Abstract: Dual motor drives fed by single inverter is
purposely designed to reduced size and cost with respect to
single motor drives fed by single inverter. Previous researches
on dual motor drives only focus on the modulation and the
averaging techniques. Only a few of them, study the
performance of the drives based on different speed controller
other than Proportional and Integrator (PI) controller. This
paper presents a detailed comparative study on fuzzy rule-base
in Fuzzy Logic speed Controller (FLC) for Dual Permanent
Magnet Synchronous Motor (PMSM) drives. Two fuzzy speed
controllers which are standard and simplified fuzzy speed
controllers are designed and the results are compared and
evaluated. The standard fuzzy controller consists of 49 rules
while the proposed controller consists of 9 rules determined by
selecting the most dominant rules only. Both designs are
compared for wide range of speed and the robustness of both
controllers over load disturbance changes is tested to
demonstrate the effectiveness of the simplified/reduced rulebase.
Abstract: In [4], Kipnis and Shamir have cryptanalised
a version of HFE of degree 2. In this paper, we describe the
generalization of this attack of HFE of degree more than 2.
We are based on Fourier Transformation to acheive partially
this attack.
Abstract: In the present work, we have developed a symmetric electrochemical capacitor based on the nanostructured iron oxide (Fe3O4)-activated carbon (AC) nanocomposite materials. The physical properties of the nanocomposites were characterized by Scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis. The electrochemical performances of the composite electrode in 1.0 M Na2SO3 and 1.0 M Na2SO4 aqueous solutions were evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The composite electrode with 4 wt% of iron oxide nanomaterials exhibits the highest capacitance of 86 F/g. The experimental results clearly indicate that the incorporation of iron oxide nanomaterials at low concentration to the composite can improve the capacitive performance, mainly attributed to the contribution of the pseudocapacitance charge storage mechanism and the enhancement on the effective surface area of the electrode. Nevertheless, there is an optimum threshold on the amount of iron oxide that needs to be incorporated into the composite system. When this optimum threshold is exceeded, the capacitive performance of the electrode starts to deteriorate, as a result of the undesired particle aggregation, which is clearly indicated in the SEM analysis. The electrochemical performance of the composite electrode is found to be superior when Na2SO3 is used as the electrolyte, if compared to the Na2SO4 solution. It is believed that Fe3O4 nanoparticles can provide favourable surface adsorption sites for sulphite (SO3 2-) anions which act as catalysts for subsequent redox and intercalation reactions.
Abstract: In this study, a 3D combustion chamber was simulated
using FLUENT 6.32. Aim to obtain detailed information on
combustion characteristics and _ nitrogen oxides in the furnace and
the effect of oxygen enrichment in a combustion process. Oxygenenriched
combustion is an effective way to reduce emissions. This
paper analyzes NO emission, including thermal NO and prompt NO.
Flow rate ratio of air to fuel is varied as 1.3, 3.2 and 5.1 and the
oxygen enriched flow rates are 28, 54 and 68 lit/min. The 3D
Reynolds Averaged Navier Stokes (RANS) equations with standard
k-ε turbulence model are solved together by Fluent 6.32 software.
First order upwind scheme is used to model governing equations and
the SIMPLE algorithm is used as pressure velocity coupling. Results
show that for AF=1.3, increase the oxygen flow rate of oxygen
reduction in NO emissions is Lance. Moreover, in a fixed oxygen
enrichment condition, increasing the air to fuel ratio will increase the
temperature peak, but not the NO emission rate. As a result, oxygen
enrichment can reduce the NO emission at this kind of furnace in low
air to fuel rates.
Abstract: This study investigated the ecological effects of
particulate pollution from a cement factory on the vegetation in the
western Mediterranean coastal desert of Egypt. Variations in
vegetation, soil chemical characters, and some responses of Atriplex
halimus, as a dominant species in the study area, were investigated in
some sites located in different directions from the cement factory
between Burg El-Arab in the east and El-Hammam in the west. The
results showed an obvious decrease in vegetation diversity, in
response to cement-kiln dust pollution, that accompanied by a high
dominance attributed to the high contribution of Atriplex halimus.
