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East Azerbaijan, Iran

Eftekhari-Sis B.,Islamic Azad University at Maragheh | Akbari A.,Islamic Azad University at Maragheh | Amirabedi M.,Islamic Azad University at Ajabshir
Chemistry of Heterocyclic Compounds | Year: 2011

New N-alkyl(aryl)-2,4-diaryl-1H-pyrrol-3-ol derivatives have been synthesized in moderate to good yields in a novel and efficient process by aldol reaction of 1-(4-methoxyphenyl)propan-2-ones with phenylglyoxal in the presence of DABCO in water, followed by Paal-Knorr reaction with amines in the presence of a catalytic amount of p-TSA in toluene at reflux. © 2011 Springer Science+Business Media, Inc. Source

Kisi O.,Erciyes University | Shiri J.,University of Tabriz | Nikoofar B.,Islamic Azad University at Ajabshir
Computers and Geosciences | Year: 2012

Accurate prediction of lake-level variations is important for planning, design, construction, and operation of lakeshore structures and also in the management of freshwater lakes for water supply purposes. In the present paper, three artificial intelligence approaches, namely artificial neural networks (ANNs), adaptive-neuro-fuzzy inference system (ANFIS), and gene expression programming (GEP), were applied to forecast daily lake-level variations up to 3-day ahead time intervals. The measurements at the Lake Iznik in Western Turkey, for the period of January 1961-December 1982, were used for training, testing, and validating the employed models. The results obtained by the GEP approach indicated that it performs better than ANFIS and ANNs in predicting lake-level variations. A comparison was also made between these artificial intelligence approaches and convenient autoregressive moving average (ARMA) models, which demonstrated the superiority of GEP, ANFIS, and ANN models over ARMA models. © 2011 Elsevier Ltd. Source

Beigbabaei B.,Islamic Azad University at Ajabshir
Advances in Environmental Biology | Year: 2014

Background: Extensive need of human to energy resources and his endeavor to access unending energy resources were always regarded as one of the most essential problems of human life and his inveterate willing. Human consistently look for applying of energy in industries. He used wind power to move sailboats and windmills. At present, it seems necessary to deal with wind power considering the above-mentioned cases and its economical justifiability in comparison with other modern energies. Objective: The purpose of this study was evaluating climate and climatic factors (wind) at residential areas (Rasht). Results: Natural ventilation is one of the best and most inexpensive ventilation methods realized through creating indoor natural air. In traditional architecture, natural ventilation was regarded as one of the most important parts of buildings design. Nowadays, optimal use of wind power is extremely underestimated due to density of adjacent buildings. Rasht is located in a humid climate. Since its humidity is about 100% almost all over the year, creating draught between buildings and their inside is of special importance. Considering importance of the subject, the present study deals with wind flow status of some residential blocks located at Golsar district of Rasht in order to offer approaches to optimally use airflow through evaluating indoor and outdoor draught. External and internal properties and campus effect are of important factors in evaluating these residential buildings. Conclusion: The research uses field and documentary studies and provides some results about better productivity of the energy. © 2013 AENSI Publisher All rights reserved. Source

Rahmani A.,Islamic Azad University at Ahar | Eslami G.,Islamic Azad University at Ahar | Soleimani R.,Islamic Azad University at Ajabshir
Life Science Journal | Year: 2013

A Turbine blade, which is a main high temperature component of a gas-turbine for power generation does not tolerate the existence of cracks as it rotates at a high speed. Consequently, the development of an analytical method to evaluate the remaining life for crack initiation is required. The accuracy of remaining life evaluation by an analytical method largely depends on inelastic constitutive equations expressing on a creep-fatigue life evaluation method using such equations to estimate the remaining life for crack initiation. Therefore, in this paper, we studied creep-fatigue damage mechanism of gas turbine blades which is capable to describe inelastic behavior of the material and the damage mechanism. For this purpose we use Thermo-Mechanical Fatigue (TMF) life prediction models take into account the interaction between fatigue and creep at varying temperatures. Source

Ghanbari A.,University of Tabriz | Solaimani R.,Islamic Azad University at Tabriz | Rahmani A.,Islamic Azad University at Ajabshir | Tabatabaie F.,Islamic Azad University at Tabriz
Life Science Journal | Year: 2013

Grasping and manipulation of objects, as well as the capability interacting safely with the environment (possibly including also humans), is a fundamental task for a humanoid robot. In order to tackle these issues a great effort has been put for over two decades to develop robot hands or mechanisms emulating the grasping capabilities of a human. However, grasping and manipulation control also rely the availability of suitable contact and force feedback. In this article being inspired by biological samples, we have proceeded to designing and simulating fivefingered robotic hand which has the capability of touch sensing. Thus in this paper, to achieve this goal, the degree of freedom of each fingers has been calculated, Heartenberg- Dynavit parameters' has been exploited. Afterward each fingers as a 3rd series robot has been modeled. Then using Lagrange method we calculated each joint torque and dynamic equation separately and considering non-linear manner of equations we solved them using Newton- Raphson numerical approach. Finally we modeled a robotic hand by using Solid Works and Visual Nastran engineering softwares. Dynamic and kinematic analysis results of this hand including linear and angular acceleration, linear and angular velocity and each finger joint spatial position and Torque in ratio of time was calculated. Moreover each finger movement was simulated in Matlab soft ware and in order to make sure of results, imitating human hand function, we made an experimental model of hand being able to grasp things. Obtained results showed that there is an acceptable accordance among modeling results performed in Nastran software, simulation results performed in Matlab and experimental conclusions. Source

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