Journal of Intelligent Procedures in Electrical Technology (JIPET)

Published by Islamic Azad University, Najafabad Branch
Online ISSN: 2322-3871
Publications
Article
This paper aims at applying H.264/AVC in medical video compression applications and improving its compression performance with higher perceptual quality and lower coding complexity. We propose a new method that uses lossless compression in the region of interest (ROI) and very high rate lossy compression in other regions. The propose method achieves a fast intra- and interprediction mode decision that is based on encountering coarse MBs for intra- and inter- prediction mode decision of the background region and fine MBs for the ROI region. The MBs of the background region are encoded with the maximum quantization parameter allowed by H.264/AVC in order to maximize the number of null coefficients. Also, in order to further reduce the computational complexity, a two-adaptive search range decision method (proposed previously by the authors) is enhanced using the ROI concept. Experimental results show that the proposed algorithm achieves a higher compression rate on medical videos with a higher quality of ROI with low coding complexity when compared to other standard algorithms reported in the literature and our previous algorithm.
 
Article
The all-optical transparent wavelength routed network is a promising candidate for the next-generation backbone network to provide large bandwidth at low cost. Due to transmission impairments, present in fibers and optical components, may significantly affect the quality of a lightpath, and, hence, in wavelength routed transparent optical networks, the best routing optimization, which is determined only by network-layer performance, might not be the best one or even worse after physical-layer performance taken into account. In order to overcome the above limitation, in this paper, we propose that routing optimizations should be evaluated from both network-layer performance and physical-layer performance and the best routing optimization should be chosen based on the overall performances, not just the network-layer performance.
 
Article
The Application of parabolic shaped ridge waveguide is presented for excitation of a centreline longitudinal shunt slot antenna. The proposed method is realized by adding parabolic shaped to the ridge of the single ridge waveguide. The parabolic shaped ridge is placed exactly under the longitudinal slot and the slot is placed along centreline of the waveguide. It is shown that for a typical slot, the slot normalized conductance can be increased by increasing the parabolic shaped depth. The simulation results show that the proposed structure can be considered as a proper candidate for replacing the conventional longitudinal shunt slot.
 
IPM motor drive system block diagram
Torque response The d-q axis currents are also shown in Fig. (5). The simulation results confirm desirable motor performance under the proposed efficiency optimization controller.
d-q axis current response
Error signal of e 1
Article
In this paper, a nonlinear loss minimization control strategy for an interior permanent magnet synchronous motor (IPMSM) based on a newly developed sliding mode approach is presented. This control method sets force the speed control of the IPMSM drives and simultaneously ensures the minimization of the losses besides the uncertainties exist in the system such as parameter variations which have undesirable effects on the controller performance except at near nominal conditions. Simulation results are presented to show the effectiveness of the proposed controller.
 
Article
In phased array systems, increasing the array length and consequently increasing the number of antenna elements are needed to improve spatial resolution. It can be addressed by MIMO radars using orthogonal signals from multiple transmitters and using the virtual array. Virtual element's locations are derived from the convolution of the physical elements of the transmitter and receiver. To understand the functionality of MIMO radars, virtual array has been introduced. As the virtual array be larger, the radar angle resolution increase. Increasing the degree of freedom of the virtual array is highly dependent on the array of transmitter and receiver elements placement. The Nested Array which is one of the well-known methods in alignment of MIMO radar array elements, is investigated. In this article, the new nested array is examined and implemented in one dimension. The very innovative idea of this article is to use the new 2D nested array. A multi-step approach for implementing two-dimensional arrays using a new nested array for a MIMO radar is presented which can be generalized to any other structure with different number of elements. Finally, the advantages of the proposed method in terms of angular bandwidth of the main radar are presented. The results show that the proposed method is much more efficient than the other methods. The comparative results presented at the end of this article shows that the half-power beam width of the proposed method is approximately 0.3 degrees while this value for the nested method is more than 2 degrees.
 
Equivlaent circuit of induction motor 
Flowchart of the proposed algorithm 
Convergence characteristics of various algorithms for objective function of Eq. (12) 
Article
Today, most energy consumption in industry is related to induction motors. Evaluation of induction motor’s efficiency is an important issue for life estimation, extending the life and energy saving managements. Using the estimated efficiency of the induction motor, its performance can be judged and replacing the existing low efficiency motor by a high efficiency motor could be decided. In this paper, a novel and efficient method based on Modified Artificial Bee Colony (MABC) algorithm is presented for efficiency estimation in the induction motors. The main advantage of the proposed method is efficiency evaluation of induction motor without any intrusive test. In order to demonstrate the capabilities of the proposed method, a comparison with other intelligent optimization algorithms is performed. Then, one of the important applications of efficiency estimation, which replaces the high efficiency induction motors instead of conventional motors, is discussed. The results of the calculation of energy savings show that if a standard motor is replaced with a high efficiency motor, energy savings will be significant.
 
PDP of XOR circuits in terms of load capacitor variation (VDD=0.65 V, Cload=2.1 fF and frequency=100 MHz)
PDP of XOR circuits in terms of operating frequency variation (VDD=0.65 V, Cload=2.1 fF and frequency=100 MHz)
PDP of XOR circuits in terms of temperature variation (VDD=0.65 V, Cload=2.1 fF and frequency=100 MHz)
Article
The XOR gate is one of the basic building blocks in the Full Adder (FA) circuit, whose performance improvements can lead to improved Full Adder. For this purpose, in this paper, a new low voltage XOR cell based on Carbon Nanotube Field Effect Transistor (CNTFET) is proposed. The main design goals for this new circuit are low power dissipation, low leakage current and full voltage swing at a low supply voltage (Vdd = 0.5 V). Several XOR circuits were completely simulated using HSPICE with 32nm CMOS and 32nm CNTFET technologies at a low supply voltage. The proposed XOR circuit is compared with the previously known circuits and its outstanding performance is shown. Simulations show that the new low voltage XOR has lower power dissipation, less leakage current and lower PDP than other XOR circuits, and is resistant to process variations. Based on the results obtained at Vdd=0.5 V ,frequency=250 MHz and Cload=3.5 fF, the proposed XOR shows propagation delay of 149.05 ps, power consumption of 716.72 pW, leakage power of 25.1 pW and PDP of 10.683x10-21 J. The proposed XOR can be used well in low voltage and low power Full Adder circuits.
 
