ISSN: 1998-4464



Year 2008

All papers of the journal were peer reviewed by two independent reviewers. Acceptance was granted when both reviewers' recommendations were positive.
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    Paper Title, Authors, Abstract (Issue 1, Volume 2, 2008)


Comparative Study of Chebyshev I and Chebyshev II Filter used For Noise Reduction in ECG Signal
Mahesh S. Chavan, RA.Agarwala, M.D.Uplane

Abstract: Signal processing, in general, has a rich history, and its importance is evident in diverse fields as biomedical engineering, acoustics, Sonar. The importance of the digital signal processing appears to be increasing with no visible sign of saturation. The impact of digital signal processing techniques will undoubtedly promote revolutionary advances in some fields of application. A notable example is in the area telephony, medicine. In many medical application, there is need to remove frequency components from a signal while leaving rest of spectrum unaltered. While recording ECG signal it gets corrupted due to different noise interferences and artifacts. Noise and interference are usually large enough to obscure small amplitude features of the ECG hat are of physiological or clinical interest. The bandwidth of the noise overlaps that of wanted signals, so that simple filtering cannot sufficiently enhance the signal to noise ratio. The present paper introduces the digital filtering method to cope with the noise artifacts in the ECG signal. The Chebyshev I and Chebyshev type II filters are applied on the ECG signal. The detailed design procedure with there responses are depicted in the paper. This article also gives the comparison of both types of the filter. It is found that both digital filters works satisfactory with some limitations. All the designs are implemented using MATLAB FDA tool. ECG data is acquired from the Instrumentation amplifier designed in the Laboratory. For the interfacing of ECG amplifier to the computer advantech 711B add on card has been used. Results of the filter are compared with other filters also.


HRV analysis using wavelet package transform and Least Square Support Vector Machine
Gley Kheder, Abdennaceur Kachouri and Mounir Samet

Abstract: In this study we are interested in the feature extraction of HRV which includes Ventricular Fibrillation (VF) and ventricular tachycardia (VT) and its classification by the least square support vector machine (LS-SVM). In the first stage, we are interested in the demonstration of the efficacity of the signals? analysis HRV by WPT compared to the analysis by DWT. Since the DWT analysis of the HRV causes frequency decomposition. In this study we are going to present new solution using WPT to decompose the HRV signal into HF and LF frequency ranges. The obtained frequency bands are too close to LF and HF bands. RMS measure the signal power contained in the specified frequency bands LF and HF. The index of sympathovagal balance (LF/HF) was examined by RMS of wavelet coefficients. The second part is devoted to evaluating the performance of the features extraction method using the outputs towards an LS-SVM classification algorithm. The classifications include exploratory data analysis, optimal input variable selection, parameter estimation, and performance evaluation via Receiver Operating Characteristic (ROC) curve analysis. LS-SVM model with Radial Basis Function (RBF) kernel achieve a best performance.


Steady State Operation of Self-Excited Induction Generator with Varying Wind Speeds
K.S. Sandhu and S.P. Jain

Abstract: In contrast to conventional generators, self-excited induction generators are found to be most suitable machines for wind energy conversion in remote and windy areas due to many advantages over grid connected machines. However such machines exhibits poor performance in terms of voltage and frequency under frequent variations of operating speeds, which is a common feature in wind energy conversion. In this paper an attempt has been made to present a simple model to control the output voltage and frequency in case of self-excited induction generator under such operating conditions. It is realized that rotor resistance control for a wound rotor machine results in to a constant voltage constant frequency operation. Simulated results as obtained have been compared with experimental results on two test machines and found to be in close agreement.


Estimating Wideband Polynomial Phase Signals in Sensor Arrays Using the Extended Kalman Filter
A. Ouldali, S. Sadoudi, and Z. Messaoudi

Abstract: In the present paper, we consider the problem of parameter estimation of wideband polynomial phase signals (PPS) impinging on a uniform linear array antenna. The parameters of interest are the polynomial phase coefficients and the direction of arrival of the signal. The principle of estimation is based on the introduction of an exact but unfortunately nonlinear state space modelization, of the wideband PPS, which compels us to use the extended Kalman filter (EKF) instead of the usual Kalman filter. Furthermore, we propose a solution to the problem of initialization of the EKF since the initial conditions are assumed to be unavailable. The proposed solution is based on the use of the high-order ambiguity function, generally used to estimate PPS, and the Cramer-Rao bounds. Under this solution, the numerical simulations show that the use of the EKF improves existing methods in terms of statistical performances since the EKF-based estimators exhibit high performances.


