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Issue 1, Volume 7,
January 2008
Title of the Paper: Performance
Analysis of Direct Digital Synthesizer Architecture with Amplitude Sequencing
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Authors: I.
Jivet, B. Dragoi
Abstract: The paper presents an analysis of a novel DDS architecture based on
direct amplitude algorithmic generation in its capacity to generate pure and
high frequency signals. The algorithm implementation requires very few
resources and is linear in digital precision length. In its simplest form
includes one compare, two additions and several increments per iteration
step. A solution to compensate the known major drawback of the algorithm,
sample phase non uniformity in time, is presented. The versatility of direct
digital synthesizers in frequency switching and phase modulation applications
is shown to be preserved in the new architecture. The paper also presents an
analysis of the potential of the proposed architecture performance as
reflected in the low harmonic spectrum of the quadrature output signals. A
FPGA implementation of the architecture was synthesized and simulated using a
VHDL description to validate the solution as proposed. Synthesis reports are
compared with other FPGA direct frequency synthesizer implementations as
reported in recent literature.
Keywords: Amplitude
centered DDS architecture, generated sine/cosine spectrum, FPGA
implementation
Title of the Paper: FPGA Implementation
of the Curve Generator Algorithm for H/W Acceleration Applications
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Authors: I.
Jivet, B. Dragoi
Abstract: The paper presents results of the implementation of a nonparametric
curve generator algorithm in FPGA as a test of concept for H/W acceleration
solutions. It is shown that coordinate sequences as a curve representation
when generated by the algorithm form a nonuniform sampled cosine/sine
sequences of values that can be used in signal generation applications. A
known draw back of the algorithm is the phase non uniformity of the samples.
The paper presents solutions to fix the non uniformity by sample time delay
compensation. A time sequence compensated extension of the algorithm is
presented for use in digital sine and cosine signal generation applications.
The VHDL description of the extended algorithm as proposed was simulated and
synthesized in a Xilinx family FPGA showing low gate count. Finally the paper
explores a second extension of the algorithm for random value trigonometric
function computation. The performance results are compared with recent known
coordinate transform solutions implemented in FPGA using the CORDIC algorithm
as reported in literature.
Keywords: H/W
acceleration, Jordan's
curve generator algorithm, FPGA implementation, CORDIC algorithm
Title of the Paper: Complex Chaotic
Dynamics of the Double-Bell Attractor
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Authors: M. S. Papadopoulou, I. M.
Kyprianidis, I. N. Stouboulos
Abstract: In this paper a novel non-autonomous 4th order chaotic oscillator
was investigated. This oscillator consists of a nonlinear resistance RN and a
negative conductance Gn. We have studied the dynamics of the circuit for
various values of the input sinusoidal signal vs(t) in the low frequency
area, both theoretically and experimentally. We have demonstrated the birth
and catastrophe of the Double-Bell strange attractor for different
frequencies values, as the amplitude Vo of the input signal varies. This work
is a precursor of future investigation of circuit’s application in secure communication
systems.
Keywords: Driven circuit,
Double-Bell attractor, Chaos, Spectrum analysis, Secure communication
Title of the Paper: Simulation Result
about Harmonics Filtering using Measurement of Some Electrical Items in
Electrical Installation on UHP EAF
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Authors: Manuela Panoiu, Caius Panoiu,
Mihaela Osaci, Ionel Muscalagiu
Abstract: This paper present the results obtained by simulation for the functioning
regime improvement of an UHP Electric Arc Furnace. Because the nonlinearity
of the electric arc the EAF functioning regime are perturbed from three
causes: the current harmonics, the reactive power and the unbalanced load. In
this paper there are study the possibilities of harmonics filtering and
compensate the reactive power. The study was made using the results of some
measurements made on an EAF and using an electric arc model for simulation.
The simulations are performed in PSCAD EMTDC simulation program, a program
dedicated to the power system.
Keywords: PSCAD-EMTDC
simulation program, electric arc modeling, harmonics mitigation, filtering,
reactive power compensation
Title of the Paper: About Stability of
Mechatronic Systems Driven by Asynchronous Motors
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Authors: Monica Adela Enache, Sorin
Enache, Mircea Dobriceanu
Abstract: This paper presents two methods for stability analysis of mechatronic
systems driven by asynchronous motors: an analytical method and a numerical
one, original, conceived by authors. The presentation is accompanied by
simulations and experimental results leading to credible conclusions.
Keywords: Stability, mechatronic system, asynchronous motor, parameters, simulation, Matlab,
experiment.
Title of the Paper: A System for Video
Conversion and Text Data Overlay
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Authors: Rafic Bachnak, Ramya
Chakinarapu, Mario Garcia, Dulal Kar
Abstract: This paper describes the design and development of a Video
Conversion and Data Overlay (VCDO) prototype that takes in an analog National
Television System Committee (NTSC) video signal generated by a video camera
and data acquired by a microcontroller and display them in realtime on a
digital panel. An 8051 microcontroller is used to acquire power dissipation
by the display panel, room temperature, and camera zoom level. The paper
describes the major hardware components and shows how they are interfaced
into a functional prototype. Test data results are presented and discussed.
Keywords: Overlaying Text
Over Video, Data Conversion, Real-Time Video
Issue 2, Volume 7,
February 2008
Title of the Paper: Algebraic
Derivation of the Oscillation Condition of High–Q Quartz Crystal Oscillators
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Authors: Nicolas Ratier, Remi Brendel
Abstract: A symbolic–numeric method to simulate a high–Q quartz crystal
oscillator is derived in this paper. The proposed method can take into
account the isochronism defect of the resonator when high precision
simulations are needed. The oscillator circuit is expressed under a canonical
5–terminal network which can be easily handled. The oscillator behavior is
then described under the form of a nonlinear characteristic polynomial whose
coefficients are functions of the circuit components and of the oscillation
amplitude. The steady state oscillation amplitude and frequency are
determined by solving the polynomial in the frequency domain. Moreover, if
tolerance is assigned to each circuit component, efficient worst case
analysis can be performed.
Keywords: Quartz Crystal
Oscillator, Nonlinear, Simulation, Characteristic Polynomial, n–Terminal
Network
Title of the Paper: Research and
Implementation of A Novel DC High Voltage Power Supply
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Authors: Zhao Yanlei
Abstract: The high voltage power supply is widely used in various fields. The
paper presents detailedly the topology, the operation and the key techniques of
a high precise direct current (DC) negative high voltage power supply. To
enhance the power factor of input side and the voltage precision of output
side, the power supply uses BOOST converter for power factor correction and
voltage regulation. It converts DC to high frequency (HF) alternating current
(AC) square wave with phase-shifted full bridge. The voltage of the AC square
wave is boosted by HF transformer, then the HF high voltage AC square wave is
double rectified to DC high voltage output. The HF high voltage transformer,
which is designed and manufactured with special material—polytetrafluoro
ethylene (F4) and special technique, solves several technical difficulties
including influence of distributing parameters and insulation, and meets
demands of high frequency, high voltage and high power. The supply’s output
voltage is 25kV and its maximal output current is 100mA.The experimental
result shows the power supply has high input power factor, stable output
voltage and small ripple.
Keywords: Power supply
high voltage Boost Transformer ZVS phase-shifted control
Title of the Paper: Ultrashort Pulse
Measurement using High Sensitivity two Photon Absorption Waveguide
Semiconductor
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Authors: Mohammad Mehdi Karkhanehchi
Abstract: Two photon absorption in a reverse-biased pin AlGaAs optical
waveguide is observed. This waveguide was used as a combined nonlinear mixer
and detector of an autocorrelator for measuring the pulse width of 1.3μm
wavelength optical pulses. The autocorrelation trace gives the FWHM of a
1.3μm Q-switched semiconductor laser to be approximately 13 ps.
Keywords: Two photon
absorption, autocorrelator, semiconductor laser, Q-switching, optical
waveguide
Title of the Paper: Mathematical Models
of High-Speed Trains Movement
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Authors: Cismaru Cristian Daniel,
Nicola Doru Adrian, Manolea Gheorghe, Drighiciu Mircea Adrian, Bulucea
Cornelia Aida
Abstract: In the paper it is presented the mathematical model of the useful
movement of the high-speed trains. On the mathematical model basis it is
built the structural diagram associated of the useful movement. The obtained
structural scheme can be easily implemented in SIMULINK. An immediately
example of the utilization of the useful movement model it constitutes the
drawing of the movement diagrams, which it illustrates the dynamics aspect of
the useful movement. Like application, by means of the SIMULINK model they
are traced, on the basis of the traction and braking characteristics and of
the imposed conditions of the route, the movement diagram of the high-speed
train.
Keywords: modeling,
simulation, electric vehicle, high-speed train, useful movement
Title of the Paper: Design and
Implementation of Self-Calibration for Digital Predistortion of Power
Amplifiers
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Authors: Dua Idris, Yannick Le Moullec,
Patrick Eggers
Abstract: The linearization of Power Amplifiers (PAs) on mobile handsets is a
critical problem for stringent systems such as WiMAX. In this paper we
present the results of our investigation on the feasibility of
self-calibration from a theoretical point of view as well as on a FPGA-based
hardware platform for the predistortion of PAs. We propose a system design in
three phases i) self-calibration, ii) inverse function calculation and iii)
predistortion. MATLAB simulation results show that the functionality of the
self-calibration, inverse function calculation and predistortion can
linearize the PA characteristics and that the FPGA implementation results of
the self-calibration are promising, paving the way for an efficient
self-calibrating digital predistorter.
Keywords: DPD,
self-calibration, PA
Title of the Paper: Nonuniform Sampling
Delta Modulation - Decoding Problems
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Authors: Ryszard Golanski, Jacek
Kolodziej
Abstract: The problems of reconstructing signals coded with use of adaptive
sampling delta modulation have been shown in the paper. Synchronization
procedure of the algorithm "with return to the basic sampling
instant" has been analyzed. Investigations of the bit error robustness
of the delta system with sampling adaptation have been presented. Special
interest was aimed at the behaviour of Non-uniform Sampling Delta Modulation
system with reference to the transmission errors. The phenomena of the
parasitic oscillation and dynamic regulation of the dc level in the
reconstructed signal, as a result of the channel errors, have been discussed.
Parasitic oscillation parameters have been analyzed. It has been found that
the algorithm "with return to the basic sampling instant" improves
the bit error robustness of the adaptive sampling delta modulation.
Keywords: Adaptive delta
modulation, Non-uniform sampling, Error compensation, Robustness, Parasitic
oscillation.
Issue 3, Volume 7,
March 2008
Title of the Paper: On Bifunctional
Polymorphic Gates Controlled by a Special Signal
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Authors: Richard Ruzicka
Abstract: Polymorphic digital circuits are circuits composed of polymorphic
(multifunctional) as well as ordinary gates. In addition to its standard
logic function (such as NAND), a polymorphic gate exhibits another logic
function which is activated under a specific condition, for example, when
Vdd, temperature, illumination or a special signal reaches a certain level.
This paper describes existing polymorphic gates and their features, benefits
and limits and discusses special class of polymorphic gates – bifunctional
polymorphic gates controlled by a special signal. These gates seem to be most
flexible polymorphic gates. In the paper a new two-input bifunctional gate
for polymorphic circuits is proposed. The gate produces NAND or XOR function
according to a special signal. The proposed gate is effective in terms of
area overhead – it consists of 9 transistors only, while corresponding
circuit employing conventional gates consists of more than 10 transistors.
Keywords: hardware
engineering, digital circuits, CMOS logic gates, polymorphic electronics,
VLSI, reconfigurable digital circuits
Title of the Paper: A Low Cost
CPLD-Based Ultrasonic Flowmeter
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Authors: Ioan Lie,
Virgil Tiponut, Ivan Bogdanov, Sabin Ionel, Catalin Daniel Caleanu
Abstract: Based on the characteristics of ultrasonic non-contact measurement
and the combination of temperature measurement with ultrasonic flow
measurement, a flowmeter was designed. The structure of the ultrasonic
flowmeter and the circuits of temperature and flow measurement were
described. The design method of the meter with low power consumption was
given by selecting MSP430 single chip microcomputer. In order to enhance
flowmeter's precision and stability a Xilinx CoolRunner CPLD was applied in
high precision timing. The result is a low cost portable solution working
with a 3.3V supply and operating with ultrasonic transducers at 1MHz
frequency.
Keywords: ultrasonic
flowmeter, delay line, transit-time, CPLD, ultrasonic transducer
Title of the Paper: Dedicated hardware
for Inheritance-Oriented Crossover Operation
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Authors: Masaya Yoshikawa, Kentaro
Otsuka, Hidekazu Terai
Abstract: Traveling salesman problem is basic combinatorial optimization problem
of various practical applications in engineering. Genetic Algorithm (GA) is
one of algorithms to solve the traveling salesman problem efficiently. GA is
a powerful optimization algorithm, which is based on the mechanism of
biological evolution. However, an essential difficulty exits in GA with
regard to large amount of computation time, because GA is population-based
search algorithm. Reducing the computational time is the most important
priority, if GA is applied to practical problems. On the other hand, GA has
three genetic operations, and the crossover operation is one of the most
important genetic operations. In this paper, we propose novel hardware
architecture for crossover operation in order to reduce computation time
while keeping the search performance. The proposed architecture introduces a
new hardware-oriented crossover algorithm considering character inheritance.
Experiments prove that the proposed architecture achieves not only high speed
processing but also reduction of the number of processing steps, while
keeping the quality of solution.
Keywords: Hardware
architecture, Crossover engine, Traveling Salesman Problem, Character
inheritance, Genetic Algorithm, High speed processing
Title of the Paper: Dynamic Stability
Analysis based on Energy-Passivity Considerations
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Authors: Chieh-Tsung Chi
Abstract: This study aims at researching the relations between the stability
characteristics of an ac contactor and the passivity conditions during power
disturbances such as voltage sag. Based on the basic definitions of energy
passivity, the stability performance of contactor can be determined by
employing the flux linkage versus coil current curve of contactor. On the
basis of the governing equations of ac contactor, a digital simulation model
is first established. The correctness of the contactor model is verified by
comparing the difference of the coil current and the armature displacement
between model and contactor. The dynamic stability of contactor can be
determined by the energy transferred direction in the electric part or the
polarity of the time rate of the change of coil inductance. There are three
types of voltage sag are respectively assumed to be the experimental case.
Finally, we found that the results which were obtained from simulation tests
agree well with those of the theoretical inferences. The identifying rules of
the stability of contactor during voltage sag are presented here is valuable
for the contactor designer to draft an effective compensation strategy in
future so as to improve the momentary performance of contactor.
Keywords: Dynamic
stability, contactor, passivity, energy, voltage sag, model
Title of the Paper: Current Or/And
Voltage-Mode Quadrature Oscillators with Grounded Capacitors and Resistors
using FDCCIIs
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Authors: Jiun-Wei Horng,
Chun-Li Hou, Chun-Ming Chang, Shih-Ting Cheng, Hsin-Yu Su
Abstract: Two quadrature oscillator circuits each using one fully
differential second-generation current conveyor (FDCCII), two grounded
capacitors and two grounded resistors are presented. The current-mode
quadrature signals can be obtained from the first proposed circuit. The
current-mode and voltage-mode quadrature signals can be simultaneously
obtained from the second proposed circuit. In both proposed circuits, the
current-mode quadrature signals have the advantage of high output impedance.
