Abstract: This study numerically investigates the effects of Electrohydrodynamic on flow patterns and heat transfer enhancement within a cavity which is on the lower wall of channel. In this simulation, effects of using ground wire and ground plate on the flow patterns are compared. Moreover, the positions of electrode wire respecting with ground are tested in the range of angles θ = 0 - 180o. High electrical voltage exposes to air is 20 kV. Bulk mean velocity and temperature of inlet air are controlled at 0.1 m/s and 60 OC, respectively. The result shows when electric field is applied, swirling flow is appeared in the channel. In addition, swirling flow patterns in the main flow of using ground plate are widely spreader than that of using ground wire. Moreover, direction of swirling flow also affects the flow pattern and heat transfer in a cavity. These cause the using ground wire to give the maximum temperature and heat transfer higher than using ground plate. Furthermore, when the angle is at θ = 60o, high shear flow effect is obtained. This results show high strength of swirling flow and effective heat transfer enhancement.
Abstract: Image mosaicing is a technique that permits to enlarge the field of view of a camera. For instance, it is employed to achieve panoramas with common cameras or even in scientific applications, to achieve the image of a whole culture in microscopical imaging. Usually, a mosaic of cell cultures is achieved through using automated microscopes. However, this is often performed in batch, through CPU intensive minimization algorithms. In addition, live stem cells are studied in phase contrast, showing a low contrast that cannot be improved further. We present a method to study the flat field from live stem cells images even in case of 100% confluence, this permitting to build accurate mosaics on-line using high performance algorithms.
Abstract: This study compares family communication patterns in association with family socio-cultural status, especially marriage and family pattern, and couples- socio-economic status between Muslim and Santal communities in rural Bangladesh. A total of 288 couples, 145 couples from the Muslim and 143 couples from the Santal were randomly selected through cluster sampling procedure from Kalna village situated in Tanore Upazila of Rajshahi district of Bangladesh, where both the communities dwell as neighbors. In order to collect data from the selected samples, interview method with semistructural questionnaire schedule was applied. The responses given by the respondents were analyzed by Pearson-s chi-squire test and bivariate correlation techniques. The results of Pearson-s chi-squire test revealed that family communication patterns (X2= 25. 90, df= 2, p0.05) were significantly different between the Muslim and Santal communities. In addition, Spearman-s bivariate correlation coefficients suggested that among the exogenous factors, family type (rs=.135, p
Abstract: Microstrip antennas are conformable to planar and
nonplanar surfaces, simple and inexpensive to fabricate using modern
printed-circuit technology. Circular polarization of low-profile
microstrip patch with high bandwidth is achieved in this research
through the use of a three-cross-arms branch-line coupler with
sequential rotated arrays, another low-profile antenna of hollow
cylinder is also proposed and the function of reconnaissance with
microstrip antenna on Mini UAV (unmanned aerial vehicle) are
evaluated in practical flight test.
Abstract: Technical laboratories are typically considered as
highly hazardous places in the polytechnic institution when
addressing the problems of high incidences and fatality rates. In
conjunction with several topics covered in the technical curricular,
safety and health precaution should be highlighted in order to
connect to few key ideas of being safe. Therefore the assessment of
safety awareness in terms of safety and health about hazardous and
risks at laboratories is needed and has to be incorporated with
technical education and other training programmes. The purpose of
this study was to determine the efficacy of technical laboratory safety
in one of the polytechnics in northern region. The study examined
three related issues that were; the availability of safety material and
equipment, safety practice adopted by technical teachers and
administrator-s safety attitudes in enforcing safety to the students. A
model of efficacy technical laboratory was developed to test the
linear relationship between existing safety material and equipment,
teachers- safety practice and administrators- attitude in enforcing
safety and to identify which of technical laboratory safety issues was
the most pertinent factor to realize safety in technical laboratory.
This was done by analyzing survey-based data sets particularly those
obtained from samples of 210 students in the polytechnic. The
Pearson Correlation was used to measure the association between the
variables and to test the research hypotheses. The result of the study
has found that there was a significant correlation between existing
safety material and equipment, safety practice adopted by teacher
and administrator-s attitude. There was also a significant relationship
between technical laboratory safety and safety practice adopted by
teacher and between technical laboratory safety and administrator
attitude. Hence, safety practice adopted by teacher and administrator
attitude is vital in realizing technical laboratory safety.
