• XML

    isc pubmed crossref medra doaj doaj
  • List of Articles


      • Open Access Article

        1 - Mechanical System Modelling of Robot Dynamics Using a Mass/Pulley Model
        The well-known electro-mechanical analogy that equates current, voltage, resistance, inductance and capacitance to force, velocity, damping, spring constant and mass has a shortcoming in that mass can only be used to simulate a capacitor which has one terminal connected More
        The well-known electro-mechanical analogy that equates current, voltage, resistance, inductance and capacitance to force, velocity, damping, spring constant and mass has a shortcoming in that mass can only be used to simulate a capacitor which has one terminal connected to ground. A new model that was previously proposed by the authors that combines a mass with a pulley (MP) is shown to simulate a capacitor in the general case. This new MP model is used to model the off-diagonal elements of a mass matrix so that devices whose effective mass is coupled between more than one actuator can be represented by a mechanical system diagram that is topographically parallel to its equivalent electric circuit model. Specific examples of this technique are presented to demonstrate how a mechanical model can be derived for both a serial and a parallel robot with both two and three degrees of freedom. The technique, however, is extensible to any number of degrees of freedom. Manuscript profile
      • Open Access Article

        2 - Design of A Self-Tuning Adaptive Power System Stabilizer
        Power system stabilizers (PSSs) must be capable of providing appropriate stabilization signals over abroad range of operating conditions and disturbances. The main idea of this paper is changing aclassic PSS (CPSS) to an adaptive PSS using genetic algorithm. This new ge More
        Power system stabilizers (PSSs) must be capable of providing appropriate stabilization signals over abroad range of operating conditions and disturbances. The main idea of this paper is changing aclassic PSS (CPSS) to an adaptive PSS using genetic algorithm. This new genetic algorithm based onadaptive PSS (GAPSS) improves power system damping, considerably. The controller design issue isformulated as an optimization problem that is solved by GA to identify PSS parameters in variousoperating conditions. Numerical simulation studies have been done on a modified model of IEEEsecond benchmark. The consequence of these studies shows that, the performance of the suggestedgenetic algorithm based adaptive PSS in damping of electromechanical oscillations of power system isbetter than CPSS. Manuscript profile
      • Open Access Article

        3 - Design and Simulation 4-Channel Demultiplexer Based on Photonic Crystals Ring Resonators
        In this paper, a new design of demultiplexer based on two-dimensional photonic crystal ringresonator is proposed. The structure is made of a hexagonal lattice of silicon rods with therefractive index 3.46 in coefficient of air with refractive index 1. The transmission e More
        In this paper, a new design of demultiplexer based on two-dimensional photonic crystal ringresonator is proposed. The structure is made of a hexagonal lattice of silicon rods with therefractive index 3.46 in coefficient of air with refractive index 1. The transmission efficiencyand Quality factor for our proposed demultiplexer, respectively, are more than 65% and1600. The normalized transmission spectra of the photonic crystal ring resonator are takenusing Two-dimensional (2D) Finite Difference Time Domain (FDTD) method. The photonicband gap is calculated by Plane Wave Expansion (PWE) method. Manuscript profile
      • Open Access Article

        4 - Finite Element Method Application in Analyzing Magnetic Fields of High Current Bus Duct
        The goal of paper is to present the magnetic field calculations in high current bus ducts. Finiteelement method is used to do this. Bus ducts under study have figure such as circle area. Thecalculations will be using mathematical relations, meshed geometric shape and an More
        The goal of paper is to present the magnetic field calculations in high current bus ducts. Finiteelement method is used to do this. Bus ducts under study have figure such as circle area. Thecalculations will be using mathematical relations, meshed geometric shape and analyzing them.Geometric mean will help us to determine the value of magnetic field. COMSOL software is appliedfor simulation studies. Calculations have been analyzed in three phase state and also, simulations areimplemented into the three dimensional position. Demonstration procedure and numericalcalculations are used for presentation the front of view of bus duct. Skin effect and connectionconfiguration between bus ducts are considered in the calculations. Aforementioned method can beused in the magnetic fields analyzing in transmission lines and electrical energy link which consist ofinsulator, easily. Typical bus duct which is applied in simulation studies produced by a pars generatorcorporation, it has been installed in Ardebil substation. Manuscript profile
      • Open Access Article

