Abstract: This paper presents an optimal design of poly-phase induction motor using Quadratic Interpolation based Particle Swarm Optimization (QI-PSO). The optimization algorithm considers the efficiency, starting torque and temperature rise as objective function (which are considered separately) and ten performance related items including harmonic current as constraints. The QI-PSO algorithm was implemented on a test motor and the results are compared with the Simulated Annealing (SA) technique, Standard Particle Swarm Optimization (SPSO), and normal design. Some benchmark problems are used for validating QI-PSO. From the test results QI-PSO gave better results and more suitable to motor-s design optimization. Cµ code is used for implementing entire algorithms.
Abstract: Nowadays wireless technology plays an important
role in public and personal communication. However, the growth of
wireless networking has confused the traditional boundaries between
trusted and untrusted networks. Wireless networks are subject to a
variety of threats and attacks at present. An attacker has the ability to
listen to all network traffic which becoming a potential intrusion.
Intrusion of any kind may lead to a chaotic condition. In addition,
improperly configured access points also contribute the risk to
wireless network. To overcome this issue, a security solution that
includes an intrusion detection and prevention system need to be
implemented. In this paper, first the security drawbacks of wireless
network will be analyzed then investigate the characteristics and also
the limitations on current wireless intrusion detection and prevention
system. Finally, the requirement of next wireless intrusion prevention
system will be identified including some key issues which should be
focused on in the future to overcomes those limitations.
Abstract: Impinging jets are used in various industrial areas as a cooling and drying technique. The current research is concerned with the means of improving the heat transfer for configurations with a minimum distance of the nozzle to the impingement surface. The impingement heat transfer is described using numerical methods over a wide range of parameters for an array of planar jets. These parameters include varying jet flow speed, width of nozzle, distance of nozzle, angle of the jet flow, velocity and geometry of the impingement surface. Normal pressure and shear stress are computed as additional parameters. Using dimensionless characteristic numbers the parameters and the results are correlated to gain generalized equations. The results demonstrate the effect of the investigated parameters on the flow.
Abstract: Automatic reading of handwritten cheque is a computationally
complex process and it plays an important role in financial
risk management. Machine vision and learning provide a viable
solution to this problem. Research effort has mostly been focused
on recognizing diverse pitches of cheques and demand drafts with an
identical outline. However most of these methods employ templatematching
to localize the pitches and such schemes could potentially
fail when applied to different types of outline maintained by the
bank. In this paper, the so-called outline problem is resolved by
a cheque information tree (CIT), which generalizes the localizing
method to extract active-region-of-entities. In addition, the weight
based density plot (WBDP) is performed to isolate text entities and
read complete pitches. Recognition is based on texture features using
neural classifiers. Legal amount is subsequently recognized by both
texture and perceptual features. A post-processing phase is invoked
to detect the incorrect readings by Type-2 grammar using the Turing
machine. The performance of the proposed system was evaluated
using cheque and demand drafts of 22 different banks. The test data
consists of a collection of 1540 leafs obtained from 10 different
account holders from each bank. Results show that this approach
can easily be deployed without significant design amendments.
Abstract: Thermal load calculations have been performed for
multi-layered walls that are composed of three different parts; a
common (sand and cement) plaster, and two types of locally
produced soft and hard bricks. The masonry construction of these
layered walls was based on concrete-backed stone masonry made of
limestone bricks joined by mortar. These multilayered walls are
forming the outer walls of the building envelope of a typical Libyan
house. Based on the periodic seasonal weather conditions, within the
Libyan cost region during summer and winter, measured thermal
conductivity values were used to implement such seasonal variation
of heat flow and the temperature variations through the walls. The
experimental measured thermal conductivity values were obtained
using the Hot Disk technique. The estimation of the thermal
resistance of the wall layers ( R-values) is based on measurements
and calculations. The numerical calculations were done using a
simplified analytical model that considers two different wall
constructions which are characteristics of such houses. According to
the obtained results, the R-values were quite low and therefore,
several suggestions have been proposed to improve the thermal
loading performance that will lead to a reasonable human comfort
and reduce energy consumption.
