Abstract: The presented article deals with the description of a
numerical model of a corridor at a Central Interim Spent Fuel Storage
Facility (hereinafter CISFSF). The model takes into account the
effect of air flows on the temperature of stored waste. The
computational model was implemented in the ANSYS/CFX
programming environment in the form of a CFD task solution, which
was compared with an approximate analytical calculation. The article
includes a categorization of the individual alternatives for the
ventilation of such underground systems. The aim was to evaluate a
ventilation system for a CISFSF with regard to its stability and
capacity to provide sufficient ventilation for the removal of heat
produced by stored casks with spent nuclear fuel.
Abstract: This study examines the issue of recommendation
sources from the perspectives of gender and consumers- perceived
risk, and validates a model for the antecedents of consumer online
purchases. The method of obtaining quantitative data was that of the
instrument of a survey questionnaire. Data were collected via
questionnaires from 396 undergraduate students aged 18-24, and a
multiple regression analysis was conducted to identify causal
relationships. Empirical findings established the link between
recommendation sources (word-of-mouth, advertising, and
recommendation systems) and the likelihood of making online
purchases and demonstrated the role of gender and perceived risk as
moderators in this context. The results showed that the effects of
word-of-mouth on online purchase intentions were stronger than those
of advertising and recommendation systems. In addition, female
consumers have less experience with online purchases, so they may be
more likely than males to refer to recommendations during the
decision-making process. The findings of the study will help
marketers to address the recommendation factor which influences
consumers- intention to purchase and to improve firm performances to
meet consumer needs.
Abstract: The study of interaction among the grain, moisture,
and the surrounding space (air) is key to understanding the graindrying
process. In Iran, rice (mostly Indica type) is dried by flat
bed type dryer until the final MC reaches to 6 to 8%. The
experiments were conducted to examine the effect of application of
discharge fan with different heights of paddy on the drying
efficiency. Experiments were designed based on two different
configurations of the drying methods; with and without discharge
fan with three different heights of paddy including; 5, 10, and 15
cm. The humid heated air will be going out immediately by the
suction of discharge fan. The drying time is established upon the
average final MC to achieve about 8%. To save energy and reduce
the drying time, the distribution of temperature between layers
should be fast and uniform with minimum difference; otherwise
the difference of MC gradient between layers will be high and will
induce grain breakage. The difference of final MC between layers
in the two methods was 48-73%. The steady state of temperature
between the two methods has saved time in the range of 10-20%,
and the efficiency of temperature distribution increased 17-26% by
the use of discharge fan.
Abstract: Coverage is one of the main research interests in wireless sensor networks (WSN), it is used to determine the quality of service (QoS) of the networks. Therefore this paper aims to review the common strategies use in solving coverage problem in WSN. The strategies studied are used during deployment phase where the coverage is calculated based on the placement of the sensors on the region of interest (ROI). The strategies reviewed are categorized into three groups based on the approaches used, namely; force based, grid based or computational geometry based approach.
Abstract: The purpose of this paper is to elucidate the flow unsteady behavior for moving plug in convergent-divergent variable thrust nozzle. Compressible axisymmetric Navier-Stokes equations are used to study this physical phenomenon. Different velocities are set for plug to investigate the effect of plug movement on flow unsteadiness. Variation of mass flow rate and thrust are compared under two conditions: First, the plug is placed at different positions and flow is simulated to reach the steady state (quasi steady simulation) and second, the plug is moved with assigned velocity and flow simulation is coupled with plug movement (unsteady simulation). If plug speed is high enough and its movement time scale is at the same order of the flow time scale, variation of the mass flow rate and thrust level versus plug position demonstrate a vital discrepancy under the quasi steady and unsteady conditions. This phenomenon should be considered especially from response time viewpoints in thrusters design.
Abstract: In the past many uneconomic solutions for limitation
and interruption of short-circuit currents in low power applications
have been introduced, especially polymer switch based on the
positive temperature coefficient of resistance (PCTR) concept.
However there are many limitations in the active material, which
consists of conductive fillers. This paper presents a significantly
improved and simplified approach that replaces the existing current
limiters with faster switching elements. Its elegance lies in the
remarkable simplicity and low-cost processes of producing the device
using polyaniline (PANI) doped with methane-sulfonic acid (MSA).
Samples characterized as lying in the metallic and critical regimes of
metal insulator transition have been studied by means of electrical
performance in the voltage range from 1V to 5 V under different
environmental conditions. Moisture presence is shown to increase the
resistivity and also improved its current limiting performance.
Additionally, the device has also been studied for electrical resistivity
in the temperature range 77 K-300 K. The temperature dependence of
the electrical conductivity gives evidence for a transport mechanism
based on variable range hopping in three dimensions.
