Islamic Azad University at Damavand
Damavand, Iran

Islamic Azad University of Damavand is a campus of Islamic Azad University system in Iran. has been established in 2002 with two major fields.This branch, now, has 54 fields – majors and more than 12000 students in Bachelor and master level, located in the east of Tehran, is a significant branch of technical and engineering departments in the country. Wikipedia.

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Response of sandwich beam with carbon nanotube reinforced composite (CNTRC) face sheets and soft core subjected to the action of an impacting mass based on the Extended High Order Sandwich Panel Theory (EHSAPT) is first analyzed. Distribution of fibers through the thickness of the face sheets could be uniform or functionally graded (FG). Contact force between the impactor and the beam is obtained using the conventional Hertz law. The field equations are derived via the Ritz based applied to the total energy of the system. The solution is obtained in the time domain by implementing the well-known Runge–Kutta method. After examining the validity of the present solution, the effects of distribution of Carbon Nanotubes (CNTs), nanotube volume fraction, core-to-face sheet thickness ratio, initial velocity of the impactor and the impactor mass are studied in detail. Finally, it is concluded that, the highest peak contact force and the lowest indentation of the top face sheet belong to the sandwich beam with V distribution figure of face sheet, followed by the UD and Λ-ones, respectively. Also, numerical results reveal that employing FG-CNTs in face sheets has a prominent role on impact response of the sandwich panel with soft core. © 2017 Elsevier Masson SAS

Zangeneh A.,Islamic Azad University at Damavand | Rahimi-Kian A.,University of Tehran
Energy | Year: 2011

To determine the optimal size, location and also the proper technology of distributed generation (DG) units in distribution systems, a static fuzzy multiobjective model is proposed in this paper. The proposed model can concurrently optimize a number of conflicting and competing objective functions including economic, technical and environmental attributes. The economic function is the profit of a distribution company (DisCo) from selling the DG output power to its customers. The contribution of this model is the consideration of some DG marginal revenues in the economic function. Inclusion of marginal revenues would not only reduce the investment risks of DG technologies, but also would enable the optimal penetration of DG units. The proposed DG planning framework considers various DG technologies such as photovoltaic (PV), wind turbine (WT), fuel cell (FC), micro-turbine (MT), gas turbine (GT) and diesel engine (DE). The system uncertainties (including those for the energy demand, energy price and DG technologies operating and investment costs) are modeled using fuzzy numbers. The numerical case studies have been carried out using the IEEE 37-node distribution test system to demonstrate the performance of the proposed DG planning model. © 2011.

Asemi S.R.,Islamic Azad University at Damavand | Farajpour A.,Islamic Azad University at Tehran
Physica E: Low-Dimensional Systems and Nanostructures | Year: 2014

This article deals with the axisymmetric vibration properties of circular single-layered graphene sheet embedded in a polymer matrix under thermo-mechanical loading. Both surface and nonlocal effects are taken into account. To this end, Gurtin-Murdoch continuum elasticity in conjunction with the nonlocal elasticity theory is used to develop a modified continuum plate model for free vibration analysis of the nanoplates. The governing equations are derived by decoupling the nonlocal constitutive equations of Eringen theory in the polar coordinate. Galerkin×.

Gheshlaghi B.,Islamic Azad University at Damavand | Hasheminejad S.M.,Iran University of Science and Technology
Applied Physics Letters | Year: 2012

The Timoshenko [S. S. Rao, Vibration of Continuous Systems (Wiley, New York, 2007)] beam model is used to derive the differential equations governing the free vibrations of thick nanowires (NWs) with dissipative surface stress effects. The natural frequencies are calculated as functions of NW length as well as thickness-to-length ratio, with the effects of dissipation, transverse shear deformation, and rotary inertia being included. The effects of latter two parameters are significant especially for higher modes of vibration and shorter NWs and are different from what is naively expected based on elementary mechanics for some specific dimensions. The results are also compared with the previous study using Euler-Bernoulli beam theory. © 2012 American Institute of Physics.

Soroudi A.,Islamic Azad University at Damavand | Ehsan M.,Sharif University of Technology
IEEE Transactions on Smart Grid | Year: 2013

This paper presents the application of information gap decision theory (IGDT) to help the distribution network operators (DNOs) in choosing the supplying resources for meeting the demand of their customers. The three main energy resources are pool market, distributed generations (DGs), and the bilateral contracts. In deregulated environment, the DNO is faced with many uncertainties associated to the mentioned resources which may not have enough information about their nature and behaviors. In such cases, the classical methods like probabilistic methods or fuzzy methods are not applicable for uncertainty modeling because they need some information about the uncertainty behaviors like probability distribution function (PDF) or their membership functions. In this paper, a decision making framework is proposed based on IGDT model to solve this problem. The uncertain parameters considered here, are as follows: price of electricity in pool market and demand of each bus. The robust strategy of DNO is determined to hedge him against the risk of increasing the total cost beyond what it is willing to pay. The effectiveness of the proposed tool is assessed and demonstrated by applying it on a large distribution network. © 2010-2012 IEEE.

