Abstract: Excavation and retaining walls are of challenging
issues in civil engineering. In this study, the behavior of one
important type of supporting systems called Contiguous Bored Pile
(CBP) retaining wall is investigated using a physical model. Besides,
a comparison is made between two modes of free end piles (soft bed)
and fixed end piles (stiff bed). Also a back calculation of effective
length (the real free length of pile) is done by measuring lateral
deflection of piles in different stages of excavation in both
aforementioned cases. Based on observed results, for the fixed end
mode, the effective length to free length ratio (Leff/L0) is equal to
unity in initial stages of excavation and less than 1 in its final stages
in a decreasing manner. While this ratio for free end mode, remains
constant during all stages of excavation and is always less than unity.
Abstract: This paper presents the application of the Discrete
Component Model for heating and evaporation to multi-component
biodiesel fuel droplets in direct injection internal combustion engines.
This model takes into account the effects of temperature gradient,
recirculation and species diffusion inside droplets. A distinctive
feature of the model used in the analysis is that it is based on the
analytical solutions to the temperature and species diffusion
equations inside the droplets. Nineteen types of biodiesel fuels are
considered. It is shown that a simplistic model, based on the
approximation of biodiesel fuel by a single component or ignoring
the diffusion of components of biodiesel fuel, leads to noticeable
errors in predicted droplet evaporation time and time evolution of
droplet surface temperature and radius.
Abstract: Nanocrystalline powders of the lead-free piezoelectric
material, tantalum-substituted potassium sodium niobate
(K0.5Na0.5)(Nb0.9Ta0.1)O3 (KNNT), were produced using a Retsch
PM100 planetary ball mill by setting the milling time to 15h, 20h,
25h, 30h, 35h and 40h, at a fixed speed of 250rpm. The average
particle size of the milled powders was found to decrease from 12nm
to 3nm as the milling time increases from 15h to 25h, which is in
agreement with the existing theoretical model. An anomalous
increase to 98nm and then a drop to 3nm in the particle size were
observed as the milling time further increases to 30h and 40h
respectively. Various sizes of these starting KNNT powders were
used to investigate the effect of milling time on the microstructure,
dielectric properties, phase transitions and piezoelectric properties of
the resulting KNNT ceramics. The particle size of starting KNNT
was somewhat proportional to the grain size. As the milling time
increases from 15h to 25h, the resulting ceramics exhibit
enhancement in the values of relative density from 94.8% to 95.8%,
room temperature dielectric constant (εRT) from 878 to 1213, and
piezoelectric charge coefficient (d33) from 108pC/N to 128pC/N. For
this range of ceramic samples, grain size refinement suppresses the
maximum dielectric constant (εmax), shifts the Curie temperature (Tc)
to a lower temperature and the orthorhombic-tetragonal phase
transition (Tot) to a higher temperature. Further increase of milling
time from 25h to 40h produces a gradual degradation in the values of
relative density, εRT, and d33 of the resulting ceramics.
Abstract: Social media continues to grow, and user interfaces
may become more appealing if cultural characteristics are
incorporated into their design.
Facebook was designed in the west, and the original language was
English. Subsequently, the words in the user interface were translated
to other languages, including Arabic.
Arabic words are written from right to left, and English is written
from left to right. The translated version may misrepresent the
original design and users’ preferences may be influenced by their
culture, which should be considered in the user interface design.
Previous research indicates that users are more comfortable when
interacting with a user interface, which relates to their own culture.
Therefore, this paper, using a survey, investigates the preferences of
Saudi Arabians on the Arabic version of the user interface of
Facebook.
Abstract: The main purpose of this work was verify the
influence of the accelerated carbonation in the physical and
mechanical properties of the hybrid composites, reinforced with
micro and nanofibers and composites with microfibers. The
composites were produced by the slurry vacuum dewatering method,
followed by pressing. It was produced using two formulations: 8% of
eucalyptus pulp + 1% of the nanofibrillated cellulose and 9% of
eucalyptus pulp, both were subjected to accelerated carbonation. The
results showed that the accelerated carbonation contributed to
improve the physical and mechanical properties of the hybrid
composites and of the composites reinforced with microfibers
(eucalyptus pulp).