Article
One of the most prominent challenges in meeting the demand is the scarcity of radio resources. Cognitive radio is one of the techniques has been proposed for efficiently utilizing the radio resources. In Cognitive Radio CR) networks, the CR users have opportunities to access the licensed spectrum bands assigned to the primary users (PUs). Since the PUs have priorities to use the bands, the CR users are not allowed to generate unacceptable interference to them. In this paper, we investigate power allocation schemes for CR networks with two users where one users uses direct transmission and the other uses AF relay-aided transmissions. We first formulate an overall rate optimization problem with interference constraints to the PU and peak power constraints at each node and obtain solutions by theoretical analysis. We also simulate the solution base on different location of the relay and different location of the PU network.we compare the results with equal power allocation
 
Article
In this paper, an ultra-low-power, second-order, discrete-time sigma-delta converter is proposed for hearing aids application. In portable biomedical devices such as hearing aids that permanently use, the battery lifetime and power dissipation are very considerable. In a typical delta-sigma modulator, the operational trans-conductance amplifiers (OTAs) are the most power-consuming parts. The OTAs elimination in the converters is now challenging. Therefore, the converter with a self-biased fully differential inverter-based amplifier was designed with only 1.15 µw static power dissipation at a 1-volt power supply. The inverter-based amplifier was used instead of the OTAs in two stages of the modulator. The modulator’s structure is CIFB, single-loop, and single bit. The proposed differential modulator was designed and simulated using a standard 180 nm CMOS technology, which obtained spurious free dynamic range (SFDR) and signal to noise and distortion ratio (SNDR) of 95.2878 dB and 64.004 dB, respectively. The sampling frequency is considered 2.56 MHz, and the input signal bandwidth is 10kHz. The modulator consumes power just about 5.1091 µW, and the Walden figure of merit (FOMW) achieves 0.197 pj/step.
 
Moren's proposed network for emotional learning [30] Algorithm 1: Brain Emotional Learning (BEL) 1. Input: Matrix sc*n including c patterns with n features, MaxIt (the number of iteration). 2. Output: Adjusted v-weights, w-weights. 3. Begin 4. Initialize v-weights, w-weights randomly. 5. Initialize α, ß. 6. While t<MaxIt 7. Begin 8. Initialize EA, EO. 9. For i=1:C 10. Begin 11. Take ith pattern. 12. Ath=maxj (si (j)). 13. For j=1: n 14. Begin 15. Ai(j) = si (j)* vi (j). 16. Ai(n+1) = Ath*Vi (n+1). 17. EA=EA + Ai(j). 18. Oi(j) = Si(j) * wi(j). 19. EO = EO + Oi (j). 20. E = EA-EO. 21. calculate R by Eq. (6). 22. ∆vi= α*(si (j)* max (0, R -EA)). 23. ∆wi=β*(si (j)* (E-R)). 24. update vi (j). 25. update wi (j). 26. end for 27. end for 28. end while 29. Return v-weights, w-weights. 30. end ( ‫شکل‬ 5 :) ‫کد‬ ‫شبه‬ ‫مغز‬ ‫عاطفی‬ ‫یادگیری‬
Article
Alzheimer's disease is one of the most common diseases in the 21st century. Alzheimer's patients lose their brain cells gradually and eventually die. It is often diagnosed when the symptoms appear and little work can be done for the patient. Using of learning algorithms is useful for diagnosing of Alzheimer. Previous studies used Support Vector Machine, K-Nearest Neighbor, and Linear Discriminant Analysis in order to diagnose the disease. These methods have some problems such as low accuracy, high computation complexity or high execute time. Therefore, in this research, a method based on brain emotional learning and wavelet feature is used. First, the white and gray matters of the brain were separated by a threshold selection method. Second, the texture properties of the images were extracted by wavelet transform algorithm. Third, the dimensional reduction is done on the properties extracted by principal component analysis. Finally, the features were classified using Brain Emotional Learning Algorithm and Brain Emotional Learning Based Pattern Recognizer. Results showed that run time of brain emotional learning algorithm is 0.22 second and Brain Emotional Learning algorithm with 95% accuracy and Brain Emotional Learning Based Pattern Recognizer with 97% accuracy are better than Support Vector Machine with 83% accuracy.
 
Article
Age-Related Macular Degeneration (AMD) is the second disease diabetes which causes blindness in aged people. The only remedy for AMD is intravenous injection of Bavecizumab. To prove the efficiency of remedy, the degenerated cells in Macula should be measured. In this paper, the new software is introduced to measure Auto-Fluorescence in Macula part of retina in order to determine the number of degenerated cells. This system is consists ofthree main parts: low level pre-processing, image analysis and images understanding. Experiments have been done on a database of 34 retina images of before and after AMD patients remedy. The average number of decreased degenerated cells after remedy was 15134. In clinical reviews, the founded relation to disinflation of Macula has been proved, while there were no proved relations to the vision decreasing or increasing ofpatients.
 
FN values for different K.
Total accuracy for different K in seizure detection by KNN algorithm.
Voronoi-Tessellation diagram for 30 sample of EEG signals  
Article
Seizure detection using brain signal (EEG) analysis is the important clinical methods in drug therapy and the decisions before brain surgery. In this paper, after signal conditioning using suitable filtering, the Gamma frequency band has been extracted and the other brain rhythms, ambient noises and the other bio-signal are canceled. Then, the wavelet transform of brain signal and the map of wavelet transform in multi levels are computed. By dividing the color map to different epochs, the histogram of each sub-image is obtained and the statistics of it based on statistical momentums and Negentropy values are calculated. Statistical feature vector using Principle Component Analysis (PCA) is reduced to one dimension. By EMD algorithm and sifting procedure for analyzing the data by Intrinsic Mode Function (IMF) and computing the residues of brain signal using spectrum of Hilbert transform and Hilbert – Huang spectrum forming, one spatial feature based on the Euclidian distance for signal classification is obtained. By K-Nearest Neighbor (KNN) classifier and by considering the optimal neighbor parameter, EEG signals are classified in two classes, seizure and non-seizure signal, with the rate of accuracy 76.54% and with variance of error 0.3685 in the different tests.
 
