Abstract: We proposed a new class of asymmetric turbo encoder for 3G systems that performs well in both “water fall" and “error floor" regions in [7]. In this paper, a modified (optimal) power allocation scheme for the different bits of new class of asymmetric turbo encoder has been investigated to enhance the performance. The simulation results and performance bound for proposed asymmetric turbo code with modified Unequal Power Allocation (UPA) scheme for the frame length, N=400, code rate, r=1/3 with Log-MAP decoder over Additive White Gaussian Noise (AWGN) channel are obtained and compared with the system with typical UPA and without UPA. The performance tests are extended over AWGN channel for different frame size to verify the possibility of implementation of the modified UPA scheme for the proposed asymmetric turbo code. From the performance results, it is observed that the proposed asymmetric turbo code with modified UPA performs better than the system without UPA and with typical UPA and it provides a coding gain of 0.4 to 0.52dB.
Abstract: One of the major parts of a jet engine is air intake,
which provides proper and required amount of air for the engine to
operate. There are several aerodynamic parameters which should be
considered in design, such as distortion, pressure recovery, etc. In
this research, the effects of lip ice accretion on pitot intake
performance are investigated. For ice accretion phenomenon, two
supervised multilayer neural networks (ANN) are designed, one for
ice shape prediction and another one for ice roughness estimation
based on experimental data. The Fourier coefficients of transformed
ice shape and parameters include velocity, liquid water content
(LWC), median volumetric diameter (MVD), spray time and
temperature are used in neural network training. Then, the subsonic
intake flow field is simulated numerically using 2D Navier-Stokes
equations and Finite Volume approach with Hybrid mesh includes
structured and unstructured meshes. The results are obtained in
different angles of attack and the variations of intake aerodynamic
parameters due to icing phenomenon are discussed. The results show
noticeable effects of ice accretion phenomenon on intake behavior.
Abstract: Excessive ductility demand on shorter piers is a
common problem for irregular bridges subjected to strong ground
motion. Various techniques have been developed to reduce the
likelihood of collapse of bridge due to failure of shorter piers. This
paper presents the new approach to improve the seismic behavior of
such bridges using Nitinol shape memory alloys (SMAs).
Superelastic SMAs have the ability to remain elastic under very large
deformation due to martensitic transformation. This unique property
leads to enhanced performance of controlled bridge compared with
the performance of the reference bridge. To evaluate the effectiveness
of the devices, nonlinear time history analysis is performed on a RC
single column bent highway bridge using a suite of representative
ground motions. The results show that this method is very effective in
limiting the ductility demand of shorter pier.
Abstract: Power transformers are among the most important and
expensive equipments in the electric power systems. Consequently
the transformer protection is an essential part of the system
protection. This paper presents a new method for locating
transformer winding faults such as turn-to-turn, turn-to-core, turn-totransformer
body, turn-to-earth, and high voltage winding to low
voltage winding. In this study the current and voltage signals of input
and output terminals of the transformer are measured, which the
Fourier transform of measured signals and harmonic analysis
determine the fault's location.
Abstract: In this paper, we present a cost-effective wireless
distributed load shedding system for non-emergency scenarios. In
power transformer locations where SCADA system cannot be used,
the proposed solution provides a reasonable alternative that combines
the use of microcontrollers and existing GSM infrastructure to send
early warning SMS messages to users advising them to proactively
reduce their power consumption before system capacity is reached
and systematic power shutdown takes place.
A novel communication protocol and message set have been
devised to handle the messaging between the transformer sites, where
the microcontrollers are located and where the measurements take
place, and the central processing site where the database server is
hosted. Moreover, the system sends warning messages to the endusers
mobile devices that are used as communication terminals. The
system has been implemented and tested via different experimental
results.
Abstract: Radio Frequency Identification (RFID) system is
looked upon as one of the top ten important technologies in the 20th
century and find its applications in many fields such as car industry.
The intelligent cars are one important part of this industry and always
try to find new and satisfied intelligent cars. The purpose of this
paper is to introduce an intelligent car with the based of RFID. By
storing the moving control commands such as turn right, turn left,
speed up and speed down etc. into the RFID tags beforehand and
sticking the tags on the tracks Car can read the moving control
commands from the tags and accomplish the proper actions.
Abstract: Face and facial expressions play essential roles in
interpersonal communication. Most of the current works on the facial
expression recognition attempt to recognize a small set of the
prototypic expressions such as happy, surprise, anger, sad, disgust
and fear. However the most of the human emotions are
communicated by changes in one or two of discrete features. In this
paper, we develop a facial expressions synthesis system, based on the
facial characteristic points (FCP's) tracking in the frontal image
sequences. Selected FCP's are automatically tracked using a crosscorrelation
based optical flow. The proposed synthesis system uses a
simple deformable facial features model with a few set of control
points that can be tracked in original facial image sequences.
Abstract: The LHP is a two-phase device with extremely high
effective thermal conductivity that utilizes the thermodynamic
pressure difference to circulate a cooling fluid. A thermodynamics
analytical model is developed to explore different parameters effects
on a Loop Heat Pipe (LHP).. The effects of pipe length, pipe
diameter, condenser temperature, and heat load are reported. As pipe
length increases and/or pipe diameter decreases, a higher temperature
is expected in the evaporator.
