Abstract: This paper deals with the theoretical and numerical
investigation of magneto hydrodynamic boundary layer flow of a
nanofluid past a wedge shaped wick in heat pipe used for the cooling
of electronic components and different type of machines. To
incorporate the effect of nanoparticle diameter, concentration of
nanoparticles in the pure fluid, nanothermal layer formed around the
nanoparticle and Brownian motion of nanoparticles etc., appropriate
models are used for the effective thermal and physical properties of
nanofluids. To model the rotation of nanoparticles inside the base
fluid, microfluidics theory is used. In this investigation ethylene
glycol (EG) based nanofluids, are taken into account. The non-linear
equations governing the flow and heat transfer are solved by using a
very effective particle swarm optimization technique along with
Runge-Kutta method. The values of heat transfer coefficient are
found for different parameters involved in the formulation viz.
nanoparticle concentration, nanoparticle size, magnetic field and
wedge angle etc. It is found that, the wedge angle, presence of
magnetic field, nanoparticle size and nanoparticle concentration etc.
have prominent effects on fluid flow and heat transfer characteristics
for the considered configuration.
Abstract: Reliability of long-term storage products is related to
the availability of the whole system, and the evaluation of storage life
is of great necessity. These products are usually highly reliable and
little failure information can be collected. In this paper, an analytical
method based on data from accelerated storage life test is proposed to
evaluate the reliability index of the long-term storage products. Firstly,
singularities are eliminated by data normalization and residual
analysis. Secondly, with the preprocessed data, the degradation path
model is built to obtain the pseudo life values. Then by life distribution
hypothesis, we can get the estimator of parameters in high stress levels
and verify failure mechanism consistency. Finally, the life distribution
under the normal stress level is extrapolated via the acceleration model
and evaluation of the actual average life is available. An application
example with the camera stabilization device is provided to illustrate
the methodology we proposed.
Abstract: Propylene self-metathesis to ethylene and butene was
studied over WOx/SiO2 catalysts at 450oC and atmospheric pressure.
The WOx/SiO2 catalysts were prepared by incipient wetness
impregnation of ammonium metatungstate aqueous solution. It was
found that, adding nano-sized extra supports (SiO2 and TiO2) by
physical mixing with the WOx/SiO2 enhanced propylene conversion.
The UV-Vis and FT-Raman results revealed that WOx could migrate
from the original silica support to the extra support, leading to a
better dispersion of WOx. The ICP-OES results also indicate that
WOx existed on the extra support. Coke formation was investigated
on the catalysts after 10 h time-on-stream by TPO. However, adding
nano-sized extra supports led to higher coke formation which may be
related to acidity as characterized by NH3-TPD.
Abstract: All the software engineering researches and best
industry practices aim at providing software products with high
degree of quality and functionality at low cost and less time. These
requirements are addressed by the Component Based Software
Engineering (CBSE) as well. CBSE, which deals with the software
construction by components’ assembly, is a revolutionary extension
of Software Engineering. CBSE must define and describe processes
to assure timely completion of high quality software systems that are
composed of a variety of pre built software components. Though
these features provide distinct and visible benefits in software design
and programming, they also raise some challenging problems. The
aim of this work is to summarize the pertinent issues and
considerations in CBSE to make an understanding in forms of
concepts and observations that may lead to development of newer
ways of dealing with the problems and challenges in CBSE.
Abstract: Alone with fast urbanization in world, traffic control
became a big issue in urban construction. Having an efficient and
reliable traffic control system is crucial to macro-traffic control.
Traffic signal is used to manage conflicting requirement by allocating
different sets of mutually compatible traffic movement during distinct
time interval. Many approaches have been made proposed to solve
this discrete stochastic problem. Recognizing the need to minimize
right-of-way impacts while efficiently handling the anticipated high
traffic volumes, the proposed alternative system gives effective
design. This model allows for increased traffic capacity and reduces
delays by eliminating a step in maneuvering through the freeway
interchange. The concept proposed in this paper involves
construction of bridges and ramps at intersection of four roads to
control the vehicular congestion and to prevent traffic breakdown.
Abstract: In this article, the antibiogram and heavy metal
resistance profile of the bacteria isolated from total 34 studied
animals (Pelophylax ridibundus = 12; Mauremys rivulata = 14;
Natrix natrix = 8) captured around the Biga Stream, are described.
There was no database information on antibiogram and heavy metal
resistance profile of bacteria from these area’s amphibians and
reptiles.
A total of 200 bacteria were successfully isolated from cloaca and
oral samples of the aquatic amphibians and reptiles as well as from
the water sample. According to Jaccard’s similarity index, the degree
of similarity in the bacterial flora was quite high among the
amphibian and reptile species under examination, whereas it was
different from the bacterial diversity in the water sample. The most
frequent isolates were A. hydrophila (31.5%), B. pseudomallei
(8.5%), and C. freundii (7%). The total numbers of bacteria obtained
were as follows: 45 in P. ridibundus, 45 in N. natrix 30 in M.
rivulata, and 80 in the water sample. The result showed that
cefmetazole was the most effective antibiotic to control the bacteria
isolated in this study and that approximately 93.33% of the bacterial
isolates were sensitive to this antibiotic. The multiple antibiotic
resistances (MAR) index indicated that P. ridibundus (0.95) > N.
natrix (0.89) > M. rivulata (0.39). Furthermore, all the tested heavy
metals (Pb+2, Cu+2, Cr+3, and Mn+2) inhibit the growth of the bacterial
isolates at different rates. Therefore, it indicated that the water source
of the animals was contaminated with both antibiotic residues and
heavy metals.
