Abstract: The pursuit of the MPPT has led to the development of many kinds of controllers, one of which is the Fuzzy Logic controller, which has proven its worth. To further tune this controller this paper will discuss and analyze the use of Genetic Algorithms to tune the Fuzzy Logic Controller. It will provide an introduction to both systems, and test their compatibility and performance.
Abstract: We propose a code acquisition scheme called improved
multiple-shift (IMS) for optical code division multiple access
systems, where the optical orthogonal code is used instead of the
pseudo noise code. Although the IMS algorithm has a similar process
to that of the conventional MS algorithm, it has a better code
acquisition performance than the conventional MS algorithm. We
analyze the code acquisition performance of the IMS algorithm and
compare the code acquisition performances of the MS and the IMS
algorithms in single-user and multi-user environments.
Abstract: Zinc oxide (ZnO) is one of the light emitting materials in ultraviolet (UV) region. In addition, ZnO nanostructures are also attracting increasing research interest as buildingblocks for UV optoelectronic applications. We have succeeded in synthesizing vertically-aligned ZnO nanostructures by laser interference patterning, which is catalyst-free and non-contact technique. In this study, vertically-aligned ZnO nanowall arrays were synthesized using two-beam interference. The maximum height and average thickness of the ZnO nanowalls were about 4.5µm and 200 nm, respectively.UV lasing from a piece of the ZnO nanowall was obtained under the third harmonic of a Q-switched Nd:YAG laser excitation, and the estimated threshold power density for lasing was about 150 kW/cm2. Furthermore, UV lasing from the vertically-aligned ZnO nanowall was also achieved. The results indicate that ZnO nanowalls can be applied to random laser.
Abstract: Unmanned aircraft systems (UAS) are playing
increasingly prominent roles in defense programs and defense
strategies around the world. Technology advancements have
enabled the development of it to do many excellent jobs as
reconnaissance, surveillance, battle fighters, and communications
relays. Simulating a small unmanned aerial vehicle (SUAV)
dynamics and analyzing its behavior at the preflight stage is too
important and more efficient. The first step in the UAV design is
the mathematical modeling of the nonlinear equations of motion. .
In this paper, a survey with a standard method to obtain the full
non-linear equations of motion is utilized, and then the
linearization of the equations according to a steady state flight
condition (trimming) is derived. This modeling technique is
applied to an Ultrastick-25e fixed wing UAV to obtain the valued
linear longitudinal and lateral models. At the end the model is
checked by matching between the behavior of the states of the nonlinear
UAV and the resulted linear model with doublet at the
control surfaces.
Abstract: The impact of Special Economic Zones (SEZs) has
been analyzed for many years by researchers. There are lot of
theoretical studies proving the SEZs importance for regional
development, however, there is lack of empirical studies (and they
are mainly focused on China market) that are based on available data.
The theoretical studies indicate the various impacts of enterprises
operating within SEZs on the economy. The article proves that, in
case of Poland, locating SEZs in municipalities is an important part
of increasing municipalities’ income. Therefore SEZs have a positive
impact on regional development. Municipality income is understood
as taxes paid by taxpayers who depend on SEZ companies’
performance. The analysis includes the Corporate Income Tax (CIT),
Personal Income Tax (PIT) and real estate tax. The effects of SEZs
on regional development were narrowed to a few variables that are
most significant for the financial system. The analysis indicates the
significant impact of SEZs on the amount of taxes influencing the
municipality budget.
Abstract: This paper presents the results and findings from a
parametric study on the water surface elevation at upstream of bridge
constriction for subcritical flow. In this study, the influence of
Manning's Roughness Coefficient of main channel (nmc) and
floodplain (nfp), and bridge opening (b) flow rate (Q), contraction
(kcon) and expansion coefficients (kexp) were investigated on
backwater level. The DECK bridge models with different span widths
and without any pier were investigated within the two stage channel
having various roughness conditions. One of the most commonly
used commercial one-dimensional HEC-RAS model was used in this
parametric study. This study showed that the effects of main channel
roughness (nmc) and flow rate (Q) on the backwater level are much
higher than those of the floodplain roughness (nfp). Bridge opening
(b) with contraction (kcon) and expansion coefficients (kexp) have very
little effect on the backwater level within this range of parameters.
