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Issue 1, Volume 9,
January 2010
Title of the Paper: Quantum-Well
Tridiagonal: A Qualitative Comprehension of Optoelectronics Nanotechnology
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Authors:
E. A. Anagnostakis
Abstract: A simple effective algorithm (“QUANTUM-WELL TRIDIAGONAL”) for
studying the essential features, causalities, and applicabilities of an
optoelectronics nanoheterointerfacial generic quantum well (QW) is outlined in
terms of transforming the pertinent initial Schroedinger equation into a
normalised Sturm – Liouville one and, ultimately, into an eigensystem
concerning a specific tridiagonal matrix. A qualitative comprehension of
optoelectronics nanotechnology basics is, thus, envisaged to be offered.
Keywords: Quantum-well
tridiagonal, optoelectronics, nanoheterointerfacial, quantum well,
schroedinger equation, sturm – liouville equation, nanotechnology
Title of the Paper: Performances of
CMOS Thermal-Compensation Total-Current References
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Authors:
Radu D. Mihaescu, Mircea A. Ciugudean
Abstract: "Total"-current reference sources, composed of two classic
cross-connected current mirrors, have been launched by the authors in some
earlier published works. Theirs major advantages are: simple serially
interconnection with the charge and the minimum supply current (this is just
the reference current). This work is a comparative analysis of the
performances of two total-current reference-source variants with first and
second-order thermal compensation, using different integrated resistor types,
having positive, zero or negative temperature coefficient. The possibility of
obtaining a set of good performances by using NTC resistors is signalled but
also, the inefficiency of second-order thermal-compensation for many cases of
resistor- temperature-coefficient combinations. A total temperature variation
of the reference current, for a particular source variant, is reported, which
represents a record: 0.017% for a temperature range of 0-100oC.
Keywords: Analogue
Integrated Circuits, CMOS Current Reference, Thermal Compensation,
Total-Current Reference
Title of the Paper: Simulation the
Functionality of a Laser Pulse Image Acquisition System
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Authors:
Toadere Florin, Nikos E. Mastorakis
Abstract: The goal of this paper is to generate a laser pulse and to capture
it by an image acquisition system. We use a confocal resonator to generate a
laser pulse; then the generate light is focused in to an optical fiber using a
lens; the light propagates through the fiber and at the fiber output light is
projected on a CMOS sensor. We compute the PSF (point spread function) and MTF
(modulation transfer function) in order to characterize the functionality of
the lens and the optical part of a CMOS sensor. We analyze the CMOS electrical
part considering the photon shot noise and the FPN (fixed pattern noise).
Finally, we use a Lapacian filter, an amplitude filter and a bilateral filter
in order to reconstruct the noisy blurred image. We consider the image capture
system to be linear shift invariant, axial and the light is orthogonal to the
system.
Keywords: Hermite Gaussian
polynomial, lens design, PSF, MTF, fixed pattern noise, photon shot noise,
amplitude filter, Laplacian filter, bilateral filter
Title of the Paper: An Overview about
Monitors Colors Rendering
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Authors:
Toadere Florin, Nikos E. Mastorakis
Abstract: The goal of this paper is to study how different TV technologies
work, and to compare them. We analyze three different situations: a CRT
monitor, a LCD monitor and a LEDs monitor. Using the different monitors’
spectral power distributions, we propose a six steps spectral image processing
algorithm which converts the spectral image in to XYZ standard and then in to
the RGB standard. Finally we colour balance the RGB image in order to
eliminate the monitors unwanted render colours hues. On the monitors displays
we expect to see the same colours text image. Also we present the monitor’s
colours properties like: colours saturation, brightness, contrast and sharp.
Keywords: Spectral image,
CRT, LCD, LED monitors, monitors spectral power distribution, render image
colors properties
Title of the Paper: A Novel Design for
Evaluating Simultaneous Switching Noise within an Enhanced IBIS Model
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Authors:
Wen-Tzeng Huang, Sun-Yen Tan, Yuan-Jen Chang, Chiu-Ching Tuan
Abstract: Simultaneous switching noise (SSN) is a major cause of power
integrity (PI) degradation that causes circuits to become unstable and
experience errors. As modern ICs operate at higher speeds with higher density
and lower voltages, SSN has become a serious issue that must be addressed to
ensure system stability during the short rise- and fall-times of the logic
transient states. Most traditional designs have generally used decoupling
capacitors to reduce SSN. As these capacitors become equivalent series
inductances when the system operates at high frequencies, such a technique
works against reducing SSN. Therefore, we propose a methodology called the
enhanced IBIS model that effectively alleviates the problem of SSN using an
evaluation based on the enhanced I/O buffer information specification (IBIS)
model with decoupling capacitors and a high-frequency low-impendence circuit.
In this study, we showed that SSN from 452 mV, 290 mV, 163 mV, and 301 mV, of
IBIS, traditional decoupling capacitors, IBIS with a high-frequency
low-impendence circuit, and HP Simulation Program with Integrated Circuit
Emphasis (HSPICE) methodologies, respectively, was effectively reduced by 121
mV of our enhanced IBIS mode as measured by the peak-to-peak value. That is,
our new method reduces noise by more than 73.2%, 58.3%, 25.7%, and 59.8%
compared to other four methodologies, respectively.
Keywords: Simultaneous
Switching Noise (SSN), Power Integrity (PI), I/O Buffer Information
Specification (IBIS), HSPICE, High-frequency low-impedance (HFLI) circuit
Title of the Paper: Design and
Implementation of a Negative Feedback Oscillator Circuit Based on a Cellular
Neural Network with an Opposite Sign Template
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Authors:
Baran Tander, Atilla Ozmen, Yasin Ozcelep
Abstract: In this paper, explicit amplitude and frequency expressions for a
Cellular Neural Network with an Opposite-Sign Template (CNN-OST) under
oscillation condition are derived and a novel inductorless oscillator circuit
with negative feedbacks, based on this simple structure is designed and
implemented. The system is capable of generating quasi-sine signals with
tuneable amplitude and frequency which can’t be provided at the same time in
the classical oscillator circuits.
Keywords: Oscillator
Circuits, Cellular Neural Networks, Quasi-Sine Signals, Curve and Surface
Fitting, Operational Amplifiers, Circuit Design
Issue 2, Volume 9,
February 2010
Title of the Paper: Automated Traffic
Light System for Road User's Safety in Two Lane Road Construction Sites
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Authors:
Siva Kumar Subramaniam, Vigneswara Rao Ganapathy, Sivarao Subramonian, Abdul
Hamid Hamidon
Abstract: The road construction safety traffic light system is designed to
replace a manual traffic control on a road construction sites. This device can
replace one or both flaggers during the two lane closures on the event of a
road construction. The road construction safety traffic light system is
considered one of the best devices in work zone traffic flow control systems.
The device is a portable traffic light unit which can be best utilized in
controlling traffic flow in a road construction site for long term or short
term lane closures and to control two-way traffic in a single lane. By
implementating new technologies in automating traffic flow in road
construction site could possibly eliminate the usage of a conventional flagman
at all times. The road construction safety traffic light system is a practical
solution to solve problems which contribute towards hazards at road
construction site and to be inline with the road safety regulation which is
taken into granted by the contractors. The automated portable traffic light
system can reduce direct costs in man power utilization and increase safety
for the road users and construction workers by eliminating the need for a
human flagmen. This system is applicable for public and privately funded road
construction projects that require overnight or 24-hour traffic control as
well as in different weather conditions.
Keywords: Intelligent
traffic light system, programmable logic controller, smart control
application, flagman, traffic light
Title of the Paper: State-Space
Averaging (SSA) Revisited: On the Accuracy of SSA-Based Line-To-Output
Frequency Responses of Switched DC-DC Converters
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Authors:
Viera Biolkova, Zdenek Kolka, Dalibor Biolek
Abstract: The line-to-output (LTO) frequency response of switched DC-DC
converter describes how the smallsignal harmonic perturbation of the converted
input DC voltage penetrates into the converter output, depending on the
frequency of this perturbation. In the paper, the LTO frequency response
conceived in this sense is faced with the LTO response, obtained by applying
the well-known State-Space-Averaging (SSA) technique to switched converters,
with the aim of determining the fundamental limitations of the SSA-approach.
The general analysis is then applied to Buck-, Boost-, Buck-Boost-, and Cuk-
type converters. It is shown that the accuracy of SSA outputs is related to
the character of the state matrices of the converters.
Keywords: Switched DC-DC
converter, averaging, SSA, spectrum, LTO frequency response
Title of the Paper: Comparative Study
of Noise Reduction in Ultrasonic Inspection System
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Authors:
Jaejoon Kim
Abstract: The effective noise reduction schemes in ultrasonic inspection have
shown significant role for detection of flaws in materials. This paper
presents the comparative result of noise reducing schemes based on
Hilbert-Huang transform and Wavelet transform. The basic principle of HHT
scheme includes two parts which are empirical mode decomposition (EMD)
algorithm and a sum of intrinsic mode functions (IMF). By doing EMD process,
the valuable information out of individual IMF can be maintained with reduced
noise level for feature vectors. In the Wavelet transform, the signals are
decomposed into low and high information and the feature vectors can be
selected by Wavelet coefficients. In order to compare the performance of the
two distinct schemes, this paper utilizes the soft and hard thresholding
criterion on WT and HHT.
Keywords: Ultrasonic
inspection, Automatic signal processing, Hilbert-Huang Transform, Wavelet
Transform, Denoising scheme, Nondestructive evaluation
Title of the Paper: Evaluating
Multicast Resilience in Carrier Ethernet
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Authors:
Sarah Ruepp, Henrik Wessing, Jiang Zhang, Anna V. Manolova, Anders Rasmussen,
Lars Dittmann, Michael Berger
Abstract: This paper gives an overview of the Carrier Ethernet technology with
specific focus on resilience. In particular, we show how multicast traffic,
which is essential for IPTV can be protected. We detail the background for
resilience mechanisms and their control and we present Carrier Ethernet
resilience methods for linear and ring networks. By simulation we show that
the availability of a multicast connection can be significantly increased by
applying protection methods.