Abstract: This paper is devoted to predict laminar and turbulent
heating rates around blunt re-entry spacecraft at hypersonic
conditions. Heating calculation of a hypersonic body is normally
performed during the critical part of its flight trajectory. The
procedure is of an inverse method, where a shock wave is assumed,
and the body shape that supports this shock, as well as the flowfield
between the shock and body, are calculated. For simplicity the
normal momentum equation is replaced with a second order pressure
relation; this simplification significantly reduces computation time.
The geometries specified in this research, are parabola and ellipsoids
which may have conical after bodies. An excellent agreement is
observed between the results obtained in this paper and those
calculated by others- research. Since this method is much faster than
Navier-Stokes solutions, it can be used in preliminary design,
parametric study of hypersonic vehicles.
Abstract: In order to evaluation the effects of natural, biological
and chemical fertilizers on grain yield and chickpea quality, field
experiments were carried out in 2007 and 2008 growing seasons. In
this research the effects of different organic, chemical and biological
fertilizers were investigated on grain yield and quality of chickpea.
Experimental units were arranged in split-split plots based on
randomized complete blocks with three replications. The highest
amounts of yield and yield components were obtained in G1×N5
interaction. Significant increasing of N, P, K, Fe and Mg content in
leaves and grains emphasized on superiority of mentioned treatment
because each one of these nutrients has an approved role in
chlorophyll synthesis and photosynthesis ability of the crop. The
combined application of compost, farmyard manure and chemical
phosphorus (N5) had the best grain quality due to high protein, starch
and total sugar contents, low crude fiber and reduced cooking time.
Abstract: Circular knitting machine makes the fabric with more than two knitting tools. Variation of yarn tension between different knitting tools causes different loop length of stitches duration knitting process. In this research, a new intelligent method is applied to control loop length of stitches in various tools based on ideal shape of stitches and real angle of stitches direction while different loop length of stitches causes stitches deformation and deviation those of angle. To measure deviation of stitch direction against variation of tensions, image processing technique was applied to pictures of different fabrics with constant front light. After that, the rate of deformation is translated to needed compensation of loop length cam degree to cure stitches deformation. A fuzzy control algorithm was applied to loop length modification in knitting tools. The presented method was experienced for different knitted fabrics of various structures and yarns. The results show that presented method is useable for control of loop length variation between different knitting tools based on stitch deformation for various knitted fabrics with different fabric structures, densities and yarn types.
Abstract: Several researchers have proposed methods about
combination of Genetic Algorithm (GA) and Fuzzy Logic (the use of
GA to obtain fuzzy rules and application of fuzzy logic in
optimization of GA). In this paper, we suggest a new method in
which fuzzy decision making is used to improve the performance of
genetic algorithm. In the suggested method, we determine the alleles
that enhance the fitness of chromosomes and try to insert them to the
next generation.
In this algorithm we try to present an innovative vaccination in the
process of reproduction in genetic algorithm, with considering the
trade off between exploration and exploitation.
Abstract: The success of an electronic system in a System-on- Chip is highly dependent on the efficiency of its interconnection network, which is constructed from routers and channels (the routers move data across the channels between nodes). Since neither classical bus based nor point to point architectures can provide scalable solutions and satisfy the tight power and performance requirements of future applications, the Network-on-Chip (NoC) approach has recently been proposed as a promising solution. Indeed, in contrast to the traditional solutions, the NoC approach can provide large bandwidth with moderate area overhead. The selected topology of the components interconnects plays prime rule in the performance of NoC architecture as well as routing and switching techniques that can be used. In this paper, we present two generic NoC architectures that can be customized to the specific communication needs of an application in order to reduce the area with minimal degradation of the latency of the system. An experimental study is performed to compare these structures with basic NoC topologies represented by 2D mesh, Butterfly-Fat Tree (BFT) and SPIN. It is shown that Cluster mesh (CMesh) and MinRoot schemes achieves significant improvements in network latency and energy consumption with only negligible area overhead and complexity over existing architectures. In fact, in the case of basic NoC topologies, CMesh and MinRoot schemes provides substantial savings in area as well, because they requires fewer routers. The simulation results show that CMesh and MinRoot networks outperforms MESH, BFT and SPIN in main performance metrics.
Abstract: the effects of refining and alkaline chemicals on potential of recycling bleached chemical pulp of bagasse were investigated in this study. Recycling was done until three times. Handsheet properties such as, apparent density, light scattering coefficient, tear index, burst index, breaking length, and fold number according to TAPPI standard were measured. Water retention value also was used to considering the treatments during recycling. Refining enhanced the strength of recycled pulp by increasing fiber flexibility and swelling ability, whereas by applying chemical treatment didn't observe any improvement. The morphology of recycled fiber was considered with scanning electron microscopy (SEM).
Abstract: So much energy is used in high rise buildings to fulfill
the basic needs of users such as lighting and thermal comfort.
