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Volume 3 (3); Dec 2014
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PII: S232251141400014-3 Medical Image Enhancement by Image Fusion in Wavelet Domain |
Original Research, C14 Hojjati S. H., Hosseinzadeh M., Reihanian A. J. World. Elect. Eng. Tech., 3(3): 99-103, 2014. ABSTRACT: Owing to advances in medicine, with the increased demands on clinical services, quality enhancement of medical images attracts many attentions. The noise and contrast are the important issues related to the medical images. This paper proposes a new algorithm for noise reduction and contrast improvement of medical images which is based on wavelet transform. Firstly the image's details are obtained by Haar transform. Then, the noise of the image is removed by stationary wavelet transform (SWT). After that, different methods of image fusion are employed to enhance the mentioned image. Finally, the image histogram is equalized by contrast limited adaptive histogram equalization (CLAHE). The simulation result indicates that the proposed algorithm significantly improves the quality of an image while removing its noise. |
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PII: S232251141400015-3 Modeling and Design of Controllers for Switched Reluctance Motor Based on Asymmetrical Γ-Source Inverters |
Original Research, C15 ABSTRACT: In this paper a power electronic converter on the basis of asymmetrical Γ-Source inverter has identified to control the speed of switched reluctance motor. In this structure, the converter on the AC side is connected to the three phase power system through three phase three leg inverter while on its DC side supplies a switch reluctance motor throughan impedance network. To have the best control performance (speed control and minimum distortion effects) three loop control system includes impedance network capacitor voltage controller, motor voltage and motor speed controller have been used. Capacitor voltage controller itself contains two sub system include inner current controller in AC side and outer voltage controller to control capacitor voltage. Also speed control unit contains two parts of motor phase current control and external speed controller. Hence totally five control loop have been used to design control system. In order two design aforementioned control systems, dynamic model of asymmetrical Γ-Source inverter has been used for power electronic converters and the time domain dynamic response of motor has been used to design speed controller. The performance of proposed control system has been tested in MATLAB/simulink to prove the performance of the designed control system. |
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PII: S232251141400016-3 Path-finding in Multi-Agent, unexplored And Dynamic Military Environment Using Genetic Algorithm
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Original Research, C16 ABSTRACT: Path-finding in multi-agent, unexplored and dynamic military environment is one of the most important issues for solving in simulators. In this article a substructure of agent Path-finding is created which these agents are placed in an unexplored environment, also they communicate each other and use proposed methods to find targets to reach them. The most important aim of this article is to consider the targets behavior to decrease the required cost for reaching to the targets by improving agent’s behavior in a dynamic military environment and improving agent’s interactions. In the proposed method each agent have movement ability in a dynamic environment autonomously and they have ability to finding targets between obstacles. Therefore to solve this problem all of the necessary constraints to find path in a dynamic and unexplored environment are considered and Genetic algorithm is used. |
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PII: S232251141400017-3 Placement of Dispersed Generation with the Purpose of Losses Reduction and Voltage Profile Improvement in Distribution Networks Using Particle Swarm Optimization Algorithm |
Original Research, C17 ABSTRACT:Optimal placement of dispersed generation in electrical distribution systems was carried out considering the voltage profile improvement indexes and decreased losses in this study. It is necessary to find an inappropriate location for dispersed generation, otherwise it may result in increased costs and adverse effects on network losses and the reliability. A model to determine the optimal location and size for dispersed generation using Particle Swarm Optimization algorithm is presented in this study. For this purpose, indexes mentioned above were used in the objective function. The proposed method was applied on the IEEE 33-bus and 69-bus system and the results of dispersed generation placement in the distribution network was examined in three design positions and a position with no dispersed generation. The results indicated the competency of the proposed algorithm. |
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PII: S232251141400018-3 A Compact Monopole Antenna for Wireless Applications |
Original Research, C18 ABSTRACT: A tiny wideband microstrip-fed monopole antenna which includes of a radiating patch with two L-shaped notches and stubs at the lower corners and truncated ground plane, is suggested for various mobile communication services such as WiBro, WLAN, DMB, and UWB applications. This antenna which is presented here is designed to function over 2.3 to 10.7 GHz for S11<-10dB. In this paper, numerical analysis using Ansoft HFSS and details of the proposed antenna design approach and measured results are also presented and discussed. |
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PII: S232251141400019-3 Modeling and Optimizing the Hardness of the Melted Zone in Submerged Arc Welding Process using Taguchi Method |
Original Research, C19 ABSTRACT:Welding, as one of the most useful method for permanent joint of components, is of great importance in industry. Among the wide variety of welding processes, submerged arc welding, given its particular characteristics, is commonly used in industries. The distinguishing advantages of this method are high penetration and sedimentation rate as well as alloy development during welding by creating a cover of desired combinations of elements on the surface of work piece, which improve mechanical, corrosive, fricative and other properties. In this process, the proper selection of input parameters is necessary for high productivity and cost-effectiveness. One of the important characteristic of weld quality, which is influenced by welding parameters, is the hardness of the melted zone (HMZ). In this paper, experiments were conducted by Taguchi experimental design and Minitab 14 statistical software, and the interaction of input parameters was not taken into account. Current intensity, arc voltage, welding speed, nozzle distance from the work piece and thickness of magnesium oxide nanoparticles were considered as the input parameter and the HMZ was assumed as the response. After collecting data, the signal to noise ratio (S/N) was calculated to obtain optimal levels for all input parameters. Then, using analysis of variance (ANOVA), the significance level of (P) for each input parameter was determined and validated for the hardness of the melted area. The results show that current intensity, welding speed, arc voltage, nozzle distance from work piece and thickness of magnesium oxide nanoparticles had respectively the highest impact on the hardness of melted zone. Keywords: Submerged Arc Welding, Hardness of Melted Zone, Taguchi Method, Analysis of Variance, Optimization |
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PII: S232251141400020-3 Discretization of Cuckoo Optimization Algorithm for Solving Quadratic Assignment Problems |
Original Research, C20 ABSTRACT:Quadratic Assignment Problem (QAP) is one the combinatorial optimization problems about which research has been done in many companies for allocating some facilities to some locations. The issue of particular importance in this process is the costs of this allocation and the attempt in this problem is to minimize this group of costs. Since the QAP’s are from NP-hard problem, they cannot be solved by exact solution methods. Cuckoo Optimization Algorithm is a Meta-heuristic method which has higher capability to find the global optimal points. It is an algorithm which is basically raised to search a continuous space. The Quadratic Assignment Problem is the issue which can be solved in the discrete space, thus the standard arithmetic operators of Cuckoo Optimization Algorithm need to be redefined on the discrete space in order to apply the Cuckoo Optimization Algorithm on the discrete searching space. This paper represents the way of discretizing the Cuckoo optimization algorithm for solving the quadratic assignment problem. Keywords: Quadratic Assignment Problem (QAP), Meta-Heuristic Algorithms, Discrete Cuckoo Optimization Algorithm (DCOA). |
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