Article
Design and Simulation of a Compact UWB MIMO Antenna with Mutual Coupling Reduction Narges Malekpour (1) - Mohammad Amin Honarvar (2) - Abdolmehdi Dadgarpour(3) (1) MSc - Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran. n.malekpour20012@gmail.com (2) Assistant Professor - Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran. Amin.Honarvar@pel.iaun.ac.ir (3) PhD Student, Institute de la Recherche Scientific, Energie, Materiaux et Telecommunications (INRSEMT) , Montreal, Canda In this paper, A compact multiple-input-multiple-output (MIMO) antenna with a small size of 26×31mm2 is proposed for portable ultrawideband (UWB) applications. The antenna consists of two square-monopole antenna with microstrip-fed by a 50- Ω printed on one side of the substrate. To enhance isolation and increase impedance bandwidth, two long ground stubs are added to the ground plane on the other side. Simulation is used to study the antenna performance in terms of reflection coefficients at the two input ports, coupling between the two input ports, radiation pattern, realized peak gain, efficiency and envelope correlation coefficient. Results show that the MIMO antenna has an impedance bandwidth ( for S22< -10 dB) of larger than 3.1–10.6 GHz, low mutual coupling ( for S21< 3 dB) of less than -16 dB, and a low envelope correlation coefficient of less than 0.003 across the frequency band, making it a good candidate for portable UWB applications. Index Terms: Multiple-input-multiple-output (MIMO) antenna, ultrawideband (UWB), mutual coupling reduction
 
Fault Tree of a mentioned example 
Fuzzy triangular membership function as a basic event in Fault Tree 
Article
A fault tree illustrates the ways through which a system fails. It states different ways in which combination of faulty components result in an undesired event in the system. Being used in phases such as designing and exploiting industrial systems, and the designers able to evaluate the dependability attributes such as reliability, MTTF and sensitivity. In addition, in the mentioned ability, the fault tree is a systematic method for finding systems bottlenecks and weakness point. In spite of its extensive use in evaluating the reliability of systems, fault tree is rarely used in calculating sensitivity. In the last decade, few researches has been conducted in this field, however these methods are not applicable to large scale systems and are not systematic. This paper provides a systematic method for evaluating system sensitivity through fault tree. Then, it introduces sensitivity of NMR architecture as one of the common structures of fault tolerance which is used for enhancing systems’ reliability, safety and availability in industry. This article presents a comprehensive and parameterized formula for NMR structure's sensitivity. The presented method can be a great help for designing and exploiting reliable systems engineers in systematic and instant calculation of sensitivity by means of fault tree.
 
Effect of cable capacitance on the starting current peak  
Sample system for the starting current study  
Relative errors of learning and testing sets for LM algorithm
Equivalent circuit of induction machine; (a) qaxis , (b) d-axis  
Article
Induction motors (IMs) are widely used in industry including it be an electrical or not. However during starting period, their starting currents are so large that can damage equipment. Therefore, this current should be estimated accurately to prevent hazards caused by it. In this paper, the artificial neural network (ANN) as an intelligent tool is used to evaluate starting current peak of IMs. Both Multilayer Perceptron (MLP) and Radial Basis Function (RBF) structures have been analyzed. Six learning algorithms, backpropagation (BP), delta-bar-delta (DBD), extended delta-bar-delta (EDBD), directed random search (DRS), quick propagation (QP), and levenberg marquardt (LM) were used to train the MLP. The simulation results using MATLAB show that most developed ANNs can estimate the starting current peak of IMs with good accuracy. However, it is proven that LM and EDBD algorithms present better performance for starting current evaluation based on average of relative and absolute errors.
 
A normal capnogram  
The overall view of the applied methods  
The correlation coefficients of some capnogram signals after filtering with different spans  
Correlation coefficients between the original capnogram signal and estimated signals using different LPC orders  
Article
In this paper, a new prognostic index to detect the severity of asthma by processing capnogram signals is presented. Previous studies have shown significant correlation between the capnogram and asthmatic patient. However, most of them used conventional time-domain methods and based on assumption that the capnogram is a stationary signal. In this study, by using linear predictive coding (LPC) coefficients and autoregressive (AR) modelling (Burg method), the capnogram signals are processed. Then, a number of six features including α1, and α4 from LPC and power spectral density (PSD) parameters through AR modelling are extracted. After that, by means of receiver operating characteristic (ROC) curve, the effectiveness of the extracted features to differentiate between asthmatic and nonasthmatic conditions is justified. Finally, selected features are used in a Gaussian radial basis function (GRBF) network. The output of this network is an integer prognostic index ranging from 1 to 10 (depends on the severity of asthma) with an average good detection rate of 90.15% and an error rate of 9.85%. In the other word, based on the results, sensitivity and specificity of this algorithm are 93.54% and 98.29%, respectively. This developed algorithm is purposed to provide a fast and low-cost diagnostic system to help healthcare professional involved in respiratory care as it would be possible to monitor severity of asthma automatically and instantaneously.
 
