Abstract: The performance of ground to deep space optical
communication systems is degraded by distortion of the beam as it
propagates through the turbulent atmosphere. Turbulence causes
fluctuations in the intensity of the received signal which ultimately
affects the acquisition time required to acquire and locate the spaceborne
target using narrow laser beam. In this paper, performance of
free-space optical (FSO) communication system in atmospheric
turbulence has been analyzed in terms of acquisition time for
coherent and non-coherent modulation schemes. Numerical results
presented in graphical and tabular forms show that the acquisition
time increases with the increase in turbulence level. This is true for
both schemes. The BPSK has lowest acquisition time among all
schemes. In non-coherent schemes, M-PPM performs better than the
other schemes. With the increase in M, acquisition time becomes
lower, but at the cost of increase in system complexity.
Abstract: Dissolved gas analysis has been accepted as a sensitive, informative and reliable technique for incipient faults detection in power transformers and is widely used. In the last few years this method, which has been recommended by IEEE Power & Energy society, has been applied for fault detection in load tap changers. Regarding the critical role of load tap changers in electrical network and essential of catastrophic failures prevention, it is necessary to choose "condition based preventative maintenance strategy" which leads to reduction in costs, the number of unnecessary visits as well as the probability of interruptions and also increment in equipment reliability. In current work, considering the condition based preventative maintenance strategy, condition assessment of an Elin tap changer was carried out using dissolved gas analysis.
Abstract: In space during functioning, a satellite will be heated
up due to the behavior of its components such as power electronics.
In order to prevent problems in the satellite, this heat has to be
released in space thanks to the cooling system. This system consists
of a loop heat pipe (LHP), in which a fluid streams through an
evaporator and a condenser. In the evaporator, the fluid captures the
heat from the satellite and evaporates. Then it flows to the condenser
where it releases the heat and it condenses. In this project, the two
mains parts of a cooling system are studied: the evaporator and the
condenser. The study of the diphasic loop was done starting from
digital simulations carried out under Matlab and Femlab.
Abstract: In Egypt, the concept of Asset Management (AM) is
new; however, the need for applying it has become crucial because
deteriorating or losing an asset is unaffordable in a developing
country like Egypt. Therefore the current study focuses on
educational buildings as one of the most important assets regarding
planning, building, operating and maintenance expenditures. The
main objective of this study is to develop a SAMF for educational
buildings in Egypt. The General Authority for Educational Buildings
(GAEB) was chosen as a case study of the current research as it
represents the biggest governmental organization responsible for
planning, operating and maintaining schools in Egypt. To achieve the
research objective, structured interviews were conducted with senior
managers of GAEB using a pre designed questionnaire to explore the
current practice of AM. Gab analysis technique was applied against
best practices compounded from a vast literature review to identify
gaps between current practices and the desired one. The previous
steps mainly revealed; limited knowledge about strategic asset
management, no clear goals, no training, no real risk plan and lack of
data, technical and financial resources. Based on the findings, a
SAMF for GAEB was introduced and Framework implementation
steps and assessment techniques were explained in detail.
Abstract: Studies were carried out on the comparative study of the production of Avicelase enzyme using sugarcane bagasse-SCB in two different statuses (i.e. treated and untreated SCB) by thermophilic Geobacillus stearothermophilus at 50ºC. Only four thermophilic bacterial isolates were isolated and assayed for Avicelase production using UntSCB and TSCB. Only one isolate selected as most potent and identified as G. stearothermophilus used in this study. A specific endo-β-1,4-D-glucanase (Avicelase EC 3.2.1.91) was partially purified from a thermophilic bacterial strain was isolated from different soil samples when grown on cellulose enrichment SCB substrate as the sole carbon source. Results shown that G. stearothermophilus was the better Avicelase producer strain. Avicelase had an optimum pH and temperature 7.0 and 50ºC for both UntSCB and TSCB and exhibited good pH stability between "5-8" and "4-9", however, good temperature stability between (30-80ºC) for UntSCB and TSCB, respectively. Other factors affecting the production of Avicelase were compared (i.e. SCB concentration, inoculum size and different incubation periods), all results observed and obtained were revealed that the TSCB was exhibited maximal enzyme activity in comparison with the results obtained from UntSCB, so, the TSCB was enhancing the Avicelase production.
Abstract: At present the process of formation of corporate
values in Kazakh universities is under the influence of a whole range
of socio-economic and cultural changes: on the one hand universities
must maintain and transmit traditional cultural values of education,
on the other, to improve quality of service and to involve young
people to science, providing thus own competitiveness. Thus, this
article presents some results of two cycles of sociological research
conducted in 2012 and aimed at identifying possible ways to
popularize science and readiness to participate of youth in given
activities, expectations of young scientists and the prospects of future
development of the Kazakh science.
