Abstract: The thermal, epithermal and fast fluxes were
calculated for three irradiation channels at Egypt Second Research
Reactor (ETRR-2) using CITVAP code. The validity of the
calculations was verified by experimental measurements. There are
some deviations between measurements and calculations. This is due
to approximations in the calculation models used, homogenization of
regions, condensation of energy groups and uncertainty in nuclear
data used. Neutron flux data for the three irradiation channels are
now available. This would enable predicting the irradiation
conditions needed for future radioisotope production.
Abstract: Several studies have shown the association between
ambient particulate matter (PM) and adverse health effects and
climate change, thus highlighting the need to limit the anthropogenic
sources of PM. PM Exposure is commonly monitored as mass
concentration of PM10 (particle aerodynamic diameter < 10μm) or
PM2.5 (particle aerodynamic diameter < 2.5μm), although increasing
toxicity with decreasing aerodynamic diameter has been reported due
to increased surface area and enhanced chemical reactivity with other
species. Additionally, the light scattering properties of PM increases
with decreasing size. Hence, it is important to study the chemical
characterization of finer fraction of the particulate matter and to
identify their sources so that they can be controlled appropriately to a
large extent at the sources before reaching to the receptors.
Abstract: The power consumption of an Optical Packet Switch
equipped with SOA technology based Spanke switching fabric is
evaluated. Sophisticated analytical models are introduced to evaluate
the power consumption versus the offered traffic, the main
switch parameters, and the used device characteristics. The impact
of Amplifier Spontaneous Emission (ASE) noise generated by a
transmission system on the power consumption is investigated. As
a matter of example for 32×32 switches supporting 64 wavelengths
and offered traffic equal to 0,8, the average energy consumption per
bit is 5, 07 · 10-2 nJ/bit and increases if ASE noise introduced by
the transmission systems is increased.
Abstract: Transient simulation of power electronic circuits is of
considerable interest to the designer. The switching nature of the
devices used permits development of specialized algorithms which
allow a considerable reduction in simulation time compared to
general purpose simulation algorithms. This paper describes a
method used to simulate a power electronic circuits using the
SIMULINK toolbox within MATLAB software. Theoretical results
are presented provides the basis of transient analysis of a power
electronic circuits.
Abstract: Sedimentation is a hydraulic phenomenon that is
emerging as a serious challenge in river engineering. When the flow
reaches a certain state that gather potential energy, it shifts the
sediment load along channel bed. The transport of such materials can
be in the form of suspended and bed loads. The movement of these
along the river course and channels and the ways in which this could
influence the water intakes is considered as the major challenges for
sustainable O&M of hydraulic structures. This could be very serious
in arid and semi-arid regions like Iran, where inappropriate watershed
management could lead to shifting a great deal of sediments into the
reservoirs and irrigation systems. This paper aims to investigate
sedimentation in the Western Canal of Dez Diversion Weir in Iran,
identifying factors which influence the process and provide ways in
which to mitigate its detrimental effects by using the SHARC
Software.
For the purpose of this paper, data from the Dezful water authority
and Dezful Hydrometric Station pertinent to a river course of about 6
Km were used.
Results estimated sand and silt bed loads concentrations to be 193
ppm and 827ppm respectively. Given the available data on average
annual bed loads and average suspended sediment loads of 165ppm
and 837ppm, there was a significant statistical difference (16%)
between the sand grains, whereas no significant difference (1.2%)
was find in the silt grain sizes. One explanation for such finding
being that along the 6 Km river course there was considerable
meandering effects which explains recent shift in the hydraulic
behavior along the stream course under investigation. The sand
concentration in downstream relative to present state of the canal
showed a steep descending curve. Sediment trapping on the other
hand indicated a steep ascending curve. These occurred because the
diversion weir was not considered in the simulation model.
Abstract: In this paper, we proposed an efficient data
compression strategy exploiting the multi-resolution characteristic of
the wavelet transform. We have developed a sensor node called
“Smart Sensor Node; SSN". The main goals of the SSN design are
lightweight, minimal power consumption, modular design and robust
circuitry. The SSN is made up of four basic components which are a
sensing unit, a processing unit, a transceiver unit and a power unit.
FiOStd evaluation board is chosen as the main controller of the SSN
for its low costs and high performance. The software coding of the
implementation was done using Simulink model and MATLAB
programming language. The experimental results show that the
proposed data compression technique yields recover signal with good
quality. This technique can be applied to compress the collected data
to reduce the data communication as well as the energy consumption
of the sensor and so the lifetime of sensor node can be extended.