Hall Effect Sensor and Artificial Neural Networks Application in Current Transformer
G.Gokmen, Y.Ozel, N.Ekren

Abstract: Nowadays, The open loop and closed loop Hall Effect Current transformers are being widely used for industrial applications because of AC, DC and complex waveform current measurement capability. Current, power, magnetic field and distance sensing and measurement are the most important application fields. Especially, it facilities the flux density sensing of the magnetic material inside for which the flux density measurement is very difficult. In this study, linear Hall Effect sensor based closed loop current measurement was carried out. The relationship between input and output parameters (Primary MMF and measurement voltage) of The Hall Effect current transformer was examined and estimation of measurement voltage was carried out by means of the artificial neural network.. When estimation results are compared to measurement values, it is shown that the artificial neural network model produces reliable estimates of measurement voltage of a Hall Effect current transformer.


A Single-Phase Grid-Co nected PV System With Active Power Filter
Denizar C. Martins and Kleber C. A. de Souza

Abstract: In this paper a single-phase active power filter based in a two stages grid-connected photovoltaic system is presented. The proposed system can not only inject PV power into utility but can act always as an active power filter to compensate the load harmonics and reactive power such that the input power factor is unity independently of the solar radiation. In sunny days, the system processes all the reactive and active load power and the excessive power from the PV module can be fed to the utility. On the other hand, on cloudy days for instance, if the PV power is not enough, the system processes all the reactive load power and the shortage of load active power is supplemented by the utility. Besides, just using one current sensor, the control strategy is simpler and of easy practical implementation.


Formal Verification of Superscalar Microarchitectures: Functional approach
S. Merniz, and M. Benmohammed

Abstract: Verifying a pipelined Micro-Architectural (MA) implementation against an Instruction-Set-Architecture (ISA) specification is a common approach which still requires considerable efforts because there is no meaningful point where the implementation state and the specification state can be compared easily. An alternative approach consists of verifying a pipelined micro-architectural implementation against a sequential multi-cycle implementation. Because both models are formalised in terms of clock cycles, all synchronous intermediate states represent useful points where the comparison could be achieved easily. Also, because both models relate to the MA level, there is no need for a data abstraction function, only a time abstraction function is needed to map between the times used by the two models. A major advantage of this elegant choice is the ability to carry out the proof by induction within the same specification language rather than by symbolic simulation through a proof tool which remains very tedious. Furthermore, by decomposing the state, the overall proof decomposes systematically into a set of verification conditions more simple to reason about and to verify. The proposed proof methodology is illustrated on both the pipelined and the superscalar pipelined MIPS processors within Haskell framework.


An efficient nonstationary Wiener filter hardware implementation
Veselin N. Ivanovi?, Srdjan Jovanovski

Abstract: An efficient multicycle hardware design of a nonstationary (time-varying (TV)) Wiener filter, based on timefrequency (TF) analysis, is considered. It is developed by following the idea of a new method for filter?s region of support (FRS) realtame estimation, also proposed here. Quite general estimation method, based on cross-terms-free time-frequency representations (TFDs), provides multiple detection of the local filter?s regions of support (in observed time-instant) in the practically only important case of a known single noisy signal realization. In this way, a very efficient real-time filtering of mono- and multicomponent nonstationary signals is enabled. Designed multicycle hardware design, required by the proposed estimation method, allows the implemented nonstationary Wiener filter to take different number of clock cycles per frequency point and to share functional kernels (that executes the TF representation) within the execution. In this way, (i) the application of the commonly used TFDs in the nonstationary filtering area, (ii) the optimization of the critical design performances (hardware complexity, energy consumption and cost) and (iii) the execution time improvement are provided.


