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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.

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.

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.

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.

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