Abstract: Future mobile networks following 5th generation will
be characterized by one thousand times higher gains in capacity;
connections for at least one hundred billion devices; user experience
capable of extremely low latency and response times. To be close to
the capacity requirements and higher reliability, advanced
technologies have been studied, such as multiple connectivity, small
cell enhancement, heterogeneous networking, and advanced
interference and mobility management. This paper is focused on the
multiple connectivity in heterogeneous cellular networks. We
investigate the performance of coverage and user throughput in several
deployment scenarios. Using the stochastic geometry approach, the
SINR distributions and the coverage probabilities are derived in case
of dual connection. Also, to compare the user throughput enhancement
among the deployment scenarios, we calculate the spectral efficiency
and discuss our results.
Abstract: IEEE 802.11a/b/g standards provide multiple
transmission rates, which can be changed dynamically according to the
channel condition. Cooperative communications were introduced to
improve the overall performance of wireless LANs with the help of
relay nodes with higher transmission rates. The cooperative
communications are based on the fact that the transmission is much
faster when sending data packets to a destination node through a relay
node with higher transmission rate, rather than sending data directly to
the destination node at low transmission rate. To apply the cooperative
communications in wireless LAN, several MAC protocols have been
proposed. Some of them can result in collisions among relay nodes in a
dense network. In order to solve this problem, we propose a new
protocol. Relay nodes are grouped based on their transmission rates.
And then, relay nodes only in the highest group try to get channel
access. Performance evaluation is conducted using simulation, and
shows that the proposed protocol significantly outperforms the
previous protocol in terms of throughput and collision probability.
Abstract: The aim of this study is to analyze the role and
effectiveness of internal mechanism (audit committee) of corporate
governance on credit institutions performance in Croatia. Based on
research objective, sample of 78 credit institutions listed on Zagreb
Stock Exchange, from 2007 to 2012, has been collected and
efficiency index of audit committee (EIAC) has been created. Based
on the sample and created EIAC, conclusions are as follows: audit
committees of credit institutions have medium efficiency, based on
EIAC measurement; there is a significant difference in audit
committee effectiveness, in observed period; there is no positive
relationship between audit committee effectiveness and credit
institution performance; there is a significant difference between
level of audit committee effectiveness and audit firm type. Future
research should contain increased number of elements in EIAC
creation and increased sample, for all obligators who need to
establish audit committee.
Abstract: A nanocrystalline thin film of ZnSe was successfully
electrodeposited on copper substrate using a non-aqueous solution
and subsequently annealed in air at 400°C. XRD analysis indicates
the polycrystalline deposit of (111) plane in both the cases. The
sharpness of the peak increases due to annealing of the film and
average grain size increases to 20 nm to 27nm. SEM photograph
indicate that grains are uniform and densely distributed over the
surface. Annealing increases the average grain size by 20%. The EDS
spectroscopy shows the ratio of Zn & Se is 1.1 in case of annealed
film. AFM analysis indicates the average roughness of the film
reduces from 181nm to 165nm due to annealing of the film. The
bandgap also decreases from 2.71eV to 2.62eV.