    Paper Title, Authors, Abstract (Issue 2, Volume 2, 2008)


Inverse Wavelet Reconstruction for Resolving the Gibbs Phenomenon
Nataniel Greene

Abstract: The Gibbs phenomenon refers to the lack of uniform convergence which occurs in many orthogonal basis approximations to piecewise smooth functions. This lack of uniform convergence manifests itself in spurious oscillations near the points of discontinuity and a low order of convergence away from the discontinuities. Here we describe a numerical procedure for overcoming the Gibbs phenomenon called the inverse wavelet reconstruction method. The method takes the Fourier coefcients of an oscillatory partial sum and uses them to construct the wavelet coefficients of a non-oscillatory wavelet series.


FPGA-Based Real-Time Video-Object Segmentation with Optimization Schemes
M.M. Abutaleb, A. Hamdy, and E.M. Saad

Abstract: This paper presents the implementation of a segmentation process to extract the moving objects from image sequence taken from a static camera used for real time vision tasks. Various aspects of the underlying motion detection algorithm are explored and modifications are made with potential improvements of extraction results and hardware efficiency. The whole system is implemented on a single low cost FPGA chip, capable of real-time segmentation at a very high frame rate that reaches to 1130 fps. In addition, to achieve real-time performance with high resolution video streams, dedicated hardware architecture with streamlined data flow and memory access reduction schemes are developed. Data flow reduction of 38.6% is achieved by processing only one distribution at time through the hardware. Also, substantial memory bandwidth reduction of 60% is achieved by utilizing distribution similarities in succeeding neighboring pixels as well as word length reduction.


FPGA Implementation of a Telecommunications Trainer System
Dr. Rosula S.J. Reyes, Carlos M. Oppus, Jose Claro N. Monje, Noel S. Patron, Reynaldo C. Guerrero, Jovilyn Therese B. Fajardo

Abstract: Field programmable gate arrays (FPGAs) have been used in a wide range of applications including the field of telecommunications. This paper presents the use of FPGAs in the implementation of both analog and digital modulation that includes amplitude modulation, frequency modulation, phase modulation, pulse code modulation, pulse width modulation, pulse position modulation, pulse amplitude modulation, de ta modulation, amplitude shift keying, frequency shift keying, phase shift keying, time division multiplexing and different encoding techniques like non-return-to-zero line code, non-return-to-zero mark line code, nonreturn to zero inversion line code, Unipolar return-to-zero line code, bipolar return-to-zero line code, alternate mark inversion line code, and Manchester line code. Moreover, an FPGA can be designed to emulate a particular device like an oscilloscope, a function generator, or the like. This paper describes the capability of an FPGA to internally generate a low frequency input signal and through the use of a VGA port, it is able to display the signals in an output device. However, the use of FPGAs is not limited to the aforementioned applications because of its reconfigurability and reprogrammability.


New Methods and Algorithms for Analyzing Human Physiological Signals of Long-Termed Heartbeat Rates
Tansheng Li, Yoshitsugu Yasui, Qian Tian, Noriyoshi Yamauchi

Abstract: This research is about some new methods and algorithms for analyzing long-term heart beat rating data. To consider some characteristics of heart beat ratings, we compared several methods such as smoothing algorithm, wavelet-analysis with error elimination, application of low-pass filter and average method. All these methods and algorithms have their own advantages. Depending on different requirements, selection of different methods is available. When processing physiological signals, proper processing methods should be chosen.


An inversion/non-inversion dynamic optically reconfigurable gate array VLSI
Minoru Watanabe, Mao Nakajima, and Shinichi Kato

Abstract: Up to now, an optically differential reconfigurable gate array taking a differential reconfiguration strategy and a dynamic optically reconfigurable gate array taking a photodiode memory architecture have been proposed. The differential reconfiguration strategy provides a higher reconfiguration frequency, with no increase in laser power, than other optically reconfigurable gate arrays, however the differential reconfiguration strategy can not achieve a high-gate-count VLSI because of the area occupied by the static configuration memory. On the other hand, the photodiode memory architecture can achieve a high-gate-count VLSI, but its configuration is slower than that of the optically differential reconfigurable gate array using equivalent laser power. So, this paper presents a novel inversion/non-inversion dynamic optically reconfigurable gate array VLSI that combines both architectures. It thereby achieves both advantages of rapid configuration and a high gate count. The experiments undertaken in this study clarify the effectiveness of the inversion/non-inversion optical configuration method.