The oscillation conditions and oscillation frequencies are orthogonal
controllable. The use of only grounded capacitors and resistors makes the
proposed circuits ideal for integrated circuit implementation. Simulation
results are included.
Keywords: Quadrature
oscillator, Current-mode, Voltage-mode, Current conveyor, FDCCII.
Title of the Paper: Efficient
Implementation and Performance Evaluation of the Second Order Volterra Filter
based on the MMD Approximation
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Authors: Georgeta Budura, Corina Botoca
Abstract: Considered as a prototype of nonlinear system models the second
order Volterra filter (FV2) is characterized by an increased complexity in
comparison with a linear filter. This complexity is given by the large number
of filter coefficients, as well as by the filter operations and it requires
an increased computational power in technical applications. The filter based
on the multi memory decomposition (MMD) structure represents a good
approximation of the FV2 and significantly reduces the number of filter
operations. In this paper we propose an efficient implementation of the MMD
filter studied in a typical nonlinear identification problem. The simulations
show the very good performance of our proposed MMD structure in comparison
with the results obtained by using a second order LMS Volterra filter. We
have evaluated the performance of our method based on the system response to
different input signals.
Keywords: second order
Volterra filter, multi memory decomposition, efficient implementation,
performance evaluation
Title of the Paper: Reactive Power
Requirements of Grid Connected Induction Generator in a Weak Grid
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Authors: K. S. Sandhu, Shelly Vadhera
Abstract: Induction generators are gaining the popularity due to its
simplicity and no synchronization problem. However the major drawback of this
machine is its additional reactive burden on the system, where it is
connected. In this paper an attempt is made to explore the performance of a
grid connected induction generator (GCIG) due to weak grid conditions i.e.
voltage and frequency fluctuations. Iterative model developed by the authors
is used to predict the reactive burden of the generator due to voltage and
frequency fluctuations. The comparison between experimental and simulated
results proves the validity of technique proposed. Further proposed modeling
is also used to include the effects of saturation.
Keywords: Grid connected
induction generator, Iterative technique, Magnetizing reactance, Saturation,
Weak grid
Issue 4, Volume 7,
April 2008
Title of the Paper: Current-Starved
Pseudo-Floating Gate Amplifier
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Authors: Mehdi Azadmehr, Yngvar Berg
Abstract: In this paper we present Current-Starved Pseudo-Floating Gate
(CSPFG) inverters with capacitive feedback. The analog CSPFG inverter
suppresses low frequencies due to the active, local feedback. This inverter
can be used in designing circuits and amplifiers where high frequency signal
processing is the main goal. One good area of use is in filter design where a
narrow band pass or reject filter is to be designed. Typical applications are
detection of high frequency components in sensor signals, i.e. airbag
sensors. AC simulation of the inverter is presented to show that the circuit
is suited for high performance filter design. Linearity simulations of the
analog CSPFG inverters shows the good transient properties suited for
amplifier design.
Keywords: Analog, CMOS,
Floating gate, Inverter, Amplifier, Filter.
Title of the Paper: Real-time Voltage
Control to Improve Automation and Quality in Power Distribution
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Authors: Francesco Muzi
Abstract: A new power digital voltage controller is described able to improve
quality in power distribution using real-time compensation of both slow
voltage changes and quick disturbances as sags and swells. Voltage control
was achieved by means of a special transformer able to change the magnetic
flux linked to the secondary winding; moreover, secondary voltage was
monitored through a feedback control managed by a properly programmed
micro-controller. The completely automated system includes a power section,
namely a special transformer, a power electronic section consisting of an
inverter driven by an actuator, and a digital section involving a
micro-controller with implemented software. The capabilities of the proposed
voltage conditioner were verified by laboratory experimental tests performed
on a specifically manufactured prototype. Experimental results are reported
and the behavior of the conditioner under different working conditions is
discussed.
Keywords: Electrical
distribution systems, Power quality, Power systems control and automation,
Voltage conditioning.
Title of the Paper: Reliability
Assessment and Improvement of Large Power Induction Motor Winding Insulation
Protection System using Predictive Analysis
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Authors: Mahfoud Chafai, Larbi Refoufi
, Hamid Bentarzi
Abstract: The paper presents a reliability assessment of a widely used
protection system of large power squirrel cage induction motors. In conjunction
with published field induction motors Failure data this assessment effort is
based on a integrated predictive analysis using three methods: (1) a Fault
Tree Analysis (FTA) that allows to identify and then quantify the initiating
failure cause weighting factors; (2) an Event Tree Analysis (ETA) that allows
to predict the protection system probability outcomes following an external
disturbance and (3) a Failure Mode Effect and Criticality Analysis (FMECA)
that will help set the stage for developing a preventive maintenance program
fit to keep up the induction motor protection system reliability at the
required level with particular attention given to aggressive environmental
factors such as found in cement plants.
Keywords: FTA, ETA,
FMECA, Induction motors , Protection, Reliability , Failure Modes.
Title of the Paper: PWM Encoding Method
for Wireless Communication in Sensor Networks
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Authors: Ciprian
Seiculescu, Ioan Lie, Aurel Gontean
Abstract: When designing low power sensor with radio capabilities the choice
of the encoding for the radio signal can have great impact on performance and
implementation requirements. The paper presents different encodings with
their advantages and disadvantages, looking at both performance and
implementation requirements. Finally the paper presents a proposed PWM
encoding and the way that it was implemented and shows that the
implementation advantages over other more traditional encoding outweigh the
loss in performance. As well the paper presents different implementation
methods for transmitters and receivers using the PWM encoding.
Keywords: PWM, amplitude
modulation, Low power sensors networks, FPGA Prototyping, radio communication
Title of the Paper: Design and
Implementation of DC Motor Speed Controller using Fuzzy-Adaptive Controllers
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Authors: Hengameh Kojooyan Jafari
Abstract: As adaptive control systems have parametric construction and high
accuracy against disturbances, and fuzzy control systems can compensate
deficiency of dynamic parameters in time [1], in this paper fuzzy–adaptive
controllers is used. Drive method is PWM and 8955 microcontroller is used for
DC motor speed controlling. Simulation studies has been performed by MATLAB
SIMULINK6.1 and SIDE51 (ver1.04R11) software by C language is used for
program of controller and its compiler is used for making hex file to program
8955 microcontroller by EPROM PROGRAMMER (PGM89)[6,7] . The DC motor is
VGFMED-BSMIB52 and driving IC is L298 IC.
Keywords: Fuzzy-adaptive
control, Microcontroller, DC motor .
Title of the Paper: Optimization
Frequency Design of Eddy Current Testing
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Authors: Narong Mungkung, Komkrit
Chomsuwan, Narong Pimpru, Toshifumi Yuji
Abstract: The purposes of this research were to construct the nondestructive
metal testing instrument by using eddy current method and to find an optimal
frequency for the metal testing instrument. The testing instrument consist of a
sine wave oscillator circuit which can adjust the frequency between 20 – 90
kHz, and a 50 ohms sensor circuit. There are three kinds of testing
instrument. The first was the nondestructive imperfection testing by using
eddy current method. The sample irons are constructed with different
imperfection on surface. The output signals of testing from the sensor
circuit are compared. The second was the nondestructive categorization metal
testing by using eddy current method. Many kinds of metals are taken to
testing. The last one was the nondestructive testing for finding the
thickness of films on iron by using eddy current method. In this testing the
thickness of films varied between 100 – 700 microns. In all testing,
differences of the signal testing were compared to analyze the optimal frequency
for the testing instrument. The results of research showed that the
nondestructive metal testing instrument by using eddy current method can be
used to find a different imperfective iron, categorize the metal and find
thickness of films. In addition, the range of an optimal frequency is 30 kHz
to 70 kHz for testing instrument.
Keywords: Nondestructive
, eddy current, thickness of films, optimal frequency
Title of the Paper: Behavioural
Modelling of On-Chip Optical Interconnect with Potential Applications for
Testing Linking-with-Light Circuits and Systems
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Authors: HJ Kadim
Abstract: An integrated circuit (IC) or a system where light beams displace wires
or metallic interconnects to pass signals between different subsystems
requires new test techniques. Based on a knowledge of light properties and
the transmitting medium, possible factors or parameters that may affect the
propagation of light and the consequent changes in the expected output can be
identified. Using these parameters as the ingredients, a mathematical model
is constructed to study the effect of parameter fluctuations on the on-chip
optical interconnect and hence providing information that will assist in
identifying abnormal deviations in circuit’s behaviour.
Keywords: Optical
interconnect, test, modelling, parameter fluctuations, SoC
Title of the Paper: Capacitive Sensing
Device in a Postural Control System
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Authors: Ivan Marinovic,
Duje Coko, Igor Zanchi
Abstract: This paper presents a theremin used as a sensing device which provides
a DC voltage output proportional to distance between the device and a human
body in standing position. This device consists of a pair of
Butler’s oscillators, a heterodyning mixer,
a low-pass 4th order Butterworth filter and a frequency-to-voltage converter.
Output signal may be sent to another device such as an actuator or a
measurement module, depending on the application type. Three sets of
measurements for various types of sensing electrodes have been taken, and a
third degree polynomial function has been fitted using a least square method.
Keywords: Human posture
identification, proximity sensing, theremin, Butler’s oscillator, posturography, least
square method, curve fitting
Title of the Paper: On-Line Dynamic
Cable Rating for Underground Cables based on DTS and FEM
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Authors: Y. C. Liang, Y. M. Li
Abstract: The development of surface temperature on-line monitoring
techniques for 110kV and above XLPE power cable gives a strong support to
power cable load dynamic adjustment. However, the problem is how to determine
the conductor temperature from the surface temperature. A technique based on
distributed temperature sensing (DTS) and finite element method (FEM) is
presented to estimate the soil thermal properties by matching the computed
thermal fields to that obtained from measurement and predict the realtime
current carrying capacity by iterative method in order to prevent overheat of
insulation. Compare with the thermal circuit model, the method based on DTS
and FEM is more accuracy.
Keywords: Online
monitoring, Dynamic cable rating, Distributed temperature sensing, Finite element method, current
carrying capacity, Underground cables
Title of the Paper: A Numerical
Evaluation of Damages Caused by Asynchronous Motors to the Environment
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Authors: Francesco Muzi, Luigi
Passacantando
Abstract: In recent years a slow but progressive increase in the world’s
temperatures has been consistently recorded. To oppose this global warming
trend, two especially important actions are the monitoring and reduction of
greenhouse emissions, in large quantity caused by global electric energy
production. To this regard an algorithm is proposed to estimate the particles
released into the atmosphere as a consequence of the electric energy produced
for the operation of asynchronous motors, which in industrialized countries
absorb as much as 60 % of the total electric energy generated. The described
procedure can also help to evaluate the possibility to supply motors with
electric energy produced from renewable sources instead of from thermal power
plants supplying traditional public networks, which would of course reduce
the environmental impact of motors to almost zero. Emissions linked to
electric energy generation were evaluated on the basis of statistics
collected from the main electric utilities. The proposed algorithm was validated
by means of laboratory tests performed on a single asynchronous motor working
under different operating conditions.
Keywords: Electric motor
operation and consumption, Emissions and pollution, Environmental
sustainability.
Title of the Paper: Device and Memory
Array Models for Flash EEPROM Technology
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Authors: Hassen Aziza, Bertrand Delsuc
Abstract: In this paper, three EEPROM memory cell models are presented. The
first model is a compact model based on Mos Model 11 (MM11) and fully
validated on silicon. From this first model we propose two alternative models
(level 1 & level 2). These last models allow a reduction of simulation
time and memory space overheads, with respect of accuracy, compared to the
original compact model. The technique used to build the level 1 and level 2
models is based on the complexity reduction of the original EEPROM model. We
also present simulation time results using the different models within memory
arrays.
Keywords: EEPROM,
Modeling, Memory arrays, Simulation time.
Title of the Paper: Use of RBF Neural
Network in EMG Signal Noise Removal
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Authors: V. R. Mankar, A. A.
Ghatol
Abstract: The bioelectric potentials associated with muscle activity constitute
the electromyogram (EMG). EMG signal is used in biomedical applications to
detect abnormal muscle electrical activity that occur in many diseases and
conditions like muscular dystrophy, inflammation of muscles, pinched nerves,
peripheral nerve damages, amyotrophic lateral sclerosis, disc herniation,
myasthenia gravis and others. In this paper, it is depicted that an RBF
neural network as compared with other types of neural networks can be
effectively used for EMG signal noise removal, which is a typical nonlinear
multivariable regression problem. The performance parameters i.e. MSE and
correlation coefficient are found to be in the expected range of values.
Keywords: EMG, RBF, MSE, MLP, PE,
Correlation Coefficient, NN.
Title of the Paper: User Intention
based Personalized Search : HPS (Hierarchical Phrase Search)
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Authors:
GunWoo Park,
JinGi Chae, Dae Hee Lee, SangHoon Lee
Abstract: Personalized search has recently got significant attention in the
web search. Accordingly, user’s intention of search is very important
information to retrieval information in aspect of personalized Search.
Although many personalized search and strategies have been proposed, the
majority of web users are difficulty in retrieval information corresponding
their search intention. In this paper, we present personalized search based
on User Intention through the HPVM(Hierarchical Phrase Vector Model) to solve
these problems using and machine learning methodology. Users can navigate
through the prior user’s intention by their own needs. This is especially
useful for various meaning and poor queries. By analyzing the results, we
find out that there is an unique representation of user intention under
different queries, contexts and users. Furthermore, we can find out that this
knowledge is very important in improving personalized information retrieval
performance by filtering the results, recommending a new query, and distinguishing
user’s characteristics. With this approach, search engines can provide more
predictive information for Web searchers. Based on this approach, we
developed a personalized search engine, HPS (Hierarchical Phrase Search).
Keywords:
Personalization, Information retrieval, Hierarchical phrase search, Support
vector machine, Machine learning, Relevance feedback
Title of the Paper: An Efficient Error
Resilience Scheme based on Wyner-Ziv Coding for Region-of-Interest Protection
of Wavelet based Video Transmission
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Authors: Zhuo Xue, K. K. Loo, J. Cosmas, P. Y. Yip
Abstract: In this paper, we propose a bandwidth efficient error resilience
scheme for wavelet based video transmission over wireless channel by
introducing an additional Wyner-Ziv (WZ) stream to protect region of interest
(ROI) in a frame. In the proposed architecture, the main video stream is
compressed by a generic wavelet domain coding structure and passed through
the error prone channel without any protection. Meanwhile, the predefined ROI
area related wavelet coefficients obtained after an integer wavelet transform
will be specially protected by WZ codec in an additional channel during
transmission. At the decoder side, the error-prone ROI related wavelet
coefficients will be used as side information to help decoding the WZ stream.
Different size of WZ bit streams can be applied in order to meet different
bandwidth condition and different requirement of end users. The simulation
results clearly revealed that the proposed scheme has distinct advantages in
saving bandwidth comparing with fully applied FEC algorithm to whole video
stream and in the meantime offer the robust transmission over error prone
channel for certain video applications.
Keywords: Distributed
Video Coding, Wyner-Ziv, Wavelet, ROI, Integer Wavelet Transform.
