Abstract: High Voltage Direct Current (HVDC) power
transmission is employed to move large amounts of electric power.
There are several possibilities to enhance the transient stability in a
power system. One adequate option is by using the high
controllability of the HVDC if HVDC is available in the system. This
paper presents a control technique for HVDC to enhance the transient
stability. The strategy controls the power through the HVDC to help
make the system more transient stable during disturbances. Loss of
synchronism is prevented by quickly producing sufficient
decelerating energy to counteract accelerating energy gained during.
In this study, the power flow in the HVDC link is modulated with the
addition of an auxiliary signal to the current reference of the rectifier
firing angle controller. This modulation control signal is derived from
speed deviation signal of the generator utilizing a PD controller; the
utilization of a PD controller is suitable because it has the property of
fast response. The effectiveness of the proposed controller is
demonstrated with a SMIB test system.
Abstract: Optic disk segmentation plays a key role in the mass
screening of individuals with diabetic retinopathy and glaucoma
ailments. An efficient hardware-based algorithm for optic disk
localization and segmentation would aid for developing an automated
retinal image analysis system for real time applications. Herein,
TMS320C6416DSK DSP board pixel intensity based fractal analysis
algorithm for an automatic localization and segmentation of the optic
disk is reported. The experiment has been performed on color and
fluorescent angiography retinal fundus images. Initially, the images
were pre-processed to reduce the noise and enhance the quality. The
retinal vascular tree of the image was then extracted using canny
edge detection technique. Finally, a pixel intensity based fractal
analysis is performed to segment the optic disk by tracing the origin
of the vascular tree. The proposed method is examined on three
publicly available data sets of the retinal image and also with the data
set obtained from an eye clinic. The average accuracy achieved is
96.2%. To the best of the knowledge, this is the first work reporting
the use of TMS320C6416DSK DSP board and pixel intensity based
fractal analysis algorithm for an automatic localization and
segmentation of the optic disk. This will pave the way for developing
devices for detection of retinal diseases in the future.
Abstract: This paper directs attention to the limitations of the
teacher-centered strategy in teaching. The aim of this study is to draw
more educational attention to learner-centered strategy in order to
shift the emphasis from the traditional concept of teaching to a new
concept in teaching. To begin bridging the traditional concept of
teaching and the new concept, the study will explore the new concept
of teaching to support teaching in Arab World generally and in Iraq
specifically. A qualitative case study orientation was used to collect
data in the form of classroom observations, interviews and field
notes. The teaching practices used by three university instructors are
investigated and according to the findings, some explanations and
recommendations are made.
Abstract: The present study aimed to investigate the effect of
synchronous music in Gymnastics' motor skill performance among
undergraduate female students in physical education college at Basra
University. The researcher used experimental design. 20 female
students of physical education divided equally into two groups, (10)
experimental group with music, (10) control group without music.
All participants complete 6 weeks in testing. Data analysis based on
T-test shows significant difference at (α = 0.05) in all skills level
between experimental and control groups in favor of experimental
group. Results of this study contribute to developing the role of
synchronous music in improving gymnastic skills performance.
