Abstract: In this research the effects of adding silica and
alumina nanoparticles on flow ability and compressive strength of
cementitious composites based on Portland cement were investigated.
In the first stage, the rheological behavior of different samples
containing nanosilica, nanoalumina and polypropylene, polyvinyl
alcohol and polyethylene fibers were evaluated. With increasing of
nanoparticles in fresh samples, the slump flow diameter reduced.
Fibers reduced the flow ability of the samples and viscosity
increased. With increasing of the micro silica particles to cement
ratio from 2/1 to 2/2, the slump flow diameter increased. By adding
silica and alumina nanoparticles up to 3% and 2% respectively, the
compressive strength increased and after decreased. Samples
containing silica nanoparticles and fibers had the highest compressive
strength.
Abstract: A novel hybrid model of the lumbar spine, allowing
fast static and dynamic simulations of the disc pressure
and the spine mobility, is introduced in this work. Our
contribution is to combine rigid bodies, deformable finite
elements, articular constraints, and springs into a unique model
of the spine. Each vertebra is represented by a rigid body
controlling a surface mesh to model contacts on the facet
joints and the spinous process. The discs are modeled using
a heterogeneous tetrahedral finite element model. The facet
joints are represented as elastic joints with six degrees of
freedom, while the ligaments are modeled using non-linear
one-dimensional elastic elements. The challenge we tackle
is to make these different models efficiently interact while
respecting the principles of Anatomy and Mechanics.
The mobility, the intradiscal pressure, the facet joint force and
the instantaneous center of rotation of the lumbar spine are
validated against the experimental and theoretical results of
the literature on flexion, extension, lateral bending as well as
axial rotation.
Our hybrid model greatly simplifies the modeling task and
dramatically accelerates the simulation of pressure within the
discs, as well as the evaluation of the range of motion and the
instantaneous centers of rotation, without penalizing precision.
These results suggest that for some types of biomechanical
simulations, simplified models allow far easier modeling and
faster simulations compared to usual full-FEM approaches
without any loss of accuracy.
Abstract: A collection of thirty cultivars/clones of a red pitaya
was used to investigate flowering response to lighting
supplementation in the winter season of 2013-2014 in southern
Taiwan. The night-breaking treatment was conducted during the
period of 10 Oct. 2013 to 5 Mar. 2014 with 4-continuous hours
(22.00 – 02.00 hrs) of additional lighting daily using incandescent
bulbs (100W). Among cultivars and clones tested, twenty-three
genotypes, most belonging to the red-magenta flesh type, were found
to have positively flowering response to the lighting treatment. The
duration of night-breaking treatment for successful flowering
initiation varied from 33- 48 days. The lighting-sensitive genotypes
bore 1-2 flowering flushes. Floral and fruiting stages took 21-26 and
46-59 days, respectively. Among sixteen fruiting genotypes, the
highest fruit set rates were found in Damao 9, D4, D13, Chaozou
large, Chaozhou 5, Small Nick and F22. Five cultivars and clones
(Orejona, D4, Chaozhou large, Chaozhou 5 and Small Nick) produced
fruits with an average weight of more than 300 g per fruit which were
higher than those of the fruits formed in the summer of 2013. Fruits
produced during off-season containing total soluble solids (TSS)
from 17.5 to 20.7oBrix, which were higher than those produced inseason.
Abstract: The present paper summarizes the analysis of the
request for consultation of information and data on industrial
emissions made publicly available on the web site of the Ministry of
Environment, Land and Sea on integrated pollution prevention and
control from large industrial installations, the so called “AIA Portal”.
As a matter of fact, a huge amount of information on national
industrial plants is already available on internet, although it is usually
proposed as textual documentation or images.
Thus, it is not possible to access all the relevant information
through interoperability systems and also to retrieval relevant
information for decision making purposes as well as rising of
awareness on environmental issue.
Moreover, since in Italy the number of institutional and private
subjects involved in the management of the public information on
industrial emissions is substantial, the access to the information is
provided on internet web sites according to different criteria; thus, at
present it is not structurally homogeneous and comparable.