Title of the Paper: Benchmarking in
Digital Circuit Design Automation
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Authors: Lech
Jozwiak, Dominik Gawlowski, Aleksander Slusarczyk
Abstract: This paper focuses on benchmarking, which is the main experimental
approach to the design method and EDA-tool analysis, characterization and
evaluation. We discuss the importance and difficulties of benchmarking, as
well as the recent research effort related to it. To resolve several serious
problems related to quality of benchmarking and use of practical industrial
benchmarks, we proposed an adequate benchmarking methodology based on the
statistical experimental design approach, and developed corresponding digital
circuit benchmark generators. These benchmark generators enable research,
evaluation and fine-tuning of circuit synthesis methods and EDA-tools largely
independent of the actual industrial benchmarks, and much better than having
only some industrial benchmarks. Using the results of extensive experiments
that involved large sets of diverse benchmarks generated with our FSM benchmark
generator, we discuss several crucial problems of benchmarking and
demonstrate how to resolve them.
Keywords: Microelectronic
Circuit Design, Digital Circuits, EDA-tools, Benchmarking, Statistical
Experimental Design, Benchmark Set Quality
Issue 5, Volume 7,
May 2008
Title of the Paper: A General
Mathematical Model Based on Laplace and
Modified Z-Transform for Time and Frequency Domain Investigation of
Three-Phase Switched Circuits
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Authors: Jiri Klima
Abstract: A general mathematical method for both the time-domain and
frequency domain analysis of power converters with periodic switching
cuircuits is proposed .The method is based on mixed using of the Laulace and
modified Z-Transform in linear periodically time-varying system. The model
was used for the analysis of three-phase voltage source inverters with Space
Vector PWM feeding a three-phase static load, or an induction motor drive but
it is applicable for all types of converters with an explicitly determined
output voltage (converters with forced commutation) and periodical
modulation..From the modulated waveforms we can easily obtained equations for
the six step waveforms.The derived equations are validated using a 3 kW
three-phase inverter.
Keywords: Mathematical
model,Laplace transform,Modified Z-Transform
Title of the Paper: Pulse Density
Recurrent Neural Network Systems with Learning Capability using FPGA
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Authors: Yutaka Maeda, Yoshinori Fukuda, Takashi Matsuoka
Abstract: In this paper, we present FPGA recurrent neural network systems
with learning capability using the simultaneous perturbation learning rule.
In the neural network systems, outputs and internal values are represented by
pulse train. That is, analog recurrent neural networks with pulse frequency
representation are considered. The pulse density representation and the
simultaneous perturbation enable the systems with learning capability to
easily implement as a hardware system. As typical examples of the recurrent
neural networks, Hopfield neural network and the bidirectional associative
memory are considered. Details of the systems and the circuit design are
described. Analog and digital examples for these Hopfield neural network and
the bidirectional associative memory are also shown to confirm a viability of
the system configuration and the learning capability.
Keywords: Hardware
implementation, Pulse density, Hopfield neural network, Bidirectional
associative memory, Learning, Simultaneous perturbation, FPGA
Title of the Paper: Lump Circuits
Elements Values Extraction of Acoustic Transducers using Impedance
Measurement Approach
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Authors: Yeong-Chin
Chen, Lon-Chen Hung, Shuh-Han Chao, Tseng-Hsu Chien
Abstract: Acoustic transducers are the popular elements for sonar array. The
transducer of the simplify electrical equivalent circuit is discussed, and a
impedance measurement system is developed to estimate the elements value of
transducer’s lump circuit model at or near resonance. For practial
application, a matching transformer is designed to make the transducer a high
efficiency and high power transmitter. The experiment result approves the.
Impedance Measurement Approach is the effective method for high power
acoustic transducer development.
Keywords: Lump circuits,
Elements values extraction, Acoustic transducers, Impedance measurement
Title of the Paper: Improvements in
Power Quality and Efficiency with a new AC/DC High Current Converter
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Authors: Francesco Muzi, Luigi Passacantando
Abstract: A very flexible AC/DC converter featuring high-output current,
reduced voltage ripple and highly adjustable current control is described.
The whole system consists of four stages and uses a proper switching
technique in conjunction with a feedback control performed by means of a PID
regulator. Moreover, the built prototype exhibits high efficiency and reduced
harmonic pollution. In order to evaluate the harmonic distortion on the
current drawn from the supply network, an FFT (Fast Fourier Transform)
analysis is performed. Finally, experimental and computation results for
output currents up to 400A, which confirm the correct behavior of the
proposed converter, are presented and discussed.
Keywords: AC/DC
converter, High direct-current, FFT, Electrical distribution systems, Power
quality.
Title of the Paper: Design and
Calculation Method for Dynamic Increasing Transmission Line Capacity
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Authors: Lijia Ren, Xiuchen Jiang,
Gehao Sheng, Wu Bo
Abstract: The Dynamic Line Rating (DLR) system is designed to improve the
transmission capacity of overhead lines, which decreases or delays to
re-build transmission lines. The system is composed of sampling terminals
installed on dead-end configuration of a line and one control instrument
equipped in dispatch center. The data between the sampling terminals and the
control instrument is transmitted through GPRS/GSM. Through Ethernet, the
control instrument exchanges data with SCADA interface in order to integrate
DLR and SCADA system. A solar Photovoltaic (PV) power supply system based on
Perturb & Observe MPPT techniques was designed and successfully applied
to outdoor on-line monitoring DLR system. The paper analyzed mechanical
actions for overhead line concerned wind speeds and wind direction in a
deflection plane. The force balance for overhead line in wind was analyzed in
detail, which deduces the mechanical model to calculate sags from the
measured tension. Overhead line’s state equation was corrected used the
relation of temperature and sags, and deduced the ultimately line’s
temperature. Analyzed the advantages and drawbacks of some mathematical model
used to calculate transmission capacity. In order that the DLR system
received the optimum dynamic capacity curve, combined the WM and TS model.
The result shows that the DLR system is effective in increasing line capacity
without violating the legal ground clearance, monitoring the on-line
parameters of transmission lines, and insuring the safe ground clearances of
transmission line at all times.
Keywords: Dynamic Line
Rating (DLR); Transmission line; Transmission capacity; Data acquisition
terminal; Photovoltaic Power Supply, MPPT, Conductor sag; Conductor tension
Title of the Paper: Accident Analysis of
a Surveillance Camera System through a Frequency-Based Processing
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Authors: Jaejoon Kim, Dae Gyu Lee
Abstract: The surveillance camera systems are commonly used in detecting the
traffic violation on the roads. A key requirement in most detection systems
is the ability for rapid automated analysis to identify the accidents. This
paper describes an accident analysis based on frequency information for
detecting the accident, identifying the cause of the accident and storing the
accident scene. When an accident happens, the surveillance system analyzes
the accident sound and stores the accident scene in real-time. The proposed
system utilizes the sound magnitude (dB) and frequency analysis (FFT) in
order to increase the accuracy of accident assessments. In addition, this
system accomplishes a continuous buffering without the presence of an
accident. It stores the prior accident scene, accident scene and post
accident scene. When this system is applied to the actual crossroads, it can
detect the accident presence and save the inspection expense. Results of
applying the proposed technique to data obtained from the detection of
accidents are presented and compared.
Keywords: Traffic
accident surveillance system, accident scene, sound analysis, frequency
information, accident presence, accident inspection.
Title of the Paper: Embedded Real-Time
Video Encryption Module on UAV Surveillance Systems
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Authors: Ciprian Racuciu, Nicolae Jula,
Constantin Balan, Cosmin Adomnicai
Abstract: A real-time video encryption module, developed to be used on an
electrical accelerated mini-helicopter (UAV), is presented in this paper. The
surveillance system is composed from six modules: image capture, encryption,
two radio link modules, decryption and display module. The hart of the
encryption system is the CV700C motherboard and it’s VIA C7 microprocessor
with ultra low power consumption and efficient heat dissipation. For
encryption, Rijndael algorithm was used.
Keywords: Encryption,
Rijndael, DirectShow, Real-time, Wireless, Embedded
Title of the Paper: Identification of a
Continuous Linear Time-Varying System using Haar Wavelet with Unit Energy
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Authors:
S. J.
Park, K. J. Kim, S. W. Nam
Abstract: In this paper, identification of a continuous-time linear
time-varying (LTV) system is proposed, where Haar wavelet with unit energy is
employed. For that purpose, an algebraic equation is derived by expanding the
input-output data and the time-varying impulse response using normalized Haar
wavelets. Unknown wavelet coefficients for the a LTV system’s impulse
response can be effectively estimated by solving the algebraic equation.
Finally, the time-varying impulse response of a LTV system can be synthesized
from the estimated wavelet coefficients.
Keywords: Linear
time-varying system, impulse response, identification, Haar wavelet
Title of the Paper: A New Study in
Maintenance for Transmission Lines
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Authors: Lijia Ren, Xiuchen Jiang,
Gehao Sheng, Wu Bo
Abstract: Because of increasingly common damage and thefts of the
transmission towers, a new function is proposed to enhance the state
maintenance of transmission lines. It relies on the monitoring of the
high-voltage transmission towers to ensure the reliability and safety of the
power grid operation. An approach which combines Independent Component
Analysis (ICA) with neural network based on Particle Swarm Optimization (PSO)
algorithm is presented. Its purpose is to extract the vibration source
signals caused by the theft of the towers. Initially, the proposed algorithm
separates the source vibration signals from the observed mixing signals based
on the FastICA of negentropy and Exploratory Projection Pursuit (EPP). In
order to distinguish the vibration pulse signal from other similar
interference pulses, the algorithm of the feed forward neural network (FFNN)
is used to identify the vibration pulses. It is trained online with particle
swarm optimization (PSO), which incorporates the pulse extraction algorithm
based on an adaptive threshold. Numerical results show that the algorithm is
effective in extracting and identifying the vibration signals, and it also
can suppress the interference signals.
Keywords: Transmission
tower; ICA;
Negentropy; Adaptive threshold; Particle swarm optimization (PSO); Neural
network
Title of the Paper: Fuzzy Techniques in
Analog Circuit Design
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Authors: Gabriel Oltean
Abstract: The aim of his paper is to present some applications of fuzzy
techniques in the optimization-based design of analog circuits. Our approach
turns into profit the advantages offered by different fuzzy techniques. Fuzzy
systems or fuzzy sets are involved in every algorithm phase. The optimization
problem formulation is accomplished in a flexible manner using fuzzy sets to
define fuzzy optimization objectives. Also, the initial guess of design
parameters is based on matching degrees determined with fuzzy sets. The
optimization engines use fuzzy systems to compute the coefficients to modify
the design parameters in each iteration. In order to reduce the time spent
for circuit performance evaluation, we use a fuzzy system to model each
circuit performance. Two computer-aided design tools, at the cell level are
developed in Matlab. A large collection of experimental results proves the
validity of our approach. Different analog modules as simple transconductance
operational amplifier, Miller operational transconductance amplifier, and
common-emitter stage were designed for several sets of design requirements
with very good results.
Keywords: Analog design,
Multiobjective optimization, Fuzzy sets, Fuzzy systems, Unfulfillment degree.
Title of the Paper:
A Genetic Algorithm based Approach for
System-on-Chip Test Scheduling using Dual Speed TAM with Power Constraint
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Authors: Chandan Giri, Dilip Kumar
Reddy Tpparthi, Santanu Chattopadhyay
Abstract: Increasing complexity of System-on-Chip (SOC) has encouraged the
engineers to design versatile automated test equipment (ATE) that can drive
simultaneously different data channels at different data rates so that
overall test cost can be reduced. Devices like Agilent 93000 series tester
and Tiger system from Teradyne provide such flexibility to drive different
channels at different data rates. Number of tester channels with higher data
rate is limited due to different constraints like power rating of the SOCs,
limitation of scan frequency, complexity of ATE etc. Hence proper utilization
of the tester channels to reduce test time and thereby test cost is
important. In this paper we provide a Genetic algorithm based approach for
SOC-level TAM architecture optimization that minimizes testing time
considering two different data rates for ATE channels. Our approach achieves
better results than those reported in the literature. Experimental results
show that the maximum improvement of 40.99% in testing time can be achieved.
Keywords: System-On-Chip
test, Test scheduling, Test access mechanism, Dual speed, Power constraints,
TAM, Power-constrained testing.
Title of the Paper: High-PSR-Bandwidth
Capacitor-Free LDO Regulator with 50µA Minimized Load Current Requirement for
Achieving High Efficiency at Light Loads
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Authors: Huan-ChienYang, Ming-Hsin
Huang, Ke-Horng Chen
Abstract: A capacitor-free LDO regulator with the minimized-Q (MQ) and
adaptive zero compensation (AZC) techniques is proposed in this paper. With
the MQ technique, light load efficiency is greatly improved since only 50iA
minimized load current is required. Furthermore, due to noise cancellation
from power supply, the LDO regulator with the MQ technique has higher PSR
bandwidth with compatible compensation capacitors compared to the Q-reduction
technique [1]. Besides, fast transient response time is also achieved because
phase margin equals to 60 degree is always maintained by the MQ and AZC
techniques. The capacitor-free LDO regulator with the MQ and AZC techniques
was fabricated in TSMC 0.35im 2P4M CMOS process with small compensation
capacitors 5pF and 1.5pF. Experimental results demonstrate that the minimum
load can be reduced to about 50iA and transient response time can be reduced
by the MQ and AZC techniques to be smaller than 4is. The measured load and
line regulation are 20iV/mA and 3.3mV/V respectively.
Keywords: Capacitor-free
LDO regulator, minimum load, frequency compensation, PSR bandwidth, fast
transient response
Title of the Paper: Modeling and Design
of Control System for Variable Speed Wind Turbine in All Operating Region
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Authors: Wu Dingguo, Wang Zhixin
Abstract: In order to get the maximum power from the wind, the variable-speed
wind turbine should run at different speed when wind speed changes. In this
paper a control system is introduced to get this purpose base on establishing
the three-mass model of the wind turbine. The control system consists of two
parts: one is a speed controller for generator control; the other is a PI
controller for pitch control. Simulation results by using actual detailed
parameters for wind turbine show the effectiveness and robustness of this
control system.
Keywords: three-mass
model, feed-forward compensator, loop-shaping, speed controller, pitch
controller, wind turbine, doubly-fed induction generator (DFIG)
Issue 6, Volume 7,
June 2008
Title of the Paper: A Method for
Content-Based 3D Model Retrieval by 2D Projection Views
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Authors: Hang Xiao, Xiubin Zhang
Abstract: An effective approach for 3D model retrieval is to represent models
by a set of projection views . In this paper, we propose a flexible framework
for view-based 3D model retrieval. The framework provides users the ability
to configure three components: the number of views, the type of views, and
the 2D shape descriptors used to distinguish views. Because the three
components are closely related to the performance of a view-based 3D model
retrieval system and usually application-dependent, it is necessary to make
them configurable. To achieve this goal, the framework employs a new view
polyhedron positioning algorithm and provides an adaptable interface to its
3D shape feature extraction module. We build a demo 3D model retrieval system
based on the framework. Experiment shows that the performance of the demo
system is satisfactory.
Keywords: 3D model
retrieval, information retrieval, 3D shape analysis, model feature
extraction, viewbased models
Title of the Paper: Robust Control
Applied to Improve the Performance of a Buck-Boost Converter
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Authors: Wilmar Hernandez
Abstract: In this paper, H∞ loop-shaping control is applied to improve
the performance of a buckboost dc-dc power converter based on
pulse-width-modulation (PWM) techniques. Here, classical control techniques
(i.e., proportional-integral-derivative (PID) control) and post-modern
control techniques (i.e., H∞ control), are used to design the feedback
loop of a buck-boost dc-dc power converter. The results of the experiment are
satisfactory and show that robust controllers do not depend strongly on the
operating point, and that H∞ loop-shaping control performs better than
PID control.
