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: An experimental investigation is carried out to
establish the performance characteristics of a compression ignition
engine while using cerium oxide nanoparticles as additive in neat
diesel and diesel-biodiesel blends. In the first phase of the
experiments, stability of neat diesel and diesel-biodiesel fuel blends
with the addition of cerium oxide nanoparticles is analyzed. After
series of experiments, it is found that the blends subjected to high
speed blending followed by ultrasonic bath stabilization improves the
stability. In the second phase, performance characteristics are studied
using the stable fuel blends in a single cylinder four stroke engine
coupled with an electrical dynamometer and a data acquisition
system. The cerium oxide acts as an oxygen donating catalyst and
provides oxygen for combustion. The activation energy of cerium
oxide acts to burn off carbon deposits within the engine cylinder at
the wall temperature and prevents the deposition of non-polar
compounds on the cylinder wall results reduction in HC emissions.
The tests revealed that cerium oxide nanoparticles can be used as
additive in diesel and diesel-biodiesel blends to improve complete
combustion of the fuel significantly.
Abstract: The main purpose of this study is static analysis of
two three-degree of freedom parallel mechanisms: 3-RCC and 3-
RRS. Geometry of these mechanisms is expressed and static
equilibrium equations are derived for the whole chains. For these
mechanisms due to the equal number of equations and unknowns, the
solution is as same as 3-RCC mechanism. A mathematical software is
used to solve the equations. In order to prove the results obtained
from solving the equations of mechanisms, the CAD model of these
robots has been simulated and their static is analysed in ADAMS
software. Due to symmetrical geometry of the mechanisms, the force
and external torque acting on the end-effecter have been considered
asymmetric to prove the generality of the solution method. Finally,
the results of both softwares, for both mechanisms are extracted and
compared as graphs. The good achieved comparison between the
results indicates the accuracy of the analysis.
Abstract: In this paper a new model for center of motion
creating is proposed. This new method uses cables. So, it is very
useful in robots because it is light and has easy assembling process.
In the robots which need to be in touch with some things this method
is so useful. It will be described in the following. The accuracy of the
idea is proved by two experiments. This system could be used in the
robots which need a fixed point in the contact with some things and
make a circular motion.
Abstract: In order to use bitumen in hot mix asphalt, it must
have specific characteristics. There are some methods to reach these
properties. Using polymer modifiers are one of the methods to
modify the bitumen properties. In this paper the effect of Styrene-
Butadiene-Rubber that is one of the bitumen polymer modifiers on
rheology properties of bitumen is studied. In this regard, the
rheological properties of base bitumen and the modified bitumen with
3, 4, and 5 percent of Styrene-Butadiene-Rubber (SBR) were
analysed. The results show that bitumen modified with 5 percent of
SBR has the best performance than the other samples.
Abstract: Many industrial materials like magnets need to be
tested for the radiation environment expected at linear colliders (LC)
where the accelerator and detectors will be subjected to large
influences of beta, neutron and gamma’s over their life Gamma
irradiation of the permanent sample magnets using a 60Co source was
investigated up to an absorbed dose of 700Mrad shows a negligible
effect on some magnetic properties of Nd-Fe-B. In this work it has
been tried to investigate the change of some important properties of
Barium hexa ferrite. Results showed little decreases of magnetic
properties at doses rang of 0.5 to 2.5 Mrad. But at the gamma
irradiation dose up to 10 Mrad it is showed a few increase of
properties. Also study of gamma irradiation of Nd-Fe-B showed
considerably increase of magnetic properties.
