Abstract: In order to utilize results from global climate models,
dynamical and statistical downscaling techniques have been
developed. For dynamical downscaling, usually a limited area
numerical model is used, with associated high computational cost.
This research proposes dynamic equation for specific space-time
regional climate downscaling from the Educational Global Climate
Model (EdGCM) for Southeast Asia. The equation is for surface air
temperature. This equation provides downscaling values of surface
air temperature at any specific location and time without running a
regional climate model. In the proposed equations, surface air
temperature is approximated from ground temperature, sensible heat
flux and 2m wind speed. Results from the application of the equation
show that the errors from the proposed equations are less than the
errors for direct interpolation from EdGCM.
Abstract: This study focuses on the stress analysis of Mandibular
Advancement Devices (MADs), which are considered as a standard
treatment of snoring that promoted by American Academy of Sleep
Medicine (AASM). Snoring is the most significant feature of
sleep-disordered breathing (SDB). SDB will lead to serious problems
in human health. Oral appliances are ensured in therapeutic effect and
compliance, especially the MADs. This paper proposes a new MAD
design, and the finite element analysis (FEA) is introduced to precede
the stress simulation for this MAD.
Abstract: A psychological contract is an agreement between the
employer and an employee that covers the parties’ informal and
frequently non-verbalized obligations and expectations towards each
other. The contract is a cognitive pattern-governing employee’s
behaviour in the organization. A gap between employee’s
expectations and the organizational reality may lead to difficult-to-solve
conflicts or cause the employee to modify their behaviour
towards organizational values and goals, if they are willing and ready
to verbalize their expectations. The article discusses psychological contracts in the financial
institutions in Poland. Its theoretical part outlines the types of
psychological contracts in organizations (relational, transactional, and
balanced) and shows the process of their verbalization. The purpose
of the article is to present how the type of the psychological contract
relates to employee’s readiness to verbalize it. The article ends with
conclusions arising from the study.
Abstract: Inspired by the Formula-1 competition, IMechE
(Institute of Mechanical Engineers) and Formula SAE (Society of
Mechanical Engineers) organize annual competitions for University
and College students worldwide to compete with a single-seat racecar
they have designed and built. Design of the chassis or the frame is a
key component of the competition because the weight and stiffness
properties are directly related with the performance of the car and the
safety of the driver. In addition, a reduced weight of the chassis has
direct influence on the design of other components in the car. Among
others, it improves the power to weight ratio and the aerodynamic
performance. As the power output of the engine or the battery
installed in the car is limited to 80 kW, increasing the power to
weight ratio demands reduction of the weight of the chassis, which
represents the major part of the weight of the car. In order to reduce
the weight of the car, ION Racing team from University of
Stavanger, Norway, opted for a monocoque design. To ensure
fulfilment of the competition requirements of the chassis, the
monocoque design should provide sufficient torsional stiffness and
absorb the impact energy in case of possible collision. The study reported in this article is based on the requirements for
Formula Student competition. As part of this study, diverse
mechanical tests were conducted to determine the mechanical
properties and performances of the monocoque design. Upon a
comprehensive theoretical study of the mechanical properties of
sandwich composite materials and the requirements of monocoque
design in the competition rules, diverse tests were conducted
including 3-point bending test, perimeter shear test and test for
absorbed energy. The test panels were homemade and prepared with
equivalent size of the side impact zone of the monocoque, i.e. 275
mm x 500 mm, so that the obtained results from the tests can be
representative. Different layups of the test panels with identical core
material and the same number of layers of carbon fibre were tested
and compared. Influence of the core material thickness was also
studied. Furthermore, analytical calculations and numerical analysis
were conducted to check compliance to the stated rules for Structural
Equivalency with steel grade SAE/AISI 1010. The test results were
also compared with calculated results with respect to bending and
torsional stiffness, energy absorption, buckling, etc. The obtained results demonstrate that the material composition
and strength of the composite material selected for the monocoque
design has equivalent structural properties as a welded frame and thus
comply with the competition requirements. The developed analytical
calculation algorithms and relations will be useful for future
monocoque designs with different lay-ups and compositions.
