Abstract: Freshly laid eggs from green turtles, Chelonia mydas,
were randomly collected from Ras Al-Hadd Reserve, Oman.
Eggshells taken from eggs and sand collected from the body chamber
were analyzed for eight heavy metals (Al, Br, Cd, Co, Cu, Fe, S, and
Zn) using inductively coupled plasma mass spectrometry (ICP).
Heavy metal concentrations varied significantly (P
Abstract: The introduction of degradable plastic materials into
agricultural sectors has represented a promising alternative to
promote green agriculture and environmental friendly of modern
farming practices. Major challenges of developing degradable
agricultural films are to identify the most feasible types of
degradation mechanisms, composition of degradable polymers and
related processing techniques. The incorrect choice of degradable
mechanisms to be applied during the degradation process will cause
premature losses of mechanical performance and strength. In order to
achieve controlled process of agricultural film degradation, the
compositions of degradable agricultural film also important in order
to stimulate degradation reaction at required interval of time and to
achieve sustainability of the modern agricultural practices. A set of
photodegradable polyethylene based agricultural film was developed
and produced, following the selective optimization of processing
parameters of the agricultural film manufacturing system. Example of
agricultural films application for oil palm seedlings cultivation is
presented.
Abstract: Fixed-geometry hydrodynamic journal bearings are
one of the best supporting systems for several applications of rotating
machinery. Cylindrical journal bearings present excellent loadcarrying
capacity and low manufacturing costs, but they are subjected
to the oil-film instability at high speeds. An attempt of overcoming
this instability problem has been the development of non-circular
journal bearings. This work deals with an analysis of oil-lubricated
elliptical journal bearings using the finite element method. Steadystate
and dynamic performance characteristics of elliptical bearings
are rendered by zeroth- and first-order lubrication equations obtained
through a linearized perturbation method applied on the classical
Reynolds equation. Four-node isoparametric rectangular finite
elements are employed to model the bearing thin film flow. Curves of
elliptical bearing load capacity and dynamic force coefficients are
rendered at several operating conditions. The results presented in this
work demonstrate the influence of the bearing ellipticity on its
performance at different loading conditions.
Abstract: Incineration of municipal solid waste (MSW) is one of
the key scopes in the global clean energy strategy. A computational
fluid dynamics (CFD) model was established in order to reveal these
features of the combustion process in a fixed porous bed of MSW.
Transporting equations and process rate equations of the waste bed
were modeled and set up to describe the incineration process,
according to the local thermal conditions and waste property
characters. Gas phase turbulence was modeled using k-ε turbulent
model and the particle phase was modeled using the kinetic theory of
granular flow. The heterogeneous reaction rates were determined
using Arrhenius eddy dissipation and the Arrhenius-diffusion
reaction rates. The effects of primary air flow rate and temperature in
the burning process of simulated MSW are investigated
experimentally and numerically. The simulation results in bed are
accordant with experimental data well. The model provides detailed
information on burning processes in the fixed bed, which is otherwise
very difficult to obtain by conventional experimental techniques.
Abstract: In this paper, a direct power control (DPC)
strategies have been investigated in order to control a high
power AC/DC converter with time variable load. This converter
is composed of a three level three phase neutral point clamped
(NPC) converter as rectifier and an H-bridge four quadrant
current control converter. In the high power application,
controller not only must adjust the desire outputs but also
decrease the level of distortions which are injected to the network
from the converter. Regarding to this reason and nonlinearity
of the power electronic converter, the conventional controllers
cannot achieve appropriate responses. In this research, the
precise mathematical analysis has been employed to design the
appropriate controller in order to control the time variable
load. A DPC controller has been proposed and simulated using
Matlab/ Simulink. In order to verify the simulation result, a real
time simulator- OPAL-RT- has been employed. In this paper,
the dynamic response and stability of the high power NPC
with variable load has been investigated and compared with
conventional types using a real time simulator. The results proved
that the DPC controller is more stable and has more precise
outputs in comparison with conventional controller.
