Abstract: The Orthogonal Frequency Division Multiplexing
(OFDM) with high data rate, high spectral efficiency and its ability to
mitigate the effects of multipath makes them most suitable in wireless
application. Impulsive noise distorts the OFDM transmission and
therefore methods must be investigated to suppress this noise. In this
paper, a State Space Recursive Least Square (SSRLS) algorithm
based adaptive impulsive noise suppressor for OFDM
communication system is proposed. And a comparison with another
adaptive algorithm is conducted. The state space model-dependent
recursive parameters of proposed scheme enables to achieve steady
state mean squared error (MSE), low bit error rate (BER), and faster
convergence than that of some of existing algorithm.
Abstract: Brass terminal, one of the several crude oil and
petroleum products storage/handling facilities in the Niger Delta was
built in the 1980s. Activities at this site, over the years, released
crude oil into this 3 m-deep, 1500 m-long canal lying adjacent to the
terminal with oil floating on it and its sediment heavily polluted. To
ensure effective clean-up, three major activities were planned: site
characterization, bioremediation pilot plant construction and testing
and full-scale bioremediation of contaminated sediment / bank soil by
land farming. The canal was delineated into 12 lots and each
characterized, with reference to the floating oily phase, contaminated
sediment and canal bank soil. As a result of site characterization, a
pilot plant for on-site bioremediation was designed and a treatment
basin constructed for carrying out pilot bioremediation test.
Following a designed sampling protocol, samples from this pilot
plant were collected for analysis at two laboratories as a quality
assurance / quality control check. Results showed that Brass Canal
upstream is contaminated with dark, thick and viscous oily film with
characteristic hydrocarbon smell while downstream, thin oily film
interspersed with water was observed. Sediments were observed to be
dark with mixture of brownish sandy soil with TPH ranging from
17,800 mg/kg in Lot 1 to 88,500 mg/kg in Lot 12 samples. Brass
Canal bank soil was observed to be sandy from ground surface to 3m,
below ground surface (bgs) it was silty-sandy and brownish while
subsurface soil (4-10m bgs) was sandy-clayey and whitish/grayish
with typical hydrocarbon smell. Preliminary results obtained so far
have been very promising but were proprietary. This project is
considered, to the best of technical literature knowledge, the first
large-scale on-site bioremediation project in the Niger Delta region,
Nigeria.
Abstract: In this paper, we propose a system for preventing gas
risks through the use of wireless communication modules and
intelligent gas safety appliances. Our system configuration consists of
an automatic extinguishing system, detectors, a wall-pad, and a
microcomputer controlled micom gas meter to monitor gas flow and
pressure as well as the occurrence of earthquakes. The automatic fire
extinguishing system checks for both combustible gaseous leaks and
monitors the environmental temperature, while the detector array
measures smoke and CO gas concentrations. Depending on detected
conditions, the micom gas meter cuts off an inner valve and generates
a warning, the automatic fire-extinguishing system cuts off an external
valve and sprays extinguishing materials, or the sensors generate
signals and take further action when smoke or CO are detected.
Information on intelligent measures taken by the gas safety appliances
and sensors are transmitted to the wall-pad, which in turn relays this as
real time data to a server that can be monitored via an external network
(BcN) connection to a web or mobile application for the management
of gas safety. To validate this smart-home gas management system, we
field-tested its suitability for use in Korean apartments under several
scenarios.
Abstract: Here, we study the characteristic feature of
conventional (ON-OFF keying) and soliton based transmission
system. We consider 20Gbps transmission system implemented with
Conventional Single Mode Fiber (C-SMF) to examine the role of
Gaussian pulse which is the characteristic of conventional
propagation and Hyperbolic-secant pulse which is the characteristic
of soliton propagation in it. We note the influence of these pulses
with respect to different dispersion lengths and soliton period in
conventional and soliton system respectively and evaluate the system
performance in terms of Quality factor. From the analysis, we could
prove that the soliton pulse has the consistent performance even for
long distance without dispersion compensation than the conventional
system as it is robust to dispersion. For the length of transmission of
200Km, soliton system yielded Q of 33.958 while the conventional
system totally exhausted with Q=0.
