Abstract: This paper presents design, analysis and comparison of the different rotor type permanent magnet machines. The presented machines are designed as having same geometrical dimensions and same materials for comparison. The main machine parameters of interior and exterior rotor type machines including eddy current effect, torque-speed characteristics and magnetic analysis are investigated using MAXWELL program. With this program, the components of the permanent magnet machines can be calculated with high accuracy. Six types of Permanent machines are compared with respect to their topology, size, magnetic field, air gap flux, voltage, torque, loss and efficiency. The analysis results demonstrate the effectiveness of the proposed machines design methodology. We believe that, this study will be a helpful resource in terms of examination and comparison of the basic structure and magnetic features of the PM (Permanent magnet) machines which have different rotor structure.
Abstract: In this study, the effect of mechanical activation on the synthesis of Fe3Al/Al2O3 nanocomposite has been investigated by using mechanochemical method. For this purpose, Aluminum powder and hematite as precursors, with stoichiometric ratio, have been utilized and other effective parameters in milling process were kept constant. Phase formation analysis, crystallite size measurement and lattice strain were studied by X-ray diffraction (XRD) by using Williamson-Hall method as well as microstructure and morphology were explored by Scanning electron microscopy (SEM). Also, Energy-dispersive X-ray spectroscopy (EDX) analysis was used in order to probe the particle distribution. The results showed that after 30-hour milling, the reaction was started, combustibly done and completed.
Abstract: Calcite aCalcite and aragonite are the two common
polymorphs of CaCO3 observed as biominerals. It is universal that
the sea water contents a high Mg2+ (50mM) relative to Ca2+ (10mM).
In vivo crystallization, Mg2+ inhibits calcite formation. For this
reason, stony corals skeleton may be formed only aragonite crystals
in the biocalcification. It is special in case of soft corals of which
formed only calcite crystal; however, this interesting phenomenon,
still uncharacterized in the marine environment, has been explored in
this study using newly purified cell-free proteins isolated from the
endoskeletal sclerites of soft coral. By recording the decline of pH in
vitro, the control of CaCO3 nucleation and crystal growth by the cellfree
proteins was revealed. Using Atomic Force Microscope, here we
find that these endoskeletal cell-free proteins significantly design the
morphological shape in the molecular-scale kinetics of crystal
formation and those proteins act as surfactants to promote ion
attachment at calcite steps.nd aragonite are the two common polymorphs of CaCO3 observed as biominerals. It is universal that the sea water contents a high Mg2+ (50mM) relative to Ca2+ (10mM). In vivo crystallization, Mg2+ inhibits calcite formation. For this reason, stony corals skeleton may be formed only aragonite crystals in the biocalcification. It is special in case of soft corals of which formed only calcite crystal; however, this interesting phenomenon, still uncharacterized in the marine environment, has been explored in this study using newly purified cell-free proteins isolated from the endoskeletal sclerites of soft coral. By recording the decline of pH in vitro, the control of CaCO3 nucleation and crystal growth by the cell-free proteins was revealed. Using Atomic Force Microscope, here we find that these endoskeletal cell-free proteins significantly design the morphological shape in the molecular-scale kinetics of crystal formation and those proteins act as surfactants to promote ion attachment at calcite steps. KeywordsBiomineralization, Calcite, Cell-free protein, Soft coral
Abstract: In this paper, the existence of periodic solutions of a delayed competitive system with the effect of toxic substances is investigated by using the Gaines and Mawhin,s continuation theorem of coincidence degree theory on time scales. New sufficient conditions are obtained for the existence of periodic solutions. The approach is unified to provide the existence of the desired solutions for the continuous differential equations and discrete difference equations. Moreover, The approach has been widely applied to study existence of periodic solutions in differential equations and difference equations.
Abstract: Water level forecasting using records of past time series is of importance in water resources engineering and management. For example, water level affects groundwater tables in low-lying coastal areas, as well as hydrological regimes of some coastal rivers. Then, a reliable prediction of sea-level variations is required in coastal engineering and hydrologic studies. During the past two decades, the approaches based on the Genetic Programming (GP) and Artificial Neural Networks (ANN) were developed. In the present study, the GP is used to forecast daily water level variations for a set of time intervals using observed water levels. The measurements from a single tide gauge at Urmia Lake, Northwest Iran, were used to train and validate the GP approach for the period from January 1997 to July 2008. Statistics, the root mean square error and correlation coefficient, are used to verify model by comparing with a corresponding outputs from Artificial Neural Network model. The results show that both these artificial intelligence methodologies are satisfactory and can be considered as alternatives to the conventional harmonic analysis.
