Abstract: Subspace channel estimation methods have been
studied widely, where the subspace of the covariance matrix is
decomposed to separate the signal subspace from noise subspace. The
decomposition is normally done by using either the eigenvalue
decomposition (EVD) or the singular value decomposition (SVD) of
the auto-correlation matrix (ACM). However, the subspace
decomposition process is computationally expensive. This paper
considers the estimation of the multipath slow frequency hopping
(FH) channel using noise space based method. In particular, an
efficient method is proposed to estimate the multipath time delays by
applying multiple signal classification (MUSIC) algorithm which is
based on the null space extracted by the rank revealing LU (RRLU)
factorization. As a result, precise information is provided by the
RRLU about the numerical null space and the rank, (i.e., important
tool in linear algebra). The simulation results demonstrate the
effectiveness of the proposed novel method by approximately
decreasing the computational complexity to the half as compared
with RRQR methods keeping the same performance.
Abstract: The main objective of this paper is to provide a new
methodology for road safety assessment in Oman through the
development of suitable accident prediction models. GLM technique
with Poisson or NBR using SAS package was carried out to develop
these models. The paper utilized the accidents data of 31 un-signalized
T-intersections during three years. Five goodness-of-fit
measures were used to assess the overall quality of the developed
models. Two types of models were developed separately; the flow-based
models including only traffic exposure functions, and the full
models containing both exposure functions and other significant
geometry and traffic variables.
The results show that, traffic exposure functions produced much
better fit to the accident data. The most effective geometric variables
were major-road mean speed, minor-road 85th percentile speed,
major-road lane width, distance to the nearest junction, and right-turn
curb radius.
The developed models can be used for intersection treatment or
upgrading and specify the appropriate design parameters of T-intersections.
Finally, the models presented in this thesis reflect the intersection
conditions in Oman and could represent the typical conditions in
several countries in the middle east area, especially gulf countries.
Abstract: Taiwan is a hyper endemic area for the Hepatitis B
virus (HBV). The estimated total number of HBsAg carriers in the
general population who are more than 20 years old is more than 3
million. Therefore, a case record review is conducted from January
2003 to June 2007 for all patients with a diagnosis of acute hepatitis
who were admitted to the Emergency Department (ED) of a
well-known teaching hospital. The cost for the use of medical
resources is defined as the total medical fee. In this study, principal
component analysis (PCA) is firstly employed to reduce the number of
dimensions. Support vector regression (SVR) and artificial neural
network (ANN) are then used to develop the forecasting model. A total
of 117 patients meet the inclusion criteria. 61% patients involved in
this study are hepatitis B related. The computational result shows that
the proposed PCA-SVR model has superior performance than other
compared algorithms. In conclusion, the Child-Pugh score and
echogram can both be used to predict the cost of medical resources for
patients with acute hepatitis in the ED.
Abstract: This study examined how individuals in their
respective teams contributed to innovation performance besides
defining the term of innovation in their own respective views. This
study also identified factors that motivated University staff to
contribute to the innovation products. In addition, it examined
whether there is a significant relationship between professional
training level and the length of service among university staff
towards innovation and to what extent do the two variables
contributed towards innovative products. The significance of this
study is that it revealed the strengths and weaknesses of the
university staff when contributing to innovation performance.
Stratified-random sampling was employed to determine the samples
representing the population of lecturers in the study, involving 123
lecturers in one of the local universities in Malaysia. The method
employed to analyze the data is through categorizing into themes for
the open-ended questions besides using descriptive and inferential
statistics for the quantitative data. This study revealed that two types
of definition for the term “innovation” exist among the university
staff, namely, creation of new product or new approach to do things
as well as value-added creative way to upgrade or improve existing
process and service to be more efficient. This study found that the
most prominent factor that propels them towards innovation is to
improve the product in order to benefit users, followed by selfsatisfaction
and recognition. This implies that the staff in the
organization viewed the creation of innovative products as a process
of growth to fulfill the needs of others and also to realize their
personal potential. This study also found that there was only a
significant relationship between the professional training level and
the length of service of 4 - 6 years among the university staff. The
rest of the groups based on the length of service showed that there
was no significant relationship with the professional training level
towards innovation. Moreover, results of the study on directional
measures depicted that the relationship for the length of service of 4-
6 years with professional training level among the university staff is
quite weak. This implies that good organization management lies on
the shoulders of the key leaders who enlighten the path to be
followed by the staff.