Keywords: buck-boost
converter, state-space averaging procedure, robust stability, PID control, H∞
loop-shaping control, disturbance rejection
Title of the Paper: Technological
Process Optimisation and Process Characterisation in Relation to the Quality
Assessment
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Authors: Radovan Novotny
Abstract: In order to optimise and characterize technological processes for
quality planning, evaluation and development purposes must be used proper
methodology. Methodology for designed experiment and uncertainty can be one
possible way to do this. Variation and effect of various technological
factors in relation to the material structures stability, consistency and
overall performance in the relation to the important aspects related to the
observation and analysis of the influence more than one variable at a time on
the response of interest.
Keywords: multi-vari
analysis, variation, optimization, experiment, factor, response, design
Title of the Paper: Low Noise, Dual Gain
Preamplifier with Built In Spectroscopic Pulser for Highly Segmented
High-Purity Germanium Detectors
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Authors: G. Pascovici, A. Pullia, F.
Zocca, B. Bruyneel, D. Bazzacco
Abstract: We present a fast and very low noise hybrid front-end electronic
device consisting of a complex charge sensitive preamplifier with a built in
fast reset circuitry and a very accurate spectroscopy pulser. The front-end
electronics was developed for the central electrode of 36-fold segmented,
high purity germanium detectors in the frame of AGATA array of detectors. The
intrinsic energy resolution in conjunction with a highly segmented detector
is less then 900 eV for central electrode with a detector capacity of ~ 47
pF. The dynamic range of the central charge sensitive stage is as large as
100 dB, ranging from 0.1 fC to 10 pC, i.e. from ~2 keV to 180 MeV in terms of
photon energy. To achieve such an unprecedented wide dynamic range, we split
the whole spectroscopic range in four sub-ranges, namely 0-5 MeV, 0-20 MeV,
5-180 MeV and 20-180MeV, respectively. The first two ranges are measured with
standard pulse-high spectroscopy techniques. Thereto, the analog electronics
was designed with two conversions gains, 200 mV/MeV and 50mV/MeV,
respectively to match the 1 V input dynamic range of the very fast pipe line
ADC used by the digitizer units. To extend the pulse-height spectroscopy
range well beyond the fast ADC analog input range, a new method was
implemented and at a certain threshold we are switching from a standard pulse
height analysis method to a time over threshold technique [TOT]. In order to
achieve that, adjacently to the pole-zero cancellation circuit, a fast-reset
circuit controlled by a fast comparator and an accurate zero crossing
detector has been developed. Using this technique we can achieve an energy
resolution of 0.04% at equivalent gamma energies of 180MeV. A programmable
spectroscopic pulser has been designed and implemented in the central
electrode (core) front-end electronic to achieve ‘self-calibration standards’
in both time and amplitude domain, which was needed to characterize such a
complex, highly segmented high purity solid state detector.
Keywords: low noise, fast
preamplifier, tracking gamma spectroscopy, extended ADC range
Title of the Paper: Hardware
Accelerator for Evolutionary Robotics
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Authors: Masaya Yoshikawa, Hidekazu
Terai
Abstract: Evolution robotics is one of the autonomous learning and its
approaches have been applied to various fields. In this paper, we discuss new
evolutionary robotics technique. The proposed evolutionary robotics acquires
their behavior using genetic-based machine learning. It adopts new if-then
rules for learning algorithm. Moreover, it introduces novel hardware
accelerator in order to reduce simulation time for calculation, since the
genetics-based machine learning requires very long computational time.
Experiments using quasi-ecosystem demonstrate not only the effectiveness of
the proposed learning algorithm, but also that of the proposed hardware
accelerator.
Keywords: Evolutionary
robotics, Hardware accelerator, If-then rules, Genetic-based machine
learning, Quasi-ecosystem
Title of the Paper: Aspects Regarding a
New Method for the Optimal Control Law’s Synthesis of Aircrafts’ Move
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Authors: Lungu Mihai, Lungu Romulus,
Jula Nicolae, Cepisca Costin, Calbureanu Madalina
Abstract: The paper presents a new algorithm for optimal control law’s
synthesis in rapport with state vector of the aircraft’s move. Starting from
state equation of the movement, the system is brought to Jordan
canonic form and Riccati algebraic matricidal equation (whose solution is the
gain matrix of the control law) is brought to an equivalent form with
transformation relation. The new gain matrix is partitioned conform to
equations (35) ? (40). Using ALGLX algorithm, one studies elastic no deformed
(no dimensional description) longitudinal and lateral move of an aircraft and
dimensional elastic deformed move. One obtained Matlab/Simulink models and
numerical programs and with them time characteristics expressing state
variables’ dynamic are obtained.
Keywords: algorithm,
optimal, control law, longitudinal and lateral move, synthesis
Title of the Paper: Optimal Control of
Flying Objects’ Move After Estimated State Vector Using a Reduced Order
Observer
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Authors: Lungu Mihai, Lungu Romulus,
Jula Nicolae, Calbureanu Madalina, Cepisca Costin
Abstract: In this paper one presents an algorithm for project of a reduced
order observer (ALGLOOR) with applications to flying objects’ move. The
command law is an optimal one in rapport with state vector of the observer.
Numeric calculus examples are also presented: for longitudinal and lateral
move and vertical move of a rocket in vertical plane in rapport with equal
signal line; using Matlab/Simulink model of closed loop system one has made
numeric calculus programs and with them one obtained different time
characteristics, which expresses state variables’ dynamics of the flying
objects dynamic models.
Keywords: algorithm,
optimal, control law, rocket, state vector, reduced order observer, command
Title of the Paper: A Unified Treatment
of Deterministic and Random Transients in Electrical Circuits
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Authors: Sabin Ionel, Virgil
Tiponuţ, Catalin Caleanu, Ioan Lie
Abstract: The continuity of capacitor voltages and inductor currents,
well-known from the deterministic case, cannot be directly applied if the
initial conditions are random. In this paper, new continuity relations for
probability densities, mean values, correlation and covariance functions of
the state variables are introduced. These continuity relations can be used
for a global characterization of random transients. New formulas for initial
condition and forced components of transient statistical moments are also
presented. These formulas offer a direct approach for random transient
analysis. Deterministic transients can be regarded as particular,
degenerated, random transients. On this basis, one can develop a unified
treatment of deterministic and random transients in electrical circuits. This
unified framework is certainly an advantage, not only in teaching activities
related to transient phenomena.
Keywords: Electrical
circuit, Initial condition, Random transients, Statistical moments,
Continuity relations
Title of the Paper: Optimum Sway
Control for Overhead Traveling Cranes
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Authors: Kamal A. Khandakji, K. P. Zdrozis
Abstract: Sway control for industrial applications and for cranes
particularly is a historical problem that has accompanied the development in
power semiconductors since the 1980’s. This article proposes a power
semiconductor drive system, which can be used in the anti-sway control of
overhead cranes driven three-phase induction motor. The developed system is
based on the rotor current control. The proposed power semiconductor drive
system is simulated using the developed comprehensive mathematical model. The
performance of the proposed systems is analyzed and compared to
voltage-controlled anti-sway system. A prototype of the proposed anti-sway
control system is developed at the laboratory of electric drives and
automation in ATEI – Greece,
while the mechanism prototype was developed by the project sponsor - Arab
Manufactures Company in Amman
– Jordan.
Keywords: Anti-sway
control, overhead traveling cranes, controlled current converter, three-phase
induction motor.
Title of the Paper: Robustness of
Systems with Various PI-like Fuzzy Controllers for Industrial Plants with
Time Delay
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Authors: Snejana Yordanova
Abstract: The robustness of the systems with fuzzy logic controllers (FLC)
has lately focused the attention of researchers in relation with the
expansion of their industrial application. The contemporary complex,
nonlinear, time varying processes with time delay and various disturbances
and the high demands for their control require to account for system
stability and robustness in the FLC’s design. The simplicity of the design is
of great importance in connection to its easy practical application. The aim
of the present investigation is to develop a generalised procedure for the
design of various PI-like FLCs with regard to system performance robustness
and to compare the robustness of the control systems. The approach is
developed for PI incremental and position FLCs based on the single input
fuzzy controller (SI FC), Popov stability and Morari robustness and considers
the control of industrial plants with time delay and model uncertainty. The
main contributions are: 1) a generalised design procedure for FLCs accounting
for system stability and robustness; 2) FLCs’ general tuning algorithm. The
results are applied for the stabilisation of the air temperature in a furnace
using MATLAB™. The performance of the designed FLC systems is assessed and
compared to the performance of control systems with internam model controller
via simulations.
Keywords: Frequency
domain PI-like process FLC design, MATLAB, robust performance, temperature
control, time delay, tuning algorithm
Title of the Paper: Noise-based Wavelet
Denoising Technique for Partial Discharge Measurement
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Authors: Zhou-Sheng Zhang, Deng-Ming
Xiao
Abstract: For enhancement the insulation quality of medium voltage and high
voltage power cables, on-site partial discharge (PD) diagnosis tests such as
detection, location and identification are used to find defects or faults and
assess ageing degree of the cable insulation. Typical test methods such as
oscilating voltage waves (OVW), very low frequency (VLF) for medium cables
and frequency-tuned resonance (FTR) for high voltage cables are adopted by
far, especially for XLPE cable system. However, on-site interferences and
noises make this PD detection very difficult. It requires a better method to
extract PD pulses from severe noise circumstance. Wavelet transform technique
used to suppress noises from PD signal (PDs) requires reasonable mother
wavelet, amount of scales and thresholds to produce its best effect. This
paper proposed a new wavelet-based denoising technique for on-site PD
measurement of power cables. It aimed at applying discrete wavelet transform
(DWT) with better denoising effect to on-site PD measurement. Firstly, it described
and analyzed the testing methods for on-site PD measurement. Secondly,
resonable amount of scales selection algorithm and threshold determine
algorithm have been studied with this denoising technique. Finally,
simulation studies associated with this method are presented. Moreover,
previous wavelet denoising techniques are also studied here to compare to the
new technique. Results indicate that this technique can not only attain
better denoising effect but also improve the sensitivity of PD detection.
Keywords: Partial
discharge, discrete wavelet transform, power cables, oscilating voltage wave,
very low frequency, frequency-tuned resonance.
Title of the Paper: An Active Islanding
Detection Method for Small-Scale Distributed Generators
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Authors: Wen-Yeau Chang
Abstract: This paper proposes a new islanding detection method for use in a
small-scale, grid-interconnected distributed generator system. The proposed
islanding detection method is based on voltage fluctuation injection, which
can be obtained through high-impedance load switching on the grid
periodically. The correlation factor between the periodic switching signal
and the perturbed voltage is then used as an islanding detection index in the
proposed islanding detection method. Experimental results demonstrate the
principles of the proposed technique and show the new proposed method is
reliable, economical, and easy to implement.
Keywords: Islanding
detection, Distributed generator, Voltage fluctuation injection, Correlation
factor
Title of the Paper: An Efficient
Scheduling Algorithm based on Multi-Frequency TAM for SOC Testing
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Authors: Jiann-Chyi Rau, Po-Han Wu,
Jia-Shing Ma
Abstract: In recent years the advance of CMOS technology has led to a great
development, especially on the complexity of the system-on-chip (SOC). As the
development of circuit with different technology, the embedded cores embedded
into system-on-chips (SOCs) usually have multi-frequency to drive it. In this
paper, we present a heuristic approach of TAM optimization according to the
reality and reduce the test application time. The proposed method is
applicable to the design model with hierarchy SOCs. We pay the price in
hardware overhead in order to decrease test application time.
Keywords: SOC, Testing,
TAM
Title of the Paper: Analysis of Signals
Characterization of Circuits on the Traction Power Systems
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Authors: Ying-Tung Hsiao, Kuang-Chieh Lin
Abstract: In this paper present the characteristics of the signals and ripple
harmonics in the circuits of the traction power systems of the
Taipei mass rapid
transit system. This analysis provides a novel simulation method, using
Matlab software program application to the signals and ripple and harmonics
simulate. This investigation uses a reality circuits and systems to simulate
the DC traction power system operation for the Taipei metro systems. The analyses discover
that the ripple harmonics and operation waveform affect the circuits of the
power system design, feature and regulation, and influence on the operation
stability of the DC-link between the traction power and vehicle propulsion
systems. The simulation data can observe the typical harmonic characteristics
for the behavior of the DC traction power systems. This study reveals the
running waveforms of the traction power rectifier and vehicle propulsion
system operation that can be precise control and regulation. This analysis
results of the characteristic of the operation waveform and ripple harmonics
in the DC link systems can help engineers to identify system design and after
maintenance regulation.
Keywords: harmonics,
ripple, inverter, converter, DC link, traction power system.
Title of the Paper: SUT-CARG Car-Like
Robots: Their Electronics and Control Architecture
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Authors: Suchart Punpaisarn, Sarawut
Sujitjorn
Abstract: This article presents the development of the SUT-CARG car-like
robot system. CARG car-like robots consist of four mobile robot agents and
are built as integrated systems with IR, sonar, ultrasonic, vision sensors
and controller modules. Hardware details are given. The software interface
module for commanding the robots is described. The article also presents the
details of robot following control which utilizes geometrical control
approach based on vision and image processing. Colour tracking and flocking
of the robot agents are demonstrated (VDO available online
http://www.sut.ac.th/engineering/electrical/carg/).
Keywords: Car-Like Robot,
Visual Servo, Image Processing, Colour Tracking, Robot Following Control,
Flocking.
Issue 7, Volume 7,
July 2008
Title of the Paper:
Neural Design Procedure for an ATTR System based on Video Imagery Usage
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Authors: Constantin-Iulian Vizitiu,
Petrica Ciotirnae
Abstract: It is well known that the design and effective development of ATTR
systems incorporating in their architecture some characteristic elements
belong to artificial intelligence represents and will represent a very
important research direction in this area. Accordingly, in the current study
a specific design algorithm for a full neural implementation of an ATTR
system based on video imagery usage is described. Using an actual database,
the theoretical and experimental results obtained confirm the great potential
of the proposed design algorithm to be implemented into concrete ATTR
application.
Keywords: ATTR system,
pattern recognition, neural networks, video imagery
Title
of the Paper: An Adaptive Channel Parameter Estimation Using QQ-plot
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Authors: Z. Djurovic, I.
Kovacevic, B. Kovacevic
Abstract: New algorithm for estimation of parameters of communication channel
in the circumstances of existence of intensive impulse noise within measurement
sequence is proposed in this paper. Proceeding from the theory of robust
estimation, a simple, adaptive, practically applicable algorithm is derived
that in the circumstances of contaminated normal distribution of measurement
noise demonstrates high level of efficiency. QQ-plot technique is used as a
framework for estimation of contaminated measurements distribution providing
the algorithm adaptation. Application of proposed algorithm is broad, both in
the field of wireless communications, equalization of transmitting channels,
suppressing of noise and in modeling communication and control systems.
Keywords: Channel
identification, robustness, adaptation, QQ-plot
Title of the Paper: MIMO
U-model Based Control: Real-Time Tracking Control and Feedback Analysis via
Small Gain Theorem
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Authors: Ali Syed Saad Azhar, Fouad M.
