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Hybrid energy systems have attracted significant attention to supply the power requirements of stand-alone areas. Among different configurations, photovoltaic-diesel (PV/diesel) power generation systems are one of the most promising ones for their good performance. Owing to the complexity of the hybrid PV/diesel system, optimal balance between these two sources needs particular attention to find a good engineering solution. This paper focuses on optimal sizing of a PV/diesel power generation system by harmony search (HS) algorithm. Three new pitch adjustment mechanisms are introduced to enhance the diversification and intensification capabilities of HS. The results are compared with the results obtained by original HS, particle swarm optimization (PSO) and genetic algorithm (GA). Simulation results show that HS-II which focuses on intensification, finds more promising results than the other investigated methods. Moreover, hybridization of PV and diesel generator reduces the system costs and pollutant emissions. © 2017 Elsevier Ltd

Karimi-Maleh H.,Kerman Graduate University of Technology | Biparva P.,Sari University of Agricultural Sciences and Natural Resources | Hatami M.,Khorramshahr Marine Science and Technology University
Biosensors and Bioelectronics | Year: 2013

A carbon paste electrode (CPE) modified with (9, 10-dihydro-9, 10-ethanoanthracene-11, 12-dicarboximido)-4-ethylbenzene-1, 2-diol (DEDE) and NiO/CNTs nanocomposite was used for the sensitive voltammetric determination of cysteamine (CA), nicotinamide adenine dinucleotide (NADH) and folic acid (FA) for the first time. The synthesized materials were characterized with different methods such as XRD, cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV). The modified electrode exhibited a potent and persistent electron mediating behavior followed by well-separated oxidation peaks of CA, NADH and FA. The peak currents were linearly dependent on CA, NADH and FA concentrations using square wave voltammetry (SWV) method in the ranges of 0.01-250, 1.0-500, and 3.0-550μmolL-1, with detection limits of 0.007, 0.6, and 0.9μmolL-1, respectively. The modified electrode was used for the determination of CA, NADH and FA in biological and pharmaceutical samples. © 2013 Elsevier B.V.

Beitollahi H.,Kerman Graduate University of Technology | Mostafavi M.,Payame Noor University
Electroanalysis | Year: 2014

A novel carbon paste electrode modified with carbon nanotubes and 5-amino-2′-ethyl-biphenyl-2-ol (5AEB) was fabricated. The electrochemical study of the modified electrode, as well as its efficiency for electrocatalytic oxidation of levodopa (LD) and carbidopa (CD), is described. Cyclic voltammetry (CV) was used to investigate the redox properties of this modified electrode at various scan rates. The apparent charge transfer rate constant, ks, and transfer coefficient, a, for electron transfer between 5AEB and CPE were calculated as 17.3s-1 and 0.5, respectively. Square wave voltammetry (SWV) exhibits a linear dynamic range from 2.5×10-7 to 2.0×10-4M and a detection limit of 9.0×10-8M for LD. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mosaddegh E.,Kerman Graduate University of Technology
Ultrasonics Sonochemistry | Year: 2013

The nano eggshell powder (NESP) has been prepared by ultrasound irradiation and used as a novel and biodegradable catalyst with high catalytic activity and reusability in green synthesis of 2-aminochromenes via condensation of α- or β-phathol, malononitrile and aromatic aldehydes at 120 C under solvent-free conditions. The reaction proceeds to completion within 10-35 min in 91-98% yield. Nano eggshell catalyst was characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy and X-ray fluorescence, thermal gravimetric, surface area and elemental analyses. In addition, the catalytic activity and chemical structure of nano-sized eggshell were compared with pure CaCO3. © 2013 Elsevier B.V. All rights reserved.