Abstract: Background: The change in foot posture can possibly
generate changes in the pelvic alignment. There is still a lack of
evidence about the effects of bilateral and unilateral flatfoot on
possible changes in pelvic alignment. The purpose of this study was
to investigate the effect of flatfoot on the sagittal and frontal planes of
pelvic postures. Materials and Methods: 56 subjects, aged 18–40
years, were assigned into three groups: 20 healthy subjects, 19
subjects with bilateral flexible second-degree flat foot, and 17
subjects with unilateral flexible second-degree flat foot. 3D
assessment of the pelvis using the formetric-II device was used to
evaluate pelvic alignment in the frontal and sagittal planes by
measuring pelvic inclination and pelvic tilt angles. Results: ANOVA
test with LSD test were used for statistical analysis. Both Unilateral
and bilateral second degree flatfoot produced significant (P
Abstract: In this paper, we present a four-step ortho-rectification
procedure for real-time geo-referencing of video data from a low-cost
UAV equipped with a multi-sensor system. The basic procedures for
the real-time ortho-rectification are: (1) decompilation of the video
stream into individual frames; (2) establishing the interior camera
orientation parameters; (3) determining the relative orientation
parameters for each video frame with respect to each other; (4)
finding the absolute orientation parameters, using a self-calibration
bundle and adjustment with the aid of a mathematical model. Each
ortho-rectified video frame is then mosaicked together to produce a
mosaic image of the test area, which is then merged with a well
referenced existing digital map for the purpose of geo-referencing
and aerial surveillance. A test field located in Abuja, Nigeria was
used to evaluate our method. Video and telemetry data were collected
for about fifteen minutes, and they were processed using the four-step
ortho-rectification procedure. The results demonstrated that the
geometric measurement of the control field from ortho-images is
more accurate when compared with those from original perspective
images when used to pin point the exact location of targets on the
video imagery acquired by the UAV. The 2-D planimetric accuracy
when compared with the 6 control points measured by a GPS receiver
is between 3 to 5 metres.
Abstract: In this study, the signal of brain electrical activities of
the sixteen students selected from the Department of Electrical and
Energy at Usak University have been recorded during a lecturer
performed happiness emotions for the first group and anger emotions
for the second group in different time while the groups were in the
classroom separately. The attention and meditation data extracted
from the recorded signals have been analyzed and evaluated toward
the teacher’s specific emotion states simultaneously. Attention levels
of students who are under influence of happiness emotions of the
lecturer have a positive trend and attention levels of students who are
under influence of anger emotions of the lecturer have a negative
trend. The meditation or mental relaxation levels of students who are
under influence of happiness emotions of the lecturer are 34.3%
higher comparing with the mental relaxation levels of students who
are under influence of anger emotions of the lecturer.
Abstract: This study examined whether big five personality traits
affect game addiction with control of psychological, social, and
demographic factors. Specifically, using data from a survey of 789
game users in Korea, we conducted a regression analysis to see the
associations of psychological (loneliness/depression), social (activities
with family/friends), self-efficacy (game/general), gaming (daily
gaming time/perception), demographic (age/gender), and personality
traits (extraversion, neuroticism conscientiousness, agreeableness, &
openness) with the degree of game addiction. Results showed that
neuroticism increase game addiction with no effect of extraversion on
the addiction. General self-efficacy negatively affected game
addiction, whereas game self-efficacy increased the degree of game
addiction. Loneliness enhanced game addiction while depression
showed a negative effect on the addiction. Results and implications are
discussed.
Abstract: In present global scenario, aluminum alloys are
coining the attention of many innovators as competing structural
materials for automotive and space applications. Comparing to other
challenging alloys, especially, 7xxx series aluminum alloys have
been studied seriously because of benefits such as moderate strength;
better deforming characteristics and affordable cost. It is expected
that substitution of aluminum alloys for steels will result in great
improvements in energy economy, durability and recyclability.
However, it is necessary to improve the strength and the formability
levels at low temperatures in aluminum alloys for still better
applications. Aluminum–Zinc–Magnesium with or without other
wetting agent denoted as 7XXX series alloys are medium strength
heat treatable alloys. In addition to Zn, Mg as major alloying
additions, Cu, Mn and Si are the other solute elements which
contribute for the improvement in mechanical properties by suitable
heat treatment process. Subjecting to suitable treatments like age
hardening or cold deformation assisted heat treatments; known as low
temperature thermomechanical treatments (LTMT) the challenging
properties might be incorporated. T6 is the age hardening or
precipitation hardening process with artificial aging cycle whereas T8
comprises of LTMT treatment aged artificially with X% cold
deformation. When the cold deformation is provided after solution
treatment, there is increase in hardness related properties such as
wear resistance, yield and ultimate strength, toughness with the
expense of ductility. During precipitation hardening both hardness
and strength of the samples are increasing. The hardness value may
further improve when room temperature deformation is positively
supported with age hardening known as thermomechanical treatment.