Abstract: This paper applies fuzzy AHP to evaluate the service
quality of online auction. Service quality is a composition of various
criteria. Among them many intangible attributes are difficult to
measure. This characteristic introduces the obstacles for respondents
on reply in the survey. So as to overcome this problem, we invite
fuzzy set theory into the measurement of performance and use AHP in
obtaining criteria. We found the most concerned dimension of service
quality is Transaction Safety Mechanism and the least is Charge Item.
Other criteria such as information security, accuracy and information
are too vital.
Abstract: The CMLP building was developed to be a model for
sustainability with strategies to reduce water, energy and pollution,
and to provide a healthy environment for the building occupants. The
aim of this paper is to investigate the environmental effects of energy
used by this building. A LCA (life cycle analysis) was led to measure
the real environmental effects produced by the use of energy. The
impact categories most affected by the energy use were found to be
the human health effects, as well as ecotoxicity. Natural gas
extraction, uranium milling for nuclear energy production, and the
blasting for mining and infrastructure construction are the processes
contributing the most to emissions in the human health effect. Data
comparing LCA results of CMLP building with a conventional
building results showed that energy used by the CMLP building has
less damage for the environment and human health than a
conventional building.
Abstract: In this paper we will consider the most known ratios
control schemes ((L/D, V/B),(L/D,V/F), Ryskamp-s, and
(D/(L+D),V/B)) for binary distillation column and we compare them
in the basis of interactions and disturbance propagation. The models
for these configurations are deuced using mathematical
transformations taking the energy balance structure (LV) as a base
model. The dynamic relative magnitude criterion (DRMC) is used to
assess the interactions. The results show that the introduction of
ratios in controlling the column tends to minimize the degree of
interactions between the loops.
Abstract: In the present paper some recommendations for the
use of software package “Mathematica" in a basic numerical analysis
course are presented. The methods which are covered in the course
include solution of systems of linear equations, nonlinear equations
and systems of nonlinear equations, numerical integration,
interpolation and solution of ordinary differential equations. A set of
individual assignments developed for the course covering all the
topics is discussed in detail.
Abstract: In recent years, the use of vector variance as a
measure of multivariate variability has received much attention in
wide range of statistics. This paper deals with a more economic
measure of multivariate variability, defined as vector variance minus
all duplication elements. For high dimensional data, this will increase
the computational efficiency almost 50 % compared to the original
vector variance. Its sampling distribution will be investigated to make
its applications possible.
Abstract: Modular multiplication is the basic operation
in most public key cryptosystems, such as RSA, DSA, ECC,
and DH key exchange. Unfortunately, very large operands
(in order of 1024 or 2048 bits) must be used to provide
sufficient security strength. The use of such big numbers
dramatically slows down the whole cipher system, especially
when running on embedded processors.
So far, customized hardware accelerators - developed on
FPGAs or ASICs - were the best choice for accelerating
modular multiplication in embedded environments. On the
other hand, many algorithms have been developed to speed
up such operations. Examples are the Montgomery modular
multiplication and the interleaved modular multiplication
algorithms. Combining both customized hardware with
an efficient algorithm is expected to provide a much faster
cipher system.
This paper introduces an enhanced architecture for computing
the modular multiplication of two large numbers X
and Y modulo a given modulus M. The proposed design is
compared with three previous architectures depending on
carry save adders and look up tables. Look up tables should
be loaded with a set of pre-computed values. Our proposed
architecture uses the same carry save addition, but replaces
both look up tables and pre-computations with an enhanced
version of sign detection techniques. The proposed architecture
supports higher frequencies than other architectures.
It also has a better overall absolute time for a single operation.
Abstract: This research details a Computational Fluid Dynamics (CFD) approach to model fluid flow in a journal bearing with 8 equispaced semi-circular axial grooves. Water is used as the lubricant and is fed from one end of the bearing to the other, under pressure. The geometry of the bearing is modeled using a commercially available modeling software GAMBIT and the flow analysis is performed using a dedicated CFD analysis software FLUENT. The pressure distribution in the bearing clearance is obtained from FLUENT for various whirl ratios and is used to calculate the hydrodynamic force components in the radial and tangential direction of the bearing. These values along with the various whirl speeds can be used to do a regression analysis to determine the stiffness and damping coefficients. The values obtained are then compared with the stiffness and damping coefficients of a 3 Axial groove water lubricated journal bearing and those obtained from a FORTRAN code for a similar bearing.