Abstract: In this research numerical simulations are performed,
using the multi-relaxation-time lattice Boltzmann method, in the
range 3 ≤ β = w[d] ≤ 30 at Re = 100, 200 and 300, where β the
blockage ratio, w is the equispaced distance between centers of
cylinders, d is the diameter of the cylinder and Re is the Reynolds
number, respectively. Special attention is paid to the effect of the
equispaced distance between centers of cylinders. Visualization of
the vorticity contour visualization are presented for some simulation
showing the flow dynamics and patterns for blockage effect. Results
show that the drag and mean drag coefficients, and Strouhal number,
in general, decrease with the increase of β for fixed Re. It is found
that the decreasing rate of drag and mean drag coefficients and
Strouhal number is more distinct in the range 3 ≤ β ≤ 15. We found
that when β > 15, the blockage effect almost diminishes. Our results
further indicate that the drag and mean drag coefficients, peak value
of the lift coefficient, root-mean-square value of the lift and drag
coefficients and the ratio between lift and drag coefficients decrease
with the increase of Re. The results indicate that symmetry boundary
condition have more blockage effect as compared to periodic
boundary condition.
Abstract: The California Bearing Ratio (CBR) has been
acknowledged as an important parameter to characterize the bearing
capacity of earth structures, such as earth dams, road embankments,
airport runways, bridge abutments and pavements. Technically, the
CBR test can be carried out in the laboratory or in the field. The CBR
test is time-consuming and is infrequently performed due to the
equipment needed and the fact that the field moisture content keeps
changing over time. Over the years, many correlations have been
developed for the prediction of CBR by various researchers,
including the dynamic cone penetrometer, undrained shear strength
and Clegg impact hammer. This paper reports and discusses some of
the results from a study on the prediction of CBR. In the current
study, the CBR test was performed in the laboratory on some finegrained
subgrade soils collected from various locations in Victoria.
Based on the test results, a satisfactory empirical correlation was
found between the CBR and the physical properties of the
experimental soils.
Abstract: Background and aim: It has not been well studied
whether fentanyl-thiopental (FT) is effective and safe for PSA in
orthopedic procedures in Emergency Department (ED). The aim of
this trial was to evaluate the effectiveness of intravenous FT versus
fentanyl-midazolam (FM) in patients who suffered from shoulder
dislocation or distal radial fracture-dislocation.
Methods: In this randomized double-blinded study, Seventy-six
eligible patients were entered the study and randomly received
intravenous FT or FM. The success rate, onset of action and recovery
time, pain score, physicians’ satisfaction and adverse events were
assessed and recorded by treating emergency physicians. The
statistical analysis was intention to treat.
Results: The success rate after administrating loading dose in FT
group was significantly higher than FM group (71.7% vs. 48.9%,
p=0.04); however, the ultimate unsuccessful rate after 3 doses of
drugs in the FT group was higher than the FM group (3 to 1) but it
did not reach to significant level (p=0.61). Despite near equal onset
of action time in two study group (P=0.464), the recovery period in
patients receiving FT was markedly shorter than FM group
(P
Abstract: Examining existing experimental results for shallow
rigid foundations subjected to vertical centric load (N), accompanied
or not with a bending moment (M), two main non-linear mechanisms
governing the cyclic response of the soil-foundation system can be
distinguished: foundation uplift and soil yielding. A soil-foundation
failure limit, is defined as a domain of resistance in the two
dimensional (2D) load space (N, M) inside of which lie all the
admissible combinations of loads; these latter correspond to a pure
elastic, non-linear elastic or plastic behavior of the soil-foundation
system, while the points lying on the failure limit correspond to a
combination of loads leading to a failure of the soil-foundation
system. In this study, the proposed resistance domain is constructed
analytically based on mechanics. Original elastic limit, uplift
initiation limit and iso-uplift limits are constructed inside this
domain. These limits give a prediction of the mechanisms activated
for each combination of loads applied to the foundation. A
comparison of the proposed failure limit with experimental tests
existing in the literature shows interesting results. Also, the
developed uplift initiation limit and iso-uplift curves are confronted
with others already proposed in the literature and widely used due to
the absence of other alternatives, and remarkable differences are
noted, showing evident errors in the past proposals and relevant
accuracy for those given in the present work.