Abstract: In this paper, many techniques for blind identification of moving average (MA) process are presented. These methods utilize third- and fourth-order cumulants of the noisy observations of the system output. The system is driven by an independent and identically distributed (i.i.d) non-Gaussian sequence that is not observed. Two nonlinear optimization algorithms, namely the Gradient Descent and the Gauss-Newton algorithms are exposed. An algorithm based on the joint-diagonalization of the fourth-order cumulant matrices (FOSI) is also considered, as well as an improved version of the classical C(q, 0, k) algorithm based on the choice of the Best 1-D Slice of fourth-order cumulants. To illustrate the effectiveness of our methods, various simulation examples are presented.
Abstract: Thousands of masters athletes participate
quadrennially in the World Masters Games (WMG), yet this cohort
of athletes remains proportionately under-investigated. Due to a
growing global obesity pandemic in context of benefits of physical
activity across the lifespan, the BMI trends for this unique population
was of particular interest. The nexus between health, physical
activity and aging is complex and has raised much interest in recent
times due to the realization that a multifaceted approach is necessary
in order to counteract the obesity pandemic. By investigating age
based trends within a population adhering to competitive sport at
older ages, further insight might be gleaned to assist in understanding
one of many factors influencing this relationship.BMI was derived
using data gathered on a total of 6,071 masters athletes (51.9% male,
48.1% female) aged 25 to 91 years ( =51.5, s =±9.7), competing at
the Sydney World Masters Games (2009). Using linear and loess
regression it was demonstrated that the usual tendency for prevalence
of higher BMI increasing with age was reversed in the sample. This
trend in reversal was repeated for both male and female only sub-sets
of the sample participants, indicating the possibility of improved
prevalence of BMI with increasing age for both the sample as a
whole and these individual sub-groups.This evidence of improved
classification in one index of health (reduced BMI) for masters
athletes (when compared to the general population) implies there are
either improved levels of this index of health with aging due to
adherence to sport or possibly the reduced BMI is advantageous and
contributes to this cohort adhering (or being attracted) to masters
sport at older ages.
Abstract: Mobile Ad Hoc network is an infrastructure less
network which operates with the coordination of each node. Each node
believes to help another node, by forwarding its data to/from another
node. Unlike a wired network, nodes in an ad hoc network are resource
(i.e. battery, bandwidth computational capability and so on)
constrained. Such dependability of one node to another and limited
resources of nodes can result in non cooperation by any node to
accumulate its resources. Such non cooperation is known as selfish
behavior.
This paper discusses the performance analysis of very well known
MANET single-path (i.e. AODV) and multi-path (i.e. AOMDV)
routing protocol, in the presence of selfish behaviors. Along with
existing selfish behaviors, a new variation is also studied. Extensive
simulations were carried out using ns-2 and the study concluded that
the multi-path protocol (i.e. AOMDV) with link disjoint configuration
outperforms the other two configurations.
Abstract: Wireless capsule Endoscopy (WCE) has rapidly
shown its wide applications in medical domain last ten years
thanks to its noninvasiveness for patients and support for thorough
inspection through a patient-s entire digestive system including
small intestine. However, one of the main barriers to efficient
clinical inspection procedure is that it requires large amount of
effort for clinicians to inspect huge data collected during the
examination, i.e., over 55,000 frames in video. In this paper, we
propose a method to compute meaningful motion changes of
WCE by analyzing the obtained video frames based on regional
optical flow estimations. The computed motion vectors are used to
remove duplicate video frames caused by WCE-s imaging nature,
such as repetitive forward-backward motions from peristaltic
movements. The motion vectors are derived by calculating
directional component vectors in four local regions. Our
experiments are performed on small intestine area, which is of
main interest to clinical experts when using WCEs, and our
experimental results show significant frame reductions comparing
with a simple frame-to-frame similarity-based image reduction
method.
Abstract: This paper is concerned with the existence of a linear copositive Lyapunov function(LCLF) for a special class of switched positive linear systems(SPLSs) composed of continuousand discrete-time subsystems. Firstly, by using system matrices, we construct a special kind of matrices in appropriate manner. Secondly, our results reveal that the Hurwitz stability of these matrices is equivalent to the existence of a common LCLF for arbitrary finite sets composed of continuous- and discrete-time positive linear timeinvariant( LTI) systems. Finally, a simple example is provided to illustrate the implication of our results.