Abstract: Finding suitable non-supersingular elliptic curves for
pairing-based cryptosystems becomes an important issue for the
modern public-key cryptography after the proposition of id-based
encryption scheme and short signature scheme. In previous work
different algorithms have been proposed for finding such elliptic
curves when embedding degree k ∈ {3, 4, 6} and cofactor h ∈ {1, 2, 3,
4, 5}. In this paper a new method is presented to find more
non-supersingular elliptic curves for pairing-based cryptosystems with
general embedding degree k and large values of cofactor h. In
addition, some effective parameters of these non-supersingular elliptic
curves are provided in this paper.
Abstract: Turbulence of the incoming wind field is of paramount
importance to the dynamic response of civil engineering structures. Hence reliable stochastic models of the turbulence should be available from which time series can be generated for dynamic response and
structural safety analysis. In the paper an empirical cross spectral
density function for the along-wind turbulence component over the wind field area is taken as the starting point. The spectrum is spatially
discretized in terms of a Hermitian cross-spectral density matrix for the turbulence state vector which turns out not to be positive
definite. Since the succeeding state space and ARMA modelling of
the turbulence rely on the positive definiteness of the cross-spectral
density matrix, the problem with the non-positive definiteness of such
matrices is at first addressed and suitable treatments regarding it are proposed. From the adjusted positive definite cross-spectral density
matrix a frequency response matrix is constructed which determines the turbulence vector as a linear filtration of Gaussian white noise.
Finally, an accurate state space modelling method is proposed which allows selection of an appropriate model order, and estimation of a state space model for the vector turbulence process incorporating its phase spectrum in one stage, and its results are compared with a conventional ARMA modelling method.
Abstract: In this study integral form and new recursive formulas
for Favard constants and some connected with them numeric and
Fourier series are obtained. The method is based on preliminary
integration of Fourier series which allows for establishing finite
recursive representations for the summation. It is shown that the
derived recursive representations are numerically more effective than
known representations of the considered objects.
Abstract: Urban problems are problems of organized complexity. Thus, many models and scientific methods to resolve urban problems are failed. This study is concerned with proposing of a fuzzy system driven approach for classification and solving urban problems. The proposed study investigated mainly the selection of the inputs and outputs of urban systems for classification of urban problems. In this research, five categories of urban problems, respect to fuzzy system approach had been recognized: control, polytely, optimizing, open and decision making problems. Grounded Theory techniques were then applied to analyze the data and develop new solving method for each category. The findings indicate that the fuzzy system methods are powerful processes and analytic tools for helping planners to resolve urban complex problems. These tools can be successful where as others have failed because both incorporate or address uncertainty and risk; complexity and systems interacting with other systems.
Abstract: Tufting carpet is a very suitable substrate for growing
microorganism such as pathogenic microbes, due to the direct touch
with human body, long washing periods and laying on the floor; in
fact there are 3 major problems: To risk human health, Prepare bad
odors and Destruction of the products.. In the presented research, for
investigation of presence most common microbes on polyester
tufting, first goods laid in a public place (in the corridor fair) for 30
days and the existence of some microbes were investigate on it with
two methods of enrichment in nutrient environments such as
thioglycolate and noutrunt brath, and shake the dust off the polyester
tufting onto cultivation mediums such as blood agar and noutrunt
agar. After the microorganism colonics are grown, the colonies were
separated and six microbial tests such as cataloes and sitrat were
carried out in five phases on the colonics for identifying the varieties
of bacteria. As a result of tests, 5 type of bacteria, such as
Escherichia coli, staphylococcus saprophytic as were identified. Each
of the mentioned bacteria can be seriously harmful for the heath of
human.
Abstract: In this paper we discuss the development of an Augmented Reality (AR) - based scientific visualization system prototype that supports identification, localisation, and 3D visualisation of oil leakages sensors datasets. Sensors generates significant amount of multivariate datasets during normal and leak situations. Therefore we have developed a data model to effectively manage such data and enhance the computational support needed for the effective data explorations. A challenge of this approach is to reduce the data inefficiency powered by the disparate, repeated, inconsistent and missing attributes of most available sensors datasets. To handle this challenge, this paper aim to develop an AR-based scientific visualization interface which automatically identifies, localise and visualizes all necessary data relevant to a particularly selected region of interest (ROI) along the virtual pipeline network. Necessary system architectural supports needed as well as the interface requirements for such visualizations are also discussed in this paper.
Abstract: This paper proposes a model of adding relations between
members of the same level in a pyramid organization structure
which is a complete K-ary tree such that the communication of
information between every member in the organization becomes the
most efficient. When edges between one node and every other node
with the same depth N in a complete K-ary tree of height H are
added, an optimal depth N* = H is obtained by minimizing the total
path length which is the sum of lengths of shortest paths between
every pair of all nodes.
