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Arezoomand M.,Islamic Azad University at Majlesi | Taeri B.,Isfahan University of Technology
Match | Year: 2013

In this paper the first and the second Zagreb indices of generalized hierarchical product of graphs, which is generalization of standard hierarchical and Cartesian product of graphs, is computed. As a consequence we compute the Zagreb indices of some chemical graphs.

Majdzadeh-Ardakani K.,Islamic Azad University at Majlesi | Nazari B.,Isfahan University of Technology
Composites Science and Technology | Year: 2010

Thermoplastic starch/poly(vinyl alcohol) (PVOH)/clay nanocomposites, exhibiting the intercalated and exfoliated structures, were prepared via melt extrusion method. The effects of clay cation, water, PVOH and clay contents on clay intercalation and mechanical properties of nanocomposites were investigated. The experiments were carried out according to the Taguchi experimental design method. Montmorillonite (MMT) with three types of cation or modifier (Na+, alkyl ammonium ion, and citric acid) was examined. The prepared nanocomposites with modified montmorillonite indicated a mechanical improvement in the properties in comparison with pristine MMT. It was also observed that increases in tensile strength and modulus would be attained for nanocomposite samples with 10%, 5% and 4% (by weight) of water, PVOH and clay loading, respectively. The clay intercalation was examined by X-ray diffraction (XRD) patterns. The chemical structure and morphology of the optimum sample was also probed by FTIR spectroscopy and transmission electron microscopy (TEM). © 2010 Elsevier Ltd.

Razmjooy N.,Islamic Azad University at Majlesi | Mousavi B.S.,Islamic Azad University at Zahedan | Soleymani F.,Islamic Azad University at Zahedan
Computers and Mathematics with Applications | Year: 2012

Detection of external defects on potatoes is the most important technology in the realization of automatic potato sorting stations. This paper presents a hierarchical grading method applied to the potatoes. In this work a potato defect detection combining with size sorting system using the machine vision will be proposed. This work also will focus on the mathematics methods used in automation with a particular emphasis on the issues associated with designing, implementing and using classification algorithms to solve equations. In the first step, a simple size sorting based on mathematical binarization is described, and the second step is to segment the defects; to do this, color based classifiers are used. All the detection standards for this work are referenced from the United States Agriculture Department, and Canadian Food Industries. Results show that we have a high accuracy in both size sorting and classification. Experimental results show that support vector machines have very high accuracy and speed between classifiers for defect detection. © 2011 Elsevier Ltd. All rights reserved.

Banitaba S.H.,Islamic Azad University at Majlesi | Safari J.,University of Kashan | Khalili S.D.,Islamic Azad University at Najafabad
Ultrasonics Sonochemistry | Year: 2013

A green and simple approach to assembling of 2-amino-4,8-dihydropyrano[3,2- b]pyran-3-carbonitrile scaffolds via three-component reaction of kojic acid, malononitrile, and aromatic aldehydes in aqueous media under ultrasound irradiation is described. The combinatorial synthesis was achieved for this methodology with applying ultrasound irradiation while making use of water as green solvent. In comparison to conventional methods, experimental simplicity, good functional group tolerance, excellent yields, short routine, and selectivity without the need for a transition metal or base catalyst are prominent features of this green procedure. © 2012 Elsevier B.V. All rights reserved.

Taheri Otaqsara S.M.,Islamic Azad University at Majlesi
EPJ Applied Physics | Year: 2011

Use of microorganism as a novel and eco-friendly strategy to production of nanomaterials is an important aspect of modern nanotechnology. Biosynthesis of quasi-spherical silver nanoparticles (Ag-NPs) has been investigated using Pseudomonas aeruginosa. We observe that silver (Ag +) ions when exposed to P. aeruginosa biomass are reduced in solution, thereby leading to the formation of Ag-NPs. Quasi-spherical shape and nearly well distribution and FCC crystal structure of Ag-NPs were confirmed by XRD pattern, STM and TEM micrographs. UV-Vis spectra show a surface plasmon resonance (SPR) band at ~ 435 nm. © EDP Sciences, 2011.

