Abstract: In the present study we have investigated axial
buckling characteristics of nanocomposite beams reinforced by
single-walled carbon nanotubes (SWCNTs). Various types of beam
theories including Euler-Bernoulli beam theory, Timoshenko beam
theory and Reddy beam theory were used to analyze the buckling
behavior of carbon nanotube-reinforced composite beams.
Generalized differential quadrature (GDQ) method was utilized to
discretize the governing differential equations along with four
commonly used boundary conditions. The material properties of the
nanocomposite beams were obtained using molecular dynamic (MD)
simulation corresponding to both short-(10,10) SWCNT and long-
(10,10) SWCNT composites which were embedded by amorphous
polyethylene matrix. Then the results obtained directly from MD
simulations were matched with those calculated by the mixture rule
to extract appropriate values of carbon nanotube efficiency
parameters accounting for the scale-dependent material properties.
The selected numerical results were presented to indicate the
influences of nanotube volume fractions and end supports on the
critical axial buckling loads of nanocomposite beams relevant to
long- and short-nanotube composites.
Abstract: This paper reports on the response of a fiber-optic
sensing probe to small concentrations of hydrogen peroxide (H2O2)
vapor at room temperature. H2O2 has extensive applications in industrial and medical
environments. Conversely, H2O2 can be a health hazard by itself. For
example, H2O2 induces cellular damage in human cells and its
presence can be used to diagnose illnesses such as asthma and human
breast cancer. Hence, development of reliable H2O2 sensor is of vital
importance to detect and measure this species. Ferric ferrocyanide, referred to as Prussian Blue (PB), was
deposited on the tip of a multimode optical fiber through the single
source precursor technique and served as an indicator of H2O2 in a
spectroscopic manner. Sensing tests were performed in H2O2-H2O
vapor mixtures with different concentrations of H2O2. The results of sensing tests show the sensor is able to detect H2O2
concentrations in the range of 50.6 ppm to 229.5 ppm. Furthermore,
the sensor response to H2O2 concentrations is linear in a log-log scale
with the adjacent R-square of 0.93. This sensing behavior allows us
to detect and quantify the concentration of H2O2 in the vapor phase.
Abstract: Istanbul-Karakoy Port, field of this study, has lost its
former significance in time due to the transformation of urban
functions. Today, activities for regeneration of this region continue in
two forms and scales. First of these activities is the "planned
transformation projects," which also includes “Galataport project”,
and the second one is "spontaneous transformation," which consists
of individual interventions. Galataport project that based on the idea
of arranging the area specifically for tourists was prepared in 2005
and became a topic of tremendous public debate. On the other hand,
the "spontaneous transformation" that is observed in Karakoy District
starts in 2004 with the foundation of “Istanbul Modern Museum”
which allowed the cultural integration of old naval warehouses of the
port to the daily life. Following this adaptive reuse intervention, the
district started to accommodate numerous art galleries, studios, caféworkshops
and design stores. In this context, this paper first examines
regeneration studies in obsolete port regions, analyzes the planned
and ongoing socio-spatial transformations in the specific case of
Karakoy and performs a critical review of the sustainability of the
proposals on how to reinstate the district in the active life of Istanbul.
Abstract: Social Avoidance is one of the most important
problems that face a good number of disabled students. It results from
the negative attitudes of non-disabled students, teachers and others.
Some of the past research has shown that non-disabled individuals
hold negative attitudes toward persons with disabilities. The present
study aims to alleviate Social Avoidance by applying the Cognitive
Behavioral Intervention. 24 Blind students aged 19–24 (university students) were randomly
chosen we compared an experimental group (consisted of 12
students) who went through the intervention program, with a control
group (12 students also) who did not go through such intervention.
We used the Social Avoidance and Distress Scale (SADS) to assess
social anxiety and distress behavior. The author used many
techniques of cognitive behavioral intervention such as modeling,
cognitive restructuring, extension, contingency contracts, selfmonitoring,
assertiveness training, role play, encouragement and
others. Statistically, T-test was employed to test the research
hypothesis. Result showed that there is a significance difference between the
experimental group and the control group after the intervention and
also at the follow up stages of the Social Avoidance and Distress
Scale. Also for the experimental group, there is a significance
difference before the intervention and the follow up stages for the
scale. Results showed that, there is a decrease in social avoidance.
Accordingly, cognitive behavioral intervention program was
successful in decreasing social avoidance for blind students.