To overcome the mentioned difficulties in the case of the
Coordinating Committee for the implementation of the Agreement
for the industrial area in Taranto and Statte, operating before the
IPPC permit granting procedures of the relevant installation located
in the area, a big effort was devoted to elaborate and to validate data
and information on characterization of soil, ground water aquifer and
coastal sea at disposal of different subjects to derive a global
perspective for decision making purposes. Thus, the present paper
also focuses on main outcomes matured during such experience.
Abstract: An analysis is carried out to investigate the effect of
magnetic field and heat source on the steady boundary layer flow and
heat transfer of a Casson nanofluid over a vertical cylinder stretching
exponentially along its radial direction. Using a similarity
transformation, the governing mathematical equations, with the
boundary conditions are reduced to a system of coupled, non –linear
ordinary differential equations. The resulting system is solved
numerically by the fourth order Runge – Kutta scheme with shooting
technique. The influence of various physical parameters such as
Reynolds number, Prandtl number, magnetic field, Brownian motion
parameter, thermophoresis parameter, Lewis number and the natural
convection parameter are presented graphically and discussed for non
– dimensional velocity, temperature and nanoparticle volume
fraction. Numerical data for the skin – friction coefficient, local
Nusselt number and the local Sherwood number have been tabulated
for various parametric conditions. It is found that the local Nusselt
number is a decreasing function of Brownian motion parameter Nb
and the thermophoresis parameter Nt.
Abstract: In this paper we describe one critical research
program within a complex, ongoing multi-year project (2010 to 2014
inclusive) with the overall goal to improve the learning outcomes for
first year undergraduate commerce/business students within an
Information Systems (IS) subject with very large enrolment. The
single research program described in this paper is the analysis of
student attitudes and decision making in relation to the availability of
formative assessment feedback via Web-based real time conferencing
and document exchange software (Adobe Connect). The formative
assessment feedback between teaching staff and students is in respect
of an authentic problem-based, team-completed assignment. The
analysis of student attitudes and decision making is investigated via
both qualitative (firstly) and quantitative (secondly) application of the
Theory of Planned Behavior (TPB) with a two statistically-significant
and separate trial samples of the enrolled students. The initial
qualitative TPB investigation revealed that perceived self-efficacy,
improved time-management, and lecturer-student relationship
building were the major factors in shaping an overall favorable
student attitude to online feedback, whilst some students expressed
valid concerns with perceived control limitations identified within the
online feedback protocols. The subsequent quantitative TPB
investigation then confirmed that attitude towards usage, subjective
norms surrounding usage, and perceived behavioral control of usage
were all significant in shaping student intention to use the online
feedback protocol, with these three variables explaining 63 percent of
the variance in the behavioral intention to use the online feedback
protocol. The identification in this research of perceived behavioral
control as a significant determinant in student usage of a specific
technology component within a virtual learning environment (VLE)
suggests that VLEs could now be viewed not as a single, atomic
entity, but as a spectrum of technology offerings ranging from the
mature and simple (e.g., email, Web downloads) to the cutting-edge
and challenging (e.g., Web conferencing and real-time document
exchange). That is, that all VLEs should not be considered the same.
The results of this research suggest that tertiary students have the
technological sophistication to assess a VLE in this more selective
manner.
Abstract: This study is concerned with the optimization of
fermentation parameters for the hyper production of mannanase from
Fusarium oxysporum SS-25 employing two step statistical strategy
and kinetic characterization of crude enzyme preparation. The
Plackett-Burman design used to screen out the important factors in
the culture medium revealed 20% (w/w) wheat bran, 2% (w/w) each
of potato peels, soyabean meal and malt extract, 1% tryptone, 0.14%
NH4SO4, 0.2% KH2PO4, 0.0002% ZnSO4, 0.0005% FeSO4, 0.01%
MnSO4, 0.012% SDS, 0.03% NH4Cl, 0.1% NaNO3 in brewer’s spent
grain based medium with 50% moisture content, inoculated with
2.8×107 spores and incubated at 30oC for 6 days to be the main
parameters influencing the enzyme production. Of these factors, four
variables including soyabean meal, FeSO4, MnSO4 and NaNO3 were
chosen to study the interactive effects and their optimum levels in
central composite design of response surface methodology with the
final mannanase yield of 193 IU/gds. The kinetic characterization
revealed the crude enzyme to be active over broader temperature and
pH range. This could result in 26.6% reduction in kappa number with
4.93% higher tear index and 1% increase in brightness when used to
treat the wheat straw based kraft pulp. The hydrolytic potential of
enzyme was also demonstrated on both locust bean gum and guar
gum.
