Abstract: A method is presented for the construction of arbitrary
even-input sorting networks exhibiting better properties than the
networks created using a conventional technique of the same type.
The method was discovered by means of a genetic algorithm combined
with an application-specific development. Similarly to human
inventions in the area of theoretical computer science, the evolved
invention was analyzed: its generality was proven and area and time
complexities were determined.
Abstract: A study of electromagnetic flow meter is presented in the paper. Comparison has been made between the analytical and the numerical results by the use of FEM numerical analysis (Quick Field 5.6) for determining polarization voltage through the circle cross section of the polarization transducer. Exciting and geometrical parameters increasing its effectiveness has been examined. The aim is to obtain maximal output signal. The investigations include different variants of the magnetic flux density distribution around the tube: homogeneous field of magnitude Bm, linear distribution with maximal value Bm and trapezium distribution conserving the same exciting magnetic energy as the homogeneous field.
Abstract: Unsteady magnetohydrodynamics (MHD) boundary
layer flow and heat transfer over a continuously stretching surface in
the presence of radiation is examined. By similarity transformation,
the governing partial differential equations are transformed to a set of
ordinary differential equations. Numerical solutions are obtained by
employing the Runge-Kutta-Fehlberg method scheme with shooting
technique in Maple software environment. The effects of
unsteadiness parameter, radiation parameter, magnetic parameter and
Prandtl number on the heat transfer characteristics are obtained and
discussed. It is found that the heat transfer rate at the surface
increases as the Prandtl number and unsteadiness parameter increase
but decreases with magnetic and radiation parameter.
Abstract: There is a growing body of evidence to support the
proposition of product take back for remanufacturing particularly
within the context of Extended Producer Responsibility (EPR).
Remanufacturing however presents challenges unlike that of
traditional manufacturing environments due to its high levels of
uncertainty which may further distract organizations from
considering its potential benefits. This paper presents a novel
modeling approach for evaluating the uncertainty of part failures
within the remanufacturing process and its impact on economic and
environmental performance measures. This paper presents both the
theoretical modeling approach and an example of its use in
application.
Abstract: This paper presents the utilizing of ferroelectric
material on antenna application. There are two different ferroelectric
had been used on the proposed antennas which include of Barium
Strontium Titanate (BST) and Bismuth Titanate (BiT), suitable for
Access Points operating in the WLAN IEEE 802.11 b/g and WiMAX
IEEE 802.16 within the range of 2.3 GHz to 2.5 GHz application.
BST, which had been tested to own a dielectric constant of εr = 15
while BiT has a dielectric constant that higher than BST which is εr =
21 and both materials are in rectangular shaped. The influence of
various parameters on antenna characteristics were investigated
extensively using commercial electromagnetic simulations software
by Communication Simulation Technology (CST). From theoretical
analysis and simulation results, it was demonstrated that ferroelectric
material used have not only improved the directive emission but also
enhanced the radiation efficiency.
Abstract: Extracellular ubiquitin in vivo effect on regenerative liver cells and liver histoarchitectonics has been studied. Experiments were performed on mature female white rats. Partial hepatectomy was made using the modified method of Higgins and Anderson. Standard histopathological assessment of liver tissue was used. Proliferative activity of hepatocytes was analyzed by colchicine mitotic index and immunohistochemical staining on ki67. We have found that regardless of number of injections and dose of extracellular ubiquitin liver histology has not been changed, so at tissue level no effect was observed. In vivo double injection of ubiquitin significantly decreases the mitotic activity at 32 hour point after partial hepatectomy. Thus, we can conclude that in vivo injected extracellular ubiquitin inhibits proliferative activity of hepatocytes in partially hepatectomyzed rats.
Abstract: This study deals with the phenomena of reflection and transmission (refraction) of qSV-waves, for an incident of quasi transverse vertically waves, at a plane interface of two semi-infinite piezoelectric elastic media under the influence of the initial stresses. The relations governing the reflection and transmission coefficients of these reflected waves for various suitable boundary conditions are derived. We have shown analytically that reflection and transmission coefficients of (qP) and (qSV) waves depend upon the angle of incidence, the parameters of electric potential, the material constants of the medium as will as the initial stresses presented in the media. The numerical calculations of the reflection and transmission amplitude ratios for different values of initial stresses have been carried out by computer for different materials as examples and the results are given in the form of graphs. Finally, some of particular cases are considered.
