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Editorial
Board
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ISSN:
1998-0140
FORMAT: Format (.doc) or
Format (LaTeX)
Year 2009
All papers of the journal were peer reviewed by two
independent reviewers. Acceptance was granted when both
reviewers' recommendations were positive.
Previous Volumes: 2007
2008
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Paper
Title, Authors, Abstract (Issue 1, Volume 3, 2009) |
Pages |
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Numerical Simulation of
Indonesian Tsunami 2004 at Penang Island in
Peninsular Malaysia Using a Nested Grid Model
Md. Fazlul Karim, Ahmad Izani M Ismail, Mohammed
Ashaque Meah
Abstract: Nested grid modelling
techniques are increasingly being recognized as
methodologies to aid in multiscale modelling of a
variety of atmospheric and oceanic phenomena. A
nested grid model with a fine resolution is used to
simulate the Indonesian tsunami of 2004 along the
coastal belt of Penang Island. The basic primitive
model is depth averaged shallow water equations. A
fine mesh numerical scheme for the Peninsular
Malaysia covering the region between 5?10/ to 5?35/N
and 100? to 100?30/E to record fine orographical
detail of the region of Penang Island has been
nested into a coarse mesh scheme covering the region
approximately between 2° N to 14° N and 91° E to
100.5° E which includes the source region of the
Indonesian tsunami of 2004. The nesting is
accomplished using a scheme Arakawa C staggered grid
arrangement. The solutions are obtained for two
categories: (a) coarse mesh solution, and (b) nested
solution. A nested model is employed in which a
coarse grid model is used to supply the open
boundary conditions for a finer grid. The major
features of the event 2004 along Penang have been
successfully simulated by the nested model.
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1-8 |
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FCM & FPCM Algorithm Based
on Unsupervised Mahalanobis Distances with Better
Initial Values and Separable Criterion
Jeng-Ming Yih, Yuan-Horng Lin, Hsiang-Chuan Liu
Abstract: The fuzzy partition
clustering algorithms are most based on Euclidean
distance function, which can only be used to detect
spherical structural clusters. Gustafson-Kessel (GK)
clustering algorithm and Gath-Geva (GG) clustering
algorithm, were developed to detect non-spherical
structural clusters, but both of them based on
semi-supervised Mahalanobis distance needed
additional prior information. An improved Fuzzy
CMean algorithm based on unsupervised Mahalanobis
distance, FCM-M, was proposed by our previous work,
but it didn’t consider the relationships between
cluster centers in the objective function. In this
paper, we proposed an improved Fuzzy C-Mean
algorithm, FCM-MS, which is not only based on
unsupervised Mahalanobis distance, but also
considering the relationships between cluster
centers, and the relationships between the center of
all points and the cluster centers in the objective
function, the singular and the initial values
problems were also solved. Two real data sets was
applied to prove that the performance of the FCMMS
algorithm gave more accurate clustering results than
the FCM and FCM-M methods, and the ratio method
which is proposed by us is the better of the two
methods for selecting the initial values.
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9-18 |
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The Transmission Model of
P.falciparum and P.Vivax Malaria between Thai and
Burmese
P. Pongsumpun, I. M. Tang
Abstract: The transmission of
Plasmodium falciparum and Plasmodium vivax malaria
of Thais and Burmese is studied through a
mathematical model. The population is separated into
two groups, Thai and Burmese. Each population is
divided into susceptible and infectious subclasses.
The loss of immunity by individuals in the
infectious class causes them to move back into the
susceptible class. Standard dynamical method is used
to analyze the behavior of the model. Two stable
equilibrium states, a disease free state and an
epidemic state are found to be possible in each
population. A disease free equilibrium state in the
Thai population occurs when there are no infected
Burmese entering into the community. When there are
infected Burmese enters into the Thai community, the
epidemic state can occur. It is found that the
disease free state is stable when the threshold
number R0 is less than one. The epidemic state is
stable when (where these threshold numbers are for
the individual populations) are greater than one.
The numerical simulations of our model illustrate
what the results would be for our theoretical model.
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19-26 |
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The Influence of Noise
Kurtosis on the Dynamics of a Harmonic Oscillator
with Fluctuating Frequency
Katrin Laas, Romi Mankin, Astrid Rekker
Abstract: The influence of noise
kurtosis on underdamped motion of a harmonic
oscillator with fluctuating frequency subjected to
an external periodic force and an additive thermal
noise is considered. The colored fluctuations of the
oscillator frequency are modeled as a trichotomous
noise. It is established that the spectral
amplification and variance of the output signal
exhibits a nonmonotonic dependence on the noise
kurtosis, thus demonstrating the phenomenon of noise
kurtosis controlled stochastic resonance. Some
unexpected effects such as hypersensitive response
of spectral amplification to small variations of
noise amplitude, encountered in the case of a large
kurtosis of colored noise are also discussed.