Abstract: A statistical optimization of the saccharification
process of EFB was studied. The statistical analysis was done by
applying faced centered central composite design (FCCCD) under
response surface methodology (RSM). In this investigation, EFB
dose, enzyme dose and saccharification period was examined, and the
maximum 53.45% (w/w) yield of reducing sugar was found with 4%
(w/v) of EFB, 10% (v/v) of enzyme after 120 hours of incubation. It
can be calculated that the conversion rate of cellulose content of the
substrate is more than 75% (w/w) which can be considered as a
remarkable achievement. All the variables, linear, quadratic and
interaction coefficient, were found to be highly significant, other than
two coefficients, one quadratic and another interaction coefficient.
The coefficient of determination (R2) is 0.9898 that confirms a
satisfactory data and indicated that approximately 98.98% of the
variability in the dependent variable, saccharification of EFB, could
be explained by this model.
Abstract: In this paper, a delayed competitive system with the effect of toxic substances is investigated. With the aid of differential equations with piecewise constant arguments, a discrete analogue of continuous non-autonomous delayed competitive system with the effect of toxic substances is proposed. By using Gaines and Mawhin,s continuation theorem of coincidence degree theory, a easily verifiable sufficient condition for the existence of positive solutions of difference equations is obtained.
Abstract: This paper presents an algorithm based on the
wavelet decomposition, for feature extraction from the ECG signal
and recognition of three types of Ventricular Arrhythmias using
neural networks. A set of Discrete Wavelet Transform (DWT)
coefficients, which contain the maximum information about the
arrhythmias, is selected from the wavelet decomposition. After that a
novel clustering algorithm based on nature inspired algorithm (Ant
Colony Optimization) is developed for classifying arrhythmia types.
The algorithm is applied on the ECG registrations from the MIT-BIH
arrhythmia and malignant ventricular arrhythmia databases. We
applied Daubechies 4 wavelet in our algorithm. The wavelet
decomposition enabled us to perform the task efficiently and
produced reliable results.
Abstract: Behavior of dams against the seismic loads has been
studied by many researchers. Most of them proposed new numerical
methods to investigate the dam safety. In this paper, to study the
effect of nonlinear parameters of concrete in gravity dams, a twodimensional
approach was used including the finite element method,
staggered method and smeared crack approach. Effective parameters
in the models are physical properties of concrete such as modulus of
elasticity, tensile strength and specific fracture energy. Two different
models were used in foundation (mass-less and massed) in order to
determine the seismic response of concrete gravity dams. Results
show that when the nonlinear analysis includes the dam- foundation
interaction, the foundation-s mass, flexibility and radiation damping
are important in gravity dam-s response.
Abstract: Integrins are a large family of multidomain α/β cell
signaling receptors. Some integrins contain an additional inserted I
domain, whose earliest expression appears to be with the chordates,
since they are observed in the urochordates Ciona intestinalis (vase
tunicate) and Halocynthia roretzi (sea pineapple), but not in integrins
of earlier diverging species. The domain-s presence is viewed as a
hallmark of integrins of higher metazoans, however in vertebrates,
there are clearly three structurally-different classes: integrins without
I domains, and two groups of integrins with I domains but separable
by the presence or absence of an additional αC helix. For example,
the αI domains in collagen-binding integrins from Osteichthyes
(bony fish) and all higher vertebrates contain the specific αC helix,
whereas the αI domains in non-collagen binding integrins from
vertebrates and the αI domains from earlier diverging urochordate
integrins, i.e. tunicates, do not. Unfortunately, within the early
chordates, there is an evolutionary gap due to extinctions between the
tunicates and cartilaginous fish. This, coupled with a knowledge gap
due to the lack of complete genomic data from surviving species,
means that the origin of collagen-binding αC-containing αI domains
remains unknown. Here, we analyzed two available genomes from
Callorhinchus milii (ghost shark/elephant shark; Chondrichthyes –
cartilaginous fish) and Petromyzon marinus (sea lamprey;
Agnathostomata), and several available Expression Sequence Tags
from two Chondrichthyes species: Raja erinacea (little skate) and
Squalus acanthias (dogfish shark); and Eptatretus burgeri (inshore
hagfish; Agnathostomata), which evolutionary reside between the
urochordates and osteichthyes. In P. marinus, we observed several
fragments coding for the αC-containing αI domain, allowing us to
shed more light on the evolution of the collagen-binding integrins.
Abstract: This paper presents a case study that uses processoriented
simulation to identify bottlenecks in the service delivery
system in an emergency department of a hospital in the United Arab
Emirates. Using results of the simulation, response surface models
were developed to explain patient waiting time and the total time
patients spend in the hospital system. Results of the study could be
used as a service improvement tool to help hospital management in
improving patient throughput and service quality in the hospital
system.
Abstract: The increase popularity of multimedia application especially in image processing places a great demand on efficient data storage and transmission techniques. Network communication such as wireless network can easily be intercepted and cause of confidential information leaked. Unfortunately, conventional compression and encryption methods are too slow; it is impossible to carry out real time secure image processing. In this research, Embedded Zerotree Wavelet (EZW) encoder which specially designs for wavelet compression is examined. With this algorithm, three methods are proposed to reduce the processing time, space and security protection that will be secured enough to protect the data.