Abstract: The competitive learning is an adaptive process in
which the neurons in a neural network gradually become sensitive to
different input pattern clusters. The basic idea behind the Kohonen-s
Self-Organizing Feature Maps (SOFM) is competitive learning.
SOFM can generate mappings from high-dimensional signal spaces
to lower dimensional topological structures. The main features of this
kind of mappings are topology preserving, feature mappings and
probability distribution approximation of input patterns. To overcome
some limitations of SOFM, e.g., a fixed number of neural units and a
topology of fixed dimensionality, Growing Self-Organizing Neural
Network (GSONN) can be used. GSONN can change its topological
structure during learning. It grows by learning and shrinks by
forgetting. To speed up the training and convergence, a new variant
of GSONN, twin growing cell structures (TGCS) is presented here.
This paper first gives an introduction to competitive learning, SOFM
and its variants. Then, we discuss some GSONN with fixed
dimensionality, which include growing cell structures, its variants
and the author-s model: TGCS. It is ended with some testing results
comparison and conclusions.
Abstract: In this paper we improve the quasilinearization method by barycentric Lagrange interpolation because of its numerical stability and computation speed to achieve a stable semi analytical solution. Then we applied the improved method for solving the Fin problem which is a nonlinear equation that occurs in the heat transferring. In the quasilinearization approach the nonlinear differential equation is treated by approximating the nonlinear terms by a sequence of linear expressions. The modified QLM is iterative but not perturbative and gives stable semi analytical solutions to nonlinear problems without depending on the existence of a smallness parameter. Comparison with some numerical solutions shows that the present solution is applicable.
Abstract: The paper is intended to declare and apply ethics, i. e.
moral principles, rules in marketing environment. Ethical behavior of
selected pharmaceutical companies in the Slovak Republic is the
object of our research. The aim of our research is to determine
perception of ethical behavior of the pharmaceutical industry in
Slovakia by the medicine representatives in comparison with the
assessment of doctors and patients. The experimental sample
included 90 participants who were divided into three groups:
medicine representatives of the pharmaceutical companies (N=30),
doctors (N=30) and patients (N=30). The research method was a
Questionnaire of ethical behavior, created by us, that describes
individual areas included in the Code of ethics of the pharmaceutical
industry in Slovakia. The results showed influence of professional
status on ethical behavior perception, not gender. Higher perception
was indicated at patients rather than doctors and medicine
representatives.
Abstract: The present work presents a method of calculating the
ductility of rectangular sections of beams considering nonlinear
behavior of concrete and steel. This calculation procedure allows us
to trace the curvature of the section according to the bending
moment, and consequently deduce ductility. It also allowed us to
study the various parameters that affect the value of the ductility. A
comparison of the effect of maximum rates of tension steel, adopted
by the codes, ACI [1], EC8 [2] and RPA [3] on the value of the
ductility was made. It was concluded that the maximum rate of steels
permitted by the ACI [1] codes and RPA [3] are almost similar in
their effect on the ductility and too high. Therefore, the ductility
mobilized in case of an earthquake is low, the inverse of code EC8
[2]. Recommendations have been made in this direction.
Abstract: Soils are normally dried in either a convection oven or stove. Laboratory moisture content testing indicated that the typical drying durations for a convection oven were, 24 hours. The purpose of this study was to determine the accuracy and soil drying duration of both, moisture content and liquid limit using microwave radiation. The soils were tested with both, convection and microwave ovens. The convection oven was considered to produce the true values for both, natural moisture content and liquid limit of soils; it was, therefore, used as a basis for comparison for the results of the microwave ovens. The samples used in this study were obtained from different projects of Consulting Engineering Bureau of College of Engineering of Sulaimani University. These samples were collected from different locations and at the different depths and consist mostly of brown and light brown clay and silty clay. A total of 102 samples were prepared. 26 of them were tested for natural moisture determination, while the other 76 were used for liquid limits determination
Abstract: Information technology managers nowadays are
facing with tremendous pressure to plan, implement, and adopt new
technology solution due to the rapidity of technology changes.