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27-36 |
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Computer-Aided Simulation on
the Reversing Operation of the Two-Phase Induction
Machine
Alecsandru Simion, Leonard Livadaru, Dorin Lucache
Abstract: The paper presents a new
mathematical model of the two-phase induction
machine, called "in total fluxes", which is very
appropriate for the study of the reversing regime.
The equations of the model use as main quantities
the rotation angle and the total fluxes of the
windings and exclude the rotation speed, which now
become a secondary quantity that can be calculated
from rotation angle expression. On the basis of this
model, the computer simulation looks into the
behavior of a two-phase induction servomotor with
low inertia when the supply voltages of the two
separate windings have the same magnitude but a
different frequency, under load and no load
operation. The reversing regime is also simulated
under unbalanced supply conditions. The results
offer the perspective to design electromechanical
systems with speed or rotation angle expressed as
harmonic, quasi-harmonic or even random variation
laws.
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37-47 |
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The Methods of Multi
Attribute Analysis in Application to Assess Optimal
Factor Combination in One Experiment
D. Randjelovic, C. Dolicanin
Abstract: Experiments are used by
scientists to affirm their hypothesis, these
experiments are called tests in research, or to
choose the best from available possibilities, these
experiments are called valuations in research in
which group belongs also optimal factor combination
choice in one multifactor and often multivariate
experiments. For decreasing influence ever present
uncontrolled factors i.e. experimental error
researchers make different plans. Mathematical
instruments of most effective plans for experiment
organization are possible to search on the basis of
total random distribution, random block distribution
and some special organized block distribution while
they can most effectively represent complex
multifactor and multivariate experiments. Statistic
analysis for any experiment plan is very complex in
the standard way with analysis of variance and
multiple linear regression and especially in the
case of the optimal factor combination choice. From
other side multiple criteria analysis like modern
science discipline enables an easier way to make
analysis of results of one experiment just in the
case of optimal factor combination choice of one
multifactor and multivariate experiment. Therefore
authors propose multiple criteria analysis
application in analysis of experiment results and in
this paper authors consider application of one
subgroup of these methods, so called multi attribute
decision methods, to which belong and ELECTRA
method. One example of multiple attribute analysis
application in analysis of results of one experiment
is given in the end of this paper.
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48-57 |
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Efficient Mixing in
Microchannel by using Magnetic Nanoparticles
T. N. Le, Y. K. Suh, S. Kang
Abstract: Rapid and efficient mixing
in microchannel using magnetic nanoparticles has
been numerically investigated. The magnetic
nanoparticles are introduced into the microchannel
and are exerted by the external magnetic force to
cause the vortex motion of the fluid for mixing. The
velocity field of the flow and trajectories of the
particles are solved implicitly by using the Finite
Volume Method (FVM). The obtained results illustrate
the significant effects of the magnetic actuation
force, the switching frequency, number of magnetic
nanoparticles on the mixing efficiency. The mixing
properties of the flow predicted by numerical
simulation are studied under the concentration
field, mixing index and Poincare section.
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58-67 |
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Excitation Control of Self
Excited Induction Generator using Genetic Algorithm
and Artificial Neural Network
Dheeraj Joshi, K. S. Sandhu
Abstract: Induction generators which
may be operated in grid or self-excited mode, are
found to be successful machines for wind energy
conversion. Out of these two self-excited mode is
gaining importance due to its ability to convert the
wind energy into electrical energy for large
variations in operating speed. However it has been
found that these machine exhibits a poor voltage
regulation. Steady-state analysis of self excited
induction generator reveals that such generators are
not capable to maintain the terminal voltage and
frequency in the absence of expensive controllers.
In turn addition of such controllers may result into
a fall in popularity of this machine due to its
simplicity. Another simple way to control the
terminal voltage is through excitation control using
series compensation. In this paper artificial
intelligent techniques are used to model the control
strategy for proper reactive compensation under
different operating conditions. Genetic algorithm
along with artificial neural network has been
proposed to estimate the values of shunt and series
excitation capacitance to maintain the terminal and
load voltage. Simulated results as found using
proposed control technique are verified using
experimental results on a test machine. Simulated
results are found to be in close agreement with
experimental results.