Abstract: In 2010-2011, the research on zooplankton was
conducted in the southern part of the Baltic Sea to determine seasonal
variability in changes occurring throughout the zooplankton in 2010
and 2011, both in the region of Gdańsk Deep, and in the western part
of Gdańsk Bay. The research in the sea showed that the taxonomic
composition of holoplankton in the southern part of the Baltic Sea
was similar to that recorded in this region for many years. The
maximum values of abundance and biomass of zooplankton both in
the Deep and the Bay of Gdańsk were observed in the summer
season. Copepoda dominated in the composition of zooplankton for
almost the entire study period, while rotifers occurred in larger
numbers only in the summer 2010 in the Gdańsk Deep as well as in
May and July 2010 in the western part of Gdańsk Bay, and
meroplankton – in April 2011.
Abstract: The performance of box-type solar cookers has been
reported by several researchers but little attention was paid to the
effect of the type of insulation material on the energy and exergy
efficiency of these cookers. This research aimed at evaluating the
energy and exergy efficiencies of the box-type cookers containing
different insulation materials. Energy and exergy efficiencies of five
box-type solar cookers insulated with maize cob, air (control), maize
husk, coconut coir and polyurethane foam respectively were obtained
over a period of three years. The cookers were evaluated using water
heating test procedures in determining the energy and exergy
analysis. The results were subjected to statistical analysis using
ANOVA. The result shows that the average energy input for the five
solar cookers were: 245.5, 252.2, 248.7, 241.5 and 245.5J
respectively while their respective average energy losses were: 201.2,
212.7, 208.4, 189.1 and 199.8J. The average exergy input for five
cookers were: 228.2, 234.4, 231.1, 224.4 and 228.2J respectively
while their respective average exergy losses were: 223.4, 230.6,
226.9, 218.9 and 223.0J. The energy and exergy efficiency was
highest in the cooker with coconut coir (37.35 and 3.90%
respectively) in the first year but was lowest for air (11 and 1.07%
respectively) in the third year. Statistical analysis showed significant
difference between the energy and exergy efficiencies over the years.
These results reiterate the importance of a good insulating material
for a box-type solar cooker.
Abstract: This paper presents a novel integrated hybrid
approach for fault diagnosis (FD) of nonlinear systems. Unlike most
FD techniques, the proposed solution simultaneously accomplishes
fault detection, isolation, and identification (FDII) within a unified
diagnostic module. At the core of this solution is a bank of adaptive
neural parameter estimators (NPE) associated with a set of singleparameter
fault models. The NPEs continuously estimate unknown
fault parameters (FP) that are indicators of faults in the system. Two
NPE structures including series-parallel and parallel are developed
with their exclusive set of desirable attributes. The parallel scheme is
extremely robust to measurement noise and possesses a simpler, yet
more solid, fault isolation logic. On the contrary, the series-parallel
scheme displays short FD delays and is robust to closed-loop system
transients due to changes in control commands. Finally, a fault
tolerant observer (FTO) is designed to extend the capability of the
NPEs to systems with partial-state measurement.
Abstract: Our globalizing world has become almost a small
village and everyone can access any information at any time.
Everyone lets each other know who does whatever in which place.
We can learn which social events occur in which place in the world.