Abstract: Microstructural and hardening changes of
Fe-0.2wt.%V alloy and pure Fe irradiated with 100 keV hydrogen ions
at room temperature were investigated. It was found that dislocation
density varies dramatically after irradiation, ranging from dislocation
free to dense areas with tangled and complex dislocation
configuration. As the irradiated Fe-0.2wt.%V samples were annealed
at 773 K, the irradiation-induced dislocation loops disappear, while
many small precipitates with enriched C distribute in the matrix. Some
large precipitates with enriched V were also observed. The hardness of
Fe-0.2wt.%V alloy and pure Fe increases after irradiation, which
ascribes to the formation of dislocation loops in the irradiated
specimens. Compared with pure Fe, the size of the
irradiation-introduced dislocation loops in Fe-0.2wt.%V alloy
decreases and the density increases, the change of the hardness also
decreases.
Abstract: The separation of Hg (II) from produced water by
hollow fiber contactors (HFC) was investigation. This system
included of two hollow fiber modules in the series connecting. The
first module used for the extraction reaction and the second module
for stripping reaction. Aliquat336 extractant was fed from the organic
reservoirs into the shell side of the first hollow fiber module and
continuous to the shell side of the second module. The organic liquid
was continuously feed recirculate and back to the reservoirs. The feed
solution was pumped into the lumen (tube side) of the first hollow
fiber module. Simultaneously, the stripping solution was pumped in
the same way in tube side of the second module. The feed and
stripping solution was fed which had a countercurrent flow. Samples
were kept in the outlet of feed and stripping solution at 1 hour and
characterized concentration of Hg (II) by Inductively Couple Plasma
Atomic Emission Spectroscopy (ICP-AES). Feed solution was
produced water from natural gulf of Thailand. The extractant was
Aliquat336 dissolved in kerosene diluent. Stripping solution used was
nitric acid (HNO3) and thiourea (NH2CSNH2). The effect of carrier
concentration and type of stripping solution were investigated.
Results showed that the best condition were 10 % (v/v) Aliquat336
and 1.0 M NH2CSNH2. At the optimum condition, the extraction and
stripping of Hg (II) were 98% and 44.2%, respectively.
Abstract: Dielectric ceramic samples in the BaO-Re2O3-TiO2
ternary system were synthesized with structural formula Ba2-
xRe4+2x/3Ti8O24 where Re= rare earth metal and Re= Sm and La where
x varies from 0.0 to 0.6 with step size 0.1. Polycrystalline samples
were prepared by the conventional solid state reaction technique. The
dielectric, electrical and impedance analysis of all the samples in the
frequency range 1KHz- 1MHz at room temperature (25°C) have been
done to get the understanding of electrical conduction and dielectric
relaxation and their correlation. Dielectric response of the samples at
lower frequencies shows dielectric dispersion while at higher
frequencies it shows dielectric relaxation. The ac conductivity is well
fitted by the Jonscher law. The spectroscopic data in the impedance
plane confirms the existence of grain contribution to the relaxation.
All the properties are found out to be function of frequency as well as
the amount of substitution.
Abstract: In the present study, RBF neural networks were used
for predicting the performance and emission parameters of a
biodiesel engine. Engine experiments were carried out in a 4 stroke
diesel engine using blends of diesel and Honge methyl ester as the
fuel. Performance parameters like BTE, BSEC, Tex and emissions
from the engine were measured. These experimental results were
used for ANN modeling.
RBF center initialization was done by random selection and by
using Clustered techniques. Network was trained by using fixed and
varying widths for the RBF units. It was observed that RBF results
were having a good agreement with the experimental results.
Networks trained by using clustering technique gave better results
than using random selection of centers in terms of reduced MRE and
increased prediction accuracy. The average MRE for the performance
parameters was 3.25% with the prediction accuracy of 98% and for
emissions it was 10.4% with a prediction accuracy of 80%.
Abstract: This paper examines the utilization of public-private
partnerships for the building and operation of wastewater treatment
plants. Our research focuses on risk allocation in this kind of projects.
Our analysis builds on more than hundred wastewater treatment
plants built and operated through PPP projects in Aragon (Spain).