Abstract: Rivers have transient storage or dead zones where
injected pollutants or solutes are entrapped for considerable period of
time, known as residence time, before being released into the main
flowing zones of rivers. In this study, a new empirical expression for
residence time, implementing genetic programming on published
dispersion data, has been derived. The proposed expression uses few
hydraulic and geometric characteristics of rivers which are normally
known to the authorities. When compared with some reported
expressions, based on various statistical indices, it can be concluded
that the proposed expression predicts the residence time of pollutants
in natural rivers more accurately.
Abstract: During the last decades, a number of food crises such
as Bovine Spongiform Encephalopathy (BSE), Mad-Cow disease,
Dioxin in chicken food, Food-and-Mouth Disease (FMD), have
certainly inflected the reliability of the food industry. Consequently,
the trend in applying different scientific methods of risk assessment
in food safety has obtained more attentions in the academic and
practice. However, lack of practical approach considering entire food
supply chain is tangible in the academic literature. In this regard, this
paper aims to apply risk assessment tool (FMEA) with integration of
Human Factor along the entire supply chain of food production and
test the method in a case study of Diary production, and analyze its
results.
Abstract: Strong anthropogenic impact has uncontrolled
consequences on the nature of the soil. Hence, up-to-date sustainable
methods of soil state improvement are essential. Investigators provide
the evidence that biochar can positively effects physical, chemical,
and biological soil properties and the abundance of mycorrhizal fungi
which are in the focus of this study. The main aim of the present
investigation is to demonstrate the effect of two types of plant growth
promoting bacteria (PGPB) inoculums along with the beech wood
biochar and mineral N additives on mycorrhizal colonization.
Experiment has been set up in laboratory conditions with containers
filled with arable soil from the protection zone of the main water
source “Brezova nad Svitavou”. Lactuca sativa (lettuce) has been
selected as a model plant. Based on the obtained data, it can be
concluded that mycorrhizal colonization increased as the result of
combined influence of biochar and PGPB inoculums amendment. In
addition, correlation analyses showed that the numbers of main
groups of cultivated bacteria were dependent on the degree of
mycorrhizal colonization.
Abstract: This paper aimed to introduce the solution of concrete
slump recovery using chemical admixture type-F (superplasticizer,
naphthalene base) to the practice in order to solve unusable concrete
problem due to concrete loss its slump, especially for those tropical
countries that have faster slump loss rate. In the other hand, randomly
adding superplasticizer into concrete can cause concrete to segregate.
Therefore, this paper also develops the estimation model used to
calculate amount of second dose of superplasticizer need for concrete
slump recovery. Fresh properties of ordinary Portland cement
concrete with volumetric ratio of paste to void between aggregate
(paste content) of 1.1-1.3 with water-cement ratio zone of 0.30 to
0.67 and initial superplasticizer (naphthalene base) of 0.25%-1.6%
were tested for initial slump and slump loss for every 30 minutes for
one and half hour by slump cone test. Those concretes with slump
loss range from 10% to 90% were re-dosed and successfully
recovered back to its initial slump. Slump after re-dosed was tested
by slump cone test. From the result, it has been concluded that, slump
loss was slower for those mix with high initial dose of
superplasticizer due to addition of superplasticizer will disturb
cement hydration. The required second dose of superplasticizer was
affected by two major parameters, which were water-cement ratio
and paste content, where lower water-cement ratio and paste content
cause an increase in require second dose of superplasticizer. The
amount of second dose of superplasticizer is higher as the solid
content within the system is increase, solid can be either from cement
particles or aggregate. The data was analyzed to form an equation use
to estimate the amount of second dosage requirement of
superplasticizer to recovery slump to its original.
Abstract: The main purpose of this study is to assess the
sediment quality and potential ecological risk in marine sediments in
Gymea Bay located in south Sydney, Australia. A total of 32 surface
sediment samples were collected from the bay. Current track
trajectories and velocities have also been measured in the bay. The
resultant trace elements were compared with the adverse biological
effect values Effect Range Low (ERL) and Effect Range Median
(ERM) classifications. The results indicate that the average values of
chromium, arsenic, copper, zinc, and lead in surface sediments all
reveal low pollution levels and are below ERL and ERM values. The
highest concentrations of trace elements were found close to
discharge points and in the inner bay, and were linked with high
percentages of clay minerals, pyrite and organic matter, which can
play a significant role in trapping and accumulating these elements.
