International Journal of Engineering
Volume:27 Issue: 1, Jan 2014

In this paper, a new algorithm which is the result of the combination of cellular learning automata and frog leap algorithm (SFLA) is proposed for optimization in continuous, static environments.At the proposed algorithm, each memeplex of frogs is placed in a cell of cellular learning automata. Learning automata in each cell acts as the brain of memeplex, and will determine the strategy of motion and search.The proposed algorithm along with the standard SFLA and two global and local versions of particle swarm optimization algorithm have been tested in 30-dimensional space on five standard merit functions. Experimental results show that the proposed algorithm has a very good performance.

Keyword Spotting is a well-known method in document image retrieval. In this method, Search in document images is based on query word image. In this Paper, an approach for document image retrieval based on keyword spotting has been proposed. In proposed method, a framework using relevance feedback is presented. Relevance feedback, an interactive and efficient method is used in this paper to improve performance of document image retrieval System (DIRS). In the proposed method we compare several strategies of positive and negative feedback which include “Only Positive Feedback”, “Only Negative Feedback” and “Positive and Negative Feedback”. Experiments show that using relevance Feedback in DIR achieves better performance than common DIR.

The main issue in any image zooming techniques is to preserve the structure of the zoomed image. The zoomed image may suffer from the discontinuities in the soft regions and edges; it may contain artifacts, such as image blurring and blocky, and staircase effects. This paper presents a novel image zooming technique using Partial Differential Equations (PDEs). It combines a non-linear Fourth-order PDE method with the Locally Adaptive Zooming (LAZ) algorithm. The proposed method uses high-resolution image obtained from LAZ algorithm to construct zoomed image by Fourth-order PDE. This proposed method preserves edges and minimizes blurring and staircase effects in the zoomed image. In order to evaluate image quality obtained from the proposed method, this paper focuses on both subjective and objective assessments. The results of these measures on a variety of images show that the proposed method is superior over the other image zooming methods.

This research puts forward rough finite state automata which have been represented by two variants of BDD called ROBDD and ZBDD. The proposed structures have been used in networked system diagnosis and can overcome cominatorial explosion. In implementation the CUDD - Colorado University Decision Diagrams package is used. A mathematical proof for claimed complexity are provided which shows ZBDD representing has superiority in space and time complexity to ROBDD representing.

A wireless ad hoc network typically refers to any set of wireless networks where all devices have equal status on a network and are free to associate with any other wireless ad hoc network devices in their range. As the nature of these networks, they commonly do not have external power supplies, and each node has a limited internal power source. In this paper, we put forward a new routing protocol that is light enough for energy constrained networks, and find routs on the basis of remaining power of each node. Besides, we have also taken some other factors into the consideration. These factors include the ratio of remaining power of a node to the distance of the node from next receiving node. And also the ratio of remaining power of current node to the average remaining power of whole network. This protocol puts emphasis on routing in such a way that the network stays heterogeneous in terms of remaining power of nodes. This heterogeneity brings on a longer network lifetime

Routing is an important challenge in WSN due to the presence of hundreds or thousands of sensor nodes. Low Energy Adaptive Clustering Hierarchy (LEACH) is a hierarchical routing and data dissemination protocol. LEACH divides a network domain into several sub-domains that are called clusters. Non-uniformity of cluster distribution and CHs selection without considering the positions of other sensors may reduce the quality of cluster selection. Sensor nodes send data packets over long distances. Imperialist Competitive Algorithm (ICA) is an optimization algorithm inspired by social phenomenon. It considers colonization process as a stage of socio-political evolution. We improve performance of the LEACH algorithm using imperialist approach and study efficacy of it in terms of energy consumption, coverage and cluster uniformity and compare with those of the LEACH algorithm. Selection of suitable value for radio communication radius over the network lifetime is a trade-off between connectivity and sensors energy consumption. Empowering LEACH with ICA helps to find the best location of a CH in every cluster, it can conserve energy significantly, increase network lifetime, and maintain network connectivity. It can significantly reduce the number of active sensors going out of range over the lifetime of a network.

