Abstract: Excessive fretting wear at the taper-trunnion junction
(trunnionosis) apparently contributes to the high failure rates of hip
implants. Implant wear and corrosion lead to the release of metal
particulate debris and subsequent release of metal ions at the tapertrunnion
surface. This results in a type of metal poisoning referred to
as metallosis. The consequences of metal poisoning include;
osteolysis (bone loss), osteoarthritis (pain), aseptic loosening of the
prosthesis and revision surgery. Follow up after revision surgery,
metal debris particles are commonly found in numerous locations. Background: A stable connection between the femoral ball head
(taper) and stem (trunnion) is necessary to prevent relative motions
and corrosion at the taper junction. Hence, the importance of
component assembly cannot be over-emphasized. Therefore, the aim
of this study is to determine the influence of head-stem junction
assembly by press fitting and the subsequent
disengagement/disassembly on the connection strength between the
taper ball head and stem. Methods: CoCr femoral heads were assembled with High stainless
hydrogen steel stem (trunnion) by Push-in i.e. press fit; and
disengaged by pull-out test. The strength and stability of the two
connections were evaluated by measuring the head pull-out forces
according to ISO 7206-10 standards. Findings: The head-stem junction strength linearly increases with
assembly forces.
Abstract: This paper addresses the problem of offline path
planning for Unmanned Aerial Vehicles (UAVs) in complex threedimensional
environment with obstacles, which is modelled by 3D
Cartesian grid system. Path planning for UAVs require the
computational intelligence methods to move aerial vehicles along the
flight path effectively to target while avoiding obstacles. In this paper
Modified Particle Swarm Optimization (MPSO) algorithm is applied
to generate the optimal collision free 3D flight path for UAV. The
simulations results clearly demonstrate effectiveness of the proposed
algorithm in guiding UAV to the final destination by providing
optimal feasible path quickly and effectively.
Abstract: Brain-Computer Interfaces (BCIs) measure brain
signals activity, intentionally and unintentionally induced by users,
and provides a communication channel without depending on the
brain’s normal peripheral nerves and muscles output pathway.
Feature Selection (FS) is a global optimization machine learning
problem that reduces features, removes irrelevant and noisy data
resulting in acceptable recognition accuracy. It is a vital step
affecting pattern recognition system performance. This study presents
a new Binary Particle Swarm Optimization (BPSO) based feature
selection algorithm. Multi-layer Perceptron Neural Network
(MLPNN) classifier with backpropagation training algorithm and
Levenberg-Marquardt training algorithm classify selected features.
Abstract: Targeted drug delivery is a method of delivering
medication to a patient in a manner that increases the concentration
of the medication in some parts of the body relative to others.
Targeted drug delivery seeks to concentrate the medication in the
tissues of interest while reducing the relative concentration of the
medication in the remaining tissues. This improves efficacy of the
while reducing side effects. In the present work, we investigate the
effect of magnetic field, flow rate and particle concentration on the
capturing of magnetic particles transported in a stent implanted
fluidic channel. Iron oxide magnetic nanoparticles (Fe3O4)
nanoparticles were synthesized via co-precipitation method. The
synthesized Fe3O4 nanoparticles were added in the de-ionized (DI)
water to prepare the Fe3O4 magnetic particle suspended fluid. This
fluid is transported in a cylindrical tube of diameter 8 mm with help
of a peristaltic pump at different flow rate (25-40 ml/min). A
ferromagnetic coil of SS 430 has been implanted inside the
cylindrical tube to enhance the capturing of magnetic nanoparticles
under magnetic field. The capturing of magnetic nanoparticles was
observed at different magnetic magnetic field, flow rate and particle
concentration. It is observed that capture efficiency increases from
47-67% at magnetic field 2-5kG, respectively at particle
concentration 0.6mg/ml and at flow rate 30 ml/min. However, the
capture efficiency decreases from 65 to 44% by increasing the flow
rate from 25 to 40 ml/min, respectively. Furthermore, it is observed
that capture efficiency increases from 51 to 67% by increasing the
particle concentration from 0.3 to 0.6 mg/ml, respectively.
Abstract: This paper presents a comparative analysis of
continuously stirred tank reactor (CSTR) control based on adaptive
control and optimal tuning of PID control based on particle swarm
optimization. In the design of adaptive control, Model reference
adaptive control (MRAC) scheme is used, in which the adaptation
law have been developed by MIT rule & Lyapunov’s rule. In PSO
control parameters of PID controller is tuned by using the concept of
particle swarm optimization to get optimized operating point for
minimum integral square error (ISE) condition. The results show the
adjustment of PID parameters converting into the optimal operating
point and the good control response can be obtained by the PSO
technique.