Abstract: The purpose of this study is to identify human walking vertical force by using FFT power spectrum density from the experimental acceleration data of the human body. An experiment on human walking is carried out on a stationary floor especially paying attention to higher components of dynamic vertical walking force. Based on measured acceleration data of the human lumbar part, not only in-phase component with frequency of 2fw, 3fw, but also in-opposite-phase component with frequency of 0.5 fw, 1.5 fw, 2.5 fw where fw is the walking rate is observed. The vertical vibration of pedestrian bridge induced by higher components of human walking vertical force is also discussed in this paper. A full scale measurement for the existing pedestrian bridge with center span length of 33 m is carried out focusing on the resonance phenomenon due to higher components of human walking vertical force. Dynamic response characteristics excited by these vertical higher components of human walking are revealed from the dynamic design viewpoint of pedestrian bridge.
Abstract: The world crude oil demand is projected to rise to 108.5 million bbl/d by the year 2035. With reserves estimated at 869 billion tonnes worldwide, coal remains an abundant resource. The aim of this work was to produce a high value hydrocarbon liquid product using a Direct Coal Liquefaction (DCL) process at, relatively mild operating conditions. Via hydrogenation, the temperature-staged approach was investigated in a dual reactor lab-scale pilot plant facility. The objectives included maximising thermal dissolution of the coal in the presence of tetralin as the hydrogen donor solvent in the first stage with 2:1 and 3:1 solvent: coal ratios. Subsequently, in the second stage, hydrogen saturation, in particular, hydrodesulphurization (HDS) performance was assessed. Two commercial hydrotreating catalysts were investigated viz. NickelMolybdenum (Ni-Mo) and Cobalt-Molybdenum (Co-Mo). GC-MS results identified 77 compounds and various functional groups present in the first and second stage liquid product. In the first stage 3:1 ratios and liquid product yields catalysed by magnetite were favoured. The second stage product distribution showed an increase in the BTX (Benzene, Toluene, Xylene) quality of the liquid product, branched chain alkanes and a reduction in the sulphur concentration. As an HDS performer and selectivity to the production of long and branched chain alkanes, Ni-Mo had an improved performance over Co-Mo. Co-Mo is selective to a higher concentration of cyclohexane. For 16 days on stream each, Ni-Mo had a higher activity than Co-Mo. The potential to cover the demand for low–sulphur, crude diesel and solvents from the production of high value hydrocarbon liquid in the said process, is thus demonstrated.
Abstract: In the past few years, high consumption of soft drinks
has attracted negative attention world-wide due to its possible
adverse effects, leading the health conscious people to find
alternative nutraceutical or herbal health drinks. In the present study,
a nutraceutical soft drink was developed utilizing some easily
available and well known traditional herbs having nutritional
potential. The key ingredients were selected as bael, amla, lemon
juice, ashwagandha and poppy seeds based on their household routine
use in the summer with proven refreshing, cooling and energetic
feeling since ages. After several trials made, the final composition of
nutraceutical summer soft drink was selected as most suitable
combination based on the taste, physicochemical, microbial and
organoleptic point of view. The physicochemical analysis of the
prepared drink found to contain optimum level of titratable acidity,
total soluble solids and pH which were in accordance of the
commercial recommendations. There were no bacterial colonies
found in the product therefore found within limits. During the nine
point’s hedonic scale sensory evaluation, the drink was strongly liked
for colour, taste, flavour and texture. The formulation was found to
contain flavonoids (80mg/100ml), phenolics (103mg/100ml), vitamin
C (250mg/100ml) and has antioxidant potential (75.52%) apart from
providing several other essential vitamins, minerals and healthy
components. The developed nutraceutical drink provides an
economical and feasible option for the consumers with very good
taste combined with potential health benefits. The present drink is
potentially capable to replace the synthetic soft drinks available in the
market.
Abstract: A novel Active Flap System (AFS) has been developed
at DTU Wind Energy, as a result of a 3-year R&D project following
almost 10 years of innovative research in this field. The full scale AFS
comprises an active deformable trailing edge has been tested at the
unique rotating test facility at the Risø Campus of DTU Wind Energy
in Denmark. The design and instrumentation of the wing section and
the AFS are described. The general description and objectives of the
rotating test rig at the Risø campus of DTU are presented, along
with an overview of sensors on the setup and the test cases. The
post-processing of data is discussed and results of steady, flap step
and azimuth control flap cases are presented.
Abstract: The purpose of this paper is to examine the effects and
relationship of stress and social support towards the quality of life
among flood victims in Malaysia. A total of 764 respondents took
part in the survey via convenience sampling. The Depression,
Anxiety and Stress scale (DASS) was utilized to measure stress while
The Multidimensional Scale of Perceived Social Support was used to
measure social support. To measure quality of life, the combination
of WHO Quality of Life – BREF (WHOQOL-BREF) and The Impact
of Event Scale – Revised (IES-R) were utilized. The findings of this
study indicate that there were significant correlations between
variables in the study. The findings showed a significant negative
relation between stress and quality of life; and significant positive
correlations between support from family as well as support from
friends with quality of life. Stress and support from family were
found to be significant predictors that influence the quality of life
among flood victims.