Abstract: In this article, the flow behavior around a NACA 0012 airfoil which is oscillating with different Reynolds numbers and in various amplitudes has been investigated numerically. Numerical simulations have been performed with ANSYS software. First, the 2- D geometry has been studied in different Reynolds numbers and angles of attack with various numerical methods in its static condition. This analysis was to choose the best turbulent model and comparing the grids to have the optimum one for dynamic simulations. Because the analysis was to study the blades of wind turbines, the Reynolds numbers were not arbitrary. They were in the range of 9.71e5 to 22.65e5. The angle of attack was in the range of -41.81° to 41.81°. By choosing the forward wind speed as the independent parameter, the others like Reynolds and the amplitude of the oscillation would be known automatically. The results show that the SST turbulent model is the best choice that leads the least numerical error with respect the experimental ones. Also, a dynamic stall phenomenon is more probable at lower wind speeds in which the lift force is less.
Abstract: the data of Taiwanese 8th grader in the 4th cycle of
Trends in International Mathematics and Science Study (TIMSS) are
analyzed to examine the influence of the science teachers- preference
in experimental teaching on the relationships between the affective
variables ( the perceived usefulness of science, ease of using science
and science learning interest) and the academic achievement in science.
After dealing with the missing data, 3711 students and 145 science
teacher-s data were analyzed through a Hierarchical Linear Modeling
technique. The major objective of this study was to determine the role
of the experimental teaching moderates the relationship between
perceived usefulness and achievement.
Abstract: The structural interpretation of a part of eastern Potwar
(Missa Keswal) has been carried out with available seismological,
seismic and well data. Seismological data contains both the source
parameters and fault plane solution (FPS) parameters and seismic data
contains ten seismic lines that were re-interpreted by using well data.
Structural interpretation depicts two broad types of fault sets namely,
thrust and back thrust faults. These faults together give rise to pop up
structures in the study area and also responsible for many structural
traps and seismicity. Seismic interpretation includes time and depth
contour maps of Chorgali Formation while seismological interpretation
includes focal mechanism solution (FMS), depth, frequency,
magnitude bar graphs and renewal of Seismotectonic map. The Focal
Mechanism Solutions (FMS) that surrounds the study area are
correlated with the different geological and structural maps of the area
for the determination of the nature of subsurface faults. Results of
structural interpretation from both seismic and seismological data
show good correlation. It is hoped that the present work will help in
better understanding of the variations in the subsurface structure and
can be a useful tool for earthquake prediction, planning of oil field and
reservoir monitoring.
Abstract: In this paper, we study the pulsatile flow of blood through stenotic arteries. The inner layer of arterial walls is modeled as a porous medium and human blood is assumed as an incompressible fluid. A numerical algorithm based on the finite element method is developed to simulate the blood flow through both the lumen region and the porous wall. The algorithm is then applied to study the flow behaviour and to investigate the significance of the non-Newtonian effect.
Abstract: Bioprocesses are appreciated as difficult to control because their dynamic behavior is highly nonlinear and time varying, in particular, when they are operating in fed batch mode. The research objective of this study was to develop an appropriate control method for a complex bioprocess and to implement it on a laboratory plant. Hence, an intelligent control structure has been designed in order to produce biomass and to maximize the specific growth rate.
Abstract: Deep Brain Stimulation or DBS is a surgical treatment for Parkinson-s Disease with three stimulation parameters: frequency, pulse width, and voltage. The parameters should be selected appropriately to achieve effective treatment. This selection now, performs clinically. The aim of this research is to study chaotic behavior of recorded tremor of patients under DBS in order to present a computational method to recognize stimulation optimum voltage. We obtained some chaotic features of tremor signal, and discovered embedding space of it has an attractor, and its largest Lyapunov exponent is positive, which show tremor signal has chaotic behavior, also we found out, in optimal voltage, entropy and embedding space variance of tremor signal have minimum values in comparison with other voltages. These differences can help neurologists recognize optimal voltage numerically, which leads to reduce patients' role and discomfort in optimizing stimulation parameters and to do treatment with high accuracy.