Abstract: Adapting quickly to environmental dynamism is
essential for an organization to develop outsourcing strategic and
management in order to sustain competitive advantage. This research
used the Partial Least Squares Structural Equation Modeling (PLSSEM)
tool to investigate the factors of environmental dynamism
impact on the strategic outsourcing success among electrical and
electronic manufacturing industries in outsourcing management.
Statistical results confirm that the inclusion of customer demand,
technological change, and competition level as a new combination
concept of environmental dynamism, has positive effects on
outsourcing success. Additionally, this research demonstrates the
acceptability of PLS-SEM as a statistical analysis to furnish a better
understanding of environmental dynamism in outsourcing
management in Malaysia. A practical finding contributes to
academics and practitioners in the field of outsourcing management.
Abstract: We model and simulate the combined effect of fiber
dispersion and frequency chirp of a directly modulated high-speed
laser diode on the figures of merit of a non-amplified 40-Gbps optical
fiber link. We consider both the return to zero (RZ) and non-return to
zero (NRZ) patterns of the pseudorandom modulation bits. The
performance of the fiber communication system is assessed by the
fiber-length limitation due to the fiber dispersion. We study the
influence of replacing standard single-mode fibers by non-zero
dispersion-shifted fibers on the maximum fiber length and evaluate
the associated power penalty. We introduce new dispersion
tolerances for 1-dB power penalty of the RZ and NRZ 40-Gbps
optical fiber links.
Abstract: This study presents a cost-effective approach for rapid
fabricating modeling platforms utilized in fused deposition modeling
system. A small-batch production of modeling platforms about 20
pieces can be obtained economically through silicone rubber mold
using vacuum casting without applying the plastic injection molding.
The air venting systems is crucial for fabricating modeling platform
using vacuum casting. Modeling platforms fabricated can be used for
building rapid prototyping model after sandblasting. This study offers
industrial value because it has both time-effectiveness and
cost-effectiveness.
Abstract: Floods play a key role in landform evolution of an
area. This process is likely to alter the topography of the earth’s
surface. The present study area, Kota Bharu is very prone to floods
extends from upstream of Kelantan River near Kemubu to the
downstream area near Kuala Besar. These flood events which occur
every year in the study area exhibit a strong bearing on river
morphological set-up. In the present study, three satellite imageries of
different time periods have been used to manifest the post-flood
landform changes. The pre-processing of the images such as subset,
geometric corrections and atmospheric corrections were carried-out
using ENVI 4.5 followed by the analysis processes. Twenty sets of
cross sections were plotted using software Erdas 9.2, ERDAS and
ArcGis 10 for the all three images. The results show a significant
change in the length of the cross section which suggest that the
geomorphological processes play a key role in carving and shaping
the river banks during the floods.
Abstract: Today’s modern interconnected power system is
highly complex in nature. In this, one of the most important
requirements during the operation of the electric power system is the
reliability and security. Power and frequency oscillation damping
mechanism improve the reliability. Because of power system
stabilizer (PSS) low speed response against of major fault such as
three phase short circuit, FACTs devise that can control the network
condition in very fast time, are becoming popular. But FACTs
capability can be seen in a major fault present when nonlinear models
of FACTs devise and power system equipment are applied. To realize
this aim, the model of multi-machine power system with FACTs
controller is developed in MATLAB/SIMULINK using Sim Power
System (SPS) blockiest. Among the FACTs device, Static
synchronous series compensator (SSSC) due to high speed changes
its reactance characteristic inductive to capacitive, is effective power
flow controller. Tuning process of controller parameter can be
performed using different method. But Genetic Algorithm (GA)
ability tends to use it in controller parameter tuning process. In this
paper firstly POD controller is used to power oscillation damping.