Abstract: In this numerical study, effects of using Al2O3-water
nanofluid on the rate of heat transfer have been investigated. Physical
model is a square enclosure with insulated top and bottom horizontal
walls, while the vertical walls are kept at different constant
temperatures. Two appropriate models are used to evaluate the
viscosity and thermal conductivity of nanofluid. The governing
stream-vorticity equations are solved using a second order central
finite difference scheme, coupled to the conservation of mass and
energy. The study has been carried out for the nanoparticle diameter
30, 60 and 90 nm and the solid volume fraction 0 to 0.04. Results are
presented by average Nusselt number and normalized Nusselt number
in different range of φ and D for mixed convection dominated
regime. It is found that different heat transfer rate is predicted when
the effect of nanoparticle diameter is taken into account.
Abstract: In IA-MDT, the magnetic implants are placed
strategically at the target site to greatly and locally increase the
magnetic force on MDCPs and help to attract and retain the MDCPs
at the targeted region. In the present work, we develop a
mathematical model to study the capturing of magnetic nanoparticles
flowing within a fluid in an implant assisted cylindrical channel
under magnetic field. A coil of ferromagnetic SS-430 has been
implanted inside the cylindrical channel to enhance the capturing of
magnetic nanoparticles under magnetic field. The dominant magnetic
and drag forces, which significantly affect the capturing of
nanoparticles, are incorporated in the model. It is observed through
model results that capture efficiency increases as we increase the
magnetic field from 0.1 to 0.5 T, respectively. The increase in capture
efficiency by increase in magnetic field is because as the magnetic
field increases, the magnetization force, which is attractive in nature
and responsible to attract or capture the magnetic particles, increases
and results the capturing of large number of magnetic particles due to
high strength of attractive magnetic force.
Abstract: Rice Husk (RH) is the major byproduct in the
processing of paddy rice. The management of this waste has become
a big challenge to some of the rice producers, some of these wastes
are left in open dumps while some are burn in the open space, and
these two actions have been contributing to environmental pollution.
This study evaluates an alternative waste management of this
agricultural product for use as a civil engineering material. The RH
was burn in a controlled environment to form Rice Husk Ash (RHA).
The RHA was mix with lateritic clay at 0, 2, 4, 6, 8, and 10%
proportion by weight. Chemical test was conducted on the open burn
and controlled burn RHA with the lateritic clay. Physical test such as
particle size distribution, Atterberg limits test, and density test were
carried out on the mix material. The chemical composition obtained
for the RHA showed that the total percentage compositions of Fe2O3,
SiO2 and Al2O3 were found to be above 70% (class “F” pozzolan)
which qualifies it as a very good pozzolan. The coefficient of
uniformity (Cu) was 8 and coefficient of curvature (Cc) was 2 for the
soil sample. The Plasticity Index (PI) for the 0, 2, 4, 6, 8. 10% was
21.0, 18.8, 16.7, 14.4, 12.4 and 10.7 respectively. The work
concluded that RHA can be effectively used in hydraulic barriers and
as a stabilizing agent in soil stabilization.
Abstract: This paper presents the result of an experimental
investigation regarding the use of Fe2O3 nanoparticles added to
kerosene as a working fluid, under magnetic field for Copper
Oscillating Heat pipe with inclination angle of 0°(horizontal), 15°,
30°,45°, 60°,75° and 90° (vertical). The following were examined;
measure the temperature distribution and heat transfer rate on
Oscillating Heat Pipe (OHP), with magnetic field under different
angles. Results showed that the addition of Fe2O3 nanoparticles under
magnetic field improved thermal performance of OHP especially in
75°.
Abstract: Thermal enhancement of a single mini channel in
Proton Exchange Membrane Fuel Cell (PEMFC) cooling plate is
numerically investigated. In this study, low concentration of Al2O3 in
Water - Ethylene Glycol mixtures is used as coolant in single channel
of carbon graphite plate to mimic the mini channels in PEMFC
cooling plate. A steady and incompressible flow with constant heat
flux is assumed in the channel of 1mm x 5mm x 100mm. Nano
particle of Al2O3 used ranges from 0.1, 0.3 and 0.5 vol %
concentration and then dispersed in 60:40 (water: Ethylene Glycol)
mixture. The effect of different flow rates to fluid flow and heat
transfer enhancement in Re number range of 20 to 140 was observed.
