Abstract: A conjugate heat transfer for steady two-dimensional
mixed convection with magnetic hydrodynamic (MHD) flow of an
incompressible quiescent fluid over an unsteady thermal forming
stretching sheet has been studied. A parameter, M, which is used to
represent the dominance of the magnetic effect has been presented in
governing equations. The similar transformation and an implicit
finite-difference method have been used to analyze the present
problem. The numerical solutions of the flow velocity distributions,
temperature profiles, the wall unknown values of f''(0) and '(θ (0) for
calculating the heat transfer of the similar boundary-layer flow are
carried out as functions of the unsteadiness parameter (S), the Prandtl
number (Pr), the space-dependent parameter (A) and
temperature-dependent parameter (B) for heat source/sink and the
magnetic parameter (M). The effects of these parameters have also
discussed. At the results, it will produce greater heat transfer effect
with a larger Pr and M, S, A, B will reduce heat transfer effects. At
last, conjugate heat transfer for the free convection with a larger G has
a good heat transfer effect better than a smaller G=0.
Abstract: This paper proposes a novel solution for optimizing
the size and communication overhead of a distributed multiagent
system without compromising the performance. The proposed approach
addresses the challenges of scalability especially when the
multiagent system is large. A modified spectral clustering technique
is used to partition a large network into logically related clusters.
Agents are assigned to monitor dedicated clusters rather than monitor
each device or node. The proposed scalable multiagent system is
implemented using JADE (Java Agent Development Environment)
for a large power system. The performance of the proposed topologyindependent
decentralized multiagent system and the scalable multiagent
system is compared by comprehensively simulating different
fault scenarios. The time taken for reconfiguration, the overall computational
complexity, and the communication overhead incurred are
computed. The results of these simulations show that the proposed
scalable multiagent system uses fewer agents efficiently, makes faster
decisions to reconfigure when a fault occurs, and incurs significantly
less communication overhead.
Abstract: Proteins levels produced by bacteria may be increased
in stressful surroundings, such as in the presence of antibiotics. It
appears that many antimicrobial agents or antibiotics, when used at
low concentrations, have in common the ability to activate or repress
gene transcription, which is distinct from their inhibitory effect.
There have been comparatively few studies on the potential of
antibiotics or natural compounds in nature as a specific chemical
signal that can trigger a variety of biological functions. Therefore,
this study was focusing on the effect of essential oils from
Cymbopogon flexuosus and C. nardus in regulating proteins
production by Bacillus subtilis ATCC 21332. The Minimum
Inhibition Concentrations (MICs) of both essential oils on B. subtilis
were determined by using microdilution assay, resulting 0.2% and
1.56% for each C. flexuosus and C. nardus subsequently. The
bacteria were further exposed to each essential oils at concentration
of 0.01XMIC for 2 days. The proteins were then isolated and
analyzed by sodium dodecyl sulfate polyacrylamide gel
electrophoresis (SDS-PAGE). Protein profile showed that a band
with approximate size of 250 kD was appeared for the treated
bacteria with essential oils. Thus, Bacillus subtilis ATCC 21332 in
stressful condition with the presence of essential oils at low
concentration could induce the protein production.
Abstract: Isobaric vapor-liquid equilibrium measurements are reported for the binary mixtures of Mesitylene + 1-Heptanol and Mesitylene + 1-Octanol at 97.3 kPa. The measurements have been performed using a vapor recirculating type (modified Othmer's) equilibrium still. Both the mixtures show positive deviation from ideality. The Mesitylene + 1-Heptanol mixture forms an azeotrope whereas Mesitylene + 1- Octanol form a non – azeotropic mixture. The activity coefficients have been calculated taking into consideration the vapor phase nonideality. The data satisfy the thermodynamic consistency tests of Herington, and Hirata. The activity coefficients have been satisfactorily correlated by means of the Margules, Redlich-Kister, Wilson, Black, and NRTL equations. The activity coefficient values have also been obtained by UNIFAC method.