Annual species were found to be more sensitive to cement dust
pollution as they all failed to persist in highly disturbed sites. It is
remarkable that cover and phytomass of Atriplex halimus were
increased greatly in response to cement dust pollution, and this was
accompanied by a reduction in the mature seeds and leaf-area of the
plant. The few seeds of the affected individuals seemed to be more
fertile and attained higher germination percentages and exhibited
hardening against drought stress.
Abstract: The paper presents a new system for the automat
control of the aircrafts- flight in lateral plane using the cinematic
model and the dynamic inversion. Starting from the equations of the
aircrafts- lateral movement, the authors use two axes systems and
obtained a control law that cancels the lateral deviation of the flying
objects from the runway line. This system makes the aircrafts-
direction angle to follow the direction angle of the runway line.
Simulations in Matlab/Simulink have been done for different
aircraft-s initial points and direction angles. The inconvenience of
this system is the long duration of the “transient regime". That is why
this system can be used independently, but the results are not very
good; thus, it can be a part (subsystem) of other systems. The main
system that cancels the lateral deviation from the runway line is
based on dynamic inversion and uses, as subsystem, the control
system for the lateral movement using the cinematic model. Using
complex Matlab/Simulink models, the authors obtained the time
evolution of the direction angle and the time evolution of the aircraft
lateral deviation with respect to the runway line, for different values
of the initial direction angle and for different wind types. The system
has a very good behavior for all initial direction angles and wind
types.
Abstract: UML is a collection of notations for capturing a software system specification. These notations have a specific syntax defined by the Object Management Group (OMG), but many of their constructs only present informal semantics. They are primarily graphical, with textual annotation. The inadequacies of standard UML as a vehicle for complete specification and implementation of real-time embedded systems has led to a variety of competing and complementary proposals. The Real-time UML profile (UML-RT), developed and standardized by OMG, defines a unified framework to express the time, scheduling and performance aspects of a system. We present in this paper a framework approach aimed at deriving a complete specification of a real-time system. Therefore, we combine two methods, a semiformal one, UML-RT, which allows the visual modeling of a realtime system and a formal one, CSP+T, which is a design language including the specification of real-time requirements. As to show the applicability of the approach, a correct design of a real-time system with hard real time constraints by applying a set of mapping rules is obtained.
Abstract: A new secure knapsack cryptosystem based on the
Merkle-Hellman public key cryptosystem will be proposed in this
paper. Although it is common sense that when the density is low, the
knapsack cryptosystem turns vulnerable to the low-density attack. The
density d of a secure knapsack cryptosystem must be larger than
0.9408 to avoid low-density attack. In this paper, we investigate a
new Permutation Combination Algorithm. By exploiting this
algorithm, we shall propose a novel knapsack public-key cryptosystem.
Our proposed scheme can enjoy a high density to avoid the
low-density attack. The density d can also exceed 0.9408 to avoid
the low-density attack.
Abstract: The risk of water erosion is one of the main
environmental concerns in the southern Mediterranean regions. Thus,
quantification of soil loss is an important issue for soil and water
conservation managers. The objective of this paper is to examine the
applicability of the Soil and Water Assessment Tool (SWAT) model
in The Sarrath river catchment, North of Tunisia, and to identify the
most vulnerable areas in order to help manager implement an
effective management program. The spatial analysis of the results
shows that 7 % of the catchment experiences very high erosion risk,
in need for suitable conservation measures to be adopted on a priority
basis. The spatial distribution of erosion risk classes estimated 3%
high, 5,4% tolerable, and 84,6% low. Among the 27 delineated subcatchments
only 4 sub-catchments are found to be under high and
very high soil loss group, two sub-catchments fell under moderate
soil loss group, whereas other sub-catchments are under low soil loss
group.