But in this station, frequency oscillation dos not has proper damping
situation. So FOD controller that is tuned using GA is using that
cause to damp out frequency oscillation properly and power
oscillation damping has suitable situation.
Abstract: Using cold EGR method with variable venturi and
turbocharger has a very significant effect on reduction of NOX and
grime simultaneously. EGR cooler is one of the most important parts
in the cold EGR circuit. In this paper optimum design of cooler for
working in different percentages of EGR and for determining
optimum temperature of exhausted gases, growth of efficiency,
reduction of weight, dimension, expenditures, sediment and also
optimum performance by using gasoil which has significant amounts
of brimstone are investigated and optimized.
Abstract: The extermination and proper disposal of
pharmaceutical wastes from expired and unused medications remains
a disputable issue due to their specific nature and characteristics.
Even though the hazards from these wastes are already well known in
terms of environment and human health, people still treat them as
usual wastes. At a national level, in many countries the management
of pharmaceutical and medical wastes has been one of the main
objectives in order to protect people’s health and the environment.
Even though many legal regulations exist in this respect, there has not
been a single law that would clearly explain the procedures of
returning medicines, ways of selection, treatment and extermination
of pharmaceutical wastes. This paper aims at analyzing the practices
of pharmaceutical waste management and treatment in some
European countries as well as a review of the legislation and official
guidelines in managing these kinds of wastes and protecting the
environment and human health. A suitable treatment and
management of expired medications and other similar wastes would
be in the interest of public health in the first place, as well as in the
interest of healthcare institutions and other bodies engaged in
environment protection.
Abstract: This paper proposes a backward/forward sweep
method to analyze the power flow in radial distribution systems. The
distribution system has radial structure and high R/X ratios. So the
newton-raphson and fast decoupled methods are failed with
distribution system. The proposed method presents a load flow study
using backward/forward sweep method, which is one of the most
effective methods for the load-flow analysis of the radial distribution
system. By using this method, power losses for each bus branch and
voltage magnitudes for each bus node are determined. This method
has been tested on IEEE 33-bus radial distribution system and
effective results are obtained using MATLAB.
Abstract: Corrosion inhibitors are widely used in concrete
industry to reduce the corrosion rate of steel rebar which is present in
contact with aggressive environments. The present work aims to
using Zamzam water from well located within the Masjid al-Haram
in Mecca, Saudi Arabia 20 m (66 ft) east of the Kaaba, the holiest
place in Islam as corrosion inhibitor for steel in rain water and
simulated acid rain. The effect of Zamzam water was investigated by
electrochemical impedance spectroscopy (EIS) and Potentiodynamic
polarization techniques in Department of Civil Engineering - IUT
Saint-Nazaire, Nantes University, France. Zamzam water is
considered to be one of the most important steel corrosion inhibitor
which is frequently used in different industrial applications. Results
showed that zamzam water gave a very good inhibition for steel
corrosion in rain water and simulated acid rain.
Abstract: The in-cylinder flow and mixture formations are
significant in view of today’s increasing concern on environmental
issues and stringent emission regulations. In this paper, the numerical
simulations of a SI engine at different engine speeds (2000-5000
rpm) at fixed intake flow pressure of 1 bar are studied using the AVL
FIRE software. The simulation results show that when the engine
speed at fixed intake flow pressure is increased, the volumetric
efficiency of the engine decreases. This is due to a richer fuel
conditions near the engine cylinder wall when engine speed is
increased. Significant effects of impingement are also noted on the
upper and side walls of the engine cylinder. These variations in
mixture formation before ignition could affect the thermodynamics
efficiency and specific fuel consumption that would lead to a reduced
engine performance.