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68-75 |
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Paper
Title, Authors, Abstract (Issue 2, Volume 3, 2009) |
Pages |
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Estimate to the Trajectory
of Maneuvering Targets by Combining Sensor
Scheduling with Energy Efficient in WSNs
Joy Iong-Zong Chen, Chih-Chung Yu
Abstract: An algorithm by combining
sensor scheduling with energy efficient for tracking
the maneuvering targets with mobile sensor deployed
in WSNs (wireless sensor networks) is proposed to
investigate the tracking performance in the article.
In order to minimize the estimated error, the sensor
sequence and the optimal sensor movement are
scheduled previously and determined first. Thus, the
sensor scheduling is depending on the results from
the evaluation of energy efficient of a sensor node.
Moreover, due to the targets is varying with time in
the estimation process the EKF (extended Kalman
filtering) technique is applied to predict MSE (mean
square error) of a predicted target. Finally,
simulations by using of the scenario with two and
four maneuvering targets tracking are held to
validate the accuracy of the proposed algorithm, and
the results definitely show the fact that the MSE
will decrease when the right way of the sensor
scheduling is arranged previously.
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77-84 |
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Time Series Modeling using
an Adaptive Gene Expression Programming Algorithm
Alina Barbulescu, Elena Bautu
Abstract: Meteorological time series
are characterized by important spatial and temporal
variation. Model determination and the prediction of
evolution of such series is of high importance for
different practical purposes, even if discovering
evolution patterns in such series is a very
difficult problem. In this article we describe an
adaptive evolutionary technique and we apply it for
modeling the precipitation and temperatures
collected in a region of Romania. The results are
promising for the analysis of such time series.
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85-93 |
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A Multi-Item Production Lot
Size Inventory Model with Cycle Dependent Parameters
Zaid T. Balkhi, Abdelaziz Foul
Abstract: In this paper, a multi-item
production inventory model is considered within a
given time horizon that consists of different time
periods. For each product, production, demand, and
deterioration rates in each period are known.
Shortage for each product is allowed but it is
completely backlogged . The objective is to find the
optimal production and restarting times for each
product in each period so that the overall total
inventory cost for all products is minimized. In
this paper, a formulation of the problem is
developed and optimization techniques are performed
to show uniqueness and global optimality of the
solution.
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94-104 |
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Stochastic Geolithological
Reconstruction coupled with Artificial Neural
Networks Approach for Hydrogeological Modeling
Claudia Cherubini, Fausta Musci, Nicola Pastore
Abstract: When simulating fluid flow
and solute transport a more accurate modeling of the
lithologic, geological and structural characters of
an aquifer is of extreme importance in order to
improve the reliability of the numerical
simulations. On the other hand the information
available for the setting up of a hydrogeological
model is subjected to ambiguities due to not
univocal interpretations or to uncertainties linked
to the methodologies of measurement of the variables
of interest. Therefore, hydrogeological
characterization of heterogeneous aquifers, if
carried out up to a high degree of detail, should
not identify a univocal model but a set of
“equifinal” solutions. In the present paper the
application of Artificial Neural Network approach
coupled with a Nested Sequential Indicator
simulation has allowed to obtain the distribution of
hydrogeologic parameters that are not only
conditioned by the in situ measured values but also
by the soft information coming from geolithology.
The results show a fairly good relationship between
parameters such as Transmissivity and Storage
coefficient and the geolithologic architecture of
the examined aquifer.
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105-114 |
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Formal Transformation from
NFA to Z Notation by Constructing Union of Regular
Languages
Nazir Ahmad Zafar, Nabeel Sabir, Amir Ali
Abstract: Capturing functionalities
and modeling control behavior are primary
requirements in design and development of a complex
system. Automata theory plays a vital role in
modeling behavior while Z notation is an ideal
specification language for describing state space of
a system. Consequently, integration of automata and
Z notation will be a useful tool facilitating and
increasing modeling power for complex systems.
Further, nondeterministic finite automata (NFA) may
have different implementations and therefore it is
needed to verify the transformation from diagrams to
code. If we describe formal specification of a given
nondeterministic finite automata before implementing
then confidence over transformation can be
increased. In this paper, we have combined NFA and Z
and a linkage is established between these
approaches. At this level of integration, we have
given a formal procedure to transform NFA to Z. A
string accepter is designed and then extended to the
language accepter. Finally, NFA accepting union of
two regular languages is constructed by describing
formal specification of their relationships. The
specification is analyzed and validated using Z/EVES
tool.
