Abstract: The study is devoted to define the optimal conditions
for the nitriding of pure iron at atmospheric pressure by using NH3-
Ar-C3H8 gas mixtures. After studying the mechanisms of phase
formation and mass transfer at the gas-solid interface, a mathematical
model is developed in order to predict the nitrogen transfer rate in the
solid, the ε-carbonitride layer growth rate and the nitrogen and
carbon concentration profiles. In order to validate the model and to
show its possibilities, it is compared with thermogravimetric
experiments, analyses and metallurgical observations (X-ray
diffraction, optical microscopy and electron microprobe analysis).
Results obtained allow us to demonstrate the sound correlation
between the experimental results and the theoretical predictions.
Abstract: Carbon nanotube is one of the most attractive materials
for the potential applications of nanotechnology due to its excellent
mechanical, thermal, electrical and optical properties. In this paper we
report a supercapacitor made of nickel foil electrodes, coated with
multiwall carbon nanotubes (MWCNTs) thin film using
electrophoretic deposition (EPD) method. Chemical vapor deposition
method was used for the growth of MWCNTs and ethanol was used as
a hydrocarbon source. High graphitic multiwall carbon nanotube was
found at 750oC analyzing by Raman spectroscopy. We observed the
electrochemical performance of supercapacitor by cyclic
voltammetry. The electrodes of supercapacitor fabricated from
MWCNTs exhibit considerably small equivalent series resistance
(ESR), and a high specific power density. Electrophoretic deposition
is an easy method in fabricating MWCNT electrodes for high
performance supercapacitor.
Abstract: In this paper a comprehensive review on various
factory layouts has been carried out for designing a lucrative process
layout for medium scale industries. Industry data base reveals that the
end product rejection rate is on the order of 10% amounting large
profit loss. In order to avoid these rejection rates and to increase the
quality product production an intermediate non-destructive testing
facility (INDTF) has been recommended for increasing the overall
profit. We observed through detailed case studies that while
introducing INDTF to medium scale industries the expensive
production process can be avoided to the defective products well
before its final shape. Additionally, the defective products identified
during the intermediate stage can be effectively utilized for other
applications or recycling; thereby the overall wastage of the raw
materials can be reduced and profit can be increased. We concluded
that the prudent design of a factory layout through critical path
method facilitating with INDTF will warrant profitable outcome.
Abstract: In this paper, Fuzzy C-Means clustering with
Expectation Maximization-Gaussian Mixture Model based hybrid
modeling algorithm is proposed for Continuous Tamil Speech
Recognition. The speech sentences from various speakers are used
for training and testing phase and objective measures are between the
proposed and existing Continuous Speech Recognition algorithms.
From the simulated results, it is observed that the proposed algorithm
improves the recognition accuracy and F-measure up to 3% as
compared to that of the existing algorithms for the speech signal from
various speakers. In addition, it reduces the Word Error Rate, Error
Rate and Error up to 4% as compared to that of the existing
algorithms. In all aspects, the proposed hybrid modeling for Tamil
speech recognition provides the significant improvements for speechto-
text conversion in various applications.
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: 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: PVC foam-fly ash composites (PVC-FA) are
characterized for their structural, morphological, mechanical and
thermal properties. The tensile strength of the composites increased
modestly with higher fly ash loading, while there was a significant
increase in the elastic modulus for the same composites. On the other
hand, a decrease in elongation at UTS was observed upon increasing
fly ash content due to increased rigidity of the composites. Similarly,
the flexural modulus increased as the fly ash loading increased,
where the composites containing 25 phr fly ash showed the highest
flexural strength. Thermal properties of PVC-fly ash composites were
determined by Thermo Gravimetric Analysis (TGA). The
microstructural properties were studied by Scanning Electron
Microscopy (SEM). SEM results confirm that fly ash particles were
mechanically interlocked in PVC matrix with good interfacial
interaction with the matrix. Particle agglomeration and debonding
was observed in samples containing higher amounts of fly ash.
Abstract: In this study, microcrystalline cellulose (MCC) was
extracted from oil palm empty fruit bunch (EFB) cellulose which was
earlier isolated from oil palm EFB fibre. In order to isolate the
cellulose, the chlorination method was carried out. Then, the MCC
was prepared by simultaneous ultrasonic and alkali treatment from
the isolated α-cellulose. Based on mass balance calculation, the yields
for MCC obtained from EFB was 44%. For fiber characterization, it
is observed that the chemical composition of the hemicellulose and
lignin for all samples decreased while composition for cellulose
increased. The structural property of the MCC was studied by X-ray
diffraction (XRD) method and the result shows that the MCC
produced is a cellulose-I polymorph, with 73% crystallinity.