Abstract: The main objective of aircraft aerodynamics is to
enhance the aerodynamic characteristics and maneuverability of the
aircraft. This enhancement includes the reduction in drag and stall
phenomenon. The airfoil which contains dimples will have
comparatively less drag than the plain airfoil. Introducing dimples on
the aircraft wing will create turbulence by creating vortices which
delays the boundary layer separation resulting in decrease of pressure
drag and also increase in the angle of stall. In addition, wake
reduction leads to reduction in acoustic emission. The overall
objective of this paper is to improve the aircraft maneuverability by
delaying the flow separation point at stall and thereby reducing the
drag by applying the dimple effect over the aircraft wing. This project
includes both computational and experimental analysis of dimple
effect on aircraft wing, using NACA 0018 airfoil. Dimple shapes of
Semi-sphere, hexagon, cylinder, square are selected for the analysis;
airfoil is tested under the inlet velocity of 30m/s and 60m/s at
different angle of attack (5˚, 10˚, 15˚, 20˚, and 25˚). This analysis
favors the dimple effect by increasing L/D ratio and thereby
providing the maximum aerodynamic efficiency, which provides the
enhanced performance for the aircraft.
Abstract: Moodle is an open source learning management
system that enables creation of a powerful and flexible learning
environment. Many organizations, especially learning institutions
have customized Moodle open source LMS for their own use. In
general open source LMSs are of great interest due to many
advantages they offer in terms of cost, usage and freedom to
customize to fit a particular context. Tanzania Secondary School e-
Learning (TanSSe-L) system is the learning management system for
Tanzania secondary schools. TanSSe-L system was developed using
a number of methods, one of them being customization of Moodle
Open Source LMS. This paper presents few areas on the way Moodle
OS LMS was customized to produce a functional TanSSe-L system
fitted to the requirements and specifications of Tanzania secondary
schools’ context.
Abstract: This paper outlines the basic installation and operation of magnetic inductive flow velocity sensors on large underground cooling water pipelines. Research on the effects of cathodic protection as well as into other factors that might influence the overall performance of the meter is presented in this paper. The experiments were carried out on an immersion type magnetic meter specially used for flow measurement of cooling water pipeline. An attempt has been made in this paper to outline guidelines that can ensure accurate measurement related to immersion type magnetic meters on underground pipelines.
Abstract: Potato (Solanum tuberosum L.) is one of the major
vegetable crops that are grown world –wide because of its economic
importance. This experiment investigated the effect of local sands
(River Base, Al-Ekader and Karbala) on number and total weight of
minitubers. Statistical analysis revealed that there were no significant
differences among sand cultures in number of stem/plant, chlorophyll
index and tubers dry weight. River Base sand had the highest plant
height (74.9 cm), leaf number/plant number (39.3), leaf area (84.4
dcm2⁄plant), dry weight/plant (26.31), tubers number/plant (8.5),
tubers weight/plant (635.53 gm) and potato tuber yields/trove (28.60
kg), whereas the Karbala sand had lower performance. All the
characters had positive and significant correlation with yields except
the traits number of stem and tuber dry weight.
Abstract: While millings materials from old pavement surface
can be an important component of cost effective maintenance
operation, their use in maintenance projects are not uniform and well
documented. This study documents the different maintenance
practices followed by four transportation districts of New Mexico
Department of Transportation (NMDOT) in an attempt to find
whether millings are being used in maintenance projects by those
districts. Based on existing literature, a questionnaire was developed
related to six common maintenance practices. NMDOT district
personal were interviewed face to face to discuss and get answers to
that questionnaire. It revealed that NMDOT districts mainly use chip
seal and patching. Other maintenance procedures such as sand seal,
scrub seal, slurry seal, and thin overlay have limited use. Two out of
four participating districts do not have any documents on chip
sealing; rather they employ the experiences of the chip seal crew. All
districts use polymer modified high float emulsion (HFE100P) for
chip seal with an application rate ranging from 0.4 to 0.56 gallons per
square yard. Chip application rate varies from 15 to 40 lb/ square
yard. State wide, the thickness of chip seal varies from 3/8'' to 1'' and
life varies from 3 to 10 years. NMDOT districts mainly use three type
of patching: pothole, dig-out and blade patch. Pothole patches are
used for small potholes and during emergency, dig-out patches are
used for all type of potholes sometimes after pothole patching, and
blade patch is used when a significant portion of the pavement is
damaged. Pothole patches last as low as three days whereas, blade
patch lasts as long as 3 years. It was observed that all participating
districts use millings in maintenance projects.