Abstract: This paper tries to study the effect of geosynthetic inclusion on the improvement of the load-settlement characters of two layered soil. In addition, the effect of geogrid and geotextile in reduction of the required thickness of subbase layer in unpaved roads is studied. Considering the vast application of bearing ratio tests in road construction projects, this test is used in present investigation. Bearing ratio tests were performed on two layered soil including a granular soil layer at the top (as the subbase layer) and a weak clayey soil placed at the bottom (as the subgrade layer). These tests were performed for different conditions including unreinforced and reinforced by geogrid and geotextile and three thicknesses for top layer soil (subbase layer). In the reinforced condition the reinforcing element was placed on the interface of the top granular layer and the beneath clayey layer to study the separation effect of geosynthetics. In all tests the soils (both granular and clayey soil layers) were compacted according to optimum water content. At the end, the diagrams were plotted and were compared with each other. Furthermore, a comparison between geogrids and geotextiles behaviors on two layer soil is done in this paper. The results show an increase in compression strength of reinforced specimen in comparison with unreinforced soil sample. The effect of geosynthetic inclusion reduces by increasing the subbase thickness. In addition it was found that geogrids have more desirable behavior rather than geotextiles due to interlocking with the subbase layer aggregates.
Abstract: Some of the students' problems in writing skill stem
from inadequate preparation for the writing assignment. Students
should be taught how to write well when they arrive in language
classes. Having selected a topic, the students examine and explore the
theme from as large a variety of viewpoints as their background and
imagination make possible. Another strategy is that the students
prepare an Outline before writing the paper. The comparison between
the two mentioned thought provoking techniques was carried out
between the two class groups –students of Islamic Azad University of
Dezful who were studying “Writing 2" as their main course. Each
class group was assigned to write five compositions separately in
different periods of time. Then a t-test for each pair of exams between
the two class groups showed that the t-observed in each pair was
more than the t-critical. Consequently, the first hypothesis which
states those who utilize Brainstorming as a thought provoking
technique in prewriting phase are more successful than those who
outline the papers before writing was verified.
Abstract: When acid is pumped into damaged reservoirs for
damage removal/stimulation, distorted inflow of acid into the
formation occurs caused by acid preferentially traveling into highly
permeable regions over low permeable regions, or (in general) into
the path of least resistance. This can lead to poor zonal coverage and
hence warrants diversion to carry out an effective placement of acid.
Diversion is desirably a reversible technique of temporarily reducing
the permeability of high perm zones, thereby forcing the acid into
lower perm zones.
The uniqueness of each reservoir can pose several challenges to
engineers attempting to devise optimum and effective diversion
strategies. Diversion techniques include mechanical placement and/or
chemical diversion of treatment fluids, further sub-classified into ball
sealers, bridge plugs, packers, particulate diverters, viscous gels,
crosslinked gels, relative permeability modifiers (RPMs), foams,
and/or the use of placement techniques, such as coiled tubing (CT)
and the maximum pressure difference and injection rate (MAPDIR)
methodology.
It is not always realized that the effectiveness of diverters greatly
depends on reservoir properties, such as formation type, temperature,
reservoir permeability, heterogeneity, and physical well
characteristics (e.g., completion type, well deviation, length of
treatment interval, multiple intervals, etc.). This paper reviews the
mechanisms by which each variety of diverter functions and
discusses the effect of various reservoir properties on the efficiency
of diversion techniques. Guidelines are recommended to help
enhance productivity from zones of interest by choosing the best
methods of diversion while pumping an optimized amount of
treatment fluid. The success of an overall acid treatment often
depends on the effectiveness of the diverting agents.
Abstract: A new fuzzy filter is presented for noise reduction of
images corrupted with additive noise. The filter consists of two
stages. In the first stage, all the pixels of image are processed for
determining noisy pixels. For this, a fuzzy rule based system
associates a degree to each pixel. The degree of a pixel is a real
number in the range [0,1], which denotes a probability that the pixel
is not considered as a noisy pixel. In the second stage, another fuzzy
rule based system is employed. It uses the output of the previous
fuzzy system to perform fuzzy smoothing by weighting the
contributions of neighboring pixel values. Experimental results are
obtained to show the feasibility of the proposed filter. These results
are also compared to other filters by numerical measure and visual
inspection.
Abstract: In this paper a unified approach via block-pulse functions (BPFs) or shifted Legendre polynomials (SLPs) is presented to solve the linear-quadratic-Gaussian (LQG) control problem. Also a recursive algorithm is proposed to solve the above problem via BPFs. By using the elegant operational properties of orthogonal functions (BPFs or SLPs) these computationally attractive algorithms are developed. To demonstrate the validity of the proposed approaches a numerical example is included.