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115-122 |
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Identification of the
De-synchronization, Synchronization and Forced
Oscillation Phenomenon of a Nonlinear System
Marius-Constantin O.S. Popescu, Onisifor V. Olaru,
Valentina E. Balas
Abstract: The phenomena of
de-synchronization, synchronization, and forced
oscillation has been investigation using describing
function theory for a two input and two output
nonlinear system containing saturation-type
nonlinearities and subjected to high-frequency
deterministic signal for the purpose of limit cycle
quenching. The analytical results have been compared
with the results of digital simulation Matlab-Simulink
for a typical example varying the nonlinear element.
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123-132 |
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Equilibrium Dynamic Systems
Intelligence
Marius-Constantin O.S. Popescu, Onisifor V. Olaru,
Nikos E. Mastorakis
Abstract: Most work in Artificial
Intelligence reviews the balance of classic game
theory to predict agent behavior in different
positions. In this paper we introduce steady
competitive analysis. This approach bridges the gap
between the standards of desired paths of artificial
intelligence, where a strategy must be selected in
order to ensure an end result and a balanced
analysis. We show that a strategy without risk level
is able to guarantee the value obtained in the Nash
equilibrium, by more scientific methods of classical
computers. Then we will discuss the concept of
competitive strategy and illustrate how it is used
in a decentralized load balanced position, typical
for network problems. In particular, we will show
that when there are many agents, it is possible to
guarantee an expected final result, which is a 8/9
factor of the final result obtained in the Nash
equilibrium. Finally, we will discuss about
extending the above concept in Bayesian game and
illustrate its use in a basic structure of an
auction.
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133-142 |
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Suggestions of
Nanotechnology Park and Observations on Industrial
Challenges
Ahmet Karakas
Abstract: This study aims to clarify
the establishment of the Nanotechnology Park in
South Wales .The feasibility is observed through a
survey, and reliability of the survey participants
is justified with question structures. As the idea
is a unique concept, the survey outcome is analyzed
together with recent research and it is aimed to
fill the gap in the field. Due to the nature of
nanotechnology organizations, the challenges of the
industry as well as the researchers are observed.
Financial and organizational difficulties of the
start-up companies are observed, including the
constraints of the industry and research
institutions. The outline and proposed issues to be
considered are addressed for a nanotechnology park.
Multi-disciplined field structure is observed and
criticized with the current applications. Further
research recommendations are pointed out through
finalizing this study.
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143-151 |
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Checking Simulations of a
Geolithological Model Obtained by Means of Nested
Truncated Bigaussian Method
Claudia Cherubini, Fausta Musci, Nicola Pastore
Abstract: Characterizing the spatial
distribution of major lithotypes and their
relationships is a key aspect in the process of
hydrogeological modeling of aquifers in that
assignment of lithotypes-specific hydraulic and
hydrochemical properties requires the knowledge of
the layout of the lithotypes themselves. Truncated
bigaussian simulation is a procedure derived from
the truncated Gaussian model, used to simulate
random sets, and, in particular, variable geological
characteristics, expressed as categorical variables.
Anyway, in cases of many lithotypes having not
homogeneous spatial behaviors, this methodology
might not explain at best the relations existing
among the lithotypes themselves; a more general
method is therefore required to represent this
variability. In this paper, that concerns a site
whose geologic asset has already been reconstructed,
in order to better characterize the aquifer
geolithological architecture, nested simulation for
a macro-unit of the previously realized
geolithologic model has been carried out, together
with a check phase of the results obtained by the
mentioned simulation. The proposed methodology can
represent a useful instrument for the modeling of
complex geological layouts other than in the
detailed characterizations of hydrogeological
studies, for a better interpretation of the complex
phenomena that take place in groundwater circulation
and contaminant propagation.
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152-161 |
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A Simulation Study of
Additive Outlier in ARMA (1, 1) Model
Azami Zaharim, Rafizah Rajali, Raden Mohamad Atok,
Ibrahim Mohamed, Khamisah Jafar
Abstract: Abnormal observation due to
an isolated incident such as a recording error is
known as additive outlier and it is often found in
time series. Since extreme value of additive
outliers may contribute to the inaccuracy of model
specification, proper detection procedure is
significant to avoid such error. Equations that
explain the nature of an additive outlier and the
test statistics pertaining to it are discussed in
this article. This is followed by two separate
simulation studies that are conducted to investigate
the sampling behavior and detection performance of
the test statistics in ARMA (1, 1) models. Results
for the first simulation study show that the test
statistics is an increasing function of sample size.
Whilst in the other simulation study we see that the
performance of the test statistics improves as large
magnitudes of outlier effect are used.
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162-169 |
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