Abstract: The rhizome of Java grass, Cyperus rotundus was
extracted different organic polar and non-polar solvents and
performed the in vitro antiviral and immunostimulant activities
against White Spot Syndrome Virus (WSSV) and Vibrio harveyi
respectively. Based on the initial screening the ethyl acetate extract of
C. rotundus was strong activities and further it was purified through
silica column chromatography and the fractions were screened again
for antiviral and immunostimulant activity. Among the different
fractions screened against the WSSV and V. harveyi, the fractions, FIII
to FV had strong activities. In order to study the in vivo influence
of C. rotundus, the fractions (F-III to FV) were pooled and delivered
to the F. indicus through artificial feed for 30 days. After the feeding
trail the experimental and control diet fed F. indicus were challenged
with virulent WSSV and studied the survival, molecular diagnosis,
biochemical, haematological, and immunological parameters.
Surprisingly, the pooled fractions (F-IV to FVI) incorporated diets
helped to significantly (P
Abstract: For a bluff body, dimples behave like roughness
elements in stimulating a turbulent boundary layer, leading to delayed
flow separation, a smaller wake and lower form drag. This is very
different in principle from the application of dimples to streamlined
body, where any reduction in drag would be predominantly due to a
reduction in skin friction. In the present work, a car model with
different dimple geometry is simulated using k-ε turbulence modeling
to determine its effect to the aerodynamics performance. Overall, the
results show that the application of dimples manages to reduce the
drag coefficient of the car model.
Abstract: This work introduces a simple device designed to
perform in-situ direct shear and sinkage tests on granular materials
as sand, clays, or regolith. It consists of a box nested within a larger
box. Both have open bottoms, allowing them to be lowered into the
material. Afterwards, two rotating plates on opposite sides of the
outer box will rotate outwards in order to clear regolith on either
side, providing room for the inner box to move relative to the plates
and perform a shear test without the resistance of the surrounding
soil. From this test, Coulomb parameters, including cohesion and
internal friction angle, as well as, Bekker parameters can be inferred.
This device has been designed for a laboratory setting, but with few
modifications, could be put on the underside of a rover for use in
a remote location. The goal behind this work is to ultimately create
a compact, but accurate measuring tool to put onto a rover or any
kind of exploratory vehicle to test for regolith properties of celestial
bodies.
Abstract: This paper proposes a rotational invariant texture
feature based on the roughness property of the image for psoriasis
image analysis. In this work, we have applied this feature for image
classification and segmentation. The fuzzy concept is employed to
overcome the imprecision of roughness. Since the psoriasis lesion is
modeled by a rough surface, the feature is extended for calculating
the Psoriasis Area Severity Index value. For classification and
segmentation, the Nearest Neighbor algorithm is applied. We have
obtained promising results for identifying affected lesions by using
the roughness index and severity level estimation.
Abstract: Ti6Al4V alloy is highly used in the automotive and
aerospace industry due to its good machining characteristics. Micro
EDM drilling is commonly used to drill micro hole on extremely hard
material with very high depth to diameter ratio. In this study, the
parameters of micro-electrical discharge machining (EDM) in drilling
of Ti6Al4V alloy is optimized for higher machining accuracy with
less hole-dilation and hole taper ratio. The micro-EDM machining
parameters includes, peak current and pulse on time. Fuzzy analysis
was developed to evaluate the machining accuracy. The analysis
shows that hole-dilation and hole-taper ratio are increased with the
increasing of peak current and pulse on time. However, the surface
quality deteriorates as the peak current and pulse on time increase.
The combination that gives the optimum result for hole dilation is
medium peak current and short pulse on time. Meanwhile, the
optimum result for hole taper ratio is low peak current and short pulse
on time.