Abstract: Exact solution of an unsteady MHD flow of elasticoviscous
fluid through a porous media in a tube of spherical cross
section under the influence of magnetic field and constant pressure
gradient has been obtained in this paper. Initially, the flow is
generated by a constant pressure gradient. After attaining the steady
state, the pressure gradient is suddenly withdrawn and the resulting
fluid motion in a tube of spherical cross section by taking into
account of the porosity factor and magnetic parameter of the
bounding surface is investigated. The problem is solved in two-stages
the first stage is a steady motion in tube under the influence of a
constant pressure gradient, the second stage concern with an unsteady
motion. The problem is solved employing separation of variables
technique. The results are expressed in terms of a non-dimensional
porosity parameter (K), magnetic parameter (m) and elasticoviscosity
parameter (β), which depends on the Non-Newtonian
coefficient. The flow parameters are found to be identical with that of
Newtonian case as elastic-viscosity parameter and magnetic
parameter tends to zero and porosity tends to infinity. It is seen that
the effect of elastico-viscosity parameter, porosity parameter and
magnetic parameter of the bounding surface has significant effect on
the velocity parameter.
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: Reliability allocation is quite important during early
design and development stages for a system to apportion its specified
reliability goal to subsystems. This paper improves the reliability
fuzzy allocation method, and gives concrete processes on determining
the factor and sub-factor sets, weight sets, judgment set, and
multi-stage fuzzy evaluation. To determine the weight of factor and
sub-factor sets, the modified trapezoidal numbers are proposed to
reduce errors caused by subjective factors. To decrease the fuzziness
in fuzzy division, an approximation method based on linear
programming is employed. To compute the explicit values of fuzzy
numbers, centroid method of defuzzification is considered. An
example is provided to illustrate the application of the proposed
reliability allocation method based on fuzzy arithmetic.
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: We present a framework of researcher knowledge
development in conducting a study in mathematics education. The
key components of the framework are: knowledge germane to
conducting a particular study, processes of knowledge accumulation,
and catalyzing filters that influence a researcher decision making.
The components of the framework originated from a confluence
between constructs and theories in Mathematics Education, Higher
Education and Sociology. Drawing on a self-reflective interview with
a leading researcher in mathematics education, Professor Michèle
Artigue, we illustrate how the framework can be utilized in data
analysis. Criteria for framework evaluation are discussed.
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: 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: High gain broadband plasmonic slot nano-antenna has
been considered. The theory of plasmonic slot nano-antenna (PSNA)
has been developed. The analytical model takes into account also the
electrical field inside the metal due to imperfectness of metal in
optical range, as well as numerical investigation based on finite
element method (FEM) has been realized. It should be mentioned that
Yagi-Uda configuration improves directivity in the plane of structure.
In contrast, in this paper the possibility of directivity improvement of
proposed PSNA in perpendicular plane of structure by using
reflection metallic surface placed under the slot in fixed distance has
been demonstrated. It is well known that a directivity improvement
brings to the antenna gain increasing. This method of diagram
improving is also well known from RF antenna design theory.
Moreover the improvement of directivity in the perpendicular plane
gives more flexibility in such application as improving the light and
atom, ion, molecule interactions by using such type of plasmonic slot
antenna. By the analogy of dipole type optical antennas the widening
of working wavelengths has been realized by using bowtie geometry
of slots, which made the antenna broadband.
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: In this paper, a numerical simulation of a finned store
separating from a wing-pylon configuration has been studied and
validated. A dynamic unstructured tetrahedral mesh approach is
accomplished by using three grid sizes to numerically solving the
discretized three dimensional, inviscid and compressible Euler
equations. The method used for computations of separation of an
external store assuming quasi-steady flow condition. Computations of
quasi-steady flow have been directly coupled to a six degree-offreedom
(6DOF) rigid-body motion code to generate store
trajectories. The pressure coefficients at four different angular cuts
and time histories of various trajectory parameters and wing pressure
distribution during the store separation are compared for every grid
size with published experimental data.
Abstract: Experimental production methods of Chevreul’s salt
being an intermediate stage product in copper recovery were
investigated on this article. Chevreul’s salt, Cu2SO3.CuSO3.2H2O,
being a mixed valence copper sulphite compound, has been obtained
by using different methods and reagents. Chevreul’s salt has an
intense brick-red color. It is highly stable and expensive. The
production of Chevreul’s salt plays a key role in hydrometallurgy.
Thermodynamic tendency on precipitation of Chevreul’s salt is
related to pH and temperature. Besides, SO2 gaseous is a versatile
reagent for precipitating of copper sulphites, Using of SO2 for
selective precipitation can be made by appropriate adjustments of pH
and temperature. Chevreul’s salt does not form in acidic solutions if
those solutions contains considerable amount of sulfurous acid. It is
necessary to maintain between pH 2–4.5, because, solubility of
Chevreul’s salt increases with decreasing of pH values. Also, the
region which Chevreul’s salt is stable can be seen from the potentialpH
diagram.
Abstract: Nanofibers of PVA /nickel nitrate/silica/alumina
izopropoxide/boric acid composite were prepared by using sol-gel
processing and electrospinning technique. By high temperature
calcinations of the above precursor fibers, nanofibers of
NiO/Al2O3/B2O3/SiO2 composite with diameters about 500 nm
could be successfully obtained. The fibers were characterized by
XRD and SEM analyses.
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.