Abstract: This paper presents a fault-tolerant implementation for
adder schemes using the dual duplication code. To prove the
efficiency of the proposed method, the circuit is simulated in double
pass transistor CMOS 32nm technology and some transient faults are
voluntary injected in the Layout of the circuit. This fully differential
implementation requires only 20 transistors which mean that the
proposed design involves 28.57% saving in transistor count
compared to standard CMOS technology.
Abstract: The paper focuses on the distance laboratory
organisation for training the electrical engineering staff and students
in the fields of electrical drive and power electronics. To support
online knowledge acquisition and professional enhancement, new
challenges in remote education based on an active learning approach
with self-assessment have been emerged by the authors. Following
the literature review and explanation of the improved assessment
methodology, the concept and technological basis of the labs
arrangement are presented. To decrease the gap between the distance
study of the up-to-date equipment and other educational activities in
electrical engineering, the improvements in the following-up the
learners’ progress and feedback composition are introduced. An
authoring methodology that helps to personalise knowledge
acquisition and enlarge Web-based possibilities is described.
Educational management based on self-assessment is discussed.
Abstract: The field of instrumentation electronics is undergoing
an explosive growth, due to its wide range of applications. The
proliferation of electrical devices in a close working proximity can
negatively influence each other’s performance. The degradation in
the performance is due to electromagnetic interference (EMI). This paper investigates the negative effects of electromagnetic
interference originating in the General Purpose Interface Bus (GPIB)
control-network of the AC-DC transfer measurement system.
Remedial measures of reducing measurement errors and failure of
range of industrial devices due to EMI have been explored. The ACDC
transfer measurement system was analysed for the commonmode
(CM) EMI effects. Further investigation of coupling path as
well as much accurate identification of noise propagation mechanism
has been outlined. To prevent the occurrence of common-mode
(ground loops) which was identified between the GPIB system
control circuit and the measurement circuit, a microcontroller-driven
GPIB switching isolator device was designed, prototyped,
programmed and validated. This mitigation technique has been
explored to reduce EMI effectively.
Abstract: This study aims to establish function point process
based on stochastic distribution. In order to demonstrate effectiveness
of the study we present a case study that it applies suggested method
on an automotive electrical and electronics system software
development based on Monte Carlo Simulation. It is expected that the
result of this paper is used as guidance for establishing function point
process in organizations and tools for helping project managers make
decisions correctly.
Abstract: Microcantilevers are the basic MEMS devices, which
can be used as sensors, actuators and electronics can be easily built
into them. The detection principle of microcantilever sensors is based
on the measurement of change in cantilever deflection or change in its
resonance frequency. The objective of this work is to explore the
analogies between mechanical and electrical equivalent of
microcantilever beams. Normally scientists and engineers working in
MEMS use expensive software like CoventorWare, IntelliSuite,
ANSYS/Multiphysics etc. This paper indicates the need of developing
electrical equivalent of the MEMS structure and with that, one can
have a better insight on important parameters, and their interrelation of
the MEMS structure. In this work, considering the mechanical model
of microcantilever, equivalent electrical circuit is drawn and using
force-voltage analogy, it is analyzed with circuit simulation software.
By doing so, one can gain access to powerful set of intellectual tools
that have been developed for understanding electrical circuits Later
the analysis is performed using ANSYS/Multiphysics - software based
on finite element method (FEM). It is observed that both mechanical
and electrical domain results for a rectangular microcantlevers are in
agreement with each other.
Abstract: The power electronic components within Electric Vehicles (EV) need to operate in several important modes. Some modes directly influence safety, while others influence vehicle performance. Given the variety of functions and operational modes required of the power electronics, it needs to meet efficiency requirements to minimize power losses. Another challenge in the control and construction of such systems is the ability to support bidirectional power flow. This paper considers the construction, operation, and feasibility of available converters for electric vehicles with feasible configurations of electrical buses and loads. This paper describes logic and control signals for the converters for different operations conditions based on the efficiency and energy usage bases.