Abstract: Review of studies carried out on the use of bagasse
ash for the improvement of deficient soils in Nigeria, with emphasis
on lateritic and black cotton soils is presented. Although, the bagasse
ash is mostly used as additive to the conventional soil stabilizers
(cement and lime), the studies generally showed improvement in the
geotechnical properties of the soils, either modified or stabilized with
the ash. This showed the potentials of using this agricultural waste
(bagasse ash) in the improvement of geotechnical properties of
deficient soils, thus suggesting that using this material at large scale
level in geotechnical engineering practice could help in the provision
of stable and durable structures, reduce cost of soil improvement and
also reduces environmental nuisance caused by the unused waste in
Nigeria.
Abstract: Due to the interference effects, the intrinsic
aerodynamic parameters obtained from the individual component
testing are always fundamentally different than those obtained for
complete model testing. Consideration and limitation for such testing
need to be taken into account in any design work related to the
component buildup method. In this paper, the scaled model of a
straight rectangular canard of a hybrid buoyant aircraft is tested at 50
m/s in IIUM-LSWT (Low Speed Wind Tunnel). Model and its
attachment with the balance are kept rigid to have results free from
the aeroelastic distortion. Based on the velocity profile of the test
section’s floor; the height of the model is kept equal to the
corresponding boundary layer displacement. Balance measurements
provide valuable but limited information of overall aerodynamic
behavior of the model. Zero lift coefficient is obtained at -2.2o and
the corresponding drag coefficient was found to be less than that at
zero angle of attack. As a part of the validation of low fidelity tool,
plot of lift coefficient plot was verified by the experimental data and
except the value of zero lift coefficients, the overall trend has under
predicted the lift coefficient. Based on this comparative study, a
correction factor of 1.36 is proposed for lift curve slope obtained
from the panel method.
Abstract: To decrease the grating scale thermal expansion error,
a novel method which based on multiple temperature detection is
proposed. Several temperature sensors are installed on the grating
scale and the temperatures of these sensors are recorded. The
temperatures of every point on the grating scale are calculated by
interpolating between adjacent sensors. According to the thermal
expansion principle, the grating scale thermal expansion error model
can be established by doing the integral for the variations of position
and temperature. A novel compensation method is proposed in this
paper. By applying the established error model, the grating scale
thermal expansion error is decreased by 90% compared with no
compensation. The residual positioning error of the grating scale is
less than 15μm/10m and the accuracy of the machine tool is
significant improved.
Abstract: Wire Electric Discharge Machining (WEDM) is
thermal machining process capable of machining very hard
electrically conductive material irrespective of their hardness.
WEDM is being widely used to machine micro scale parts with the
high dimensional accuracy and surface finish. The objective of this
paper is to optimize the process parameters of wire EDM to fabricate
the micro channels and to calculate the surface finish and material
removal rate of micro channels fabricated using wire EDM. The
material used is aluminum 6061 alloy. The experiments were
performed using CNC wire cut electric discharge machine. The effect
of various parameters of WEDM like pulse on time (TON) with the
levels (100, 150, 200), pulse off time (TOFF) with the levels (25, 35,
45) and current (IP) with the levels (105, 110, 115) were investigated
to study the effect on output parameter i.e. Surface Roughness and
Material Removal Rate (MRR). Each experiment was conducted
under different conditions of pulse on time, pulse off time and peak
current. For material removal rate, TON and Ip
were the most significant process parameter. MRR increases with the increase in
TON and Ip and decreases with the increase in TOFF. For surface
roughness, TON and Ip have the maximum effect and TOFF was found
out to be less effective.
Abstract: The Japanese version of the SF-36 has been employed
to assess individuals’ health-related QOL (HRQOL). This study aimed
to clarify the HRQOL of motorists with a spinal cord injury, in order to
compare these individuals' SF-36 scores and national standard values.
A total of 100 motorists with a spinal cord injury participated in this
study. Participants’ HRQOL was evaluated using the Japanese version
of the SF-36 (second edition). The score for each subscale was
standardized based on data on the Japanese population. The average
scores for NPF, NRP, NBP, NGH, NVT, NSF, NRE, and NMH were
10.9, 41.8, 45.9, 47.1, 46.1, 46.7, 46.0, and 47.4 points, respectively.
Subjects showed significantly lower scores for NPF and NRP
compared with national standard values, which were both ≤ 45.0
points, but relatively normal scores for the other items: NBP, NGH,
NVT, NSF, NRE and NMH (> 45.0 points). The average scores for
PCS, MCS and RCS were 21.9, 56.0, and 50.0 points, respectively.
