Abstract: The convective heat and mass transfer in nanofluid
flow through a porous media due to a permeable stretching sheet with
magnetic field, viscous dissipation, chemical reaction and Soret
effects are numerically investigated. Two types of nanofluids, namely
Cu-water and Ag-water were studied. The governing boundary layer
equations are formulated and reduced to a set of ordinary differential
equations using similarity transformations and then solved
numerically using the Keller box method. Numerical results are
obtained for the skin friction coefficient, Nusselt number and
Sherwood number as well as for the velocity, temperature and
concentration profiles for selected values of the governing
parameters. Excellent validation of the present numerical results has
been achieved with the earlier linearly stretching sheet problems in
the literature.
Abstract: A model was constructed to predict the amount of
solar radiation that will make contact with the surface of the earth in
a given location an hour into the future. This project was supported
by the Southern Company to determine at what specific times during
a given day of the year solar panels could be relied upon to produce
energy in sufficient quantities. Due to their ability as universal
function approximators, an artificial neural network was used to
estimate the nonlinear pattern of solar radiation, which utilized
measurements of weather conditions collected at the Griffin, Georgia
weather station as inputs. A number of network configurations and
training strategies were utilized, though a multilayer perceptron with
a variety of hidden nodes trained with the resilient propagation
algorithm consistently yielded the most accurate predictions. In
addition, a modeled direct normal irradiance field and adjacent
weather station data were used to bolster prediction accuracy. In later
trials, the solar radiation field was preprocessed with a discrete
wavelet transform with the aim of removing noise from the
measurements. The current model provides predictions of solar
radiation with a mean square error of 0.0042, though ongoing efforts
are being made to further improve the model’s accuracy.
Abstract: Dengue outbreaks are affected by biological,
ecological, socio-economic and demographic factors that vary over
time and space. These factors have been examined separately and still
require systematic clarification. The present study aimed to investigate
the spatial-temporal clustering relationships between these factors and
dengue outbreaks in the northern region of Sri Lanka. Remote sensing
(RS) data gathered from a plurality of satellites were used to develop
an index comprising rainfall, humidity and temperature data. RS data
gathered by ALOS/AVNIR-2 were used to detect urbanization, and a
digital land cover map was used to extract land cover information.
Other data on relevant factors and dengue outbreaks were collected
through institutions and extant databases. The analyzed RS data and
databases were integrated into geographic information systems,
enabling temporal analysis, spatial statistical analysis and space-time
clustering analysis. Our present results showed that increases in the
number of the combination of ecological factor and socio-economic
and demographic factors with above the average or the presence
contribute to significantly high rates of space-time dengue clusters.
Abstract: International and domestic environmental law has
evolved quite rapidly in the last few decades. At the international
level the Stockholm and Rio Declarations paved the way for a broad
based consensus of the international community on environmental
issues and principles. At the Domestic level also many states have
incorporated environmental protection in their constitutions and even
more states are doing the same at least in their domestic legislations.
In this process of evolution environmental law has unleashed a
number of novel principles such as; the participatory principle, the
polluter pays principle, the precautionary principle, the intergenerational
and intra-generational principles, the prevention
principle, the sustainable development principle and so on.
Abstract: This paper presents system level CMOS solid-state
nanopore techniques enhancement for speedup next generation
molecular recording and high throughput channels. This discussion
also considers optimum number of base-pair (bp) measurements
through channel as an important role to enhance potential read
accuracy. Effective power consumption estimation offered suitable
range of multi-channel configuration. Nanopore bp extraction model
in statistical method could contribute higher read accuracy with
longer read-length (200 < read-length). Nanopore ionic current
switching with Time Multiplexing (TM) based multichannel readout
system contributed hardware savings.