It is intended to perform heat treatment and evaluate hardness, tensile
strength, wear resistance and distribution pattern of reinforcement in
the matrix. 2 to 2.5 and 3 to 3.5 times increase in hardness is reported
in age hardening and LTMT treatments respectively as compared to
as-cast composite. There was better distribution of reinforcements in
the matrix, nearly two fold increase in strength levels and up to 5
times increase in wear resistance are also observed in the present
study.
Abstract: In Electric Power Steering (EPS), spoke type
Brushless AC (BLAC) motors offer distinct advantages over other
electric motor types in terms torque smoothness, reliability and
efficiency. This paper deals with the shape optimization of spoke
type BLAC motor, in order to reduce cogging torque. This paper
examines 3 steps skewing rotor angle, optimizing rotor core edge and
rotor overlap length for reducing cogging torque in spoke type BLAC
motor. The methods were applied to existing machine designs and
their performance was calculated using finite- element analysis
(FEA). Prototypes of the machine designs were constructed and
experimental results obtained. It is shown that the FEA predicted the
cogging torque to be nearly reduce using those methods.
Abstract: Cyber exercises used to assess the preparedness of a
community against cyber crises, technology failures and Critical
Information Infrastructure (CII) incidents. The cyber exercises also
called cyber crisis exercise or cyber drill, involved partnerships or
collaboration of public and private agencies from several sectors.
This study investigates Organisation Cyber Resilience (OCR) of
participation sectors in cyber exercise called X Maya in Malaysia.
This study used a principal based cyber resilience survey called CSuite
Executive checklist developed by World Economic Forum in
2012. To ensure suitability of the survey to investigate the OCR, the
reliability test was conducted on C-Suite Executive checklist items.
The research further investigates the differences of OCR in ten
Critical National Infrastructure Information (CNII) sectors
participated in the cyber exercise. The One Way ANOVA test result
showed a statistically significant difference of OCR among ten CNII
sectors participated in the cyber exercise.
Abstract: Numerical studies have been carried out using a
validated two-dimensional standard k-omega turbulence model for
the design optimization of a thrust vector control system using shock
induced self-impinging supersonic secondary double jet. Parametric
analytical studies have been carried out at different secondary
injection locations to identifying the highest unsymmetrical
distribution of the main gas flow due to shock waves, which produces
a desirable side force more lucratively for vectoring. The results from
the parametric studies of the case on hand reveal that the shock
induced self-impinging supersonic secondary double jet is more
efficient in certain locations at the divergent region of a CD nozzle
than a case with supersonic single jet with same mass flow rate. We
observed that the best axial location of the self-impinging supersonic
secondary double jet nozzle with a given jet interaction angle, built-in
to a CD nozzle having area ratio 1.797, is 0.991 times the primary
nozzle throat diameter from the throat location. We also observed
that the flexible steering is possible after invoking ON/OFF facility to
the secondary nozzles for meeting the onboard mission requirements.
Through our case studies we concluded that the supersonic self-impinging
secondary double jet at predesigned jet interaction angle
and location can provide more flexible steering options facilitating
with 8.81% higher thrust vectoring efficiency than the conventional
supersonic single secondary jet without compromising the payload
capability of any supersonic aerospace vehicle.
Abstract: In recent research copper and manganese systems
were found to be the most active in CO and organic compounds
oxidation among the base catalysts. The mixed copper manganese
oxide has been widely studied in oxidation reactions because of their
higher activity at low temperatures in comparison with single oxide
catalysts. The results showed that the formation of spinel
CuxMn3−xO4 in the oxidized catalyst is responsible for the activity
even at room temperature. That is why the most of the investigations
are focused on the hopcalite catalyst (CuMn2O4) as the best coppermanganese
catalyst. Now it’s known that this is true only for CO
oxidation, but not for mixture of CO and VOCs. The purpose of this
study is to investigate the alumina supported copper-manganese
catalysts with different Cu/Mn molar ratio in terms of oxidation of
CO, methanol and dimethyl ether. The catalysts were prepared by impregnation of γ-Al2O3 with
copper and manganese nitrates and the catalytic activity
measurements were carried out in two stage continuous flow
equipment with an adiabatic reactor for simultaneous oxidation of all
compounds under the conditions closest possible to the industrial. Gas
mixtures on the input and output of the reactor were analyzed with a
gas chromatograph, equipped with FID and TCD detectors. The
texture characteristics were determined by low-temperature (- 196oС)
nitrogen adsorption in a Quantachrome Instruments NOVA 1200e
(USA) specific surface area & pore analyzer. Thermal, XRD and
TPR analyses were performed. It was established that the active component of the mixed Cu-
Mn/γ–alumina catalysts strongly depends on the Cu/Mn molar ratio.