Abstract: Carbon nanotubes (CNTs) are attractive because of
their excellent chemical durability mechanical strength and electrical
properties. Therefore there is interest in CNTs for not only electrical
and mechanical application, but also biological and medical
application.
In this study, the dispersion power of surfactant-treated multiwalled
carbon nanotubes (MWCNTs) and their effect on the antibacterial
activity were examined. Surfactant was used sodium
dodecyl-benzenesulfonate (SDBS). UV-vis absorbance and
transmission electron microscopy(TEM) were used to characterize the
dispersion of MWCNTs in the aqueous phase, showing that the
surfactant molecules had been adsorbed onto the MWCNTs surface.
The surfactant-treated MWCNTs exhibited antimicrobial activities
to streptococcus mutans. The optical density growth curves and viable
cell number determined by the plating method suggested that the
antimicrobial activity of surfactant-treated MWCNTs was both
concentration and treatment time-dependent.
Abstract: To simulate heating systems in buildings, a research oriented computer code has been developed in Sharif University of Technology in Iran where the climate, existing heating equipment in buildings, consumer behavior and their interactions are considered for simulating energy consumption in conventional systems such as heaters, radiators and fan-coils. In order to validate the computer code, the available data of five buildings was used and the computed consumed energy was compared with the estimated energy extracted from monthly bills. The initial heating system was replaced by the alternative system and the effect of this change was observed on the energy consumption. As a result, the effect of changing heating equipment on energy consumption was investigated in different climates. Changing heater to radiator renders energy conservation up to 50% in all climates and changing radiator to fan-coil decreases energy consumption in climates with cold and dry winter.
Abstract: Many measures have been proposed for machine
translation evaluation (MTE) while little research has been done on
the performance of MTE methods. This paper is an effort for MTE
performance analysis. A general frame is proposed for the description
of the MTE measure and the test suite, including whether the
automatic measure is consistent with human evaluation, whether
different results from various measures or test suites are consistent,
whether the content of the test suite is suitable for performance
evaluation, the degree of difficulty of the test suite and its influence
on the MTE, the relationship of MTE result significance and the size
of the test suite, etc. For a better clarification of the frame, several
experiment results are analyzed relating human evaluation, BLEU
evaluation, and typological MTE. A visualization method is
introduced for better presentation of the results. The study aims for
aid in construction of test suite and method selection in MTE
practice.
Abstract: In this article, we expose our research work in
Human-machine Interaction. The research consists in manipulating
the workspace by eyes. We present some of our results, in particular
the detection of eyes and the mouse actions recognition. Indeed, the
handicaped user becomes able to interact with the machine in a more
intuitive way in diverse applications and contexts. To test our
application we have chooses to work in real time on videos captured
by a camera placed in front of the user.
Abstract: We present linear codes over finite commutative rings
which are not necessarily Frobenius. We treat the notion of syndrome
decoding by using Pontrjagin duality. We also give a version of Delsarte-s
theorem over rings relating trace codes and subring subcodes.
Abstract: Methanol-to-olefins (MTO) coupled with
transformation of coal or natural gas to methanol gives an interesting
and promising way to produce ethylene and propylene. To investigate
solid concentration in gas-solid fluidized bed for methanol-to-olefins
process catalyzed by SAPO-34, a cold model experiment system is
established in this paper. The system comprises a gas distributor in a
300mm internal diameter and 5000mm height acrylic column, the
fiber optic probe system and series of cyclones. The experiments are
carried out at ambient conditions and under different superficial gas
velocity ranging from 0.3930m/s to 0.7860m/s and different initial bed
height ranging from 600mm to 1200mm. The effects of radial
distance, axial distance, superficial gas velocity, initial bed height on
solid concentration in the bed are discussed. The effects of distributor
shape and porosity on solid concentration are also discussed. The
time-averaged solid concentration profiles under different conditions
are obtained.