Abstract: In this paper, Lattice Boltzmann Method (LBM) is used to study laminar flow with mixed convection heat transfer inside a two-dimensional inclined lid-driven rectangular cavity with aspect ratio AR = 3. Bottom wall of the cavity is maintained at lower temperature than the top lid, and its vertical walls are assumed insulated. Top lid motion results in fluid motion inside the cavity. Inclination of the cavity causes horizontal and vertical components of velocity to be affected by buoyancy force. To include this effect, calculation procedure of macroscopic properties by LBM is changed and collision term of Boltzmann equation is modified. A computer program is developed to simulate this problem using BGK model of lattice Boltzmann method. The effects of the variations of Richardson number and inclination angle on the thermal and flow behavior of the fluid inside the cavity are investigated. The results are presented as velocity and temperature profiles, stream function contours and isotherms. It is concluded that LBM has good potential to simulate mixed convection heat transfer problems.
Abstract: This paper presents a methodology for operational and
economic characteristics based evaluation and selection of a power
plant using Graph theoretic approach. A universal evaluation index
on the basis of Operational and economics characteristics of a plant is
proposed which evaluates and ranks the various types of power plants.
The index thus obtained from the pool of operational characteristics
of the power plant attributes Digraph. The Digraph is developed
considering Operational and economics attributes of the power plants
and their relative importance for their smooth operation, installation
and commissioning and prioritizing their selection. The sensitivity
analysis of the attributes towards the objective has also been carried
out in order to study the impact of attributes over the desired outcome
i.e. the universal operational-economics index of the power plant.
Abstract: This paper presents a method for the optimal
allocation of Distributed generation in distribution systems. In this
paper, our aim would be optimal distributed generation allocation for
voltage profile improvement and loss reduction in distribution
network. Genetic Algorithm (GA) was used as the solving tool,
which referring two determined aim; the problem is defined and
objective function is introduced. Considering to fitness values
sensitivity in genetic algorithm process, there is needed to apply load
flow for decision-making. Load flow algorithm is combined
appropriately with GA, till access to acceptable results of this
operation. We used MATPOWER package for load flow algorithm
and composed it with our Genetic Algorithm. The suggested method
is programmed under MATLAB software and applied ETAP
software for evaluating of results correctness. It was implemented on
part of Tehran electricity distributing grid. The resulting operation of
this method on some testing system is illuminated improvement of
voltage profile and loss reduction indexes.
Abstract: Almost all universities include some form of assignment in their courses. The assignments are either carried out in either in groups or individually. To effectively manage these submitted assignments, a well-designed assignment submission system is needed, hence the need for an online assignment submission system to facilitate the distribution, and collection of assignments on due dates. The objective of such system is to facilitate interaction of lecturers and students for assessment and grading purposes. The aim of this study was to create a web based online assignment submission system for University of Mauritius. The system was created to eliminate the traditional process of giving an assignment and collecting the answers for the assignment. Lecturers can also create automated assessment to assess the students online. Moreover, the online submission system consists of an automatic mailing system which acts as a reminder for students about the deadlines of the posted assignments. System was tested to measure its acceptance rate among both student and lecturers.
Abstract: In this paper, a new approach for target recognition based on the Empirical mode decomposition (EMD) algorithm of Huang etal. [11] and the energy tracking operator of Teager [13]-[14] is introduced. The conjunction of these two methods is called Teager-Huang analysis. This approach is well suited for nonstationary signals analysis. The impulse response (IR) of target is first band pass filtered into subsignals (components) called Intrinsic mode functions (IMFs) with well defined Instantaneous frequency (IF) and Instantaneous amplitude (IA). Each IMF is a zero-mean AM-FM component. In second step, the energy of each IMF is tracked using the Teager energy operator (TEO). IF and IA, useful to describe the time-varying characteristics of the signal, are estimated using the Energy separation algorithm (ESA) algorithm of Maragos et al .[16]-[17]. In third step, a set of features such as skewness and kurtosis are extracted from the IF, IA and IMF energy functions. The Teager-Huang analysis is tested on set of synthetic IRs of Sonar targets with different physical characteristics (density, velocity, shape,? ). PCA is first applied to features to discriminate between manufactured and natural targets. The manufactured patterns are classified into spheres and cylinders. One hundred percent of correct recognition is achieved with twenty three echoes where sixteen IRs, used for training, are free noise and seven IRs, used for testing phase, are corrupted with white Gaussian noise.
Abstract: A composite made of plasma functionalized multiwall
carbon nanotubes (MWNTs) coated with SnO2 was synthesized by
sonochemical precipitation method. Thick layer of this
nanocomposite material was used as ethanol sensor at low
temperatures. The composite sensitivity for ethanol has increased by
a factor of 2 at room temperature and by a factor of 13 at 250°C in
comparison to that of pure SnO2. SEM image of nanocomposite
material showed MWNTs were embedded in SnO2 matrix and also a
higher surface area was observed in the presence of functionalized
MWNTs. Greatly improved sensitivity of the composite material to
ethanol can be attributed to new gas accessing passes through
MWNTs and higher specific surface area.
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: 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: 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.