Abstract: This paper describes a novel and effective approach to content-based image retrieval (CBIR) that represents each image in the database by a vector of feature values called “Standard deviation of mean vectors of color distribution of rows and columns of images for CBIR". In many areas of commerce, government, academia, and hospitals, large collections of digital images are being created. This paper describes the approach that uses contents as feature vector for retrieval of similar images. There are several classes of features that are used to specify queries: colour, texture, shape, spatial layout. Colour features are often easily obtained directly from the pixel intensities. In this paper feature extraction is done for the texture descriptor that is 'variance' and 'Variance of Variances'. First standard deviation of each row and column mean is calculated for R, G, and B planes. These six values are obtained for one image which acts as a feature vector. Secondly we calculate variance of the row and column of R, G and B planes of an image. Then six standard deviations of these variance sequences are calculated to form a feature vector of dimension six. We applied our approach to a database of 300 BMP images. We have determined the capability of automatic indexing by analyzing image content: color and texture as features and by applying a similarity measure Euclidean distance.
Abstract: There are two paradigms proposed to provide QoS for Internet applications: Integrated service (IntServ) and Differentiated service (DiffServ).Intserv is not appropriate for large network like Internet. Because is very complex. Therefore, to reduce the complexity of QoS management, DiffServ was introduced to provide QoS within a domain using aggregation of flow and per- class service. In theses networks QoS between classes is constant and it allows low priority traffic to be effected from high priority traffic, which is not suitable. In this paper, we proposed a fuzzy controller, which reduced the effect of low priority class on higher priority ones. Our simulations shows that, our approach reduces the latency dependency of low priority class on higher priority ones, in an effective manner.
Abstract: For maintenance of a spine stability during the
postoperative period a transpedicular fixing of its elements is often
used. Usually the transpedicular systems are formed of rods which as
a result form a design of the frame type, fastening by screws to
vertebras. Such design should be rigid and perceive loadings
operating from the spine without essential deformations. From the
perfection point of view of known designs their stress
whole, and each of elements, in particular is of interest. In this study
the modeling of the transpedicular screw is performed and
estimation of its deformations taking into account interaction with a
vertebra body having variable structure is made.
Abstract: The client server systems using mobile
communications networks for data transmission became very
attractive for many economic agents, in the purpose of promoting and
offering electronic services to their clients. E-services are suitable for
business developing and financial benefits increasing. The products
or services can be efficiently delivered to a large number of clients,
using mobile Internet access technologies. The clients can have
access to e-services, anywhere and anytime, with the support of 3G,
GPRS, WLAN, etc., channels bandwidth, data services and protocols.
Based on the mobile communications networks evolution and
development, a convergence of technological and financial interests
of mobile operators, software developers, mobile terminals producers
and e-content providers is established. These will lead to a high level
of integration of IT&C resources and will facilitate the value added
services delivery through the mobile communications networks. In
this paper it is presented a client server system, for e-services access,
with Smartphones and PDA-s mobile software applications, installed
on Symbian and Windows Mobile operating systems.
Abstract: According to the density of the chips, designers are
trying to put so any facilities of computational and storage on single
chips. Along with the complexity of computational and storage
circuits, the designing, testing and debugging become more and more
complex and expensive. So, hardware design will be built by using
very high speed hardware description language, which is more
efficient and cost effective. This paper will focus on the
implementation of 32-bit ALU design based on Verilog hardware
description language. Adder and subtracter operate correctly on both
unsigned and positive numbers. In ALU, addition takes most of the
time if it uses the ripple-carry adder. The general strategy for
designing fast adders is to reduce the time required to form carry
signals. Adders that use this principle are called carry look- ahead
adder. The carry look-ahead adder is to be designed with combination
of 4-bit adders. The syntax of Verilog HDL is similar to the C
programming language. This paper proposes a unified approach to
ALU design in which both simulation and formal verification can
co-exist.
Abstract: In designing river intakes and diversion structures, it is paramount that the sediments entering the intake are minimized or, if possible, completely separated. Due to high water velocity, sediments can significantly damage hydraulic structures especially when mechanical equipment like pumps and turbines are used. This subsequently results in wasting water, electricity and further costs. Therefore, it is prudent to investigate and analyze the performance of lateral intakes affected by sediment control structures. Laboratory experiments, despite their vast potential and benefits, can face certain limitations and challenges. Some of these include: limitations in equipment and facilities, space constraints, equipment errors including lack of adequate precision or mal-operation, and finally, human error. Research has shown that in order to achieve the ultimate goal of intake structure design – which is to design longlasting and proficient structures – the best combination of sediment control structures (such as sill and submerged vanes) along with parameters that increase their performance (such as diversion angle and location) should be determined. Cost, difficulty of execution and environmental impacts should also be included in evaluating the optimal design. This solution can then be applied to similar problems in the future. Subsequently, the model used to arrive at the optimal design requires high level of accuracy and precision in order to avoid improper design and execution of projects. Process of creating and executing the design should be as comprehensive and applicable as possible. Therefore, it is important that influential parameters and vital criteria is fully understood and applied at all stages of choosing the optimal design. In this article, influential parameters on optimal performance of the intake, advantages and disadvantages, and efficiency of a given design are studied. Then, a multi-criterion decision matrix is utilized to choose the optimal model that can be used to determine the proper parameters in constructing the intake.
