Abstract: A design problem of non-uniform circular antenna arrays for maximum reduction of both the side lobe level (SLL) and first null beam width (FNBW) is dealt with. This problem is modeled as a simple optimization problem. The method of Firefly algorithm (FFA) is used to determine an optimal set of current excitation weights and antenna inter-element separations that provide radiation pattern with maximum SLL reduction and much improvement on FNBW as well. Circular array antenna laid on x-y plane is assumed. FFA is applied on circular arrays of 8-, 10-, and 12- elements. Various simulation results are presented and hence performances of side lobe and FNBW are analyzed. Experimental results show considerable reductions of both the SLL and FNBW with respect to those of the uniform case and some standard algorithms GA, PSO and SA applied to the same problem.
Abstract: This paper describes optimal thinning of an Elliptical
Cylindrical Array (ECA) of uniformly excited isotropic antennas
which can generate directive beam with minimum relative Side Lobe
Level (SLL). The Particle Swarm Optimization (PSO) method, which
represents a new approach for optimization problems in
electromagnetic, is used in the optimization process. The PSO is used
to determine the optimal set of ‘ON-OFF’ elements that provides a
radiation pattern with maximum SLL reduction. Optimization is done
without prefixing the value of First Null Beam Width (FNBW). The
variation of SLL with element spacing of thinned array is also
reported. Simulation results show that the number of array elements
can be reduced by more than 50% of the total number of elements in
the array with a simultaneous reduction in SLL to less than -27dB.
Abstract: Bone hydatidosis is an infection in worldwide distribution. Although there is no evidence in literature on Bone Hydatid disease in Libya, we tried to present the first Epidemiological study of this disease in Eastern Libya through retrospective study from 1995 to 2013. Our data were collected from 3 hospitals in Eastern Libya particularly the sheep-raising areas with total number of musculoskeletal infection cases of two thousand one hundred ninety four (2,194). There were five (5) five cases of bone infection, four (4) of it have been diagnosed after more than three (3) months. Our study is comparable to other international study but this type of bone infection need further studies for effective control strategies for all dogs to avoid serious complications that might happened from the delay in diagnosing this type of disease.
Abstract: In Line start permanent magnet synchronous motor, eccentricity is a common fault that can make it necessary to remove the motor from the production line. However, because the motor may be inaccessible, diagnosing the fault is not easy. This paper presents an FEM that identifies different models, static eccentricity, dynamic eccentricity, and mixed eccentricity, at no load and full load. The method overcomes the difficulty of applying FEMs to transient behavior. It simulates motor speed, torque and flux density distribution along the air gap for SE,DE, and ME. This paper represents the various effects of different eccentricitiestypes on the transient performance.
Abstract: Recently, the interest of globalization in the field of
teacher education has increased. In the U.S., the government is trying
to enhance the quality of education through a global approach in
education. To do so, the schools in the U.S. are recruiting teachers with
global capability from countries like Korea where competent teachers
are being trained. Meanwhile, in the case of Korea, although excellent
teachers have been cultivated every year, due to a low birth rate it is
not easy to become a domestic teacher. To solve the trouble that the
two countries are facing, the study first examines the demand and
necessity of globalization in the field of teacher education between
Korea and the U.S. Second, we propose a new project, called the
‘Global Teachers University (GTU)’ program to satisfy the demands
of both countries. Finally, we provide its implications to build the
future educational cooperation for teacher training in a global context.
Abstract: This paper proposes a single relay selection scheme in
cooperative communication. Decode-and-forward scheme is
considered when a source node wants to cooperate with a single relay
for data transmission. To use the proposed single relay selection
scheme, the source node makes a little different pattern signal which is
not complex pattern and broadcasts it. The proposed scheme does not
require the channel state information between the source node and
candidates of the relay during the relay selection. Therefore, it is able
to be used in many fields.
Abstract: In broadcasting and cellular system, a cooperative
scheme is proposed for the improvement of performance of bit error
rate. Up to date, the coverage of broadcasting system coexists with the
coverage of cellular system. Therefore each user in a cellular coverage
is frequently involved in a broadcasting coverage. The proposed
cooperative scheme is derived from the shared areas. The users receive
signals from both broadcasting station and cellular station. The
proposed scheme selects a cellular base station of a worse channel to
achieve better performance of bit error rate in cooperation. The
performance of the proposed scheme is evaluated in fading channel.