The paper illustrates the consequences of an inadequate management
of construction risk and an unsuitable transfer of demand risk in
wastewater treatment plants. It also shows that the involvement of
many public bodies at local, regional and national level further
increases the complexity of this kind of projects and make time
delays more likely.
Abstract: To understand the friction stir welding process, it is
very important to know the nature of the material flow in and around
the tool. The process is a combination of both thermal as well as
mechanical work i.e. it is a coupled thermo-mechanical process.
Numerical simulations are very much essential in order to obtain a
complete knowledge of the process as well as the physics underlying
it. In the present work a model based approach is adopted in order to
study material flow. A thermo-mechanical based CFD model is
developed using a Finite Element package, Comsol Multiphysics.
The fluid flow analysis is done. The model simultaneously predicts
shear strain fields, shear strain rates and shear stress over the entire
workpiece for the given conditions. The flow fields generated by the
streamline plot give an idea of the material flow. The variation of
dynamic viscosity, velocity field and shear strain fields with various
welding parameters is studied. Finally the result obtained from the
above mentioned conditions is discussed elaborately and concluded.
Abstract: The polymer foil used for manufacturing of
laminated glass members behaves in a viscoelastic manner with
temperature dependance. This contribution aims at incorporating
the time/temperature-dependent behavior of interlayer to our earlier
elastic finite element model for laminated glass beams. The model
is based on a refined beam theory: each layer behaves according
to the finite-strain shear deformable formulation by Reissner and
the adjacent layers are connected via the Lagrange multipliers
ensuring the inter-layer compatibility of a laminated unit. The
time/temperature-dependent behavior of the interlayer is accounted
for by the generalized Maxwell model and by the time-temperature
superposition principle due to the Williams, Landel, and Ferry.
The resulting system is solved by the Newton method with
consistent linearization and the viscoelastic response is determined
incrementally by the exponential algorithm. By comparing the model
predictions against available experimental data, we demonstrate that
the proposed formulation is reliable and accurately reproduces the
behavior of the laminated glass units.
Abstract: Waste load allocation (WLA) policies may use multiobjective
optimization methods to find the most appropriate and
sustainable solutions. These usually intend to simultaneously
minimize two criteria, total abatement costs (TC) and environmental
violations (EV). If other criteria, such as inequity, need for
minimization as well, it requires introducing more binary
optimizations through different scenarios. In order to reduce the
calculation steps, this study presents value index as an innovative
decision making approach. Since the value index contains both the
environmental violation and treatment costs, it can be maximized
simultaneously with the equity index. It implies that the definition of
different scenarios for environmental violations is no longer required.
Furthermore, the solution is not necessarily the point with minimized
total costs or environmental violations. This idea is testified for Haraz
River, in north of Iran. Here, the dissolved oxygen (DO) level of river
is simulated by Streeter-Phelps equation in MATLAB software. The
WLA is determined for fish farms using multi-objective particle
swarm optimization (MOPSO) in two scenarios. At first, the trade-off
curves of TC-EV and TC-Inequity are plotted separately as the
conventional approach. In the second, the Value-Equity curve is
derived. The comparative results show that the solutions are in a
similar range of inequity with lower total costs. This is due to the
freedom of environmental violation attained in value index. As a
result, the conventional approach can well be replaced by the value
index particularly for problems optimizing these objectives. This
reduces the process to achieve the best solutions and may find better
classification for scenario definition. It is also concluded that decision
makers are better to focus on value index and weighting its contents
to find the most sustainable alternatives based on their requirements.
Abstract: In this contribution two approaches for calculating
optimal trajectories for highly automated vehicles are presented and
compared. The first one is based on a non-linear vehicle model, used
for evaluation. The second one is based on a simplified model and
can be implemented on a current ECU. In usual driving situations
both approaches show very similar results.
Abstract: Channel sections are widely used in practice as beams.
However, design rules for eccentrically loaded (not through shear
center) beams with channel cross- sections are not available in
Eurocode 3. This paper compares the ultimate loads based on the
adjusted design rules for lateral torsional buckling of eccentrically
loaded channel beams in bending to the ultimate loads obtained with
Finite Element (FE) simulations on the basis of a parameter study.