Abstract: This paper describes an Action Research project
which was undertaken to inform professional practice in order to
develop a newly created Centre for Student Success in the specific
context of transnational medical and nursing education in the Middle
East. The objectives were to enhance the academic performance,
persistence, integration and personal and professional development of
a multinational study body, in particular in relation to pre-clinical
medical students, and to establish a comfortable, friendly and
student-driven environment within an Irish medical university
recently established in Bahrain. The outcomes of the project resulted
in the development of a specific student success ‘signature’ for this
particular transnational higher education context.
Abstract: Dengue outbreaks are affected by biological,
ecological, socio-economic and demographic factors that vary over
time and space. These factors have been examined separately and still
require systematic clarification. The present study aimed to investigate
the spatial-temporal clustering relationships between these factors and
dengue outbreaks in the northern region of Sri Lanka. Remote sensing
(RS) data gathered from a plurality of satellites were used to develop
an index comprising rainfall, humidity and temperature data. RS data
gathered by ALOS/AVNIR-2 were used to detect urbanization, and a
digital land cover map was used to extract land cover information.
Other data on relevant factors and dengue outbreaks were collected
through institutions and extant databases. The analyzed RS data and
databases were integrated into geographic information systems,
enabling temporal analysis, spatial statistical analysis and space-time
clustering analysis. Our present results showed that increases in the
number of the combination of ecological factor and socio-economic
and demographic factors with above the average or the presence
contribute to significantly high rates of space-time dengue clusters.
Abstract: Using the first-principles full-potential linearized
augmented plane wave plus local orbital (FP-LAPW+lo) method
based on density functional theory (DFT), we have investigated the
electronic structure and magnetism of full Heusler alloys Co2ZrGe
and Co2NbB. These compounds are predicted to be half-metallic
ferromagnets (HMFs) with a total magnetic moment of 2.000 B per
formula unit, well consistent with the Slater-Pauling rule.
Calculations show that both the alloys have an indirect band gaps, in
the minority-spin channel of density of states (DOS), with values of
0.58 eV and 0.47 eV for Co2ZrGe and Co2NbB, respectively.
Analysis of the DOS and magnetic moments indicates that their
magnetism is mainly related to the d-d hybridization between the Co
and Zr (or Nb) atoms. The half-metallicity is found to be relatively
robust against volume changes. In addition, an atom inside molecule
AIM formalism and an electron localization function ELF were also
adopted to study the bonding properties of these compounds, building
a bridge between their electronic and bonding behavior.
As they have a good crystallographic compatibility with the lattice of
semiconductors used industrially and negative calculated cohesive
energies with considerable absolute values these two alloys could be
promising magnetic materials in the spintronic field.
Abstract: Corrosion of concrete sewer pipes induced by sulfuric
acid is an acknowledged problem and a ticking time-bomb to sewer
operators. Whilst the chemical reaction of the corrosion process is
well-understood, the indirect roles of other parameters in the
corrosion process which are found in sewer environment are not
highly reflected on. This paper reports on a field studies undertaken
in Austria and United Kingdom, where the parameters of
temperature, pH, H2S and CO2 were monitored over a period of time.
The study establishes that (i) effluent temperature and pH have
similar daily pattern and peak times, when examined in minutes
scale; (ii) H2S and CO2 have an identical hourly pattern; (iii) H2S
instant or shifted relation to effluent temperature is governed by the
root mean square value of CO2.
Abstract: The main goal of this article is to describe the online
flood monitoring and prediction system Floreon+ primarily developed
for the Moravian-Silesian region in the Czech Republic and the basic
process it uses for running automatic rainfall-runoff and
hydrodynamic simulations along with their calibration and
uncertainty modeling. It takes a long time to execute such process
sequentially, which is not acceptable in the online scenario, so the use
of a high performance computing environment is proposed for all
parts of the process to shorten their duration. Finally, a case study on
the Ostravice River catchment is presented that shows actual
durations and their gain from the parallel implementation.