Abstract: Compatibility between sulfonated acetone- formalehyde superplasticizer (SAF) and copolymer-based grinding aids (GA) were studied by fluidity, Zeta potential, setting time of cement pasts, initial slump and slump flow of concrete and compressive strength of concrete. ESEM, MIP, and XRD were used to investigate the changing of microstructure of interior concrete. The results indicated that GA could noticeably enhance the dispersion ability of SAF. It was found that better fluidity and slump-keeping ability of cement paste were obtained in the case of GA. In addition, GA together with SAF had a certain retardation effect on hydration of cement paste. With increasing of the GA dosage, the dispersion ability and retardation effect of admixture increased. The compressive strength of the sample made with SAF and GA after 28 days was higher than that of the control sample made only with SAF. The initial slump and slump flow of concrete increased by 10.0% and 22.9%, respectively, while 0.09 wt.% GA was used. XRD examination indicated that new products were not found in the case of GA. In addition, more dense arrangement of hydrates and lower porosity of the specimen were observed by ESEM and MIP, which contributed to higher compressive strength.
Abstract: Reconfigurable antennas represent a recent innovation in antenna design that changes from classical fixed-form, fixed function antennas to modifiable structures that can be adapted to fit the requirements of a time varying system.
The ability to control the operating band of an antenna system can have many useful applications. Systems that operate in an acquire-and-track configuration would see a benefit from active bandwidth control. In such systems a wide band search mode is first employed to find a desired signal then a narrow band track mode is used to follow only that signal. Utilizing active antenna bandwidth control, a single antenna would function for both the wide band and narrow band configurations providing the rejection of unwanted signals with the antenna hardware. This ability to move a portion of the RF filtering out of the receiver and onto the antenna itself will also aid in reducing the complexity of the often expensive RF processing subsystems.
Abstract: This paper proposes a way of removing noises and reducing the number of colors contained in a JPEG image. Main purpose of this project is to convert color images to monochrome images for the color-blind. We treat the crispy color images like the Tokyo subway map. Each color in the image has an important information. But for the color blinds, similar colors cannot be distinguished. If we can convert those colors to different gray values, they can distinguish them. Therefore we try to convert color images to monochrome images.
Abstract: An experimental study was conducted to investigate the effect of hooked-end steel fibers on the flexural behavior of normal and high strength concrete matrices. The fibers content appropriate for the concrete matrices investigated was also determined based on flexural tests on standard prisms. Parameters investigated include: matrix compressive strength ranging from 45 MPa to 70 MPa, corresponding to normal and high strength concrete matrices respectively; fibers volume fraction including 0, 0.5%, 0.76% and 1%, equivalent to 0, 40, 60, and 80 kg/m3 of hooked-end steel fibers respectively. Test results indicated that flexural strength and toughness of normal and high strength concrete matrices were significantly improved with the increase in the fibers content added; whereas a slight improvement in compressive strength was observed for the same matrices. Furthermore, the test results indicated that the effect of increasing the fibers content was more pronounced on increasing the flexural strength of high strength concrete than that of normal concrete.
Abstract: In this research, the capability of neural networks in
modeling and learning complicated and nonlinear relations has been
used to develop a model for the prediction of changes in the diameter
of bubbles in pool boiling distilled water. The input parameters used
in the development of this network include element temperature, heat
flux, and retention time of bubbles. The test data obtained from the
experiment of the pool boiling of distilled water, and the
measurement of the bubbles form on the cylindrical element. The
model was developed based on training algorithm, which is
typologically of back-propagation type. Considering the correlation
coefficient obtained from this model is 0.9633. This shows that this
model can be trusted for the simulation and modeling of the size of
bubble and thermal transfer of boiling.
Abstract: In this research, the changes in bubbles diameter and
number that may occur due to the change in heat flux of pure water
during pool boiling process. For this purpose, test equipment was
designed and developed to collect test data. The bubbles were graded
using Caliper Screen software. To calculate the growth and
nucleation rates of bubbles under different fluxes, population balance
model was employed. The results show that the increase in heat flux
from q=20 kw/m2 to q= 102 kw/m2 raised the growth and nucleation
rates of bubbles.