The lowest concentrations of trace elements were found to be on the
shoreline of the bay, which contained high percentages of sand
fractions. It is postulated that the fine particles and trace elements are
disturbed by currents and tides, then transported and deposited in
deeper areas. The current track velocities recorded in Gymea Bay had
the capability to transport fine particles and trace element pollution
within the bay. As a result, hydrodynamic measurements were able to
provide useful information and to help explain the distribution of
sedimentary particles and geochemical properties. This may lead to
knowledge transfer to other bay systems, including those in remote
areas. These activities can be conducted at a low cost, and are
therefore also transferrable to developing countries. The advent of
portable instruments to measure trace elements in the field has also
contributed to the development of these lower cost and easily applied
methodologies available for use in remote locations and low-cost
economies.
Abstract: Escherichia coli (E. coli) is the most isolated bacteria
from blood circulation of septicemic calves. Given the prevalence of
septicemia in animals and its economic importance in veterinary
practice, better understanding of changes in clinical signs following
disease, may contribute to early detection of disorder. The present
study has been carried out to detect changes of clinical signs in
induced sepsis in calves with E. coli. Colisepticemia has been
induced in 10 twenty-day old healthy Holstein- Frisian calves with
intravenous injection of 1.5 X 109 colony forming units (cfu) of
O111:H8 strain of E. coli. Clinical signs including rectal temperature,
heart rate, respiratory rate, shock, appetite, sucking reflex, feces
consistency, general behavior, dehydration and standing ability were
recorded in experimental calves during 24 hours after induction of
colisepticemia. Blood culture was also carried out from calves four
times during experiment. ANOVA with repeated measure is used to
see changes of calves’ clinical signs to experimental colisepticemia,
and values of P≤ 0.05 was considered statistically significant. Mean
values of rectal temperature and heart rate as well as median values
of respiratory rate, appetite, suckling reflex, standing ability and feces
consistency of experimental calves increased significantly during
study (P 0.05). The
results of present study showed that total score of clinical signs in
calves with experimental colisepticemia increased significantly,
although score of some clinical signs such as shock did not change
significantly.
Abstract: To evaluate the effect of intramuscular administration
of vitamin A in pregnant dairy cows during late stages of pregnancy,
on vitamin A status of neonatal calves, a total of 30 cows were
randomly selected and divided into three groups; two treatment
groups and one control group. Single intramuscular injection of
2000000 IU vitamin A; was carried in 10 dairy cows at 7 months of
pregnancy (group 1). In second group of treated animals (10 cows)
the injection was performed in 8 months of pregnancy (group 2). Ten
pregnant dairy cows were received saline injection as placebo and
selected as control group. Blood samples were collected from
experimental dairy cows at 7 and 8 months of pregnancy as well as
their newborn calves’ pre and after colostrum intake. There was no
significant difference between vitamin A and β-carotene
concentration of dairy cows of three groups in two last months of
pregnancy (P> 0.05). Vitamin A concentration of calves of two
treatment groups before and after receiving of colostrum were
significantly higher than that in control group (P< 0.05). There was
no significant difference between serum concentrations of vitamin A
in calves of two treated groups (P> 0.05). β-Carotene concentration
of serum samples of dairy cows and neonatal calves of three groups
were not significantly different as compared with together. From
results of the present study it can be concluded that single injection of
vitamin A during at 7 or 8 month of pregnancy can significantly
increase level of vitamin A in their colostrum and neonatal calves.
Abstract: Large quantities of solid wastes being generated
worldwide from sources such as household, domestic, industrial,
commercial and construction demolition activities, leads to
environmental concerns. Utilization of these wastes in making
building construction materials can reduce the magnitude of the
associated problems. When these waste products are used in place of
other conventional materials, natural resources and energy are
preserved and expensive and/or potentially harmful waste disposal is
avoided. Recycling which is regarded as the third most preferred waste
disposal option, with its numerous environmental benefits, stand as a
viable option to offset the environmental impact associated with the
construction industry. This paper reviews the results of laboratory tests and important
research findings, and the potential of using these wastes in building
construction materials with focus on sustainable development.
