Abstract: The use of titanium fluoride and iron fluoride
(TiF3/FeF3) catalysts in combination with polutetrafluoroethylene
(PTFE) in plain zinc- dialkyldithiophosphate (ZDDP) oil is important
for the study of engine tribocomponents and is increasingly a strategy
to improve the formation of tribofilm and provide low friction and
excellent wear protection in reduced phosphorus plain ZDDP oil. The
influence of surface roughness and the concentration of
TiF3/FeF3/PTFE were investigated using bearing steel samples
dipped in lubricant solution at 100°C for two different heating time
durations. This paper addresses the effects of water drop contact
angle using different surface; finishes after treating them with
different lubricant combination. The calculated water drop contact
angles were analyzed using Design of Experiment software (DOE)
and it was determined that a 0.05 μm Ra surface roughness would
provide an excellent TiF3/FeF3/PTFE coating for antiwear resistance
as reflected in the Scanning electron microscopy (SEM) images and
the tribological testing under extreme pressure conditions. Both
friction and wear performance depend greatly on the PTFE/and
catalysts in plain ZDDP oil with 0.05 % phosphorous and on the
surface finish of bearing steel. The friction and wear reducing effects,
which was observed in the tribological tests, indicated a better micro
lubrication effect of the 0.05 μm Ra surface roughness treated at
100°C for 24 hours when compared to the 0.1 μm Ra surface
roughness with the same treatment.
Abstract: In this paper, the secure BioSemantic Scheme is
presented to bridge biological/biomedical research problems and
computational solutions via semantic computing. Due to the diversity
of problems in various research fields, the semantic capability
description language (SCDL) plays and important role as a common
language and generic form for problem formalization. SCDL is
expected the essential for future semantic and logical computing in
Biosemantic field. We show several example to Biomedical problems
in this paper. Moreover, in the coming age of cloud computing, the
security problem is considered to be crucial issue and we presented a
practical scheme to cope with this problem.
Abstract: The aim of the present study is to investigate
consumers' determinants of intention toward the adoption of Smart
Grid solutions and technologies. Ajzen's Theory of Planned
Behaviour (TPB) model is applied and tested to explain the formation
of such adoption intention. An exogenous variable, taking into
account the resistance to change of individuals, was added to the
basic model. The elicitation study allowed obtaining salient modal
beliefs, which were used, with the support of literature, to design the
questionnaire. After the screening phase, data collected from the
main survey were analysed for evaluating measurement model's
reliability and validity. Consistent with the theory, the results of
structural equation analysis revealed that attitude, subjective norm,
and perceived behavioural control positively, which affected the
adoption intention. Specifically, the variable with the highest estimate
loading factor was found to be the perceived behavioural control,
and, the most important belief related to each construct was
determined (e.g., energy saving was observed to be the most
significant belief linked with attitude). Further investigation indicated
that the added exogenous variable has a negative influence on
intention; this finding confirmed partially the hypothesis, since this
influence was indirect: such relationship was mediated by attitude.
Implications and suggestions for future research are discussed.
Abstract: Chalcopyrite (CuFeS2) is the most common primary
mineral used for the commercial production of copper. The low
dissolution efficiency of chalcopyrite in sulfate media has prevented
an efficient industrial leaching of this mineral in sulfate media. Ferric
ions, bacteria, oxygen and other oxidants have been used as oxidizing
agents in the leaching of chalcopyrite in sulfate and chloride media
under atmospheric or pressure leaching conditions. Two leaching
methods were studied to evaluate chalcopyrite (CuFeS2) dissolution
in acid media. First, the conventional oxidative acid leaching method
was carried out using sulfuric acid (H2SO4) and potassium
dichromate (K2Cr2O7) as oxidant at atmospheric pressure. Second,
microwave-assisted acid leaching was performed using the
microwave accelerated reaction system (MARS) for same reaction
media. Parameters affecting the copper extraction such as leaching
time, leaching temperature, concentration of H2SO4 and
concentration of K2Cr2O7 were investigated. The results of
conventional acid leaching experiments were compared to the
microwave leaching method. It was found that the copper extraction
obtained under high temperature and high concentrations of oxidant
with microwave leaching is higher than those obtained
conventionally. 81% copper extraction was obtained by the
conventional oxidative acid leaching method in 180 min, with the
concentration of 0.3 mol/L K2Cr2O7 in 0.5M H2SO4 at 50 ºC, while
93.5% copper extraction was obtained in 60 min with microwave
leaching method under same conditions.