Al-Sunni, Muhammad Shafiq, Jamil M. Bakhashwain
Abstract: In this paper, MIMO U-model based IMC is used for the tracking
control of multivariable nonlinear systems. The algorithm is implemented in
real-time on a 2DoF robot arm. The stability and convergence issues for the
control-oriented U-model are also discussed. In order to guarantee stability
and faster convergence speeds, bounds are suggested for the learning rate of
adaptation algorithm that estimate the parameters of U-model. The adaptation
algorithm is first associated with a feedback structure and then its
stability is investigated using l2 stability and small gain theorem. The
paper also discusses about the robustness of adaptation algorithm in the
presence of noise and suggests optimal choices for faster convergence speeds.
Keywords: U-Model, LMS,
Convergence Speed, Learning Rate, Small Gain Theorem
Title of the Paper: Utilization
of Soft Computing to Improve Cooperative Management Efficiency
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Authors: Seyed A. Shahrestani
Abstract: Provision of collaborative services requires cooperation among
various entities of an organization. Furthermore, efficient management of any
complex system, such as large enterprises or modern enterprise networks,
depends on understanding the roles of its constituents and their interactions
with one another. Interaction of humans is partially or fully dictated by
their level of awareness of the capacity that others have in supporting them
in fulfilling the tasks at hand. As such, awareness modelling and levels can
play significant roles in improving the management efficiency. The awareness
levels in human beings and managers have a fuzzy nature with linguistic
variables extensively used in their characterizations and communications.
Noting the underlying fuzziness, this paper explores how soft computing can
be used to improve awareness modelling to achieve more effective cooperative
management. This is further demonstrated through its application to an
illustrative example that utilizes fuzzy proximity networks.
Keywords: Soft Computing,
Fuzzy logic, Cooperative Management, Network Management, Awareness Modelling.
Title
of the Paper: New Ways for Terology through Predictive Maintenance in an
Environmental Perspective
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Authors: Torres Farinha,
Inacio Fonseca, Antonio Simoes, Maciel Barbosa, Jose Viegas
Abstract: Terology is defined as the combined use of techniques of
operational research, information systems and engineering, with the objective
of accompanying the life cycle of facilities and equipments; it includes the
definition of specifications referred to its purchase, installation and
reception, as well as the management and control of its maintenance,
modification and substitution and, still, its accompaniment in service. Under
this perspective, maintenance is the core of terology and it correspond a
subject that, instead of reducing importance of maintenance with the
increasing of equipment reliability, it increases its role in the companies
and obliges the increasing of the level of demand of professionals involved
because of the new technical and environmental demands. This reveals the
importance of this scientific area and the necessity to concentrate and to
increase the research around it. The maintenance area is an example that
offers challenges to both science and companies in order to optimize the
performance of equipment and facilities. But, the scientific developments,
namely in this area, must be more and more environmentally friendly or, in
other words, must close the technology to nature, guarantying its life
through an adequate maintenance management. It is because of this kind of
challenge that the authors are developing new methodologies, almost
antagonistic, because of the areas under development, namely diesel engines
and wind generators, but as we will demonstrate, areas which are compatible
and can contribute for a better environment. In the case of wind generators,
the methodology aims to optimize the cycles of production and, consequently,
reduce the other kinds of energy production. On the other hand, the
methodologies for maintenance of diesel engines are based on environmental
indicators that can predict the “health state” taking into account
restrictions including health human factors among others. The new
methodologies will later be incorporated through new predictive maintenance
modules in an integrated maintenance management system called SMIT (Terology
Integrated Modular System). The SMIT was developed as a traditional system,
but it includes several innovations, like a fault diagnosis module, a
non-periodic maintenance planning module and a generic on-condition
maintenance module, among others. The new features will include, in the case
of wind generators, on-line measures and the corresponding on-time treatment,
using algorithms based on time-series forecasting and TCP/IP technology to
transmit the signals. In the case of diesel engines, the algorithms are based
on Markov chains and hidden Markov chains. It is based on these developments
and the new researches mentioned so far, that this paper is built upon, and
we believe that it will be a contribution to the maintenance management area.
Keywords: Terology;
Maintenance management; Predictive maintenance; Diesel engines; Wind
generators
Title of the Paper: Fast Stereo-based
Visual Odometry for Rover Navigation
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Authors: Aldo Cumani, Antonio Guiducci
Abstract: The object of visual odometry is the computation of the path of a
rover from onboard passive vision data only. The approach presented here
relies on the accumulation of ego-motion estimates obtained by stereo vision
and bundle adjustment of tracked feature points. We also propose a new
feature detector/descriptor, which is a simplified and faster form of other
well known descriptors (SURF). For cyclic paths, a d/ej`a vu mechanism allows
further control over the accumulated error. Tests on real-world data show
that our descriptors are effective for accurate path estimation, while being
fast enough for use in tasks such as autonomous planetary exploration.
Keywords: Robot localisation,
Stereo vision, SLAM, Hessian feature detectors
Title of the Paper: Use of An
Equivalent Thermal Network for the Analysis of a Coupled Thermo-Magnetic
problem
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Authors: Francesco Della Torre, Sonia
Leva, Adriano Paolo Morando
Abstract: The coupled magneto-thermal problem is analyzed, with reference to
a particular heating application, by means of an equivalent thermal network,
that is based on a first-approximation interpretation of the field equations.
The connections between the thermal characteristics and the magnetic ones are
taking into account by considering the skin-effect and the dependence of
electric conductibility on the temperature. Also the dependence of the
produced heat – by Joule effect – on frequency is taken into account. A
specific and straightforward applicative case is analyzed in order to
underline the validity and the advantages of the proposed model. A single
conductive loop is lighting by an impressed perpendicular magnetic field and
both the forward and inverse problems are analyzed. An integration technique,
based on Matlab-Simulink, is shown for the solution of the problem. Moreover,
the dependence of the achieved results on the geometric characteristics of
the analyzed system is studied.
Keywords: Electroheat
applications, Coupled thermo-magnetic problem, Numerical method, Thermal
network
Title of the Paper: Neuro - Adaptive
Command Systems for Very Maneuverable Flying Objects
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Authors: Lungu Mihai, Lungu Romulus,
Jula Nicolae, Cepisca Costin
Abstract: One presents a dynamic model of the very maneuverable flying objects
(A), which expresses the dependence between the vector formed by angles of A
regarding aerodynamic trihedron and the vector of angular velocities of A or
the vector of linear acceleration components in rapport with the trihedron
related to A. Control structures (stabilization of movement) are also
presented. These consist of loops after angles, angular velocities and linear
accelerations and an adaptive control loop with neuronal network for dynamic
inversion errors compensation of the non-linear function which describes
unknown system of the dynamic model of A. Adaptive command is projected upon
stability theory using Liapunov functions [1], [2], [3]. As calculus examples
one presented two systems and stabilization models of the very maneuverable
rocket’s longitudinal move [4]. Time evolution of the attack angle for the
studied cases is also presented.
Keywords: dynamic model,
adaptive command, neuronal network, rocket, maneuverable
Title
of the Paper: Systems for Move Stabilisation and for Aircrafts and Rockets
Flight Optimization
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Authors: Lungu Mihai, Lungu Romulus,
Jula Nicolae, Cepisca Costin
Abstract: This paper deals with models of the rockets’ motion around mass
centre, command laws of vertical and horizontal planes trajectory,
stabilisation laws of the roll motion of the rockets and target control laws
[1], [2]. One also studies the way to choose of the parameters of general
command laws which assures state variables simultaneous cancellation. Some
automatic control systems, using the previous laws, are also presented. Also,
one presents some extremal systems for optimization of aircrafts and rockets’
flight using test signals for extreme’s search [3], [4].
Keywords: rocket, command
law, target, control, extremal system, testing signal
Title of the Paper: Bifurcation and
Chaotic Aspects in Peak Current Controlled Buck-Boost Converters
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Authors: Dan Negoitescu, Dan Lascu,
Viorel Popescu, Corina Ivan
Abstract: The paper investigates the bifurcation and chaotic behavior of a
current-mode controlled Buck- Boost converter operating in continuous
conduction mode (CCM). The analysis comprehends both open loop and
proportional closed loop operation cases. Classical averaged dynamic models
cannot predict the chaotic converters behavior which leads to typical
phenomenology like period-doubling, quasiperiodic and chaotic operation. The
most important dynamic behavior aspects are revealed by simulation, together
with a rigorous mathematical description that exactly predicts the converters
operation modes.
Keywords: Non-Linear
dynamics, bifurcation, chaos, subharmonic oscillation, dc-dc converters,
buck-boost converter, current-mode control, power electronics
Title of the Paper: Diagnosis and Repair
Method of SoC Memory
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Authors: Vladimir
Hahanov, Anna Hahanova, Svetlana Chumachenko, Sergey Galagan
Abstract: An exact method of memory elements diagnosis and repair by spares
that enables to cover a set of fault cells by minimally possible quantity of
spares is represented. The method is oriented on implementation to the
Infrastructure Intellectual Property for SoC functionality. It enables to
raise yield essentially on the electronic technology market by means of faulty
chip repair in the process of production and operation, as well as to increase
the life cycle duration of memory matrixes by repair of them in real time.
Keywords: Diagnosis,
System-on-Chip, Built-In Repair Analysis, Built-In Self Repair, Fault,
Simulation.
Title of the Paper: Algebra-Logical
Diagnosis Model for SoC F-IP
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Authors: Vladimir Hahanov, Vladimir
Obrizan, Eugenia Litvinova, Ka Lok Man
Abstract: Algebra-logical model, method and algorithm of fault embedded
diagnosis in functional blocks of SoC are proposed. The reduced SoC
Functional Intellectual Property Infrastructure that is characterized by
minimal set of the embedded diagnosis processes in real time and enables to
realize the services: testing of the nominal functions on basis of generable
input patterns and analysis of output reactions; fault diagnosis with given
resolution of fault location by means of utilization of the IEEE 1500
multiprobe; fault simulation to provide of realization of the first two
procedures on basis of the fault detection table is presented.
Keywords: Diagnosis,
System-on-Chip, Electronic System Level, Transaction Level Modelling,
Infrastructure Intellectual Property, Functional Intellectual Property,
Testbench, Fault
Title of the Paper: Selective
Encryption Techniques of JPEG2000 Codestream for Medical Images Transmission
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Authors: Zahia Brahimi, Hamid Bessalah,
A. Tarabet, M. K. Kholladi
Abstract: In this paper, novel selective encryption image schemes based on
JPEG2000 are proposed. The first one encrypts only the code-blocks
corresponding to some sensitive precincts. In order to improve the security
level we introduce the permutation of codeblocks contributing in the selected
precincts. The idea of combining permutation and selective encryption is used
in order to minimize the amount of processed data encryption while ensuring
the best possible degradation through the permutation. Many of proposals
format compliant encryption schemes for JPEG2000 that have been made encrypt
packet body data, but leave header packet in plaintext. The second approach,
combines code-blocks data encryption to a cyclic permutation of all packets
headers in the bitstream. Actually, in the JPEG2000 codestream, packet header
information is specific to the visual content, and it is can be used as a
fingerprint of the codestream. Symmetric encryption AES with CFB mode is used
to encrypt in the two schemes. The proposed schemes don’t introduce
superfluous JPEG2000 markers in the protected codestream, i.e, its format is
compliant to JPEG2000 codestream one. It keeps file format and compression
ratio unchanged and doesn’t degrade the original error robustness. The
proposed scheme works with any standard ciphers and introduces negligible
computational cost.
Keywords: Communication
system security, JPEG2000 Compression, Selective Encryption, permutation,
medical images, Computer applications.
Title of the Paper: Optimal Voltage
Assignment Approach for Low Power using ILP
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Authors: Yu-Cheng Lin, Hsin-Hsiung
Huang, Cheng-Chiang Lin, Tsai-Ming Hsieh
Abstract: In this paper, we proposed an optimal voltage assignment approach
which determines the proper voltage for each gate in the gate level netlist
using dual supply voltages. To the best of our knowledge, it is the first
work to integrate the impact of the level shifters into the integer linear
programming (ILP) formulations. The objective of the paper is to minimize the
total power, including the gates and the level shifters, under the given
delay constraints. For the gate level netlist, the voltage assignment
approach, which determines the delay for gates and wires and the power for
the gates and level shifters, is proposed. To reduce the runtime for the ILP
constraints, we also propose the node-based concept to formulate the timing
constraints. Finally, we optimally assign the voltages for all gates. The ILP
formulations are solved by using the ILP solver (LINGO 10.0) and the
experimental results with ISCAS circuits indicate the significant improvement
on total power using the dual supply voltages.
Keywords: Dual Voltage,
Low Power, Timing Constraint, Integer Linear Programming, Delay, Optimal
Title of the Paper: Different Methods
for Direct Torque Control of Induction Motor Fed From Current Source Inverter
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Authors: Aleksandar Nikolic, Borislav Jeftenic
Abstract: Two different methods for direct torque control (DTC) of induction
motor fed from current source inverter (CSI) is analyzed in the paper. The
first one is derived from well-known DTC strategy developed for voltage
inverter drives. This type of control basically uses hysteresis type
controllers for torque and flux. In CSI drive there is only one controller
used for torque control loop. The problems that arises in such a drive is
significant torque pulsations due to the nature of CSI and occasional speed
drops because of variable switching frequency. The other DTC method, proposed
in the paper, is based on constant switching frequency with modification of
the inverter optimal switching table. Further improvements are reduced number
of sensors since all measurements are performed in DC link only and in flux
estimator. Both simulation and experimental results shows that this algorithm
has better performance without problems that exist in the same drive with
torque hysteresis comparator. Finally, proposed method is simpler for
implementation in a real drive without rotational transformation and
parameter dependences that exist in vector control of the same drive.
Keywords: DTC, hysteresis
comparator, constant switching, CSI, induction motor
Title of the Paper: FPGA-based
Real-Time Implementation of an Adaptive RCMAC Control System
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Authors: Chih-Min Lin, Chao-Ming Chung, Chun-Fei Hsu
Abstract: The main
advantage of the recurrent cerebellar model articulation controller (RCMAC) is
its rapid learning rate compared to other neural networks. This paper proposes
an adaptive RCMAC control system for a brushless DC (BLDC) motor. The proposed
control scheme is composed of an RCMAC controller and a robust compensator.
The RCMAC controller is used to mimic an ideal controller, and the robust
controller is designed to compensate for the approximation error between the
ideal controller and the RCMAC controller. The Lyapunov stability theory is
utilized to derive the parameter tuning algorithm, so that the stability of
the closed-loop system can be achieved. As compared with standard adaptive
controller, the proposed control scheme does not require persistent excitation
condition. Then, the developed adaptive RCMAC control system is implemented on
a field programmable gate array (FPGA) chip for controlling a brushless DC
motor. Experimental results reveal that the proposed adaptive RCMAC control
system can achieve favorable tracking performance. Since the developed
adaptive RCMAC control system uses a robust compensator to compensate for the
approximation error, there is no chattering phenomenon in the control effort.
Thus, the proposed control system is more suitable for real-time practical
control applications.
Keywords: BLDC,
FPGA implementation, RCMAC, adaptive control, Lyapunov function, neural
control
Title of the Paper: A Second Order
Autoregressive based Technique for Pipeline Leak Detection.