Malaysia has hot and humid climate, buildings especially high rise
buildings receive unnecessary solar radiation that cause more solar
heat gain. Energy use specially electricity consumption in high rise
buildings has increased. There have been growing concerns about
energy consumption and its effect on environment. Building, energy
and the environment are important issues that the designers should
consider to them. Self protected form is one of possible ways against
the impact of solar radiation in high rise buildings. The Energy
performance of building envelopes was investigated in term of the
Overall Thermal Transfer Value (OTTV ).In this paper, the amount
of OTTV reduction was calculated through OTTV Equations to
clear the effectiveness of self shading strategy on minimizing energy
consumption for cooling interior spaces in high rise buildings which
has considerable envelope areas against solar radiation. Also increasing
the optimum window area was investigated using self-shading
strategy in designing high rise buildings. As result, the significant
reduction in OTTV was shown based on WWR.In addition slight
increase was demonstrated in WWR that can influence on visible
comfort interior spaces.
Abstract: One of the most important parameters to develop and
manage urban areas is appropriate selection of land surface to
develop green spaces in these areas. In this study, in order to identify
the most appropriate sites and areas cultivated for ornamental species
in Jiroft, Landsat Enhanced Thematic Mapper Plus (ETM+) images
due to extract the most important effective climatic and adaphic
parameters for growth ornamental species were used. After geometric
and atmospheric corrections applied, to enhance accuracy of multi
spectral (XS) bands, the fusion of Landsat XS bands by IRS-1D
panchromatic band (PAN) was performed. After field sampling to
evaluate the correlation between different factors in surface soil
sampling location and different bands digital number (DN) of ETM+
sensor on the same points, correlation tables formed using the best
computational model and the map of physical and chemical
parameters of soil was produced. Then the accuracy of them was
investigated by using kappa coefficient. Finally, according to
produced maps, the best areas for cultivation of recommended
species were introduced.
Abstract: The hybridization of artificial immune system with
cellular automata (CA-AIS) is a novel method. In this hybrid model,
the cellular automaton within each cell deploys the artificial immune
system algorithm under optimization context in order to increase its
fitness by using its neighbor-s efforts. The hybrid model CA-AIS is
introduced to fix the standard artificial immune system-s weaknesses.
The credibility of the proposed approach is evaluated by simulations
and it shows that the proposed approach achieves better results
compared to standard artificial immune system.
Abstract: In this study, a mathematical model was proposed and
the accuracy of this model was assessed to predict the growth of
Pseudomonas aeruginosa and rhamnolipid production under nitrogen
limiting (sodium nitrate) fed-batch fermentation. All of the
parameters used in this model were achieved individually without
using any data from the literature.
The overall growth kinetic of the strain was evaluated using a
dual-parallel substrate Monod equation which was described by
several batch experimental data. Fed-batch data under different
glycerol (as the sole carbon source, C/N=10) concentrations and feed
flow rates were used to describe the proposed fed-batch model and
other parameters. In order to verify the accuracy of the proposed
model several verification experiments were performed in a vast
range of initial glycerol concentrations. While the results showed an
acceptable prediction for rhamnolipid production (less than 10%
error), in case of biomass prediction the errors were less than 23%. It
was also found that the rhamnolipid production by P. aeruginosa was
more sensitive at low glycerol concentrations.
Based on the findings of this work, it was concluded that the
proposed model could effectively be employed for rhamnolipid
production by this strain under fed-batch fermentation on up to 80 g l-
1 glycerol.
Abstract: Tip vortex cavitation is one of well known patterns of
cavitation phenomenon which occurs in axial pumps. This pattern of
cavitation occurs due to pressure difference between the pressure and
suction sides of blades of an axial pump. Since the pressure in the
pressure side of the blade is higher than the pressure in its suction
side, thus a very small portion of liquid flow flows back from
pressure side to the suction side. This fact is cause of tip vortex
cavitation and gap cavitation that may occur in axial pumps. In this
paper the results of our experimental investigation about movement
of tip vortex cavitation along blade edge due to reduction of pump
flow rate in an axial pump is reported. Results show that reduction of
pump flow rate in conjunction with increasing of outlet pressure
causes movement of tip vortex cavitation along blade edge towards
the blade tip. Results also show that by approaching tip vortex
cavitation to the blade tip, vortex tip pattern of cavitation replaces
with a cavitation phenomenon on the blade tip. Furthermore by
further reduction of pump flow rate and increasing of outlet pressure,
an unstable cavitation phenomenon occurs between each blade
leading edge and the next blade trailing edge.
Abstract: Selective oxidation of H2S to elemental sulfur in a
fixed bed reactor over newly synthesized alumina nanocatalysts was
physio-chemically investigated and results compared with a
commercial Claus catalyst. Amongst these new materials, Al2O3-
supported sodium oxide prepared with wet chemical technique and
Al2O3 nanocatalyst prepared with spray pyrolysis method were the
most active catalysts for selective oxidation of H2S to elemental
sulfur. Other prepared nanocatalysts were quickly deactivated,
mainly due to the interaction with H2S and conversion into sulfides.