Highly active alumina supported Cu-Mn catalysts for CO, methanol
and DME oxidation were synthesized. While the hopcalite is the best
catalyst for CO oxidation, the best compromise for simultaneous
oxidation of all components is the catalyst with Cu/Mn molar ratio
1:5.
Abstract: In this paper air quality conditions in Makkah and
Leeds are compared. These two cities have totally different climatic
conditions. Makkah climate is characterised as hot and dry (arid)
whereas that of Leeds is characterised as cold and wet (temperate).
This study uses air quality data from 2012 collected in Makkah,
Saudi Arabia and Leeds, UK. The concentrations of all pollutants,
except NO are higher in Makkah. Most notable, the concentrations of
PM10 are much higher in Makkah than in Leeds. This is probably due
to the arid nature of climatic conditions in Makkah and not solely due
to anthropogenic emission sources, otherwise like PM10 some of the
other pollutants, such as CO, NO, and SO2 would have shown much
greater difference between Leeds and Makkah. Correlation analysis is
performed between different pollutants at the same site and the same
pollutants at different sites. In Leeds the correlation between PM10
and other pollutants is significantly stronger than in Makkah. Weaker
correlation in Makkah is probably due to the fact that in Makkah
most of the gaseous pollutants are emitted by combustion processes,
whereas most of the PM10 is generated by other sources, such as
windblown dust, re-suspension, and construction activities. This is in
contrast to Leeds where all pollutants including PM10 are
predominantly emitted by combustions, such as road traffic.
Furthermore, in Leeds frequent rains wash out most of the
atmospheric particulate matter and suppress re-suspension of dust.
Temporal trends of various pollutants are compared and discussed.
This study emphasises the role of climatic conditions in managing air
quality, and hence the need for region-specific controlling strategies
according to the local climatic and meteorological conditions.
Abstract: Studying stress and strain trends in the femur and
recognizing femur failure mechanism is very important for
preventing hip fracture in the elderly. The aim of this study was to
identify high stress and strain regions in the femur during normal
walking and falling to find the mechanical behavior and failure
mechanism of the femur. We developed a finite element model of the
femur from the subject’s quantitative computed tomography (QCT)
image and used it to identify potentially high stress and strain regions
during the single-leg stance and the sideways fall. It was found that
fracture may initiate from the superior region of femoral neck and
propagate to the inferior region during a high impact force such as
sideways fall. The results of this study showed that the femur bone is
more sensitive to strain than stress which indicates the effect of
strain, in addition to effect of stress, should be considered for failure
analysis.
Abstract: Present work deals with the possible use of fertigation
in agriculture and its impact on the availability of mineral nitrogen
(Nmin) in topsoil and subsoil horizons. The aim of the present study is
to demonstrate the effect of the organic matter presence in fertigation
on microbial transformation and availability of mineral nitrogen
forms. The main investigation reason is the potential use of pretreated
waste water, as a source of organic carbon (Corg) and residual
nutrients (Nmin) for fertigation. Laboratory experiment has been
conducted to demonstrate the effect of the arable land fertilization
method on the Nmin availability in different depths of the soil with
the usage of model experimental containers filled with soil from
topsoil and podsoil horizons that were taken from the precise area.
