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Tehran, Iran

Islamic Azad University - Garmsar Branch is a branch of Iran's Islamic Azad Universities. It is situated in the city of Garmsar 82 kilometers southeast of Tehran. Wikipedia.

Nasehi M.,Islamic Azad University at Garmsar
Basic and Clinical Neuroscience

Introduction: The plethora of studies indicated that there is a cross talk relationship between harmaline and serotonergic (5-HT) system on cognitive and non-cognitive behaviors. Thus, the purpose of this study is to assess the effects of hippocampal 5-HT4 receptor on memory acquisition deficit induced by harmaline. Methods: Harmaline was injected peritoneally, while 5-HT4 receptor agonist (RS67333) and antagonist (RS23597-190) were injected intra-hippocampal. A single-trial step-down passive avoidance, open field and tail flick tasks were used for measurement of memory, locomotor activity and pain responses, respectively. Results: The data revealed that pre-training injection of higher dose of harmaline (1 mg/kg), RS67333 (0.5 ng/mouse) and RS23597-190 (0.5 ng/mouse) decreased memory acquisition process in the adult mice. Moreover, concurrent pre-training administration of subthreshold dose of RS67333 (0.005 ng/mouse) or RS23597-190 (0.005 ng/mouse) with subthreshold dose of harmaline (0.5 mg/kg, i.p.) intensify impairment of memory acquisition. All above interventions did not change locomotion and tail flick behaviors. Discussion: The results demonstrated that the synergistic effect between both hippocampal 5-HT4 receptor agonist and antagonist with impairment of memory acquisition induced by harmaline, indicating a modulatory effect for hippocampal 5HT4 receptor on Harmaline induced amnesia. Source

Salehipour A.,Islamic Azad University at Garmsar | Modarres M.,Sharif University of Technology | Moslemi Naeni L.,Sharif University of Technology
Computers and Operations Research

Aircraft landing problem is to assign an airport's runways to the arrival aircrafts as well as to schedule the landing time of these aircrafts. In this paper, first a mixed integer goal programming model is developed. Then, due to the complexity of the problem, which is NP-hard, we design a hybrid meta-heuristic applying simulated annealing framework. The computational results show that the proposed algorithm can obtain the optimal solution for instances up to 100 aircrafts, and also it is capable of finding very high quality and comparable solutions for the problems with up to 500 aircrafts and 5 runways in a short time. © 2012 Elsevier Ltd. All rights reserved. Source

Heydari-doostabad H.,Semnan University | Keypour R.,Semnan University | Khalghani M.R.,Islamic Azad University at Mashhad | Khooban M.H.,Islamic Azad University at Garmsar
Solar Energy

This work presents a Maximum Power Point Tracking (MPPT) based on analyzing the output characteristics of PV array under uniform irradiance and partial shading conditions. In order to carry out MPPT in PV panels, under partial shading conditions a method based on Extremum Seeking Control (ESC) is introduced. In contrast with classic ESC, in this method the double of dithering signal frequency is not used, consequently PV output power has a ripple of a lower frequency. Also the drop which occurs when MPPT system starts to operate in classic ESC method is minimized in this paper. The ESC approach for MPPT in this paper uses a series combination of a Low Pass Filter (LPF) and a High Pass Filter (HPF). These two filters act as a Band Pass Filter (BPF) and let a specific frequency of input power which includes the derivative of PV with respect to its voltage pass through. Finally, the system does not operate in local optimal points for efficient point will be global. The algorithm adds partial shadow judging conditions in ESC method. The system runs the variable step ESC method to realize MPPT when photovoltaic array is under uniform irradiance. Under Partial Shading Condition (PSC), the control method can eliminate the interference of local maximum power point (MPP) to make 23 the PV array running at global MPP. In addition, unlike other methods, the proposed MPPT operates on the global MPPs. The proposed MPP tracker does not add any extra complexity compared to the classical ones. However, it increases significantly the efficiency of the PV installation under PSC. We will show that under uniform irradiance, the proposed MPPT leads to faster performances than classical approaches. © 2013. Source

Khooban M.H.,Islamic Azad University at Garmsar | Soltanpour M.R.,Iran University of Science and Technology
Journal of Intelligent and Fuzzy Systems

This paper provides an optimal controlling approach for a class of nonlinear systems with structured and unstructured uncertainties using fuzzy sliding mode control. First known dynamics of the system are eliminated through feedback linearization and then optimal fuzzy sliding mode controller is designed using an intelligent fuzzy controller based on Sugeno-Type structure. The proposed controller is optimized by a novel heuristic algorithm namely Particle Swarm Optimization with random inertia Weight (RNW-PSO). In order to handle, the uncertainties Lyapunov method is used. There are no signs of the undesired chattering phenomenon in the proposed method. The globally asymptotic stability of the closed-loop system is mathematically proved. Finally, this control method is applied to the inverted pendulum system as a case study. Simulation results show desirability of the system performance. © 2013-IOS Press and the authors. All rights reserved. Source

This paper addresses the design of a robust Lyapunov-based controller for flexible-joint electrically driven robots considering to voltage as control input. The proposed approach is related to the key role of electrical subsystem of the motors, thus is free from mechanical subsystem of the actuator dynamics, considered here as unmodeled dynamics. The main contribution of this paper is to prove that the closed-loop system composed by full nonlinear actuated robot dynamics and the proposed controller is BIBO stable, while actuator/link position errors are uniformly ultimately bounded stable in agreement with Lyapunov’s direct method in any finite region of the state space. It also forms a constructive and conservative algorithm for suitable choice of gains in PID controller. The analytical studies as well as experimental results produced using MATLAB/SIMULINK external mode control on a flexible-joint electrically driven robot demonstrate high performance of the proposed control schemes. © 2016 Springer Science+Business Media Dordrecht Source

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