Keywords: Carrier
Ethernet, Resilience, IPTV, Simulation, Protection, OAM
Title of the Paper: Evaluation of
Dynamic Bandwidth Allocation Algorithms in GPON Networks
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Authors:
Joanna Ozimkiewicz, Sarah Ruepp, Lars Dittmann, Henrik Wessing, Sylvia Smolorz
Abstract: In this paper, two approaches for Dynamic Bandwidth Allocation in
GPON networks are proposed, and validated through simulations in the OPNET
modeler. One approach address a Status Reporting scheme, where the bandwidth
allocation originates from the client request. The second use a centralized
Non Status Reporting scheme. Furthermore, parameters to cope with variances in
the traffic pattern is quantified. The results on performance, scalability and
efficiency show that Status Reporting is utilizing the bandwidth more
efficient while the Non Status Reporting provides better QoS for real time
services.
Keywords: GPON, dynamic
bandwidth allocation (DBA), simulation, status reporting, OPNET
Title of the Paper: Testing of High
Breaking Capacity Fuses Using Modular Current Sources
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Authors:
Adrian Plesca, Emilian Furnica
Abstract: There are many types of switching and protection electrical
apparatus used in different power systems with the goal to supply at adequate
parameters industrial or domestic consumers. The time-current characteristics
of the protection electrical apparatus from datasheets have accuracy up to ±
30%. Hence, in order to achieve a safe protection at overcurrents it is
necessary to test the electrical apparatus using proper devices. Therefore,
the aim of this paper is to present new types of modular current sources and
some possibilities to adjust their parameters. Then, a method to obtain the
time-current characteristics of low voltage high breaking capacity fuses
without fusing is presented.
Keywords: Modular current
source, testing, method, high breaking capacity fuse
Issue 3, Volume 9,
March 2010
Title of the Paper: Nanometric Layers
of Cadmium Sulphide by CBD and a Potential Application
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Authors:
M. C. Acosta-Enriquez, A. Apolinar-Iribe, M. E. Alvarez-Ramos, M. A. Quevedo-Lopez,
R. Ramirez-Bon, A. F. Jalbout, A. De Leon, A. Duartemoller, R. P. Duarte-Zamorano,
L. E. Regalado, M. R. Manzo-Valencia, S. J. Castillo
Abstract: We presented an application of nanometric layers of Cadmium Sulphide
developed using Chemical Bath Deposition (CBD) technique for the growth of the
CdS thin films. The thin films of CdS were synthesized employing two different
complexing agent, acetilacetone and glycine. In this paper we compare the
results of the thin films characterization with both complexing agent and the
CdS thin film growth with glycine was selected in order to develop a Thin Film
Transistor (TFT). The energy bandgaps in these cases were Eg = 2.53 eV using
glycine as complexig agent, and Eg= 2.37eV using acetylacetone as complexing
agent. An hexagonal polycrystalline structure concerning to the X-ray analysis
results for both processes, from those studies were calculated their grain
sizes by the model of Debye-Scherrer, resulting 3 nm for the acetylacetone
process and 30 nm for the glycine process. Also we started with the
computational analysis and preliminary results are presented.
Keywords: Cadmium Sulfide,
Semiconductors, Thin Films, Acetylacetone, Glycine and Transistors
Title of the Paper: Formation of ZnO in
or on Glasses by Using the Sol-Gel and Chemical Bath Deposition Techniques
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Authors:
S. J. Castillo, M. C. Acosta-Enriquez, Ma. E. Zayas, H. Arizpe, T.
Mendivil-Reynoso, A. Garcia-Juarez, M. E. Alvarez-Ramos, E. Larios-Rodriguez
Abstract: In the first part of this work was produced Zinc Oxide (ZnO) into a
glass matrix by using the Sol-Gel Technique at room temperature, these
materials were prepared using tetraethyl orthosilicate (TEOS) as precursor,
the Zn ions were added before the jellification step trough an aqueous
solution of zinc acetate. These glasses were characterized by X-ray
diffraction, optic absorption, FT-IR and Raman spectroscopy. The X-ray
patterns showed amorphousness. The optical absorption shows a shoulder in the
UV range corresponding whit ZnO confined to the vitreous matrix. The spectra
by FT-IR show characteristic vibrations of Si-O-Si with interaction Zn+2.
Raman scattering let us to identify and precise the formation of the ZnO. In
the second part of this work was immersed glass substrates into an aqueous
chemical bath with external controlled temperature, the chemical solutions
contained in the bath were a Zn Ions source (ZnSO4) 0.1 M, a pH 10 Buffer
solution (NH4Cl/NH4OH), Ethanolamine to complex the Zn ions, and pure water,
resulting ZnO films hexagonally structured with energy band gap of 3.3 eV,
growing 1000 nm during 25 minutes followed of 60 minutes to 75°C and 85°C in
the same chemical reaction.
Keywords: Glasses, Zn
Ions, Zinc Oxide, Sol-Gel Process, Thin Films, Chemical Bath Deposition and
semiconductors
Title of the Paper: Efficient
Interconnect Design with Novel Repeater Insertion for Low Power Applications
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Authors:
Tripti Sharma, K. G. Sharma, B. P. Singh, Neha Arora
Abstract: Length of interconnect and number of repeaters are increasing with
the advancement in VLSI Technology. Requirement of repeaters is increasing as
the length of interconnect is increasing. The power delay product and
frequency of operation plays significant role in designing of repeater.
Performance of earlier conventional repeater with the proposed sub-threshold
grounded body (STGB) bias repeater for various lengths of interconnects is
analyzed. The simulation results shown in the paper indicates that the STGB
bias repeater circuit operates in medium frequency range with better
power-delay product as compared with the previous repeater. The temperature
sustainability and performance with the variation of aspect ratio is also
better for STGB bias repeater. Reduction of overall delay, power dissipation
as well as operation of the repeater at higher frequencies can lead to the
better performance of the VLSI chip in sub-threshold region.
Keywords: VLSI,
Interconnect, Sub-threshold, Repeater, Buffer, novel approach, conventional
buffer, portable applications
Title of the Paper: Investigation of
the Heat Meters Calculator Applying a Measurement Devices Software Reliability
Method
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Authors:
V. Knyva, M. Knyva
Abstract: Nowadays, parameters, characteristics and functionality of
measurement devices basically depend on microprocessors software. Software
used in measurement devices overtakes functions from a hardware part of the
device. For example, data processing algorithms, control functions are
implemented using software. Basically during verification of the device, just
a hardware part of the device is verified. But software controls all the
functions of the measurement device. Therefore, a method for metrological
estimation of reliability of measurement devices software will be presented.
Keywords: Software
validation, metrology, measurement devices, verification and testing of
software
Title of the Paper: Adiabatic and
Standard CMOS Interfaces at 90 nm Technology
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Authors:
Neha Arora, B. P.Singh, Tripti Sharma, K. G. Sharma
Abstract: Adiabatic circuits and standard CMOS logic are widely employed in
Low power VLSI chips to achieve high system performance. The power saving of
adiabatic circuit can reach more than 90% compared to conventional static CMOS
logic. The clocking schemes and signal waveforms of adiabatic are different
from those of standard CMOS circuits. This paper investigates the design
approaches of low power interface circuits in terms of energy dissipation.
Several low power interface circuits that convert signals between adiabatic
logic and standard CMOS circuits are presented. With BSIM3v3 90nm CMOS
technology, the energy consumption of proposed interface circuits has
relatively large power saving over the wide range of frequencies. This paper
also investigates the different power delay product over the wide range of
supply voltages. Power dissipation has been calculated for different values of
temperature. The proposed circuits are showing the best results on various
ranges of temperature. Simulation has been done on tanner EDA tool at BSIM3v3
90nm technology.
Keywords: Standard CMOS
logic, adiabatic circuit, Interfaces, Low power, Power delay Product, Energy
dissipation, Power Dissipation
Title of the Paper: Application of
Genetic Algorithms for Optimal Reactive Power Planning of Doubly Fed Induction
Generators
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Authors:
P. Sangsarawut, A. Oonsivilai, T. Kulworawanichpong
Abstract: This paper describes optimal reactive power control of a doubly fed
induction generator (DFIG), which is widely used in a distributed generating
plant. Although its structure is similar to that of induction motors, its
reactive power control is more complicated. In this paper, steady-state power
transfer equations are derived and developed for a doubly fed structure of the
induction generators. When a distributed power plant equipped with DFIGs is
connected to a regional power grid, reactive power injection from the plant
results in distribution system performances, e.g. voltage drop, power losses,
etc. By using genetic algorithms, optimal reactive power injection can be
achieved in order to minimize total power loss in power distribution systems.
The 37-node IEEE standard test feeder is used to evaluate its performances. As
a result, optimal reactive power control of DFIGs can reduce total power
losses and also improve voltage profiles in power distribution systems.
Keywords: Optimal reactive
power planning, doubly fed induction generator, optimization, genetic
algorithms
Issue 4, Volume 9,
April 2010
Title of the Paper: Development and
Calibration of an Impulse Magnetic Field Measurement System for Lightning
Electromagnetic Pulse Investigation
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Authors:
Xiao-Ming Ren, Zheng-Cai Fu, Wei Sun
Abstract: In order to evaluate the impulse magnetic field distribution inside
buildings truck by lightning or by nearby stokes, a set of measuring system
composed of self-made magnetic detection coil and fiber transmission system
was developed. The sensitivity coefficient of the optical fiber transmission
system was calibrated by sine wave generator. Connecting the output of a
portable 8/20μs current generator with a circular coil whose diameter is 0.3 m
to compose the magnetic field generator, the detection coil was fixed in the
center of the circular coil for calibration. The B/V calibrated coefficient
error of the system is less than 3%. A demonstrating application of the
developed measurement system is in the investigation of the electromagnetic
environment in buildings under direct and nearby lightning strokes.