The result showed that heat transfer coefficient was improved by
18.11%, 9.86% and 5.37% for 0.5, 0.3 and 0.1 vol. % Al2O3 in 60:40
(water: EG) as compared to base fluid of 60:40 (water: EG). It is also
showed that the higher vol. % concentration of Al2O3 performed
better in term of thermal enhancement but at the expense of higher
pumping power required due to increase in pressure drop
experienced. Maximum additional pumping power of 0.0012W was
required for 0.5 vol % Al2O3 in 60:40 (water: EG) at Re number 140.
Abstract: In this numerical work, mixed convection and entropy
generation of Cu–water nanofluid in a lid-driven square cavity have
been investigated numerically using the Lattice Boltzmann Method.
Horizontal walls of the cavity are adiabatic and vertical walls have
constant temperature but different values. The top wall has been
considered as moving from left to right at a constant speed, U0. The
effects of different parameters such as nanoparticle volume
concentration (0–0.05), Rayleigh number (104–106) and Reynolds
numbers (1, 10 and 100) on the entropy generation, flow and
temperature fields are studied. The results have shown that addition
of nanoparticles to the base fluid affects the entropy generation, flow
pattern and thermal behavior especially at higher Rayleigh and low
Reynolds numbers. For pure fluid as well as nanofluid, the increase
of Reynolds number increases the average Nusselt number and the
total entropy generation, linearly. The maximum entropy generation
occurs in nanofluid at low Rayleigh number and at high Reynolds
number. The minimum entropy generation occurs in pure fluid at low
Rayleigh and Reynolds numbers. Also at higher Reynolds number,
the effect of Cu nanoparticles on enhancement of heat transfer was
decreased because the effect of lid-driven cavity was increased. The
present results are validated by favorable comparisons with
previously published results. The results of the problem are presented
in graphical and tabular forms and discussed.
Abstract: We investigated ecotoxicity and performed experiment
for removing ZnO nanoparticles in water. Short term exposure of
hatching test using fertilized eggs (O. latipes) showed deformity in
5ppm of ZnO nanoparticles solution. And in 10ppm ZnO nanoparticles
solution delayed hatching was observed. Hereine, chemical
precipitation method was suggested for removing ZnO nanoparticles
in water. The precipitated ZnO nanoparticles showed the form of ZnS
after addition of Na2S, and the form of Zn3(PO4)2 for Na2HPO4. The
removal efficiency of ZnO nanoparticles in water was closed to 100%
for two cases. In ecotoxicity evaluation of as-precipitated ZnS and
Zn3(PO4)2, they did not cause any acute toxicity for D. magna. It is
noted that this precipitation treatment of ZnO is effective to reduce the
potential cytotoxicity.
Abstract: Biomass treatment through densification is very suitable and helpful technology before its effective energy recovery. Densification process of biomass is significantly influenced by various technological and material variables, which are ultimately reflected on the final solid biofuels quality. The paper deals with the experimental research of the relationship between technological and material variables during densification of fast-growing trees, roundly fast-growing willows. The main goal of presented experimental research is to determine the relationship between compression pressure and raw material particle size from a final briquettes density point of view. Experimental research was realized by single-axis densification. The impact of particle size with interaction of compression pressure and stabilization time on the quality properties of briquettes was determined. These variables interaction affects the final solid biofuels (briquettes) quality. From briquettes production point of view and from densification machines constructions point of view is very important to know about mutual interaction of these variables on final briquettes quality. The experimental findings presented here are showing the importance of mentioned variables during the densification process.
Abstract: In this paper, we present a quantum statistical
mechanical formulation from our recently analytical expressions for
partial-wave transition matrix of a three-particle system. We report
the quantum reactive cross sections for three-body scattering
processes 1+(2,3)→1+(2,3) as well as recombination
1+(2,3)→1+(3,1) between one atom and a weakly-bound dimer. The
analytical expressions of three-particle transition matrices and their
corresponding cross-sections were obtained from the threedimensional
Faddeev equations subjected to the rank-two non-local
separable potentials of the generalized Yamaguchi form. The
equilibrium quantum statistical mechanical properties such partition
function and equation of state as well as non-equilibrium quantum
statistical properties such as transport cross-sections and their
corresponding transport collision integrals were formulated
analytically. This leads to obtain the transport properties, such as
viscosity and diffusion coefficient of a moderate dense gas.
Abstract: The seriously damaged structures during earthquakes
show the need and importance of design of reinforced concrete
structures with high ductility. Reinforced concrete beam-column
joints have an important function in all structures. Under seismic
excitation, the beam column joint region is subjected to horizontal
and vertical shear forces whose magnitude is many times higher than
the adjacent beam and column. Strength and ductility of structures
depends mainly on proper detailing of the reinforcement in beamcolumn
joints and the old structures were found ductility deficient.