From the perspective of education, the course notes that a lecturer use
in lessons in a university in any state of America can be examined by
a student studying in a city of Africa or the Far East. This dizzying
communication we have mentioned happened thanks to fast
developments in computer and internet technologies. While these
developments occur in the world, Turkey that has a very large young
population and whose electronic infrastructure rapidly improves has
also been affected by these developments. Nowadays, mobile devices
have become common and thus, it causes to increase data traffic in
social networks. This study was carried out on students in the
different age groups in Selcuk University Vocational School of
Technical Sciences, the Department of Computer Technology.
Students’ opinions about the use of internet and social media were
obtained. The features such as using the Internet and social media
skills, purposes, operating frequency, accessing facilities and tools,
social life and effects on vocational education and so forth were
explored. The positive effects and negative effects of both internet
and social media use on the students in this department and findings
are evaluated from different perspectives and results are obtained. In
addition, relations and differences were found out statistically.
Abstract: In this paper, the effects of fiber types and elevated
temperatures on compressive strength, modulus of rapture and the
bond characteristics of fiber reinforced concretes (FRC) are
presented. By using the three different types of fibers (steel fiber-SF,
polypropylene-PPF and polyvinyl alcohol-PVA), FRC specimens
were produced and exposed to elevated temperatures up to 800 ºC for
1.5 hours. In addition, a plain concrete (without fiber) was produced
and used as a control. Test results obtained showed that the steel fiber
reinforced concrete (SFRC) had the highest compressive strength,
modulus of rapture and bond stress values at room temperatures, the
residual bond, flexural and compressive strengths of both FRC and
plain concrete dropped sharply after exposure to high temperatures.
The results also indicated that the reduction of bond, flexural and
compressive strengths with increasing the exposed temperature was
relatively less for SFRC than for plain, and FRC with PPF and PVA.
Abstract: The aim of this paper is to present the optimization
methodology developed in the frame of a Coastal Transport
Information System. The system will be used for the effective design
of coastal transportation lines and incorporates subsystems that
implement models, tools and techniques that may support the design
of improved networks. The role of the optimization and decision
subsystem is to provide the user with better and optimal scenarios
that will best fulfill any constrains, goals or requirements posed. The
complexity of the problem and the large number of parameters and
objectives involved led to the adoption of an evolutionary method
(Genetic Algorithms). The problem model and the subsystem
structure are presented in detail, and, its support for simulation is also
discussed.
Abstract: This paper presents experimental investigation and
finite element analysis on buckling behavior of irregular section coldformed
steel columns under axially concentric loading. For the
experimental study, four different sections of columns were tested to
investigate effect of stiffening and width-to-thickness ratio on
buckling behavior. For each of the section, three lengths of 230, 950
and 1900 mm. were studied representing short, intermediate long and
long columns, respectively. Then, nonlinear finite element analyses
of the tested columns were performed. The comparisons in terms of
load-deformation response and buckling mode show good agreement
and hence the FEM models were validated. Parametric study of
stiffening element and thickness of 1.0, 1.15, 1.2, 1.5, 1.6 and 2.0
mm. was analyzed. The test results showed that stiffening effect pays
a large contribution to prevent distortional mode. The increase in wall
thickness enhanced buckling stress beyond the yielding strength in
short and intermediate columns, but not for the long columns.
Abstract: The textile industry plays a major role in the economy
of India and on the other side of the coin it is the major source for
water pollution. As azo dyes is the largest dye class they are
extensively used in many fields such as textile industry, leather
tanning industry, paper production, food, color photography,
pharmaceuticals and medicine, cosmetic, hair colorings, wood
staining, agricultural, biological and chemical research etc. In
addition to these, they can have acute and/or chronic effects on
organisms depending on their concentration and length of exposure
when they discharged as effluent in the environment. The aim of this
study was to assess the genotoxic and histotoxic potentials of
environmentally relevant concentrations of C. I. Reactive Red 120
(RR 120) on Catla catla, important edible freshwater fingerlings. For
this, healthy Catla catla fingerlings were procured from the
Government Fish Farm and acclimatized in 100 L capacity and
continuously aerated glass aquarium in laboratory for 15 days.
