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Journal of Central South University 2018年第3期25卷 461-472页

作者： Saeed Lotfan Reza Fathi Young researchers and elite club Tabriz Branch Islamic Azad University

Nonlocal continuum mechanics is a popular growing theory for investigating the dynamic behavior of Carbon nanotubes(CNTs).Estimating the nonlocal constant is a crucial step in mathematical modeling of CNTs vibration behavior based on this ***,in this study a vibration-based nonlocal parameter estimation technique,which can be competitive because of its lower instrumentation and data analysis costs,is *** this end,the nonlocal models of the CNT by using the linear and nonlinear theories are ***,time response of the CNT to impulsive force is derived by solving the governing equations *** using these time responses the parametric model of the CNT is constructed via the autoregressive moving average(ARMA)*** appropriate ARMA parameters,which are chosen by an introduced feature reduction technique,are considered features to identify the value of the nonlocal *** this regard,a multi-layer perceptron(MLP)network has been trained to construct the complex relation between the ARMA parameters and the nonlocal *** training the MLP,based on the assumed linear and nonlinear models,the ability of the proposed method is evaluated and it is shown that the nonlocal parameter can be estimated with high accuracy in the presence/absence of nonlinearity.

关键词： nonlocal theory nonlocal parameter estimation autoregressive moving average artificial neural network feature reduction

Total Pairwise Quantum Correlation and Entanglement in a Mixed-Three-Spin Ising-XY Model with Added Dzyaloshinskii-Moriya Interaction under Decoherence

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Chinese Physics Letters 2016年第9期33卷 5-9页

作者： H.A.Zad Young researchers and elite club Mashhad BranchIslamic Azad University

We investigate the behavior of geometric global quantum discord （GGQD） and concurrence （C） between half- spins of a mixed-three-spin （1/2, 1, 1/2） system with the Ising-XY model for which spins （1, 1/2） have the Ising interaction and half-spins （1/2, 1/2） have both XY and the Dzyaloshinskii Moriya interactions together, under the decoherence action. A single-ion anisotropy property with coefficient ζ is assumed for the spin-integer. This system which includes an analytical Hamiltonian is considered at the front of an external homogeneous magnetic field B in thermal equilibrium. Finally, we compare GGQD and C and express some interesting phase flip reactions of the total quantum correlation and pairwise entanglement between spins （1/2, 1/2）. Generally, we conclude that the concurrence and GGQD have different behaviors under the phase flip channel.

关键词： of is in for Total Pairwise Quantum Correlation and Entanglement in a Mixed-Three-Spin Ising-XY Model with Added Dzyaloshinskii-Moriya Interaction under Decoherence with

Influence of Non-Maxwellian Particles on Dust Acoustic Waves in a Dusty Magnetized Plasma

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Communications in Theoretical Physics 2013年第11期60卷 615-622页

作者： M.Nouri Kadijani H.Zareamoghaddam Young researchers and elite club Kashmar Branch Islamic Azad University

In this paper an investigation into dust acoustic sofitary waves （DASWs） in the presence of superthermM electrons and ions in a magnetized plasma with cold dust gains and trapped electrons is discussed. The dynamic of both electrons and ions is simulated by the generalized Lorentzian （κ） distribution function （DF）. The dust grains are cold and their dynamics are studied by hydrodynamic equations. The basic set of fluid equations is reduced to modified Korteweg-de Vries （mKdV） equation using Reductive Perturbation Theory （RPT）. Two types of solitary waves, fast and slow dust acoustic soliton （DAS） exist in this plasma. Caiculations reveal that compressive solitary structures are possibly propagated in the plasma where dust grains are negatively （or positively） charged. The properties of DASs are also investigated numerically.