Tufted hairgrass (Deschampsia caespitosa) has been chosen as a
model plant. The water source protection zone Brezova nad Svitavou
has been a research area where significant underground reservoirs of
drinking water of the highest quality are located. From the second
half of the last century local sources of drinking water show
nitrogenous compounds increase that get here almost only from
arable lands. Therefore, an attention of the following text focuses on
the fate of mineral nitrogen in the complex plant-soil. Research
results show that the fertigation application with Corg in a
combination with mineral fertilizer can reduce the amount of Nmin
leached from topsoil horizon of agricultural soils. In addition, some
plants biomass production reduces may occur.
Abstract: In recent decades, particulate matter (PM10) have
received much attention due to its potential adverse health impact and
the subsequent need to better control or regulate these pollutants.
The aim of this paper is focused on study risk assessment of PM10
in four different districts (Shebikah, Masfalah, Aziziyah, Awali) in
Makkah, Saudi Arabia during the period from 1 Ramadan 1434 AH -
27 Safar 1435 AH. Samples were collected by using Low Volume
Sampler (LVS Low Volume Sampler) device and filtration method
for estimating the total concentration of PM10.
The study indicated that the mean PM10 concentrations were 254.6
(186.1 - 343.2) μg/m3 in Shebikah, 184.9 (145.6 - 271.4) μg/m3 in
Masfalah, 162.4 (92.4-253.8) μg/m3 in Aziziyah, and 56.0 (44.5 -
119.8) μg/m3 in Awali. These values did not exceed the permissible
limits in PME (340 μg/m3 as daily average). Furthermore, health
assessment is carried out using AirQ2.2.3 model to estimate the
number of hospital admissions due to respiratory diseases. The
cumulative number of cases per 100,000 were 1534 (18-3050 case),
which lower than that recorded in the United States, Malaysia. The
concentration response coefficient was 0.49 (95% CI 0.05 - 0.70) per
10 μg/m3 increase of PM10.
Abstract: Traditionally, the embodied energy of design choices
which reduce operational energy were assumed to have a negligible
impact on the life cycle energy of buildings. However with new
buildings having considerably lower operational energy, the
significance of embodied energy increases. A life cycle assessment of
a population of house designs was conducted in a mild and mixed
climate zone. It was determined not only that embodied energy
dominates life cycle energy, but that the impact on embodied of
design choices was of equal significance to the impact on operational
energy.
Abstract: Zn alloy and composite coatings are widely used in
buildings and structures, automobile and fasteners industries to
protect steel component from corrosion. In this paper, Zn-Ni-Al2O3
nanocomposite coatings were electrodeposited on mild steel using a
novel sol enhanced electroplating method. In this method, transparent
Al2O3 sol was added into the acidic Zn-Ni bath to produced Zn-Ni-
Al2O3 nanocomposite coatings. The effect of alumina sol on the
electrodeposition process, and coating properties was investigated
using cyclic voltammetry, XRD, ESEM and Tafel test. Results from
XRD tests showed that the structure of all coatings was single γ-
Ni5Zn21 phase. Cyclic voltammetry results showed that the
electrodeposition overpotential was lower in the presence of alumina
sol in the bath, and caused the reduction potential of Zn-Ni to shift to
more positive values. Zn-Ni-Al2O3 nanocomposite coatings produced
more uniform and compact deposits, with fine grained microstructure
when compared to Zn-Ni coatings. The corrosion resistance of Zn-Ni
coatings was improved significantly by incorporation of alumina
nanoparticles into the coatings.
Abstract: Sodium formate is the chemical substance used for
food additive. Catalase is the important antioxidative enzyme in
protecting the cell from oxidative damage by reactive oxygen species
(ROS). The resultant level of oxidative stress in sodium formatetreated
lymphocytes was investigated. The sodium formate
concentrations of 0.05, 0.1, 0.2, 0.4 and 0.6 mg/mL were treated in
human lymphocytes for 12 hours. After 12 treated hours, catalase
activity change was measured in sodium formate-treated
lymphocytes. The results showed that the sodium formate
concentrations of 0.4 and 0.6 mg/mL significantly decreased catalase
activities in lymphocytes (P < 0.05). The change of catalase activity
in sodium formate-treated lymphocytes may be the oxidative damage
marker for detect sodium formate exposure in human.