Abstract: In order to investigate the effect of Plant Growth
Promoting Rhizobacteria (PGPR) and rhizobium bacteria on grain
yield and some agronomic traits of mungbean (Vigna radiate L.), an
experiment was carried out based on randomized complete block
design with three replications in Malekshahi, Ilam province, Iran
during 2012-2013 cropping season. Experimental treatments
consisted of control treatment, inoculation with rhizobium bacteria,
rhizobium bacteria and Azotobacter, rhizobium bacteria and
Azospirillum, rhizobium bacteria and Pseudomonas, rhizobium
bacteria, Azotobacter and Azospirillum, rhizobium bacteria,
Azotobacter and Pseudomonas, rhizobium bacteria, Azospirillum and
Pseudomonas and rhizobium bacteria, Azotobacter, Azospirillum and
Pseudomonas. The results showed that the effect of PGPR and
rhizobium bacteria were significant affect on grain and its
components in mungbean plant. Grain yield significantly increased
by PGPR and rhizobium bacteria, so that the maximum grain yield
was obtained from rhizobium bacteria + Azospirillum +
Pseudomonas with the amount of 2287 kg.ha-1 as compared to
control treatment. Excessive application of chemical fertilizers causes
environmental and economic problems. That is, the overfertilization
of P and N leads to pollution due to soil erosion and runoff water, so
the use of PGPR and rhizobium bacteria can be justified due to
reduce input costs, increase in grain yield and environmental friendly.
Abstract: The generalized wave equation models various
problems in sciences and engineering. In this paper, a new three-time
level implicit approach based on cubic trigonometric B-spline for the
approximate solution of wave equation is developed. The usual finite
difference approach is used to discretize the time derivative while
cubic trigonometric B-spline is applied as an interpolating function in
the space dimension. Von Neumann stability analysis is used to
analyze the proposed method. Two problems are discussed to exhibit
the feasibility and capability of the method. The absolute errors and
maximum error are computed to assess the performance of the
proposed method. The results were found to be in good agreement
with known solutions and with existing schemes in literature.
Abstract: A new algorithm based on the lattice Boltzmann method (LBM) is proposed as a potential solver for one-dimensional heat and mass transfer for isothermal carbonization of wood particles. To check the validity of this algorithm, the LBM results have been compared with the published data and a good agreement is obtained. Then, the model is used to study the effect of reactor temperature and particle size on the evolution of the local temperature and mass loss inside the wood particle.
Abstract: Accurate Short Term Load Forecasting (STLF) is essential for a variety of decision making processes. However, forecasting accuracy can drop due to the presence of uncertainty in the operation of energy systems or unexpected behavior of exogenous variables. Interval Type 2 Fuzzy Logic System (IT2 FLS), with additional degrees of freedom, gives an excellent tool for handling uncertainties and it improved the prediction accuracy. The training data used in this study covers the period from January 1, 2012 to February 1, 2012 for winter season and the period from July 1, 2012 to August 1, 2012 for summer season. The actual load forecasting period starts from January 22, till 28, 2012 for winter model and from July 22 till 28, 2012 for summer model. The real data for Iraqi power system which belongs to the Ministry of Electricity.
Abstract: A numerical study based on the Lattice Boltzmann Method (LBM) is proposed to solve one, two and three dimensional heat and mass transfer for isothermal carbonization of thick wood particles. To check the validity of the proposed model, computational results have been compared with the published data and a good agreement is obtained. Then, the model is used to study the effect of reactor temperature and thermal boundary conditions, on the evolution of the local temperature and the mass distributions of the wood particle during carbonization
Abstract: The radiative heat transfer problem is investigated numerically for 2D complex geometry biomass pyrolysis reactor composed of two pyrolysis chambers and a heat recuperator. The fumes are a mixture of carbon dioxide and water vapor charged with absorbing and scattering particles and soot. In order to increase gases residence time and heat transfer, the heat recuperator is provided with many inclined, vertical, horizontal, diffuse and grey baffles of finite thickness and has a complex geometry. The Finite Volume Method (FVM) is applied to study radiative heat transfer. The blocked-off region procedure is used to treat the geometrical irregularities. Eight cases are considered in order to demonstrate the effect of adding baffles on the walls of the heat recuperator and on the walls of the pyrolysis rooms then choose the best case giving the maximum heat flux transferred to the biomass in the pyrolysis chambers. Ray effect due to the presence of baffles is studied and demonstrated to have a crucial effect on radiative heat flux on the walls of the pyrolysis rooms. Shadow effect caused by the presence of the baffles is also studied. The non grey radiative heat transfer is studied for the real existent configuration. The Weighted Sum of The Grey Gases (WSGG) Model of Kim and Song is used as non grey model. The effect of soot volumetric fraction on the non grey radiative heat flux is investigated and discussed.