Maximal Invariant Sets of Multiple Valued Iterative Dynamics in Disturbed Control Systems
Byungik Kahng

Abstract: Invariant set theory is an important tool in the control theory. It has rich history that goes back over a century, yet it is still an active research topic both in pure mathematics and theoretical engineering. It is easy to reduce a traditional discrete-time control dynamical system to an iterative dynamics of one endomorphism in the phase space. It is not easy to do the same in the presence of the disturbance. The purpose of this paper is to show that we can overcome this difficulty using the dynamics of multiple valued maps. First, we show that the dynamics of disturbed control systems can be modeled by the multiple valued iterative dynamics. Second, we define and study the invariant sets, the maximal invariant sets, and the positively maximal invariant sets of the multiple valued iterative dynamical systems. Finally, as an application, we study the reachability problem of the maximal positively invariant sets of the multiple valued iterative dynamical systems.


Mobile Node Implementation for WSN Applications
Radu Dobrescu, Dan Popescu, Maximilian Nicolae

Abstract: The approach is front towards some directions: mobile sensor networks, wireless communications, localization and tracking, data acquisition. The work goals are the designing, the implementation, and the validation of a modular, adaptable system for identification, tracking, localization and data acquisition through sensors network whose nodes are situated on moving objects (platforms). Because of the mobility, transmission of data between the nodes is made through radio communications (wireless). Both concepts, the sensors network and the wireless communication, are parts of so called integrated systems (embedded systems). Measurements provided by sensors are uncertain, so they are capable to give parameter estimation only. The modular node can’t uphold on one sensor to supply enough information and, therefore, it must be used the fusion of data from several sensors in order to obtain more precise information. The paper presents a model of sensorial fusion, for identification and localization task, within a mobile node. The goal of the equipment, which is proposed for research and developed in an experimental version, is to associate, based on DSP architecture, modular procedures of signal processing (data acquisition, tracking, localization and communication). These procedures, which can be configure upon request, are meant to transmit numerical data through un-wired support, especially over wireless sensor networks (WSN). Each of the sensors groups, together with locally attached system for processing and communication from object in motion, becomes an intelligent node. The intelligent nodes communicate between them and with a priority node, named network management node. Two procedures for optimizing network topology and for tracking mobile nodes in this network, both ensuring minimum power consumption, are discussed. The solution for node safety displacement consists in two levels implementation: a low level section (the sensory level) and a high level section (the fusion data level). There are four main hardware modules incorporated in the intelligent mobile node structure: the communication module, the video module the data acquisition module, and the power module. Some detail on the mechanical, electrical and functional characteristics of this intelligent sensor network node and future possible applications are finally discussed. The simulations are made in virtual and real environment. The validation allowed the implementation of a prototype, able to be configured upon request, by the economic unit. Thus, the prototype was configured and experimented for two applications: a mobile robot network and a network of mobile objects for quality and safety of the environment.


Sky-Scanner: A New Paradigm for Air Traffic Management
M. Salerno, D. Rondinella, M. V. Crispino, G. Costantini, M. Carota, D. Casali

Abstract: Laser detection and tracking of aircrafts based systems (LIDARs, LIgth Detection And Ranging systems) are emerging as a critical design trend in development of new generation ATM (Air Traffic Management) paradigms, of which they are the main innovations. The realization of laser sensors as rotating laser range-finder arrays and their combination to versatile systems lead to major advantages for the application such as Air Traffic Control within Aerodrome Traffic Zone (ATZ), airport surveillance and ground to air laser communications, and last but not least to save cost usually at the same time with getting an improved ATC (Air Traffic Control) performance. These laser systems that today can be developed without particular difficulties are challenging classical ATM paradigms in many aspects. Nevertheless, it is commonly recognized that the effectiveness of these systems strictly relies on the capability to reliably perform a track data fusion with airport radars and to manage a new generation ATM paradigm. In particular, driving and control a data fusion between laser tracking data and radar tracking data a very high computation power is required.
The main goal of the presented project is therefore to develop a novel laser tracking technology (SKY-Scanner System) capable to detect and track of aircrafts up to at least 6 nautical miles from the ATZ barycenter, namely a facility of enabling techniques, protocols, numerical prediction tools and devices specifically designed for the analysis of the laser systems performances in ATC applications, with the final target of defining a new generation ATM paradigm based on radar and laser tracking data fusion, and ground to air laser communications. The proposed methodology is considered at the frontier of technological research but it represents the only realistic way to put solid basis for the fabrication of effective radar and lidar integrated systems for incorporation in new generation ATM paradigms.