Abstract: The subject of this paper is to review, comparative
analysis and simulation of selected components of power electronic
systems (PES), consistent with the concept of a more electric aircraft
(MEA). Comparative analysis and simulation in software
environment MATLAB / Simulink were carried out on the base of a
group of representatives of civil aircraft (B-787, A-380) and military
(F-22 Raptor, F-35) in the context of multi-pulse converters used in
them (6- and 12-pulse, and 18- and 24-pulse), which are key
components of high-tech electronics on-board power systems of
autonomous power systems (ASE) of modern aircraft (airplanes of
the future).
Abstract: In this study, it has been studied to determine the
relationship between business performance and strategic flexibility,
which is defined to be the strategic choice that provides the ability of
rapidly responding the changes of the dynamic environment of the
companies, for having competitive advantages. In this context a field
study has been conducted over 56 companies, which are active in
informatics and electronics sectors in TEKNOKENT. As a result of
the study it has been determined that; strategic flexibility has an
effect on business performance and there is a positive and
statistically significant relationship between strategic flexibility and
business performance.
Abstract: Si-Ge solid solutions (bulk poly- and mono-crystalline
samples, thin films) are characterized by high perspectives for
application in semiconductor devices, in particular, optoelectronics
and microelectronics. From this point of view, complex studying of
structural state of the defects and structural-sensitive physical
properties of Si-Ge solid solutions depending on the contents of Si
and Ge components is very important. Present work deals with the
investigations of microstructure, microhardness, internal friction and
shear modulus of Si1-xGex(x≤0,02) bulk monocrystals conducted at
room temperature. Si-Ge bulk crystals were obtained by Czochralski
method in [111] crystallographic direction. Investigated
monocrystalline Si-Ge samples are characterized by p-type
conductivity and carriers’ concentration 5.1014-1.1015cm-3.
Microhardness was studied on Dynamic Ultra Micro hardness Tester
DUH-201S with Berkovich indenter. Investigate samples are characterized with 0,5x0,5x(10-15)mm3
sizes, oriented along [111] direction at torsion oscillations ≈1Hz,
multistage changing of internal friction and shear modulus has been
revealed in an interval of strain amplitude of 10-5-5.10-3. Critical
values of strain amplitude have been determined at which hysteretic
changes of inelastic characteristics and microplasticity are observed. The critical strain amplitude and elasticity limit values are also
determined. Dynamic mechanical characteristics decreasing trend is
shown with increasing Ge content in Si-Ge solid solutions. Observed
changes are discussed from the point of view of interaction of various
dislocations with point defects and their complexes in a real structure
of Si-Ge solid solutions.
Abstract: This paper describes a sliding mode controller for
autonomous underwater vehicles (AUVs). The dynamic of AUV
model is highly nonlinear because of many factors, such as
hydrodynamic drag, damping, and lift forces, Coriolis and centripetal
forces, gravity and buoyancy forces, as well as forces from thruster.
To address these difficulties, a nonlinear sliding mode controller is
designed to approximate the nonlinear dynamics of AUV and
improve trajectory tracking. Moreover, the proposed controller can
profoundly attenuate the effects of uncertainties and external
disturbances in the closed-loop system. Using the Lyapunov theory
the boundedness of AUV tracking errors and the stability of the
proposed control system are also guaranteed. Numerical simulation
studies of an AUV are included to illustrate the effectiveness of the
presented approach.
Abstract: Conductivity properties of DNA molecule is
investigated in a simple, but chemically specific approach that is
intimately related to the Su-Schrieffer-Heeger (SSH) model. This
model is a tight-binding linear nanoscale chain. We have tried to
study the electrical current flowing in DNA and investigated the
characteristic I-V diagram. As a result, It is shown that there are the
(quasi-) ohmic areas in I-V diagram. On the other hand, the regions
with a negative differential resistance (NDR) are detectable in
diagram.
Abstract: Aluminium matrix composites with alumina
reinforcements give superior mechanical & physical properties. Their
applications in several fields like automobile, aerospace, defense,
sports, electronics, bio-medical and other industrial purposes are
becoming essential for the last several decades. In the present work,
fabrication of hybrid composite was done by Stir casting technique
using Al 6061 as a matrix with alumina and silicon carbide (SiC) as
reinforcement materials. The weight percentage of alumina is varied
from 2 to 4% and the silicon carbide weight percentage is maintained
constant at 2%. Hardness and wear tests are performed in the as cast
and heat treated conditions. Age hardening treatment was performed
on the specimen with solutionizing at 550°C, aging at two
temperatures (150 and 200°C) for different time durations. Hardness
distribution curves are drawn and peak hardness values are recorded.