Abstract: The objective of this work is to use the Fire Dynamics Simulator (FDS) to investigate the behavior of a kerosene small-scale fire. FDS is a Computational Fluid Dynamics (CFD) tool developed specifically for fire applications. Throughout its development, FDS is used for the resolution of practical problems in fire protection engineering. At the same time FDS is used to study fundamental fire dynamics and combustion. Predictions are based on Large Eddy Simulation (LES) with a Smagorinsky turbulence model. LES directly computes the large-scale eddies and the sub-grid scale dissipative processes are modeled. This technique is the default turbulence model which was used in this study. The validation of the numerical prediction is done using a direct comparison of combustion output variables to experimental measurements. Effect of the mesh size on the temperature evolutions is investigated and optimum grid size is suggested. Effect of width openings is investigated. Temperature distribution and species flow are presented for different operating conditions. The effect of the composition of the used fuel on atmospheric pollution is also a focus point within this work. Good predictions are obtained where the size of the computational cells within the fire compartment is less than 1/10th of the characteristic fire diameter.
Abstract: Storage tank farms are essential industrial facilities to accumulate oil, petrochemicals and gaseous products. Since tank farms contain huge mass of fuel and hazardous materials, they are always targets of serious accidents such as fire, explosion, spill and toxic release which may cause severe impacts on human health, environmental and properties.
Although having a safe layout is not able to prevent initiating accidents, however it effectively controls and reduces the adverse impact of such accidents.
The aim of this paper is to determine the optimal layout for a storage tank contains different type of hydrocarbon fuels. A quantitative risk assessment is carried out on a selected tank farm in Jaipur, India, with particular attention given to both the consequence modeling and the overall risk assessment using PHAST Software. Various designs of tank layouts are examined taking into consideration several issues of plant operations and maintenance. In all stages of the work, standard guidelines specified by the industry are considered and recommendations are substantiated with simulation results and risk quantification.
Abstract: In economical evaluation literature, although the combination of some variables such as repair and maintenance costs and accumulated use hours has been widely considered in determining of optimum life for tractor, no investigation has indicated the influence of failure rate on repair and maintenance costs. In this study, the owners of three hundred tractors, which include Massey Ferguson, John Deere and Universal, were interviewed, from five regions of Khouzestan Province. A regression model was used to predict the tractors annual repair and maintenance costs based on failure rate. Results showed that the maximum percentage of annual repair and maintenance costs occurred in engine parts for MF285, JD3140 and U650 tractors while these costs for tire, ring, ball bearing and operator seat were higher compared to other MF399 tractor systems. According to the results of the regression, the failure rate increase would lead to annual repair and maintenance costs increase for all tractors. But, of all the tractors, repair and maintenance costs of JD3140 tractors extremely affected by the failure rate increase.
Abstract: Thermal radiation plays a very important role in the heat transfer combination through the various components of the SOFC fuel cell operating at high temperatures. Lattice Boltzmann method is used for treating conduction-radiation heat transfer in the electrolyte. The thermal radiation heat transfer is coupled to the overall energy conservation equations through the divergence of the local radiative flux. The equation of energy in one dimension is numerically resolved by using the Lattice Boltzmann method. A computing program (FORTRAN) is developed locally for this purpose in order to obtain fields of temperature in every element of the cell. The parameters investigated are: functioning temperature, cell voltages and electrolyte thickness. The results show that the radiation effect increases with increasing the electrolyte thickness, also increases with increasing the functioning temperature and decreases with the increase of the voltage of the cell.