Abstract: To tackle the air pollution issues, Plug-in Hybrid
Electric Vehicles (PHEVs) are proposed as an appropriate solution.
Charging a large amount of PHEV batteries, if not controlled, would
have negative impacts on the distribution system. The control process
of charging of these vehicles can be centralized in parking lots that
may provide a chance for better coordination than the individual
charging in houses. In this paper, an optimization-based approach is
proposed to determine the optimum PHEV parking capacities in
candidate nodes of the distribution system. In so doing, a profile for
charging and discharging of PHEVs is developed in order to flatten
the network load profile. Then, this profile is used in solving an
optimization problem to minimize the distribution system losses. The
outputs of the proposed method are the proper place for PHEV
parking lots and optimum capacity for each parking. The application
of the proposed method on the IEEE-34 node test feeder verifies the
effectiveness of the method.
Abstract: Cross-linked konjac glucomannan and kappa
carrageenan film were prepared by chemical crosslinking using
glutaraldehyde (GA) as the crosslinking agent. The effect
crosslinking on the swelling degree was investigated. Konjac
glucomannan and its mixture with kappa carrageenan film was
immersed in GA solution and then thermally cured. The obtained
cross-linked film was washed and soaked in the ethanol to remove
the unreacted GA. The obtained film was air dried at room
temperature to a constant weight. The infrared spectra and the value
of swelling degree of obtained crosslinked film showed that
glucomannan and kappa carrageenan was able to be cross-linked
using glutaraldehyde by film immersion and curing method without
catalyst. The cross-linked films were found to be pH sensitive,
indicating a potential to be used in drug delivery polymer system.
Abstract: The current paper presents an extensive bottom-up
framework for assessing building sector-specific vulnerability to
climate change: energy supply and demand. The research focuses on
the application of downscaled seasonal models for estimating energy
performance of buildings in Greece. The ARW-WRF model has
been set-up and suitably parameterized to produce downscaled
climatological fields for Greece, forced by the output of the CFSv2
model. The outer domain, D01/Europe, included 345 x 345 cells of
horizontal resolution 20 x 20 km2 and the inner domain, D02/Greece,
comprised 180 x 180 cells of 5 x 5 km2 horizontal resolution. The
model run has been setup for a period with a forecast horizon of 6
months, storing outputs on a six hourly basis.
Abstract: The goal of this paper is to present the diagnostic
contribution that the screening instrument, Mini-Mental State
Examination-2: Expanded Version (MMSE-2:EV), brings in
detecting the cognitive impairment or in monitoring the progress of
degenerative disorders. The diagnostic signification is underlined by
the interpretation of the MMSE-2:EV scores, resulted from the test
application to patients with mild and major neurocognitive disorders.
The cases were selected from current practice, in order to cover vast
and significant neurocognitive pathology: mild cognitive impairment,
Alzheimer’s disease, vascular dementia, mixed dementia, Parkinson’s
disease, conversion of the mild cognitive impairment into
Alzheimer’s disease. The MMSE-2:EV version was used: it was
applied one month after the initial assessment, three months after the
first reevaluation and then every six months, alternating the blue and
red forms. Correlated with age and educational level, the raw scores
were converted in T scores and then, with the mean and the standard
deviation, the z scores were calculated. The differences of raw scores
between the evaluations were analyzed from the point of view of
statistic signification, in order to establish the progression in time of
the disease. The results indicated that the psycho-diagnostic approach
for the evaluation of the cognitive impairment with MMSE-2:EV is
safe and the application interval is optimal. In clinical settings with a
large flux of patients, the application of the MMSE-2:EV is a safe
and fast psychodiagnostic solution. The clinicians can draw objective
decisions and for the patients: it does not take too much time and
energy, it does not bother them and it doesn’t force them to travel
frequently.
Abstract: Typical load-bearing biological materials like bone,
mineralized tendon and shell, are biocomposites made from both
organic (collagen) and inorganic (biomineral) materials. This
amazing class of materials with intrinsic internally designed
hierarchical structures show superior mechanical properties with
regard to their weak components from which they are formed.
Extensive investigations concentrating on static loading conditions
have been done to study the biological materials failure. However,
most of the damage and failure mechanisms in load-bearing
biological materials will occur whenever their structures are exposed
to dynamic loading conditions. The main question needed to be
answered here is: What is the relation between the layout and
architecture of the load-bearing biological materials and their
dynamic behavior? In this work, a staggered model has been
developed based on the structure of natural materials at nanoscale and
Finite Element Analysis (FEA) has been used to study the dynamic
behavior of the structure of load-bearing biological materials to
answer why the staggered arrangement has been selected by nature to
make the nanocomposite structure of most of the biological materials.