Alzheimer\''s disease is characterized by impaired glucose metabolism and demonstration of amyloid plaques. Individual positron emission tomography tracers may reveal specific signs of pathology that is not readily apparent on inspection of another one. Combination of multitracer positron emission tomography imaging yields promising results. In this paper, 57 Alzheimer\''s disease neuroimaging initiative subjects that had FDG and PiB-positron emission tomography neuroimaging scans at the same time were used for development of proposed multitracer classification method. The subject’s brain image was automatically parcellated into 48 pre-defined regions of interest. Then 96 features are extracted for each subject. The principal features are extracted using principal component analysis, then they are combined based on intersection strategy. Finally, a support vector machine is adopted to evaluate the classification accuracy. Combination of two tracers with positron emission tomography scan yielded a higher diagnostic accuracy in Alzheimer\''s disease compared to individual tracer and other combination methods.

This paper presents an energy management strategy to supply residential load by hybrid fuel cell power plant (FCPP). Economical fuel cell (FC) model includes thermal load, local electrical load, operational cost, startup cost and different tariffs on electricity during the day hour is discussed. Several Strategies have been presented for supplying residential load (electrical and thermal loads) based on thermal energy recovering and saving. The extended Genetic algorithm (GA) is used to determine optimal operation of FCPP with respect to six-minute time steps in load pattern change. To demonstration proposed algorithm, three different strategies for optimal supplying both electrical and thermal loads are presented with respect to thermal energy recovering and saving.

In this paper we present a new model for calculating the capacitance of MEMS sensor with corrugated diaphragm. In this work the effect of residual stress is considered on deflection of diaphragm and capacitance of sensor. First, a new analytical analyzes have been carried out to derive mathematic expressions for central deflection of corrugated diaphragm and its relationship with residual stress. Then the capacitance and sensitivity of sensor using corrugated diaphragm with residual stress are calculated under various parameters such as bias voltage and pressure. The analytical results are compared with simulation using Finite Element Method (FEM). The results show that the new analytical model is very close with simulation results.

Winding function method (WFM) provides a detailed and rather simple analytical modeling and simulation technique for analyzing performance of faulty squirrel-cage induction motors (SCIMs). Such analysis is mainly applicable for designing on-line fault diagnosis techniques. In this paper, WFM is extended to include variable degree of magnetic saturation by applying an appropriate air gap function and novel techniques for estimating required saturation factor and angular position of the air gap flux density. The resultant saturable winding function method (SWFM) is properly applied for analyzing SCIMs with broken rotor bars and for identifying the saturation effect on the related fault indexes. Comparing simulation results to the corresponding experimental results show higher accuracy of the SWFM. This means that more precise fault diagnosis techniques can be designed by using the proposed saturable modeling technique.

Recent developments in robotics automation have motivated researchers to improve the efficiency of interactive systems by making a natural man-machine interaction. Since speech is the most popular method of communication, recognizing human emotions from speech signal becomes a challenging research topic known as Speech Emotion Recognition (SER). In this study, we propose a Persian emotional speech corpus collected from emotional sentences of drama radio programs. Moreover, we proposed a new automatic speech emotion recognition system which is used both spectral and prosodic feature simultaneously. We compared the proposed database with the public and widely used Berlin database. The proposed SER system is developed for females and males separately. Then, irrelevant features are removed using Fisher Discriminant Ratio (FDR) filtering feature selection technique. The selected features are further reduced in dimensions using Linear Discriminant Analysis (LDA) embedding feature reduction scheme. Finally, the samples are classified by a LDA classifier. The overall recognition rate of 55.74% and 47.28% is achieved on proposed database for females and males, respectively. Also, the average recognition rate of 78.64% and 73.40% are obtained for Berlin database for females and males, respectively.

In this paper a new method is introduced for root detection in minirhizotron images for root investigation. In this method firstly a hypothesis testing framework is defined to separate roots from background and noise. Then the correct roots are extracted by using an entropy-based geometric level set decision function. Performance of the proposed method is evaluated on real captured images in two different scenarios. In the first scenario images contain several roots however the second scenario belongs to no-root images, which increases the chance of false detection error. The obtained results show the greater ability of the proposed method in root detection compared with present approaches in all examined images. Furthermore it can be shown that better detection of roots in proposed algorithm not only doesn''t lead to extracting more false particles but also it decreases rate of false detections compared to existing algorithms.