Abstract: We have been grouping and developing various kinds
of practical, promising sensing applied systems concerning
agricultural advancement and technical tradition (guidance). These
include advanced devices to secure real-time data related to worker
motion, and we analyze by methods of various advanced statistics and
human dynamics (e.g. primary component analysis, Ward system
based cluster analysis, and mapping). What is more, we have been
considering worker daily health and safety issues. Targeted fields are
mainly common farms, meadows, and gardens. After then, we
observed and discussed time-line style, changing data. And, we made
some suggestions. The entire plan makes it possible to improve both
the aforementioned applied systems and farms.
Abstract: Machining of hard materials is a recent technology for
direct production of work-pieces. The primary challenge in
machining these materials is selection of cutting tool inserts which
facilitates an extended tool life and high-precision machining of the
component. These materials are widely for making precision parts for
the aerospace industry. Nickel-based alloys are typically used in
extreme environment applications where a combination of strength,
corrosion resistance and oxidation resistance material characteristics
are required. The present paper reports the theoretical and
experimental investigations carried out to understand the influence of
machining parameters on the response parameters. Considering the
basic machining parameters (speed, feed and depth of cut) a study has
been conducted to observe their influence on material removal rate,
surface roughness, cutting forces and corresponding tool wear.
Experiments are designed and conducted with the help of Central
Composite Rotatable Design technique. The results reveals that for a
given range of process parameters, material removal rate is favorable
for higher depths of cut and low feed rate for cutting forces. Low feed
rates and high values of rotational speeds are suitable for better finish
and higher tool life.
Abstract: The effect of transition metal doping on Pt/Al2O3
catalyst used in propane dehydrogenation reaction at 500°C was
studied. The preparation methods investigated were sequential
impregnation (Pt followed by the 2nd metal or the 2nd metal followed
by Pt) and co-impregnation. The metal contents of these catalysts
were fixed as the weight ratio of Pt per the 2nd metal of around 0.075.
These catalysts were characterized by N2-physisorption, TPR, COchemisorption
and NH3-TPD. It was found that the impregnated 2nd
metal had an effect upon reducibility of Pt due to its interaction with
transition metal-containing structure. This was in agreement with the
CO-chemisorption result that the presence of Pt metal, which is a
result from Pt species reduction, was decreased. The total acidity of
bimetallic catalysts is decreased but the strong acidity is slightly
increased. It was found that the stability of bimetallic catalysts
prepared by co-impregnation and sequential impregnation where the
2nd metal was impregnated before Pt were better than that of
monometallic catalyst (undoped Pt one) due to the forming of Pt sites
located on the transition metal-oxide modified surface. Among all
preparation methods, the sequential impregnation method- having Pt
impregnated before the 2nd metal gave the worst stability because this
catalyst lacked the modified Pt sites and some fraction of Pt sites was
covered by the 2nd metal.
Abstract: Stratified double extreme ranked set sampling
(SDERSS) method is introduced and considered for estimating the
population mean. The SDERSS is compared with the simple random
sampling (SRS), stratified ranked set sampling (SRSS) and stratified
simple set sampling (SSRS). It is shown that the SDERSS estimator
is an unbiased of the population mean and more efficient than the
estimators using SRS, SRSS and SSRS when the underlying
distribution of the variable of interest is symmetric or asymmetric.
Abstract: Degradation of agricultural soils has increased rapidly
during the last 20 years due to the indiscriminate use of pesticides
and other anthropogenic activities. Currently, there is an urgent need
of soil restoration to increase agricultural production. Utilization of
sewage sludge or municipal solid waste is an important way to
recycle nutrient elements and improve soil quality. With these
amendments, nutrient availability in the aqueous phase might be
increased and production of healthier crops can be accomplished.