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Authors: Marllene Daneti
Abstract: Efficient leak detection techniques need to be characterized both
by rapidity and robustness. This paper studies a simple detection method
based on the second order autoregressive (AR) parameters of the pipeline
signals- a trade-off between the two required characteristics. The
theoretical geometrical positions defined by the AR coefficients are
developed for some particular cases of interest. The resulted model proves to
be in concordance with the experimental data. The algorithm is next tested under
non-stationary burst-type conditions induced both soft and hard, indicating a
good stability in comparison with the basic most inexpensive computational
detection method. The area under the Receiver Operating Characteristics (ROC)
curves indicates also a better performance of the proposed detector.
Keywords: Leak detection,
pipeline monitoring, AR models, ROC curves.
Title of the Paper: Design Optimization
of Discrete-time Single-Loop Sigma-Delta ADCs via Nonideality and Power
Analyses
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Authors: Fu-Chuang Chen, Meng-Syue
Li
Abstract: A conventional SD ADC design approach is a time consuming process
and needs much trials and errors. An optimization algorithm for the
discrete-time single-loop SD ADCs design is proposed. Circuit nonideality
models are derived in output noise power forms through a systematic circuit
imperfection study. A power model is also presented in order to estimate relative
power consumption. These models reveal that design parameter variation can
potentially affect several noises and errors in different ways, and may
change system power consumption. This design complexity is qualitatively
summarized into a table. Model completeness allows us to propose an
optimization algorithm to search globally for a design parameter combination
which meets SNR requirement while minimizing power consumption. Our
optimization algorithm is tested against two published design results, and is
verified by behavior simulations. Comparisons with
behavioral-simulation-based optimization approaches are also made.
Keywords: Sigma delta
modulator, noise model, power model, optimization.
Issue 8, Volume 7,
August 2008
Title of the Paper: Distributed
Simulation and Profiling of
Multiprocessor Systems on a Chip
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Authors: Zdenek Prikryl,
Tomas Hruska, Karel Masarik
Abstract: Embedded systems – multiprocessor systems on a chip with
application specific instruction-set processors (ASIPs) – become indivisible
part of our everyday lives. They are everywhere. Therefore, powerful and
flexible way of design and simulation of these systems is needed. The
simulators of ASIPs are created using an architecture description language
called ISAC. In this paper, the basic concept of simulation, the
communication protocol among ASIPs and the three-state synchronization
protocol that is used in the distributed multiprocessor simulation are
described. Further, the basic concept of profiling and consequential
evaluation of profiling information is described. One needs the results from
the simulation itself and the results from the profiling to find bugs in the
system and to optimize the system as a whole.
Keywords: Application
specific instruction-set processor, multiprocessor system on a chip,
simulation, simulator, synchronization protocol, communication protocol,
profiling, ISAC.
Title of the Paper: Impact of Voltage
Source and Initial Conditions
on the Initiation of Ferroresonance
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Authors: Kruno Milicevic, Ivan Rutnik, Igor Lukacevic
Abstract: The impact of voltage source and initial conditions on the
initiation of ferroresonance is investigated. The investigation is carried
out by simulating the behaviour of the mathematical model of ferroresonant
circuit realized in the laboratory. The initiation of ferroresonance is
investigated by varying the values of phase shift and amplitude of voltage
source in order to incite the ferroresonance. Thereby, the initial conditions
are varied within a practically possible range of initial values of
transformer voltage and transformer flux linkage.
Keywords: Ferroresonance,
Iron-cored reactor, Bifurcation diagram, Chaos, Nonlinear circuits
Title of the Paper: An Enhanced
Congestion-Driven Floorplanner
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Authors: Yu-Cheng Lin, Shin-Jia Chen,
Ping-Liang Chen, Hsin-Hsiung Huang
Abstract: In this paper, a
rectilinear-based congestion-driven floorplanning algorithm is presented to
enhance the wire congestion and the CPU runtime. The proposed algorithm
contains two stages, including the simulated-annealing (SA) based approach
with the concept of ant algorithm (SANTA) and the nonlinear programming based
method. The objective of the first stage and the second stage are to minimize
the multiple objectives, such as the area, wire length and wire congestion,
and to further improve the wire congestion of the local congested region
without the area overhead, respectively. First, the effective concept of the
ant algorithm is integrated into the multiple objectives floorplanner, which
simultaneously minimizes area, wire congestion and the total wire length, to
speedup the runtime. Besides, the nonlinear programming (NLP) based
formulations are provided to perform the module reshaping, which maximizes
the common length between two adjacent congested modules. For the
floorplanner, the sequential-pair (SP) presentation is utilized to deal with
the floorplan data at every iteration. For each iteration of the
floorplanner, we first use SANTA to improve the neighbor searching and reduce
the runtime. After performing the first state, we will obtain a floorplan
with the objectives of the area, wire congestion and total length. For the
intermediate floorplan, we select the two adjacent soft modules located at
the most congested regions and divide the two soft modules into a set of
connected sub-rectangles. Hence, we further reduce the congestion by
enlarging the common boundary between the selected adjacent modules. Of
course, the modular reshaping technique significantly increases the common
length and the capacity of pins to reduce the wire congestion by utilizing
the nonlinear programming based approach. To deserve to be mentioned that
there is no area overhead after we perform the modular reshaping for the
selected adjacent modules. Compared to the results of the traditional SA,
SANTA achieves an average
improvement on the area, the total wire length and CPU runtime by 3% and 8.1%
and 23.0%, respectively. To show the superior to our approach, 30 floorplan
samples are randomly selected from Microelectronics Center of North Carolina
(MCNC) benchmarks. The experimental result shows that the reshaping method
improves the wire congestion and total wire length by 22% and 1.54%,
respectively.
Keywords: Simulated annealing, Ant algorithm, SANTA, NLP,
Module reshaping, Floorplan
Title of the Paper: Image Contrast
Enhancement using Morphological
Decomposition by Reconstruction
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Authors: Ioan Jivet, Alin Brindusescu, Ivan Bogdanov
Abstract: The paper presents a novel
algorithm for the computation of the image decomposition using a morphological
filter with reconstruction The target applications are image contrast
enhancement especially those with high dynamic content. Both bright and dark
regions contrast enhancement were considered. A new hardware efficient
implementation of decomposition is presented. Following decomposition in 5
levels of detail a local contrast enhancement is performed. The new
reconstruction algorithm and its hardware implementation as proposed is shown
to be independent on structural element size and that it results in a
predictable time frame operation. A mixed schematic and VHDL/Verilog
description of the decomposition filters was synthesized and results show far
higher speed performance compared with solutions found in recent literature.
The FPGA implementation had as main objective real time operation. The
performance of the architecture was found to exceed real time conditions of
operation and fit into medium size FPGA. A test sample image was used for
contrast enhancement schemes validation. The white areas local contrast was
enhanced expanding the gray scale for the detail levels after a parabolic
series. The scale warping in the white areas resulted in contrast enhancement
while the dark areas did not.
Keywords: image filtering,
multi-dimensional kernel, FPGA implementation
Title of the Paper: A Coin Detection
System by Coupled Printed Spiral Inductors
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Authors: Junichi
Fukatani, Sho Yamaguchi, Masayuki Yamauchi, Kazuhisa Yoshimatsu, Hisashi
Aomori, Mamoru Tanaka
Abstract: This paper describes a coin
detection system using coupled Printed Spiral Inductors (PS-Inductors). In
this research, the PS-Inductor is composed of copper foil spiral on the
printed board. As an advantages, the PSInductor can be made easily and does
not need the iron core. The experimental measurement and the theoretical
calculation of the inductance of the PS-Inductor are derived. This enables
the easily realizable coin detection system using PS-Inductor. In this
system, a coin can be identified as changes of the mutual inductance of
coupled PS-Inductors. The mutual inductance is investigated by inserting the
coin between two PS-Inductors.
Keywords: Coin detection, Mutual
inductance, Printed Spiral Inductor, Combination inductance, Self-inductance
Title of the Paper: Analysis of Some
Solutions that Improve Performances of Plate-Type Electrostatic Precipitators
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Authors: Gabriel Nicolae
Popa, Ioan Sora, Victor Vaida, Iosif Popa, Sorin Deaconu
Abstract: The plate-type electrostatic
precipitators are use in burning industry applications and can treat large
gas flows. The paper presents the maximum ionization distance, analytic and
graphic, near discharge wires depending on the voltage supply frequency and
the discharge wires radius. A problem of this type of precipitator is
difficulty to collection high resistivity fly ash. In the inlet section the
fly ash resistivity is moderate and is necessary to charge dust particles as
many is possible. It is useful to use traditional dc energization. For the
middle section and especially for outlet section, where the fly ash
resistivity is high, it is necessary another supply solution for section
because the charging particle decrease when is use traditional dc
energization. The paper presents analysis of different types supplies of ESP
sections. The intermitent energization of sections can be a cheap solution to
middle and outlet section (without change the power supply structure, it is necessary
the change of the automatic voltage control unit). It is important to know
the current-voltage characteristics to obtain the optimal control of the
amplitude, the voltage shape, the input power and the collection efficiency.
With comparative analyze of the measured and computed characteristics, with
different mathematical model of current-voltage characteristics, it can be
found which models estimate the current-voltage characteristics for
plate-type electrostatic precipitators.
Keywords: plate-type electrostatic
precipitators, dc energization, intermitent energization, current-voltage
characteristics, mathematical models
Title of the Paper: VLSI Architecture
Design Approaches for Real-Time Video Processing
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Authors: A. Ahmad, K. K.
Loo, J. Cosmas
Abstract: This paper discusses the
programmable and dedicated approaches for real-time video processing
applications. Various VLSI architecture including the design examples of both
approaches are reviewed. Finally, discussions of several practical designs in
real-time video processing applications are then considered in VLSI
architectures to provide significant guidelines to VLSI designers for any
further real-time video processing design works.
Keywords: Dedicated, programmable, Very
Large Scale Integration (VLSI) architecture, video processing
Title of the Paper: Design and
Synthesis of a Configurable Fractional Order Hold Device
for Sampled-data Control Systems
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Authors: Koldo Basterretxea, Rafael
Barcena, Unai Ugalde
Abstract: Zero-order hold devices
(ZOH) are mainly used in digital control applications to obtain the output
analog signals of digitally implemented controllers. However, it is proved
that special hold devices such as the fractional order hold device (FROH) can
improve, if properly tuned, the performance of hybrid control systems.
Although the applicability of these devices has been theoretically studied in
numerous works, there is no report of real experimentation with digital
controllers that include special hold devices for the control signal
interpolation. This lack of real application experiments is mainly due to the
difficulties encountered in implementing such hold devices with the
processing speed and configurability that real-time digital controllers
require. This paper describes a totally configurable digital design of a FROH
device, adequate for any digital control system platform. The implementation
of an 8-bit resolution FROH prototype has been carried out and its
performance tested on a field programmable gate array (FPGA).
Keywords: Hold device, FROH, configurable
hardware, FPGA, digital controller, D/A conversion
Title of the Paper: A Multi-layer
Obstacles-Avoiding Router Using X-Architecture
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Authors: Yu-Cheng Lin, Hsi-An Chien,
Chia-Cheng Shih, Hung-Ming Chen
Abstract: In recent years, scaling down device dimension or utilizing novel
crystallization technologies provide the opportunity of applying much more
devices to integrated circuit fabrication. Due to emerging DSM effects, the
research about routing has drawn much attention in VLSI Physical Design. In
this paper, we will focus on three issues. One, the traditional
Manhattan routing has
longer length and larger delay than X-Architecture routing. Second, in
multilayer routing, the delay of one via is much larger than the delay of
Manhattan routing.
Third, since a routed segment and macro cell should be considered as
obstacles, we must consider the rectangle and non-rectangle obstacles, and
consider the number of vias as well. Our algorithm can handle both rectangle
obstacles and non-rectangle obstacles, and we use fewer vias and
X-Architecture router by region to construct the multilayer routing trees.
The main purpose is to obtain an obstacles-avoiding routing tree of minimal
wire length and minimal delay.
Keywords: X-Architecture,
routing, multi-layer, physical design, VLSI, algorithm
Issue 9, Volume 7,
September 2008
Title of the Paper: Analog Adaptive
Filter LMS Algorithm using CMOS 0.5 μm Technology
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Authors: Jose E. Perez-Carmona, Hector
M. Perez-Meana, Juan C. Sanchez-Garcia
Abstract: In this paper an analog adaptive filter circuit is presented, their
coefficients are adapted with analog LMS algorithm using CMOS HP 0.5um
technology. The layout simulation result shows fast convergence speed and low
power consumption. The performance in configuration as an identifier shows
that this circuit can be used in portables VLSI communications systems.
Keywords: Adaptive
filters, LMS identifier, Analog CMOS circuits, Analog building blocks, Analog
processing.
Title of the Paper: The
Sigma-Delta CNN with Second Order Noise Shaping Property
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Authors: Masatake Hirano, Hisashi
Aomori, Tsuyoshi Otake, Mamoru Tanaka
Abstract: In this paper, a novel spatial domain 2-D sigma-delta modulation
using two-layered discrete-time cellular neural networks (DT-CNNs) with
multi-stage noise shaping (MASH) property is proposed. Although the
sigmadelta modulation is widely used for realizing of analog to digital
converter (ADC), sigma-delta concepts are only for 1-D signals. Signal
processing in the digital domain is extremely useful in 2-D signals such as
image processing, medical imaging, ultrasound imaging and so on. In the proposed
architecture, the A-template is used for a digital to analog converter (DAC),
the C-template works as an integrator, and the nonlinear output function is
used for the bilevel output. Besides, due to the CNN characteristic, each
pixel of an image corresponds to the cell of CNN, and each cell is connected
spatially by the A-template. Also, the multi stage noise shaping (MUSH)
property, which is one of a very effective framework for a high order
sigma-delta modulation, is exploited for realizing a second order sigma-delta
modulator by cascade connected first-order CNN sigma-delta modulators.
Keywords: Celluler neural
network, Sigma-delta modulation, Image reconstruction, Image halftoning,
Secondorder noise shaping.
Title of the Paper: On-Condition
Maintenance of Wind Generators - from Prediction Algorithms to Hardware for
Data Acquisition and Transmission
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Authors: Inacio Fonseca, Torres
Farinha, Fernando Maciel Barbosa
Abstract: Maintenance management is a subject that, instead of reducing
importance, with the increase of equipment reliability, it increases its role
in the companies and obliges the increase of the level of demand of
professionals involved because of the new technical and environmental
demands. Sometimes, scientific developments anticipate the company’s needs
while other times it is the company that challenges science. The maintenance
area is an example that offers challenges to both science and companies in
order to optimize the performance of equipment and facilities. This is also
the case of wind generators, because their expansion, evolution, maintenance
and reliability guarantee, needs to be adequately articulated in order to
maximize production time and, obviously, to optimize maintenance
interventions. It is because of this kind of challenge that the authors are
developing new methodologies in the area of wind generators that aims to
optimize the cycles of production and, consequently, reduce other kinds of
energy production. The new features include on-line measures and the
corresponding on-time treatment, using algorithms based on time-series
forecasting and wireless technology to transmit the signals. The prediction
models uses regression techniques based on SVR, ARMA and ARIMA models,
modified according to this specific case. The weather conditions and the
technical and construction characteristics of wind generators are only some
variables that we have in account in the models that are under development.
