Iran University of Science and Technology (IUST) Iranian Journal of Electrical and Electronic Engineering 1735-2827 1735-2827 7 2 2011 6 1 Neuro-ANFIS Architecture for ECG Rhythm-Type Recognition Using Different QRS Geometrical-based Features 70 83 EN M. R. Homaeinezhad mrezahomaei@yahoo.com Y E. Tavakkoli ehsan.tavakkoli@yahoo.com N A. Afshar ali_f_sme@yahoo.com N A. Atyabi abbasatyabi@yahoo.com N A. Ghaffari ghaffari@kntu.ac.ir N The paper addresses a new QRS complex geometrical feature extraction technique as well as its application for electrocardiogram (ECG) supervised hybrid (fusion) beat-type classification. To this end, after detection and delineation of the major events of ECG signal via a robust algorithm, each QRS region and also its corresponding discrete wavelet transform (DWT) are supposed as virtual images and each of them is divided into eight polar sectors. Then, the curve length of each excerpted segment is calculated and is used as the element of the feature space. To increase the robustness of the proposed classification algorithm versus noise, artifacts and arrhythmic outliers, a fusion structure consisting of three Multi Layer Perceptron-Back Propagation (MLP-BP) neural networks with different topologies and one Adaptive Network Fuzzy Inference System (ANFIS) were designed and implemented. To show the merit of the new proposed algorithm, it was applied to all MIT-BIH Arrhythmia Database records and the discrimination power of the classifier in isolation of different beat types of each record was assessed and as the result, the average accuracy value Acc=98.27% was obtained. Also, the proposed method was applied to 8 number of arrhythmias (Normal, LBBB, RBBB, PVC, APB, VE, PB, VF) belonging to 19 number of the aforementioned database and the average value of Acc=98.08% was achieved. To evaluate performance quality of the new proposed hybrid learning machine, the obtained results were compared with similar peer-reviewed studies in this area. Feature Extraction,Curve Length Method,Multi Layer Perceptron,Adaptive Network Fuzzy Inference System,Fusion (Hybrid) Classification,Arrhythmia Classification,Supervised Learning Machine, http://ijeee.iust.ac.ir/article-1-328-en.html http://ijeee.iust.ac.ir/article-1-328-en.doc

Iran University of Science and Technology (IUST) Iranian Journal of Electrical and Electronic Engineering 1735-2827 1735-2827 7 2 2011 6 1 Image Restoration with Two-Dimensional Adaptive Filter Algorithms 84 105 EN M. Shams Esfand Abadi Shahid Rajaee University shamsiaeste2003@yahoo.com Y S. Nikbakht Shahid Rajaee University sr_nikbakht@yahoo.com N Two-dimensional (TD) adaptive filtering is a technique that can be applied to many image, and signal processing applications. This paper extends the one-dimensional adaptive filter algorithms to TD structures and the novel TD adaptive filters are established. Based on this extension, the TD variable step-size normalized least mean squares (TD-VSS-NLMS), the TD-VSS affine projection algorithms (TD-VSS-APA), the TD set-membership NLMS (TD-SM-NLMS), the TD-SM-APA, the TD selective partial update NLMS (TD-SPU-NLMS), and the TD-SPU-APA are presented. In TD-VSS adaptive filters, the step-size changes during the adaptation which leads to improve the performance of the algorithms. In TD-SM adaptive filter algorithms, the filter coefficients are not updated at each iteration. Therefore, the computational complexity is reduced. In TD-SPU adaptive algorithms, the filter coefficients are partially updated which reduce the computational complexity. We demonstrate the good performance of the proposed algorithms thorough several simulation results in TD adaptive noise cancellation (TD-ANC) for image restoration. The results are compared with the classical TD adaptive filters such as TD-LMS, TD-NLMS, and TD-APA Two Dimensional,Adaptive Filter,Noise Cancellation,Selective Partial Update,Variable Step-Size,Set-Membershi, http://ijeee.iust.ac.ir/article-1-344-en.html http://ijeee.iust.ac.ir/article-1-344-en.doc