Abstract: There are two types of drought as conceptual drought
and operational drought. The three parameters as the beginning, the
end and the degree of severity of the drought can be identifying in
operational drought by average precipitation in the whole region. One
of the methods classified to measure drought is Reconnaissance
Drought Index (RDI). Evapotranspiration is calculated using
Penman-Monteith method by analyzing thirty nine years prolong
climatic data. The evapotranspiration is then utilized in RDI to
classify normalized and standardized RDI. These RDI classifications
led to what kind of drought faced in Bhavnagar region on 12 month
time scale basis. The comparison between actual drought conditions
and RDI method used to find out drought are also illustrated. It can
be concluded that the index results of drought in a particular year are
same in both methods but having different index values where as
severity remain same.
Abstract: The sanitary sewerage connection rate becomes an
important indicator of advanced cities. Following the construction of
sanitary sewerages, the maintenance and management systems are
required for keeping pipelines and facilities functioning well. These
maintenance tasks often require sewer workers to enter the manholes
and the pipelines, which are confined spaces short of natural
ventilation and full of hazardous substances. Working in sewers could
be easily exposed to a risk of adverse health effects. This paper
proposes the use of Bayesian belief networks (BBN) as a higher level
of noncarcinogenic health risk assessment of sewer workers. On the
basis of the epidemiological studies, the actual hospital attendance
records and expert experiences, the BBN is capable of capturing the
probabilistic relationships between the hazardous substances in sewers
and their adverse health effects, and accordingly inferring the
morbidity and mortality of the adverse health effects. The provision of
the morbidity and mortality rates of the related diseases is more
informative and can alleviate the drawbacks of conventional methods.
Abstract: Analytical procedure was carried out in this paper to
calculate the ultimate load capacity of reinforced concrete corbels
strengthened or repaired externally with CFRP sheets. Strut and tie
method and shear friction method proposed earlier for analyzing
reinforced concrete corbels were modified to incorporate the effect of
external CFRP sheets bonded to the corbel. The points of weakness
of any method that lead to an inaccuracy, especially when
overestimating test results were checked and discussed. Comparison
of prediction with the test data indicates that the ratio of test /
calculated ultimate load is 0.82 and 1.17 using strut and tie method
and shear friction method, respectively. If the limits of maximum
shear stress is followed, the calculated ultimate load capacity using
shear friction method was found to underestimates test data
considerably.
Abstract: The measurement of aerodynamic forces and moments
acting on an aircraft model is important for the development of wind
tunnel measurement technology to predict the performance of the full
scale vehicle. The potentials of an aircraft model with and without
winglet and aerodynamic characteristics with NACA wing No. 65-3-
218 have been studied using subsonic wind tunnel of 1 m × 1 m
rectangular test section and 2.5 m long of Aerodynamics Laboratory
Faculty of Engineering (University Putra Malaysia). Focusing on
analyzing the aerodynamic characteristics of the aircraft model, two
main issues are studied in this paper. First, a six component wind
tunnel external balance is used for measuring lift, drag and pitching
moment. Secondly, Tests are conducted on the aircraft model with
and without winglet of two configurations at Reynolds numbers
1.7×105, 2.1×105, and 2.5×105 for different angle of attacks. Fuzzy
logic approach is found as efficient for the representation,
manipulation and utilization of aerodynamic characteristics.
Therefore, the primary purpose of this work was to investigate the
relationship between lift and drag coefficients, with free-stream
velocities and angle of attacks, and to illustrate how fuzzy logic
might play an important role in study of lift aerodynamic
characteristics of an aircraft model with the addition of certain
winglet configurations. Results of the developed fuzzy logic were
compared with the experimental results. For lift coefficient analysis,
the mean of actual and predicted values were 0.62 and 0.60
respectively. The coreelation between actual and predicted values
(from FLS model) of lift coefficient in different angle of attack was
found as 0.99. The mean relative error of actual and predicted valus
was found as 5.18% for the velocity of 26.36 m/s which was found to
be less than the acceptable limits (10%). The goodness of fit of
prediction value was 0.95 which was close to 1.0.
Abstract: This paper adopted the hybrid differential transform approach for studying heat transfer problems in a gold/chromium thin film with an ultra-short-pulsed laser beam projecting on the gold side. The physical system, formulated based on the hyperbolic two-step heat transfer model, covers three characteristics: (i) coupling effects between the electron/lattice systems, (ii) thermal wave propagation in metals, and (iii) radiation effects along the interface. The differential transform method is used to transfer the governing equations in the time domain into the spectrum equations, which is further discretized in the space domain by the finite difference method. The results, obtained through a recursive process, show that the electron temperature in the gold film can rise up to several thousand degrees before its electron/lattice systems reach equilibrium at only several hundred degrees. The electron and lattice temperatures in the chromium film are much lower than those in the gold film.