Experimental verification of such application has been carried out on metal
frame structure models of building in laboratory. Two scaled metal frame
structure models are set up in the laboratory. The measured transient magnetic
field distributions inside the building frame structures are verified by
comparison of the testing results with the calculated results using the
circuit method simulation. In the circuit method, the lightning channel and
the building’s metal cage are modeled by a multi-conductor system. Every
branch conductor is divided into several suitable segments. The length of each
segment is less than one tenth of the wavelength corresponding to the maximum
frequency in the equivalent spectrum of the lightning transient current. Each
segment is modeled by a coupled -type lumped circuit. The test results of the
developed measurement system coincide with the calculated results well. Under
the situation of nearby lightning strokes, the developed measurement system is
also used for the investigation of the shielding effectiveness of the building
frame structure. The test results of the shielding effectiveness on the metal
frame structure model shows that the effectiveness coefficient increases with
the decrease of grid width of the frame. While the width of the grid changes
from 0.5m to 0.25m, there is an increase of shielding effectiveness of
approximately 10.2%. While the width of grid changes from 0.25 m to 0.125 m,
the shielding effectiveness increases about 5%. To simulate the situation when
metal plate wall exists in the building, 0.5 mm steel plate was attached on
the frame structure model. Under such situation, the shielding effectiveness
increases to 4.9. The application experiments of the developed measurement
system show that it can fulfill the requirements of lightning impulse magnetic
field measurement.
Keywords: Impulse magnetic
field, calibration, magnetic field generator, magnetic field measurement,
lightning protection, fiber transmission system
Title of the Paper: Analysis and
Control of Two Switches AC Chopper Voltage Regulator
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Authors:
Jin Nan, Tang Hou-Jun, Bai Liang-Yu, Geng Xin, Yang Xiao-Liang
Abstract: In this paper, an improved topology of Buck type AC chopper voltage
regulator and its control strategy are proposed. This converter only using two
power switches is low cost, easy implemented and the phase synchronized
circuit is not needed. The current path is provided in dead-time period by
using simple snubber circuit. The over-voltage protection varistor is also
applied to absorb the voltage spikes which may destroy the power switches. The
voltage spikes in dead-time mode commutation are greatly reduced and the power
switches are protected. Furthermore, the feedforward and feedback control
strategy is proposed to suppress fluctuations and eliminate the harmonic
components caused by power quality problems of the input voltage. The proposed
converter could realize wide range voltage regulation with high power transfer
efficiency and low total harmonic distortion. The steady-state equivalent
circuit and the input power factor are derived through theoretical analysis.
The output filter design method is also presented. Based on the theoretical
analysis and calculation, an experimental prototype is setup. The simulation
and experiment results verify the validity of the proposed design.
Keywords: AC chopper,
Voltage Regulator, Pulse Width Modulation, Feedforward and Feedback Control,
Power Factor, Voltage Fluctuations
Title of the Paper: Fault Tolerance
Design by Accurate SER Estimation for Nano-Scale Circuits
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Authors:
Yu Changhong
Abstract: As the transistor sizes continue to shrink, quantum effects will
significantly affect the circuit behavior. The inherent unreliability of
nano-electronics will have significantly impact on the way of circuits design,
so defects and faults of nano-scale circuit technologies have to be taken into
account early in the design of digital systems. Fault-tolerant architectures
may become a necessity to ensure that the underlying circuit could function
properly. In CAD software, a same logic can be made out with different
circuits but different design methodology can reach different soft error
tolerance ability, so we must find a way to estimate the error rate of the
circuit efficiently to make the design more fault tolerant. In this paper, a
new way to fault tolerance design in nano-scale circuit by accurate soft error
rate (SER) estimation is proposed. Transform matrix is used for SER
computation and a design criteria is then proposed. Simulation results show
that the proposed transform matrix model is effective for nano-scale circuits
and the criteria delivered is suitable CAD tools development in nano-system
design.
Keywords: Nano-system, SER
estimation, Transform matrix, Matrix analysis, Condition number, Fault
tolerant design
Title of the Paper: Nonlinear Adaptive
Controller Design of SSSC for Damping Inter-Area Oscillation
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Authors:
Lihong Gu, Xiaoxin Zhou, Min Liu, Haobo Shi
Abstract: This paper presents a novel nonlinear adaptive control scheme of
static synchronous series compensator (SSSC) to enhance the transmission power
and damping of inter-area oscillation mode for multi-machine power system..
The SSSC device was treated as a first order voltage resource and the
multi-machine system was simplified into a two-machine model. Based on the
exact feedback linearization theory, Lyapunov stability theory, and adaptive
control law, the nonlinear adaptive controller of SSSC is derived. Unknown
system parameters are considered for improving robustness. The simulation
results validate the efficacy of the proposed controller.
Keywords: Power system,
SSSC, inter-area oscillation, nonlinear adaptive control, Lyapnuov stability
Title of the Paper: Infrared Thermal
Detectors Parameters: Semiconductor Bolometers Versus Pyroelectrics
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Authors:
Genc Hyseni, Nebi Caka, Kujtim Hyseni
Abstract: Semiconductor bolometric detectors parameters have been analyzed
within the wavelength of 100μm up to 3mm and cryogenic temperatures. From
analyses and results obtained, it is shown that the values of NEP have been
found to be 16.4?10-15W/Hz-1/2 and 38.466?10-15W/Hz-1/2 for cryogenic
temperatures 0.5K and 5K, respectively. For the wavelength 200 μm, the maximum
value of the voltage responsivity RV of the bolometer is 0.106?10-11 V/W,
while for the wavelengths 1 mm, 2 mm and 3 mm, corresponding values of voltage
responsivity RV of the bolometer are 0.53?10-11 V/W, 0.58?10-11 V/W and
0.637?10-11 V/W, respectively. This paper also outlines analyzes of the
temperature dependency of infrared pyroelectric detectors parameters at medium
wavelength (MWIR). Certain pyroelectric materials such as TGS, LiTaO3, LiNbO3,
Li2SO4xH2O, BaTiO3, NaNO2, PVF2, SBN and SbSi have been analyzed within the
temperature range of 273K up to 343K. Analytically it is proven that thermal
time constant decreases with increasing temperature and decreasing the
thickness of the detector. Analyses have shown that the smallest response time
for detector which operates at room temperature 300K was achieved for the
material Li2SO4?H2O with value of several milliseconds, but anyway much
greater then that of photon detectors. It is also shown that NEP depends
directly on circuit noises voltages. In the paper are analyzed three types of
noises: thermal noise, dielectric noise, and amplifier noise. The maximum
possible value of detectivity to be achieved for a MWIR infrared pyroelectric
detector operates at room temperature 300K was 2.12?108 for NaNO2.
Keywords: Infrared,
bolometers, pyroelectricity, pyroelectric detectors, responsivity, thermal
time constant, NEP, detectivity
Title of the Paper: Preservation of
Synchronization in Dynamical Systems via Lyapunov Methods
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Authors:
G. Fernandez Anaya, C. Rodriguez Lucatero, J. J. Flores-Godoy, C.
Miranda-Reyes
Abstract: In this paper, we use, extend and apply some classic results of the
theory of dynamical systems to study the preservation of synchronization in
chaotical dynamical systems via Lyapunov method. The obtained results show
that synchronization can be preserved after a particular class of changes are
made to the linear part of the dynamical system. For illustrative purposes we
apply a compound control law to achieve synchronization in a master-slave
system. We also show that it is possible to preserve partial synchronization
when an additive perturbation is included in the control law. We present
numerical simulations to show the effectiveness of our method.
Keywords: Chaotic Systems,
control theory, convergence, stability
Title of the Paper: An Implementation
of Parallel Power Flow Calculation based on Graph Partitioning Algorithm
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Authors:
Wenkai Zhao, Xinyan Fang, Xu Dong, Yuan Bi, Ying Wu
Abstract: In coarse-grained parallelism, it is effective to partition the
network into Bordered Block Diagonal Form (BBDF) before subsequent parallel
computation. An implementation of parallel power flow calculation based on a
novel graph partitioning algorithm, which transforms the admittance matrix
into nested BBDF (NBBDF),is presented in this paper. In order to avoid
excessive fill-ins during Gaussian elimination, a vertex ordering scheme is
discussed. Distributed file storage combined with task scheduling is proposed
for improving parallel efficiency. Testing results for grids with up to 5317
buses indicate that this proposed method is able to bring superlinearity into
parallel power flow calculation for large-scale power systems.
Keywords: Parallel power
flow calculation, power systems, graph partitioning algorithm
Title of the Paper: A Ring Oscillator
of Remarkable Power Supply Independent Characteristic
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Authors:
Mohammad Hassan Montaseri
Abstract: A highly power supply independent Ring Oscillator architecture is
proposed in this paper. The proposed architecture is achieved using the
advantages of best previous techniques. Making use of opposite characteristics
of the delay cells along with power supply isolation and self-biasing have
resulted in a nearly 1% sensitivity; a record better than all previous
architectures. To accomplish such robustness, different delay stages with
different characteristics have been used in the proposed architecture.
Simulations based on 0.5μm CMOS technology confirm robustness of the proposal.
Keywords: Ring Oscillator,
Voltage Controlled Ring Oscillator, Power Supply Variation, Frequency
Stability
Issue 5, Volume 9,
May 2010
Title of the Paper: A Ring Oscillator
with High Temperature Independency
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Authors:
Mohammad Hassan Montaseri
Abstract: A novel temperature independent Ring Oscillator is proposed in this
paper. In order to accomplish temperature independency, different
characteristics of several delay stages are gathered together in one circuit
scheme. Using the temperature property of one kind of delay stage to cancel
the other’s, has made the proposed architecture show drastically low
temperature sensitivity. The proposed architecture was simulated in 0.35μm
CMOS technology where the temperature varied from 0 to 50 degrees Celsius,
resulting in only 1% frequency deviations.