Article
Nowadays, service-oriented systems according to possibility of using in heterogeneous distributed environments and being independent of the specific technology, also with the existence of large-scale dynamic system with changeable requirements, are highly regarded. Cloud services are one of the implementation methods of service-oriented concepts. Increasing the tendency of users to use cloud computing, encourages service vendors to provide services with different non-functionality features. Mostly single services couldn’t satisfy users’ requirements, so it’s necessary to compose some services to achieve the demand service. With the increasing of service providers, also services in the internet service pools, selecting the optimal service from a set of functionality equivalent candidates which are differ in QoS, becomes an important NP-Hard research problem. Therefore increasing the quality of composite services is a vital challenge and since the quality of cloud composite services derived from previous approaches can still be increased, in this research, we have tried to increase the quality of cloud composite services using the Symbiotic Organism Search Algorithm. Simulations are conducted in Matlab environment and the results are compared to three famous algorithms including GA, ACO and PSO. The comparisons demonstrate the remarkable superiority of SOS in result's quality, stability and scalability, also 13% improvement.
 
Article
Renewable energy has been developed in recent years due to the limited sources of fossil fuels, their possibility of depletion, and related environmental issues. The main challenge of these types of systems is reaching the optimum size in order to have an affordable system based on storing solar and wind energy. In this paper, optimization of a solar-wind hybrid system is presented with a saving battery system for supplying a specific hourly load annually to minimize annual system expenses and the probability of loss of power supply probability (LPSP). Annual expenses of the system include initial investment, maintenance, and replacement costs. The purpose of optimization is to determine the numbers of solar panels, wind turbines, batteries, the height of the wind tower, and the angle of the solar panel toward solar radiation. For this issue, a new method named grasshopper optimization algorithm (GOA) is employed. Also, the effects of changes in inverter efficiency, load demand, and maximum probability of LPSP on system designing are evaluated. Simulation results show that the efficiency reduction, load increase, and increasing the load and maximum reliability in the system in the form of reducing of LPSP lead to an increase in annual energy costs of systems. Furthermore, the results indicate the superiority of the GOA method toward particle swarm optimization (PSO) in reaching better target function and less cost.
 
Burst-rate scheduling model
Buffer quantization by MBT
Article
Quality of Service (QoS) provisioning is very important in the next computer/communication networks because of increasing multimedia services. Hence, many investigations are performed in this area. Scheduling algorithms affect QoS provisioning. Lately, a scheduling algorithm called Regulated Burst Service Scheduling (RBSS) is suggested by the author in [1] to provide a better service to bursty and delay-sensitive services such as video. One of the most significant features in RBSS is considering the burstiness of arrival traffic in the scheduling algorithm. In this paper, an upper bound of queue length or buffer size and service curve is calculated by Network Calculus analysis for RBSS. Because in RBSS queue length is a parameter that is considered in scheduling arbitrator, analysis results from a differential inequality to obtain service curve. To simplify, arrival traffic is assumed to be linear that is defined in the paper clearly. This paper helps to analyze the delay in RBSS for different traffic with different specifications. Therefore, QoS provisioning will be evaluated.
 
The Bit Error Rate performance for three detection methods in typical urben area
The Bit Error Rate performance for three detection methods in typical bad urben
Article
To improve the quality of service, digital terrestrial television transmitters must increase channel capacity and data rates, and also stabilize the channel against fading. MIMO (multi-input multi-output) system equipped with low correlation bipolar antennas, is one of the solutions to achieve this goal. However, the use of bipolar antennas causes interference due to cross-polarization in the receiver, which reduces the transmission rate and transmission capacity. To reduce the effect of depolarization, the use of gradual interference detectors is very effective. In this paper, a new detection algorithm based on the gradual elimination of interference detection is presented. The main feature of this algorithm is a change in the step of gradual elimination of interference. To evaluate the proposed method, a multi-digital terrestrial television transmitter system bipolar inputs were simulated. In this paper, it will be shown that in the proposed detection method, the bit error rate performance In terms of SNR, it has improved compared to other detection methods based on the gradual elimination of interference detectors, such as SIC-ZF, SIC-MMSE.
 
Single-line diagram of the distributed network
Article
Capacitor placement at the substation is one of the effective methods for loss reduction and efficiency increasing of the power systems. In this paper, a novel method for capacitor placement on the secondary side of the distribution transformers is carried out. The mathematical method of Mixed–Integer Linear Programming (MILP) algorithm is used for paper goal to increase the Net Present Value (NPV), resulting from the loss reduction. Due to the variability of the loads, a special template is used for loads modelling. Not only the constant loads, but also three types of industrial, residential and commercial loads are assessed with the proposed method. Then, the results are discussed in order to re-grade loads. Also, the proposed method are compared with two methods as Particle Swarm Optimization (PSO) algorithm and Teaching–Learning Based Optimization (TLBO) algorithm. All of the tests are simulated with MATLAB software and total time of problem is considered as ten years.
 
The distribution of the Lorentz forces density at the different states: a) Before fault, b) After first phase cutting off, c) After second phase cutting off, d) After third phase cutting off
Article
In this paper, Finite Element Method (FEM) is used to study the ferroresonance phenomenon from the perspective of the electromagnetic forces introduced on the transformer windings. In order to simulate this phenomenon, a consecutive 3–phase short–circuit fault is considered to be on the primary side at a relatively distant from the transformer. Then, due to the capacitance of the line, between the error point and transformer, the single–phase short–circuit faults are generated, one–by–one. Because of the switching, for isolation feeder from the fault point, the ferroresonance appears in power system. Then, voltages and currents of the primary and secondary windings will be changed. The effect of current changes on the forces that transformer coils withstand, when the ferroresonance happens, is an interesting topic to this paper. With modeling of the transformer and feeder switching in the FLUX 12.2 software, the ferroresonance condition is simulated. Due to the dependence of the ferroresonance on the non-linearity of the magnetic characteristic of the transformer core, Jiles–Atherton vector hysteresis model is used to modeling the core hysteresis loops for enhancement the results accurate.
 
Article
Knowledge extraction from detected document image is a complex problem in the field of information technology. This problem becomes more intricate when we know, a negligible percentage of the detected document images are valuable. In this paper, a segmentation-based classification algorithm is used to analysis the document image. In this algorithm, using a two-stage segmentation approach, regions of the image are detected, and then classified to document and non-document (pure region) regions in the hierarchical classification. In this paper, a novel valuable definition is proposed to classify document image in to valuable or invaluable categories. The proposed algorithm is evaluated on a database consisting of the document and non-document image that provide from Internet. Experimental results show the efficiency of the proposed algorithm in the semantic document image classification. The proposed algorithm provides accuracy rate of 98.8% for valuable and invaluable document image classification problem.
 
