Abstract: Aluminium matrix composites with alumina
reinforcements give superior mechanical & physical properties. Their
applications in several fields like automobile, aerospace, defense,
sports, electronics, bio-medical and other industrial purposes are
becoming essential for the last several decades. In the present work,
fabrication of hybrid composite was done by Stir casting technique
using Al 6061 as a matrix with alumina and silicon carbide (SiC) as
reinforcement materials. The weight percentage of alumina is varied
from 2 to 4% and the silicon carbide weight percentage is maintained
constant at 2%. Hardness and wear tests are performed in the as cast
and heat treated conditions. Age hardening treatment was performed
on the specimen with solutionizing at 550°C, aging at two
temperatures (150 and 200°C) for different time durations. Hardness
distribution curves are drawn and peak hardness values are recorded.
Hardness increase was very sensitive with respect to the decrease in
aging temperature. There was an improvement in wear resistance of
the peak aged material when aged at lower temperature. Also
increase in weight percent of alumina, increases wear resistance at
lower temperature but opposite behavior was seen when aged at
higher temperature.
Abstract: This paper addresses a cutting edge method of
business demand forecasting, based on an empirical probability
function when the historical behavior of the data is random.
Additionally, it presents error determination based on the numerical
method technique ‘propagation of errors.’ The methodology was
conducted characterization and process diagnostics demand planning
as part of the production management, then new ways to predict its
value through techniques of probability and to calculate their mistake
investigated, it was tools used numerical methods. All this based on
the behavior of the data. This analysis was determined considering
the specific business circumstances of a company in the sector of
communications, located in the city of Bogota, Colombia. In
conclusion, using this application it was possible to obtain the
adequate stock of the products required by the company to provide its
services, helping the company reduce its service time, increase the
client satisfaction rate, reduce stock which has not been in rotation
for a long time, code its inventory, and plan reorder points for the
replenishment of stock.
Abstract: This study examines the feasibility of indirect solar
desalination in oil producing countries in the Middle East and North
Africa (MENA) region. It relies on value engineering (VE) and costbenefit
with sensitivity analyses to identify optimal coupling
configurations of desalination and solar energy technologies. A
comparative return on investment was assessed as a function of water
costs for varied plant capacities (25,000 to 75,000 m3/day), project
lifetimes (15 to 25 years), and discount rates (5 to 15%) taking into
consideration water and energy subsidies, land cost as well as
environmental externalities in the form of carbon credit related to
greenhouse gas (GHG) emissions reduction. The results showed
reverse osmosis (RO) coupled with photovoltaic technologies (PVs)
as the most promising configuration, robust across different prices for
Brent oil, discount rates, as well as different project lifetimes.
Environmental externalities and subsidies analysis revealed that a
16% reduction in existing subsidy on water tariffs would ensure
economic viability. Additionally, while land costs affect investment
attractiveness, the viability of RO coupled with PV remains possible
for a land purchase cost
Abstract: This study is aiming at establishing the relationship
between the optical signal of flame and an equivalent ratio of flame. In
this experiment, flame optical signal in a furnace is measured using
photodiode. The combustion system is composed of metal fiber burner
and vertical furnace, and flame chemiluminescence is measured at
various experimental conditions. In this study, the flame
chemiluminescence of laminar premixed flame is measured using
commercially available photodiode. It is experimentally investigated
the relationship between equivalent ratio and photodiode signal. In
addition, the strategy of combustion control method is proposed using
the optical signal and fuel pressure.
The results showed that certain relationship between optical data of
photodiode and equivalence ratio exists, and this leads to the
successful application of this system for instantaneous measurement of
equivalence ration of the combustion system.
Abstract: When neck pain is associated with pain, numbness, or
weakness in the arm, shoulder, or hand, further investigation is
needed as these are symptoms indicating pressure on one or more
nerve roots. Evaluation necessitates a neurologic examination and
imaging using an MRI/CT scan. A degenerating disc loses some
thickness and is less flexible, causing inter-vertebrae space to narrow.