Iran University of Science and Technology (IUST) Iranian Journal of Electrical and Electronic Engineering 1735-2827 1735-2827 7 2 2011 6 1 Power Allocation Strategies for MIMO Radar Waveform Design 106 111 EN A. Merline Department of ECE, Sethu Institute of Technology a_merline@yahoo.co.in Y S. J. Thiruvengadam Tifac Core on Wireless Technologies, Thiagarajar College of Engineering, sjtece@tce.edu.in N The role of waveform design is central to effective radar resource management for state-of-the art radar systems. The waveform shape employed by any radar system has always been a key factor in determining the performance and application. The design of radar waveform to minimize mean square error (MSE) in estimating the target impulse response is based on power allocation using waterfilling. This paper shows the effect of various power control strategies in the MMSE performance of the waveform design. We find that the truncated power control strategy exhibits a good MMSE performance. The performance improvement results from the fact that with the truncated power control no power is wasted in poor quality modes. Truncated Power Control,MIMO Radar,Waterfilling, http://ijeee.iust.ac.ir/article-1-274-en.html http://ijeee.iust.ac.ir/article-1-274-en.doc

Iran University of Science and Technology (IUST) Iranian Journal of Electrical and Electronic Engineering 1735-2827 1735-2827 7 2 2011 6 1 A Novel Hybrid Nano Scale MOSFET Structure for Low Leak Application 112 121 EN A. Rana NIT Hamirpur ashwani_paper@yahoo.com Y N. Chand NIT Hamirpur nar@nitham.ac.in N V. Kapoor NIT Hamirpur kapoor@nitham.ac.in N In this paper, novel hybrid MOSFET(HMOS) structure has been proposed to reduce the gate leakage current drastically. This novel hybrid MOSFET (HMOS) uses source/drain-to-gate non-overlap region in combination with high-K layer/interfacial oxide as gate stack. The extended S/D in the non-overlap region is induced by fringing gate electric field through the high-k dielectric spacer. The gate leakage behaviour of HMOS has been investigated with the help of compact analytical model and Sentaurus Simulation. The results so obtained show good agreement between model and simulation data. It is found that HMOS structure has reduced the gate leakage current to great extent as compared to conventional overlapped MOSFET structure. Further, the proposed structure had demonstrated improved on current, off current, subthreshold slope and DIBL characteristic. Hybrid MOSFET(HMOS),Gate Tunneling Current,Analytical Model,Spacer Dielectrics,DIBL,Subthreshold Slope, http://ijeee.iust.ac.ir/article-1-357-en.html http://ijeee.iust.ac.ir/article-1-357-en.doc

Iran University of Science and Technology (IUST) Iranian Journal of Electrical and Electronic Engineering 1735-2827 1735-2827 7 2 2011 6 1 Band Structures for 2D Photonic Crystals in Presence of Nonlinear Kerr Effect ‎Calculated by Use of Nonlinear Finite Difference Time Domain (NFDTD) Method‎ 122 130 EN A. Khodabakhsh TARBIAT MODARES UNIVERSITY amir.khodabakhsh@gmail.com N M. K. Moravvej-Farshi TARBIAT MODARES UNIVERSITY farshi_k@modares.ac.ir Y M. Ebnali-Heidari Sharekord University Ebnali-m@eng.sku.ac.ir N We report the simulation results for impact of nonlinear Kerr effect on band structures of a ‎two dimensional photonic crystal (2D-PhC) with no defect, a PhC based W1-waveguide ‎‎(W1W), and also Coupled-Cavity Waveguides (CCWs). All PhC structres are assumed to a ‎square lattice of constant a made of GaAs rods of radius r=0.2a, in an air background. The ‎numerical simulation was performed using the nonlinear finite difference time domain ‎‎(NFDTD) technique. To study the impact of Kerr effect on the photonic band structures, E-‎polarized lights of peak input intensities 0.5 GW-cm−2≤I≤25 GW-cm−2 have been used. The ‎numerical results have shown that as the input light intensity increases, the band edges for all ‎PhC waveguide structures considered experience red shifts. These numerical results for CCWs ‎also show that the larger the light input intensity, the smaller is the corresponding maximum ‎light group velocity.‎ Photonic Crystal (PhC),Nonlinear Kerr Effect,Photonic Band Structures,Dispersion Curve,Waveguides, http://ijeee.iust.ac.ir/article-1-350-en.html http://ijeee.iust.ac.ir/article-1-350-en.doc