Article
With the spread of applications of wireless sensor networks, in recent years, the use of this type of network in order to monitor the environment and analyze data collected from specific environments in a variety of ways has become very common. Wireless sensor networks are one of the best options for collecting data from the environment due to their easy configuration and no need for expensive equipment. The energy of sensors in wireless sensor networks is limited, which is a major challenge due to the lack of a fixed charge source. Because most of the sensors' energy is wasted during data transmission, a sensor that transmits more data than others and transmits data over long distances with packets will run out of energy sooner than others. When a sensor in the network runs out of energy, the network process may be disrupted. Therefore, due to the dynamic topology and distributed nature of wireless sensor networks, designing energy efficient routing protocols is one of the main challenges. Therefore, in this article, energy-aware routing protocol based on multi-objective particle swarm optimization algorithm is presented. In the proposed approach, the fitness function of the particle swarm optimization algorithm for selecting the optimal cluster head based on quality-of-service goals including residual energy, link quality, end-to-end delay and delivery rate. The simulation results show that the proposed approach has less energy consuming and extend network lifetime due to balancing the goals of quality-of-service criteria than other approaches.
 
Article
Cognitive Relay network is a plan to remove some problem such as the limited Coverage and limited spectrum. This strategy permit secondary users to use a frequency band( spectrum), which is dedicated to the primary users. The secondary networks employ a relay node to extend the communication range. Also the relay using to improve the outage probability of the network.For coexisting between primary and secondary network, it is necessary that the secondary network control the transmit power in their networks. Primary and secondary users have interference effect on each other. In this paper we consider both interference. In addition to the provision on the transmit power of the secondary users We consider the effect of the interference cause by primary user on secondary network
 
Article
In recent years, low-power transceivers have found wide applications in medical engineering. In this paper, the system design and simulation of a low-power implantable receiver are presented for the case of stimulating brain cells. The receiver shows a high data rate in the industrial scientific and medical (ISM) band for being used in a bidirectional wireless full-duplex link and communication between the implanted system and the outside world. The proposed receiver has a non-coherent structure and operates at a frequency of 2.4 GHz with on-off keying (OOK) modulation. This receiver has a bit error rate (BER) of less than 0.001 and a data rate of 100 Mbps. The simulation results of the proposed circuit show a 26.4 dB gain (S21), a-39 dB input return loss (S11) and a 5.22 dB noise figure (NF). The simulation results are in good agreement with the analytical calculations.
 
Article
Usually, in the studies of optimal control for the micro-grid with combined heat and power (CHP), economic and environmental goals have been raised. In these studies, the optimization of control devices and compensators that are aimed at improving the technical aspects of micro-grid has not been considered. Therefore, in this paper, these goals are considered simultaneously. In this paper the shunt capacitor, shunt reactor, static var compensator, load ratio control transformer, step voltage regulator and power generation of DGs are investigated as control variables with the aim of considering costs, losses and voltage profile improvement. The case under study is a distribution test system including 22 buses, which consists of photovoltaic and fuel cell. All network data is extracted from a real system. As a result, the system can completely represent a real system. In order to complete the study of the system, the emissions of fuel cells are considered in the objective function. The efficiency and output electrical and thermal power of the fuel cell are considered related to part load ratio as a real standard model introduced in previous studies.
 
Article
Videos are made up of a temporal sequence of frames and are projected at a proper rate to create the illusion of motion. This means that there exists a high correlation between adjacent temporal frames so that when projected at a proper rate, smooth motion is seen. Correlation between adjacent temporal frames is called interframe correlation. In order to decode compressed video bit stream uniformly by various platforms and devices, the bit stream format must be predefined. Thus, there must be a standard for a video compressor, which will enable all standard-compliant compressed video data to be decoded anywhere. The goal is to propose a new video compression algorithm based on wavelet transform and neural networks. Using wavelet transform leads to factorization in temporal as well as spatial domain. The goal in this paper is to achieve a compression algorithm which would be faster and has more compression ratio. Neural networks are used for prediction which is one of the most important functions in any video compression scheme. Furthermore, the proposed algorithm is compared with MPEG standard. Simulation results show the benefits of using wavelet transform which reveal that the proposed algorithm is faster and has better performance in some aspects compared to MPEG standard. The video which obtained from proposed algorithm is acceptable regarding human vision. Since it needs less space for storing, it is suitable for portable devices.
 
Article
This paper presents, a novel evolutionary method for dynamic feeder reconfiguration at the presence of distributed generators (DGs), energy storage (ES) units and solar photovoltaic (PV) panels. Modern distribution networks, in addition to the importance of economic issues, must operate at an acceptable level of system reliability, Failure to pay attention to the reliability importance can lead to irreparable damages in the distribution network. Regarding the importance of the objective functions including voltage stability index (VSI), energy loss and energy not supplied (ENS) has led to the presentation of a stochastic multi-objective framework for dynamic feeder reconfiguration in the presence of distributed generators (DGs), energy storage (ES) units and solar photovoltaic (PV) panels considering uncertainty of PV units. A modified shuffled frog leaping algorithm is provided in this study to solve the proposed optimization problem. In order to show the efficiency and supremacy of the proposed method is applied on 33-node test system.
 
Article
This paper describes an optimal design for multivariable PI controller with a high gain structure for an irregular system by genetic algorithm. PI controllers with a high gain structure leads to the asymptotic decomposition of the fast and slow modes in the closed loop system that have unique characteristics. The slow modes are asymptotically uncontrollable and unobservable; therefore, they have not role in input and output behavior. The closed-loop response is affected only from rapid poles; therefore, the system response will have quick behavior. An essential requirement of this design is that the first Markov parameter of multivariable system (the matrix product CB) must have full rank. If the CB matrix is not full rank, the measurement matrix (M) is used with internal feedback. In this structure, the measurement matrix is chosen using genetic algorithm in order to reach the stable closed-loop system and minimize interference between outputs. The research is implemented on the two kind of different systems. The results show that the response time of PI controller with a high gain structure by genetic algorithms has good behavior in comparison with other methods.
 