A radiologist diagnoses an Intervertebral Disc Degeneration (IDD) by
localizing every inter-vertebral disc and identifying the pathology in
a disc based on its geometry and appearance. Accurate localizing is
necessary to diagnose IDD pathology. But, the underlying image
signal is ambiguous: a disc’s intensity overlaps the spinal nerve
fibres. Even the structure changes from case to case, with possible
spinal column bending (scoliosis). The inter-vertebral disc
pathology’s quantitative assessment needs accurate localization of the
cervical region discs. In this work, the efficacy of multilevel set
segmentation model, to segment cervical discs is investigated. The
segmented images are annotated using a simple distance matrix.
Abstract: Bringing forth a survey on recent higher order spline
techniques for solving boundary value problems in ordinary
differential equations. Here we have discussed the summary of the
articles since 2000 till date based on higher order splines like Septic,
Octic, Nonic, Tenth, Eleventh, Twelfth and Thirteenth Degree
splines. Comparisons of methods with own critical comments as
remarks have been included.
Abstract: Steady three-dimensional and two free surface waves
generated by moving bodies are presented, the flow problem to be
simulated is rich in complexity and poses many modeling challenges
because of the existence of breaking waves around the ship hull, and
because of the interaction of the two-phase flow with the turbulent
boundary layer. The results of several simulations are reported. The
first study was performed for NACA0012 of hydrofoil with different
meshes, this section is analyzed at h/c= 1, 0345 for 2D. In the second
simulation a mathematically defined Wigley hull form is used to
investigate the application of a commercial CFD code in prediction of
the total resistance and its components from tangential and normal
forces on the hull wetted surface. The computed resistance and wave
profiles are used to estimate the coefficient of the total resistance for
Wigley hull advancing in calm water under steady conditions. The
commercial CFD software FLUENT version 12 is used for the
computations in the present study. The calculated grid is established
using the code computer GAMBIT 2.3.26. The shear stress k-ωSST
model is used for turbulence modeling and the volume of fluid
technique is employed to simulate the free-surface motion. The
second order upwind scheme is used for discretizing the convection
terms in the momentum transport equations, the Modified HRIC
scheme for VOF discretization. The results obtained compare well
with the experimental data.
Abstract: A compound parabolic concentrator (CPC) is a wellknown
non-imaging concentrator that will concentrate the solar
radiation onto receiver (PV cell). One of disadvantage of CPC is has
tall and narrow height compared to its diameter entry aperture area.
Therefore, for economic reason, a truncation had been done by
removed from the top of the full height CPC. This also will lead to
the decreases of concentration ratio but it will be negligible. In this
paper, the flux distribution of untruncated and truncated 2-D hollow
compound parabolic trough concentrator (hCPTC) design is
presented. The untruncated design has initial height H=193.4mm
with concentration ratio C_(2-D)=4. This paper presents the optical
simulation of compound parabolic trough concentrator using raytracing
software TracePro. Results showed that, after the truncation,
the height of CPC reduced 45% from initial height with the
geometrical concentration ratio only decrease 10%. Thus, the cost of
reflector and material dielectric usage can be saved especially at
manufacturing site.
Abstract: The Economic Lot Scheduling Problem (ELSP) is a
valuable mathematical model that can support decision-makers to
make scheduling decisions. The basic period approach is effective for
solving the ELSP. The assumption for applying the basic period
approach is that a product must use its maximum production rate to be
produced. However, a product can lower its production rate to reduce
the average total cost when a facility has extra idle time. The past
researches discussed how a product adjusts its production rate under
the common cycle approach. To the best of our knowledge, no studies
have addressed how a product lowers its production rate under the
basic period approach. This research is the first paper to discuss this
topic. The research develops a simple fixed rate approach that adjusts
the production rate of a product under the basic period approach to
solve the ELSP. Our numerical example shows our approach can find a
better solution than the traditional basic period approach. Our
mathematical model that applies the fixed rate approach under the
basic period approach can serve as a reference for other related
researches.