Hardness increase was very sensitive with respect to the decrease in
aging temperature. There was an improvement in wear resistance of
the peak aged material when aged at lower temperature. Also
increase in weight percent of alumina, increases wear resistance at
lower temperature but opposite behavior was seen when aged at
higher temperature.
Abstract: This paper presents the design and characterization of
analog readout interface circuits for ion sensitive field effect
transistor (ISFET) and ion selective electrode (ISE) based sensor.
These interface circuits are implemented using MIMOS’s 0.35um
CMOS technology and experimentally characterized under 24-leads
QFN package. The characterization evaluates the circuit’s
functionality, output sensitivity and output linearity. Commercial
sensors for both ISFET and ISE are employed together with glass
reference electrode during testing. The test result shows that the
designed interface circuits manage to readout signals produced by
both sensors with measured sensitivity of ISFET and ISE sensor are
54mV/pH and 62mV/decade, respectively. The characterized output
linearity for both circuits achieves above 0.999 Rsquare. The readout
also has demonstrated reliable operation by passing all qualifications
in reliability test plan.
Abstract: By textile science incorporating with electronic
industry, developed textile products start to take part in different
areas such as industry, military, space, medical etc. for health,
protection, defense, communication and automation. Electronic
textiles (e-textiles) are fabrics that contain electronics and
interconnections with them. In this study, two types of base yarns
(cotton and acrylic) and three types of conductive steel yarns with
different linear resistance values (14Ω/m, 30Ω/m, 70Ω/m) were used
to investigate the effect of base yarn type and linear resistance of
conductive yarns on thermal behavior of e-textile structures. Thermal
behavior of samples was examined by thermal camera.
Abstract: This study introduces two types of self-oscillating
circuits that are frequently found in power electronics applications.
Special effort is made to relate the circuits to the analogous mechanical
systems of some important scientific inventions: Galileo’s pendulum
clock and Coulomb’s friction model. A little touch of related history
and philosophy of science will hopefully encourage curiosity, advance
the understanding of self-oscillating systems and satisfy the aspiration
of some students for scientific literacy. Finally, the two self-oscillating
circuits are applied to design a simple class-D audio amplifier.
Abstract: Meeting the growth in demand for digital services
such as social media, telecommunications, and business and cloud
services requires large scale data centres, which has led to an increase
in their end use energy demand. Generally, over 30% of data centre
power is consumed by the necessary cooling overhead. Thus energy
can be reduced by improving the cooling efficiency. Air and liquid
can both be used as cooling media for the data centre. Traditional
data centre cooling systems use air, however liquid is recognised as a
promising method that can handle the more densely packed data
centres. Liquid cooling can be classified into three methods; rack heat
exchanger, on-chip heat exchanger and full immersion of the
microelectronics. This study quantifies the improvements of heat
transfer specifically for the case of immersed microelectronics by
varying the CPU and heat sink location. Immersion of the server is
achieved by filling the gap between the microelectronics and a water
jacket with a dielectric liquid which convects the heat from the CPU
to the water jacket on the opposite side. Heat transfer is governed by
two physical mechanisms, which is natural convection for the fixed
enclosure filled with dielectric liquid and forced convection for the
water that is pumped through the water jacket. The model in this
study is validated with published numerical and experimental work
and shows good agreement with previous work. The results show that
the heat transfer performance and Nusselt number (Nu) is improved
by 89% by placing the CPU and heat sink on the bottom of the
microelectronics enclosure.
Abstract: The increasing demand of gallium, indium and
rare-earth elements for the production of electronics, e.g. solid
state-lighting, photovoltaics, integrated circuits, and liquid crystal
displays, will exceed the world-wide supply according to current
forecasts. Recycling systems to reclaim these materials are not yet in
place, which challenges the sustainability of these technologies. This
paper proposes a multispectral imaging system as a basis for a vision
based recognition system for valuable components of electronics
waste. Multispectral images intend to enhance the contrast of images
of printed circuit boards (single components, as well as labels) for
further analysis, such as optical character recognition and entire
printed circuit board recognition. The results show, that a higher
contrast is achieved in the near infrared compared to ultraviolett and
visible light.