A novel pure-hardware design of LMS-based adaptive FIR filter core is proposed which is highly efficient in FPGA area/resource utilization and speed. Unlike HW/SW co-design and other pure-hardware methods, the required area/resource is reduced while keeping the speed in an appropriate level by taking advantage of finite state machine (FSM) and using internal block-rams (BRAM). This model because of being completely general (device independent), gives the ability of implementation on different FPGA brands and thus, is suitable for embedded systems, system-onprogrammable-chip (SoPC) and network-on-chip (NoC) applications.

Abedi A.,Islamic Azad University at Majlesi
Energy Procedia | Year: 2012

Energy supply to Iran requires the substitution of an energy model based on fossil by one based on renewable energy sources. The building sector, about 40% of total annual energy consumption, has an important share in energy demand in Iran. Iran as a Middle Eastern country has recently begun to use renewable energies. Solar energy, because of its availability and large number of sunny days in this country, is mostly concentrated. In this paper vented thermal storage wall that is used for heating of Isfahan buildings, Central of IRAN, are studied. The heating loads for a residential building which has about 800m2 floor area at four floor are calculated. Then the vented thermal storage wall are designed and the amount of annual energy saving is calculated. It is shown that more than 60 percent of winter energy consumption will saved by using this system. © 2011 Published by Elsevier Ltd.

Taheri Otaqsara S.M.,Islamic Azad University at Majlesi
EPJ Applied Physics | Year: 2011

Co2+ doped ZnO nanoparticles (NPs) using PEG as a capping agent were prepared by colloidal wet-chemical method. The structure, morphology and characteristics of as-prepared samples were investigated. X-ray diffraction patterns studies revealed wurtzite crystal phase. STM-TEM micrographs show a spherical shape and nearly well distribution with an average particle size of ~15-20 nm. UV-VIS spectra show the presence of exciton peak at 349 nm which can be effectively tuned versus cobalt doping and PEG concentration. PL studies were done under the excitation of 347 nm, which exhibited a UV (~386 nm) and visible (blue-orange) emission peak because of free-exciton recombination and oxygen vacancy. © EDP Sciences, 2011.

Esfandiari E.,Islamic Azad University at Majlesi | Mariun N.B.,University Putra Malaysia
IEEE Transactions on Industrial Electronics | Year: 2013

This paper provides experimental results for a 2.5-kW 47-level prototype of the switch-ladder multilevel inverter including the following: input and output voltage and current waveforms under resistive and inductive loads, efficiency, total harmonic distortion, voltage stresses across the switches, behavior of the system under fault condition, and no-load power dissipation. The most important advantage of this inverter is that only four switches conduct in each interval in low frequency. This matter, beside the elimination of switching losses, has made this inverter an efficient choice with 97% peak efficiency. The ability to continue working with open-circuit modules is another advantage of the inverter. Furthermore, some important factors behind the unreliability and inefficiency of inverters have been improved, including the following: low duty cycle of conducting switches, staircase voltage stresses across switches with low-voltage steppes, line switching frequency results in low temperature of switches, possibility of removing low-pass filters, and independence to capacitors. The inverter is proposed to be an advantageous choice in low-voltage stand-alone photovoltaic applications. © 1982-2012 IEEE.

Emami H.,Islamic Azad University at Majlesi
IEEE Microwave and Wireless Components Letters | Year: 2015

A broadband frequency measurement system capable of measuring both frequency and amplitude of an RF signal with-31 dBm sensitivity and 100 MHz accuracy over 40 MHz to 40 GHz range is practically demosntrated. The amplitude independence was achieved via employing two orthogonal measurements and the high sensitivity was obtained by utilization of the lock-in amplification technique. © 2015 IEEE.

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