Abstract: Nowadays, the main goal for modern horticultural
production is an increase the quality. In recent years, the use of
organic fertilizers or biostimulants that can be applied in agriculture
to improve quali-quantitative crop yields has encountered increasing
interest. Biostimulants are gaining importance also for their possible
use in organic and sustainable agriculture, to avoid excessive
fertilizer applications. Consecutive experimental trials were carried
out in the Apulia region (southern Italy) on three herbaceous crops
(cauliflower, pepper, fennel) grown in pots under conventional and
organic fertilization systems without and with biostimulants. The aim
was to determine the effects of three biostimulants (Siapton®10L,
Micotech L, Lysodin Alga-Fert) on quali-quantitative yield
characteristics. At harvest, the quali-quantitative yield characteristics
of each crop were determined. All of the experimental data were
subjected to analysis of variance (ANOVA), and when significant
effects were detected, the means were compared using Tukey’s tests.
These data show large differences in these yield characteristics
between conventional and organic crops, particularly highlighting
higher yields for the conventional crops, while variable results were
generally observed when the biostimulants were applied. In this
context, there were no effects of the biostimulants on the quantitative
yield, whereas there were low positive effects on the qualitative
characteristics, as related to higher dry matter content of cauliflower,
and higher soluble solids content of pepper. Moreover, there were
evident positive effects of the biostimulants with fennel, due to the
lower nitrate content. These latter data are in line with most of the
published literature obtained for other herbaceous crops.
Abstract: Fast speed drives for Permanent Magnet Synchronous
Motor (PMSM) is a crucial performance for the electric traction
systems. In this paper, PMSM is derived with a Model-based
Predictive Control (MPC) technique. Fast speed tracking is achieved
through optimization of the DC source utilization using MPC. The
technique is based on predicting the optimum voltage vector applied
to the driver. Control technique is investigated by comparing to the
cascaded PI control based on Space Vector Pulse Width Modulation
(SVPWM). MPC and SVPWM-based FOC are implemented with the
TMS320F2812 DSP and its power driver circuits. The designed MPC
for a PMSM drive is experimentally validated on a laboratory test
bench. The performances are compared with those obtained by a
conventional PI-based system in order to highlight the improvements,
especially regarding speed tracking response.
Abstract: The novel 3D SnO cabbages self-assembled by
nanosheets were successfully synthesized via template-free
hydrothermal growth method under facile conditions. The XRD
results manifest that the as-prepared SnO is tetragonal phase. The
TEM and HRTEM results show that the cabbage nanosheets are
polycrystalline structure consisted of considerable single-crystalline
nanoparticles. Two typical Raman modes A1g=210 and Eg=112 cm-1
of SnO are observed by Raman spectroscopy. Moreover, galvanostatic
cycling tests has been performed using the SnO cabbages as anode
material of lithium ion battery and the electrochemical results suggest
that the synthesized SnO cabbage structures are a promising anode
material for lithium ion batteries.
Abstract: The nanoindentation behaviour and phase
transformation of annealed single-crystal silicon wafers are examined.
The silicon specimens are annealed at temperatures of 250, 350 and
450ºC, respectively, for 15 minutes and are then indented to maximum
loads of 30, 50 and 70 mN. The phase changes induced in the indented
specimens are observed using transmission electron microscopy
(TEM) and micro-Raman scattering spectroscopy (RSS). For all
annealing temperatures, an elbow feature is observed in the unloading
curve following indentation to a maximum load of 30 mN. Under
higher loads of 50 mN and 70 mN, respectively, the elbow feature is
replaced by a pop-out event. The elbow feature reveals a complete
amorphous phase transformation within the indented zone, whereas
the pop-out event indicates the formation of Si XII and Si III phases.