Iran University of Science and Technology (IUST) Iranian Journal of Electrical and Electronic Engineering 1735-2827 1735-2827 7 2 2011 6 1 A Novel Index for Online Voltage Stability Assessment Based on Correlation Characteristic of Voltage Profiles 131 140 EN M. R. Aghamohammadi Power & Water University of Technology Aghamohammadi@pwut.ac.ir Y S. Hashemi Power & Water University of Technology sina_hashemi_86@yahoo.com. N M. S. Ghazizadeh Power & Water University of Technology ghazizadeh@pwut.ac.ir N Abstract: Voltage instability is a major threat for security of power systems. Preserving voltage security margin at a certain limit is a vital requirement for today’s power systems. Assessment of voltage security margin is a challenging task demanding sophisticated indices. In this paper, for the purpose of on line voltage security assessment a new index based on the correlation characteristic of network voltage profile is proposed. Voltage profile comprising all bus voltages contains the effect of network structure, load-generation patterns and reactive power compensation on the system behaviour and voltage security margin. Therefore, the proposed index is capable to clearly reveal the effect of system characteristics and events on the voltage security margin. The most attractive feature for this index is its fast and easy calculation from synchronously measured voltage profile without any need to system modelling and simulation and without any dependency on network size. At any instant of system operation by merely measuring network voltage profile and no further simulation calculation this index could be evaluated with respect to a specific reference profile. The results show that the behaviour of this index with respect to the change in system security is independent of the selected reference profile. The simplicity and easy calculation make this index very suitable for on line application. The proposed approach has been demonstrated on IEEE 39 bus test system with promising results showing its effectiveness and applicability. Voltage Security Margin,Voltage Profile,Pattern Recognition,Correlation,Load Pattern, http://ijeee.iust.ac.ir/article-1-237-en.html http://ijeee.iust.ac.ir/article-1-237-en.doc

Iran University of Science and Technology (IUST) Iranian Journal of Electrical and Electronic Engineering 1735-2827 1735-2827 7 2 2011 6 1 Load-Frequency Control: a GA based Bayesian Networks Multi-agent System 141 148 EN F. Daneshfar University of Kurdistan daneshfar@ieee.org Y H. Bevrani University of Kurdistan bevrani@ieee.org N F. Mansoori University of Kurdistan Fathollah.mansoori@yahoo.com N Bayesian Networks (BN) provides a robust probabilistic method of reasoning under uncertainty. They have been successfully applied in a variety of real-world tasks but they have received little attention in the area of load-frequency control (LFC). In practice, LFC systems use proportional-integral controllers. However since these controllers are designed using a linear model, the nonlinearities of the system are not accounted for and they are incapable to gain good dynamical performance for a wide range of operating conditions in a multi-area power system. A strategy for solving this problem due to the distributed nature of a multi-area power system, is presented by using a BN multi-agent system. This method admits considerable flexibility in defining the control objective. Also BN provides a flexible means of representing and reasoning with probabilistic information. Efficient probabilistic inference algorithms in BN permit answering various probabilistic queries about the system. Moreover using multi-agent structure in the proposed model, realized parallel computation and leading to a high degree of scalability. To demonstrate the capability of the proposed control structure, we construct a BN on the basis of optimized data using genetic algorithm (GA) for LFC of a three-area power system with two scenarios. Load-Frequency Control,Multi-Agent System (MAS),Bayesian Network, http://ijeee.iust.ac.ir/article-1-345-en.html http://ijeee.iust.ac.ir/article-1-345-en.doc