Abstract: Learner motivation is considered to be an important
component for the Blended e-Learning (BL) Method. BL is an
effective learning method in multiple domains, which opens several
opportunities for its participants to engage in the learning
environment. This research explores the learners’ perspective of BL
according to the Self-Determination Theory (SDT). It identifies the
opportunities and challenges for using the BL in Logistics Education
(LE) in Egyptian Higher Education (HE). SDT is approached from
different perspectives within the relationship between Intrinsic
Motivation (IM), Extrinsic Motivation (EM) and Amotivation (AM).
A self-administered face-to-face questionnaire was used to collect
data from learners who were geographically widely spread around
three colleges of International Transport and Logistics (CILTs) at the
Arab Academy for Science, Technology and Maritime Transport
(AAST&MT) in Egypt. Six hundred and sixteen undergraduates
responded to a questionnaire survey. Respondents were drawn from
three branches in Greater Cairo, Alexandria, and Port Said. The data
analysis used was SPSS 22 and AMOS 18.
Abstract: In this paper, a coupled damage effect in the
instability of a composite rotor is presented, under dynamic loading
response in the harmonic analysis condition. The analysis of the
stress which operates the rotor is done. Calculations of different
energies and the virtual work of the aerodynamic loads from the rotor
blade are developed. The use of the composite material for the rotor
offers a good stability.
Numerical calculations on the model developed prove that the
damage effect has a negative effect on the stability of the rotor.
The study of the composite rotor in transient system allowed
determining the vibratory responses due to various excitations.
Abstract: Soil erosion is a very complex phenomenon, resulting
from detachment and transport of soil particles by erosion agents.
The kinetic energy of raindrop is the energy available for detachment
and transport by splashing rain. The soil erodibility is defined as the
ability of soil to resist to erosion. For this purpose, an experimental
study was conducted in the laboratory using rainfall simulator to
study the effect of the kinetic energy of rain (Ec) on the soil
erodibility (K). The soil used was a sandy agricultural soil of 62.08%
coarse sand, 19.14% fine sand, 6.39% fine silt, 5.18% coarse silt and
7.21% clay. The obtained results show that the kinetic energy of
raindrops evolves as a power law with soil erodibility.
Abstract: The financial crises caused a collapse in prices of
most asset classes, raising the attention on alternative investments
such as sukuk, a smaller, fast growing but often misunderstood
market. We study diversification benefits of sukuk, their correlation
with other asset classes and the effects of their inclusion in
investment portfolios of institutional and retail investors, through a
comprehensive comparison of their risk/return profiles during and
after the financial crisis.
We find a beneficial performance adjusted for the specific
volatility together with a lower correlation especially during the
financial crisis. The distribution of sukuk returns is positively skewed
and leptokurtic, with a risk/return profile similarly to high yield
bonds. Overall, our results suggest that sukuk present diversification
opportunities, a significant volatility-adjusted performance and lower
correlations especially during the financial crisis.
Our findings are relevant for a number of institutional investors.
Long term investors, such as life insurers would benefit from sukuk’s
protective features during financial crisis yet keeping return and
growth opportunities, whereas banks would gain due to their role of
placers, advisors, market makers or underwriters.
Abstract: This paper reviews the internal use of blogs and their
potential effectiveness as organisational learning tools. Since the
emergence of the concept of ‘Enterprise 2.0’ there remains a lack of
empirical evidence associated with how organisations are applying
social media tools and whether they are effective towards supporting
organisational learning. Surprisingly, blogs, one of the more
traditional social media tools, still remains under-researched in the
context of ‘Enterprise 2.0’ and organisational learning. The aim of
this paper is to identify the theoretical linkage between blogs and
organisational learning in addition to reviewing prior research on
organisational blogging exploring why this area remains underresearched.
Through a literature review, one of the principal findings
of this paper is that organisational blogs have a mutual compatibility
with the interpretivist aspect of organisational learning. This paper
further advocates that further empirical work in this subject area is
required to substantiate this theoretical assumption.