Abstract: An innovative concept called “Flexy-Energy” is developing at 2iE. This concept aims to produce electricity at lower cost by smartly mix different available energy sources in accordance to the load profile of the region. With a higher solar irradiation and due to the fact that Diesel generator are massively used in sub-Saharan rural areas, PV/Diesel hybrid systems could be a good application of this concept and a good solution to electrify this region, provided they are reliable, cost effective and economically attractive to investors. Presentation of the developed approach is the aims of this paper. The PV/Diesel hybrid system designed consists to produce electricity and/or heat from a coupling between Diesel Diesel generators and PV panels without batteries storage, while ensuring the substitution of gasoil by bio-fuels available in the area where the system will be installed. The optimal design of this system is based on his technical performances; the Life Cycle Cost (LCC) and Levelized Cost of Energy are developed and use as economic criteria. The Net Present Value (NPV), the internal rate of return (IRR) and the discounted payback (DPB) are also evaluated according to dual electricity pricing (in sunny and unsunny hours). The PV/Diesel hybrid system obtained is compared to the standalone Diesel Diesel generators. The approach carried out in this paper has been applied to Siby village in Mali (Latitude 12 ° 23'N 8 ° 20'W) with 295 kWh as daily demand.This approach provides optimal physical characteristics (size of the components, number of component) and dynamical characteristics in real time (number of Diesel generator on, their load rate, fuel specific consumptions, and PV penetration rate) of the system. The system obtained is slightly cost effective; but could be improved with optimized tariffing strategies.
Abstract: This paper reports the worldwide status of building
information modeling (BIM) adoption from the perspectives of the
engagement level, the Hype Cycle model, the technology diffusion
model, and BIM services. An online survey was distributed, and 156
experts from six continents responded. Overall, North America was
the most advanced continent, followed by Oceania and Europe.
Countries in Asia perceived their phase mainly as slope of
enlightenment (mature) in the Hype Cycle model. In the technology
diffusion model, the main BIM-users worldwide were “early majority”
(third phase), but those in the Middle East/Africa and South America
were “early adopters” (second phase). In addition, the more advanced
the country, the more number of BIM services employed in general. In
summary, North America, Europe, Oceania, and Asia were advancing
rapidly toward the mature stage of BIM, whereas the Middle
East/Africa and South America were still in the early phase. The
simple indexes used in this study may be used to track the worldwide
status of BIM adoption in long-term surveys.
Abstract: Generating random numbers are mainly used to create
secret keys or random sequences. It can be carried out by various
techniques. In this paper we present a very simple and efficient
pseudo random number generator (PRNG) based on chaotic maps
and S-Box tables. This technique adopted two main operations one to
generate chaotic values using two logistic maps and the second to
transform them into binary words using random S-Box tables.
The simulation analysis indicates that our PRNG possessing
excellent statistical and cryptographic properties.
Abstract: This paper shortly describes various types of biomass
and a growing number of facilities utilizing the biomass in the Czech
Republic. The considerable part of this paper deals with energy
parameters of the most frequently used types of biomass and results
of their gasification testing. Sixteen most used "Czech" woody plants
and grasses were selected; raw, element and biochemical analyses
were performed and basic calorimetric values, ash composition, and
ash characteristic temperatures were identified. Later, each biofuel
was tested in a fluidized bed gasifier. The essential part of this paper
provides results of the gasification of selected biomass types.
Operating conditions are described in detail with a focus on
individual fuels properties. Gas composition and impurities content
are also identified. In terms of operating conditions and gas quality,
the essential difference occurred mainly between woody plants and
grasses. The woody plants were evaluated as more suitable fuels for
fluidized bed gasifiers. Testing results significantly help with a
decision-making process regarding suitability of energy plants for
growing and with a selection of optimal biomass-treatment
technology.
Abstract: To study the effect of the cross direction in bead
wheat, three hybrid combinations (Babyle 113, Iratome), (Sawa,
Tamose2) and (Al Hashymya, Al Iraq) were tested for plant height,
spike and awn length, number of grains per spike, 1000-grain weight,
number of tillers/m and grain yield. The results revealed that the
direction of the crosses significantly effect on the number of
grains/spike, number of tillers/m and grain yields. Grain yield was
positively and significantly correlated with 1000-grain weight,
number of grains per spike and tillers. Depend on the results of
heritability and genetic advance it was suggested that 1000-grain
weight, number of grains per spike and tillers should be given
emphasis for future wheat yield improvement programs.