Resulted from a lack of study that have been done in this topic, the
aim of this paper is to provide a comparison review on current tools
that are currently being used in order to respond to technological
changes. The study is based on extensive literature review of
published works with majority of them are ranging from 2000 to the
first part of 2011. The works were gathered from journals, books,
and other information sources available on the Web. Findings show
that, each tools has different focus and none of the tools are
providing a framework in holistic view, which should include
technical, people, process, and business environment aspect. Hence,
this result provides potential information about current available
tools that IT managers could use to manage changes in technology.
Further, the result reveals a research gap in the area where the
industries a short of such framework.
Abstract: Image synthesis is an important area in image processing.
To synthesize images various systems are proposed in
the literature. In this paper, we propose a bio-inspired system to
synthesize image and to study the generating power of the system, we
define the class of languages generated by our system. We call image
as array in this paper. We use a primitive called iso-array to synthesize
image/array. The operation is double splicing on iso-arrays. The
double splicing operation is used in DNA computing and we use
this to synthesize image. A comparison of the family of languages
generated by the proposed self restricted double splicing systems on
iso-arrays with the existing family of local iso-picture languages is
made. Certain closure properties such as union, concatenation and
rotation are studied for the family of languages generated by the
proposed model.
Abstract: The value of overall oxygen transfer Coefficient
(KLa), which is the best measure of oxygen transfer in water through
aeration, is obtained by a simple approach, which sufficiently
explains the utility of the method to eliminate the discrepancies due
to inaccurate assumption of saturation dissolved oxygen
concentration. The rate of oxygen transfer depends on number of
factors like intensity of turbulence, which in turns depends on the
speed of rotation, size, and number of blades, diameter and
immersion depth of the rotor, and size and shape of aeration tank, as
well as on physical, chemical, and biological characteristic of water.
An attempt is made in this paper to correlate the overall oxygen
transfer Coefficient (KLa), as an independent parameter with other
influencing parameters mentioned above. It has been estimated that
the simulation equation developed predicts the values of KLa and
power with an average standard error of estimation of 0.0164 and
7.66 respectively and with R2 values of 0.979 and 0.989 respectively,
when compared with experimentally determined values. The
comparison of this model is done with the model generated using
Computational fluid dynamics (CFD) and both the models were
found to be in good agreement with each other.
Abstract: A new conserving approach in the context of Immersed Boundary Method (IBM) is presented to simulate one dimensional, incompressible flow in a moving boundary problem. The method employs control volume scheme to simulate the flow field. The concept of ghost node is used at the boundaries to conserve the mass and momentum equations. The Present method implements the conservation laws in all cells including boundary control volumes. Application of the method is studied in a test case with moving boundary. Comparison between the results of this new method and a sharp interface (Image Point Method) IBM algorithm shows a well distinguished improvement in both pressure and velocity fields of the present method. Fluctuations in pressure field are fully resolved in this proposed method. This approach expands the IBM capability to simulate flow field for variety of problems by implementing conservation laws in a fully Cartesian grid compared to other conserving methods.
Abstract: Human activity is a major concern in a wide variety of
applications, such as video surveillance, human computer interface
and face image database management. Detecting and recognizing
faces is a crucial step in these applications. Furthermore, major
advancements and initiatives in security applications in the past years
have propelled face recognition technology into the spotlight. The
performance of existing face recognition systems declines significantly
if the resolution of the face image falls below a certain level.
This is especially critical in surveillance imagery where often, due to
many reasons, only low-resolution video of faces is available. If these
low-resolution images are passed to a face recognition system, the
performance is usually unacceptable. Hence, resolution plays a key
role in face recognition systems. In this paper we introduce a new
low resolution face recognition system based on mixture of expert
neural networks. In order to produce the low resolution input images
we down-sampled the 48 × 48 ORL images to 12 × 12 ones using
the nearest neighbor interpolation method and after that applying
the bicubic interpolation method yields enhanced images which is
given to the Principal Component Analysis feature extractor system.