According to APHA some physic-chemical parameters were
measured and maintained such as temperature, pH, dissolve oxygen,
alkalinity, total hardness. Water along with excreta had been changed
every 24 hrs. All fingerlings were fed artificial food palates once a
day @ body weight. After 15 days fingerlings were grouped in 5 (10
in each) and exposed to various concentrations of RR 120 (Control,
10, 20, 30 and 40 mg.l-1) and samples (peripheral blood and gills,
kidney) were collected and analyzed at 96 hrs. All results were
compared with the control. Micronuclei (MN), nuclear buds (NB),
fragmented-apoptotic (FA) and bi-nucleated (BN) cells in blood
smears and in tissues (gills and kidney cells) were observed.
Prominent histopathological alterations were noticed in gills such as
aneurism, hyperplasia, degenerated central axis, lifting of gill
epithelium, curved secondary gill lamellae etc. Similarly kidney
showed some detrimental changes like shrunken glomeruli with
increased periglomerular space, degenerated renal tubules etc. Both
haematological and histopathological changes clearly reveal the toxic
potential of RR 120. This work concludes that water pollution
assessment can be done by these two biomarkers which provide
baseline to the further chromosomal or molecular work.
Abstract: Verification of vented wooden façade system with
bonded joints is presented in this paper. The potential of bonded
joints is studied and described in more detail. The paper presents the results of an experimental and theoretical research about the effects of freeze cycling on the bonded joint. For the purpose of tests spruce
timber profiles were chosen for the load bearing substructure. Planks from wooden plastic composite and Siberian larch are representing facade cladding. Two types of industrial polyurethane adhesives intended for structural bonding were selected. The article is focused on the preparation as well as on the subsequent curing and conditioning of test samples. All test samples were subjected to 15 cycles that represents sudden temperature changes, i.e. immersion in a water bath at (293.15 ± 3) K for 6 hours and subsequent freezing to (253.15 ± 2) K for 18 hours. Furthermore, the retention of bond strength between substructure and cladding wastested and strength in shear was determined under tensile stress.Research data indicate that little, if any, damage to the bond results from freezingcycles. Additionally, the suitability of selected group of adhesives in combination with timber substructure was confirmed.
Abstract: Depositional environment and source potential of the
different organic-rich levels of Devonian age (up to 990m thick) from
the onshore EC-1 well (Southern Tunisia) were investigated based on
the analysis of more than 130 cutting samples by different
geochemical techniques (Rock-Eval pyrolysis, GC-MS). The
obtained results including Rock Eval Pyrolysis data and biomarker
distribution (terpanes, steranes and aromatics) have been used to
describe the depositional environment and to assess the thermal
maturity of the Devonian organic matter. These results show that the
Emsian deposits exhibit poor to fair TOC contents. The associated
organic matter is composed of mixed kerogen (type II/III), as
indicated by the predominance of C29 steranes over C27 and C28
homologous, that was deposited in a slightly reduced environment
favoring organic matter preservation. Thermal maturity assessed from
Tmax, TNR and MPI-1 values shows a mature stage of organic
matter. The Middle Devonian (Eifelian) shales are rich in type II
organic matter that was deposited in an open marine depositional
environment. The TOC values are high and vary between 2 and 7%
indicating good to excellent source rock. The relatively high HI
values (reaching 547 mg HC/g TOC) and the low values of t19/t23
tricyclic terpane ratio (< 0.2) confirm the marine origin of the organic
matter (type II). During the Upper Devonian, the organic matter was
deposited under variable redox conditions, oxic to suboxic which is
clearly indicated by the low C35/C34 hopanes ratio, immature to
marginally mature with the vitrinite reflectance ranging from 0.5 to
0.7 Ro and Tmax value of 426°C-436 °C and the TOC values range
between 0.8% to 4%.