Keywords: Ring Oscillator,
Voltage Controlled Oscillators, Ring Oscillators, Temperature Variations,
Frequency Stability
Title of the Paper: Transport
Supervision of Perishable Goods by Embedded Context Aware Objects
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Authors:
A. Wessels, R. Jedermann, W. Lang
Abstract: Intelligent freight objects can be introduced in order to simplify
the solution of complex logistical planning tasks. This enables splitting
logistical problems to local executable subtasks. The concept of Ubiquitous
Computing (UbiComp) presents a model to realize such intelligent objects. A
local task can be handled autonomously by a group of objects. The realization
of UbiComp needs a platform that first provides the computational resources
for the implementation of decision algorithms and then, secondly, the position
information in order to enable context-aware features. This article presents a
concept for the autonomous supervision of perishable goods and introduces the
required soft- and hardware. Freight objects are represented by individual
software components, which are realized with the JAVA framework OSGi. The
whole software is designed to run on wireless sensor nodes to create embedded
objects. Because temperature values can differ inside a reefer container, the
signal strength of an RFID reader is used to provide position information by a
cell based localization. A new approach is presented, where four RFID antennas
are used to locate goods inside a container.
Keywords: Ubiquitous
Computing, embedded Systems, JAVA, OSGi, localization, RFID, RSSI
Title of the Paper: Design of a Simple
OTA-Based Mixed-Signal Controller for Adaptive Control System of Shunt Active
Power Filter
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Authors:
Sombat Vanichprapa, Cherdchai Prapanavarat, Boonruk Chipipop
Abstract: This paper presents a simple mixed-signal controller using OTA
(Operational Transconductance Amplifier) – based circuit for the adaptive
control system of shunt active power filter (APF). The DC bus voltage
detection method is proposed for the control scheme. The simple OTA multiplier
circuit, OTA-C Canonical second-order filter circuit and OTA-C plus OTA
summator circuit is designed for the reference-sine-wave signal generator
including Low Pass Filter and PI controller. The LM13700 is represented for
the OTA simulated model which is developed for using with the 50 Hz
three-phase three-wire system utility. The advantage of using OTAbased
circuits is its adaptive control and real-time processing which is suitable
for high frequency power switches of the active power filter without using A/D
converter. The simulation results show that OTA-based circuit can be used as
the adaptive controller of APF which is simpler design compared to DSP,
moreover, it can be fabricated in one single chip by using CMOS technology.
Keywords: Active power
filter, adaptive, circuits, controller, mixed-signal, OTA, simple
Title of the Paper: A VHDL-Based Design
Methodology for Asynchronous Circuits
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Authors:
Sun-Yen Tan, Wen-Tzeng Huang
Abstract: The asynchronous circuit style is based on micropipelines, a style
used to develop asynchronous microprocessors at Manchester University. This
paper has presented some engineering work on developing a micropipeline
blocksorter. The work presented in this paper demonstrates that VHDL can be
used to describe the behaviour of micropipelined systems. It also shows a
comparison of 2-phase and 4-phase implementations in transistor count, speed,
and energy. Though the nature of the work is mainly engineering, there are
some significant new insights gained in the course of the work. In summary, a
design environment for asynchronous circuits has been established based upon
the micropipeline style and VHDL, a standard hardware description language.
Keywords: Asynchronous
design, Micropipelines, Blocksorter, VHDL, Synthesis
Title of the Paper: Piezoresistive
Microcantilever Biosensor Potentiometric Signal Transduction for Human Stress
Measurement
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Authors:
Nina Korlina Madzhi, Anuar Ahmad, Lee Yoot Khuan, Mohd Firdaus Abdullah
Abstract: This paper deals with the development of Piezoresistive
Microcantilever biosensor and the signal transduction to detect human stress
by using salivary alpha amylase activity. A Piezoresistive Microcantilever
biosensor can be used to detect saliva-amylase activity by deflecting upon
interaction with a specific receptor. By measuring the amount of bending the
microcantilever beam experiences in response to interactions with the
molecules, and the amount of analyte in the solution can be quantified. When
the Microcantilever beam deflects it caused the stress change within the
microcantilever beam and applied strain to the piezoresistor material thereby
causing the resistance change which can be measured with the Wheatstone Bridge
circuit. The Piezoresistive Microcantilever sensor integrated with transducer
components converts the biochemical signal into measurable signal when it
react with salivary amylase enzyme. The enzyme concentration signal is
converted to a voltage signal by the transducer. The device was designed
specifically that it enables the small resistivity change due to the enzymatic
reaction to be measured.
Keywords: Biosensor,
Piezoresistive, Microcantilever, Signal Transduction, Resistance change,
Saliva, Alpha Amylase
Title of the Paper: A Novel Linear
Array for Discrete Cosine Transform
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Authors:
Yaw-Shih Shieh, Tze-Yun Sung, Hsi-Chin Hsin
Abstract: Discrete cosine transform (DCT) and inverse DCT (IDCT) have been
widely used in many image processing systems. In this paper, a novel
linear-array of DCT and IDCT is derived from the data flow of subband
decompositions representing the factorized coefficient matrices in the matrix
formulation of the recursive algorithm. For increasing the throughput as well
as decreasing the hardware cost, the input and output data are reordered. The
proposed 8-point DCT/IDCT processor with four multipliers, simple adders, and
less registers and ROM storing the immediate results and coefficients,
respectively, has been implemented on FPGA. The linear-array DCT/IDCT
processor with the computation complexity O(5N / 8) and hardware complexity
O(N / 2) is fully pipelined and scalable for variable length DCT/IDCT
computations.
Keywords: DCT/IDCT,
subband decomposition, linear-array, pipelined, scalable
Title of the Paper: Reconfigurable
Architecture for VLSI 9/7-5/3 Wavelet Filter
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Authors:
Tze-Yun Sung, Hsi-Chin Hsin
Abstract: In this paper, the high-efficient and reconfigurable lined-based
architectures for the 9/7-5/3 discrete wavelet transform (DWT) based on
lifting scheme are proposed. The proposed parallel and pipelined architectures
consist of a horizontal filter (HF) and a vertical filter (VF). The critical
paths of the proposed architectures are reduced. Filter coefficients of the
biorthogonal 9/7-5/3 wavelet low-pass filter are quantized before
implementation in the high-speed computation hardware In the proposed
architectures, all multiplications are performed using less shifts and
additions. The proposed reconfigurable architecture is 100% hardware
utilization and ultra low-power. The proposed reconfigurable architectures
have regular structure, simple control flow, high throughput and high
scalability. Thus, they are very suitable for new-generation image compression
systems, such as JPEG-2000.
Keywords: Reconfigurable
architecture, 9/7-5/3 discrete wavelet transform (DWT), horizontal filter
(HF), vertical filter (VF), lifting scheme
Title of the Paper: Multiplierless,
Reconfigurable Folded Architecture for VLSI Wavelet Filter
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Authors:
Tze-Yun Sung, Hsi-Chin Hsin, Sheng-Dong Chang
Abstract: In this paper, the high-efficient and reconfigurable architectures
for the 9/7-5/3 discrete wavelet transform (DWT) based on convolution scheme
are proposed. The proposed parallel and pipelined architectures consist of a
high-pass filter (HF) and a low-pass filter (LF). The critical paths of the
proposed architectures are reduced. Filter coefficients of the biorthogonal
9/7-5/3 wavelet low-pass filter are quantized before implementation in the
high-speed computation hardware. In the proposed architectures, all
multiplications are performed using less shifts and additions. The proposed
reconfigurable architecture is 100% hardware utilization and ultra low-power.
The proposed reconfigurable architectures have regular structure, simple
control flow, high throughput and high scalability. Thus, they are very
suitable for new-generation image compression systems, such as JPEG-2000.
Keywords: Folded
reconfigurable architecture, 9/7-5/3 discrete wavelet transform (DWT),
high-pass filter (HF), low-pass filter (LF), convolution scheme
Issue 6, Volume 9,
June 2010
Title of the Paper: Adder Designs using
Reversible Logic Gates
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Authors:
P. K. Lala, J. P. Parkerson, P. Chakraborty
Abstract: A new reversible logic gate was proposed in Ref. [1]. This gate can
be used to implement any classical Boolean logic function. This paper shows
the application of the reversible gate in implementing ripple carry, carry
skip and carry look-ahead adders. These adders are more efficient than adders
implemented using Fredkin Gates
Keywords: Reversible
logic, Fredkin gate, garbage output, adder design
Title of the Paper: Development of
Piezoelectric Braille Cell Control System Using Microcontroller Unit (MCU)
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Authors:
S. Mad Saad, F. Razaly, M. Z. Md Zain, M. Hussein, M. S. Yaacob, A. R. Musa,
M. Y. Abdullah
Abstract: This paper describes about designing and developing a system for
controlling piezoelectric Braille cell by using Programmable Interface
Controller (PIC) microcontroller. For this purpose, PIC microcontroller is
used as a controller to the system for controlling the piezoelectric Braille
cell. Piezoelectric Braille cells are used in many refreshable Braille display
applications. The Braille displays using piezoelectric Braille cell are able
to refresh the Braille character that are read by the visually impaired by
touching the dots at Braille cell. Each piezoelectric Braille cell consisting
of six or eight movable pins or dots in rectangular array. The height of pins
or dots in Braille cell is controlled by a piezoelectric bimorph. This will
cause the pins or dots at piezoelectric Braille cell to rise or fall and
therefore, create the Braille character or alphabet. Throughout the paper, the
pin or dots at piezoelectric Braille cell which represent a certain Braille
character is also presented. The architecture and operation of the system is
discussed in detail, considering both the hardware and software elements
involved. The software for programming the PIC microcontroller was written
with CCS C program language. The system is developed and tested successfully.