The experimental results show that the formation of these crystalline
silicon phases increases with an increasing annealing temperature and
indentation load. The hardness and Young’s modulus both decrease as
the annealing temperature and indentation load are increased.
Abstract: Total Quality Management (TQM) is a managerial
approach that improves the competitiveness of the industry,
meanwhile Information technology (IT) was introduced with TQM
for handling the technical issues which is supported by quality
experts for fulfilling the customers’ requirement. Present paper aims
to utilise AHP (Analytic Hierarchy Process) methodology to
priorities and rank the hierarchy levels of TQM enablers and IT
resource together for its successful implementation in the Information
and Communication Technology (ICT) industry. A total of 17 TQM
enablers (nine) and IT resources (eight) were identified and
partitioned into 3 categories and were prioritised by AHP approach.
The finding indicates that the 17 sub-criteria can be grouped into
three main categories namely organizing, tools and techniques, and
culture and people. Further, out of 17 sub-criteria, three sub-criteria:
top management commitment and support, total employee
involvement, and continuous improvement got highest priority
whereas three sub-criteria such as structural equation modelling,
culture change, and customer satisfaction got lowest priority. The
result suggests a hierarchy model for ICT industry to prioritise the
enablers and resources as well as to improve the TQM and IT
performance in the ICT industry. This paper has some managerial
implication which suggests the managers of ICT industry to
implement TQM and IT together in their organizations to get
maximum benefits and how to utilize available resources. At the end,
conclusions, limitation, future scope of the study are presented.
Abstract: The system for analyzing and eliciting public
grievances serves its main purpose to receive and process all sorts of
complaints from the public and respond to users. Due to the more
number of complaint data becomes big data which is difficult to store
and process. The proposed system uses HDFS to store the big data
and uses MapReduce to process the big data. The concept of cache
was applied in the system to provide immediate response and timely
action using big data analytics. Cache enabled big data increases the
response time of the system. The unstructured data provided by the
users are efficiently handled through map reduce algorithm. The
processing of complaints takes place in the order of the hierarchy of
the authority. The drawbacks of the traditional database system used
in the existing system are set forth by our system by using Cache
enabled Hadoop Distributed File System. MapReduce framework
codes have the possible to leak the sensitive data through
computation process. We propose a system that add noise to the
output of the reduce phase to avoid signaling the presence of
sensitive data. If the complaints are not processed in the ample time,
then automatically it is forwarded to the higher authority. Hence it
ensures assurance in processing. A copy of the filed complaint is sent
as a digitally signed PDF document to the user mail id which serves
as a proof. The system report serves to be an essential data while
making important decisions based on legislation.
Abstract: Because blueberries are worldwide recognized as a
good source of beneficial components, their consumption has
increased in the past decades, and so have the scientific works about
their properties. Hence, this work was undertaken to evaluate the
effect of some production and conservation factors on the properties
of blueberries from cultivar Bluecrop. The physical and chemical
analyses were done according to established methodologies and then
all data was treated using software SPSS for assessment of the
possible differences among the factors investigated and/or the
correlations between the variables at study. The results showed that
location of production influenced some of the berries properties
(caliber, sugars, antioxidant activity, color and texture) and that the
age of the bushes was correlated with moisture, sugars and acidity, as
well as lightness. On the other hand, altitude of the farm only was
correlated to sugar content. With regards to conservation, it
influenced only anthocyanins content and DPPH antioxidant activity.
Finally, the type of extract and the order of extraction had a
pronounced influence on all the phenolic properties evaluated.