Abstract: The progress of industry integrated circuits in recent
years has been pushed by continuous miniaturization of transistors.
With the reduction of dimensions of components at 0.1 micron and
below, new physical effects come into play as the standard simulators
of two dimensions (2D) do not consider. In fact the third dimension
comes into play because the transverse and longitudinal dimensions
of the components are of the same order of magnitude. To describe
the operation of such components with greater fidelity, we must
refine simulation tools and adapted to take into account these
phenomena. After an analytical study of the static characteristics of
the component, according to the different operating modes, a
numerical simulation is performed of field-effect transistor with
submicron gate MESFET GaInP. The influence of the dimensions of
the gate length is studied. The results are used to determine the
optimal geometric and physical parameters of the component for their
specific applications and uses.
Abstract: Advanced head and neck cancers are aggressive
tumours, which require aggressive treatment. Treatment efficiency is
often hindered by cancer cell repopulation during radiotherapy,
which is due to various mechanisms triggered by the loss of tumour
cells and involves both stem and differentiated cells. The aim of the
current paper is to present in silico simulations of radiotherapy
schedules on a virtual head and neck tumour grown with biologically
realistic kinetic parameters. Using the linear quadratic formalism of
cell survival after radiotherapy, altered fractionation schedules
employing various treatment breaks for normal tissue recovery are
simulated and repopulation mechanism implemented in order to
evaluate the impact of various cancer cell contribution on tumour
behaviour during irradiation. The model has shown that the timing of
treatment breaks is an important factor influencing tumour control in
rapidly proliferating tissues such as squamous cell carcinomas of the
head and neck. Furthermore, not only stem cells but also
differentiated cells, via the mechanism of abortive division, can
contribute to malignant cell repopulation during treatment.
Abstract: This study attempts to elicit the perceptions and
attitudes of EFL learners of the Preparatory Year Program at KSU
towards dialogue journal writing as an EFL learning strategy. The
descriptive research design used incorporated both qualitative and
quantitative instruments to accomplish the objectives of the study. A
learners’ attitude questionnaire and follow-up interviewswith learners
from a randomly selected representative sample of the participants
were employed. The participants were 55 female Saudi university
students in the Preparatory Year Program at King Saud University.
The analysis of the results indicated that the PYP learners had highly
positive attitudes towards dialogue journal writing in their EFL
classes and positive perceptions of the benefits of the use of dialogue
journal writing as an EFL learning strategy. The results also revealed
that dialogue journals are considered an effective EFL learning
strategy since they fulfill various needs for both learners and
instructors. Interestingly, the analysis of the results also revealed that
Saudi university level students tend to write about personal topics in
their dialogue journals more than academic ones.
Abstract: Polysulfone (PSU) is a specialty engineering polymer
having various industrial applications. PSU is especially used in
waste water treatment membranes due to its good mechanical
properties, structural and chemical stability. But it is a hydrophobic
material and therefore its surface aim to pollute easily. In order to
resolve this problem and extend the properties of membrane, PSU
surface is rendered hydrophilic by addition of the sepiolite
nanofibers. Sepiolite is one of the natural clays, which is a hydrate
magnesium silicate fiber, also one of the well known layered clays of
the montmorillonites where has several unique channels and pores
within. It has also moisture durability, strength and low price.
