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Sanikhani H.,Islamic Azad University at Tabriz | Kisi O.,Canik Basari University
Water Resources Management | Year: 2012

This paper demonstrates the application of two different adaptive neuro-fuzzy (ANFIS) techniques for the estimation of monthly streamflows. In the first part of the study, two different ANFIS models, namely ANFIS with grid partition (ANFIS-GP) and ANFIS with sub clustering (ANFIS-SC), were used in one-month ahead streamflow forecasting and the results were evaluated. Monthly flow data from two stations, the Besiri Station on the Garzan Stream and the Baykan Station on the Bitlis Stream in the Firat-Dicle Basin of Turkey were used in the study. The effect of periodicity on the model's forecasting performance was also investigated. In the second part of the study, the performance of the ANFIS techniques was tested for streamflow estimation using data from the nearby river. The results indicated that the performance of the ANFIS-SC model was slightly better than the ANFIS-GP model in streamflow forecasting. © 2012 Springer Science+Business Media B.V.

Pashazadeh H.,Islamic Azad University at Tabriz | Teimournezhad J.,University of Tehran
Materials and Design | Year: 2014

The objective of this study was to develop a numerical model for the prediction of temperature distributions, effective plastic strain distributions, and especially material flow in Friction Stir Welding of copper plates. DEFORM-3D was used by incorporating the Arbitrary Lagrangian Eulerian (ALE) formulation. Three-dimensional results of the material flow pattern extracted using the point tracking are in good agreement with the experiment. It was shown that the main part of material flow occurs near the top surface. Material near the top surface at the behind of tool stretches from retreating side towards advancing side, leads to non-symmetrical shape of the stir zone. The stir zone shape in FSW of copper alloys, predicted by simulation, does not lean completely towards any sides of welding line. © 2013 Elsevier Ltd.

Hanifian S.,Islamic Azad University at Tabriz | Khani S.,Tabriz University of Medical Sciences
International Journal of Food Microbiology | Year: 2012

To determine the prevalence of virulent Yersinia enterocolitica, 554 samples consisting of 354 bulk raw milks and 200 traditional cheeses were collected from different parts of Eastern-Azerbaijan province, during a 23-month period from 2008 to 2010. The occurrence of virulent strains of Y. enterocolitica in samples enriched in peptone sorbitol bile broth (PSBB) was evaluated via the detection of attachment invasion locus (ail) gene by PCR. The viability of virulent Y. enterocolitica in the PCR-positive samples was tested using conventional culture method and the isolates were confirmed by the second-phase ail-PCR. According to the results, 8.66% of total samples including 7.62% of bulk raw milks and 10.5% of raw milk cheeses were found ail-positive by PCR method; subsequently Y. enterocolitica was isolated by the culture method and confirmed by the second phase ail-PCR in 2.88% of total samples including 2.26% of raw milks and 4% of cheese samples. It was concluded that, a sample enrichment followed by ail-PCR was more sensitive and robust to detect and distinguish the virulent strains of Y. enterocolitica compared to the conventional culture method. © 2012 Elsevier B.V.

Mehmannavaz M.R.,Islamic Azad University at Mashhad | Sattari H.,Islamic Azad University at Tabriz
Laser Physics Letters | Year: 2015

We propose a model for a quintuple coupled quantum dot system based on a GaAs/AlGaAs heterostructure. Then, we analyze the optical bistability (OB) and optical multistability (OM) behaviours and transition between the regimes at a wavelength of λ = 1.550 μm. We take the benefit of consecutive and parallel interdot tunnelling and an incoherent pumping field for electrical and even optical control of the processes. It is shown that OB, OM and transition between them can be accomplished and controlled by adjusting the rate of the inter-dot tunnellings (electrical bias), probe wavelength detuning and rate of the optical incoherent pumping field. By proper choice of the controlling parameters, the bistable hysteresis loop becomes narrower, which makes it easier for the cavity field to reach saturation. We interpret the OB and OM behaviours by discussing the absorption of the active medium. We also investigate switching time between the two stable states when the output field jumps from a lower branch to an upper branch. Such a controllable OB/OM and transition between them in multiple QD molecules at a wavelength of 1.550 μm, may provide some new possibilities for technological applications in optoelectronics, solid-state quantum information science and systems dealing with signal processing. © 2015 Astro Ltd.

Souri A.,Islamic Azad University at Tabriz | Jafari Navimipour N.,Islamic Azad University at Tabriz
Expert Systems with Applications | Year: 2014

Grid computing is the federation of resources from multiple locations to facilitate resource sharing and problem solving over the Internet. The challenge of finding services or resources in Grid environments has recently been the subject of many papers and researches. These researches and papers evaluate their approaches only by simulation and experiments. Therefore, it is possible that some part of the state space of the problem is not analyzed and checked well. To overcome this defect, model checking as an automatic technique for the verification of the systems is a suitable solution. In this paper, an adopted type of resource discovery approach to address multi-attribute and range queries has been presented. Unlike the papers in this scope, this paper decouple resource discovery behavior model to data gathering, discovery and control behavior. Also it facilitates the mapping process between three behaviors by means of the formal verification approach based on Binary Decision Diagram (BDD). The formal approach extracts the expected properties of resource discovery approach from control behavior in the form of CTL and LTL temporal logic formulas, and verifies the properties in data gathering and discovery behaviors comprehensively. Moreover, analyzing and evaluating the logical problems such as soundness, completeness, and consistency of the considered resource discovery approach is provided. To implement the behavior models of resource discovery approach the ArgoUML tool and the NuSMV model checker are employed. The results show that the adopted resource discovery approach can discovers multi-attribute and range queries very fast and detects logical problems such as soundness, completeness, and consistency. © 2013 Elsevier Ltd. All rights reserved.