Abstract: In the past decade, the use of digital image correlation
(DIC) techniques has increased significantly in the area of
experimental mechanics, especially for materials behavior
characterization. This non-contact tool enables full field displacement
and strain measurements over a complete region of interest. The DIC
algorithm requires a random contrast pattern on the surface of the
specimen in order to perform properly. To create this pattern, the
specimen is usually first coated using a white matt paint. Next, a
black random speckle pattern is applied using any suitable method. If
the applied paint coating is too thick, its top surface may not be able
to exactly follow the deformation of the specimen, and consequently,
the strain measurement might be underestimated. In the present
article, a study of the influence of the paint thickness on the strain
underestimation is performed for different strain levels. The results
are then compared to typical paint coating thicknesses applied by
experienced DIC users. A slight strain underestimation was observed
for paint coatings thicker than about 30μm. On the other hand, this
value was found to be uncommonly high compared to coating
thicknesses applied by DIC users.
Abstract: To mitigate the urban heat island effect has become a
global issue when we are faced with the challenge of climate change.
Through literature review, plant photosynthesis can reduce the carbon
dioxide and mitigate the urban heat island effect to a degree. Because
there are not enough open space and parks, green roof has become an
important policy in Taiwan.
We selected elementary school buildings in northern New Taipei
City as research subjects since elementary schools are asked with
priority to build green roof and important educational place to promote
green roof concept. Testo175-H1 recording device was used to record
the temperature and humidity differences between roof surface and
interior space below roof with and without green roof in the long-term.
We also use questionnaires to investigate the awareness of comfort
level of green roof and sensation of teachers and students of the
elementary schools.
The results indicated that the temperature of roof without greening
was higher than that with greening by about 2°C. But sometimes
during noontime, the temperature of green roof was higher than that of
non-green roof probably because of the character of the accumulation
and dissipation of heat of greening. The temperature of the interior
space below green roof was normally lower than that without green
roof by about 1°C, showing that green roof could lower the
temperature. The humidity of the green roof was higher than the one
without greening also indicated that green roof retained water better.
Teachers liked to combine green roof concept in the curriculum,
and students wished all classes can take turns to maintain the green
roof. Teachers and students whose school had integrated green roof
concept in the curriculum were more willing to participate in the
maintenance work of green roof. Teachers and students who may have
access to and touch the green roof can be more aware of the green roof
benefit. We suggest architects to increase the accessibility and
visibility of green roof, such as use it as a part of the activity space.
This idea can be a reference to the green roof curriculum design.
Abstract: Students' academic achievement, along with the
effects of different variables, has been a serious concern of educators
since long ago. This study was an attempt to investigate the interplay
of Locus of Control (LOC), academic achievement and biological
variables among Iranian online EFL Learners. The participants of the
study included 100 students of different age groups and genders
studying English online at Iran Language Institute (ILI), Isfahan,
Iran. The instrument used was Trice Academic LOC questionnaire
which identifies orientations of internality or externality. The
participants' Grade Point Averages (GPAs) were used as the measure
of their academic achievement. A series of independent samples ttests
were performed on the data. The results of the study showed that
(a) there were no significant differences between male and female
participants in LOC orientation, (b) there was no relationship
between LOC and academic achievement among internal males and
females, (c) external females were better achievers than external
males, (d) and the age had no significant relationship with LOC and
academic achievement. It can be concluded that the social, cultural
patterns of genders have changed. This study might help sociologists
and psychologists as well as applied linguists in that they reflect the
recent social changes and their effects on the LOC and their
consequent implications in teaching languages.
Abstract: This article proposes a new method for application in
communication circuit systems that increase efficiency, PAE, output
power and gain in the circuit. The proposed method is based on a
combination of switching class-E and class-J and has been termed
class-EJ. This method was investigated using both theory and
simulation to confirm ∼72% PAE and output power of >39dBm. The
combination and design of the proposed power amplifier accrues gain
of over 15dB in the 2.9 to 3.5GHz frequency bandwidth. This circuit
was designed using MOSFET and high power transistors. The loadand
source-pull method achieved the best input and output networks
using lumped elements. The proposed technique was investigated for
fundamental and second harmonics having desirable amplitudes for
the output signal.