Sepiolite channels give great capacity of absorption and good surface
properties. In this study, nanocomposites of commercial PSU and
Sepiolite were prepared by solvent mixing method. Different organic
solvents and their mixtures were used. Rheological characteristics of
PSU-Sepiolite solvent mixtures were analyzed, the solubility of
nanocomposite content in those mixtures were studied.
Abstract: The design and plantwide control of an integrated
plant where the endothermic 1,4-butanediol dehydrogenation and the
exothermic furfural hydrogenation is simultaneously performed in a
single reactor is studied. The reactions can be carried out in an
adiabatic reactor using small hydrogen excess and with reduced
parameter sensitivity. The plant is robust and flexible enough to
allow different production rates of γ-butyrolactone and 2-methyl
furan, keeping high product purities. Rigorous steady state and
dynamic simulations performed in AspenPlus and AspenDynamics to
support the conclusions.
Abstract: Malaysia is rich with historic buildings, particularly in
Penang and Malacca states. Restoration activities are increasingly
important as these states are recognized under UNESCO World
Heritage Sites. Restoration activities help to maintain the uniqueness
and value of a heritage building. However, increasing in restoration
activities has resulted in large quantities of waste. To cope with this
problem, the 3R concept (reduce, reuse and recycle) is introduced.
The 3R concept is one of the waste management hierarchies. This
concept is still yet to apply in the building restoration industry
compared to the construction industry. Therefore, this study aims to
promote the 3R concept in the heritage building restoration industry.
This study aims to examine the importance of 3R concept and to
identify challenges in applying the 3R concept in the heritage
building restoration industry. This study focused on contractors and
consultants who are involved in heritage restoration projects in
Penang. Literature review and interviews helps to reach the research
objective. Data that obtained is analyzed by using content analysis.
For the research, application of 3R concept is important to conserve
natural resources and reduce pollution problems. However, limited
space to organise waste is the obstruction during the implementation
of this concept. In conclusion, the 3R concept plays an important role
in promoting environmental conservation and helping in reducing the
construction waste.
Abstract: Managing and improving efficiency in the current
highly competitive global automotive industry demands that those
companies adopt leaner and more flexible systems. During the past
20 years the domestic automotive industry in North America has been
focusing on establishing new management strategies in order to meet
market demands. The lean management process also known as
Toyota Manufacturing Process (TPS) or lean manufacturing
encompasses tools and techniques that were established in order to
provide the best quality product with the fastest lead time at the
lowest cost. The following paper presents a study that focused on
improving labor efficiency at one of the Big Three (Ford, GM,
Chrysler LLC) domestic automotive facility in North America. The
objective of the study was to utilize several lean management tools in
order to optimize the efficiency and utilization levels at the “Pre-
Marriage” chassis area in a truck manufacturing and assembly
facility. Utilizing three different lean tools (i.e. Standardization of
work, 7 Wastes, and 5S) this research was able to improve efficiency
by 51%, utilization by 246%, and reduce operations by 14%. The
return on investment calculated based on the improvements made
was 284%.
Abstract: Eucalyptus species are well reputed for their
traditional use in Asia as well as in other parts of the world; therefore,
the present study was designed to investigate the antimicrobial and
antioxidant activities associated with essential oils from different
Eucalyptus species. Essential oils from the leaves of six Eucalyptus
species, including: Eucalyptus woodwardi, Eucalyptus stricklandii,
Eucalyptus salubris, Eucalyptus sargentii, Eucalyptus torquata and
Eucalyptus wandoo were separated by hydrodistillation and dried
over anhydrous sodium sulphate. DPPH, ferric reducing antioxidant
power, and hydroxyl radical scavenging activity assays were carried
out to evaluate the antioxidant potential of the oils. The results
indicate that examined oils exhibit substantial antioxidant activities
relative to ascorbic acid. Previously, these oils were evaluated for
their antimicrobial activities, against wide range of bacterial and
fungal strains, and they were shown to possess significant
antimicrobial activities. In this study, further investigation into the
growth kinetics of oil-treated microbial cultures was conducted. The
results clearly demonstrate that the microbial growth was markedly
inhibited when treated with sub-MIC concentrations of the oils.