Abstract: After the internet explosion in the 90’s, technology
was immediately integrated into the school system. Technology
which symbolizes advancement in human knowledge was seen as a
setback by many educators. Efforts have been made to help stem this
erroneous believes and help educators realize the benefits of
technology and ways of implementing it in the classrooms especially
in the sciences. This advancement created a constantly expanding gap
between the pupil’s perception on the use of technology within the
learning atmosphere and the teacher’s perception and limitations
hence, the focus of this paper is on the need to refocus on the use of
Science and Technology in enhancing children’s potentials in
learning at school especially in Science for sustainable development
in Nigeria. The paper recommended measures for facilitating the
sustenance of science and technology in Nigerian schools so as to
enhance the potentials of our children in Science and Technology for
a better tomorrow.
Abstract: Taking into account the significance of measuring the
daily use of the study space in the libraries in order to develop and
reorganize the space for enhancing the efficiency of the study space,
the current study aimed to apply GIS in analyzing the study halls of
the Central Library and Document Center of Tehran University in
order to determine how study desks and chairs were used by the
students. The study used a combination of survey-descriptive and
system design method. In order to gather the required data, surveydescriptive
method was used. For implementing and entering data
into ArcGIS and analyzing the data and displaying the results on the
maps of the study halls of the library, system design method was
utilized. The design of the spatial database of the use of the study
halls was measured through the extent of occupancy of the space by
the library users and the maps of the study halls of the central library
of Tehran University as the case study. The results showed that
Abooreyhan hall had the highest rate of occupancy of the desks and
chairs compared to the other halls. The Hall of Science and
Technology, with an average occupancy rate of 0.39 for the tables
represented the lowest number of users and Rashid al-Dins hall, and
Science and Technology hall with an average occupancy rate (0.40)
had the lowest number of users for seats. In this study, the
comparison of the space occupied at different periods in the morning,
evenings, afternoons, and several months was performed through
GIS. This system analyzed the space relationships effectively and
efficiently. The output of this study would be used by administrators
and librarians to determine the exact extent of use of the equipment
of the study halls and librarians can use the output map to design the
space more efficiently at the library.
Abstract: The mechanisms underlying the association between
obesity and asthma may be related to a decreased immunological
tolerance induced by a defective function of regulatory T cells
(Tregs). The aim of this study is to establish the potential link
between these diseases and CD4+, CD25+ FoxP3+ Tregs as well as T
helper cells (Ths) in children. This is a prospective case control
study. Obese (n:40), asthmatic (n:40), asthmatic obese (n:40) and
healthy children (n:40), who don't have any acute or chronic diseases,
were included in this study. Obese children were evaluated according
to WHO criteria. Asthmatic patients were chosen based on GINA
criteria. Parents were asked to fill up the questionnaire. Informed
consent forms were taken. Blood samples were marked with CD4+,
CD25+ and FoxP3+ in order to determine Tregs and Ths by flow
cytometric method. Statistical analyses were performed. p≤0.05 was
chosen as meaningful threshold. Tregs exhibiting anti-inflammatory
nature were significantly lower in obese (0,16%; p≤0,001), asthmatic
(0,25%; p≤0,01) and asthmatic obese (0,29%; p≤0,05) groups than
the control group (0,38%). Ths were counted higher in asthma group
than the control (p≤0,01) and obese (p≤0,001) groups. T cell
immunity plays important roles in obesity and asthma pathogeneses.
Decreased numbers of Tregs found in obese, asthmatic and asthmatic
obese children may help to elucidate some questions in
pathophysiology of these diseases. For HOMA-IR levels, any
significant difference was not noted between control and obese
groups, but statistically higher values were found for obese
asthmatics. The values obtained in all groups were found to be below
the critical cut off points. This finding has made the statistically
significant difference observed between Tregs of obese, asthmatic,
obese asthmatic and control groups much more valuable. These
findings will be useful in diagnosis and treatment of these disorders
and future studies are needed. The production and propagation of
Tregs may be promising in alternative asthma and obesity treatments.