Abstract: The amount of the information being churned out by the field of biology has jumped manifold and now requires the extensive use of computer techniques for the management of this information. The predominance of biological information such as protein sequence similarity in the biological information sea is key information for detecting protein evolutionary relationship. Protein sequence similarity typically implies homology, which in turn may imply structural and functional similarities. In this work, we propose, a learning method for detecting remote protein homology. The proposed method uses a transformation that converts protein sequence into fixed-dimensional representative feature vectors. Each feature vector records the sensitivity of a protein sequence to a set of amino acids substrings generated from the protein sequences of interest. These features are then used in conjunction with support vector machines for the detection of the protein remote homology. The proposed method is tested and evaluated on two different benchmark protein datasets and it-s able to deliver improvements over most of the existing homology detection methods.
Abstract: In this paper, we explore a new scheme for filtering spoofed packets (DDOS attack) which is a combination of path fingerprint and client puzzle concepts. In this each IP packet has a unique fingerprint is embedded that represents, the route a packet has traversed. The server maintains a mapping table which contains the client IP address and its corresponding fingerprint. In ingress router, client puzzle is placed. For each request, the puzzle issuer provides a puzzle which the source has to solve. Our design has the following advantages over prior approaches, 1) Reduce the network traffic, as we place a client puzzle at the ingress router. 2) Mapping table at the server is lightweight and moderate.
Abstract: We propose an all optical flip-flop circuit composedof two Silicon-on-insulator microring resonators coupled to straightwaveguides by exploiting the optical bistability behavior due to thenonlinear Kerr effect. We used the transfer matrix analysis toinvestigate continuous wave propagation through microrings, as wellwe considered the nonlinear switching characteristics of an opticaldevice using a double-coupler silicon ring resonator in presence ofthe Kerr nonlinearity, thus obtaining the bistability behavior of theoutput port, the drop port and also inside the silicon microringresonator. It is shown that the bistability behavior depends on thecontrol of the input wavelength.KeywordsAll optical flip-flops, Kerr effect, microringresonator, optical bistability.
Abstract: Bacillus subtilis strain LB5 produced lipopeptide
antibiotic iturin A-2 in liquid medium. Crude extract
from cell-free supernatant of B. subtilis cultivated broth extracted
with n-butanol showed antifungal activity to conidial germination of
Colletotrichum gloeosporioides. The germination of conidia was
completely inhibited by crude extract. The ultrastructure of conidia
after treated with crude extract was found an accumulation of vesiclelike
material between cell wall and plasma membrane while this
accumulation was not observed in untreated and germinated conidia.
Besides, the cell wall was not affected by crude extract.
Abstract: This study carried out to determine the effect of plant
densities on some agronomic characteristics of four safflower cultivars in spring planting. The experiment was conducted at Yazd,
Iran- using a factorial in a randomized complete block design with four replications. Cultivars were including Arak, IL, Asteria and Local and plant densities were 10, 13.3, 20 and 40 plant/m2. Number
of seeds/head, number of heads/plant, HI, 1000-seed weight and seed yield significantly decreased as planting density increased. With increasing planting density, LAI, plant height, first branch height and
biological yield increased. The highest seed yield was obtained in 13.3 plant/m2 (2167 kg/ha). There were significant differences
between cultivars. Local cv. had higher seed yield than the other cultivars mainly due to higher heads/plant and seeds/head.
Abstract: Hydrogen is regarded to play an important role in
future energy systems because it can be produced from abundant
resources and its combustion only generates water. The disposal of
waste tyres is a major problem in environmental management
throughout the world. The use of waste materials as a source of
hydrogen is particularly of interest in that it would also solve a waste
treatment problem. There is much interest in the use of alternative
feedstocks for the production of hydrogen since more than 95% of
current production is from fossil fuels. The pyrolysis of waste tyres
for the production of liquid fuels, activated carbons and gases has
been extensively researched. However, combining pyrolysis with
gasification is a novel process that can gasify the gaseous products
from pyrolysis. In this paper, an experimental investigation into the
production of hydrogen and other gases from the bench scale
pyrolysis-gasification of tyres has been investigated. Experiments
were carried using a two stage system consisting of pyrolysis of the
waste tyres followed by catalytic steam gasification of the evolved
gases and vapours in a second reactor. Experiments were conducted
at a pyrolysis temperature of 500 °C using Ni/Al2O3 as a catalyst. The
results showed that there was a dramatic increase in gas yield and the
potential H2 production when the gasification temperature was
increased from 600 to 900 oC. Overall, the process showed that high
yields of hydrogen can be produced from waste tyres.