Abstract: Analytical seismic response of multi-story building
supported on base isolation system is investigated under real
earthquake motion. The superstructure is idealized as a shear type
flexible building with lateral degree-of-freedom at each floor. The
force-deformation behaviour of the isolation system is modelled by
the bi-linear behaviour which can be effectively used to model all
isolation systems in practice. The governing equations of motion of
the isolated structural system are derived. The response of the system
is obtained numerically by step-by-method under three real recorded
earthquake motions and pulse motions associated in the near-fault
earthquake motion. The variation of the top floor acceleration, interstory
drift, base shear and bearing displacement of the isolated
building is studied under different initial stiffness of the bi-linear
isolation system. It was observed that the high initial stiffness of the
isolation system excites higher modes in base-isolated structure and
generate floor accelerations and story drift. Such behaviour of the
base-isolated building especially supported on sliding type of
isolation systems can be detrimental to sensitive equipment installed
in the building. On the other hand, the bearing displacement and base
shear found to reduce marginally with the increase of the initial
stiffness of the initial stiffness of the isolation system. Further, the
above behaviour of the base-isolated building was observed for
different parameters of the bearing (i.e. post-yield stiffness and
characteristic strength) and earthquake motions (i.e. real time history
as well as pulse type motion).
Abstract: The present energy situation and the concerns
about global warming has stimulated active research interest
in non-petroleum, carbon free compounds and non-polluting
fuels, particularly for transportation, power generation, and
agricultural sectors. Environmental concerns and limited
amount of petroleum fuels have caused interests in the
development of alternative fuels for internal combustion (IC)
engines. The petroleum crude reserves however, are declining
and consumption of transport fuels particularly in the
developing countries is increasing at high rates. Severe
shortage of liquid fuels derived from petroleum may be faced
in the second half of this century. Recently more and more
stringent environmental regulations being enacted in the USA
and Europe have led to the research and development
activities on clean alternative fuels. Among the gaseous fuels
hydrogen is considered to be one of the clean alternative fuel.
Hydrogen is an interesting candidate for future internal
combustion engine based power trains. In this experimental
investigation, the performance and combustion analysis were
carried out on a direct injection (DI) diesel engine using
hydrogen with diesel following the TMI(Time Manifold
Injection) technique at different injection timings of 10
degree,45 degree and 80 degree ATDC using an electronic
control unit (ECU) and injection durations were controlled.
Further, the tests have been carried out at a constant speed of
1500rpm at different load conditions and it can be observed
that brake thermal efficiency increases with increase in load
conditions with a maximum gain of 15% at full load
conditions during all injection strategies of hydrogen. It was
also observed that with the increase in hydrogen energy share
BSEC started reducing and it reduced to a maximum of 9% as
compared to baseline diesel at 10deg ATDC injection during
maximum injection proving the exceptional combustion
properties of hydrogen.
Abstract: Graduate attributes have received increasing attention
over recent years as universities incorporate these attributes into the
curriculum. Graduates who have adequate technical knowledge only
are not sufficiently equipped to compete effectively in the work
place; they also need non disciplinary skills ie, graduate attributes.
The purpose of this paper is to investigate the impact of an eportfolio
in a technical communication course to enhance engineering
students- graduate attributes: namely, learning of communication,
critical thinking and problem solving and teamwork skills. Two
questionnaires were used to elicit information from the students: one
on their preferred and the other on the actual learning process. In
addition, student perceptions of the use of eportfolio as a learning
tool were investigated. Preliminary findings showed that most of the
students- expectations have been met with their actual learning. This
indicated that eportfolio has the potential as a tool to enhance
students- graduate attributes.
Abstract: In this paper, we will present an architecture for the
implementation of a real time stereoscopic images correction's
approach. This architecture is parallel and makes use of several
memory blocs in which are memorized pre calculated data relating to
the cameras used for the acquisition of images. The use of reduced
images proves to be essential in the proposed approach; the
suggested architecture must so be able to carry out the real time
reduction of original images.