Abstract: Considering palm oil as non-drying oil owing to its
low iodine value, an attempt was taken to increase the unsaturation in
the fatty acid chains of palm oil for the preparation of alkyds. To
increase the unsaturation in the palm oil, sulphuric acid (SA) and
para-toluene sulphonic acid (PTSA) was used prior to alcoholysis for
the dehydration process. The iodine number of the oil samples was
checked for the unsaturation measurement by Wijs method. Alkyd
resin was prepared using the dehydrated palm oil by following
alcoholysis and esterification reaction. To improve the film properties
0.5wt.% multi-wall carbon nano tubes (MWCNTs) were used to
manufacture polymeric film. The properties of the resins were
characterized by various physico-chemical properties such as density,
viscosity, iodine value, saponification value, etc. Structural
elucidation was confirmed by Fourier transform of infrared
spectroscopy and proton nuclear magnetic resonance; surfaces of the
films were examined by field-emission scanning electron microscope.
In addition, pencil hardness and chemical resistivity was also
measured by using standard methods. The effect of enhancement of
the unsaturation in the fatty acid chain found significant and
motivational. The resin prepared with dehydrated palm oil showed
improved properties regarding hardness and chemical resistivity
testing. The incorporation of MWCNTs enhanced the thermal
stability and hardness of the films as well.
Abstract: Information technology and information systems are
currently at a tipping point. The digital age fundamentally transforms
a large number of industries in the ways they work. Lines between
business and technology blur. Researchers have acknowledged that
this is the time in which the IT/IS organisation needs to re-strategize
itself. In this paper, the author provides a structured review of the IS
and organisation design literature addressing the question of how the
digital age changes the design categories of an IT/IS organisation
design. The findings show that most papers just analyse single
aspects of either IT/IS relevant information or generic organisation
design elements but miss a holistic ‘big-picture’ onto an IT/IS
organisation design. This paper creates a holistic IT/IS organisation
design framework bringing together the IS research strand, the digital
strand and the generic organisation design strand. The research
identified four IT/IS organisation design categories (strategy,
structure, processes and people) and discusses the importance of two
additional categories (sourcing and governance). The authors findings
point to a first anchor point from which further research needs to be
conducted to develop a holistic IT/IS organisation design framework.
Abstract: This paper reports the numerical simulation of doublediffusive
natural convection flows within a horizontal annular filled
with a saturated porous medium. The analysis concerns the influence
of the different parameters governing the problem, namely, the
Rayleigh number Ra, the Lewis number Le and the buoyancy ratio N,
on the heat and mass transfer and on the flow structure, in the case of
a fixed radius ratio R = 2. The numerical model used for the
discretization of the dimensionless equations governing the problem
is based on the finite difference method, using the ADI scheme. The
study is focused on steady-state solutions in the cooperation situation.
Abstract: The paper presents a thermodynamic cycle analysis
for three turboshaft engines. The first cycle is a Brayton cycle,
describing the evolution of a classical turboshaft, based on the
Klimov TV2 engine. The other four cycles aim at approaching an
Ericsson cycle, by replacing the Brayton cycle adiabatic expansion in
the turbine by quasi-isothermal expansion. The maximum quasi-
Ericsson cycles temperature is set to a lower value than the maximum
Brayton cycle temperature, equal to the Brayton cycle power turbine
inlet temperature, in order to decrease the engine NOx emissions.
Also, the power/expansion ratio distribution over the stages of the gas
generator turbine is maintained the same. In two of the considered
quasi-Ericsson cycles, the efficiencies of the gas generator turbine, as
well as the power/expansion ratio distribution over the stages of the
gas generator turbine are maintained the same as for the reference
case, while for the other two cases, the efficiencies are increased in
order to obtain the same shaft power as in the reference case. For the
two cases respecting the first condition, both the shaft power and the
thermodynamic efficiency of the engine decrease, while for the other
two, the power and efficiency are maintained, as a result of assuming
new, more efficient gas generator turbines.
Abstract: The Algeria by its location offers a rich and diverse
vegetation. A large number of aromatic and medicinal plants grow
spontaneously. The interest in these plants has continued to grow in
recent years. Their particular properties due to the essential oil
fraction can be utilized to treat microbial infections. To this end, and
in the context of the valuation of the Algerian flora, we became
interested in the species of the family Lamiaceae which is one of the
most used as a global source of spices. The plant on which we have
based our choice is a species of sage "Salvia officinalis" from the
Isser localized region within the province of Boumerdes. This work
focuses on the study of the antimicrobial activity of essential oil
extracted from the leaves of Salvia officinalis. The extraction is
carried out by essential oil hydrodistillation and reveals a yield of
1.06℅. The study of the antimicrobial activity of the essential oil by
the method of at aromatogramme shown that Gram positive bacteria
are most susceptible (Staphylococcus aureus and Bacillus subtilis)
with a strong inhibition of growth. The yeast Candida albicans
fungus Aspergillus niger and have shown moderately sensitive.