Abstract: Water contamination by toxic compound is one of the serious environmental problems today. These toxic compounds mostly originated from industrial effluents, agriculture, natural sources and human waste. These studies focus on modification of multiwalled carbon nanotube (MWCNTs) with nanoparticle of calixarene and explore the possibility of using this modification for the remediation of cadmium in water. The nanocomposites were prepared by dissolving calixarene in chloroform solution as solvent, followed by additional multiwalled carbon nanotube (MWCNTs) then sonication process for 3 hour and fabricated the nanocomposites on substrate by spin coating method. Finally, the nanocomposites were tested on cadmium ion (10 mg/ml). The morphology of nanocomposites was investigated by FESEM showing the formation of calixarene on the outer walls of carbon nanotube and cadmium ion also clearly seen from the micrograph. This formation was supported by using energy dispersive x-ray (EDX). The presence of cadmium ions in the films, leads to some changes in the surface potential and Fourier Transform Infrared spectroscopy (FTIR).The nanocomposites MWCNTs-calixarene have potential for development of sensor for pollutant monitoring and nanoelectronics devices applications.
Abstract: The aim of this study was to design and simulate a
particular type of Asynchronous State Machine (ASM), namely a
‘traffic light controller’ (TLC), operated at a frequency of 0.5 Hz.
The design task involved two main stages: firstly, designing a 4-bit
binary counter using J-K flip flops as the timing signal and,
subsequently, attaining the digital logic by deploying ASM design
process. The TLC was designed such that it showed a sequence of
three different colours, i.e. red, yellow and green, corresponding to
set thresholds by deploying the least number of AND, OR and NOT
gates possible. The software Multisim was deployed to design such
circuit and simulate it for circuit troubleshooting in order for it to
display the output sequence of the three different colours on the
traffic light in the correct order. A clock signal, an asynchronous 4-
bit binary counter that was designed through the use of J-K flip flops
along with an ASM were used to complete this sequence, which was
programmed to be repeated indefinitely. Eventually, the circuit was
debugged and optimized, thus displaying the correct waveforms of
the three outputs through the logic analyser. However, hazards
occurred when the frequency was increased to 10 MHz. This was
attributed to delays in the feedback being too high.
Abstract: Over the last few decades, oilfield service rolling
equipment has significantly increased in weight, primarily because of
emissions regulations, which require larger/heavier engines, larger
cooling systems, and emissions after-treatment systems, in some
cases, etc. Larger engines cause more vibration and shock loads,
leading to failure of electronics and control systems.
If the vibrating frequency of the engine matches the system
frequency, high resonance is observed on structural parts and mounts.
One such existing automated control equipment system comprising
wire rope mounts used for mounting computers was designed
approximately 12 years ago. This includes the use of an industrialgrade
computer to control the system operation. The original
computer had a smaller, lighter enclosure. After a few years, a newer
computer version was introduced, which was 10 lbm heavier. Some
failures of internal computer parts have been documented for cases in
which the old mounts were used. Because of the added weight, there
is a possibility of having the two brackets impact each other under
off-road conditions, which causes a high shock input to the computer
parts. This added failure mode requires validating the existing mount
design to suit the new heavy-weight computer.
This paper discusses the modal finite element method (FEM)
analysis and experimental modal analysis conducted to study the
effects of vibration on the wire rope mounts and the computer. The
existing mount was modelled in ANSYS software, and resultant
mode shapes and frequencies were obtained. The experimental modal
analysis was conducted, and actual frequency responses were
observed and recorded.
Results clearly revealed that at resonance frequency, the brackets
were colliding and potentially causing damage to computer parts. To
solve this issue, spring mounts of different stiffness were modeled in
ANSYS software, and the resonant frequency was determined.
Increasing the stiffness of the system increased the resonant
frequency zone away from the frequency window at which the engine
showed heavy vibrations or resonance. After multiple iterations in
ANSYS software, the stiffness of the spring mount was finalized,
which was again experimentally validated.