Abstract: The distressing flood scenarios that occur in
recent years at the surrounding areas of Sarawak River have
left damages of properties and indirectly caused disruptions of
productive activities. This study is meant to reconstruct a 100-year
flood event that took place in this river basin. Sarawak River Subbasin
was chosen and modeled using the one-dimensional
hydrodynamic modeling approach using InfoWorks River Simulation
(RS), in combination with Geographical Information System (GIS).
This produces the hydraulic response of the river and its floodplains
in extreme flooding conditions. With different parameters introduced
to the model, correlations of observed and simulated data are
between 79% – 87%. Using the best calibrated model, flood
mitigation structures are imposed along the sub-basin. Analysis is
done based on the model simulation results. Result shows that the
proposed retention ponds constructed along the sub-basin provide the
most efficient reduction of flood by 34.18%.
Abstract: Many experimental results suggest that more precise spike timing is significant in neural information processing. We construct a self-organization model using the spatiotemporal pat-terns, where Spike-Timing Dependent Plasticity (STDP) tunes the conduction delays between neurons. We show that, for highly syn-chronized inputs, the fluctuation of conduction delays causes globally continuous and locally distributed firing patterns through the self-organization.
Abstract: The necessity of solving multi dimensional
complicated scientific problems beside the necessity of several
objective functions optimization are the most motive reason of born
of artificial intelligence and heuristic methods.
In this paper, we introduce a new method for multiobjective
optimization based on learning automata. In the proposed method,
search space divides into separate hyper-cubes and each cube is
considered as an action. After gathering of all objective functions
with separate weights, the cumulative function is considered as the
fitness function. By the application of all the cubes to the cumulative
function, we calculate the amount of amplification of each action and
the algorithm continues its way to find the best solutions. In this
Method, a lateral memory is used to gather the significant points of
each iteration of the algorithm. Finally, by considering the
domination factor, pareto front is estimated. Results of several
experiments show the effectiveness of this method in comparison
with genetic algorithm based method.
Abstract: In the present paper, we use generalized B-Spline curve in trigonometric form on circular domain, to capture the transcendental nature of circle involute curve and uncertainty characteristic of design. The required involute curve get generated within the given tolerance limit and is useful in gear design.
Abstract: In this paper we propose a new criterion for solving
the problem of channel shortening in multi-carrier systems. In a
discrete multitone receiver, a time-domain equalizer (TEQ) reduces
intersymbol interference (ISI) by shortening the effective duration of
the channel impulse response. Minimum mean square error (MMSE)
method for TEQ does not give satisfactory results. In [1] a new
criterion for partially equalizing severe ISI channels to reduce the
cyclic prefix overhead of the discrete multitone transceiver (DMT),
assuming a fixed transmission bandwidth, is introduced. Due to
specific constrained (unit morm constraint on the target impulse
response (TIR)) in their method, the freedom to choose optimum
vector (TIR) is reduced. Better results can be obtained by avoiding
the unit norm constraint on the target impulse response (TIR). In
this paper we change the cost function proposed in [1] to the cost
function of determining the maximum of a determinant subject to
linear matrix inequality (LMI) and quadratic constraint and solve the
resulting optimization problem. Usefulness of the proposed method
is shown with the help of simulations.
Abstract: Carboneous catalytical methane decomposition is an
attractive process because it produces two valuable products:
hydrogen and carbon. Furthermore, this reaction does not emit any
green house or hazardous gases. In the present study, experiments
were conducted in a thermo gravimetric analyzer using Fluka 05120
as carboneous catalyst to analyze its effectiveness in methane
decomposition. Various temperatures and methane partial pressures
were chosen and carbon mass gain was observed as a function of
time. Results are presented in terms of carbon formation rate,
hydrogen production and catalytical activity. It is observed that there
is linearity in carbon deposition amount by time at lower reaction
temperature (780 °C). On the other hand, it is observed that carbon
and hydrogen formation rates are increased with increasing
temperature. Finally, we observed that the carbon formation rate is
highest at 950 °C within the range of temperatures studied.
Abstract: Mobile devices, which are progressively surrounded
in our everyday life, have created a new paradigm where they
interconnect, interact and collaborate with each other. This network
can be used for flexible and secure coordinated sharing. On the other
hand Grid computing provides dependable, consistent, pervasive, and
inexpensive access to high-end computational capabilities. In this
paper, efforts are made to map the concepts of Grid on Ad-Hoc
networks because both exhibit similar kind of characteristics like
Scalability, Dynamism and Heterogeneity. In this context we
propose “Mobile Ad-Hoc Services Grid – MASGRID".