Abstract: Equations with differentials relating to the inverse of an unknown function rather than to the unknown function itself are solved exactly for some special cases and numerically for the general case. Invertibility combined with differentiability over connected domains forces solutions always to be monotone. Numerical function inversion is key to all solution algorithms which either are of a forward type or a fixed point type considering whole approximate solution functions in each iteration. The given considerations are restricted to ordinary differential equations with inverted functions (ODEIs) of first order. Forward type computations, if applicable, admit consistency of order one and, under an additional accuracy condition, convergence of order one.
Abstract: The present paper discusses the selection of process
parameters for obtaining optimal nanocrystallites size in the CuOZrO2
catalyst. There are some parameters changing the inorganic
structure which have an influence on the role of hydrolysis and
condensation reaction. A statistical design test method is
implemented in order to optimize the experimental conditions of
CuO-ZrO2 nanoparticles preparation. This method is applied for the
experiments and L16 orthogonal array standard. The crystallites size
is considered as an index. This index will be used for the analysis in
the condition where the parameters vary. The effect of pH, H2O/
precursor molar ratio (R), time and temperature of calcination,
chelating agent and alcohol volume are particularity investigated
among all other parameters. In accordance with the results of
Taguchi, it is found that temperature has the greatest impact on the
particle size. The pH and H2O/ precursor molar ratio have low
influences as compared with temperature. The alcohol volume as
well as the time has almost no effect as compared with all other
parameters. Temperature also has an influence on the morphology
and amorphous structure of zirconia. The optimal conditions are
determined by using Taguchi method. The nanocatalyst is studied by
DTA-TG, XRD, EDS, SEM and TEM. The results of this research
indicate that it is possible to vary the structure, morphology and
properties of the sol-gel by controlling the above-mentioned
parameters.
Abstract: In this paper, the telegraph equation is solved numerically by cubic B-spline quasi-interpolation .We obtain the numerical scheme, by using the derivative of the quasi-interpolation to approximate the spatial derivative of the dependent variable and a low order forward difference to approximate the temporal derivative of the dependent variable. The advantage of the resulting scheme is that the algorithm is very simple so it is very easy to implement. The results of numerical experiments are presented, and are compared with analytical solutions by calculating errors L2 and L∞ norms to confirm the good accuracy of the presented scheme.
Abstract: Nanotechnology is the science of creating, using and
manipulating objects which have at least one dimension in range of
0.1 to 100 nanometers. In other words, nanotechnology is
reconstructing a substance using its individual atoms and arranging
them in a way that is desirable for our purpose.
The main reason that nanotechnology has been attracting
attentions is the unique properties that objects show when they are
formed at nano-scale. These differing characteristics that nano-scale
materials show compared to their nature-existing form is both useful
in creating high quality products and dangerous when being in
contact with body or spread in environment.
In order to control and lower the risk of such nano-scale particles,
the main following three topics should be considered:
1) First of all, these materials would cause long term diseases that
may show their effects on body years after being penetrated in human
organs and since this science has become recently developed in
industrial scale not enough information is available about their
hazards on body.
2) The second is that these particles can easily spread out in
environment and remain in air, soil or water for very long time,
besides their high ability to penetrate body skin and causing new
kinds of diseases.
3) The third one is that to protect body and environment against
the danger of these particles, the protective barriers must be finer than
these small objects and such defenses are hard to accomplish.
This paper will review, discuss and assess the risks that human and
environment face as this new science develops at a high rate.
Abstract: The dynamics of Min proteins plays a center role in
accurate cell division. Although the nucleoids may presumably play
an important role in prokaryotic cell division, there is a lack of
models to account for its participation. In this work, we apply the
lattice Boltzmann method to investigate protein oscillation based on a
mesoscopic model that takes into account the nucleoid-s role. We
found that our numerical results are in reasonably good agreement
with the previous experimental results On comparing with the other
computational models without the presence of nucleoids, the
highlight of our finding is that the local densities of MinD and MinE
on the cytoplasmic membrane increases, especially along the cell
width, when the size of the obstacle increases, leading to a more
distinct cap-like structure at the poles. This feature indicated the
realistic pattern and reflected the combination of Min protein
dynamics and nucleoid-s role.