Article
This paper describes an optimal design for multivariable PI controller with a high gain structure for an irregular system by genetic algorithm. PI controllers with a high gain structure leads to the asymptotic decomposition of the fast and slow modes in the closed loop system that have unique characteristics. The slow modes are asymptotically uncontrollable and unobservable; therefore, they have not role in input and output behavior. The closed-loop response is affected only from rapid poles; therefore, the system response will have quick behavior. An essential requirement of this design is that the first Markov parameter of multivariable system (the matrix product CB) must have full rank. If the CB matrix is not full rank, the measurement matrix (M) is used with internal feedback. In this structure, the measurement matrix is chosen using genetic algorithm in order to reach the stable closed-loop system and minimize interference between outputs. The research is implemented on the two kind of different systems. The results show that the response time of PI controller with a high gain structure by genetic algorithms has good behavior in comparison with other methods.
 
Article
Recent efforts to increase the power transmission capacity and increase the level of network stability have increased the use of Flexible AC Transmission Systems elements in the power system. The protective system, which is one of the most important parts of the power system's operation, is seriously affected by these devices, so their study is considered necessary. Among protection relays, the protection of the distances due to high speed, proper operation in different network conditions are used as the main protection of transmission lines. Consequently, it is inevitable that the lines compensated by flexible AC systems are protected by long-range relays. In this paper, the Distributed Power Flow Controller has been investigated and simulated, and then the effect of these devices on the measured impedance and the characteristic of the disturbance relay is shown. It is also shown in this paper that in addition to the effects of the relay seen on the relay due to changes in the power system, the type of control system and the adjustment of the parameters of these devices will have different effects on the impedance seen by the relay. To investigate the effect of controller distributed power distribution on the protection of the energy transmission distances, as well as the effect of the impedance seen on the relay due to the presence and type of control system that the distributed power controller works with, it uses the PSCAD / EMTDC software for the model These compensator have been used.
 
The conductors in the calculation space, for TE polarization, zero components of the electric field the cells inside the conductor space (gray squares).
Box color used to draw the vertical component of the electric field ( ) y E Fig. (6)
Path loss versus range at 20 m altitude computed using FDTD over the PEC obstacles
Article
In this paper, we implement real irregular terrain model in computer program by using image processing. We show how this approach can be used in simulation of E.M. wave propagation on irregular earth’s surface in a realistic manner. Some simulations are performed for implementation of longitudinal height differences over the propagation path as PEC surface .We also describe that how this approach can be used for any boundary condition in computational space. The results observed in Snapshots of the field profiles taken at different simulation times, validates capability of this method.
 
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Taking advantage of advances in Nanotechnology, the quantum-dot cellular automata (QCA) has overcome many limitations that complementary metal-oxide-semiconductor (CMOS) had been confronted. Undesirable characteristics such as too many leakage currents limit the CMOS designs in nano dimensions. The idea of designing multiple-valued logic (MVL) systems rather than standard binary has gotten attractive to many designers. The application of MVL in the design of digital circuits offers so many advantages over traditional methods. D flip-flop is a primary sequential circuit in any register. In this paper, a novel quaternary D flip-flop based on introducing quaternary QCA (QQCA) is presented. The structure of our quaternary model is clarified. Also, we have proposed a 4-qubits register by utilizing the presented quaternary D flip-flop. Both circuits got simulated and evaluated by QCASim (quaternary edition). QCASim can illustrate the simulation result in a truth table and a waveform format. Our work got compared with other published works. The simulation results show that our proposed circuit is efficient in terms of latency and energy consumption. Keywords: quaternary quantum-dot cellular automata, quaternary logic, quaternary D flip-flop, quaternary register, QCASim.
 
Article
In this paper, a new approach (not new technique) is introduced for designing frequency selective surfaces (FSSs). We try to compose the desired frequency response using the frequency response of each constituent FSS. Also, a new dual-band miniaturized frequency selective surface is proposed. In contrast to the conventional FSS design technique, the presented structure takes advantage of non-resonance elements and has unit cells with a miniaturized dimension. The proposed FSS cells are composed of two complex and inductive planes that act as a dual-band filter through the pass of electromagnetic wave propagation. The performance of this structure toward various angles of incident waves and different polarizations is stable.
 
Article
Selecting optimal features based on nature of the phenomenon and high discriminant ability is very important in the data classification problems. Since it doesn't require any assumption about stationary condition and size of the signal and the noise in Recurrent Quantification Analysis (RQA), it may be useful for epileptic seizure Detection. In this study, RQA was used to discriminate ictal EEG from the normal EEG where optimal features selected by combination of algorithm genetic and Bayesian Classifier. Recurrence plots of hundred samples in each two categories were obtained with five distance norms in this study: Euclidean, Maximum, Minimum, Normalized and Fixed Norm. In order to choose optimal threshold for each norm, ten threshold of ε was generated and then the best feature space was selected by genetic algorithm in combination with a bayesian classifier. The results shown that proposed method is capable of discriminating the ictal EEG from the normal EEG where for Minimum norm and 0.1˂ε˂1, accuracy was 100%. In addition, the sensitivity of proposed framework to the ε and the distance norm parameters was low. The optimal feature presented in this study is Trans which it was selected in most feature spaces with high accuracy.
 
Article
Fault detection and diagnosis algorithms are methods whose function is determining the fault point in a system according to pre-faulting and post-faulting conditions, and fault detector is a part of system which performs this function. Accordingly, the aspects like fault detection and diagnosis and faulted point isolation have been introduced. Until now many researches have focused on fault detection methods in different parts of power system such as transformers, converters, overhead lines, underground cables, feeders, breakers, protection relays, generators, turbines, etc., which every one of them has proposed a new and effective method in supplementing of previous works. In this paper, a comprehensive study is done on fault detection and diagnosis in distribution power systems. Also, categorizing and also methodology of previous works in literature is addressed. Fault detection and diagnosis algorithms are divided based on two viewpoints and characteristics and features of each one are described completely.
 