The results showed that the staggered structures will efficiently
attenuate the stress wave rather than the layered structure.
Furthermore, such staggered architecture is effectively in charge of
utilizing the capacity of the biostructure to resist both normal and
shear loads. In this work, the geometrical parameters of the model
like the thickness and aspect ratio of the mineral inclusions selected
from the typical range of the experimentally observed feature sizes
and layout dimensions of the biological materials such as bone and
mineralized tendon. Furthermore, the numerical results validated with
existing theoretical solutions. Findings of the present work emphasize
on the significant effects of dynamic behavior on the natural
evolution of load-bearing biological materials and can help scientists
to design bioinspired materials in the laboratories.
Abstract: Ceramic Waste Aggregates (CWAs) were made from
electric porcelain insulator wastes supplied from an electric power
company, which were crushed and ground to fine aggregate sizes. In
this study, to develop the CWA mortar as an eco–efficient, ground
granulated blast–furnace slag (GGBS) as a Supplementary
Cementitious Material (SCM) was incorporated. The water–to–binder
ratio (W/B) of the CWA mortars was varied at 0.4, 0.5, and 0.6. The
cement of the CWA mortar was replaced by GGBS at 20 and 40% by
volume (at about 18 and 37% by weight). Mechanical properties of
compressive and splitting tensile strengths, and elastic modulus were
evaluated at the age of 7, 28, and 91 days. Moreover, the chloride
ingress test was carried out on the CWA mortars in a 5.0% NaCl
solution for 48 weeks. The chloride diffusion was assessed by using an
electron probe microanalysis (EPMA). To consider the relation of the
apparent chloride diffusion coefficient and the pore size, the pore size
distribution test was also performed using a mercury intrusion
porosimetry at the same time with the EPMA. The compressive
strength of the CWA mortars with the GGBS was higher than that
without the GGBS at the age of 28 and 91 days. The resistance to the
chloride ingress of the CWA mortar was effective in proportion to the
GGBS replacement level.
Abstract: This paper presents an approach of on-line control of
the state of technosphere and environment objects based on the
integration of Data Warehouse, OLAP and Expert systems
technologies. It looks at the structure and content of data warehouse
that provides consolidation and storage of monitoring data. There is a
description of OLAP-models that provide a multidimensional
analysis of monitoring data and dynamic analysis of principal
parameters of controlled objects. The authors suggest some criteria of
emergency risk assessment using expert knowledge about danger
levels. It is demonstrated now some of the proposed solutions could
be adopted in territorial decision making support systems.
Operational control allows authorities to detect threat, prevent natural
and anthropogenic emergencies and ensure a comprehensive safety of
territory.
Abstract: The lifetime of a wireless sensor network can be
effectively increased by using scheduling operations. Once the
sensors are randomly deployed, the task at hand is to find the largest
number of disjoint sets of sensors such that every sensor set provides
complete coverage of the target area. At any instant, only one of these
disjoint sets is switched on, while all other are switched off. This
paper proposes a heuristic search method to find the maximum
number of disjoint sets that completely cover the region. A
population of randomly initialized members is made to explore the
solution space. A set of heuristics has been applied to guide the
members to a possible solution in their neighborhood. The heuristics
escalate the convergence of the algorithm. The best solution explored
by the population is recorded and is continuously updated. The
proposed algorithm has been tested for applications which require
sensing of multiple target points, referred to as point coverage
applications. Results show that the proposed algorithm outclasses the
existing algorithms. It always finds the optimum solution, and that
too by making fewer number of fitness function evaluations than the
existing approaches.
Abstract: Biodiesel production from vegetable oil will produce
glycerol as by-product about 10% of the biodiesel production. The
amount of glycerol that was produced needed alternative way to
handling immediately so as to not become the waste that polluted
environment. One of the solutions was to process glycerol to
polyglycidyl nitrate (PGN). PGN is synthesized from glycerol by
three-step reactions i.e. nitration of glycerol, cyclization of 13-
dinitroglycerine and polymerization of glycosyl nitrate. Optimum
condition of nitration of glycerol with nitric acid has not been known.