关键词： dust acoustic soliton magnetized plasma superthermal electrons and ions trapped electrons

Developing a Support Vector Machine Based QSPR Model to Predict Gas-to-Benzene Solvation Enthalpy of Organic Compounds

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物理化学学报 2017年第5期33卷 918-926页

作者： GOLMOHAMMADI Hassan DASHTBOZORGI Zahra KHOOSHECHIN Sajad Young researchers and elite club Yadegar-e-Imam Khomeini (RAH) Shahr-e-Rey Branch Islamic Azad University Young researchers and elite club Central Tehran Branch Islamic Azad University

The purpose of this paper is to present a novel way to building quantitative structure-property relationship(QSPR) models for predicting the gas-to-benzene solvation enthalpy(ΔHSolv) of 158 organic compounds based on molecular descriptors calculated from the structure alone. Different kinds of descriptors were calculated for each compounds using dragon package. The variable selection technique of enhanced replacement method(ERM) was employed to select optimal subset of descriptors. Our investigation reveals that the dependence of physico-chemical properties on solvation enthalpy is a nonlinear observable fact and that ERM method is unable to model the solvation enthalpy accurately. The standard error value of prediction set for support vector machine(SVM) is 1.681 kJ ? mol^(-1) while it is 4.624 kJ ? mol^(-1) for ERM. The results established that the calculated ΔHSolvvalues by SVM were in good agreement with the experimental ones, and the performances of the SVM models were superior to those obtained by ERM one. This indicates that SVM can be used as an alternative modeling tool for QSPR studies.

关键词：数量的结构-财产关系气体-到-苯媒合焓描述符提高了复位成本折旧法支承矢量机器

Phase Control of Transient Optical Properties of Double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams

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Chinese Physics Letters 2018年第2期35卷 29-33页

作者： J.Shiri F.Shahi M.R.Mehmannavaz L.Shahrassai Young researchers and elite club Tabriz BranchIslamic Azad University Department of Atomic and Molecular Physics University of Tabriz Young researchers and elite club Mashhad BranchIslamic Azad University

We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot *** show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser *** and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching *** estimated range is between 5-8 ps for subluminal to superluminal light propagation.

关键词： Phase Control of Transient Optical Properties of Double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams QDs

Orbital electronic heat capacity of hydrogenated monolayer and bilayer graphene

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Chinese Physics B 2017年第2期26卷 375-381页

作者： Mohsen Yarmohammadi Young researchers and elite club Kermanshah Branch Islamic Azad University Kermanshah Ira

The tight-binding Harrison model and Green＇s function approach have been utilized in order to investigate the contribution of hybridized orbitals in the electronic density of states（DOS） and electronic heat capacity（EHC） for four hydrogenated structures, including monolayer chair-like, table-like, bilayer AA- and finally AB-stacked graphene. After hydrogenation, monolayer graphene and bilayer graphene are behave as semiconducting systems owning a wide direct band gap and this means that all orbitals have several states around the Fermi level. The energy gap in DOS and Schottky anomaly in EHC curves of these structures are compared together illustrating the maximum and minimum band gaps are appear for monolayer chair-like and bilayer AA-stacked graphane, respectively. In spite of these, our findings show that the maximum and minimum values of Schottky anomaly appear for hydrogenated bilayer AA-stacked and monolayer table-like configurations, respectively.

关键词： hydrogenated monolayer and bilayer graphene Harrison model electronic heat capacity density of states Green's function

Generating capacity adequacy evaluation of large-scale, grid-connected photovoltaic systems

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Frontiers in Energy 2016年第3期10卷 308-318页

作者： Amir AHADI Seyed Mohsen MIRYOUSEFI AVAL Hosein HAYATI Young researchers and elite club Ardabil Branch Islamic Azad University Ardabil *** Iran

Large-scale, grid-connected photovoltaic sys- tems have become an essential part of modem electric power distribution systems. In this paper, a novel approach based on the Markov method has been proposed to investigate the effects of large-scale, grid-connected photovoltaic systems on the reliability of bulk power systems. The proposed method serves as an applicable tool to estimate performance （e.g., energy yield and capacity） as well as reliability indices. The Markov method frame- work has been incorporated with the＇ multi-state models to develop energy states of the photovoltaic systems in order to quantify the effects of the photovoltaic systems on the power system adequacy. Such analysis assists planners to make adequate decisions based on the economical expectations as well as to ensure the recovery of the investment costs over time. The failure states of the components of photovoltaic systems have been considered to evaluate the sensitivity analysis and the adequacy indices including loss of load expectation, and expected energy not supplied. Moreover, the impacts of transitions between failures on the reliability calculations as well as on the long- term operation of the photovoltaic systems have been illustrated. Simulation results on the Roy Billinton test system has been shown to illustrate the procedure of the proposed frame work and evaluate the reliability benefits of using large-scale, grid-connected photovoltaic system on the bulk electric power systems. The proposed method can be easily extended to estimate the operating and maintenance costs for the financial planning of the photovoltaic system projects.