Abstract: Vehicle which are turning or maneuvering at high speeds
are susceptible to sliding and subsequently deviate from desired path. In
this paper the dynamics governing the Yaw/Roll behavior of a vehicle
has been simulated. Two different simulations have been used one for
the real vehicle, for which a fuzzy controller is designed to increase its
directional stability property. The other simulation is for a hypothetical
vehicle with much higher tire cornering stiffness which is capable of
developing the required lateral forces at the tire-ground patch contact to
attain the desired lateral acceleration for the vehicle to follow the
desired path without slippage. This simulation model is our reference
model.
The logic for keeping the vehicle on the desired track in the cornering
or maneuvering state is to have some braking forces on the inner or
outer tires based on the direction of vehicle deviation from the desired
path. The inputs to our vehicle simulation model is steer angle δ and
vehicle velocity V , and the outputs can be any kinematical parameters
like yaw rate, yaw acceleration, side slip angle, rate of side slip angle
and so on. The proposed fuzzy controller is a feed forward controller.
This controller has two inputs which are steer angle δ and vehicle
velocity V, and the output of the controller is the correcting moment M,
which guides the vehicle back to the desired track. To develop the
membership functions for the controller inputs and output and the fuzzy
rules, the vehicle simulation has been run for 1000 times and the
correcting moment have been determined by trial and error. Results of
the vehicle simulation with fuzzy controller are very promising
and show the vehicle performance is enhanced greatly over the
vehicle without the controller. In fact the vehicle performance
with the controller is very near the performance of the reference
ideal model.
Abstract: In areas of low to moderate seismicity many building contents and equipment are not positively fixed to the floor or tied to adjacent walls. Under seismic induced horizontal vibration, such contents and equipment can suffer from damage by either overturning or impact associated with rocking. This paper focuses on the estimation of shock on typical contents and equipment due to rocking. A simplified analytical model is outlined that can be used to estimate the maximum acceleration on a rocking object given its basic geometric and mechanical properties. The developed model was validated against experimental results. The experimental results revealed that the maximum shock acceleration can be underestimated if the static stiffness of the materials at the interface between the rocking object and floor is used rather than the dynamic stiffness. Excellent agreement between the model and experimental results was found when the dynamic stiffness for the interface material was used, which was found to be generally much higher than corresponding static stiffness under different investigated boundary conditions of the cushion. The proposed model can be a beneficial tool in performing a rapid assessment of shock sensitive components considered for possible seismic rectification.
Abstract: This paper provides the design steps of a robust Linear
Matrix Inequality (LMI) based iterative multivariable PID controller
whose duty is to drive a sample power system that comprises a
synchronous generator connected to a large network via a step-up
transformer and a transmission line. The generator is equipped with
two control-loops, namely, the speed/power (governor) and voltage
(exciter). Both loops are lumped in one where the error in the
terminal voltage and output active power represent the controller
inputs and the generator-exciter voltage and governor-valve position
represent its outputs. Multivariable PID is considered here because of
its wide use in the industry, simple structure and easy
implementation. It is also preferred in plants of higher order that
cannot be reduced to lower ones. To improve its robustness to
variation in the controlled variables, H∞-norm of the system transfer
function is used. To show the effectiveness of the controller, divers
tests, namely, step/tracking in the controlled variables, and variation
in plant parameters, are applied. A comparative study between the
proposed controller and a robust H∞ LMI-based output feedback is
given by its robustness to disturbance rejection. From the simulation
results, the iterative multivariable PID shows superiority.
Abstract: The paper provides a literature review of the STEPNC
compliant research around the world. The first part of this paper
focuses on projects based on STEP compliance followed by research
and development in this area based on machining operations. Review
the literature relating to relevant STEP standards and application in
the area of turning centers. This research will review the various
research work, carried out from the evolution of STEP-NC of the
CNC manufacturing activities. The paper concludes with discussion
of the applications in this particular area.