Abstract: This paper discusses a curriculum approach that will
give emphasis on practical portions of teaching network security
subjects in information and communication technology courses. As
we are well aware, the need to use a practice and application oriented
approach in education is paramount. Research on active learning and
cooperative groups have shown that students grasps more and have
more tendency towards obtaining and realizing soft skills like
leadership, communication and team work as opposed to the more
traditional theory and exam based teaching and learning. While this
teaching and learning paradigm is relatively new in Malaysia, it has
been practiced widely in the West. This paper examines a certain
approach whereby students learning wireless security are divided into
and work in small and manageable groups where there will be 2
teams which consist of black hat and white hat teams. The former
will try to find and expose vulnerabilities in a wireless network while
the latter will try their best to prevent such attacks on their wireless
networks using hardware, software, design and enforcement of
security policy and etc. This paper will try to show that the approach
taken plus the use of relevant and up to date software and hardware
and with suitable environment setting will hopefully expose students
to a more fruitful outcome in terms of understanding of concepts,
theories and their motivation to learn.
Abstract: In this paper the concept of Q-fuzzification of ideals of Γ-semigroups has been introduced and some important properties have been investigated. A characterization of regular Γ-semigroup in terms of Q-fuzzy ideals has been obtained. Operator semigroups of a Γ-semigroup has been made to work by obtaining various relationships between Q-fuzzy ideals of a Γ-semigroup and that of its operator semigroups.
Abstract: The utility of expert system generators has been
widely recognized in many applications. Several generators based on
concept of the paradigm object, have been recently proposed. The
generator of oriented object expert system (GSEOO) offers
languages that are often complex and difficult to use. We propose in
this paper an extension of the expert system generator, JESS, which
permits a friendly use of this expert system. The new tool, called
VISUAL JESS, bring two main improvements to JESS. The first
improvement concerns the easiness of its utilization while giving
back transparency to the syntax and semantic aspects of the JESS
programming language. The second improvement permits an easy
access and modification of the JESS knowledge basis. The
implementation of VISUAL JESS is made so that it is extensible and
portable.
Abstract: The purpose of this study is mainly to predict collision
frequency on the horizontal tangents combined with vertical curves
using artificial neural network methods. The proposed ANN models
are compared with existing regression models. First, the variables
that affect collision frequency were investigated. It was found that
only the annual average daily traffic, section length, access density,
the rate of vertical curvature, smaller curve radius before and after
the tangent were statistically significant according to related
combinations. Second, three statistical models (negative binomial,
zero inflated Poisson and zero inflated negative binomial) were
developed using the significant variables for three alignment
combinations. Third, ANN models are developed by applying the
same variables for each combination. The results clearly show that
the ANN models have the lowest mean square error value than those
of the statistical models. Similarly, the AIC values of the ANN
models are smaller to those of the regression models for all the
combinations. Consequently, the ANN models have better statistical
performances than statistical models for estimating collision
frequency. The ANN models presented in this paper are
recommended for evaluating the safety impacts 3D alignment
elements on horizontal tangents.
Abstract: Most of the commercial gluten free products are
nutritionally inferior when compared to gluten containing
counterparts as manufacturers most often use the refined flours and
starches. So it is possible that people on gluten free diet have low
intake of fibre content. The foxtail millet flour and copra meal are
gluten free and have high fibre and protein contents. The formulation
of fibre rich gluten free cookies was optimized by response surface
methodology considering independent process variables as proportion
of Foxtail millet (Setaria italica) flour in mixed flour, fat content and
guar gum. The sugar, sodium chloride, sodium bicarbonates and
water were added in fixed proportion as 60, 1.0, 0.4 and 20% of
mixed flour weight, respectively. Optimum formulation obtained for
maximum spread ratio, fibre content, surface L-value, overall
acceptability and minimum breaking strength were 80% foxtail millet
flour in mixed flour, 42.8 % fat content and 0.05% guar gum.
Abstract: Series compensators have been used for many years,
to increase the stability and load ability of transmission line. They
compensate retarded or advanced volt drop of transmission lines
by placing advanced or retarded voltage in series with them to
compensate the effective reactance, which cause to increase load
ability of transmission lines. In this paper, two method of fuzzy
controller, based on power reference tracking and impedance
reference tracking have been developed on TCSC controller in
order to increase load ability and improving power oscillation
damping of system. In these methods, fire angle of thyristors are
determined directly through the special Rule-bases with the error
and change of error as the inputs. The simulation results of two
area four- machines power system show the good performance of
power oscillation damping in system. Comparison of this method
with classical PI controller shows the increasing speed of system
response in power oscillation damping.
Abstract: Component handling system is one of the important sub systems of Prototype Fast Breeder Reactor (PFBR) used for fuel handling. Core handling system is again a sub system of component handling system. Core handling system consists of in-vessel and ex-vessel subassembly handling. In-vessel core handling involves transfer arm, large rotatable plug and small rotatable plug operations. Modeling and simulation of in-vessel core handling is a part of development of Prototype Fast Breeder Reactor Operator Training Simulator. This paper deals with simulation and modeling of operations of transfer arm, large rotatable plug and small rotatable plug needed for in-vessel core handling. Process modeling was developed in house using platform independent Cµ code with OpenGL (Open Graphics Library). The control logic models and virtual panel were modeled using simulation tool.