Taken together, the results obtained indicate a high potential of the
examined essential oils as bioactive oils, for nutraceutical and
medical applications, possessing significant antioxidant and anti
microbial activities.
Abstract: This paper presents modeling of an Alternating
Current (AC) Photovoltaic (PV) module using Matlab/Simulink. The
proposed AC-PV module model is simple, realistic, and application
oriented. The model is derived on module level as compared to cell
level directly from the information provided by the manufacturer data
sheet. DC-PV module, MPPT control, BC, VSI and LC filter, all
were treated as a single unit. The model accounts for changes in
variations of both irradiance and temperature. The AC-PV module
proposed model is simulated and the results are compared with the
datasheet projected numbers to validate model’s accuracy and
effectiveness. Implementation and results demonstrate simplicity and
accuracy, as well as reliability of the model.
Abstract: In this paper, a nonlinear Finite Element Analysis
(FEA) was carried out using ANSYS software to build a model able
of predicting the behavior of Reinforced Concrete (RC) beams with
unbonded reinforcement. The FEA model was compared to existing
experimental data by other researchers. The existing experimental
data consisted of 16 beams that varied from structurally sound beams
to beams with unbonded reinforcement with different unbonded
lengths and reinforcement ratios. The model was able to predict the
ultimate flexural strength, load-deflection curve, and crack pattern of
concrete beams with unbonded reinforcement. It was concluded that
when the when the unbonded length is less than 45% of the span,
there will be no decrease in the ultimate flexural strength due to the
loss of bond between the steel reinforcement and the surrounding
concrete regardless of the reinforcement ratio. Moreover, when the
reinforcement ratio is relatively low, there will be no decrease in
ultimate flexural strength regardless of the length of unbond.
Abstract: Vegetation affects the mean and turbulent flow
structure. It may increase flood risks and sediment transport.
Therefore, it is important to develop analytical approaches for the bed
shear stress on vegetated bed, to predict resistance caused by
vegetation. In the recent years, experimental and numerical models
have both been developed to model the effects of submerged
vegetation on open-channel flow. In this paper, different analytic
models are compared and tested using the criteria of deviation, to
explore their capacity for predicting the mean velocity and select the
suitable one that will be applied in real case of rivers. The
comparison between the measured data in vegetated flume and
simulated mean velocities indicated, a good performance, in the case
of rigid vegetation, whereas, Huthoff model shows the best
agreement with a high coefficient of determination (R2=80%) and the
smallest error in the prediction of the average velocities.
Abstract: A Motzkin shift is a mathematical model for constraints
on genetic sequences. In terms of the theory of symbolic dynamics,
the Motzkin shift is nonsofic, and therefore, we cannot use the Perron-
Frobenius theory to calculate its topological entropy. The Motzkin
shift M(M,N) which comes from language theory, is defined to be the
shift system over an alphabet A that consists of N negative symbols,
N positive symbols and M neutral symbols. For an x in the full shift,
x will be in the Motzkin subshift M(M,N) if and only if every finite
block appearing in x has a non-zero reduced form. Therefore, the
constraint for x cannot be bounded in length. K. Inoue has shown that
the entropy of the Motzkin shift M(M,N) is log(M + N + 1). In this
paper, a new direct method of calculating the topological entropy of
the Motzkin shift is given without any measure theoretical discussion.
Abstract: This research study aimed to survey and analyze the
attitudes of pre-service teachers’ the analytical thinking development
based on Miller’s Model. The informants of this study were 22 third
year teacher students majoring in Thai. The course where the
instruction was conducted was English for Academic Purposes in
Thai Language 2. The instrument of this research was an open-ended
questionnaire with two dimensions of questions: academic and
satisfaction dimensions. The investigation revealed the positive
attitudes. In the academic dimension, the majority of 12 (54.54%),
the highest percentage, reflected that the method of teaching
analytical thinking and language simultaneously was their new
knowledge and the similar percentage also belonged to text cohesion
in writing. For the satisfaction, the highest frequency count was from
17 of them (77.27%) and this majority favored the openness or
friendliness of the teacher.