Research gaps, which includes; the need to develop standard mix
design for solid waste based building materials; the need to develop
energy efficient method of processing solid waste use in concrete; the
need to study the actual behavior or performance of such building
materials in practical application and the limited real life application
of such building materials have also been identified. A research is being proposed to develop an environmentally
friendly, lightweight building block from recycled waste paper,
without the use of cement, and with properties suitable for use as
walling unit. This proposed research intends to incorporate,
laboratory experimentation and modeling to address the identified
research gaps.
Abstract: Microcantilevers are the basic MEMS devices, which
can be used as sensors, actuators and electronics can be easily built
into them. The detection principle of microcantilever sensors is based
on the measurement of change in cantilever deflection or change in its
resonance frequency. The objective of this work is to explore the
analogies between mechanical and electrical equivalent of
microcantilever beams. Normally scientists and engineers working in
MEMS use expensive software like CoventorWare, IntelliSuite,
ANSYS/Multiphysics etc. This paper indicates the need of developing
electrical equivalent of the MEMS structure and with that, one can
have a better insight on important parameters, and their interrelation of
the MEMS structure. In this work, considering the mechanical model
of microcantilever, equivalent electrical circuit is drawn and using
force-voltage analogy, it is analyzed with circuit simulation software.
By doing so, one can gain access to powerful set of intellectual tools
that have been developed for understanding electrical circuits Later
the analysis is performed using ANSYS/Multiphysics - software based
on finite element method (FEM). It is observed that both mechanical
and electrical domain results for a rectangular microcantlevers are in
agreement with each other.
Abstract: Geopolymer composites reinforced with flax fabrics
and nanoclay are fabricated and studied for physical and mechanical
properties using X-Ray Diffraction (XRD), Fourier Transform
Infrared Spectroscopy (FTIR), and Scanning Electron Microscope
(SEM). Nanoclay platelets at a weight of 1.0%, 2.0%, and 3.0% were
added to geopolymer pastes. Nanoclay at 2.0 wt.% was found to
improve density and decrease porosity while improving flexural
strength and post-peak toughness. A microstructural analysis
indicated that nanoclay behaves as filler and as an activator
supporting geopolymeric reaction while producing a higher content
geopolymer gel improving the microstructure of binders. The process
enhances adhesion between the geopolymer matrix and flax fibres.
Abstract: Both steady and unsteady turbulent mixed convection
heat transfer in a 3D lid-driven enclosure, which has constant heat
flux on the middle of bottom wall and with isothermal moving
sidewalls, is reported in this paper for working fluid with Prandtl
number Pr = 0.71. The other walls are adiabatic and stationary. The
dimensionless parameters used in this research are Reynolds number,
Re = 5000, 10000 and 15000, and Richardson number, Ri = 1 and 10.
The simulations have been done by using different turbulent methods
such as RANS, URANS, and LES. The effects of using different k-ε
models such as standard, RNG and Realizable k-ε model are
investigated. Interesting behaviours of the thermal and flow fields
with changing the Re or Ri numbers are observed. Isotherm and
turbulent kinetic energy distributions and variation of local Nusselt
number at the hot bottom wall are studied as well. The local Nusselt
number is found increasing with increasing either Re or Ri number.
In addition, the turbulent kinetic energy is discernibly affected by
increasing Re number. Moreover, the LES results have shown good
ability of this method in predicting more detailed flow structures in
the cavity.