Ilbeygi M.,Islamic Azad University at Damavand | Shah-Hosseini H.,Shahid Beheshti University
Engineering Applications of Artificial Intelligence | Year: 2012

Emotion recognition plays an effective and important role in HumanComputer Interaction (HCI). Recently, various approaches to emotion recognition have been proposed in the literature, but they do not provide a powerful approach to recognize emotions from Partially Occluded Facial Images. In this paper, we propose a new method for Emotion Recognition from Facial Expression using Fuzzy Inference System (FIS). This novel method is even able to recognize emotions from Partially Occluded Facial Images. Moreover, this research describes new algorithms for facial feature extraction that demonstrate satisfactory performance and precision. In addition, one of the main factors that have an important influence on the final precision of fuzzy inference systems is the membership function parameters. Therefore, we use a Genetic Algorithm for parameter-tuning of the membership functions. Experimental results report an average precision rate of 93.96% for Emotion Recognition of six basic emotions, which is so promising. © 2011 Elsevier Ltd. All rights reserved.

Javadi-Moghaddam J.,Islamic Azad University at Damavand | Bagheri A.,Guilan University
Expert Systems with Applications | Year: 2010

This study presents an adaptive neuro-fuzzy sliding-mode-based genetic algorithm (ANFSGA) control system for a remotely operated vehicle (ROV) with four degrees of freedom (DOF)s. In many applications, ROVs will need to be capable of maneuvering to any given point, following object, and to be controllable from the surface. Therefore, an ANFSGA control system is introduced for tracking control of the ROV to achieve a high precision position control. Since the dynamic of ROVs are highly nonlinear and time varying, an ANFSGA control system is investigated according to direction-based genetic algorithm (GA) with the spirit of sliding mode control and adaptive neuro-fuzzy sliding mode (ANFS) based evolutionary procedure. In this way, on-line learning ability is employed to deal with the parametric uncertainty and disturbance by adjusting the ANFS inference parameters. In this proposed controller a GA control system is utilized to be the major controller, and stability can be indirectly insured by the concept of sliding mode control system without strict constraints and detailed system knowledge. © 2009 Elsevier Ltd. All rights reserved.

Ghasemzadeh H.,Islamic Azad University at Damavand
2014 Iranian Conference on Intelligent Systems, ICIS 2014 | Year: 2014

Puzzle solving is the art of pattern recognition which has found many applications in different areas such as restoration and reconstruction of archeological findings, repairing of broken objects, solving jigsaw puzzles, molecular docking problem, etc. There are two inherent problems in solving a general jigsaw puzzle; one is how to search through possible arrangements efficiently. The other one is devising some piece matching technique. To our best knowledge, current literature lacks a thorough investigation of the first problem. This paper investigates this problem in depth. Furthermore, different metaheuristic approaches to solve this problem are explored. © 2014 IEEE.

Zabihiyeganeh M.,Tehran University of Medical Sciences | Jahed A.,Islamic Azad University at Damavand | Nojomi M.,Tehran University of Medical Sciences
Clinical Endocrinology | Year: 2013

Objective Vitamin D deficiency is a worldwide health problem. Usual supplements are inadequate for prevention of hypovitaminosis D, and much higher doses are needed for its treatment. This study was designed to compare the efficacy and practicality of high-dose intramuscular and oral cholecalciferol in treatment of hypovitaminosis D and to evaluate durability of the effect of each remedy. Design Ninety-two patients with hypovitaminosis D [serum 25(OH) D level < 75 nmol/l] were enrolled in a randomised clinical trial. Participants were randomly assigned to receive 300 000 IU cholecalciferol, either intramuscularly as a single injection or orally in six divided doses during 3 months period. Serum 25(OH) D level was measured at baseline and at 3 and 6 months. Results Both treatment regimens significantly increased the serum 25(OH)D level. Delta change in serum 25(OH) D level from baseline (presented as mean ± SEM) at month 3 was significantly higher in oral than injection group (90 ± 11·2 and 58·8 ± 8·9 nmol/l, respectively, P = 0·03); but was similar at 6th month intervention (52·1 ± 7·6 and 62·2 ± 6·7 nmol/l, respectively, P = 0·32). There was a marginally significant trend in favour of oral group in the proportion of cases attained vitamin D adequacy at 6th month (P = 0·06); but still 15% of all patients remained at < 50 nmol/l. Conclusion Both regimens were considerably effective, safe and practical in treating hypovitaminosis D. Although we revealed superiority of oral route, at least at early short time, the way of treatment may depend on the patient's choice, compliance and availability of various forms of the drug in any regions. © 2012 Blackwell Publishing Ltd.

Sadeghi A.,Islamic Azad University at Damavand
ZAMM Zeitschrift fur Angewandte Mathematik und Mechanik | Year: 2012

The resonant frequency of flexural vibration for a V shaped atomic force microscope (AFM) cantilever has been investigated using the Timoshenko beam theory. Generally, three different regions are considered for V shaped cantilevers, one region with constant cross section and height and two double tapered regions. In this paper, the effects of the different parameters on the non-dimensional frequency and sensitivity to the contact stiffness have been studied. The differential quadrature method (DQM) is applied to solve the nonlinear differential equations of motion. The results show that the resonant frequency decreases when Timoshenko beam parameter or cantilever thickness increases and high order modes are more sensitive to it. The first frequency is sensitive only in the lower range of contact stiffness, but the high order frequencies are sensitive to the contact stiffness in a larger range. It is possible to increase the range of sensitivity to the contact stiffness by increasing the width ratio for the first mode. By increasing both height and breadth taper ratios the resonant frequency increases. The resonant frequency is sensitive to the width ratio and by increasing this ratio, the resonant frequency decreases, but critical contact stiffness increases and finally the variations of the height and breadth taper ratios and width ratio are affected on the sensitivity to the contact stiffness. We show that the sensitivity to the contact stiffness can be increased by the variations of height taper ratio and this matter has never been investigated formerly. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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