This system can be applied in the Braille Display which uses the piezoelectric
Braille cell to display some of Braille characters.
Keywords: Piezoelectric
Braille cell; PIC Microcontroller; CCS C program language
Title of the Paper: Discussion on the
Algorithms of a New Siphon Rain Gauge
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Authors:
Hong-Yang Li, Qing Li, Xiong Li, Jia-Long Song
Abstract: As the persistent rain within a short time may trigger off mud-flows
and landslides which cause great losses to lives and properties, the real-time
monitoring work of rainfall is very meaningful to the disaster early warning.
In order to get the accurate rainfall data timely in the unattended wilderness
environment, this paper presents a novel siphon rain gauge design based on a
strain-type pressure sensor after an integrated consideration of the
principles, operation methods, merits and faults of various types of rain
gauges. This rain gauge not only keeps the advantages of the traditional
siphon rain gauge such as low power and not subject to the restrictions of
rainfall’s intensity, but also ensures the measurement accuracy by a pressure
sensor, besides, the rainfall in the process of siphon can be compensated by
the compensation algorithm. Finally, the algorithm optimized data can be
transmitted over long-distance through the GSM module on the data collector,
thus its scope of application will be greatly increased.
Keywords: Rain gauge,
siphon, low power, long-distance transmission, curve fit
Title of the Paper: High Precision Time
and Frequency Counter for Mobile Applications
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Authors:
R. Szplet, Z. Jachna, K. Rozyc, J. Kalisz
Abstract: This paper presents the design, architecture, operation, and test
results of a high precision time interval and frequency counter made as a
small, portable instrument with USB interface. Thanks to the use of advanced
time interpolators integrated in a CMOS chip, the precision (standard
deviation) below 35 ps was obtained at measured time interval from 0 to 200
ms. The frequency can be measured up to 3.5 GHz. Due to the very short dead
time of the counter the maximum measurement rate of 5 million measurements per
second is achieved. The dedicated control software creates a user-friendly and
versatile graphic interface in Windows environment. Reprogrammable CMOS
technology used in the counter allows easy customizing of the instrument to
match many specific applications.
Keywords: Time interval
counter, time digitizer, time-to-digital converter, time interpolation,
two-stage interpolation
Title of the Paper: Eddy Current
Testing in Height Measurement of Copper Cylinder and its 2D Electromagnetic
Field Simulation
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Authors:
Yanjie Wang, Qing Li, Xiong Li
Abstract: In this article, this measurement result was found that the
fluctuation amplitude of the coil’s inherent inductance L gradually reduces
with increasing of frequancecy while the fluctuation amplitude of the coil’s
inherent resistance R gradually increases with the increasing of frequancecy.
According to the basic principle of eddy current testing, some experiments in
this paper proved that the equivalent resistance R and the equivalent
impedance Z of the eddy current testing equivalent circuit is unstable in
repeated measurements, but the equivalent inductance L has a good stability
and can be used to measure the height of copper cylinder at an appropriate
frequancecy after doing a calibration between the equivalent inductance L and
the height of copper cylinder. Besides, the abnormal measurement result of the
equivalent inductance L was illustrated by the finite element electromagnetic
field simulation when the copper cylinder is too high.
Keywords: Eddy current
testing; Height measurement of copper cylinder; The finite element
Title of the Paper: Micro-Robots used
in Control of Automatic Drilling Operations
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Authors:
Paul Ciprian Patic, Mihaita Ardeleanu, Florin Popa
Abstract: A micro-assembly station based on a micro-robot, under an optical
microscope, is one of the typical styles to practical application of the task
of assembling simple micro parts, even if they are still almost at the start
phase. The performance of the micro-robotic system has the potential to have
an important role in such applications with reference to the transportation,
handling and storage of micro objects. For that, has developed an automated
system consisting of multiple drilling micro-robots. In this paper is
presented a concept of control for automated micro-drilling, “cluster” type,
in which several miniature robots, piezoelectric trained, are used to
transport the piece of work to hold and to permit the micro-borer
introduction. This type may provide some advantages having in view the
accuracy and flexibility of micro fabrication.
Keywords: Micro-robot,
Actuator, Micro-controller, Drill, CCD Camera, DC motor, Dynamic Modeling
Title of the Paper: Study of the
Operating States of Intrinsic Safety Barriers of the Electric Equipment
Intended for Use in Atmospheres with Explosion Hazard
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Authors:
Niculescu Titu, Pasculescu Dragos, Pana Leon
Abstract: Electrical equipments destined to operate in potentially hazardous
environments are externally connected through intrinsic safety barriers. Their
gauging should observe th e safety standards in the field and it is made on
grounds of a theoretical analysis, on which this paper focuses. The analysis
of the safety barrier involves the consideration for three important regimes:
the aperiodic regime, the aperiodic critical regim and the oscillatory regime.
To this purpose, a theoretical analysis of the barrier was made, in which the
uniformly distributed parameters were considered to be concentrated. For each
of the situations mentioned above, the analytical expressions of the output
voltage and of the current through the barrier were inferred. The analysis of
the safety barrier is made in MATLAB environment, through numerical simulation
in SIMULINK.
Keywords: Equipment,
Explosion hazard, MATLAB, Diagram, Safety barrier
Issue 7, Volume 9,
July 2010
Title of the Paper: Bio-Inspired Visual
Information Processing – The Neuromorphic Approach
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Authors:
W. J. Han, S. D. Kim, I. S. Han
Abstract: This paper describes the bio-inspired visual inforamtion processing
by neuromorphic system, mimicking the primitive behaviour of visual cortex.
The neuromorphic components are investigated for implementation of the visual
signal selectivity of cortex, based on the CMOS conductance-based synaptic
connections and neurons of Hodgkin-Huxley formalism. The proposed neuromorphic
system exhibits the biologically plausible function mimicking the cat’s visual
cortex experimentation of Hubel and Wiesel. The detection of vehicle object or
human head figure demonstrates the feasibilty of vision applications.
Keywords: Neural networks,
CMOS, vision, neuromorphic, visual cortex, simple cell, Hodgkin-Huxley
formalism
Title of the Paper: Design of Accurate
Power Factor Measurement Approach Using FPGA-based Chip
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Authors:
Shu-Chen Wang, Chi-Jui Wu
Abstract: In recent years, power electronic components introduce harmonic
pollution on electric power systems. It makes the traditional
electromechanical power meter can not act accurately when it feeds unbalanced
and harmonic loads. Power quality analysis now tends to use digital signal
technology. But it is hard to avoid measurement errors in estimating power
quality by digital signal technology. In this paper, it is to improve the
computation errors by using FPGA. The simulation circuits were created and
measured by Matlab. Then it will discuss the case of single-phase full-wave
bridge rectifier loads. And then in the three-phase circuit the effective
power factor, arithmetic power factor, and fundamental power factor will be
compared in several simulation cases. The computation errors have been greatly
reduced. In the study, the Fast Fourier Transform (FFT) is used to analyze the
formula of power factor. The simulation system was modeled in Hardware
Description Language (VHDL) and some novel IP (intellectual property) cores,
such as CORDIC core and FFT core by the way of Bottom-Up. Design of SOC
(System on a Chip) is a trend to achieve the strong and small volume in the
future.
Keywords: Power Quality,
Harmonic, Unbalance, FPGA, FFT
Title of the Paper: Study on Ultrasonic
Detecting Technology of Profiled Component
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Authors:
Yanhua Zhang, Lu Yang, Haijun Cao
Abstract: The profiled component has some structural features, such as thin
wall, small diameter and corner angle on inner wall. The features make it very
difficult to detect the profiled component with non-destructive examination
method. According to the principle of ultrasonic creeping wave, a grouped
ultrasonic detecting method is put forward to detect the standard defects in
inner and outer of profiled component. Based on comparing defect echo with
inner edge wave, feature extraction method of two characteristics of amplitude
and time is put forward to extract defects and to eliminate the interference
of inner edge wave. In order to overcome the one-sidedness disadvantage of
single probe data, data fusion technology of synthesis local decisions of
three probes is used to determine defects, which improves the accuracy of
defect judgement. Three characteristic values of period, duration time and
amplitude of echo signal are used to comprehensively evaluate the defect type.
The testing results indicate that the detection method and signal processing
method can meet the application requirements of accuracy and reliability, and
it would have good application foreground for on-line detection.
Keywords: Profiled
component, creeping wave, inner edge wave, time characteristic, amplitude
characteristic, data Fusion
Title of the Paper: Odd/Even Scroll
Generation with Inductorless Chua's and Wien Bridge Oscillator Circuits
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Authors:
Watcharin Jantanate, Peter A. Chaiyasena, Sarawut Sujitjorn
Abstract: An inductorless Chua’s circuit, and a scroll generator are presented
in this paper. The scheme employs only RCs and op-amps, and provides a very
reliable generation of multiple odd and even chaotic scrolls. The design
formulas and examples including simulation and practical results are
illustrated. The principle has been applied successfully to generate some
odd/even scrolls with the Wien bridge oscillator as illustrated by the
simulation and the practical results.
Keywords: Chaos, Chua’s
circuit, inductorless, Wien bride oscillator, scroll generation
Title of the Paper: Isolated Zeta
Converter: Principle of Operation and Design in Continuous Conduction Mode
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Authors:
Pijit Kochcha, Sarawut Sujitjorn
Abstract: The principle of operation of the zeta converter is explained in the
article. Small-signal and steady-state models of the converter are presented.
The design formulas for the continuous conduction mode (CCM) are given
together with some design examples and simulation results. The power factor
and harmonic issues are also addressed.
Keywords: Zeta converter,
continuous conduction mode (CCM), harmonic, power factor
Title of the Paper: Symbolic Equation
for Linear Analog Electrical Circuits using Matlab
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Authors:
Zoltan Erdei, Luiza Alexandra Dicso, Liviu Neamt, Oliver Chiver
Abstract: In this paper is presented a program which generates the modified
nodal equation for electric analog circuits in a symbolic, partial symbolic
and numerical mode. The program is an application, made in the environment of
the program MATLAB version 7.1, which has a powerful symbolic math toolbox.
