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Bahmani-Firouzi B.,Shiraz University | Farjah E.,Shiraz University | Azizipanah-Abarghooee R.,Islamic Azad University at Marvdasht
Energy | Year: 2013

Renewable energy resources such as wind power plants are playing an ever-increasing role in power generation. This paper extends the dynamic economic emission dispatch problem by incorporating wind power plant. This problem is a multi-objective optimization approach in which total electrical power generation costs and combustion emissions are simultaneously minimized over a short-term time span. A stochastic approach based on scenarios is suggested to model the uncertainty associated with hourly load and wind power forecasts. A roulette wheel technique on the basis of probability distribution functions of load and wind power is implemented to generate scenarios. As a result, the stochastic nature of the suggested problem is emancipated by decomposing it into a set of equivalent deterministic problem. An improved multi-objective particle swarm optimization algorithm is applied to obtain the best expected solutions for the proposed stochastic programming framework. To enhance the overall performance and effectiveness of the particle swarm optimization, a fuzzy adaptive technique, θ-search and self-adaptive learning strategy for velocity updating are used to tune the inertia weight factor and to escape from local optima, respectively. The suggested algorithm goes through the search space in the polar coordinates instead of the Cartesian one; whereby the feasible space is more compact. In order to evaluate the efficiency and feasibility of the suggested framework, it is applied to two test systems with small and large scale characteristics. © 2012 Elsevier Ltd.


Saadat H.,Islamic Azad University at Marvdasht
International Journal of Theoretical Physics | Year: 2011

In this article we investigate the relation between the temperature and density of the dark energy. We find that the temperature of the dark universe is proportional to the inverse of dark energy density. Also we discuss some values of the important parameters of the theory. © 2010 Springer Science+Business Media, LLC.


Saadat H.,Islamic Azad University at Marvdasht
International Journal of Theoretical Physics | Year: 2011

In this article we consider the cosmological model based on the holographic dark energy. We study dark energy density in Universe with arbitrary spatially curvature described by the Friedmann-Robertson-Walker metric. We use Chevallier-Polarski-Linder parametrization to specify dark energy density. © 2011 Springer Science+Business Media, LLC.


Esfandiari N.,Islamic Azad University at Marvdasht
Journal of Supercritical Fluids | Year: 2015

The solubility and bioavailability of pharmaceutical compounds are increased via size reduction. The conventional size reduction methods have some disadvantages. The pharmaceutical micronization with supercritical fluids (SCFs) techniques has been proposed. These methods overcome the disadvantages of conventional methods. Therefore, in this work, literature data analysis on the supercritical fluid micronization has been reviewed. The SC carbon dioxide is usually proposed. Micronization with supercritical fluids is classified based on the role of supercritical fluid in a process. Application of these methods for the pharmaceutical micronization has attracted interest in recent year because the micronized particles with narrow particle size distribution and no organic solvent are produced. These methods are rapid expansion of supercritical solutions (RESS) process, gas antisolvent (GAS) process, supercritical antisolvent (SAS) process, solution enhanced dispersion by supercritical (SEDS) process, aerosol solvent extraction system (ASES), supercritical fluid extraction of emulsions (SFEE), and particle from gas saturated solution (PGSS) process. © 2015 Elsevier B.V. All rights reserved.


Saadat H.,Islamic Azad University at Marvdasht
International Journal of Theoretical Physics | Year: 2012

In this paper we consider FRW bulk viscous cosmology in arbitrary space curvature. We extend recent work to the case of non-flat universe in arbitrary space dimension. We obtain Hubble expansion parameter for special cases and study bulk viscous coefficient and deceleration parameter. © 2011 Springer Science+Business Media, LLC.


Saadat H.,Islamic Azad University at Marvdasht
International Journal of Theoretical Physics | Year: 2012

In this paper, we consider holographic Ricci dark energy model, and by using general relativity equations obtain time-dependent density of the Universe. We show that the resulting density in independent of space curvature. © 2011 Springer Science+Business Media, LLC.


Bahmani-Firouzi B.,Islamic Azad University at Marvdasht | Azizipanah-Abarghooee R.,Islamic Azad University at Marvdasht
International Journal of Electrical Power and Energy Systems | Year: 2014

In recent years, due to large integration of Renewable Energy Sources (RESs) like wind turbine and photovoltaic unit into the Micro-Grid (MG), the necessity of Battery Energy Storage (BES) has increased dramatically. The BES has several benefits and advantages in the MG-based applications such as short term power supply, power quality improvement, facilitating integration of RES, ancillary service and arbitrage. This paper presents the cost-based formulation to determine the optimal size of the BES in the operation management of MG. Also, some restrictions, i.e. power capacity of Distributed Generators (DGs), power and energy capacity of BES, charge/discharge efficiency of BES, operating reserve and load demand satisfaction should be considered as well. The suggested problem is a complicated optimization problem, the complexity of which is increased by considering the above constraints. Therefore, a robust and strong optimization algorithm is required to solve it. Herein, this paper proposes a new evolutionary technique named improved bat algorithm that is used for developing corrective strategies and to perform least cost dispatches. The performance of the approach is evaluated by one grid-connected low voltage MG where the optimal size of BES is determined professionally. © 2013 Elsevier Ltd. All rights reserved.


Saadat H.,Islamic Azad University at Marvdasht
International Journal of Theoretical Physics | Year: 2012

In this paper we consider an interesting model of superfluid and use AdS/CFT correspondence to extract sound modes. We assume that dual picture of superfluid is the R-charged black hole with two equal charges. By using hydrodynamic variables of such a black hole we obtain first, second and fourth sound modes as a function of black hole charge. © 2012 Springer Science+Business Media, LLC.


Saadat H.,Islamic Azad University at Marvdasht
International Journal of Theoretical Physics | Year: 2012

In this paper we consider holographic dark energy model with interaction in the flat space-time with non-zero cosmological constant. We calculate cosmic scale factor and Hubble expansion parameter by using the time-dependent dark energy density. Then, we obtain phenomenological interaction between holographic dark energy and matter. We fixed our solution by using the observational data. © 2012 Springer Science+Business Media, LLC.


Azizipanah-Abarghooee R.,Islamic Azad University at Marvdasht
International Journal of Electrical Power and Energy Systems | Year: 2013

This paper presents a novel approach to depict the practical constraints of generator units such as reserve constraints, prohibited operating zones and valve-point effects in the optimal dynamic dispatch problem. Determining the power generation output of units at minimum total fuel cost a dynamic environment with ramp rate limits to satisfy load demand and transmission losses is too complicated and has a lot of local optima in its search space. In addition, the proposed problem has a non-linear, non-convex, non-smooth, multi-modal, non-separable, and non-differentiable nature. In order to overcome above problems a new hybrid technique, based on bacterial foraging and simplified swarm optimization algorithms combined with a new mutation operator and opposition-based initialization is proposed to restraint the premature convergence of the solutions. Therefore, the bacteria in chemo-tactic procedure are moved in short or long steps as well as swimming movements. Furthermore, to increase the diversity of the solution of the search space a novel self-adaptive mutation strategy which profits from four mutation rules is implemented. For more validation the simulation results are applied on four small, medium and large scale systems with 5-unit, 10-unit, 30-unit and 100-unit and compared with those of other methods in the area. © 2013 Elsevier Ltd. All rights reserved.

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