Vahid B.,Islamic Azad University at Tabriz | Khataee A.,University of Tabriz
Electrochimica Acta | Year: 2013

In this research work, a photoassisted electrochemical system under recirculation mode and with UV irradiation was designed for treatment of C.I. Acid Blue 92 (AB92) as a model anionic azo dye in aqueous solution. Degradation experiments were carried out with boron-doped diamond (BDD) anode and carbon nanotubes-polytetrafluoroethylene (CNTs-PTFE) cathode in the presence of sulfate as an electrolyte. A comparative study of AB92 degradation by photolysis, electrochemical oxidation and photoassisted electrochemical processes after 45 min of treatment demonstrated that degradation efficiency was 27.89, 37.65 and 95.86%, respectively. Experimental data revealed that the degradation rate of AB92 in all of the processes obeyed pseudo-first-order kinetics and application of photoassisted electrochemical system reduced electrical energy per order (EEO), considerably. Degradation efficiency of photoassisted electrochemical process enhanced by increasing applied current and flow rate values, but vice versa trend was observed for initial dye concentration and an optimum amount of 6 was obtained for initial pH. The TOC measurement results demonstrated that 93.24% of organic substrates were mineralized after 120 min of photoassisted electrochemical process and GC-Mass analysis was performed for identification of degradation intermediates. © 2012 Elsevier Ltd. All rights reserved.

This work, describes synthesis and in vitro evaluation of new acrylic-type polymeric prodrugs containing mesalazine, as colon targeted drug delivery systems. First, mesalazine reacted with formic acid, and the obtained material was reacted with 2-hydroxypropyl methacrylat in the presence of 1,1-carbonyldiimidazole to produce methacryloyloxypropyl 5-amino salicylate. The resulted acrylic-derivative of mesalazine was then polymerized with various acrylic monomers by free radical solution polymerization, utlizing azobisisobutyronitrile as an initiator at 70±2°C. The obtained polymer-drug conjugates were characterized by FT-IR, 1 H-NMR, elemental analysis, gel permeation chromatography, and differential scanning calorimetery techniques. The release studies were performed into dialysis bags by hydrolysis buffered solutions at 37°C. Detection of hydrolysis by UV spectrophotometer at free drug λmax (300 nm for pH 1; 339 nm for pH 7 and 8) in selected intervals showed that the mesalazine can be released by selective hydrolysis of the ester bond at the side of drug moiety. The release profiles indicated that the hydrophobicity of polymers and the pH value of the hydrolysis media have strongly effects on the hydrolytic behavior of the polymeric prodrugs.

Navimipour N.J.,Islamic Azad University at Tabriz
Expert Systems with Applications | Year: 2015

Expert Cloud as a new class of Cloud computing systems enables its users to request the skill, knowledge and expertise of people without any information of their location by employing Internet infrastructures and Cloud computing concepts. One of the most important service in Expert Cloud is to search trustworthy peoples in order to benefit from their knowledge and skills. In this paper we propose a new and applicable method for Trustworthy Human Resource Discovery (THRD) in Expert Cloud by introducing a resource discovery and trust evaluating method, implement the proposed method by using ASP.Net and SQL in Expert Cloud; verify the structures and compositions of THRD by describing the behavioral models and state diagrams; define a Kripke structure with marked states to provide the formal relationship between the expanded model and the original state diagram structures; define the expected properties of the structures and compositions of THRD by means of temporal logic languages; and implement the proposed model by NuSMV model checker. The results show that the proposed method can discover trustworthy people efficiently and is sound, complete, reachable, fair, deadlock-free and consistent. © 2015 Elsevier Ltd.

Hanifian S.,Islamic Azad University at Tabriz
Letters in Applied Microbiology | Year: 2014

Mycobacterium avium subsp. paratuberculosis (Map) is considered as a potential public health threat due to its possible association with Crohn's disease in humans. This study aimed to investigate the survival of Map in ultra-filtered white (UFW) cheese, with special reference to the effect of initial inoculum level, addition of starter culture and salt concentration. Behaviour of Map was monitored during the storage of UFW cheese using F57-quantitative real-time PCR and culture assay. According to the results, higher inoculum level prolongs Map persistence in UFW cheese. Furthermore, the addition of starter culture was found as the main restrictive parameter affecting the survival of Map in UFW cheese. Meanwhile, salt concentration did not accelerate Map inactivation. It was concluded that UFW cheese has potential to support the survival of Map. © 2014 The Society for Applied Microbiology.

Razagifard P.,Islamic Azad University at Tabriz
Journal of Computer Assisted Learning | Year: 2013

This paper reports on a study investigating the potential effect of synchronous and asynchronous text-based computer-mediated communication (CMC) on oral fluency development of second-language (L2) learners. Sixty-three intermediate learners of English were randomly assigned to one of three groups (two experimental groups and one control group), each consisting of 21 participants. The participants in the experimental groups completed four communicative tasks under two different instructional environments: synchronous text-based CMC environment and asynchronous text-based CMC environment. The average length of pauses, the articulation rate, the fluent-run, the phonation-time ratio and the speaking rate served as dependent variables. The study found that the participants in synchronous CMC group improved their L2 oral fluency significantly compared with their peers in the other two groups. The results also revealed the students in asynchronous CMC group obtained higher mean scores than those in the control group, although the differences between groups were not statistically significant. © 2012 Blackwell Publishing Ltd.

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