Abstract: A SCADA (Supervisory Control And Data
Acquisition) system is an industrial control and monitoring system for
national infrastructures. The SCADA systems were used in a closed
environment without considering about security functionality in the
past. As communication technology develops, they try to connect the
SCADA systems to an open network. Therefore, the security of the
SCADA systems has been an issue. The study of key management for
SCADA system also has been performed. However, existing key
management schemes for SCADA system such as SKE(Key
establishment for SCADA systems) and SKMA(Key management
scheme for SCADA systems) cannot support broadcasting
communication. To solve this problem, an Advanced Key
Management Architecture for Secure SCADA Communication has
been proposed by Choi et al.. Choi et al.-s scheme also has a problem
that it requires lots of computational cost for multicasting
communication. In this paper, we propose an enhanced scheme which
improving computational cost for multicasting communication with
considering the number of keys to be stored in a low power
communication device (RTU).
Abstract: In this study, an analysis has been performed for
conjugate heat and mass transfer of a steady laminar boundary-layer
mixed convection of magnetic hydrodynamic (MHD) flow with
radiation effect of second grade subject to suction past a stretching
sheet. Parameters E Nr, Gr, Gc, Ec and Sc represent the dominance of
the viscoelastic fluid heat and mass transfer effect which have
presented in governing equations, respectively. The similar
transformation and the finite-difference method have been used to
analyze the present problem. The conjugate heat and mass transfer
results show that the non-Newtonian viscoelastic fluid has a better heat
transfer effect than the Newtonian fluid. The free convection with a
larger r G or c G has a good heat transfer effect better than a smaller
r G or c G , and the radiative convection has a good heat transfer
effect better than non-radiative convection.
Abstract: The purpose of this paper is to examine the financing
practices of SMEs in Libya in two different phases of business life
cycle: start-up and matured stages. Moreover, SMEs- accessing bank
loan issues is also identified. The study was conducted by taking into
account the aspect of demand. The findings are based on a sample of
76 SMEs in Libya through the adoption of questionnaires. The results
have pinpointed several things- evidently, SMEs use informal
financing sources which prefer personal savings; SME owners are
willing to apply for bank loan, that the most pressing problem has
been identified, not to apply bank loan is loan with interest (religion
factor).
Abstract: Although electrical motors are still the main devices
used in vehicular exhaust comprises more than 95 percent of the air
pollution in Taiwan's largest city, Taipei. On average, all commuters in Taipei travel 13.6 km daily, while motorcycle commuters travel 12.2 km. The convenience and mobility of motorcycles makes them
irreplaceable in Taiwan city traffic but they add significantly to air pollution problems. In order to improve air pollution conditions, some
new types of vehicles have been proposed, such as fuel cell driven and
hybrid energy vehicles. In this study, we develop a model pneumatic hybrid motorcycle system and simulate its acceleration and mileage
(km/L) performance. The results show that the pneumatic hybrid
motorcycle can improve efficiency.
Abstract: Exposure to ambient air pollution has been linked to a
number of health outcomes, starting from modest transient changes in
the respiratory tract and impaired pulmonary function, continuing to
restrict activity/reduce performance and to the increase emergency
rooms visits, hospital admissions or mortality. The increase of
allergenic symptoms has been associated with air contaminants such
as ozone, particulate matter, fungal spores and pollen.
Considering the potential relevance of crossed effects of nonbiological
pollutants and airborne pollens and fungal spores on
allergy worsening, the aim of this work was to evaluate the influence
of non-biological pollutants (O3 and PM10) and meteorological
parameters on the concentrations of pollen and fungal spores using
multiple linear regressions.