MATLAB is a high-performance software package dedicated for numerical analysis
and graphic representations in engineering applications. In this paper we try
to explore the capabilities of this program in symbolic domain.
Keywords: Analog circuits,
circuit functions, symbolic equations, Matlab, netlist, modified nodal
analysis
Title of the Paper: Aircrafts' Altitude
Measurement Using Pressure Information: Barometric Altitude and Density
Altitude
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Authors:
Teodor Lucian Grigorie, Liviu Dinca, Jenica-Ileana Corcau, Otilia Grigorie
Abstract: The paper is a review of the pressure method used in the aircrafts’
altitude measurement. In a short introduction the basic methods used in
aviation for altitude determination are nominated, and the importance of the
barometric altitude is pointed. Further, the atmosphere stratification is
presented and the general differential equation, which gives the dependence of
the static pressure by the altitude, is deduced. The barometric and the
hypsometric formulas for the first four atmospheric layers are developed both
in the analytical and numerical forms. Also, the paper presents a method to
determinate the density altitude with an electronic flight instrument system.
A brief review of the flight altitudes is performed, and the calculus
relations of the density altitude are developed. The first two atmospheric
layers (0?11 Km and 11?20 Km) are considered. For different indicated
barometric altitudes an evaluation of the density altitude, as a function of
non-standards temperature variations and of dew point value, is realized.
Keywords: Standard
atmosphere, atmospheric layers, barometric formula, density-altitude,
evaluation
Issue 8, Volume 9,
August 2010
Title of the Paper: Second Harmonic
Signal Detection on Poly[μ2-L-alanine-μ3-nitratosodium (I)] Crystals
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Authors:
E. Gallegos-Loya, E. Alvarez Ramos, E. Regalado, A. Duarte-Moller
Abstract: Crystals of poly (L-alanine sodium nitrate) have been grown by the
slow evaporation at room temperature method. Crystal sizes of 500mm and 10 mm
were obtained. UV-vis spectrum shows a wide transparent window where lake of
absorption around the 532 nm. By other hand the FTIR analysis displays its
functional groups corresponding to the alanine. The Single Crystal Diffraction
experiment was carried out in order to determine the atomic structure and its
lattice parameter. Finally as a first time the second harmonic generation was
measure by using a variant of the Kurtz Perry method. The efficiency was
plotted and discussed.
Keywords: L- alanine, SHG,
NLO, semiorganic, alanine
Title of the Paper: The Effect of the
Output Capacitor on the Power Spectrum of the EMI Radiation, the Output
Voltage Ripple and the Efficiency of a SEPIC Converter
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Authors:
Florian Ion, Marcel Ionel, Gabriel Predusca
Abstract: This paper presents the effect of the output capacitor on the EMI
spectrum of radiation, the output voltage ripple and the efficiency of a SEPIC
Converter. Two SEPIC converters were designed with LT1871 (Linear Technology)
and LM2577 (National Semiconductor), for an input voltage of 4 to 16V, the
output voltage of 5V, output current of 0.5A, and the switching frequency of
52kHz. The functionality of the converter was simulated in LTspice IV and
OrCAD, and it was compared with the experimental results. It was measured the
level of EMI spectrum, the output voltage ripple and the efficiency of the
converter with different types of capacitors. An acceptable output voltage
ripple, which respects the standards FCC Class A and Class B, was obtained
with solid and tantalum capacitors in parallel with small MLCC capacitors. The
minimum of ripple and frequency spectrum was obtained by adding a LC Filter to
the output of the converter. With this filter the converter respects the
standard SAE J1113.
Keywords: SMPS, SEPIC
converter, output voltage ripple, converter’s efficiency, frequency spectrum
Title of the Paper: Application of the
Elliptical Trigonometry in Industrial Electronic Systems with Analyzing,
Modeling and Simulating Two Functions Elliptic Mar and Elliptic Jes-x
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Authors:
Claude Bayeh
Abstract: In industrial electronic systems, specific electronic circuits are
used to produce specific signals. In general, one circuit can?t produce more
than two or three different signals; this is not the case of the Elliptical
Trigonometry, in which one simple circuit can produce more than 12 different
signals. In this paper, the author proposes an original control circuit for
each function in order to replace the different existing circuits. The
proposed circuit is the representation of an elliptical trigonometric function
as “Elliptic Mar” and “Elliptic Jes-x” that are particular cases of the
elliptical trigonometry. Thus, with one function, by varying the values of its
parameters, the output waveform will change and can describe more than 12
different waveforms. Finally, for each function, a block diagram, a model of
the circuit and a programming part are treated using Matlab/Simulink. The
results of the studied circuit are presented and discussed.
Keywords: Power
electronics, power converters, mathematics, trigonometry, multi form signal
Title of the Paper: Negative
Consequence of Motor Voltage Asymmetry and its Influence to the Unefficient
Energy Usage
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Authors:
Miloje Kostic, Aleksandar Nikolic
Abstract: Analysis of the effect of unbalanced voltages on the three-phase
induction motor is presented in the paper. Since the unbalanced voltage of 2%,
3.5% and 5% increase in losses could reach, in the same order, the amount of
8%, 25% and 50% of nominal power losses in the motor, it is reasonable
requirement to permit voltage asymmetry ? 2%, so this is the upper limit in
most national and international standards. The truth is that with a smaller
load, the motor could safely work also at higher values of unbalanced voltage.
The literature states that the information given previosly is determined from
measurements and that they are higher than calculated values. However, it is
explained here by the fact that the rotor inverse resistance is higher by 1.4
times compared to the rotor resistance in short circuit mode, since current
frequency of the negative sequence in the rotor winding is two times higher
(fr,NS ? 2f1=2fr,SC), i.e. it is higher for 1.41 times than corresponding
values given in the literature Thus it is increasingly convinced that the
requirements which are given in most appropriate standards are justified.
Performed analysis show that there are some considerations that could be
included in current standards. Motor operation is not generally allowed when
the values of the coefficient of unbalanced voltage are U1 NS/Un ? 5%, because
in the (rare) case when the direct and inverse component of the stator
currents in (a) phase matching, increase of the current in that phase would be
? 1.38 times, and the increase of the losses in the windings of that phase
would be ? 90%.
Keywords: Negative
sequence voltage, asymetry, power losses, induction motor, energy efficiency,
standard
Title of the Paper: Role of Driver and
Load Transistor (MOSFET) Parameters on Pseudo-NMOS Logic Design
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Authors:
Nebi Caka, Milaim Zabeli, Myzafere Limani, Qamil Kabashi
Abstract: The pseudo-NMOS logic can be used in special applications to perform
special logic function. The pseudo- NMOS logic is based on designing
pseudo-NMOS inverter which functions as a digital switch. During the design
phase of pseudo-NMOS inverters and logic gates based on MOS technologies, it
is necessary to take into consideration many parameters which characterise MOS
transistors, which impact static and dynamic performances of the different
logic gates. The aim of this paper is to research impact the NMOS (driver) and
PMOS (active load) transistors parameters during the design phase of
pseudo-NMOS inverters and in design phase pseudo-NMOS logic gates for
different work cases. The results obtained emphasize the impact of each single
parameter of MOSFET transistor at the low output level state, at the level
values of static current at output, on the shape of the voltage transfer
characteristic in the pseudo-NMOS inverter, on propagation delays during
transition logic state, and impact in pseudo-NMOS logic gates. By adjusting
the parameters values of NMOS and PMOS transistor it’s possible to design
pseudo-NMOS inverters and pseudo-NMOS logic gate which will have acceptable
performance depending on designers’ requests.
Keywords: Threshold
Voltage, Driver Transistor, Active Load, Device Transconductance Parameter,
Voltage Level, Low Output Level, VTC- Characteristic, Static Current,
Propagation Delays, Fan-In
Issue 9, Volume 9,
September 2010
Title of the Paper: ECO-Aware
Obstacle-Avoiding Routing Tree Algorithm
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Authors:
Jui-Hung Hung, Yao-Kai Yeh, Yu-Cheng Lin, Hsin-Hsiung Huang, Tsai-Ming Hsieh
Abstract: This study formulates a novel routing problem of engineering change
order- (ECO for short) aware Steiner minimal tree with obstacles and solves it
by a multiple-stage approach, including partitioning, analysis distribution of
spare cells, virtual node insertion and diagonal-based routing tree
construction. The objective of this paper is to construct an ECO-aware routing
tree in the sense of ECO resources. The number of available spare cells near
the routing tree significantly increases while minimizing the additional
length compared to the original tree algorithm. To efficiently analyze, an
entire chip is divided into a set of fixed-size grids and the number of spare
cells in each grid is calculated. To reduce the additional length, we insert
the number of user-defined virtual nodes, which represent the grids with more
spare cells. Furthermore, a graph-based routing algorithm is used to construct
an X-architecture tree. To further reduce total wire length, each segment in
the spanning tree is transferred into the corresponding combination of
vertical, horizontal and diagonal segments. Experimental results show that the
number of available spare cells is increases by 66.5%, while leading to only
2.8% additional total wire length.
Keywords: Engineering
change order, Obstacle-avoiding, Spare cell, Routing algorithm, X-architecture
Title of the Paper: A High-Accuracy
Electronic Pressure Transducer with a Wide Temperature Range and Single
Iteration Temperature Calibration
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Authors:
M. J. Burke
Abstract: This article reports the development of a solid state pressure
transducer for use in the measurement of blood pressure. It is intended to act
as a replacement gauge for the mercury and aneroid manometers used in
conventional sphygmomanometers. It measures pressure in the range 0-300mmHg
(0-40kPa) with a resolution of 1mmHg (0.13kPa) and an accuracy of +1mmHg
(+0.13kPa) which is displayed on a liquid crystal display. It operates from a
9V PP3 battery over a temperature range of -20 to +60oC. It is fully
temperature compensated and can be calibrated in a single temperature cycle.