This research project aimed to achieve sustainable management of
tropical agricultural soils, specifically in Puerto Rico, through the
amendment of water treatment plant sludge’s. This practice avoids
landfill disposal of sewage sludge and at the same time results costeffective
practice for recycling solid waste residues. Coriander
sativum was cultivated in a compost-soil-sludge mixture at different
proportions. Results showed that Coriander grown in a mixture of
25% compost+50% Voladora soi+25% sludge had the best growth
and development. High chlorophyll content (33.01 ± 0.8) was
observed in Coriander plants cultivated in 25% compost+62.5%
Coloso soil+ 12.5% sludge compared to plants grown with no sludge
(32.59 ± 0.7). ICP-OES analysis showed variations in mineral
element contents (macro and micronutrients) in coriander plant
grown I soil amended with sludge and compost.
Abstract: In Jordan having deficit atmospheric precipitation, an
increase in water demand occurs during summer months. Jordan can
be regarded with a relatively high potential for wastewater recycling
and reuse. The main purpose of this paper was to investigate the
removal of total suspended solids (TSS) and chemical oxygen
demand (COD) for olive mill wastewater (OMW) by
electrocoagulation (EC) process. In the combination of
electrocoagulation by using coupled iron–aluminum electrodes, the
optimum working pH was found to be around 6. Results indicated
that the electrocoagulation process allowed removal of TSS and COD
of about 82.5% and 47.5%, respectively at 45 mA/cm2 after 70
minutes by using coupled iron–aluminum electrodes. It was
demonstrated that the maximum TSS and COD removals were
obtained at some optimum experimental parameters for current
density, pH, and reaction time.
Abstract: In this paper, a new design of spherical robotic system
based on the concepts of gimbal structure and gyro dynamics is
presented. Robots equipped with multiple wheels and complex
steering mechanics may increase the weight and degrade the energy
transmission efficiency. In addition, the wheeled and legged robots are
relatively vulnerable to lateral impact and lack of lateral mobility.
Therefore, the proposed robotic design uses a spherical shell as the
main body for ground locomotion, instead of using wheel devices.
Three spherical shells are structured in a similar way to a gimbal
device and rotate like a gyro system. The design and mechanism of the
proposed robotic system is introduced. In addition, preliminary results
of the dynamic model based on the principles of planar rigid body
kinematics and Lagrangian equation are included. Simulation results
and rig construction are presented to verify the concepts.
Abstract: Electronic Word-Of-Mouth (eWOM) communities
represent today an important source of information in which more
and more customers base their purchasing decisions. They include
thousands of reviews concerning very different products and services
posted by many individuals geographically distributed all over the
world. Due to their massive audience, eWOM communities can help
users to find the product they are looking for even if they are less
popular or rare. This is known as the long tail effect, which leads to a
larger number of lower-selling niche products. This paper analyzes
the long tail effect in a well-known eWOM community and defines a
tool for finding niche products unavailable through conventional
channels.
Abstract: An experimental study was performed to investigate
the behavior and strength of proposed technique to connect
reinforced concrete (RC) beam to steel or composite columns. This
approach can practically be used in several types of building
construction. In this technique, the main beam of the frame consists
of a transfer part (part of beam; Tr.P) and a common reinforcement
concrete beam. The transfer part of the beam is connected to the
column, whereas the rest of the beam is connected to the transfer part
from each side. Four full-scale beam-column connections were tested
under static loading. The test parameters were the length of the
transfer part and the column properties. The test results show that
using of the transfer part technique leads to modify the deformation
capabilities for the RC beam and hence it increases its resistance
against failure. Increase in length of the transfer part did not
necessarily indicate an enhanced behavior. The test results contribute
to the characterization of the connection behavior between RC beam -
steel column and can be used to calibrate numerical models for the
simulation of this type of connection.
Abstract: Ionic liquids consisting of a phosphonium cationic
moiety and a saccharinate anion are synthesized and compared with
their precursors, phosphonium chlorides, in reference to their
extraction efficiency towards L-lactic acid. On the base of
measurements of the acid and the water partitioning in the
equilibrium biphasic systems, the molar ratios between acid, water
and ionic liquid are estimated which allows to deduce the lactic acid
extractive pathway. The effect of a salting-out addition that
strengthens hydrophobicity in both phases is studied in view to reveal
the best biphasic system with respect to IL low toxicity and high
extraction efficiency.