Time filter

Source Type

Nabati R.,Islamic Azad University at Hamadān | Nejad A.G.,Hamadan University of Technology | Yousefi A.,Islamic Azad University at Hamadān
2016 8th International Conference on Information and Knowledge Technology, IKT 2016 | Year: 2016

One of the most important challenges in social network models is dissimilarity of proposed models with real networks. In this article we proposed a new small world model generator based on binary trees that simulate family and human ties. In reality family such as father, children, and grandchildren makes a path between grandfather and grandchildren. We used this property to adopt effective parameters of proposed model with real networks. Proposed model implemented in Gephi analysis and visualization software and as the result the generated graph is compared with some of the recent models. © 2016 IEEE.

Esmi Jahromi M.,Islamic Azad University at Tehran | Ehsan M.,Sharif University of Technology | Fattahi Meyabadi A.,Hamadan University of Technology
International Journal of Electrical Power and Energy Systems | Year: 2012

This paper presents a dynamic multi objective model for distribution network expansion, considering the distributed generators (DGs) and network reinforcements. The proposed model simultaneously optimizes three objective functions namely, total cost, emission cost and technical satisfaction (voltage profile) by finding the optimal schemes of timing, sizing, placement and DG technologies in a long term planning period (dynamic planning). The importance of each objective function can be changed in the interactive steps. The calculation algorithm is based on Chaotic Local Search with Modified Honey Bee Mating Optimization (CLSMHBMO). The effectiveness of the proposed model and the calculation method are demonstrated through different studies and comparative analysis on an actual distribution network. © 2012 Elsevier Ltd. All rights reserved.

Faieghi M.R.,Hamadan University of Technology | Azimi S.M.,Hamadan University of Technology
UKSim2010 - UKSim 12th International Conference on Computer Modelling and Simulation | Year: 2010

The trapezoidal back-emf synchronous motor which is called brushless DC (BLDC) motor is receiving wide attention for industrial applications because of its high torque density, high efficiency and small size. This kind of electrical motors is a typical example of highly coupled, nonlinear systems. In the first part of this paper an intelligent agent based on Adaptive Neuro-Fuzzy Inference System (ANFIS) is developed to perform Non-linear Auto-Regressive Moving Average with eXogenous input (NARMAX) system identification of BLDC motor. At first we used exhaustive search technique to select the ANFIS inputs, and then by using Fuzzy C-Means (FCM) algorithm, an ANFIS has been performed to approximate the motor characteristics. In the second part, an optimized Proportional-Integral- Derivative (PID) controller has been developed. Particle Swarm Optimization (PSO) has been used as an optimization algorithm to tune the parameters of the controller. All steps simulated by MATLAB resulted in notable performance. © 2010 IEEE.

Meyabadi A.F.,Hamadan University of Technology | Ehsan M.,Sharif University of Technology
Journal of Intelligent and Fuzzy Systems | Year: 2013

This paper proposes a new technique to manage congestion in a short-run market model. The method consists of an iterative algorithm to search and apply a sequence of bilateral power exchanges among the generators that would optimally reduce and completely remove the congestions. A combination of fuzzy decision principle and sensitivity analysis is developed to choose the best exchange and AC load flow is used to apply it on the network in the iterations. The effectiveness of the proposed approach is illustrated in a case study on IEEE 118-bus system, and results are discussed in the paper in comparison with the mathematical and evolutionary-based optimization techniques. © 2013 - IOS Press and the authors. All rights reserved.

Rafiee Z.,Bu - Ali Sina University | Meyabadi A.F.,Hamadan University of Technology
International Journal of Power and Energy Conversion | Year: 2012

In power system, the application of the power system stabiliser (PSS) has been proved to overcome the stability of power system. It is necessary to determine the appropriate PSS parameters. In this paper, a new cost function is presented for the tuning of PSS parameters. Optimisation of PSS parameters has been done by particle swarm optimisation algorithm. The power plant system that is simulated in this paper is one machine to infinite bus system. The responses of the PSS tuned with PSO and conventional power system stabiliser (CPSS) are compared with together. Copyright © 2012 Inderscience Enterprises Ltd.

Medi B.,Hamadan University of Technology | Monzure-Khoda K.,Qatar University | Amanullah M.,Qatar University
Industrial and Engineering Chemistry Research | Year: 2015

This work presents experimental implementation of an improved single-column chromatographic (ISCC) separation process and its optimizing controller. A mixture of guaifenesin enantiomers has been used to evaluate the performance and integrity of (i) the ISCC process and its online monitoring system in open-loop experiments and (ii) the model predictive optimizing controller for closed-loop operation. The open-loop operation has been particularly aimed at assessing the accuracy and precision of the online monitoring system. In the closed-loop operation, the performance of the developed model predictive control (MPC) scheme has been tested for set point tracking and disturbance rejection with an objective function that reflects the process economics. The online optimal operating condition was also compared to the offline optimum condition obtained using a genetic algorithm. Results confirm that the optimizing controller is adequate to operate and maintain the ISCC process at an optimal operating point while fulfilling the product requirements. © 2015 American Chemical Society.