Abstract: This paper discusses the role of music as a ludic
activity and constituent element of voice in the construction and
consolidation of the relationship of the baby and his/her mother or
caretaker, evaluating its implications in his/her psychic structure and
constitution as a subject. The work was based on the research
developed as part of the author’s doctoral activities carried out from
her insertion in a project of the Music Department of Federal
University of Rio Grande do Sul - UFRGS, which objective was the
development of musical activities with groups of babies from 0 to 24
months old and their caretakers. Observations, video recordings of
the meetings, audio testemonies, and evaluation tools applied to
group participants were used as instruments for this research.
Information was collected on the participation of 195 babies, among
which 8 were more focused on through interviews with their mothers
or caretakers. These interviews were analyzed based on the
referential of French Discourse Analysis, Psychoanalysis, Psychology
of Development and Musical Education. The results of the research
were complemented by other posterior experiences that the author
developed with similar groups, in a context of a private clinic. The
information collected allowed the observation of the ludic and
structural functions of musical activities, when developed in a
structured environment, as well as the importance of the musicality of
the mother’s voice to the psychical structuring of the baby, allowing
his/her insertion in the language and his/her constitution as a subject.
Abstract: Children are more susceptible to medication errors
than adults. Medication administration process is the last stage in the
medication treatment process and most of the errors detected in this
stage. Little research has been undertaken about medication errors in
children in the Middle East countries. This study was aimed to
evaluate how the paediatric nurses adhere to the medication
administration policy and also to identify any medication preparation
and administration errors or any risk factors. An observational,
prospective study of medication administration process from when
the nurses preparing patient medication until administration stage
(May to August 2014) was conducted in Saudi Arabia. Twelve
paediatric nurses serving 90 paediatric patients were observed. 456
drug administered doses were evaluated. Adherence rate was variable
in 7 steps out of 16 steps. Patient allergy information, dose
calculation, drug expiry date were the steps in medication
administration with lowest adherence rates. 63 medication
preparation and administration errors were identified with error rate
13.8% of medication administrations. No potentially life-threating
errors were witnessed. Few logistic and administrative factors were
reported. The results showed that the medication administration
policy and procedure need an urgent revision to be more sensible for
nurses in practice. Nurses’ knowledge and skills regarding to the
medication administration process should be improved.
Abstract: Animal fats (camel, sheep, goat, rabbit and chicken)
and vegetable oils (corn, sunflower, palm oil and olive oil) were
substituted with different proportions (1, 5, 10 and 20%) of lard.
Fatty acid composition in TG and 2-MG were determined using
lipase hydrolysis and gas chromatography before and after
adulteration. Results indicated that, genuine lard had a high
proportion (60.97%) of the total palmitic acid at 2-MG. However, it
was 8.70%, 16.40%, 11.38%, 10.57%, 29.97 and 8.97% for camel,
beef, sheep, goat, rabbit and chicken, respectively. It could be noticed
also the position-2-MG is mostly occupied by unsaturated fatty acids
among all tested fats except lard. Vegetable oils (corn, sunflower,
palm oil and olive oil) revealed that the levels of palmitic acid
esterifies at 2-MG position was 6.84, 1.43, 9.86 and 1.70%,
respectively. It could be observed also the studied oils had a higher
level of unsaturated fatty acids in the same position, compared with
animal fats under investigation. Moreover, palmitic acid esterifies at
2-MG and PAEF increased gradually as the substituted levels
increased among all tested fat and oil samples. Statistical analysis
showed that the PAEF correlated well with lard level. The detection
of lard in some commercial processed foods (5 French fries, 4 Butter
fats, 5 processed meat and 6 candy samples) was carried out. Results
revealed that 2 samples of French fries and 4 samples of processed
meat contained lard due to their higher PAEF, while butter fat and
candy were free of lard.