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Numerous methods have been introduced for digital images watermarking as well as rubosting them. In this method, with using Graph-based transform and extracts the best graph structure with genetic algorithm so that watermarking can be performed with maximum robustness. One of the common methods in watermarking robustness is the use of discrete cosine transform (DCT). In this study, we have shown that the proposed method is much more powerful than DCT. The proposed method is tested on five different color images such as Lena, Barbara, Boat, Baboon, Peppers. Watermark image (logo) is a random binary image with size 16 x 16 and 8 x 8 pixels. This simulation results show that the proposed method is more robust to similar methods such as the DCT. Proposed Watermarking has been evaluated using Bit Error Rate (BER), Structural Similarity Index Measuring (SSIM) and Peak signal-to-noise ratio (PSNR) criteria and different strength Gaussian noise attacks, JPEG compression, median filter, bluring, rescaling, rotation and cropping attacks. به منظور نهان‌نگاری اطلاعات در تصاویر دیجیتال و همچنین مقاوم‌سازی آنها روش‌های متعددی تاکنون معرفی شده است. در این روش از تبدیل گراف محور استفاده شده است و به کمک الگوریتم ژنتیک بهترین ساختار گراف استخراج می‌شود به طوری که نهان‌نگاری با بیشترین مقاومت در برابر حملات انجام شود. یکی از روش‌های مرسوم در مقاوم‌سازی نهان‌نگاری استفاده از تبدیل کسینوسی گسسته است. در این تحقیق نشان داده‌ایم که روش پیشنهادی بسیار قدرتمندتر از تبدیل کسینوسی گسسته است. برای آزمایش روش پیشنهادی از تصاویر معروف ‌لنا، ‌باربارا، بابون، قایق و فلفل استفاده شده است و نتایج حاصل از شبیه‌سازی هر دو تبدیل به خوبی نشان می‌دهند که روش پیشنهادی مقاومت بیشتری نسبت به روش‌های مشابه مانند روش‌های مبتنی بر تبدیل کسینوسی گسسته دارد. در این شبیه‌سازی تصویر نهان‌نگار یک لوگوی تصادفی با ابعاد 8×8 و 16×16 است. نهان‌نگاری به کمک معیارهای نرخ خطای بیت، معیار اندازه‌گیری شباهت ساختاری و نسبت دامنه سیگنال به نویز و حملات نویز گاوسی با شدت‌های مختلف، فشرده‌سازی، فیلترمیانه، تاری، تغییر اندازه، چرخش و برش مورد ارزیابی قرار گرفته است.
 
The sphere of influence [16]
The proposed Earthing design
Initialized Mesh Model  
The potential distribution on the soil surface and in a plate with a depth of 0.5 m.
The potential distribution on the soil surface and in a rod surface with a depth of 1 m.  
Article
Protection of equipment, safety of persons and continuity of power supply are the main objectives of the grounding system. For its accurate design, it is essential to determine the potential distribution on the earth surface and the equivalent resistance of the system. The knowledge of such parameters allows checking the security offered by the grounding system when there is a failure in the power systems. A new method to design an earthing systems using Finite Element Method (FEM) is presented in this article. In this approach, the influence of the moisture and temperature on the behavior of soil resistivity are considered in EARTHING system DESIGN. The earthing system is considered to be a rod electrode and a plate type electrode buried vertically in the ground. The resistance of the system which is a very important factor in the design process is calculated using FEM. FEM is used to estimate the solution of the partial differential equation that governs the system behavior. COMSOL Multiphysics 4.4 which is one of the packages that work with the FEM is used as a tool in this design. Finally the values of the resistance obtained by COMSOL Multiphysics are compared with the proven analytical formula values for the ground resistance, in order to prove the work done with COMSOL Multiphysics.
 
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The WiMAX mesh network based IEEE 802.16 standard provides maximum using of the bandwidth channel. Mesh WiMAX network is a promising technology by offering high data rate, broadband wireless access, high quality of service and large coverage area with the low cost of deployment. One of the most important issues in the WiMAX network is the failure of subscriber stations due to less power or mobility or etc during the relay multi hop transmission path so that knowing of the fault tolerant parameters such as connection resilience has received much attention recently. In this paper, we propose an analytical framework to estimate the connction availability and connection resilience for one node based on the Continuous Time Markov Chain (CTMC) using multiple back up nodes for the selection of sponsor nodes. The multiple backup sponsor node technique enhances the fault tolerance of network in front of failure of sponsor nodes. We also develop the analytical framework to analyze the connection resilience among subscriber stations in the mesh cluster. Knowing of the connection resilience improves the requirements of succeful transmission.
 
Article
The sympathetic Inrush current that occurs in series and parallel transformers can cause the creation of two major problems in the protection of power transformers. The main problem is that the peak of the inrush current for this case is more severe rather than common inrush current that the protection system may mal-operate. Besides, when a common protection system is designed for parallel transformers, the line input current, the vector summation of the input currents, will be detected as a single-phase fault that can cause the incorrect operation of the protection system. For this purpose, this paper presents a novel approach based on Lissajous of current signal for detection of inrush current phenomenon. The proposed method detects the faults very quickly; as well as, this method has appropriate operation under noisy conditions, like white Gaussian noise. This method is evaluated using a network consist of 230 to 63 kV parallel transformers with vector group ynd11. The results show that the proposed method performs better than conventional industrial schemes, such as second harmonic, zero-crossing, and waveform analysis method.
 