Abstract: Cubic equations of state like Redlich–Kwong (RK)
EOS have been proved to be very reliable tools in the prediction of
phase behavior. Despite their good performance in compositional
calculations, they usually suffer from weaknesses in the predictions
of saturated liquid density. In this research, RK equation was
modified. The result of this study show that modified equation has
good agreement with experimental data.
Abstract: In this study, two kinds of nondestructive evaluation
(NDE) techniques (rebound hardness and ultrasonic pulse velocity
methods) are investigated for the effective maintenance of underwater
concrete structures. A new methodology to estimate the underwater
concrete strengths more effectively, named “artificial neural network
(ANN) – based concrete strength estimation with the combination of
rebound hardness and ultrasonic pulse velocity methods” is proposed
and verified throughout a series of experimental works.
Abstract: Service quality is the highest requirement by users,
especially for the service in electronic government. During the past
decades, it has become a major area of academic investigation.
Considering this issue, there are a lot of researches that evaluated the
dimensions and e-service contexts. This study also identified the
dimensions of service quality, but focuses on a new concept and
provides a new methodology in developing measurement scales of
e-service quality such as information quality, service quality and
organization quality. Finally, this study will suggest a key factor to
evaluate e-government service quality better.
Abstract: The efficiency of heavy metals removal from sewage
sludge in bioleaching processes with heterotrophic, chemoautotrophic
(sulphur-oxidizing) sludge cenoses and chemical leaching (in
distilled water, weakly acidic or alkaline medium) was compared.
The efficacy of heavy metals removal from sewage sludge varies
from 83 % (Zn) up to 14 % (Cr) and follows the order: Zn > Mn > Cu
> Ni > Co > Pb > Cr. The advantages of metals bioleaching process
at heterotrophic metabolism were shown. A new process for
bioconversation of sewage sludge into fertilizer at middle
temperatures after partial heavy metals removal was developed. This
process is based on enhancing vital ability of heterotrophic
microorganisms by adding easily metabolized nutrients and synthesis
of metabolites by growing sludge cenoses. These metabolites possess
the properties of heavy metals extractants and flocculants which
provide the enhancement of sludge flocks sedimentation. The process
results in biomineral fertilizer of prolonged action with immobilized
sludge bioelements. The fertilizer satisfies the EU limits for the
sewage sludge of agricultural utilization. High efficiency of the
biomineral fertilizer obtained has been demonstrated in vegetation
experiments.
Abstract: A two-dimensional linear wave-body interaction problem can be solved using a desingularized integral method by placing free surface Rankine sources over calm water surface and satisfying boundary conditions at prescribed collocation points on the
calm water surface. A new free-surface Rankine source distribution scheme, determined by the intersection points of free surface and body surface, is developed to reduce numerical computation cost. Associated with this, a new treatment is given to the intersection point. The present scheme results are in good agreement with traditional numerical results and measurements.
Abstract: In this research, the TRACE/PARCS model of
Lungmen ABWR has been developed for verification of ultimate
response guideline (URG) efficiency. This ultimate measure was
named as DIVing plan, abbreviated from system depressurization,
water injection and containment venting. The simulation initial
condition is 100% rated power/100% rated core flow. This research
focuses on the estimation of the time when the fuel might be damaged
with no water injection by using TRACE/PARCS first. Then, the
effect of the reactor core isolation system (RCIC), control
depressurization and ac-independent water addition system (ACIWA),
which can provide the injection with 950 gpm are also estimated for
the station blackout (SBO) transient.
Abstract: Fuel rod analysis program transient (FRAPTRAN)
code was used to study the fuel rod performance during a postulated
large break loss of coolant accident (LBLOCA) in Maanshan nuclear
power plant (NPP). Previous transient results from thermal hydraulic
code, TRACE, with the same LBLOCA scenario, were used as input
boundary conditions for FRAPTRAN. The simulation results showed
that the peak cladding temperatures and the fuel centerline
temperatures were all below the 10CFR50.46 LOCA criteria. In
addition, the maximum hoop stress was 18 MPa and the oxide
thickness was 0.003mm for the present simulation cases, which are all
within the safety operation ranges. The present study confirms that this
analysis method, the FRAPTRAN code combined with TRACE, is an
appropriate approach to predict the fuel integrity under LBLOCA with
operational ECCS.