Modirrousta A.,Hamadan University of Technology | Sohrab M.,Malek-Ashtar University of Technology | Dehghan S.M.M.,Malek-Ashtar University of Technology
Transactions of the Institute of Measurement and Control | Year: 2016

In this paper, a solution for the problem of uncertainty presence in the estimated position of a target is indicated. The dynamic error of ground moving target tracking with special unknown bounded uncertainty has been described. To solve this problem, a class of the second-order sliding mode has been proposed. In order to increase the robustness of the proposed controller against unknown uncertainty, a set of adaptive rules has been added to the guidance law. New adaptive terms have been used to estimate the higher unknown bound of the uncertainty. The offered method, based on the sliding mode strategy, has reduced the chattering phenomena, which is harmful for the production of the command states. Finally, a fast adaptive guidance law has been added and its stability has been proved by the Lyapunov criterion. The designed adaptive fast guidance law improves the classical sliding mode control guidance law. Various simulations and comparison studies have been applied to verify the efficiency of the modified guidance law despite the disturbance and uncertainty. The results show that the uncertain terms have been compensated and the tracking position has been satisfied accurately. © SAGE Publications.

Modirrousta A.,Hamadan University of Technology | Khodabandeh M.,Hamadan University of Technology
2014 2nd RSI/ISM International Conference on Robotics and Mechatronics, ICRoM 2014 | Year: 2014

This paper proposes two different adaptive robust sliding mode controllers for attitude, altitude and position control of a quadrotor. First it proposes a backstepping non-singular terminal sliding mode control with adaptive algorithm which applied to the quadrotor for free chattering, finite time convergences and robust aims. In this control scheme instead of regular control input, the derivative of the control input is achieved from non-singular terminal second-layer sliding surface. And an adaptive tuning method is utilized to deal with the external disturbances whose upper bounds are not required to be known in advance in the inner loop. Second nonlinear disturbance observer based on integral sliding mode with adaptive gains is proposed for position control which is known as outer loop. Stability and robustness of the proposed controller are proved by using the classical Lyapunov criterion. The simulation results demonstrate the validation of the proposed control scheme. © 2014 IEEE.

Savari Z.,University of Kurdistan | Soltanian S.,University of Kurdistan | Soltanian S.,University of British Columbia | Noorbakhsh A.,University of Isfahan | And 4 more authors.
Sensors and Actuators, B: Chemical | Year: 2013

A novel, highly sensitive sensor for detection of persulfate (S 2O8 2-) is demonstrated by modification of carbon paste electrode (CPE) with nickel oxide nanowires (NiOx NWs) and neutral red (NR). Ni NWs are prepared by DC electrodeposition of Ni in the cylindrical pores of anodized aluminum oxide (AAO) templates. NWs are released, oxidized and immobilized with NR on the surface of CPE. Cyclic voltammetry studies demonstrate a pair of well-defined nearly reversible redox couples (E°′ = -0.2 V in a buffer solution pH 2.0) at a wide pH range of 1-12. The surface coverage and heterogeneous electron transfer rate constant of the adsorbed redox couple are 7.368 × 10-12 mol cm-2 and 7.9 s-1, respectively, indicating a high NR loading efficiency for NiOx NWs and efficient electron transfer between redox couple and the electrode. The modified CPE exhibits an excellent electrocatalytic activity for a S 2O8 2- reduction, with a measured k cat of ∼7.14 × 103 M-1 s -1. This catalytic reduction allows an amperometric detection of S2O8 2- at a potential of -0.2 V with detection limit of 30 nM, concentration calibration range of 0.1 μM to 12 mM and a linear sensitivity of 647.33 nA μM-1, respectively. © 2012 Elsevier B.V. All rights reserved.

Koohbor M.,University of Kurdistan | Soltanian S.,University of Kurdistan | Soltanian S.,University of British Columbia | Najafi M.,University of Kurdistan | And 2 more authors.
Materials Chemistry and Physics | Year: 2012

Highly ordered arrays of Co 1-xZn x (0 ≤ x ≤ 0.74) nanowires (NWs) with diameters of ∼35 nm and high length-to-diameter ratios (up to 150) were fabricated by co-electrodeposition of Co and Zn into pores of anodized aluminum oxide (AAO) templates. The Co and Zn contents of the NWs were adjusted by varying the ratio of Zn and Co ion concentrations in the electrolyte. The effect of the Zn content, electrodeposition conditions (frequency and pH) and annealing on the structural and magnetic properties (e.g., coercivity (Hc) and squareness (Sq)) of NW arrays were investigated using X-ray diffraction (XRD), scanning electron microscopy, electron diffraction, and alternating gradient force magnetometer (AGFM). XRD patterns reveal that an increase in the concentration of Zn ions of the electrolyte forces the hcp crystal structure of Co NWs to change into an amorphous phase, resulting in a significant reduction in Hc. It was found that the magnetic properties of NWs can be significantly improved by appropriate annealing process. The highest values for Hc (2050 Oe) and Sq (0.98) were obtained for NWs electrodeposited using 0.95/0.05 Co:Zn concentrations at 200 Hz and annealed at 575 °C. While the pH of electrolyte is found to have no significant effect on the structural and magnetic properties of the NW arrays, the electrodeposition frequency has considerable effects on the magnetic properties of the NW arrays. The changes in magnetic property of NWs are rooted in a competition between shape anisotropy and magnetocrystalline anisotropy in NWs. © 2011 Elsevier B.V. All rights reserved.

Loading Hamadan University of Technology collaborators
Loading Hamadan University of Technology collaborators