Thermodynamic feasibility should be done before run experiments in
the laboratory. The aim of this study was to determine the parameters
those affect nitration of glycerol and nitric acid and chose the
operation condition. Many parameters were simulated to verify its
possibility to experiment under conditions which would get the
highest conversion of 1, 3-dinitroglycerine and which was the ideal
condition to get it. The parameters that need to be studied to obtain
the highest conversion of 1, 3-dinitroglycerine were mol ratio of
nitric acid/glycerol, reaction temperature, mol ratio of
glycerol/dichloromethane and pressure. The highest conversion was
obtained in the range of mol ratio of nitric acid /glycerol between 2/1
– 5/1, reaction temperature of 5-25oC and pressure of 1 atm. The
parameters that need to be studied further to obtain the highest
conversion of 1.3 DNG are mol ratio of nitric acid/glycerol and
reaction temperature.
Abstract: Superabsorbent polymers received much attention and
are used in many fields because of their superior characters to
traditional absorbents, e.g., sponge and cotton. So, it is very
important but challenging to prepare highly and fast-swelling
superabsorbents. A reliable, efficient and low-cost technique for
removing heavy metal ions from wastewater is the adsorption using
bio-adsorbents obtained from biological materials, such as
polysaccharides-based hydrogels superabsorbents. In this study, novel multi-functional superabsorbent composites
type semi-interpenetrating polymer networks (Semi-IPNs) were
prepared via graft polymerization of acrylamide onto chitosan
backbone in presence of gelatin, CTS-g-PAAm/Ge, using potassium
persulfate and N,N’-methylene bisacrylamide as initiator and
crosslinker, respectively. These hydrogels were also partially
hydrolyzed to achieve superabsorbents with ampholytic properties
and uppermost swelling capacity. The formation of the grafted
network was evidenced by Fourier Transform Infrared Spectroscopy
(ATR-FTIR) and Thermogravimetric Analysis (TGA). The porous
structures were observed by Scanning Electron Microscope (SEM).
From TGA analysis, it was concluded that the incorporation of the Ge
in the CTS-g-PAAm network has marginally affected its thermal
stability. The effect of gelatin content on the swelling capacities of
these superabsorbent composites was examined in various media
(distilled water, saline and pH-solutions). The water absorbency was
enhanced by adding Ge in the network, where the optimum value was
reached at 2 wt. % of Ge. Their hydrolysis has not only greatly
optimized their absorption capacity but also improved the swelling
kinetic.These materials have also showed reswelling ability. We
believe that these super-absorbing materials would be very effective
for the adsorption of harmful metal ions from wastewater.
Abstract: This paper describes a new approach which can be
used to interpret the experimental creep deformation data obtained
from miniaturized thin plate bending specimen test to the
corresponding uniaxial data based on an inversed application of the
reference stress method. The geometry of the thin plate is fully
defined by the span of the support, l, the width, b, and the thickness,
d. Firstly, analytical solutions for the steady-state, load-line creep
deformation rate of the thin plates for a Norton’s power law under
plane stress (b→0) and plane strain (b→∞) conditions were obtained,
from which it can be seen that the load-line deformation rate of the
thin plate under plane-stress conditions is much higher than that
under the plane-strain conditions. Since analytical solution is not
available for the plates with random b-values, finite element (FE)
analyses are used to obtain the solutions. Based on the FE results
obtained for various b/l ratios and creep exponent, n, as well as the
analytical solutions under plane stress and plane strain conditions, an
approximate, numerical solutions for the deformation rate are
obtained by curve fitting. Using these solutions, a reference stress
method is utilised to establish the conversion relationships between
the applied load and the equivalent uniaxial stress and between the
creep deformations of thin plate and the equivalent uniaxial creep
strains. Finally, the accuracy of the empirical solution was assessed
by using a set of “theoretical” experimental data.
Abstract: Steepest descent method is a simple gradient method
for optimization. This method has a slow convergence in heading to
the optimal solution, which occurs because of the zigzag form of the
steps. Barzilai and Borwein modified this algorithm so that it
performs well for problems with large dimensions. Barzilai and
Borwein method results have sparked a lot of research on the method
of steepest descent, including alternate minimization gradient method
and Yuan method. Inspired by previous works, we modified the step
size of the steepest descent method. We then compare the
modification results against the Barzilai and Borwein method,
alternate minimization gradient method and Yuan method for
quadratic function cases in terms of the iterations number and the
running time. The average results indicate that the steepest descent
method with the new step sizes provide good results for small
dimensions and able to compete with the results of Barzilai and
Borwein method and the alternate minimization gradient method for
large dimensions. The new step sizes have faster convergence
compared to the other methods, especially for cases with large
dimensions.