Abstract: Noise contamination in a magnetic resonance (MR)
image could occur during acquisition, storage, and transmission in
which effective filtering is required to avoid repeating the MR
procedure. In this paper, an iterative asymmetrical triangle fuzzy
filter with moving average center (ATMAVi filter) is used to reduce
different levels of salt and pepper noise in a brain MR image. Besides
visual inspection on filtered images, the mean squared error (MSE) is
used as an objective measurement. When compared with the median
filter, simulation results indicate that the ATMAVi filter is effective
especially for filtering a higher level noise (such as noise density =
0.45) using a smaller window size (such as 3x3) when operated
iteratively or using a larger window size (such as 5x5) when operated
non-iteratively.
Abstract: In this study, an analysis has been performed for
heat and mass transfer of a steady laminar boundary-layer flow
of a viscous flow past a nonlinearly stretching sheet.
Parameters n, Ec, k0, Sc represent the dominance of the
nonlinearly effect, viscous effect, radiation effect and mass
transfer effect which have presented in governing equations,
respectively. The similarity transformation and the
finite-difference method have been used to analyze the present
problem.
Abstract: Today-s economy is in a permanent change, causing
merger and acquisitions and co operations between enterprises. As a
consequence, process adaptations and realignments result in systems
integration and software development projects. Processes and
procedures to execute such projects are still reliant on craftsman-ship
of highly skilled workers. A generally accepted, industrialized
production, characterized by high efficiency and quality, seems
inevitable.
In spite of this, current concepts of software industrialization are
aimed at traditional software engineering and do not consider the
characteristics of systems integration. The present work points out
these particularities and discusses the applicability of existing
industrial concepts in the systems integration domain. Consequently
it defines further areas of research necessary to bring the field of
systems integration closer to an industrialized production, allowing a
higher efficiency, quality and return on investment.
Abstract: Global competitiveness has recently become the
biggest concern of both manufacturing and service companies.
Electronic commerce, as a key technology enables the firms to reach
all the potential consumers from all over the world. In this study, we
have presented commonly used electronic payment systems, and then
we have shown the evaluation of these systems in respect to different
criteria. The payment systems which are included in this research are
the credit card, the virtual credit card, the electronic money, the
mobile payment, the credit transfer and the debit instruments. We
have realized a systematic comparison of these systems in respect to
three main criteria: Technical, economical and social. We have
conducted a fuzzy multi-criteria decision making procedure to deal
with the multi-attribute nature of the problem. The subjectiveness
and imprecision of the evaluation process are modeled using
triangular fuzzy numbers.
Abstract: In the present paper; an experimental and numerical
investigations of drag reduction on a grooved circular cylinder have
been performed. The experiments were carried out in closed circuit
subsonic wind tunnel (TE44); the pressure distribution on the
cylinder was conducted using a TE44DPS differential pressure
scanner and the drag forces were measured using the TE81 balance.
The display unit is linked to a computer, loaded with DATASLIM
software for data analysis and logging of result. The numerical study
was performed using the code ANSYS FLUENT solving the
Reynolds Averaged Navier-Stokes (RANS) equations. The k-ε and k-
ω SST models were tested. The results obtained from the
experimental and numerical investigations have showed a reduction
in the drag when using longitudinal grooves namely 2 and 6 on the
cylinder.
Abstract: The transient analysis of a queuing system with fixed-size batch Poisson arrivals and a single server with exponential service times is presented. The focus of the paper is on the use of the functions that arise in the analysis of the transient behaviour of the queuing system. These functions are shown to be a generalization of the modified Bessel functions of the first kind, with the batch size B as the generalizing parameter. Results for the case of single-packet arrivals are obtained first. The similarities between the two families of functions are then used to obtain results for the general case of batch arrival queue with a batch size larger than one.
Abstract: Block replacement algorithms to increase hit ratio
have been extensively used in cache memory management. Among
basic replacement schemes, LRU and FIFO have been shown to be
effective replacement algorithms in terms of hit rates. In this paper,
we introduce a flexible stack-based circuit which can be employed in
hardware implementation of both LRU and FIFO policies. We
propose a simple and efficient architecture such that stack-based
replacement algorithms can be implemented without the drawbacks
of the traditional architectures. The stack is modular and hence, a set
of stack rows can be cascaded depending on the number of blocks in
each cache set. Our circuit can be implemented in conjunction with
the cache controller and static/dynamic memories to form a cache
system. Experimental results exhibit that our proposed circuit
provides an average value of 26% improvement in storage bits and its
maximum operating frequency is increased by a factor of two