Abstract: Isobaric vapor-liquid equilibrium measurements are
reported for binary mixture of 2-Methyltetrahydrofuran and Cumene
at 97.3 kPa. The data were obtained using a vapor recirculating type
(modified Othmer's) equilibrium still. The mixture shows slight
negative deviation from ideality. The system does not form an
azeotrope. The experimental data obtained in this study are
thermodynamically consistent according to the Herington test. The
activity coefficients have been satisfactorily correlated by means of
the Margules, and NRTL equations. Excess Gibbs free energy has
been calculated from the experimental data. The values of activity
coefficients have also been obtained by the UNIFAC group
contribution method.
Abstract: The National Bridge Inventory (NBI) includes more
than 600,000 bridges within the United States of America.
Prestressed concrete girder bridges represent one of the most widely
used bridge systems. The majority of these girder bridges were
constructed using 0.5 and 0.6 inch diameter strands. The main
impediments to using larger strand diameters are: 1) lack of prestress
bed capacities, 2) lack of structural knowledge regarding the transfer
and development length of larger strands, and 3) the possibility of
developing wider end zone cracks upon strand release.
This paper presents a study about using 0.7 inch strands in girder
fabrication. Transfer and development length were evaluated, and
girders were fabricated using 0.7 inch strands at different spacings.
Results showed that 0.7 inch strands can be used at 2.0 inch spacing
without violating the AASHTO LRFD Specifications, while attaining
superior performance in shear and flexure.
Abstract: This paper proposes transient angle stability
agents to enhance power system stability. The proposed transient
angle stability agents divided into two strategy agents. The
first strategy agent is a prediction agent that will predict power
system instability. According to the prediction agent-s output,
the second strategy agent, which is a control agent, is automatically
calculating the amount of active power reduction that can
stabilize the system and initiating a control action. The control
action considered is turbine fast valving. The proposed strategies
are applied to a realistic power system, the IEEE 50-
generator system. Results show that the proposed technique can
be used on-line for power system instability prediction and control.
Abstract: In this paper, the test purpose will be to assess
whether or not the accelerated model proposed by Eyring will be able
to translate results for the shape and scale parameters of an
underlying Weibull model, obtained under two accelerating using
conditions, to expected normal using condition results for these
parameters. The product being analyzed is a new type of insulate
fluid, and the accelerating factor is the voltage stresses applied to the
fluid at two different levels (30KV and 40KV). The normal operating
voltage is 25KV. In this case, it was possible to test the insulate fluid
at normal voltage using condition. Both results for the two
parameters of the Weibull model, obtained under normal using
condition and translated from accelerated using conditions to normal
conditions, will be compared to each other to assess the accuracy of
the Eyring model when the accelerating factor is only the voltage
stress.
Abstract: This paper presents the experimental results on effect of applied voltage stress frequency to the occurrence of electrical treeing in 22 kV cross linked polyethylene (XLPE) insulated cable.Hallow disk of XLPE insulating material with thickness 5 mm taken from unused high voltage cable was used as the specimen in this study. Stainless steel needle was inserted gradually into the specimen to give a tip to earth plane electrode separation of 2.50.2 mm at elevated temperature 105-110°C. The specimen was then annealed for 5 minute to minimize any mechanical stress build up around the needle-plane region before it was cooled down to room temperature. Each specimen were subjected to the same applied voltage stress level at 8 kV AC rms, with various frequency, 50, 100, 500, 1000 and 2000 Hz. Initiation time, propagation speed and pattern of electrical treeing were examined in order to study the effect of applied voltage stress frequency. By the experimental results, initial time of visible treeing decreases with increasing in applied voltage frequency. Also, obviously, propagation speed of electrical treeing increases with increasing in applied voltage frequency.Furthermore, two types of electrical treeing, bush-like and branch-like treeing were observed.The experimental results confirmed the effect of voltage stress frequency as well.