clinical value of intravesical prostatic protrusion in the evaluation and management of prostatic and other lower urinary tract diseases

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Asian Journal of Urology 2017年第3期4卷 174-180页

作者： Darab mehraban Tehran University of Medical Sciences TehranIran

Intravesical prostatic protrusion(IPP)has emerged as a new prostatic morphometric parameter of significance to aid the clinicians in various aspects of managing the patients with some diseases of the lower urinary tract and the *** include but may not be limited to its role in such conditions as:bladder outlet obstruction,trial without catheter,medical treatment effect,progression of lower urinary tract symptoms related to benign prostatic hypertrophy(LUTS/BPH),risk factor for bladder stone in BPH,overactive bladder,prostate carcinoma,and early urinary continence recovery after laparoscopic radical *** this review,I will try to summarize the different researchers’efforts on the potential practical application of this clinical *** is ever evolving to help us in the diagnosis and management of our ***,we as clinicians should contemplate their cost and possible suffering for the patient by wise and judicious utilization based on our clinical experience and *** seems to be one such promising clinical tool.

关键词： Intravesical prostatic protrusion Benign prostatic hypertrophy Diagnosis Treatment Prognosis Complications Prostatic adenocarcinoma Hydrodynamic simulation Fluid structural interaction

Eigen-spectra in the Dirac-attractive radial problem plus a tensor interaction under pseudospin and spin symmetry with the SUSY approach

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Chinese Physics B 2013年第10期22卷 112-118页

作者： S.Arbabi Moghadam H.mehraban M.Eshghi Young Researchers and Elite Club Central Tehran BranchIslamic Azad UniversityTehranIran Physics Department Faculty of SciencesSemnan UniversitySemnanIran Physics Department Imam Hossein Comprehensive UniversityTehranIran

We approximately solve the Dirac equation for attractive radial potential including a Coulomb-like tensor interaction under pseudospin and the spin symmetry limit for any arbitrary spin-orbit quantum number, by employing the supersymmetric （SUSY） quantum mechanics and supersymmetric shape invariance technique. We obtain the energy eigenvalue equation under the pseudospin and spin conditions. Some numerical results are compared with those obtained by the Nikiforove-Uvarov （NU） method.

关键词： Dirac equation attractive radial SUSY Coulomb-like tensor potential

Relativistic Bound and Scattering Amplitude of Spinless Particles in Modified Schioberg Plus Manning–Rosen Potentials

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Communications in Theoretical Physics 2017年第1期67卷 71-75页

作者： B.H.Yazarloo H.mehraban Physics Department Semnan UniversityP.O.Box 35195-363SemnanIran

By using an approximation for the centrifugal term, we study relativistic bound and scattering states of spin-zero particles in the presence of equal scalar and vector modified Schioberg plus Manning–Rosen potentials for any quantum numbers n and l. Energy eigenvalues and the scattering amplitude are calculated. Some special cases of the problem are also investigated.

关键词： modified Schioberg plus Manning–Rosen potentials Klein–Gordon equation bound state scattering state scattering amplitude

Quantitative risk of positive family history in developing colorectal cancer: A meta-analysis

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World Journal of Gastroenterology 2019年第30期25卷 4278-4291页

作者： Parsa mehraban Far Abdulaziz Alshahrani Mohammad Yaghoobi Division of Medicine Queen’s UniversityKingstonON K7L 3N6Canada Division of Gastroenterology McMaster UniversityHamiltonON L8S 4K1Canada The Farncombe Family Digestive Health Research Institute McMaster UniversityHamiltonON L8S 4K1Canada

BACKGROUND Positive family history is a risk factor for development of colorectal *** numerous studies on the topic,the absolute risk in patients with a positive family history remains unclear and therefore studies are lacking to validate non-invasive screening methods in individuals with positive family *** To quantify the risk of colorectal cancer in individuals with a positive family *** A comprehensive electronic literature search was performed using PubMed from January 1955 until November 2017,EMBASE from 1947 until 2018,and Cochrane Library without date *** independent reviewers conducted study selection,data extraction and quality assessment.A meta-analysis of Mantel-Haenzel relative risks was performed using the random effects ***-Ottawa scale was used to score the quality of selected *** plot and Egger’s regression test was performed to detect publication *** analysis was performed comparing Asian and non-Asian *** analyses were performed to rule out the effect of the timing of the study,overall quality,the main outcome and the effect of each individual study in overall *** Forty-six out of 3390 studies,including 906981 patients were included in the final analysis.41 of the included studies were case-control and 5 were cohort.A positive family history of colorectal cancer in first-degree relatives was associated with significantly increased risk of colorectal cancer with a relative risk of 1.87(95%CI:1.68-2.09;P<0.00001).Cochrane Q test was significant(P<0.00001,I2=90%).Egger’s regression test showed asymmetry in the funnel plot and therefore the Trim and Fill method was used which confirmed the validity of the *** was no difference between Asian versus non-Asian *** remained robust in sensitivity *** Individuals with a positive family history of colorectal cancer are 1.87 times more likely to develop colorectal cancer

关键词： Colorectal cancer Risk Family history

Bound States of (1+1)-dimensional Dirac Equation with Kink-like Vector Potential and Delta Interaction

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 1131-1140页

作者： M.ESHGHI H.mehraban Sameer M.IKHDAIR Yang Researchers and Elite Club Central Tehran BranchIslamic Azad University Faculty of Physics Semnan University Department of Electrical Engineering Near East University Department of Physics Faculty of ScienceAn-Najah National University

The relativistic problem of spin-1/2 fermions subject to vector hyperbolic （kink-like） potential （- tanh kx） is investigated by using the parametric Nikiforov-Uvarov method. The energy eigenvalue equation and the ... 详细信息

关键词： (1+1)-dimensional Dirac equation kink-like potential Rosen-Morse potential NU method