Keywords: Pressure
Transducer, Electronic Manometer, Blood Pressure Measurement,
Sphygmomanometers, Temperature Compensation
Title of the Paper: DC Motor Behavior
Analysis on Blocking the Wheels on a Railway Traction Vehicle
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Authors:
Ioan Baciu, Dragos Pasculescu, Corina Daniela Cuntan, Anca Iordan
Abstract: In this work are determined the current’s and voltage’s values
absorbed by the d.c. motor from the componency of a 5MVA locomotive in
short-circuit regime. The measures are determined by means of an analyzer of
electric power’s quality on a locomotive from the periodic testing station.
Are determined also the values of the harmonic distorsion factor and of the
current’s and voltage’s harmonics. The acquired data recorded in the
analyzer’s memory are passed afterwards into a computing system that allows
their further analysis.
Keywords: Electric power’s
quality, harmonic distorsion factor, voltage harmonics, current harmonics,
d.c. motor, short-circuit regime
Title of the Paper: A Simple,
Efficient, and EMI-Optimized Solar Array Inverter
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Authors:
K. H. Edelmoser, F. A. Himmelstoss
Abstract: In the field of electrical solar power conversion efficiency is the
most important topic. In common single-phase inverter applications the current
of the solar array shows a remarkable ripple. This entails two significant
disadvantages: Reduced over all efficiency due to dynamic maximum power point
mismatch and reduced lifetime of the panels due to additional component
stress. Furthermore in environments with several solar strings operating in
parallel to reach the goal of a very close MPP operation, a distributed
current source arrangement has to be chosen. The proposed topology discussed
in this paper uses a separated active filter to fulfill the given
requirements: Minimized input current ripple of the cells, string-optimized
maximum power point tracking and optimal power quality of the supplying grid.
The topology presented in this paper shows a remarkable improvement of the
over-all efficiency as well as a significantly enhanced EMC. Consequently, it
is well suited for solar power inverter applications.
Keywords:
Current-Ripple-Reduction, PWM-Inverter, Solar Energy, Filter, Ripple
Cancellation
Issue 10, Volume 9,
October 2010
Title of the Paper: Modeling and
Performance Evaluation of UTB SGOI Devices Scalable to 22 nm Technology Node
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Authors:
Kiran Bailey, K. S. Gurumurthy
Abstract: There is a limit for classical CMOS devices’ scaling. So to keep the
Moore’s law in force,attempts are being made to explore the possibility of
designing newer devices. These attempts are in the direction of optimizing the
design for high performance and low power applications. Silicon- Germanium on
Insulator (SGOI) MOSFET is one such device which has got a bright future. An
Attempt has been made in this paper to design 2D SGOI MOSFET using a
commercial Technology CAD (TCAD) tool. Development of SGOI based Ultra thin
Body (UTB) MOSFETs are proposed in this work. Device Simulations were
performed for various Gate lengths, Body thicknesses, Anti punch doping and Si
cap layer doping. It was found that, for a given body thickness and gate
length, increasing the Silicon cap doping and anti-punch doping, the
transconductance remains unchanged while Ioff, Drain Induced Barrier lowering
(DIBL), Subthreshold slope and threshold voltages show improvement. Also, the
devices with gate lengths 45nm, 32nm and 22nm demonstrate very good
performance such as low leakage currents and good on current that are
comparable to ITRS and hence can be implemented for sub-30 nm gate length
devices. Device doping profiles have been optimized for the 22nm gate length
CMOS devices to obtain minimum leakage and minimum static power dissipation.
The performance of these devices has been evaluated by incorporating them in a
Ring Oscillator and analyzing the circuit for static power dissipation and
delay. The Ring oscillator consists of 3 inverter stages and with each
inverter stage having a lumped capacitance of 6 MOSFETs.
Keywords: UTB MOSFETs,
SGOI, Leakage currents, DIBL, Subthreshold Slope, Ring Oscillator (RO), TCAD
Title of the Paper: Adaptive Nonuniform
Sampling Delta Modulation - Practical Design Studies
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Authors:
Ryszard Golanski, Jacek Kolodziej
Abstract: The method of design the values of the adapted parameters for 1-bit
delta modulators is the subject of the paper. The method involves systems with
adapting both parameters: the quantization step sizes or/and sampling
intervals. The necessary values of the sampling intervals and the step sizes
should be calculated before the modulation procedure starts. All of the data
of the step sizes or/and time intervals are written into the Lookup Tables.
Block diagram of the ANS-DM delta modulator based on the Lookup Tables is
explained. Main parts of the article are devoted to the analytical
relationships on the basis of which step sizes and sampling intervals can be
calculated. These formulas have been used in the program SYMMOD to computation
particular values of the step sizes and sampling intervals. Two parameters
adaptation in the delta modulation makes the modulator and it’s algorithm more
complicated but decreases considerably the required number of sampling
intervals and step sizes thus improving the quality of conversion (SNR) in
relation to the solutions with only one parameter adaptation.
Keywords: Adaptive delta
modulation, non-uniform sampling, Lookup Table, Jayant’s algorithm, dynamic
range Lambert’s function
Title of the Paper: Switching Power
Supply Unit for an Autonomous Monitoring System
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Authors:
Pospisilik Martin, Adamek Milan
Abstract: There is a project of Autonomous monitoring system being solved at
Tomas Bata University in Zlin. Within the framework of this project a small
airship driven by ultrasonic detectors is being developed. This airship shall
be capable of independent operation in an enclosed hall, bearing a camera or
another monitoring system. There are several voltages needed to power the
circuits of the airship. To ensure their feeding from a Li-Pol battery, a
small and lightweight power supply has been designed. In this article, aspects
of designing such power supply unit are analysed. Some attention is also
devoted to the wider aspects of using the airships, mainly their advantages of
low power consumption, and to the circumstances of employing the developed
circuits.
Keywords: Airship, power
supply, SMD, accumulator, propeller, monitoring
Title of the Paper: Meteorological
Parameters Effects on Solar Energy Power Generation
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Authors:
Safak Saglam
Abstract: As Turkey lies near the sunny belt between 36 and 42?N latitudes,
most of the locations in Turkey receive abundant solar energy. The yearly
average solar radiation is 3.6 kWh/m2 day, and the total yearly radiation
period is approximately 2610 h. Meteorological data such as solar radiation,
ambient temperature, relative humidity, wind speed, air pressure and sunshine
duration are accepted as dependable and widely variable renewable energy
resources. These data play a very important role in photovoltaic systems. In
this study, permanent resistive load directly fed from photovoltaic panel
which produce DC electrical energy. Experiments were done during 23 month
period from 2008 to 2010. Permanent resistive load currents and voltages
measured with power analyzer continuously during the day. At the same time
meteorological parameters like outdoor temperature, air pressure, humidity,
wind speed and solar radiation etc. measured and recorded with digital weather
station. These measurement results compared with the graphics at the same time
bases. Photovoltaic panel output power calculated with current and voltage
measurements. A mathematical equation found with curve fitting method from
power graphics to examine dependencies for meteorological parameters. Thus
correlation between photovoltaic performance and meteorological conditions is
examined for Istanbul-Goztepe.
Keywords: Meteorological
Parameters, Electrical Energy, Photovoltaic System, D.C. Loads, Energy
Consumption
Title of the Paper: High
Frequency Stability Semiconductor Laser Sources at 760 nm Wavelength
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Authors:
Bretislav Mikel, Zdenek Buchta, Josef Lazar, Ondrej Cip
Abstract: Measurement with nanometer resolution is required for the next
advance in nanotechnology. Especially the non contacting methods of
measurement are very .promising. We present the set-up of the laser
interferometer with nanometer resolution. We developed three types of laser
sources especially for using in laser interferometry and absolute laser
interferometry. The standard He-Ne laser source for conventional laser
interferometry techniques can be replaced by one of these tree types of laser
sources. We used Vertical Surface Emitting Laser (VCSEL) and Distributed
Feed-Back (DFB) laser diodes to design these laser sources. For these laser
diodes we developed several methods to improvement their wavelength stability
and tunability by fiber Bragg gratings (FBGs). We developed simulation method
to calculation of arbitrary fiber grating (apodized, chirp etc.) with high
precision by combination of methods based on layered dielectric media (LDM)
and transfer matrix. On the basis of our simulations and measurements of the
commercially available fiber gratings we designed a special 100 mm long fiber
Bragg grating with apodization. We expect the application of the FBG to
improvement of the linewidth and mode-hop free tuning range of semiconductor
lasers at the wavelength 760 nm to increase resolution of fiber laser
interferometer based on these diodes. We built the absolute fiber laser
interferometer with Vertical Cavity Surface Emitting Laser (VCSEL) to easy
employ FBG to stabilize wavelength and control the tuning range. First set up
is presented.
Keywords: Laser
interferometry, Absolute measurement, Tunable laser diodes, DFB laser diode,
VCSEL laser diode
Title of the Paper: Laser
Interferometric Measuring System for Positioning in Nanometrology
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Authors:
Josef Lazar, Ondrej Cip, Martin Cizek, Jan Hrabina, Mojmir Sery, Petr Klapetek
Abstract: In this contribution we present a development of a system for
dimensional nanometrology based on scanning probe microscopy techniques
(primarily atomic force microscopy, AFM) for detection of sample profile
combined with interferometer controlled positioning. The key goal for
introduction of interferometer measurement is not only improvement of
resolution but the direct traceability to the primary etalon of length.
Interferometry compared to a host of other optical length measuring techniques
[1,2,3...] represents the most precise measuring technique available. The
system is being developed to operate at and in cooperation with the Czech
metrology institute for calibration purposes and nanometrology.