Abstract: In this paper, Least Mean Square (LMS) adaptive
noise reduction algorithm is proposed to enhance the speech signal
from the noisy speech. In this, the speech signal is enhanced by
varying the step size as the function of the input signal. Objective and
subjective measures are made under various noises for the proposed
and existing algorithms. From the experimental results, it is seen that
the proposed LMS adaptive noise reduction algorithm reduces Mean
square Error (MSE) and Log Spectral Distance (LSD) as compared to
that of the earlier methods under various noise conditions with
different input SNR levels. In addition, the proposed algorithm
increases the Peak Signal to Noise Ratio (PSNR) and Segmental SNR
improvement (ΔSNRseg) values; improves the Mean Opinion Score
(MOS) as compared to that of the various existing LMS adaptive
noise reduction algorithms. From these experimental results, it is
observed that the proposed LMS adaptive noise reduction algorithm
reduces the speech distortion and residual noise as compared to that
of the existing methods.
Abstract: A cleaner production project was implemented in a
bakery. The project is based on the substitution of the best available
technique for an obsolete leaven production technology. The new
technology enables production of durable, high-quality leavens.
Moreover, 25% of flour as the original raw material can be replaced
by pastry from the previous day production which has not been sold.
That pastry was previously disposed in a waste incineration plant.
Besides the environmental benefits resulting from less waste, lower
consumption of energy, reduction of sewage waters quantity and
floury dustiness there are also significant economic benefits. Payback
period of investment was calculated with help of static method of
financial analysis about 2.6 years, using dynamic method 3.5 years
and an internal rate of return more than 29%. The supposed annual
average profit after taxationin the second year of operation was
incompliance with the real profit.
Abstract: As enterprise computing becomes more and more
complex, the costs and technical challenges of IT system maintenance
and support are increasing rapidly. One popular approach to managing
IT system maintenance is to prepare and use a FAQ (Frequently Asked
Questions) system to manage and reuse systems knowledge. Such a
FAQ system can help reduce the resolution time for each service
incident ticket. However, there is a major problem where over time the
knowledge in such FAQs tends to become outdated. Much of the
knowledge captured in the FAQ requires periodic updates in response
to new insights or new trends in the problems addressed in order to
maintain its usefulness for problem resolution. These updates require a
systematic approach to define the exact portion of the FAQ and its
content. Therefore, we are working on a novel method to
hierarchically structure the FAQ and automate the updates of its
structure and content. We use structured information and the
unstructured text information with the timelines of the information in
the service incident tickets. We cluster the tickets by structured
category information, by keywords, and by keyword modifiers for the
unstructured text information. We also calculate an urgency score
based on trends, resolution times, and priorities. We carefully studied
the tickets of one of our projects over a 2.5-year time period. After the
first 6 months we started to create FAQs and confirmed they improved
the resolution times. We continued observing over the next 2 years to
assess the ongoing effectiveness of our method for the automatic FAQ
updates. We improved the ratio of tickets covered by the FAQ from
32.3% to 68.9% during this time. Also, the average time reduction of
ticket resolution was between 31.6% and 43.9%. Subjective analysis
showed more than 75% reported that the FAQ system was useful in
reducing ticket resolution times.
Abstract: The purpose of this study is to compare Self
Compacting Concrete (SCC) and Conventional Concrete (CC) in
terms of their capillary water absorption. During the comparison of
SCC and CC, the effects of two different factors were also
investigated: concrete strength class and curing condition. In the
study, both SCC and CC were produced in three different concrete
classes (C25, C50 and C70) and the other parameter (i.e. curing
condition) was determined as two levels: moisture and air curing. It
was observed that, for both curing environments and all strength
classes of concrete, SCCs had lower capillary water absorption values
than that of CCs. It was also detected that, for both SCC and CC,
capillary water absorption values of samples kept in moisture curing
were significantly lower than that of samples stored in air curing.
Additionally, it was determined that capillary water absorption values
for both SCC and CC decrease with increasing strength class of
concrete for both curing environments.
Abstract: Comprehensive numerical studies have been carried
out to examine the best aerodynamic performance of subsonic aircraft
at different winglet cant angles using a validated 3D k-ω SST model.
In the parametric analytical studies NACA series of airfoils are
selected. Basic design of the winglet is selected from the literature
and flow features of the entire wing including the winglet tip effects
have been examined with different cant angles varying from 150 to
600 at different angles of attack up to 140. We have observed, among
the cases considered in this study that a case, with 150 cant angle the
aerodynamics performance of the subsonic aircraft during takeoff
was found better up to an angle of attack of 2.80 and further its
performance got diminished at higher angles of attack. Analyses
further revealed that increasing the winglet cant angle from 150 to 600
at higher angles of attack could negate the performance deterioration
and additionally it could enhance the peak CL/CD on the order of
3.5%. The investigated concept of variable-cant-angle winglets
appears to be a promising alternative for improving the aerodynamic
efficiency of aircraft.