About Theoretical and Practical Aspects of Current Mode RC Oscillators Design
Luiza Grigorescu, Ioana Diaconescu, Gheorghe Oproescu

Abstract: This paper addresses a group of constructive elements with which, (through adequate combinations) one can generate current mode RC oscillator transfer functions. Obviously this elements set is not unique. From the multitude of possible solutions only the solutions that accommodate the below conditions stand out:
-the active elements can be easily produced in monolithic technology,
-each oscillator must have two resistors or two capacitors connected to the mass.
The latter requirement is very important for the oscillators with variable frequency. It was made RC oscillators and its transfer functions, and it was made a study of errors which affects maintaining gain oscillations and frequency oscillation. The paper point out the experimental results obtain through RC oscillators implementation with PA 630 current conveyors showing that the current mode oscillators appears to be an interesting approach from the perspective of the simplicity/performance compromise.


The Proposed Genetic FPGA Implementation for Path Planning of Autonomous Mobile Robot
O. Hachour

Abstract: This paper proposes Genetic Algorithms (GAs) for path Autonomous Mobile Vehicle (AMV). This approach has an advantage of adaptivity such that the GA works perfectly even if an environment is unknown. First, we present a software implementation GA path planning in a terrain. The results gotten of the GA on randomly generated terrains are very satisfactory and promising . Second, we discuss extensions of the GA for solving both paths planning and trajectory planning using a Single Static Random Access Memory (SRAM) for Field Programmable Gate Array (FPGA). This new design methodology based upon a VHDL description of the path planning has the two (02) advantages : to present a real autonomous task for mobile robots, and being generic and flexible and can be changed at the user demand. The results gotten are promising.


    Paper Title, Authors, Abstract (Issue 3, Volume 2, 2008)


A Passive Power Factor Correction Technique for Single-Phase Thyristor-Based Controlled Rectifiers
R. Carbone

Abstract: An approach already introduced to correct in a very simple way the power factor (PF) of single-phase and three-phase diode rectifiers is extended to single-phase line-frequency phase-controlled rectifiers. Some recalls on the aforementioned PF correction technique and some fundamentals on the conventional controlled rectifier behaviour are stated in advance. Then, the conventional circuit of the single-phase thyristor-based rectifier is proposed to be modified in order to make possible the control of the DC-voltage mean value also in presence of a fully resistive behaviour of the DC-load, being this last condition an imperative constraint for the extension of the introduced passive power factor correction technique. Once modified the controlled rectifier circuit, the PF passive correction technique is theoretically extended to it and, then, it is practically operated on a circuit case-study, by using a lot of Pspice numerical simulations. For both uncontrolled and controlled rectifiers, the introduced PF passive correction technique is simply based on the use of a resistive-capacitive branch to be connected at the DC-terminals of the rectifier. By properly designing the parameter values of the correcting passive branch, the behaviour of the equivalent rectifier DC-load can be make fully resistive, so obtaining a rectifier AC-side absorbed current practically sinusoidal and in phase with the AC supplying voltage. The designing procedure of the introduced passive correcting branch is considered and investigated. Analyses of performances of the new controlled rectifier are developed with the help of several Pspice simulations on a DC-motor drive case-study of about 2.5 kW of active power and under different working conditions, obtained by varying the rectifier delay angle, ?, in order to control the speed and the power of the motor. Some perspectives on the possibility to improve the conversion efficiency of the modified rectifier, sensibly worsen because of the introduction of the dissipative elements (the resistor) on the proposed correcting branch, are also developed together with some final considerations on the practical meaning of the currently defined rectifier PF index, that does not seems able to properly evaluate and compare performances of different rectifiers.