关键词： adequacy assessment Markov method large-scale grid-connected photovoltaic(PV) systems long-termoperation

Multiple Quantum Coherences(MQ) NMR and Entanglement Dynamics in the Mixed-Three-Spin XXX Heisenberg Model with Single-Ion Anisotropy

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Communications in Theoretical Physics 2016年第12期65卷 629-637页

作者： Hamid Arian Zad Young researchers and elite club Mashhad Branch Islamic Azad University

We analytically investigate Multiple Quantum(MQ) NMR dynamics in a mixed-three-spin(1/2,1,1/2)system with XXX Heisenberg model at the front of an external homogeneous magnetic field B. A single-ion anisotropy property ζ is considered for the spin-1. The intensities dependence of MQ NMR coherences on their orders(zeroth and second orders) for two pairs of spins(1,1/2) and(1/2,1/2) of the favorite tripartite system are obtained. It is also investigated dynamics of the pairwise quantum entanglement for the bipartite(sub)systems(1,1/2) and(1/2,1/2)permanently coupled by, respectively, coupling constants J_1 and J_2, by means of concurrence and fidelity. Then, some straightforward comparisons are done between these quantities and the intensities of MQ NMR coherences and ultimately some interesting results are reported. We also show that the time evolution of MQ coherences based on the reduced density matrix of the pair spins(1,1/2) is closely connected with the dynamics of the pairwise entanglement. Finally, we prove that one can introduce MQ coherence of the zeroth order corresponds to the pair spins(1,1/2) as an entanglement witness at some special time intervals.

关键词： multiple quantum coherence single-ion anisotropy concurrence entanglement witness

Reliability evaluation of future photovoltaic systems with smart operation strategy

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Frontiers in Energy 2016年第2期10卷 125-135页

作者： Amir AHADI Hosein HAYATI SeyedMohsen MIRYOUSEFI AVAL Young researchers and elite club Ardabil Branch Islamic AzadUniversity Ardabil *** Iran

This paper investigates a new operation strategy for photovoltaic （PV） systems, which improves the overall reliability of the system as a result of the improvement in the reliability of the critical components. First, a mathematical model is proposed using the fault tree analysis （FTA） to estimate the reliability of the PV systems in order to find the suitable maintenance strategies. The implementations demonstrate that it is essential to employ smart maintenance plans and monitor the identified most critical components of PV systems. Then, an innovative analytical method based on the Markov process is presented to model smart operation plans in PV systems. The impact of smart operation strategy on the PV systems is then evaluated. The objective of this paper is to develop plans for improving the reliability of PV systems. A series of case studies have been conducted to demonstrate the importance of smart operation well as the applicability and method. strategies for PV systems as feasibility of the proposed

关键词： smart operation strategy renewable energy,fault tree analysis (FTA) Markov model

A novel method for reliability and risk evaluation of wind energy conversion systems considering wind speed correlation

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Frontiers in Energy 2016年第1期10卷 46-56页

作者： Seyed Mohsen MIRYOUSEFI AVAL Amir AHADI Hosein HAYATI Young researchers and elite club Ardabil Branch Islamic AzadUniversity Ardabil Iran

This paper investigates an analytical approach for the reliability modeling of doubly fed induction generator （DFIG） wind turbines. At present, to the best of the authors＇ knowledge, wind speed and wind turbine generator outage have not been addressed simultaneously. In this paper, a novel methodology based on the Weibull- Markov method is proposed for evaluating the probabil- istic reliability of the bulk electric power systems, including DFIG wind turbines, considering wind speed and wind turbine generator outage. The proposed model is presented in terms of appropriate wind speed modeling as well as capacity outage probability table （COPT）, considering component failures of the wind turbine generators. Based on the proposed method, the COPT of the wind farm has been developed and utilized on the IEEE RBTS to estimate the well-known reliability and sensitive indices. The simulation results reveal the importance of inclusion of wind turbine generator outage as well as wind speed in the reliability assessment of the wind farms. Moreover, the proposed method reduces the complexity of using analytical methods and provides an accurate reliability model for the wind turbines. Furthermore, several case studies are considered to demonstrate the effectiveness of the proposed method in practical applications.

关键词： doubly-fed induction generator (DFIG) com- posite system adequacy assessment wind speed correlation