Subjects showed a significantly lower PCS score (≤ 20.0 points);
however, the MCS score was higher (> 55.0 points) along with a
relatively normal RCS score in these individuals (= 50.0 points).
Abstract: This paper presents the interface ConductHome which
controls home automation systems with a Leap Motion using
“invariant gesture protocols”. This interface is meant to simplify the
interaction of the user with its environment. A hardware part allows
the Leap Motion to be carried around the house. A software part
interacts with the home automation box and displays the useful
information for the user. An objective of this work is the
development of a natural/invariant/simple gesture control interface to
help elder people/people with disabilities.
Abstract: This paper seeks to assess the implications of bank
consolidation on lending, which largely determine the survival and
performance of small and medium scale enterprises and in turn the
development of the Nigerian economy. Ordinary least square
technique, correlation matrix test and Granger –causality test were
employed to measure the extent to which lending to small and
medium scale enterprises were influenced. The result showed that
bank deposit (BD) impacted on lending to small and medium scale
enterprises. Commercial and merchant bank lending rate had
statistically insignificant effect on the dependent variable. There is a
shift of focus by commercial banks from small and medium scale
enterprises (small customers) to major investors (big customers).
While micro finance banks work hard at providing funds to small and
medium scale entrepreneurs, their capacity to meet the needs of these
entrepreneurs is constrained. The capital and deposits of micro
finance bank should be boosted in order to effectively support small
and medium scale enterprises through loans.
Abstract: Elliptic curve discrete logarithm problem(ECDLP) is
one of problems on which the security of pairing-based cryptography
is based. This paper considers Pollard’s rho method to evaluate
the security of ECDLP on Barreto-Naehrig(BN) curve that is an
efficient pairing-friendly curve. Some techniques are proposed to
make the rho method efficient. Especially, the group structure on
BN curve, distinguished point method, and Montgomery trick are
well-known techniques. This paper applies these techniques and
shows its optimization. According to the experimental results for
which a large-scale parallel system with MySQL is applied, 94-bit
ECDLP was solved about 28 hours by parallelizing 71 computers.
Abstract: This paper investigates the thermal issue of permanent
magnet synchronous generator which is frequently used in direct
drive gearless small-scale wind turbine applications. Permanent
Magnet Synchronous Generator (PMSG) is designed with 2.5 kW
continuous and 6 kW peak power. Then considering generator
geometry, mechanical design of wind turbine is performed. Thermal
analysis and optimization is carried out considering all wind turbine
components to reach realistic results. This issue is extremely
important in research and development (R&D) process for wind
turbine applications.
Abstract: This study presents a hybrid metaheuristic algorithm
to obtain optimum designs for steel space buildings. The optimum
design problem of three-dimensional steel frames is mathematically
formulated according to provisions of LRFD-AISC (Load and
Resistance factor design of American Institute of Steel Construction).
Design constraints such as the strength requirements of structural
members, the displacement limitations, the inter-story drift and the
other structural constraints are derived from LRFD-AISC
specification. In this study, a hybrid algorithm by using teachinglearning
based optimization (TLBO) and harmony search (HS)
algorithms is employed to solve the stated optimum design problem.
These algorithms are two of the recent additions to metaheuristic
techniques of numerical optimization and have been an efficient tool
for solving discrete programming problems. Using these two
algorithms in collaboration creates a more powerful tool and
mitigates each other’s weaknesses. To demonstrate the powerful
performance of presented hybrid algorithm, the optimum design of a
large scale steel building is presented and the results are compared to
the previously obtained results available in the literature.
Abstract: In this paper, we study the optical nonlinearities of
Silver sulfide (Ag2S) nanostructures dispersed in the Dimethyl
sulfoxide (DMSO) under exposure to 532 nm, 15 nanosecond (ns)
pulsed laser irradiation. Ultraviolet–visible absorption spectrometry
(UV-Vis), X-ray diffraction (XRD), and transmission electron
microscopy (TEM) are used to characterize the obtained nanocrystal
samples. The band gap energy of colloid is determined by analyzing
the UV–Vis absorption spectra of the Ag2S NPs using the band
theory of semiconductors. Z-scan technique is used to characterize
the optical nonlinear properties of the Ag2S nanoparticles (NPs).
Large enhancement of two photon absorption effect is observed with
increase in concentration of the Ag2S nanoparticles using open Zscan
measurements in the ns laser regime. The values of the nonlinear
absorption coefficients are determined based on the local nonlinear
responses including two photon absorption. The observed aperture
dependence of the Ag2S NP limiting performance indicates that the
nonlinear scattering plays an important role in the limiting action of
the sample. The concentration dependence of the optical liming is
also investigated. Our results demonstrate that the optical limiting
threshold decreases with increasing the silver sulfide NPs in DMSO.