Comparison with some of the most related methods indicates that
the proposed novel model yields excellent recognition rate in low
resolution face recognition that is the recognition rate of 100% for
the training set and 96.5% for the test set.
Abstract: In this article a modification of the algorithm of the fuzzy ART network, aiming at returning it supervised is carried out. It consists of the search for the comparison, training and vigilance parameters giving the minimum quadratic distances between the output of the training base and those obtained by the network. The same process is applied for the determination of the parameters of the fuzzy ARTMAP giving the most powerful network. The modification consist in making learn the fuzzy ARTMAP a base of examples not only once as it is of use, but as many time as its architecture is in evolution or than the objective error is not reached . In this way, we don-t worry about the values to impose on the eight (08) parameters of the network. To evaluate each one of these three networks modified, a comparison of their performances is carried out. As application we carried out a classification of the image of Algiers-s bay taken by SPOT XS. We use as criterion of evaluation the training duration, the mean square error (MSE) in step control and the rate of good classification per class. The results of this study presented as curves, tables and images show that modified fuzzy ARTMAP presents the best compromise quality/computing time.
Abstract: This research paper presents some methods to assess the performance of Wigner Ville Distribution for Time-Frequency representation of non-stationary signals, in comparison with the other representations like STFT, Spectrogram etc. The simultaneous timefrequency resolution of WVD is one of the important properties which makes it preferable for analysis and detection of linear FM and transient signals. There are two algorithms proposed here to assess the resolution and to compare the performance of signal detection. First method is based on the measurement of area under timefrequency plot; in case of a linear FM signal analysis. A second method is based on the instantaneous power calculation and is used in case of transient, non-stationary signals. The implementation is explained briefly for both methods with suitable diagrams. The accuracy of the measurements is validated to show the better performance of WVD representation in comparison with STFT and Spectrograms.
Abstract: Prediction of viscosity of natural gas is an important parameter in the energy industries such as natural gas storage and transportation. In this study viscosity of different compositions of natural gas is modeled by using an artificial neural network (ANN) based on back-propagation method. A reliable database including more than 3841 experimental data of viscosity for testing and training of ANN is used. The designed neural network can predict the natural gas viscosity using pseudo-reduced pressure and pseudo-reduced temperature with AARD% of 0.221. The accuracy of designed ANN has been compared to other published empirical models. The comparison indicates that the proposed method can provide accurate results.
Abstract: Explosions may cause intensive damage to buildings
and sometimes lead to total and progressive destruction. Pressures
induced by explosions are one of the most destructive loads a
structure may experience. While designing structures for great
explosions may be expensive and impractical, engineers are looking
for methods for preventing destructions resulted from explosions. A
favorable structural system is a system which does not disrupt totally
due to local explosion, since such structures sustain less loss in
comparison with structural ones which really bear the load and
suddenly disrupt. Designing and establishing vital and necessary
installations in a way that it is resistant against direct hit of bomb and
rocket is not practical, economical, or expedient in many cases,
because the cost of construction and installation with such
specifications is several times more than the total cost of the related
equipment.
Abstract: This research aims to study the lead pollution in the air of Babylon governorate that resulted generally from vehicles exhausts in addition to industrial and human activities.Vehicles number in Babylon governorate increased significantly after year 2003 that resulted with increase in lead emissions into the air.Measurement of lead emissions was done in seven stations distributed randomly in Babylon governorate. These stations where located in Industrial (Al-Sena'ay) Quarter, 60 street (near to Babylon sewer directorate), 40 Street (near to the first intersection), Al-Hashmia city, Al-Mahaweel city, , Al- Musayab city in addition to another station in Sayd Idris village belong to Abugharaq district (Agricultural station for comparison). The measured concentrations in these stations were compared with the standard limits of Environmental Protection Agency EPA (2 μg /m3). The results of this study showed that the average of lead concentrations ,in Babylon governorate during year 2010, was (3.13 μg/m3) which was greater than standard limits (2 μg/m3). The maximum concentration of lead was (6.41 μg / m3) recorded in the Industrial (Al-Sena'ay) Quarter during April month, while the minimum concentrations was (0.36 μg / m3) recorded in the agricultural station (Abugharaq) during December month.