Invariant Moments Applied to Fingerprint Recognition
Jorge Leon-Garcia, Gabriel Sanchez-Perez, Karina Toscano-Medina, Gualberto Aguilar-Torres, Hector Perez-Meana

Abstract: In this paper an automatic fingerprint recognition system based in fingerprint features and invariant moments is explained. A fingerprint is the visible impression that papillary produces when the papillary crest contact in a surface. The fingerprint is the oldest and the most popular characteristic used for recognition or verification of people. The fingerprint has unique features called minutiae, which are points where a curve track finishes (ending), intersect or branches off (Bifurcation). In this research the enhancement image is processed using two algorithms, the first one is Fast Fourier Transform (FFT) and the second one is a bank of Gabor filters. After the enhancement process an algorithm to minutiae information extraction is applied obtaining distance, angle and coordinates from the minutiae. The invariant moments are used to discriminate between those fingerprints that are confused.


Single-Precision Logarithmic Arithmetic Unit with Floating-Point Input/output Data
Lucian Jurca, Aurel Gontean, Florin Alexa, Daniel I. Curiac

Abstract: In this paper we offer an alternative for classical floating-point (FP) units to solve faster and with less area the multiplication or division of two single-precision operands. Also, these operations are performed faster and more accurately than in previous works that used logarithmic arithmetic. All computations are fused in order to perform one single non-redundant addition in the critical path for finding the logarithm of the result. A second non-redundant addition is used to produce the result in floating-point format. Using Matlab analysis, the conversion error was also diminished by using correction values in the content of look-up tables.


Design of Active Steering Controller of the Scaled Railway Vehicle
Min-Soo Kim, Yeun-Sub Byun, Hyun-Moo Hur

Abstract: Active steering system of railway vehicles has proven its ability to bridge the gap between stability and curve friendliness. This system consists of two steering actuators, a steering controller, and various sensor systems to detect lateral displacement, vibration, track curvature, and so on. Generally scaled railway vehicles were developed to reproduce the fundamental dynamic behavior of the full size railway vehicle in laboratory conditions. This paper describes the design of the active steering controller of a scaled railway vehicle to alleviate wheel/rail contact forces and to decrease wheel/rail wear. The control strategy is founded on motion of the wheel sets for lateral and yawing motions detected wheel/rail displacement. Running test results of 1/5 scaled active steering vehicle on the curved track show that the proposed active steering control system has good performance.


Wave Digital Approach - A Different Procedures for Modeling of Microstrip Step Discontinuities
Biljana P. Stosic, Miodrag V. Gmitrovic

Abstract: A theoretical model for the modeling of the microstrip structure as well as one type of regular discontinuity (step) is described. A microstrip structure, divided into cascade connection of uniform sections, can be efficiently modelled by wave digital networks. A wave digital network is a model of the microstrip structure modeled by wave digital elements. Appropriate choice of a minimal section number in that model is very important because of the direct influence on the sampling frequency of that digital model, and on accuracy of the desired response. Also, it is very important to achieve a good compensation of the effects of identified step discontinuities. In this paper, a choice of a minimal number of sections based on the given relative error and four different procedures for modeling the equivalent network of step discontinuity are presented. First of all, a wave digital element is formed for the equivalent T-network of the step discontinuity. In other procedures, the equivalent L-network of discontinuity is modeled by one equivalent transmission line, by cascade-connected two transmission lines, and by increasing the lengths of the lines in the junction. Verification of the results obtained is done in one example of bandpass filter.


The Design of High Frequency True Single Phase Clocking Divider-by-3 Circuit
Masayuki Ikebe, Yusuke Takada, Masaki Ohuchi, Junichi Motohisa, Eiichi Sano

Abstract: We evaluated the use of a true single phase clocking (TSPC) circuit as a high-frequency divider-by-3 circuit. This divider consists of two TSPC D-flip-flops (D-FFs) with NOR gate logic circuitry. To achieve high-speed operations as well as downsize the circuit, the NOR functions are implemented into the TSPC D-FF. We designed the divider using a 0.18-?m RF CMOS process; the circuit is 100 £ 200 ?m2. Compared with the existing design such as a source coupled logic circuit, a 50% reduction of circuit area was achieved. The power consumption and operating frequency of the proposed divider was investigated. In the measurements, we confirmed the frequency divided by 3 at less than 3.14 GHz clock with 2.34 mW. The circuit is implemented in low-power high-frequency dividers for wireless local area network applications.