Abstract: In present global scenario, aluminum alloys are
coining the attention of many innovators as competing structural
materials for automotive and space applications. Comparing to other
challenging alloys, especially, 7xxx series aluminum alloys have
been studied seriously because of benefits such as moderate strength;
better deforming characteristics and affordable cost. It is expected
that substitution of aluminum alloys for steels will result in great
improvements in energy economy, durability and recyclability.
However, it is necessary to improve the strength and the formability
levels at low temperatures in aluminum alloys for still better
applications. Aluminum–Zinc–Magnesium with or without other
wetting agent denoted as 7XXX series alloys are medium strength
heat treatable alloys. In addition to Zn, Mg as major alloying
additions, Cu, Mn and Si are the other solute elements which
contribute for the improvement in mechanical properties by suitable
heat treatment process. Subjecting to suitable treatments like age
hardening or cold deformation assisted heat treatments; known as low
temperature thermomechanical treatments (LTMT) the challenging
properties might be incorporated. T6 is the age hardening or
precipitation hardening process with artificial aging cycle whereas T8
comprises of LTMT treatment aged artificially with X% cold
deformation. When the cold deformation is provided after solution
treatment, there is increase in hardness related properties such as
wear resistance, yield and ultimate strength, toughness with the
expense of ductility. During precipitation hardening both hardness
and strength of the samples are increasing. The hardness value may
further improve when room temperature deformation is positively
supported with age hardening known as thermomechanical treatment.
It is intended to perform heat treatment and evaluate hardness, tensile
strength, wear resistance and distribution pattern of reinforcement in
the matrix. 2 to 2.5 and 3 to 3.5 times increase in hardness is reported
in age hardening and LTMT treatments respectively as compared to
as-cast composite. There was better distribution of reinforcements in
the matrix, nearly two fold increase in strength levels and up to 5
times increase in wear resistance are also observed in the present
study.
Abstract: Despite the advances made in various new
technologies, application of these technologies for agriculture still
remains a formidable task, as it involves integration of diverse
domains for monitoring the different process involved in agricultural
management. Advances in ambient intelligence technology represents
one of the most powerful technology for increasing the yield of
agricultural crops and to mitigate the impact of water scarcity,
climatic change and methods for managing pests, weeds and diseases.
This paper proposes a GPS-assisted, machine to machine solutions
that combine information collected by multiple sensors for the
automated management of paddy crops. To maintain the economic
viability of paddy cultivation, the various techniques used in
agriculture are discussed and a novel system which uses ambient
intelligence technique is proposed in this paper. The ambient
intelligence based agricultural system gives a great scope.
Abstract: Acoustic properties of polymeric liquids are high
sensitive to free gas traces in the form of fine bubbles. Their presence
is typical for such liquids because of chemical reactions, small
wettability of solid boundaries, trapping of air in technological
operations, etc. Liquid temperature influences essentially its
rheological properties, which may have an impact on the bubble
pulsations and sound propagation in the system. The target of the
paper is modeling of the liquid temperature effect on single bubble
dynamics and sound dispersion and attenuation in polymeric solution
with spherical gas bubbles. The basic sources of attenuation (heat
exchange between gas in microbubbles and surrounding liquid,
rheological and acoustic losses) are taken into account. It is supposed
that in the studied temperature range the interface mass transfer has a
minor effect on bubble dynamics. The results of the study indicate
that temperature raise yields enhancement of bubble pulsations and
increase in sound attenuation in the near-resonance range and may
have a strong impact on sound dispersion in the liquid-bubble
mixture at frequencies close to the resonance frequency of bubbles.
Abstract: The using of waste materials in the construction
industry can reduce the dependence on the natural aggregates which
are going at the end to deplete. The glass waste is generated in a huge
amount which can make one of its disposals in concrete industry
effective not only as a green solution but also as an advantage to
enhance the performance of mechanical properties and durability of
concrete. This article reports the performance of concrete specimens
containing different percentages of milled glass waste as a partial
replacement of cement (Powder), when they are subject to cycles of
freezing and thawing. The tests were conducted on 75-mm cubes and
75 x 75 x 300-mm prisms. Compressive strength based on laboratory
testing and non-destructive ultrasonic pulse velocity test were
performed during the action of freezing-thawing cycles (F/T). The
results revealed that the incorporation of glass waste in concrete
mixtures is not only feasible but also showed generally better strength
and durability performance than control concrete mixture. It may be
said that the recycling of waste glass in concrete mixes is not only a
disposal way, but also it can be an exploitation in concrete industry.