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ISSN: 1998-4464
All papers of the journal were peer
reviewed by two independent reviewers. Acceptance was
granted when both reviewers' recommendations were positive.
Main
Page
Paper
Title, Authors, Abstract (Issue 1, Volume 2, 2008) |
Pages |
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.
|
1-17 |
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.
|
18-25 |
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.
|
26-33 |
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.
|
34-41 |
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.
|
42-49 |
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.
|
50-55 |
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.
|
56-65 |
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.
|
66-72 |
Paper
Title, Authors, Abstract (Issue 2, Volume 2, 2008) |
Pages |
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.
|
73-77 |
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.
|
78-86 |
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.
|
87-94 |
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.
|
95-102 |
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.
|
103-112 |
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.
|
113-120 |
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.
|
121-130 |
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.
|
131-139 |
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.
|
140-150 |
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.
|
151-167 |
Paper
Title, Authors, Abstract (Issue 3, Volume 2, 2008) |
Pages |
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.
|
169-179 |
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.
|
180-188 |
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.
|
189-198 |
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.
|
199-208 |
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.
|
209-218 |
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.
|
219-228 |
Paper
Title, Authors, Abstract (Issue 4, Volume 2, 2008) |
Pages |
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.
|
229-238 |
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.
|
239-248 |
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.
|
249-263 |
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%.
|
264-273 |
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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274-283 |
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