Islamic Azad University at Lahijan
Rasht, Iran

Islamic Azad University of Lahijan is a campus of Islamic Azad University system in Iran.The university was established in 1988 by some professors of Tehran University of Medical science include Dr. Mir Mozafar Maysoumi who was the first President of the university.So far 16000 students graduated from university. Wikipedia.

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Mahboub V.,Islamic Azad University at Lahijan | Sharifi M.A.,University of Tehran
Journal of Geodesy | Year: 2013

A weighted total least-squares (WTLS) approach with linear and quadratic constraints is developed. This method is according to the traditional Lagrange approach to optimize the target function of this problem. The WTLS and constrained total least-squares (CTLS) approach had been distinctively investigated, however, these two problems have not been simultaneously considered yet; furthermore, among the contributions on the CTLS problem, only Schaffrin and Felus considered linear and quadratic constraints together; nevertheless, in many practical examples, some elements of the design/coefficient matrix are fixed and should not be modified and this approach cannot deal with these cases. The main necessity of this research appears after the desirable property of the WTLS approach in preserving the structure of the design matrix was proven by Mahboub. In other words, currently, the WTLS approach is one of the most efficient methods for solving the so-called errors-in-variables model and an attempt for equipping it with constraints seems necessary. Also it is demonstrated that the additional constraints have a 'regularization role' for ill-conditioned problems and the unconstrained solution suffers from ill-conditioning effects which give it an added advantage over the unconstrained WTLS algorithm. Four geodetic applications indicate the significant of this problem in the presence of colored and white noise in the data. © 2012 Springer-Verlag Berlin Heidelberg.

Mehdipour S.H.,Islamic Azad University at Lahijan
Astrophysics and Space Science | Year: 2013

We study some features of entropic force approach in the presence of a noncommutative Schwarzschild-deSitter black hole. In this setup, there exists a similarity between the small and large scales. There are two finite cut-off in very short and long distances wherein the force and energy graph stop abruptly at those scales. We find that the existence of a deSitter core around the origin, induced by noncommutativity, in addition to a standard deSitter background at large scale may lead to a violation of the equivalence principle. Finally in order to directly observe the finite cut-off at short-scale gravity, caused by noncommutativity quantum fluctuations, we derive an effective gravitational constant. © 2013 Springer Science+Business Media Dordrecht.

Mehdipour S.H.,Islamic Azad University at Lahijan
International Journal of Modern Physics A | Year: 2010

We apply the tunneling process of charged massive particles through the quantum horizon of a ReissnerNordström black hole in a new noncommutative gravity scenario. In this model, the tunneling amplitude on account of noncommutativity influences in the context of coordinate coherent states is modified. Our calculation points out that the emission rate satisfies the first law of black hole thermodynamics and is consistent with an underlying unitary theory. © 2010 World Scientific Publishing Company.

Abdolahzadeh Ziabari A.,Islamic Azad University at Lahijan | Ghodsi F.E.,Guilan University
Journal of Luminescence | Year: 2013

Cu doped CdS nanocrystalline thin films were prepared by the sol-gel dip-coating method incorporated in polyethyleneglycol matrix. After heat treatment in air at 250 and 350 C, the prepared thin films were investigated by studying their structural, morphological, compositional, optical (linear and nonlinear) and photoluminescence properties. X-ray diffraction (XRD) results suggest that the samples are polycrystalline in nature with hexagonal crystal structure and the average grain size is in the range of 15-19 nm. The surface morphology of the films was examined by scanning electron microscopy (SEM). The results showed that the films consist of nanocrystalline grains included in the clusters with uniform coverage of the substrate surface. To examine the chemical composition of the films, the X-ray photoelectron spectra (XPS) of the composite films were measured. It was found that the transmittance and the band gap decreased totally as the Cu concentration/annealing temperature increased. The refractive index of the films was studied and the related dispersion was discussed in terms of the Wemple-Didomenico single oscillator model. The third-order nonlinear polarizability of the films was estimated through a semi-empirical relation based on single oscillator model and the results showed that the prepared films are proper to use as optical switch. For photoluminescence (PL) study, 200 and 365 nm excitation wavelengths were examined and compared together. The intensities of emission peaks for the prepared thin films varied with Cu doping/annealing temperature and the behaviors of different band peaks were discussed with giving reasons. © 2013 Elsevier B.V. All rights reserved.