Abstract: Due to the determination of the pollution status of
fresh resources in the Egyptian territorial waters is very important for
public health; this study was carried out to reveal the levels of heavy
metals in the shellfish and their environment and its relation to the
highly developed industrial activities in those areas. A total of 100
shellfish samples from the Rosetta, Edku, El-Maadiya, Abo-Kir and
El-Max coasts [10 crustaceans (shrimp) and 10 mollusks (oysters)]
were randomly collected from each coast. Additionally, 10 samples
from both the water and the sediment were collected from each coast.
Each collected sample was analyzed for cadmium, chromium,
copper, lead and zinc residues using a Perkin Elmer atomic
absorption spectrophotometer (AAS). The results showed that the
levels of heavy metals were higher in the water and sediment from
Abo-Kir. The heavy metal levels decreased successively for the
Rosetta, Edku, El-Maadiya, and El-Max coasts, and the
concentrations of heavy metals, except copper and zinc, in shellfish
exhibited the same pattern. For the concentration of heavy metals in
shellfish tissue, the highest was zinc and the concentrations decreased
successively for copper, lead, chromium and cadmium for all coasts,
except the Abo-Kir coast, where the chromium level was highest and
the other metals decreased successively for zinc, copper, lead and
cadmium. In Rosetta, chromium was higher only in the mollusks,
while the level of this metal was lower in the crustaceans; this trend
was observed at the Edku, El-Maadiya and El-Max coasts as well.
Herein, we discuss the importance of such contamination for public
health and the sources of shellfish contamination with heavy metals.
We suggest measures to minimize and prevent these pollutants in the
aquatic environment and, furthermore, how to protect humans from
excessive intake.
Abstract: In this paper, the influence of upstream structures on the flow patternaround and inside the wind-catcher is experimentally investigated by smoke flow visualization techniques. Wind-catchers are an important part of natural ventilation in residential buildings or public places such as shopping centers, libraries, etc. Wind-catchers might be also used in places of high urban densities; hence their potential to provide natural ventilation is dependent on the presence of upstream structures. In this study, the two-sided wind-catcher model was based on a real wind-catcher observed in the city of Yazd, Iran. The present study focuses on the flow patterns around and inside the isolated two-sided wind-catcher, and on a two-sided wind-catcher in the presence of an upstream structure. The results show that the presence of an upstream structure influences the airflow pattern force and direction. Placing a high upstream structure reverses the airflow direction inside the wind-catcher.
Abstract: To elucidate the material characteristics of single
crystals of pure aluminum and copper, the respective relations between
crystallographic orientations and microstructures were examined,
along with bending and mechanical properties. The texture
distribution was also analysed. Bending tests were performed in a
SEM apparatus while its behaviors were observed. Some analytical
results related to crystal direction maps, inverse pole figures, and
textures were obtained from electron backscatter diffraction (EBSD)
analyses.
Abstract: The knowledge of biodiesel density over large ranges
of temperature and pressure is important for predicting the behavior
of fuel injection and combustion systems in diesel engines, and for
the optimization of such systems. In this study, cottonseed oil was
transesterified into biodiesel and its density was measured at
temperatures between 288 K and 358 K and pressures between 0.1
MPa and 30 MPa, with expanded uncertainty estimated as ±1.6 kg⋅m-
3. Experimental pressure-volume-temperature (pVT) cottonseed data
was used along with literature data relative to other 18 biodiesels, in
order to build a database used to test the correlation of density with
temperarure and pressure using the Goharshadi–Morsali–Abbaspour
equation of state (GMA EoS). To our knowledge, this is the first that
density measurements are presented for cottonseed biodiesel under
such high pressures, and the GMA EoS used to model biodiesel
density. The new tested EoS allowed correlations within 0.2 kg·m-3
corresponding to average relative deviations within 0.02%. The built
database was used to develop and test a new full predictive model
derived from the observed linear relation between density and degree
of unsaturation (DU), which depended from biodiesel FAMEs
profile. The average density deviation of this method was only about
3 kg.m-3 within the temperature and pressure limits of application.
These results represent appreciable improvements in the context of
density prediction at high pressure when compared with other
equations of state.