Keywords: Nanometrology,
Interferometry, Traceability, Local probe microscopy, Nanopositioning
Issue 11, Volume 9,
November 2010
Title of the Paper: On the Margin
Effects of Commercial Bank Expansion into Securities and Insurance Activities
under the Same Roof: A Mathematical Swap Approach
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Authors:
Jyh-Jiuan Lin,Pai-Chou Huang, Wei-Ming Hung
Abstract: The Gramm-Leach-Bliley Act (GLBA) of 1999 allows commercial bank
expansion into investment banking of securities and insurance activities
without limit in subsidiaries separate from commercial banks. This paper
demonstrates how securities hedging, insurance underwriting, and capital
regulation through the total return swap approach jointly determine the
optimal bank interest margin under the same roof. We find that the bank’s
interest margin and noninterest income are positively related to the bank’s
securities hedging demand, and to the insurance underwriting provision, but
negatively related to the bank capital requirement. We also find that the
results of the bank’s noninterest income follow a similar argument as in the
case of a change in interest margin. The results show that the combined
production of commercial banking expansion into investment banking enhances
the bank’s synergistic gains. In addition, if regulators reduce capital
charges, a commercial bank will have a strong incentive to expand its
investment banking activities. This suggests obvious diversification benefits
from the return to investment banking under the same roof.
Keywords:
Gramm-Leach-Bliley Act, Commercial Banking, Investment Banking, Total Return
Swap
Title of the Paper: Modeling Bank
Interest Margin and Loan Quality under the Troubled Asset Relief Program: An
Option-Pricing Approach
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Authors:
Jyh-Horng Lin, Jyh-Jiuan Lin, Pai-Chou Huang
Abstract: The troubled assets on U.S. banks’ books could grow to as much as $5
trillion, one Goldman Sachs analyst estimates [10]. Will setting up the
Troubled Asset Relief Program (TARP) be good move for bank loan quality? The
answer is yes. In an option-pricing model where the bank’s book value of loans
is above its market price, an increase in loan amount sold, exactly what the
TARP is meant to target, increases the bank’s interest margin. The gap where
carrying value is above market price is shrinking by decreasing the risky
loans held by the bank and thus the bank’s loan portfolio quality is improved.
Keywords: Troubled Asset
Relief Program, Bank Interest Margin, Loan Quality
Title of the Paper: Improving
Ion-Sensitive Field-Effect Transistor Selectivity with Backpropagation Neural
Network
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Authors:
Wan Fazlida Hanim Abdullah,, Masuri Othman, Mohd Alaudin Mohd Ali, Md Shabiul
Islam
Abstract: The ion-sensitive field-effect transistor (ISFET) that is designed
to detect a specific ionic activity is susceptible to interfering ions in
mixed-ion environments causing the sensor to produce deceptive signals. The
objective of this work is to improve the interpretation of ISFET signals in
mixed-ion environments. The focus of the research is relating sensor signal to
the targeted ion concentration by applying supervised neural network as
post-processing stage as a method to overcome low selectivity issues. In this
paper, we acquire ISFET voltage response data in potassium and ammonium
mixed-ion solutions for the training of a multilayer perceptron with
backpropagation algorithm. A constant-voltage constant-current readout
interface circuit is applied to maintain constant bias of the sensor
throughout the data collection process. Primary data from measured
observations was fed to a feed-forward multilayer perceptron trained to
classify levels of ionic concentrations in various levels of mixed-ion
solutions. Accuracy of sensor response interpretation of ionic activity
estimation is compared between with and without neural network post-processing
stage. Neural network performance was also compared for voltage values with
and without pre-processing voltage signals by referencing sensor response in
deionized water. Further improvement of the network was approached by using an
ensemble of similar structures of networks trained with backpropagation
constructed using the bagging algorithm. Results show that neural network fed
with dc voltage response from 4-sensor array is able to improve concentration
estimation by 15% improvement compared to direct estimation based on a look-up
table. Pre-processing the sensor response significantly improves the sensor
signal repeatability correlation factor by 15.5% and reduces mean-square error
by 98.3%, with a typical 20% improvement in output-target regression factor
network performance. Averaging from ensemble system is shown to give a further
5% improvement on the output-target regression factor with consistently stable
ion concentration estimations.
Keywords: Microsensors,
electrochemical devices, MOSFET, sensor array, supervised learning,
selectivity
Title of the Paper: Dynamic Stability
Evaluation for an Electromagnetic Contactor
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Authors:
Chieh-Tsung Chi, Chih-Yu Hung
Abstract: This paper aims at researching the relationship between the dynamic
stability of an electromagnetic contactor (abbreviated as contactor below) and
the magnetic energy stored in the contactor. Explored contactors are served as
an equivalent nonlinear and time-varying inductor. Some basic and important
characteristics of the contactor are theoretically researched and discussed.
Several critical results are found during closing phase and voltage sag events
occurred simply by using the basic definitions of passivity conditions
theorem. By means of magnetic circuit analyzing method, a mathematic model and
its numerical computer program of a contactor are first established in our
laboratory. Therefore, some typical and important experiments such as the
dynamic stability of contactor during the closing process and voltage-sag
events are carried out by using this model. Later, these simulation results
are compared with the experimental results for validating the correctness of
this contactor model too. The final comparing results are in agreement with
well. For purpose of further to know the voltage sensitivity of the
experimental contactor, the CBEMA curves of contactor are used and obtained as
well. Finally, the dynamic stability of the contactor during closing process
and voltage sags is examined in terms of the energy stored through the
simulation process of the contactor. Lots of simulation and experimental
results make sure that the contactor model is correct and proposed dynamic
stability evaluation method is effective.
Keywords: CBEMA curve,
passivity energy, contactor, voltage sag, dynamic stability
Issue 12, Volume 9,
December 2010
Title of the Paper: Study on the
Operation of a Low-Voltage AC Microgrid with Multiple Distributed Generations
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Authors:
Wei-Tzer Huang
Abstract: This paper aims to study the operation of a low-voltage AC microgrid
with multiple distributed generations (DGs). First of all, a 400 V low-voltage
AC microgrid integrated with a 30 kW microturbine generator, a 13 kW
photovoltaic generation system, a 10 kW fuel cell generation system, and a 10
kVA wind turbine generator was employed as the sample system. Next, a
sequential three-phase power-flow program that developed by the implicit ZBUS
Gauss method was derived in this paper. Finally, the daily transformer
loadings, voltage/line flow profiles, and system losses of the proposed
microgrid were analyzed and discussed by the developed sequential three-phase
power-flow program. The outcomes of this paper are helpful for researchers to
realize the operation characteristics of AC low-voltage microgrids.
Keywords: Microgrids,
Distributed Generators, Steady-State Analysis, Three-Phase Power-Flow,
Distribution Systems, Line Flow
Title of the Paper: A Standard Cell
Based Synchronous Dual-Bit Adder with Embedded Carry Look-Ahead
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Authors:
Padmanabhan Balasubramanian, Krishnamachar Prasad, Nikos E. Mastorakis
Abstract: A novel synchronous dual-bit adder design, realized using the
elements of commercial standard cell libraries is presented in this article.
The adder embeds two-bit carry look-ahead generator functionality and is
realized using simple and compound gates of the standard cell library. The
performance of the proposed dualbit adder design is evaluated and compared
vis-a-vis the conventional full adder (implemented using two half adder
blocks) and the library’s full adder element, when performing 32-bit addition
on the basis of the fundamental carry propagate adder topology. Based on
experimentations targeting the best case process corner of the high-speed
130nm UMC CMOS cell library and the highest speed corner of the inherently
power optimized 65nm STMicroelectronics CMOS standard cell library, it has
been found that the proposed adder module is effective in achieving
significant performance gains even in comparison with the commercial library
based adder whilst facilitating reduced energy-delay product.
Keywords: Adder,
High-speed, Low power, PDP, EDP, Standard cells, Semi-custom design style
Title of the Paper: A Software Solution
for Mechanical Change Measurement through Virtual Instrumentation
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Authors:
Nicolae Patrascoiu, Aron Poanta, Adrian Tomus, Bogdan Sochirca
Abstract: This paper presents a software solution for implementing a method to
measure a displacement and angular speed for a mobile that is moving in a
linear or circular direction. In order to achieve this, we determine a
function for sensing the direction of movement and also we propose the
algorithm through which is made the measurement. In order to implement this we
use a instrument built in LabVIEW. By this algorithm is possible to use a data
acquisition boards for general use, such as PCI-6024E, which has no inputs for
quadrature signals with a quadrature encoder, such as E6A2-CW5C (Omron) or
HEDS – 5500 (Avago Technologies) that generates this type of signals.
Keywords: Quadrature
encoder, data acquisition board, algorithm, virtual instrument, measurement
Title of the Paper: Pulse Generator
Monocycle Gaussian for UWB Applications
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Authors:
Mohamed Dhieb, Mongi Lahiani, Hamadi Ghariani
Abstract: This paper focuses on the study and design of a simple MOS generator
circuit which provides the first derivative of the Gaussian pulse from input
rectangular signal. To generate wavelets required in an ultra-wideband (UWB)
impulse radio, the first derivative of the Gaussian function is approximated
by combining four hyperbolic tangent functions (tanh). Afterwards, four
differential pairs are used. The output generator circuit is ultra short
monocycle pulses about 244 ps width alternately in phase and in opposition of
phase. The generated width pulse can be adjusted by changing the rise and fall
time of the input signal. Simulations show that a good approximation of this
waveform is possible while using integrated coefficients. A MOS transistor
circuit implementation is presented and its simulation results are shown.
Comparisons between theoretical and simulation tests are detailed in order to
validate the design and the good functioning of the complete structure. .
Furthermore, the 2.5 V voltages supply, relative to the chosen MOS 0.35µm
technologies (AMS foundry), allows the reduction of the system power
consumption.
Keywords: Transfer
function, Hyperbolic tangent, MOS transistors differential pair, Monocycle
pulses, Ring oscillator
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