A permanent physical fault in communication lines usually leads to a failure. The feasibility of evolution of a self organized communication is studied in this paper to defeat this problem. In this case a communication protocol may emerge between blocks and also can adapt itself to environmental changes like physical faults and defects. In spite of faults, blocks may continue to function since a self organized nature can provide self-healing capabilities. In the present paper, Evolvable Hardware is to create such a fault tolerant communication without any predefined protocol using a GA algorithm. Evolvable Hardware is a concept that aims the application of evolutionary algorithms to hardware design. The feasibility of this idea is studied in simulation of two reconfigurable blocks that are intended to transmit video streams through their communication lines. Permanent physical faults are induced in the communication lines between Evolvable Hardware blocks. Though the results show the emergence of fault tolerant protocols among Evolvable Hardware blocks without human intervention, there are some limitations in functional and gate level evolution of the blocks. Thus, a new adaptive approach is presented in this paper to defeat some limitations like the stalling effect of GA in faulty conditions.

A discrete event system (DES) is a dynamic system that evolves in accordance with the abrupt occurrence, at possibly unknown irregular intervals, of physical events. Because of the special nature of these systems, different tools are currently used for their analysis, design and modeling. The main focus of this paper is the presentation of a new modeling approach of Discrete Event Systems. The proposed approach is based on hybrid model which combines Interval Constrained Petri Nets (ICPN) and Timed Automata. These tools allow us to evaluate, respectively, the quality variations and to manage the flow type disturbance. An example analysis illustrates our approach.

In this paper, a boost converter with a clamp circuit is proposed for high intensity discharge (HID) lamp application. The clamp circuit provides zero voltage turn on for both main and clamp switches. Compared to conventional boost converters, the proposed converter has the following advantages: (i) high voltage gain without suffering from extreme duty ratio, (ii) low stress on the switches and (iii) low switching losses. Simulation and experimental results show that the voltage stress on the switches are well within acceptable limits and prove the converter’s performance over a wide load range.

In this paper, the immune controller, is used to control the paralleled DC-DC converters. A PID controller is first applied and its coefficient is optimized using an intelligent (PSO) algorithm. Immune controller is then added to PID controller and an immune PID controller is formed. Two methods have been suggested to determine non-linear behavior of immune controller. In the first method, an exponential function is suggested and its unknown coefficient is optimized using PSO algorithm. In the second method, fuzzy logic has been used. Performance of the proposed control methods in the presence of various disturbances is investigated over a sample paralleled DC-DC converter and the effectiveness of the applied immune controller is verified with the comparison of simulation results. The results show the improvement of system performance with Immune PID controller by the two suppression function in comparison with the PID controller.

In the presented paper, a sensorless driver circuit is designed, constructed and tested to control two types of three-phase Switched Reluctance Motor (SRM). The presented control algorithm has three steps. In the first step, the SRM is controlled by an open-loop method. In the second step, mathematical model of the SRM phase, motor parameters and flux-current-rotor position relation are used in order to calculate the position of the rotor and then control the motor in low speed. In the third step, the current waveform of the excited phase of the motor is utilized in order to detect the rotor position and control the SRM in high speed. In the presented circuit, an Atmega128 AVR microcontroller is used to implement the control algorithms and generate gate pulses of transistors. Asymmetric bridge converter with N-channel Mosfets is used in order to excite the winding of phases. The parameters of the SRMs which are required for designing the sensorless driver circuit are obtained by simulating and analyzing the motors by Finite Element Method (FEM). The constructed circuit is tested in laboratory by driving the selected SRMs in no-load condition and the operational results are obtained and compared to each other at the end.

The gimbal stabilization mechanism is used to provide the stability to an object mounted on the gimbal by isolating it from the base angular motion and vibration. The purpose of this paper is to present a model of control servo system for one axis gimbal mechanism using a cascade PID controller. The gimbal torque relationships are derived by taking into consideration the base angular motion. The conventional PID controller and three cascade controller structures are investigated. The servo control loop is built and modelled in MATLAB/Simulink using these controllers. The simulation results are compared and the servo system performance is analysed for each controller in terms of performance criteria. The comparison results prove that a further improved system performance is achieved using I-PD controller as compared to the system performance obtained when the other controllers are utilized. The paper’s value lies in designing the servo control system using a modified controller constitutes of tow parallel I-PD controllers related with a switch depends on the base angular rate as a threshold. The results show that the modified system realizes the desired servo system requirements.