Symbol and equivalent circuit of 2–input n–type FGMOS  
The proposed OTA using FGMOS inverters; (a) schematic, (b) symbol  
Schematic of proposed 2-order G m -C filter  
Frequency tuning of the proposed 2-order G m-C filter for low-pass response
Article
In this paper, a low voltage and low power (LV/LP) Operational Transconductance Amplifier (OTA) using FGMOS (Floating-Gate MOS) transistor is proposed. The relative tuning range of 50 is achieved in this OTA while only consumes 40 µW with 1.0 V supply voltage in TSMC 0.18 µm CMOS technology. The simulation results of the proposed OTA show an open loop gain of 30.2 dB and a unity gain frequency of 942 MHz. In comparison with previous works, the proposed OTA, with lower supply voltage, is provided the better frequency performance, higher output voltage swing, better linearity and lower power consumption. The proposed OTA is used in the second-order filter to show a good tuning range from 100 kHz to 5.6 MHz which is suitable for the wireless specifications of Bluetooth (650 kHz),CDMA2000 (700 kHz) and Wideband CDMA (2.2 MHz). The active area occupied by the designed filter on silicon is .
 
Article
In modern and big greenhouses, it is necessary to measure several climate parameters to automate and control the greenhouse properly. Monitoring and transmitting by cable may lead to an expensive and stiff measurement system. Since, Wireless Sensor Network (WSN) is a distributed system that consists of small size wireless sensor nodes equipped with radio and one or several sensors; it is a low cost option to build the required monitoring system. In this paper, we introduce and implement an intelligent monitoring system based on WSN by using Xbee modules. The Xbee Series 2 hardware uses a microchip from Ember Networks that enables several different flavors of standards-based ZigBee mesh networking. All gathered information by sensors, are sent to a remote center in form of GPRS packets through a GSM network and viewed by monitoring software. The proposed system has low power consumption, low cost and simple driver circuits. Furthermore, it can support various types of digital and analog sensors.
 
Article
Memristor is the fourth fundamental element after resistor, capacitor, and inductor. Memristor can become an essential element of SRAM and DRAM caches because of its zero power consumption in data storage and non-volatile state. It can effectively improve the efficiency, speed, and power consumption of circuits. In this paper, we propose a 4T1M memory cell reducing the cell area by maintaining the maximum properties of 6T1M. To simulate the proposed memory cell, the length of the memristors is 10 nm, and the resistance of their on and off states is selected as 1 kΩ and 200 kΩ, respectively. Also, the cell MOS transistors are simulated by the 32 nm HP CMOS PTM model. Simulations in H-Spice software, at 0.9 V power supply, have been conducted to compare the proposed cell characteristics with two conventional six-transistor (6T) and six-transistor one-memristor (6T1M) cells. The results show that using a memristor in a memory cell causes zero power consumption during data storage for a long time and reduces the occupied area by 36.7% compared to the 6T1M cell. The speed of writing "1" data on the proposed cell is only 30 ps, which shows a 3-fold improvement compared to the 6T1M cell, but no significant change is observed when writing "0" data. The static power of the proposed cell is 133 times less than that of a six-transistor cell, and its dynamic power is about the same as the 6T1M cell, but it consumes 60 times less energy than a six-transistor cell.
 
Article
Recently, much attention has been paid to Vehicular Ad hoc Network (VANET). VANETs address direct communication between vehicle-to-vehicle and vehicles to roadside units (RSUs). They are similar to the Mobile and Ad hoc Networks (MANET) in their rapid and dynamic network topology changes due to the fast motion of nodes. High mobility of nodes and network resources limitations have made the routing, one of the most important challenges in VANET researches. Therefore, guaranteeing a stable and reliable routing algorithm over VANET is one of the main steps to realize an effective vehicular communications. In this paper, a two-step AODV-based routing protocol is proposed for VANET networks. At first, node-grouping is done using their mobility information such as speed and movement direction. If the first step cannot respond efficiently, the algorithm enters the second step which uses link expiration time (LET) information in the formation of the groups. The goal of the proposed protocol is increasing the stability of routing algorithm by selecting long-lived routes and decreasing link breakages. The comparison of proposed algorithm with AODV and DSR protocols is performed via the Network Simulator NS-2. It is shown that the proposed algorithm increases the delivery ratio and also decreases the routing control overhead.
 
Article
در این مقاله نسخه جهش یافته دینامیکی الگوریتم بهینهسازی گرگ خاکستری برای حل مسئله پخش بار اقتصادی - زیستمحیطی سیستم قدرت استاندارد 40 واحدی به همراه دو مزرعه بادی پیشنهاد شده است. لذا تابع هدفی جامع از هزینه- های بهرهبرداری که ترکیبی از هزینههای مستقیم انرژی باد، هزینه جریمه تخمین بیش از حد، هزینه جریمه تخمین کمتر از حد، هزینه واحد حرارتی و هزینه آلایندگی، ارائه شده است. با توجه به ماهیت تصادفی سرعت باد توان تولیدی توسط توربین- های بادی غیرقابل پیشبینی است، بنابراین از تابع توزیع احتمال ویبول برای مدلسازی توان مزرعههای باد در این مقاله استفاده شده است. هزینه بهرهبرداری مزرعه بادی بهصورت احتمالاتی در نظر گرفته شده است تا سناریوهای باد با احتمال پایین تاثیر کمتری در هزینه نهایی داشته باشند. شبیهسازیها در قالب سه بخش انجام شده است و بهمنظور اعتبارسنجی با مرجعهای دیگر مورد مقایسه واقع شده است. نتایج حاصل شده از بهینهسازیها در هر سه سناریو و مقایسه آن با الگوریتمهای هوشمند تائیدی بر عملکرد بهتر و دقت بالاتر الگوریتم پیشنهادی نسبت به نسخه اصلی الگوریتم گرگ خاکستری و همچنین سایر الگوریتمها دارد.
 
Top-cited authors
Elham Mokaramian
  • University of Mohaghegh Ardabili
Ali Ahmadpour
  • University of Mohaghegh Ardabili
Hossein Shayeghi
  • University of Mohaghegh Ardabili
Sajad Samadinasab
  • Iran University of Science and Technology
Seyed-Jalal Seyed-Shenava
  • University of Mohaghegh Ardabili