Mahboub V.,Islamic Azad University at Lahijan
Studia Geophysica et Geodaetica | Year: 2014

A method for variance component estimation (VCE) in errors-in-variables (EIV) models is proposed, which leads to a novel rigorous total least-squares (TLS) approach. To achieve a realistic estimation of parameters, knowledge about the stochastic model, in addition to the functional model, is required. For an EIV model, the existing TLS techniques either do not consider the stochastic model at all or assume approximate models such as those with only one variance component. In contrast to such TLS techniques, the proposed method considers an unknown structure for the stochastic model in the adjustment of an EIV model. It simultaneously predicts the stochastic model and estimates the unknown parameters of the functional model. Moreover the method shows how an EIV model can support the Gauss-Helmert model in some cases. To make the VCE theory into EIV model more applicable, two simplified algorithms are also proposed. The proposed methods can be applied to linear regression and datum transformation. We apply these methods to these examples. In particular a 3-D non-linear close to identical similarity transformation is performed. Two simulation studies besides an experimental example give insight into the efficiency of the algorithms. © 2013 Institute of Geophysics of the ASCR, v.v.i.

Moradi-e-Rufchahi E.O.,Islamic Azad University at Lahijan
Chinese Chemical Letters | Year: 2010

In this study, 6-chloro-4-hydroxy-2-quinolone and 6-flouro-4-hydroxy-2-quinolone were synthesized from corresponding dianilides. These compounds were coupled with some diazotized aromatic amines to give the corresponding azo disperse dyes. The structures of the quinolone derivatives and new azo dyes were confirmed by UV-vis, FT-IR, 1H NMR and elemental analysis. © 2010 Enayat O'llah Moradi-e-Rufchahi.

Abdolahzadeh Ziabari A.,Islamic Azad University at Lahijan | Rozati S.M.,Guilan University
Physica B: Condensed Matter | Year: 2012

Contribution of band edge nonparabolicity to the charge carrier transport in degenerate n-type zinc oxide thin films has been investigated theoretically in order to understand the fundamental aspects of electron scattering in such thin films regardless of precise details of the preparation procedure. To conduct this, the theoretical evaluated results have been compared to the experimental values taken from literatures. The results indicate that the nonparabolicity (introducing through effective mass of charge carriers) has a strong effect on the total mobility of carriers in zinc oxide films so that a satisfactory agreement with experimental data is fulfilled. The dependence of nonparabolicity on bandgap shift is also discussed. Studying the optoelectronic properties of numerous moderately and heavily doped samples revealed that their optical bandgap has lower blueshift than the theoretical value obtained from the well-known Burstein-Moss effect. So, the observed bandgap shift was dependent on the carrier concentration and the total shift of bandgap was evaluated by combining the Burstein-Moss and bandgap narrowing effects. Two different cases were also examined; parabolic and nonparabolic (modified) Burstein-Moss effects. The results show that the modified Burstein-Moss effect leads to great agreement with experimental data. © 2012 Elsevier B.V.

Mehdipour S.H.,Islamic Azad University at Lahijan
Astrophysics and Space Science | Year: 2014

We present some well-known energy-momentum complexes and evaluate the gravitational energy associated with static spherically symmetric spacetimes. In fact, the energy distribution of the aforementioned gravitational background that is contained in a two-sphere of radius r shows that a test particle situated at a finite distance r experiences the gravitational field of the effective gravitational mass. In addition, we apply Verlinde's entropic gravity to find the emergent gravitational energy on static spherically symmetric screens. In this setup, we find that the energy distribution in the prescription of Møller is similar to the energy derived from the emergent gravity, while other prescriptions give the different results. This result may confirm the argument of Lessner who argues that Møller's definition of energy is a powerful concept of energy in General Relativity. © 2014 Springer Science+Business Media Dordrecht.

Mehdipour S.H.,Islamic Azad University at Lahijan
Canadian Journal of Physics | Year: 2012

Using the noncommutative geometry inspired Vaidya metric obtained in terms of coordinate coherent states and also utilizing the generalized uncertainty principle (GUP), we show that the nonthermal nature of the Hawking spectrum leads to Planck-scale nonthermal correlations between emitted modes of evaporation. Our analysis thus exhibits that owing to self-gravitational effects plus noncommutativity and GUP influences, information can emerge in the form of Planck-scale correlated emissions from the black hole. © 2012 Published by NRC Research Press.

Mehdipour S.H.,Islamic Azad University at Lahijan
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

In the context of a noncommutative model of coordinate coherent states, we present a Schwarzschild-like metric for a Vaidya solution instead of the standard Eddington-Finkelstein metric. This leads to the appearance of an exact (t-r) dependent case of the metric. We analyze the resulting metric in three possible causal structures. In this setup, we find a zero remnant mass in the long-time limit, i.e. an instable black hole remnant. We also study the tunneling process across the quantum horizon of such a Vaidya black hole. The tunneling probability including the time-dependent part is obtained by using the tunneling method proposed by Parikh and Wilczek in terms of the noncommutative parameter σ. After that, we calculate the entropy associated to this noncommutative black hole solution. However, the corrections are fundamentally trifling; one could respect this as a consequence of quantum inspection at the level of semiclassical quantum gravity. © 2010 The American Physical Society.

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