DSP materials are obtained by using high quantities of super
plasticizers and high volumes of micro silica. In the case of High
Performance Densified Small Particle Concrete (HPDSPC), since
concrete is dense even at the micro-structure level, tensile strain
would be much higher than that of the conventional SFRC, SIFCON
& SIMCON. This in turn will improve cracking behaviour, ductility
and energy absorption capacity of composites in addition to
durability. The fine fibers used in our mix are 0.3mm diameter and 10
mm which can be easily placed with high percentage. These fibers
easily transfer stresses and act as a composite concrete unit to take up
extremely high loads with high compressive strength. HPDSPC
placed in the beam column joints helps in safety of human life due to
prolonged failure.
Abstract: The aim of this study was to investigate the
photocatalytic activity of polycrystalline phases of bismuth tungstate
of formula Bi2WO6. Polycrystalline samples were elaborated using a
coprecipitation technique followed by a calcination process at
different temperatures (300, 400, 600 and 900°C). The obtained
polycrystalline phases have been characterized by X-ray diffraction
(XRD), scanning electron microscopy (SEM), and transmission
electron microscopy (TEM). Crystal cell parameters and cell volume
depend on elaboration temperature. High-resolution electron
microscopy images and image simulations, associated with X-ray
diffraction data, allowed confirming the lattices and space groups
Pca21. The photocatalytic activity of the as-prepared samples was
studied by irradiating aqueous solutions of Rhodamine B, associated
with Bi2WO6 additives having variable crystallite sizes. The
photocatalytic activity of such bismuth tungstates increased as the
crystallite sizes decreased. The high specific area of the
photocatalytic particles obtained at 300°C seems to condition the
degradation kinetics of RhB.
Abstract: Chitosan polyacrylic acid composite membranes were
prepared by a bulk polymerization method in presence of N, N'-
methylene bisacrylamide (crosslinker) and ammonium persulphate as
initiator. Membranes prepared from this copolymer in presence and
absence of Ag nanoparticles were characterized by measuring
mechanical and physical properties, water up-take and antibacterial
properties. The results obtained indicated that the prepared
membranes have antibacterial properties which increase with adding
Ag nanoparticles.
Abstract: High temperature Fischer-Tropsch synthesis process
use fixed fluidized bed as a reactor. In order to understand the flow
behavior in the fluidized bed better, the research of how the radial
velocity affects the entire flow field is necessary. Laser Doppler
Velocimetry (LDV) was used to study the radial velocity distribution
along the diameter direction of the cross-section of the particle in a
fixed fluidized bed. The velocity in the cross-section is fluctuating
within a small range. The direction of the speed is a random
phenomenon. In addition to r/R is 1, the axial velocity are more than 6
times of the radial velocity, the radial velocity has little impact on the
axial velocity in a fixed fluidized bed.
Abstract: MHD chemically reacting viscous fluid flow towards
a vertical surface with slip and convective boundary conditions has
been conducted. The temperature and the chemical species
concentration of the surface and the velocity of the external flow are
assumed to vary linearly with the distance from the vertical surface.
The governing differential equations are modeled and transformed
into systems of ordinary differential equations, which are then solved
numerically by a shooting method. The effects of various parameters
on the heat and mass transfer characteristics are discussed. Graphical
results are presented for the velocity, temperature, and concentration
profiles whilst the skin-friction coefficient and the rate of heat and
mass transfers near the surface are presented in tables and discussed.
The results revealed that increasing the strength of the magnetic field
increases the skin-friction coefficient and the rate of heat and mass
transfers toward the surface. The velocity profiles are increased
towards the surface due to the presence of the Lorenz force, which
attracts the fluid particles near the surface. The rate of chemical
reaction is seen to decrease the concentration boundary layer near the
surface due to the destructive chemical reaction occurring near the
surface.
Abstract: Carefully scheduling the operations of pumps can be
resulted to significant energy savings. Schedules can be defined
either implicit, in terms of other elements of the network such as tank
levels, or explicit by specifying the time during which each pump is
on/off. In this study, two new explicit representations based on timecontrolled
triggers were analyzed, where the maximum number of
pump switches was established beforehand, and the schedule may
contain fewer switches than the maximum. The optimal operation of
pumping stations was determined using a Jumping Particle Swarm
Optimization (JPSO) algorithm to achieve the minimum energy cost.
The model integrates JPSO optimizer and EPANET hydraulic
network solver. The optimal pump operation schedule of VanZyl
water distribution system was determined using the proposed model
and compared with those from Genetic and Ant Colony algorithms.
The results indicate that the proposed model utilizing the JPSO
algorithm is a versatile management model for the operation of realworld
water distribution system.