    Paper Title, Authors, Abstract (Issue 4, Volume 2, 2008)


Mathematical Models and Numerical Simulations for Electro-Hydrostatic Servo-Actuators
Dinca Liviu, Corcau Jenica, Lungu Mihai, Tudosie Alexandru

Abstract: The electro-hydrostatic servo-actuators are expected to be the future of the actuations of the aircraft command surfaces. This paper presents some problems concerning these actuators and two mathematical models. There are shown also the results obtained by numerical simulation using the mathematical models of the servo-actuator. One mathematical model uses volume flow ratios to describe the servo-actuator functioning and the other mass flow ratio.


Speckle Noise Reduction and Edge-Enhancement of Coronary Plaque Tissue in Intravascular Ultrasound Image by Using Anisotropic Diffusion Filter
Takanori Koga, Eiji Uchino, Noriaki Suetake, Genta Hashimoto, Takafumi Hiro, Masunori Matsuzaki

Abstract: This paper describes a novel edge-preserved smoothing method with special consideration to an intravascular ultrasound (IVUS) image. An IVUS image, which is commonly used for a diagnosis of acute coronary syndromes (ACS), is very grainy due to heavy speckle noise. The speckle noise prevents not only the medical doctors’ interpretation of the IVUS image, but also the processing of medical images for computer-aided diagnoses (CADs). In order to reduce the speckle noise, in this study, we propose a modification of anisotropic diffusion filter in which a diffusion strength is locally and adaptively controlled by a weighted separability of an IVUS image. The weighted separability is a modification of separability for an edge detection with special consideration to an IVUS image. Furthermore, the proposed method not only reduces a speckle noise but also effectively enhances an edge of plaque tissue in an IVUS image. The effectiveness of the proposed method is verified by the experiments using the real IVUS images.


Algebraic Control of Integrating Processes with Dead Time by Two Feedback Controllers in the Ring RMS
Libor Pekar, Roman Prokop

Abstract: The objective of this contribution is to demonstrate the utilization of algebraic controller design in an unconventional ring while control integrating processes with time delay. In contrast to many other methods, the proposed approach is not based on the time delay approximation. A control structure combining a simple feedback loop and a two-degrees-of-freedom control structures is considered. This structure can be also conceived as a simple feedback loop with inner stabilizing loop. The control design is performed in the ring of retarded quasipolynomial (RQ) meromorphic functions (RMS) - an algebraic method based on the solution of the Bezout equation with the Youla-Kucera parameterization is presented. Final controllers may be of so-called anisochronic type and they ensure feedback loop stability, tracking of the step reference and load disturbance attenuation. Among many possible tuning methods, the dominant pole assignment method is adopted. This approach is compared with the conventional polynomial LQ method using an illustrative simulation example.


Speech Recognition using a Wavelet Transform to Establish Fuzzy Inference System through Subtractive Clustering and Neural Network (ANFIS)
A. M. Elwakdy, B. E. Elsehely, C. M. Eltokhy, D. A. Elhennawy

Abstract: In this paper, a proposed speech recognition algorithm is presented. This paper deals with the combination of a feature extraction by wavelet transform, subtractive clustering and adaptive neuro-fuzzy inference system (ANFIS). The feature extraction is used as input of the subtractive clustering to put the data in a group of clusters. Also it is used as an input of the neural network in ANFIS. The initial fuzzy inference system is trained by the neural network to obtain the least possible error between the desired output (target) and the fuzzy inference system (FIS) output to get the final FIS. The performance of the proposed speech recognition algorithm (SRA) using a wavelet transform and ANFIS is evaluated by different samples of speech signalsisolated words- with added background noise. The proposed speech recognition algorithm is tested using different isolated words obtaining a recognition ratio about 99%.


On–line Parametric Identification and Discrete Optimal Command of the Flying Objects' Move
Romulus Lungu, Mihai Lungu, Liviu Dinca, Eleonor Stoenescu

Abstract: This paper presents a new on-line parametric identification and discrete optimal command algorithm for mono or multivariable linear systems. The method may be applied with good results to the automatic command of the flying objects’ move. The simulation results obtained with this real time algorithm, with parametric identification for the longitudinal and lateral move of an aircraft are also presented. This algorithm may be used, with good results, for identification and optimal command of an air-air rocket’s move in vertical plain regarding to target’s line [1].


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