But, if these conditions are important, it is also very important to collect,
read and treat data from sensors placed in wind generators that, because
their geographic dispersion, and difficulty of transmission, must be solved
adequately and conjugated with the above referred algorithms, in order to
implement an adequate system. This is the ambit of the present article that
reports a wide approach of a subject that usually is managed separately, this
is, the hardware from one side and the prediction algorithms from other side.
This is possible because the team has being researching and developing
algorithms and an information system, since many years ago, around the
terology subject that is a wider vision of maintenance. Then, the new methodologies,
above mentioned, will be, later, incorporated through new predictive
maintenance modules in an integrated maintenance management system called
SMIT (Terology Integrated Modular System). The base of SMIT is accessed
through a client-server system and a browser system that includes the main
modules of a traditional system, as well as a fault diagnosis module, a
non-periodic maintenance planning module and a generic oncondition
maintenance module, among other innovations.
Keywords: Maintenance management;
Predictive maintenance; Wind generators.
Title of the Paper: Automatic Design of
Optimal Logic Circuits Based on Ternary Quantum-dot Cellular Automata
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Authors: Miha Janez, Iztok Lebar Bajec,
Primoz Pecar, Andrej Jazbec, Nikolaj Zimic, Miha Mraz
Abstract: This paper treats the problems involved in the design of logic
circuits based on novel processing platform. It begins with description of
the ternary quantum-dot cell, an extended classic binary cell. These cells
are basic building blocks of quantum-dot cellular automata. They are used to
construct simple structures with inputs and output which implement some
ternary logic function. These structures are employed as building blocks of
larger and more complex circuits. The computer-aided design tool that finds
an optimal implementation of a circuit by bottom-up approach is described.
The search of a solution is based on iterative deepening. Since searching
over all possible solutions is too computationally complex, heuristics are
used to reduce the computation time.
Keywords: Quantum-dot
cellular automata, Ternary quantum-dot cell, Computer-aided design, Ternary
logic, Logic circuits, Iterative deepening, Heuristics
Title of the Paper: THAWS: Automated
Design and Deployment of Heterogeneous Wireless Sensor Networks
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Authors: Sean Harte,
Emanuel M. Popovici, Brendan O'Flynn, Cian O'Mathuna
Abstract: This research focuses on the design and implementation of a tool to
speed-up the development and deployment of heterogeneous wireless sensor
networks. The THAWS (Tyndall Heterogeneous Automated Wireless Sensors) tool
can be used to quickly create and configure application-specific sensor
networks, based on a list of application requirements and constraints. THAWS
presents the user with a choice of options, in order to gain this information
on the functionality of the network. With this information, THAWS uses code
generation techniques to create the necessary code from pre-written templates
and well-tested, optimized software modules from a library, which includes an
implementation of novel plug-and-play sensor interface. These library modules
can also be modified at the code generation stage. The application code and
necessary library modules are then automatically compiled to form binary
instruction files for each node in the network. The binary instruction files
then wirelessly propagate through the network, and reprogram the nodes. This
completes the task of targeting the wireless network towards a specific
sensing application. THAWS is an adaptable tool that works with both
homogeneous and heterogeneous networks built from wireless sensor nodes that
have been developed in the Tyndall National Institute. Its advantage over
traditional methods of WSN development is simplification of development.
Keywords: Wireless sensor
networks, Automated application development, Code generation
Title of the Paper: Analog Adaptive
Filter LMS Algorithm using CMOS 0.5 μm Technology
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Authors: Jose E. Perez-Carmona, Hector
M. Perez-Meana, Juan C. Sanchez-Garcia
Abstract: In this paper an analog adaptive filter circuit is presented, their
coefficients are adapted with analog LMS algorithm using CMOS HP 0.5um
technology. The layout simulation result shows fast convergence speed and low
power consumption. The performance in configuration as an identifier shows
that this circuit can be used in portables VLSI communications systems.
Keywords: Adaptive
filters, LMS identifier, Analog CMOS circuits, Analog building blocks, Analog
processing .
Issue 10, Volume
7, October 2008
Title of the Paper: Stability
of Driving Systems with Induction Motors. A New Method of Analysis.
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Authors: Sorin Enache, Alexandru
Bitoleanu, Monica Enache, Mircea Dobriceanu
Abstract: - This paper analyzes the stability of the driving systems with
induction motors by two methods. The first one consists in using the
geometrical locus of the roots and the second one is an original method
developed by authors. The paper details the mathematical models which are
used, the results obtained by computer simulation and the conclusions
obtained by carrying out the analysis.
Key-Words:
- Driving system, stability, static converter, induction motor, simulation.
Title of the Paper: A
2.4-GHz ISM Band Delta-Sigma Fractional-N Frequency Synthesizer with Automatic
Calibration Technique
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Authors: Shiwei Cheng, Ke Zhang,
Shengguo Cao, Xiaofang Zhou, Dian Zhou
Abstract: - In the paper, a programmable phase-locked loop (PLL) based ISM
band fractional-N frequency synthesizer, commonly used in wireless
communication system, is presented. The third order error-feedback
Delta-Sigma modulator and high linearity offset phase frequency detector
(PFD)/ Charge Pump (CP) are adopted to reduce close-in phase noise due to DS
quantization noise folding. Automatic calibration technique is also
introduced to select the optimal frequency sub-band of voltage controlled
oscillator (VCO) automatically through process, voltage and temperature (PVT)
variation. The Synthesizer is designed in UMC .18um RF process and has a die
size of 1.5mm*2.3mm. The measured phase noise is -112 dBc/Hz at 1 MHz offset.
Key-Words:
- Fractional –N Frequency Synthesizer, Delta-Sigma Modulation, Quantization
noise folding, Automatic Calibration Technique.
Title of the Paper:
Current Decomposition Methods Based on p-q and CPC Theories for Active
Filtering Reasons
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Authors:
Alexandru Bitoleanu, Mihaela Popescu, Mircea
Dobriceanu, Felicia Nastasoiu
Abstract:
- This paper presents a comparative analysis of three current decomposition
methods in three-phase systems without neutral wire on the basis of some case
studies. The analysis takes into consideration the Currents’ Physical
Components (CPC) introduced by Professor Czarnecki in 1988 [1], the active
and the reactive components of the p-q theory of the instantaneous power
introduced by Professor Akagi and his coauthors in 1983 [2] and a modified
variant of the Akagi’s components proposed by the authors for the operation
under unbalanced or nonsinusoidal conditions [3]. We propose four components
of the current space-vector in terms of DC and AC components of the
instantaneous active and reactive powers. The term of supplementary useless
current vector is also pointed out. The analysis shows that the current
decomposition which respects the definition of the instantaneous apparent
power vector is useful for compensation reasons only if the supply voltages
are sinusoidal. A modified definition of the components of the current is
proposed for the operation under no sinusoidal voltage conditions. This case
studies based-analysis allows finding again some deficiencies that Professor
Czarnecki has pointed out relating to Akagi’s current decomposition [4], [5].
It is shown that the proposed active and reactive current components are
identical to those of Czarnecki’s CPC theory.
Key-Words:
- Active current, Reactive current, Unless current, Unbalanced load,
Nonsinusoidal conditions.
Title of the Paper:
Design and Implementation of a Chassis Dynamometer for Testing Battery-Powered
Motorcycles
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Authors:
Ding-Tsair Su, Ying-Shing Shiao, Jui-Liang
Yang
Abstract:
- The objective of this paper is to design and implement a chassis
dynamometer for testing dynamic characteristics of a battery-powered
motorcycle (BPM). By using a load simulation system, which is constituted
with a DC motor and two rollers, a roller of the test platform is connected
to a DC motor through a torque sensor, and a controller is designed to
control the DC motor to simulate driving resistance produced when the BPM
runs on various roads. The test platform can simulate each drag force when
the BPM is in acceleration or in a constant-speed drive, and also can
simulate kinetic energy gained by the BPM when braking, deceleration and
running downhill. A computer not only controls the test platform but also
collects signals from sensors on the test platform and the BPM, and can
analyze related data such as driving resistance, driving range, speed,
kinetic energy recycle and so on. The test platform has an integral steel
structure and a stable center of gravity, and the height and length
adjustment of the machine is convenient and as well the test is easy to
perform, thus it can provide efficient tests on battery-powered motorcycles
(BPMs) which are currently popularized by all circles with great efforts, so
as to achieve the objective of performance measurement, performance analysis
and data collection. From experiment results, the BPM performance test
platform can simulate various road patterns and complete an automatic testing
process.
Key-Words:
- Chassis dynamometer, Battery-powered motorcycle, Test platform, Driving
resistance, Drag force, Kinetic energy recycle, Road patterns.
Title of the Paper: Design
of a Fast, High Power Magnetic Generator for the Stimulation of Living
Tissues: A Biomedical Engineering Application of Electromagnetism and Power
Electronics
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Authors:
R. Charlet De Sauvag, Ph. Dondon, C. Martin,
J. Donkin , B. Veyret
Abstract:
This paper relates to the design and realization of a high power (6000 A, 650 V) magnetic
generator delivering ultra short (340 μs) high intensity (2 T) pulses.
More than ten years of technical collaboration between two important graduate
engineering schools of Bordeaux
were necessary to carry out this project. This practical realization was
supported perfectly by the power electronics, electromagnetism and
microprocessor courses given at ENSCPB and ENSEIRB graduate engineering
schools. In the first place, we explain the educational interests of this
realization. Then, we give a detailed description of the system, including
the tests which were used to check the specifications. Finally we conclude on
possible uses of our equipment in biomedical research. As an illustration of
bio medical applications, our apparatus was used for tests on living tissues
(animal, bacteria, etc).
Key
words: Magnetic stimulation, Living tissues, Biological tests, Power
electronics, Electromagnetism.
Title of the Paper: A
Comparative Study of Simple Online Learning Strategies for Streaming Data
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Authors: M. Millan-Giraldo, J. S.
Sanchez
Abstract:
Since several years ago, the analysis of data streams has attracted
considerably the attention in various research fields, such as databases
systems and data mining. The continuous increase in volume of data and the
high speed that they arrive to the systems challenge the computing systems to
store, process and transmit. Furthermore, it has caused the development of
new online learning strategies capable to predict the behavior of the
streaming data. This paper compares three very simple learning methods
applied to static data streams when we use the 1-Nearest Neighbor classifier,
a linear discriminate, a quadratic classifier, a decision tree, and the
Na¨ıve Bayes classifier. The three strategies have been taken from the
literature. One of them includes a time-weighted strategy to remove obsolete
objects from the reference set. The experiments were carried out on twelve
real data sets. The aim of this experimental study is to establish the most
suitable online learning model according to the performance of each
classifier.
Key–Words:
Data mining, Online learning, Static streaming data, Forgetting.
Title of the Paper: REI
Equivalent Design for Electric Power Systems with Genetic Algorithms
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Authors: Mihai
Gavrilas, Ovidiu Ivanov, Gilda Gavrilas
Abstract:
- Present day power systems are often large or very large systems, with a
high degree of interconnectivity. Their analysis can be simplified using
network equivalents, which decrease the size of the system by replacing a
significant part of it with only a few nodes. The chosen equivalent is the
REI equivalent. This paper describes a new approach to the problem of the REI
equivalent design optimization, based on the sensitivity of the complex bus
voltage from the internal unmodified section of the power system to a set of
simulated representative contingencies. The optimal equivalents are
determined using artificial intelligence techniques, namely genetic
algorithms. The optimum design of the REI equivalent aimed to determine the
number of REI buses to be used and the aggregation of external buses into the
REI buses. The method was tested on a slightly modified version of the IEEE
57 bus test system. The obtained results prove the efficiency of the proposed
method.
Key-Words:
- Static network equivalents, REI equivalent, Load flow analysis,
Contingency, Genetic algorithms, Sensitivity analysis.
Issue 11, Volume
7, November 2008
Title of the Paper: Device
and Memory Array Models for Flash EEPROM Technology
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Authors: Hassen
Aziza, Bertrand Delsuc
Abstract: - In this paper, three EEPROM memory cell models are presented. The
first model is a compact model based on Mos Model 11 (MM11) and fully
validated on silicon. From this first model we propose two alternative models
(level 1 & level 2). These last models allow a reduction of simulation
time and memory space overheads, with respect of accuracy, compared to the
original compact model. The technique used to build the level 1 and level 2
models is based on the complexity reduction of the original EEPROM model. We also
present simulation time results using the different models within memory
arrays.
Key-Words:
- EEPROM, Modeling, Memory arrays, Simulation time.
Title of the Paper: Sensor
Data Acquisition for Climate Change Modelling
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Authors: Subana
Shanmuganthan, Akbar Ghobakhlou, Philip Sallis
Abstract: - This paper describes recent advances in sensor technology and
wireless radio frequency (telemetry architecture) with the capability for
measuring changes in weather and atmospheric conditions that permit modellers
to analyse the climate change, its variability and effects on viticulture
across the world’s major wine producing regions. When combined with GPS (global
positioning system) functionality enabling geo-referenced information to be
gathered and analysed in real-time, new opportunities emerge for the
development of wireless sensor networks (WSN) for decision making in
precision agriculture (PA). The use of WSN technologies in precision
viticulture (PV) to date is mostly confined to on-farm and narrow regions
within a city or in the case of a larger region the data collection is
limited to monitoring weather conditions alone. This paper reviews three
application scenarios: a) within a vineyard b) regionally within the state of
Washington in the USA and c) cities within the Asia
Pacific Region. It then details the development of a system proposed for
comparative analysis of viticulture management information from two countries,
namely Chile and New Zealand
that have the same latitude but are at different longitude points. The paper
looks at a variety of remotely located real-time sensors (telemetry devices),
associated hardware devices (server, workstation, architectures and
topologies) and software suitable for data collection, logging, distribution
and streaming. Data gathered by the sensors is relayed via a series of
repeaters to a workstation, which logs the data and is connected directly to
the Internet for transmission to a server acting as the final collection and
data analysis point for a comparative information matching synthesis. The data
collected is to be used for building models that could enhance our
understanding about the effects of climate change on grapevine growth and
wine quality within major wine regions in the two countries being studied in
this initial research. Finally, the paper describes variable parameters
considered for analysis in this research so far in relation to plant growth, weather,
climate, atmospheric influences such as climate change, pollution and also
wine quality determinants such as soil, terrain and grape variety.
Key-Words:
- Telemetry devices, plant growth factors, weather data, GPS and precision
viticulture.
Title of the Paper: Automatic
Placement of Micropipeline Standard Cells
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Authors: Alaaeldin Amin
Abstract: - A new algorithm for automated standard cell placement of
asynchronous Micropipeline designs has been developed. The resulting
placement solutions are targeted to meet all bundled-data timing constraints while
providing efficient chip areas. The placement algorithm utilizes the
simulated evolution iterative heuristic. The cost function is a weighted sum
of an area factor and a timing factor. Results of five experimental circuits
show that full routability with reasonably efficient areas are possible.
Key-Words:
- Asynchronous systems; Micropipelnes; Automatic placement and routing; Stochastic
Evolution.
Title of the Paper: Design
and Implementation of a New Permanent Magnet AC Contactor with Colenoid
Actuator
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Authors: Chieh-Tsung
Chi
Abstract: - This paper focuses on presenting a new permanent magnet with
colenoid actuator for the purpose of reducing the energy dissipation during a
complete operation. The methodology developed is a hardware based approach. It
emphasizes on minimizing the cost of operation over a specified time period
rather than a fixed operating point. The practical operating concerns of
proposed ac permanent magnet (PM) contactor and the coordination with a new
actuator are also addressed. The developed ac PM contactor has been
implemented as a prototype grade product. Test results on the experimental prototype
and computer simulation model show that the energy-saving performance of this
newly developed ac PM contactor is effective and feasible.