Askarzadeh A.,Kerman Graduate University of Technology
International Journal of Hydrogen Energy | Year: 2013

Polarization curves of proton exchange membrane fuel cells (PEMFCs) are affected by various parameters. The relative importance and effect of each parameter on the polarization curve is different. This paper studies estimation of parameters with the most influence on the electrochemical model. In order to evaluate the obtained results, the model accuracy is compared with that model in which all the parameters are estimated. Because PEMFCs parameter estimation is a complex optimization problem, a recently invented nature-inspired algorithm, bird mating optimizer (BMO), is proposed. For this aim, two real systems, the SR-12 Modular PEM Generator and the Ballard Mark V FC, are considered. The obtained results show that when the whole parameters are estimated, the accuracy of the model increases. Also, BMO algorithm yields better results than the other studied methods in terms of precision and robustness. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Alizadeh M.,Kerman Graduate University of Technology | Bordbar S.,Kerman Graduate University of Technology
Corrosion Science | Year: 2013

In the present work, a novel heat treatment process was used to investigate the influence of microstructure alteration on the corrosion behavior of base metal (BM), heat affected zone (HAZ) and weld metal (WM) in welded pipe steel of grade API X70. The electrochemical impedance spectroscopy (EIS) measurements were carried out to study the protective properties of the corrosion product layer after 90. days immersion in a high-pH solution. The EIS results showed that, the corrosion resistance of HAZ and WM increased after heat treatment due to formation of fine and compact corrosion product layer with fewer defects. © 2013 Elsevier Ltd.

The importance of energy demand estimation stems from energy planning, formulating strategies and recommending energy policies. Most often, energy demand is mathematically formulated by socio-economic indicators. The challenging problem is to determine the optimal or near optimal weighting factors. Inspired by social behavior of bird flocking or fish schooling, PSO (particle swarm optimization) is a population-based search technique which has attracted significant attention to tackle the complexity of difficult optimization problems. This paper studies the performance of different PSO variants for estimating Iran's electricity demand. Seven PSO variants namely, original PSO, PSO-w (PSO with weighting factor), PSO-cf (PSO with constriction factor), PSO-rf (PSO with repulsion factor), PSO-vc (PSO with velocity control), CLPSO (comprehensive learning PSO) and a MPSO (modified PSO), are used to find the unknown weighting factors based on the data from 1982 to 2003. The validation process is then conducted by testing the optimized models by using the data from 2004 to 2009. It is seen that PSO-vc produces more promising results than the other variants, HS (harmony search) and ABSO (artificial bee swarm optimization) algorithms in terms of MAPE (mean absolute percentage error). This value is obtained 2.47 and 2.50 for the exponential and quadratic models, respectively. © 2014 Elsevier Ltd.

Safari H.,Kerman Graduate University of Technology | Karimpour M.R.,Kerman Graduate University of Technology
Physical Review Letters | Year: 2015

We present a formula for the body-assisted van der Waals interaction potential between two atoms, one or both being prepared in an excited energy eigenstate. The presence of an arbitrary arrangement for a material environment is taken into account via the Green function. The resulting formula supports one of two conflicting findings recorded. The consistency of our formula is investigated by applying it for the case of two atoms in free space and comparing the resulting expression with the one found from the limiting Casimir-Polder potential between an excited atom and a small dielectric sphere. © 2015 American Physical Society.

Askarzadeh A.,Kerman Graduate University of Technology
Solar Energy | Year: 2013

This paper tries to develop an efficient methodology for optimizing size of wind-photovoltaic hybrid energy systems. Since finding optimal size belongs to discrete optimization problems, optimization algorithm must be able to effectively handle this kind of problem. For this aim, a Discrete Harmony Search (DHS) algorithm is developed. The proposed methodology is easy to implement, can efficiently handle the discrete problem and can quickly find a good solution. The obtained results show that the proposed methodology finds promising results in less than one second. © 2013 Elsevier Ltd.

Askarzadeh A.,Kerman Graduate University of Technology
Solar Energy | Year: 2013

Optimum design of PV/wind hybrid system has become the main focus of many investigations. The ultimate aim of the optimum design is to determine the number of PV panels, wind turbines and batteries so that the total annual cost of the hybrid system subject to some constraints is minimized. The main motivation of this study is to develop a simple but efficient discrete optimization methodology for solving the optimum sizing problem. For this aim, the advantages of three well-known algorithms, namely, chaotic search (CS), harmony search (HS) and simulated annealing (SA), are merged and a novel discrete chaotic harmony search-based simulated annealing algorithm, named DCHSSA, is developed. The proposed methodology is used to find the optimum design of a PV/wind hybrid system. Simulation results indicate the superior performance of the DCHSSA algorithm. © 2013 Elsevier Ltd.

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