Abstract: Electronic Word-Of-Mouth (eWOM) communities
represent today an important source of information in which more
and more customers base their purchasing decisions. They include
thousands of reviews concerning very different products and services
posted by many individuals geographically distributed all over the
world. Due to their massive audience, eWOM communities can help
users to find the product they are looking for even if they are less
popular or rare. This is known as the long tail effect, which leads to a
larger number of lower-selling niche products. This paper analyzes
the long tail effect in a well-known eWOM community and defines a
tool for finding niche products unavailable through conventional
channels.
Abstract: Two finite element (FEM) models are presented in
this paper to address the random nature of the response of glued
timber structures made of wood segments with variable elastic
moduli evaluated from 3600 indentation measurements. This total
database served to create the same number of ensembles as was the
number of segments in the tested beam. Statistics of these ensembles
were then assigned to given segments of beams and the Latin
Hypercube Sampling (LHS) method was called to perform 100
simulations resulting into the ensemble of 100 deflections subjected
to statistical evaluation. Here, a detailed geometrical arrangement of
individual segments in the laminated beam was considered in the
construction of two-dimensional FEM model subjected to in fourpoint
bending to comply with the laboratory tests. Since laboratory
measurements of local elastic moduli may in general suffer from a
significant experimental error, it appears advantageous to exploit the
full scale measurements of timber beams, i.e. deflections, to improve
their prior distributions with the help of the Bayesian statistical
method. This, however, requires an efficient computational model
when simulating the laboratory tests numerically. To this end, a
simplified model based on Mindlin’s beam theory was established.
The improved posterior distributions show that the most significant
change of the Young’s modulus distribution takes place in laminae in
the most strained zones, i.e. in the top and bottom layers within the
beam center region. Posterior distributions of moduli of elasticity
were subsequently utilized in the 2D FEM model and compared with
the original simulations.
Abstract: The thermal control in many systems is widely
accomplished applying mixed convection process due to its low cost,
reliability and easy maintenance. Typical applications include the
aircraft electronic equipment, rotating-disc heat exchangers, turbo
machinery, and nuclear reactors, etc. Natural convection in an inclined
square enclosure heated via wall heater has been studied numerically.
Finite volume method is used for solving momentum and energy
equations in the form of stream function–vorticity. The right and left
walls are kept at a constant temperature, while the other parts are
adiabatic. The range of the inclination angle covers a whole revolution.
The method is validated for a vertical cavity. A general power law
dependence of the Nusselt number with respect to the Rayleigh
number with the coefficient and exponent as functions of the
inclination angle is presented. For a fixed Rayleigh number, the
inclination angle increases or decreases is found.
Abstract: This paper proposes five level diode clamped Z source
Inverter. The existing PWM techniques used for ZSI are restricted for
two level. The two level Z Source Inverter have high harmonic
distortions which effects the performance of the grid connected PV
system. To improve the performance of the system the number of
voltage levels in the output waveform need to be increased. This
paper presents comparative analysis of a five level diode clamped Z
source Inverter with different carrier based Modified Pulse Width
Modulation techniques. The parameters considered for comparison
are output voltage, voltage gain, voltage stress across switch and total
harmonic distortion when powered by same DC supply. Analytical
results are verified using MATLAB.
Abstract: The check-in area of airport terminal is one of the
busiest sections at airports at certain periods. The passengers are
subjected to queues and delays during the check-in process. These
delays and queues are due to constraints in the capacity of service
facilities. In this project, the airport terminal is decomposed into
several check-in areas. The airport check-in scheduling problem
requires both a deterministic (integer programming) and stochastic
(simulation) approach. Integer programming formulations are
provided to minimize the total number of counters in each check-in
area under the realistic constraint that counters for one and the same
flight should be adjacent and the desired number of counters
remaining in each area should be fixed during check-in operations.
By using simulation, the airport system can be modeled to study the
effects of various parameters such as number of passengers on a
flight and check-in counter opening and closing time.