Keywords:
- AC PM contactor, permanent magnet, energy saving, simulation model, experimental
prototype, actuator..
Title of the Paper: The
Efficient TAM Design for Core-Based SOCs Testing
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Authors: Jiann-Chyi Rau, Po-Han Wu, Chih-Lung
Chien, Chien-Hsu Wu
Abstract: - This paper presents a framework and an efficient method to
determine SOC test schedules. We increase the test TAM widths by the framework.
Our method deals with the traditional scan chains and reconfigurable multiple
scan chains. Experimental results for ITC’02 SOC TEST Benchmarks show that we
obtain better test application time when compared to previously published
algorithms. Test access mechanism (TAM) and test schedule for System-On-chip (SOC)
are challenging problems. Test schedule must be effective to minimize testing
time, under the constraint of test resources. This paper presents a core
section method based on generalized 2-D rectangle packing. A core cuts into
many pieces and utilizes the design of reconfigurable core wrappers, and is
dynamic to change the width of the TAM executing the core test. Therefore, a
core can utilize different TAM width to complete test.
Keywords:
- SOC Testing, TAM, Testing Scheduling.
Issue 12, Volume
7, December 2008
Title of the Paper: Path
Tracking Laws and Implementation of a Vision-Based Wheeled Mobile Robot
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Authors: Ying-Shing Shiao, Jui-Liang
Yang, Ding-Tsair Su
Abstract: This paper has studied techniques for building system configuration,
control architecture and implementation of a vision-based wheeled mobile
robot. The completed WMR has been built with the dead-reckoning method so as
to determine the vehicle’s velocity and posture by the numerical
differentiation/integration over short travelling. The developed PID
controllers show good transient performances, that is, velocity of right and
left wheels can track the commands quickly and correctly. Moreover, the path
tracking control laws have been also executed in the DSP-based controller in
the WMR. The image-recognized system can obtain motion information 15
[frames/sec] by using H-S model, which is one of the well -known color
detection methods. The better performance a vision system has, the more
successful the control laws design. The WMR obtains its posture from the
deadreckoning device together with the vision system. Finally, we integrate
these subsystems and complete the operators of the whole system. This
complementing wheeled mobile robot system can be thought of as a platform for
testing various tracking control laws and signal filtering method. To solve
the problem of position/orientation tracking control of the WMR, two
kinematical optimal nonlinear predictive control laws are developed to
manipulate the vehicle to asymptotically follow the desired trajecto ries. A
Kalman filtering scheme is used to reduce the bad effect of the imagine nose,
thereby improving the accuracy of pose estimation. The experimental system is
composed of a wireless RS232 modem, a DSP -based controller for the wheeled
mobile robot and a vision system with a host computer. A computation
-effective and highperformance DSP-based controller is constructed for
executing the developed sophisticated path tracking laws. Simulation and
experimental results are included to illustrate the feasibil ity and
effectiveness of the proposed control laws.
Keywords: Predictive control, Mobile robot, Path tracking, Nonlinear
characteristics, Kalman filtering
Title of the Paper:
Evaluation Method of the Sensors Errors in an Inertial Navigation System
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Authors: Teodor Lucian Grigorie, Nicolae
Jula, Costin Cepisca, Ciprian Racuciu, Dan Raducanu
Abstract: The subject of this paper is a study of the influence of the
inertial sensors errors on the position, speed and attitude of a bidimensional
strap-down inertial navigation system in a horizontal plane. The MATLAB/SIMULINK
models used for the acceleration and rotation sensors are based on the sensors
data sheets and on the IEEE equivalent models for the inertial sensors. The
models can be used in the numerical simulation of the strap-down inertial
navigation system, close by real conditions from the point of view of the
distortions suffered by the useful acceleration and rotation signals at the
passing through any type of accelerometers or gyros desired to be implemented
in the navigator. These models have the advantage to work independent from
each of the sensors’ errors and thus to study their influence on the inertial
navigator.
Keywords: Sensors Models, Positioning Errors, Inertial Navigator, Inertial
Sensors, Strap-Down
Title of the Paper:
Performance Analysis of High Speed Power Quality Disturbance Recognition
Scheme for Static Transfer Switch Application
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Authors: Ramesh Pachar, Harpal Tiwari,
Ramesh C. Bansal
Abstract: The static Transfer Switch (STS) is a network reconfiguring device
and is used for power quality improvement of sensitive loads. It selects, at
high speeds, between two or more sources of power and provides the best
available power to the sensitive load. This paper presents fundamentals of
solid state STS with a detailed emphasis on power quality disturbance
recognition scheme, as it is responsible for fast and accurate detection of
disturbances, thereby ensuring healthy transfer of load to an alternate
source. Extensive simulations are carried out for investigating the
performance of rather commonly employed detection scheme. The behavior of
detection scheme is analyzed against various types of disturbance scenarios
including system transients.
Keywords: Power Quality, Static Transfer Switch, Detection Scheme, Transfer
Time, Sensitive Loads, Custom Power Devices
Title of the Paper:
Theoretical and Practical Aspects for Study and Optimization of the Aircrafts'
Electro Energetic Systems
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Authors: Nicolae Jula, Costin Cepisca,
Lungu Mihai, Ciprian Racuciu, Tudor Ursu, Dan Raducanu
Abstract: The paper presents a concrete case of an actual aircraft electric
power system analysis. Using the Boolean logical structures we define a
conceptual fault tree. The fault tree will express all the combination of
factors that can lead to system failure in the onboard electric system. The
further on analysis rely on AND – OR logic elements, and the goal is to
improve the fault-tolerance behavior of the system. The examples and numeric
figures are for a c.c. electric power system of an operational aircraft.
Keywords: Reliability analysis, Boolean logic, aircraft, electric power,
energetic system
Title of the Paper:
Chaos-Low Periodic Orbits Transition in a Synchronous Switched Circuit
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Authors: N. Jabli, H. Khammari, M. F.
Mimouni
Abstract: In this paper we consider a modified model of an Alpazur oscillator
with a periodically switching operation. Complex oscillatory phenomena are
observed due to both switching operation and the appearance of an additional
nonlinear component in circuit model. Indeed, subharmonic oscillations and
chaotic behavior are illustrated. In addition, time series, phase trajectories
and power spectrum was examined in the analysis of the system dynamics. The
transition to chaotic states through doubling period bifurcation cascade and
the direct transition from fundamental harmonic or odd subharmonic orbits and
transition from a special bifurcation paths to chaotic states are discussed in
the state space. The role of higher harmonic spectral lines in period-1
responses under parameter variation have seemingly similarities with the
results obtained in previous works for non switched dynamical system. Chaotic
states resulting from different transition modes are also presented in this
paper. For the numerical simulations, techniques for deriving time and
composite Poincare method are applied.
Keywords: Switching operation,Transition modes, higher harmonic predominance,
doubling period cascade
Title of the Paper:
Household Type Load's Effects on Photovoltaic Systems
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Authors: Nazmi Ekren, Nevzat Onat, Safak
Saglam
Abstract: The solar energy is one of the most important energy sources
available because, besides the fact that it is not polluting the environment
and it helps to the reduction of green house effect, it is free of charge and
it can be easily converted to other forms of energy. Clean and renewable
energy production is getting more attractive due to global warming,
environmental factors and decrease in conventional energy sources.
Photovoltaic cells will be a good alternative against the conventional energy
sources in the near future, with their decreasing costs and increasing
efficiencies. Photovoltaic cells (PV) are exposed to a lot of various loads
depending on their increasing usage areas. Among the energy expenses for a
building, the lighting system can contribute up to 50% of the total electrical
consumption, and especially large quantities of energy are used in schools and
office buildings. For that reason lighting devices are important energy
consuming units in our daily life. In this study different load effects on PV
cells are examined experimentally. D.C. and A.C. load behaviors are analyzed
in switching and in steady state regime and their power-time curves are
obtained for the demand of system power. Negative effects of the inverter
circuit, which is used for feeding A.C. loads on the system, are expressed
experimentally.
Keywords: Photovoltaic System, A.C. Loads, D.C. Loads, Power LED, Compact
Fluorescent Lamp
Title of the Paper: The
Application of Compound Neural Network in Condition Estimate of Power
Transformer
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Authors: Zhang Weizheng, Wang Zhenggang,
Fu Yingshuan, Liu Fazhan, Yang Lanjun, Li Yanming
Abstract: The analyses of light gases in transformer oil provide the basis of
a diagnostic evaluation of equipment health. Two new normalized methods which
named characteristic normalization and mix normalization are presented in this
paper. The Fisher rule to evaluate the results of the two pretreatment methods
is also introduced. The evaluation of the results indicates that both of the
two data pretreatment methods can achieve the purpose of big difference in the
value of mean between classes and small difference in dispersion of a class.
The DGA data of the failure transformers are treated by different
normalization methods as the training samples, and then the samples are
trained in the compound neural networks which use the CP algorithm. The
diagnosis results of the test samples indicate that the new methods may help
to improve the precision of network diagnosis.
Keywords: Transformer, analysis of reliability data, CP compound neural
networks, condition estimate
Title of the Paper: NIRE:
A New Approach in Obtaining Transfer Functions for a Linear Network
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Authors: F. R. M. Rashidi, R. M. T. R.
Ismail, R. Ishak
Abstract: Nowadays, there are lots of classic and alternative method that has
been used to obtain and compute transfer function for a linear network.
Although, problems still occur especially in the number of nodes, loops and
simultaneous equations that need to be solved by this approaches. A proposed
approach called NIRE (Network-Impedance Relationship Equation) will solve
these problems by developing fixed equations for obtaining transfer function,
rather than to extract its nodes, loops or simultaneous equations of its
network. In this approach, the only required parameters are the network’s
impedance connections which will be taken from two sources which are from the
input terminal and output impedance. The approach has been developed in an
algorithm using software called MATLAB. It can be adapted in a computer-based
application and also can be introduced as an alternative method in obtaining
transfer function for educational purpose.
Keywords: Transfer function, impedance, circuit, large-scale, linear, symbolic
circuit analysis
Title of the Paper:
Transition Faults Detection in Bit Parallel Multipliers over GF(2m)
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Authors: Hafizur
Rahaman, Jimson Mathew, Ashutosh K. Singh, Dhiraj K. Pradhan, Biplab K. Sikdar
Abstract: In this article, a C-testable design for detecting transition faults
in the polynomial basis (PB) bit parallel (BP) multiplier circuits over GF(2m)
is discussed. For 100 percent transition fault coverage, the proposed
technique requires only 10 vectors, irrespective of multiplier size, at the
cost of 6 percent extra hardware. The proposed constant test vectors which are
sufficient to detect both the transition and stuck-at faults in the multiplier
circuits can be derived directly without any requirement of an ATPG tool. As
the GF(2m) multipliers have found critical applications in public key
cryptography and need secure internal testing, a Built-in Self-Test (BIST)
circuit may be used for generating test patterns internally. This will obviate
the need of having three extra pins for the control inputs and also provides
public-key security in cryptography. Area and delay of the testable circuit
are analyzed using SynopsysO tools with 0.18m CMOS technology library from UMC.
Keywords: Transition fault, Galois field, multiplier, cryptography, error
control code, VLSI testing
Title of the Paper: DSP
Based On-line Partial Discharge Monitoring System for High Voltage Power Cable
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Authors: Canxin Guo, Yong Qian, Chengjun
Huang, Linpeng Yao, Xiuchen Jiang
Abstract: In high voltage power cable system, partial discharge (PD) is a
common phenomenon which reflects the degradation of insulation. When partial
discharge happens inside the cable, leakage current will flow through the
grounded conductor. To couple the partial discharge current, one feasible and
effective method is placing a clamp-on high frequency current transformer
around the grounded strap. In order to precisely monitor the insulation
degradation, a digital signal processor (DSP) based partial discharge on-line
monitoring system is developed and presented in this paper. The system mainly
consists of PD sensor, pre-amplifier, front-end sample device and remote
server center. The front-end device is the kernel part of the system, as it
performs PD signals sampling and some essential digital signal processing such
as noise filtering, pulse extraction and parameters statistics. Then, the
derived characteristic parameters are sent to the remote server center by
ethernet communication for further analysis. The field test and data analysis
show the presented system is effective and helpful for power cable condition
diagnosis.
Keywords: High voltage, Power cable, Partial discharge, DSP, On-line
monitoring, Signal Processing, Ethernet communication
Title of the Paper:
Current Conveyor-Based Versatile Precision Rectifier
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Authors: Montree Kumngern, Kobchai
Dejhan
Abstract: A versatile precision rectifier based on a current conveyor and
current mirrors is presented. The proposed circuit performs positive
half-wave, negative half-wave, positive full-wave, and negative full-wave
rectification into a single circuit. The current-mode technique has been
employed to provide the high-precision capability of the circuit. The circuit
configuration is very suitable for integrated circuit implementation both in
bipolar and CMOS technologies and it exhibits a precise rectifier and good
temperature stability. Simulation results using the PSPICE program based on
0.5?m CMOS parameter through MIETEC demonstrate the performance of the
proposed rectifier. Experimental results are provided to confirm the theory.
Keywords: Precision rectifier, current conveyor, current-mode, half-wave,
full-wave
Title of the Paper: Wu
Elimination Method Applied in Static Analysis of the Power System
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Authors: Qing Zhang, Chen Chen
Abstract: Wu Elimination Method is applied to obtain analytical solution of
power flow equations without either extraneous roots or missing roots. The
symbolic process of Wu Elimination is implemented by software MAPLE. A minor
group of solutions is obtained under low load other than the major group of
solutions. Based on computation, analytical , curves as well as the steady
state operation area. The results are compared with the results of Homotopy
Method. Discussion on unstable equilibrium points is presented which is
potentially valuable for research on voltage stability and angle stability of
complex power systems.
Keywords: Wu Elimination Method, Power system, curve, Voltage stability, Angle
stability
Title of the Paper: A
New Classification Pattern Recognition Methodology for Power System Typical
Load Profiles
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Authors: G. J. Tsekouras, F. D. Kanellos,
V. T. Kontargyri, I. S. Karanasiou, A. D. Salis, N. E. Mastorakis
Abstract: In this paper a new pattern recognition methodology is described for
the classification of the daily chronological load curves of power systems, in
order to estimate their respective representative daily load profiles, which
can be mainly used for load forecasting and feasibility studies of demand side
management programs. It is based on pattern recognition methods, such as
k-means, adaptive vector quantization, self-organized maps (SOM), fuzzy
k-means and hierarchical clustering, which are theoretically described and
properly adapted. The parameters of each clustering method are properly
selected by an optimization process, which is separately applied for each one
of six adequacy measures: the error function, the mean index adequacy, the
clustering dispersion indicator, the similarity matrix indicator, the Davies-Bouldin
indicator and the ratio of within cluster sum of squares to between cluster
variation. This methodology is applied for the Greek power system, from which
is proved that the separation between work days and non-work days for each
season is not descriptive enough.
Keywords: Load profiles, clustering algorithms, adaptive vector quantization,
fuzzy k-means, hierarchical clustering, k-means, self-organized maps, pattern
recognition, adequacy measures
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