        5 - Minimizing Loss of Information at Competitive PLIP Algorithms for Image Segmentation with Noisy Back Ground
        In this paper, two training systems for selecting PLIP parameters have been demonstrated. The first compares the MSE of a high precision result to that of a lower precision approximation in order to minimize loss of information. The second uses EMEE scores to maximize v More
        In this paper, two training systems for selecting PLIP parameters have been demonstrated. The first compares the MSE of a high precision result to that of a lower precision approximation in order to minimize loss of information. The second uses EMEE scores to maximize visual appeal and further reduce information loss. It was shown that, in the general case of basic addition, subtraction, or multiplication of any two images, γ, k, and λ = 1026 and β = 2 are effective parameter values. It was also found that, for more specialized cases, it can be effective to use the training systems outlined here for a more application-specific PLIP. Further, the case where different parameter values are used was shown, demonstrating the potential practical application of data hiding. Manuscript profile
      • Open Access Article

        6 - Vehicle Logo Recognition Using Image Matching and Textural Features
        In recent years, automatic recognition of vehicle logos has become one of the important issues in modern cities. This is due to the unlimited increase of cars and transportation systems that make it impossible to be fully managed and monitored by human. In this research More
        In recent years, automatic recognition of vehicle logos has become one of the important issues in modern cities. This is due to the unlimited increase of cars and transportation systems that make it impossible to be fully managed and monitored by human. In this research, an automatic real-time logo recognition system for moving cars is introduced based on histogram manipulation. In the proposed system, after locating the area that contains the logo, image matching technique and textural features are utilized separately for vehicle logo recognition. Experimental results show that these two methods are able to recognize four types of logo (Peugeot, Renault, Samand and Mazda) with an acceptable performance, 96% and 90% on average for image matching and textural features extraction methods, respectively. Manuscript profile
      • Open Access Article

        7 - Optimal Design of UPFC Output Feed Back Controller for Power System Stability Enhancement by Hybrid PSO and GSA
        In this paper, the optimal design of supplementary controller parameters of a unified powerflow controller(UPFC) for damping low-frequency oscillations in a weakly connected systemis investigated. The individual design of the UPFC controller, using hybrid particle swarm More
        In this paper, the optimal design of supplementary controller parameters of a unified powerflow controller(UPFC) for damping low-frequency oscillations in a weakly connected systemis investigated. The individual design of the UPFC controller, using hybrid particle swarmoptimization and gravitational search algorithm (PSOGSA)technique under 3 loadingoperating conditions, is discussed. The effectiveness of proposed controller on enhancingdynamic stability is tested through eigenvalue analysis and time domain simulation. Alsononlinear and electrical simulation results show the validity and effectiveness of theproposed control schemes over a wide range of loading conditions. It is also observed that theproposed UPFC-based damping stabilizers greatly enhance the power system transientstability. Also, simulation results of coordinated design of stabilizer based on δE and mB ispresented and discussed,the system performance analysis under different operating conditionsshow that the δE-based controller is superior to the mB-based controller. Manuscript profile
      • Open Access Article

        8 - Multi Objective Optimization Placement of DG Problem for Different Load Levels on Distribution Systems with Purpose Reduction Loss, Cost and Improving Voltage Profile Based on DAPSO Algorithm
        Along with economic growth of countries which leads to their increased energy requirements,the problem of power quality and reliability of the networks have been more considered andin recent decades, we witnessed a noticeable growing trend of distributed generation sour More
        Along with economic growth of countries which leads to their increased energy requirements,the problem of power quality and reliability of the networks have been more considered andin recent decades, we witnessed a noticeable growing trend of distributed generation sources(DG) in distribution networks. Occurrence of DG in distribution systems, in addition tochanging the utilization of these systems, has provided the opportunity for these companies tobe able to design systems with lower costs. In this paper, the problem of placement andcapacity determination of DG were carried out using multiple methods. The main objectivesof issue were improving the voltage profile, losses reduction and reduce the cost of operationthat were carried out based on an economic function. Using the multiple methods to improvesome purposes and utilization of weighting coefficients provided an appropriate plan.DAPSO algorithm was used for optimization and various experiments carried out on realnetwork. Manuscript profile