Abstract: Increasing prevalence of childhood obesity has
increased the interest in early and late indicators of gaining weight.
Cell blood counts may be indicators of pro-inflammatory states. The
aim was to evaluate associations of hematological parameters,
including hematocrit (HTC), hemoglobin, blood cell counts and their
indices with the degree of obesity in pediatric population. A total of
249; -139 morbidly obese (MO), 82 healthy normal weight (NW) and
28 overweight (OW) children were included into the scope of the
study. WHO BMI-for age percentiles were used to form age- and sexmatched
groups. Informed consent forms and the Ethics Committee
approval were obtained. Anthropometric measurements were
performed. Hematological parameters were determined. Statistical
analyses were performed using SPSS. The degree for statistical
significance was p≤0.05. Significant differences (p=0.000) between
waist-to-hip ratios and head-to- neck ratios (hnrs) of MO and NW
children were detected. A significant difference between hnrs of OW
and MO children (p=0.000) was observed. Red cell distribution width
(RDW) was higher in OW children than NW group (p=0.030). Such
finding couldn’t be detected between MO and NW groups. Increased
RDW was prominent in OW children. The decrease in mean
corpuscular hemoglobin concentration (MCHC) values in MO
children was sharper than the values in OW children (p=0.006 vs
p=0.042) compared to those in NW group. Statistically higher HTC
levels were observed between MO-NW (p=0.014), but none between
OW-NW. Though the cause-effect relationship between obesity and
erythrocyte indices still needs further investigation, alterations in
RDW, HTC, MCHC during obesity may be of significance in the
early life.
Abstract: Experimental study of natural convection heat transfer
inside smooth and rough surfaces of vertical and inclined equilateral
triangular channels of different inclination angles with a uniformly
heated surface are performed. The inclination angle is changed from
15º to 90º. Smooth and rough surface of average roughness (0.02mm)
are used and their effect on the heat transfer characteristics are
studied. The local and average heat transfer coefficients and Nusselt
number are obtained for smooth and rough channels at different heat
flux values, different inclination angles and different Rayleigh
numbers (Ra) 6.48 × 105 ≤ Ra ≤ 4.78 × 106. The results show that
the local Nusselt number decreases with increase of axial distance
from the lower end of the triangular channel to a point near the upper
end of channel, and then, it slightly increases. Higher values of local
Nusselt number for rough channel along the axial distance compared
with the smooth channel. The average Nusselt number of rough
channel is higher than that of smooth channel by about 8.1% for
inclined case at θ = 45o and 10% for vertical case. The results
obtained are correlated using dimensionless groups for both rough
and smooth surfaces of the inclined and vertical triangular channels.
Abstract: In the current work, a three-dimensional geometry of a
75% stenosed blood vessel is analyzed. Large eddy simulation (LES)
with the help of a dynamic subgrid scale Smagorinsky model is
applied to model the turbulent pulsatile flow. The geometry, the
transmural pressure and the properties of the blood and the elastic
boundary were based on clinical measurement data. For the flexible
wall model, a thin solid region is constructed around the 75%
stenosed blood vessel. The deformation of this solid region was
modelled as a deforming boundary to reduce the computational cost
of the solid model. Fluid-structure interaction is realized via a twoway
coupling between the blood flow modelled via LES and the
deforming vessel. The information of the flow pressure and the wall
motion was exchanged continually during the cycle by an arbitrary
Lagrangian-Eulerian method. The boundary condition of current time
step depended on previous solutions. The fluctuation of the velocity
in the post-stenotic region was analyzed in the study. The axial
velocity at normalized position Z=0.5 shows a negative value near
the vessel wall. The displacement of the elastic boundary was
concerned in this study. In particular, the wall displacement at the
systole and the diastole were compared. The negative displacement at
the stenosis indicates a collapse at the maximum velocity and the
deceleration phase.