Abstract: This article introduces the actual problem that is а
study of proposed by the authors Hydrocele ointment in amino acids’
metabolism of cows’ blood in inflammation of traumatic origin.
Hydrocele ointment has shown a positive effect on inflammatory
process and amino acids’ metabolism of animals treated with the
drug. Amino acid levels reached physiological parameters on the 10th
day after treatment; in the control group this parameter was higher
than normal.
Abstract: The present work deals with the calculation of
transport properties of Hg0.8Cd0.2Te (MCT) semiconductor in
degenerate case. Due to their energy-band structure, this material
becomes degenerate at moderate doping densities, which are around
1015 cm-3, so that the usual Maxwell-Boltzmann approximation is
inaccurate in the determination of transport parameters. This problem
is faced by using Fermi-Dirac (F-D) statistics, and the non-parabolic
behavior of the bands may be approximated by the Kane model. The
Monte Carlo (MC) simulation is used here to determinate transport
parameters: drift velocity, mean energy and drift mobility versus
electric field and the doped densities. The obtained results are in
good agreement with those extracted from literature.
Abstract: Main goal of preventive healthcare problems are at
decreasing the likelihood and severity of potentially life-threatening
illnesses by protection and early detection. The levels of
establishment and staffing costs along with summation of the travel
and waiting time that clients spent are considered as objectives
functions of the proposed nonlinear integer programming model. In
this paper, we have proposed a bi-objective mathematical model for
designing a network of preventive healthcare facilities so as to
minimize aforementioned objectives, simultaneously. Moreover, each
facility acts as M/M/1 queuing system. The number of facilities to be
established, the location of each facility, and the level of technology
for each facility to be chosen are provided as the main determinants
of a healthcare facility network. Finally, to demonstrate performance
of the proposed model, four multi-objective decision making
techniques are presented to solve the model.
Abstract: The security of computer networks plays a strategic
role in modern computer systems. Intrusion Detection Systems (IDS)
act as the 'second line of defense' placed inside a protected
network, looking for known or potential threats in network traffic
and/or audit data recorded by hosts. We developed an Intrusion
Detection System using LAMSTAR neural network to learn patterns
of normal and intrusive activities, to classify observed system
activities and compared the performance of LAMSTAR IDS with
other classification techniques using 5 classes of KDDCup99 data.
LAMSAR IDS gives better performance at the cost of high
Computational complexity, Training time and Testing time, when
compared to other classification techniques (Binary Tree classifier,
RBF classifier, Gaussian Mixture classifier). we further reduced the
Computational Complexity of LAMSTAR IDS by reducing the
dimension of the data using principal component analysis which in
turn reduces the training and testing time with almost the same
performance.
Abstract: The theoretical investigation is carried out to describe
the effect of increase of pressure waves amplitude in clean and bubbly liquid. The goal of the work is to capture the regime of multiple magnification of acoustic and shock waves in the liquid,
which enables to get appropriate conditions to enlarge collapses of
micro-bubbles. The influence of boundary conditions and frequency
of the governing acoustic field is studied for the case of the
cylindrical acoustic resonator. It has been observed the formation of
standing waves with large amplitude at resonant frequencies. The
interaction of the compression wave with gas and vapor bubbles is
investigated for the convergent channel. It is shown theoretically that
the chemical reactions, which occur inside gas bubbles, provide additional impulse to the wave, that affect strongly on the collapses
of the vapor bubbles