Abstract: The paper investigates the potential of support vector
machines and Gaussian process based regression approaches to
model the oxygen–transfer capacity from experimental data of
multiple plunging jets oxygenation systems. The results suggest the
utility of both the modeling techniques in the prediction of the
overall volumetric oxygen transfer coefficient (KLa) from operational
parameters of multiple plunging jets oxygenation system. The
correlation coefficient root mean square error and coefficient of
determination values of 0.971, 0.002 and 0.945 respectively were
achieved by support vector machine in comparison to values of
0.960, 0.002 and 0.920 respectively achieved by Gaussian process
regression. Further, the performances of both these regression
approaches in predicting the overall volumetric oxygen transfer
coefficient was compared with the empirical relationship for multiple
plunging jets. A comparison of results suggests that support vector
machines approach works well in comparison to both empirical
relationship and Gaussian process approaches, and could successfully
be employed in modeling oxygen-transfer.
Abstract: A mammography image is composed of low contrast area where the breast tissues and the breast abnormalities such as microcalcification can hardly be differentiated by the medical practitioner. This paper presents the application of active contour models (Snakes) for the segmentation of microcalcification in mammography images. Comparison on the microcalcifiation areas segmented by the Balloon Snake, Gradient Vector Flow (GVF) Snake, and Distance Snake is done against the true value of the microcalcification area. The true area value is the average microcalcification area in the original mammography image traced by the expert radiologists. From fifty images tested, the result obtained shows that the accuracy of the Balloon Snake, GVF Snake, and Distance Snake in segmenting boundaries of microcalcification are 96.01%, 95.74%, and 95.70% accuracy respectively. This implies that the Balloon Snake is a better segmentation method to locate the exact boundary of a microcalcification region.
Abstract: The present paper was concerned primarily with the
analysis, simulation of the air flow and thermal patterns in a lecture
room. The paper is devoted to numerically investigate the influence
of location and number of ventilation and air conditioning supply and
extracts openings on air flow properties in a lecture room. The work
focuses on air flow patterns, thermal behaviour in lecture room where
large number of students. The effectiveness of an air flow system is
commonly assessed by the successful removal of sensible and latent
loads from occupants with additional of attaining air pollutant at a
prescribed level to attain the human thermal comfort conditions and
to improve the indoor air quality; this is the main target during the
present paper. The study is carried out using computational fluid
dynamics (CFD) simulation techniques as embedded in the
commercially available CFD code (FLUENT 6.2). The CFD
modelling techniques solved the continuity, momentum and energy
conservation equations in addition to standard k – ε model equations
for turbulence closure.
Throughout the investigations, numerical validation is carried out by
way of comparisons of numerical and experimental results. Good
agreement is found among both predictions.
Abstract: In comparison to the original SVM, which involves a
quadratic programming task; LS–SVM simplifies the required
computation, but unfortunately the sparseness of standard SVM is
lost. Another problem is that LS-SVM is only optimal if the training
samples are corrupted by Gaussian noise. In Least Squares SVM
(LS–SVM), the nonlinear solution is obtained, by first mapping the
input vector to a high dimensional kernel space in a nonlinear
fashion, where the solution is calculated from a linear equation set. In
this paper a geometric view of the kernel space is introduced, which
enables us to develop a new formulation to achieve a sparse and
robust estimate.
Abstract: Truss optimization problem has been vastly studied
during the past 30 years and many different methods have been
proposed for this problem. Even though most of these methods
assume that the design variables are continuously valued, in reality,
the design variables of optimization problems such as cross-sectional
areas are discretely valued. In this paper, an improved hill climbing
and an improved simulated annealing algorithm have been proposed
to solve the truss optimization problem with discrete values for crosssectional
areas. Obtained results have been compared to other
methods in the literature and the comparison represents that the
proposed methods can be used more efficiently than other proposed
methods