Based on the proposed design rule, this study has led to a new design
rule which conforms to Eurocode 3.
Abstract: Medicinal plants are now gaining attractiveness in
treatment of bacterial infections and food preservation. The objective
of this study was to assess antibacterial activity of some medicinal
plants on pathogenic bacteria. Screening of antibacterial activity of
aqueous and methanol extracts of some plants: Jojoba, Ginger, Sage,
Thyme and Clove against Bacillus cereus, Salmonella typhimurium,
Staphylococcus aureus, Clostridium perfringens and Escherichia coli
were investigated. Antibacterial activity was performed by agar
diffusion and disc diffusion method. Jatropha, Jojoba, Clove and
Ginger extracts showed notable bacterial activity in the first
screening step then selected to be tested against Bacillus cereus
(Gram+), Staphylococcus aureus (Gram+) and Salmonella
typhimurium (Gram−) and their effect was compared using
antibiotics as control. Screening results showed potential antibacterial
activity of the tested plant extracts against the screened bacterial
strains. It was found that methanol extracts exhibited higher
antibacterial activity than aqueous extracts. Methanol extract of
Jatropha showed the highest inhibition zone against Staphylococcus
aureus (Gram+) with 24.00 mm diameter, compared to the other
plant extracts followed by clove. Meanwhile, the inhibition zones of
methanol extracts of Jojoba and Ginger were the same (12mm).The
Gram-positive bacteria were found to be more sensitive to aqueous
and methanol extracts than Gram-negative bacteria.
Abstract: In this research article of modeling Underwater
Wireless Sensor Network Simulators, we provide a comprehensive
overview of the various currently available simulators used in UWSN
modeling. In this work, we compare their working environment,
software platform, simulation language, key features, limitations and
corresponding applications. Based on extensive experimentation and
performance analysis, we provide their efficiency for specific
applications. We have also provided guidelines for developing
protocols in different layers of the protocol stack, and finally these
parameters are also compared and tabulated. This analysis is
significant for researchers and designers to find the right simulator
for their research activities.
Abstract: This paper analyses the heat transfer performance and
fluid flow using different nanofluids in a square enclosure. The
energy equation and Navier-Stokes equation are solved numerically
using finite volume scheme. The effect of volume fraction
concentration on the enhancement of heat transfer has been studied
icorporating the Brownian motion; the influence of effective thermal
conductivity on the enhancement was also investigated for a range of
volume fraction concentration. The velocity profile for different
Rayleigh number. Water-Cu, water AL2O3 and water-TiO2 were
tested.
Abstract: The article represents the results of isolation and
component chromatographic analysis of essential oils of Polygonym
L. plants growing in Kazakhstan in commercial reserves at the
territory of Kazakhstan. The results of research of antiviral activity of
isolated substances to flu virus have been represented in this article.
The main pharmacophore groups in the structure of alkaloids have
been identified.
Abstract: This paper reports a novel actuating design that uses
the shear deformation of a piezoelectric actuator to deflect a
bulge-diaphragm for driving an array microdroplet ejector. In essence,
we employed a circular-shaped actuator poled radial direction with
remnant polarization normal to the actuating electric field for inducing
the piezoelectric shear effect. The array microdroplet ejector consists
of a shear type piezoelectric actuator, a vibration plate, two chamber
plates, two channel plates and a nozzle plate. The vibration, chamber
and nozzle plate components are fabricated using nickel
electroforming technology, whereas the channel plate is fabricated by
etching of stainless steel. The diaphragm displacement was measured
by the laser two-dimensional scanning vibrometer. The ejected
droplets of the microejector were also observed via an optic
visualization system.
Abstract: The article presents a plasma chemical technology for
processing solid fuels, using examples of bituminous and brown
coals. Thermodynamic and experimental investigation of the
technology was made. The technology allows producing synthesis
gas from the coal organic mass and valuable components (technical
silicon, ferrosilicon, aluminum, and carbon silicon, as well as
microelements of rare metals, such as uranium, molybdenum,
vanadium, etc.) from the mineral mass. The thusly produced highcalorific
synthesis gas can be used for synthesis of methanol, as a
high-calorific reducing gas instead of blast-furnace coke as well as
power gas for thermal power plants.