Abstract: In this study, the effects and interactions of reaction
time and capping agent assistance during sol-gel synthesis of
magnesium substituted hydroxyapatite nanopowder (MgHA) on
hydroxyapatite (HA) to β-tricalcium phosphate (β-TCP) ratio, Ca/P
ratio and mean crystallite size was examined experimentally as well
as through statistical analysis. MgHA nanopowders were synthesized
by sol-gel technique at room temperature using aqueous solution of
calcium nitrate tetrahydrate, magnesium nitrate hexahydrate and
potassium dihydrogen phosphate as starting materials. The reaction
time for sol-gel synthesis was varied between 15 to 60 minutes. Two
process routes were followed with and without addition of
triethanolamine (TEA) in the solutions. The elemental compositions
of as-synthesized powders were determined using X-ray fluorescence
(XRF) spectroscopy. The functional groups present in the assynthesized
MgHA nanopowders were established through Fourier
Transform Infrared Spectroscopy (FTIR). The amounts of phases
present, Ca/P ratio and mean crystallite sizes of MgHA nanopowders
were determined using X-ray diffraction (XRD). The HA content in
biphasic mixture of HA and β-TCP and Ca/P ratio in as-synthesized
MgHA nanopowders increased effectively with reaction time of sols
(p0.15, two way ANOVA). The MgHA nanopowders
synthesized with TEA assistance exhibited 14 nm lower crystallite
size (p
Abstract: One of the global combinatorial optimization
problems in machine learning is feature selection. It concerned with
removing the irrelevant, noisy, and redundant data, along with
keeping the original meaning of the original data. Attribute reduction
in rough set theory is an important feature selection method. Since
attribute reduction is an NP-hard problem, it is necessary to
investigate fast and effective approximate algorithms. In this paper,
we proposed two feature selection mechanisms based on memetic
algorithms (MAs) which combine the genetic algorithm with a fuzzy
record to record travel algorithm and a fuzzy controlled great deluge
algorithm, to identify a good balance between local search and
genetic search. In order to verify the proposed approaches, numerical
experiments are carried out on thirteen datasets. The results show that
the MAs approaches are efficient in solving attribute reduction
problems when compared with other meta-heuristic approaches.
Abstract: Response Surface Methods (RSM) provide
statistically validated predictive models that can then be manipulated
for finding optimal process configurations. Variation transmitted to
responses from poorly controlled process factors can be accounted
for by the mathematical technique of propagation of error (POE),
which facilitates ‘finding the flats’ on the surfaces generated by
RSM. The dual response approach to RSM captures the standard
deviation of the output as well as the average. It accounts for
unknown sources of variation. Dual response plus propagation of
error (POE) provides a more useful model of overall response
variation. In our case, we implemented this technique in predicting
compressive strength of concrete of 28 days in age. Since 28 days is
quite time consuming, while it is important to ensure the quality
control process. This paper investigates the potential of using design
of experiments (DOE-RSM) to predict the compressive strength of
concrete at 28th day. Data used for this study was carried out from
experiment schemes at university of Benghazi, civil engineering
department. A total of 114 sets of data were implemented. ACI mix
design method was utilized for the mix design. No admixtures were
used, only the main concrete mix constituents such as cement, coarseaggregate,
fine aggregate and water were utilized in all mixes.
Different mix proportions of the ingredients and different water
cement ratio were used. The proposed mathematical models are
capable of predicting the required concrete compressive strength of
concrete from early ages.
Abstract: This study evaluated the acute toxicity and tissue
distribution of intravenously administered gold nanoparticles
(AuNPs) in male rabbits. Rabbits were exposed to single dose of
AuNPs (300 μg/ kg). Toxic effects were assessed via general
behavior, hematological parameters, serum biochemical parameters,
and histopathological examination of various rabbits’ organs.
Inductively coupled plasma–mass spectrometry (ICP-MS) was used
to determine gold concentrations in tissue samples collected at
predetermined time intervals. After one week, AuNPs exerted no
obvious acute toxicity in rabbits. However, inflammatory reactions
were observed in liver, lungs and kidneys accompanied with mild
absolute neutrophilia and significant monocytosis. The highest gold
levels were found in the spleen and liver followed by lungs, and
kidneys. These results indicated that AuNPs could be distributed
extensively to various tissues in the body, but primarily in the spleen
and liver.
Abstract: The aim of this paper is to propose a general
framework for storing, analyzing, and extracting knowledge from
two-dimensional echocardiographic images, color Doppler images,
non-medical images, and general data sets. A number of high
performance data mining algorithms have been used to carry out this
task. Our framework encompasses four layers namely physical
storage, object identification, knowledge discovery, user level.
Techniques such as active contour model to identify the cardiac
chambers, pixel classification to segment the color Doppler echo
image, universal model for image retrieval, Bayesian method for
classification, parallel algorithms for image segmentation, etc., were
employed. Using the feature vector database that have been
efficiently constructed, one can perform various data mining tasks
like clustering, classification, etc. with efficient algorithms along
with image mining given a query image. All these facilities are
included in the framework that is supported by state-of-the-art user
interface (UI). The algorithms were tested with actual patient data
and Coral image database and the results show that their performance
is better than the results reported already.