The data considered in this study were collected in Oporto which
is the second largest Portuguese city, located in the North. Daily
mean of O3, PM10, pollen and fungal spore concentrations,
temperature, relative humidity, precipitation, wind velocity, pollen
and fungal spore concentrations, for 2003, 2004 and 2005 were
considered. Results showed that the 90th percentile of the adjusted
coefficient of determination, P90 (R2aj), of the multiple regressions
varied from 0.613 to 0.916 for pollen and from 0.275 to 0.512 for
fungal spores. O3 and PM10 showed to have some influence on the
biological pollutants. Among the meteorological parameters
analysed, temperature was the one that most influenced the pollen
and fungal spores airborne concentrations. Relative humidity also
showed to have some influence on the fungal spore dispersion.
Nevertheless, the models for each pollen and fungal spore were
different depending on the analysed period, which means that the
correlations identified as statistically significant can not be, even so,
consistent enough.
Abstract: We compare three categorical data clustering
algorithms with respect to the problem of classifying cultural data
related to the aesthetic judgment of comics artists. Such a
classification is very important in Comics Art theory since the
determination of any classes of similarities in such kind of data will
provide to art-historians very fruitful information of Comics Art-s
evolution. To establish this, we use a categorical data set and we
study it by employing three categorical data clustering algorithms.
The performances of these algorithms are compared each other,
while interpretations of the clustering results are also given.
Abstract: This research was to study on background and social
and cultural context of Kamchanoad community for sustainable
tourism management. All data was collected through in-depth
interview with village headmen, community committees, teacher,
monks, Kamchanoad forest field officers and respected senior citizen
above 60 years old in the community who have lived there for more
than 40 years. Altogether there were 30 participants for this research.
After analyzing the data, content from interview and discussion,
Kamchanoad has both high land and low land in the region as well as
swamps that are very capable of freshwater animals’ conservation.
Kamchanoad is also good for agriculture and animal farming. 80% of
Kamchanoad’s land are forest, freshwater and rice farms.
Kamchanoad was officially set up as community in 1994 as “Baan
Nonmuang”. Inhabitants in Kamchanoad make a living by farming
based on sufficiency economy. They have rice farm, eucalyptus farm,
cassava farm and rubber tree farm. Local people in Kamchanoad still
believe in the myth of Srisutto Naga. They are still religious and love
to preserve their traditional way of life. In order to understand how to
create successful tourism business in Kamchanoad, we have to study
closely on local culture and traditions. Outstanding event in
Kamchanoad is the worship of Grand Srisutto, which is on the fullmoon
day of 6th month or Visakhabucha Day. Other big events are
also celebration at the end of Buddhist lent, Naga firework, New
Year celebration, Boon Mahachart, Songkran, Buddhist Lent, Boon
Katin and Loy Kratong. Buddhism is the main religion in
Kamchanoad. The promotion of tourism in Kamchanoad is expected
to help spreading more income for this region. More infrastructures
will be provided for local people as well as funding for youth support
and people activities.
Abstract: This study is concerned with pH solution detection
using 2 × 4 flexible sensor array based on a plastic polyethylene
terephthalate (PET) substrate that is coated a conductive layer and a
ruthenium dioxide (RuO2) sensitive membrane with the technologies
of screen-printing and RF sputtering. For data analysis, we also
prepared a dynamic measurement system for acquiring the response
voltage and analyzing the characteristics of the working electrodes
(WEs), such as sensitivity and linearity. In this condition, an array
measurement system was designed to acquire the original signal from
sensor array, and it is based on the method of digital signal processing
(DSP). The DSP modifies the unstable acquisition data to a direct
current (DC) output using the technique of digital filter. Hence, this
sensor array can obtain a satisfactory yield, 62.5%, through the design
measurement and analysis system in our laboratory.
Abstract: Statistics Canada stated that the wastewater treatment
facilities in most provinces are aging and passes 63% of their useful
life in 2007 the highest ratio among public infrastructure assets.
Currently, there is no standard condition rating system for wastewater
treatment plants that give a specific rating index that describe the
physical integrity of different infrastructure elements in the treatment
plant and its environmental performance. The main objective of this
study is to develop a condition-rating index for wastewater treatment
plants mainly activated sludge systems. The proposed WWTP CRI, is
based on dividing the treatment plant into its three treatment phases;
primary phase, secondary phase and the tertiary phase. The
condition-rating index will reflect the infrastructures state for each
phase, mainly tanks, pipes, blowers and pumps.