Abstract: The aim of this paper is to understand emerging
learning conditions, when a visual analytics is implemented and used
in K 12 (education). To date, little attention has been paid to the role
visual analytics (digital media and technology that highlight visual
data communication in order to support analytical tasks) can play in
education, and to the extent to which these tools can process
actionable data for young students. This study was conducted in three
public K 12 schools, in four social science classes with students aged
10 to 13 years, over a period of two to four weeks at each school.
Empirical data were generated using video observations and analyzed
with help of metaphors within Actor-network theory (ANT). The
learning conditions are found to be distinguished by broad
complexity, characterized by four dimensions. These emerge from
the actors’ deeply intertwined relations in the activities. The paper
argues in relation to the found dimensions that novel approaches to
teaching and learning could benefit students’ knowledge building as
they work with visual analytics, analyzing visualized data.
Abstract: In recent years parasitic antenna play major role in
MIMO systems because of their gain and spectral efficiency. In this
paper, single RF chain MIMO transmitter is designed using
reconfigurable parasitic antenna. The Spatial Modulation (SM) is a
recently proposed scheme in MIMO scenario which activates only
one antenna at a time. The SM entirely avoids ICI and IAS, and only
requires a single RF chain at the transmitter. This would switch ON a
single transmit-antenna for data transmission while all the other
antennas are kept silent. The purpose of the parasitic elements is to
change the radiation pattern of the radio waves which is emitted from
the driven element and directing them in one direction and hence
introduces transmit diversity. Diode is connect between the patch and
ground by changing its state (ON and OFF) the parasitic element act
as reflector and director and also capable of steering azimuth and
elevation angle. This can be achieved by changing the input
impedance of each parasitic element through single RF chain. The
switching of diode would select the single parasitic antenna for
spatial modulation. This antenna is expected to achieve maximum
gain with desired efficiency.
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: Modeling and forecasting dynamics of rainfall
occurrences constitute one of the major topics, which have been
largely treated by statisticians, hydrologists, climatologists and many
other groups of scientists. In the same issue, we propose, in the
present paper, a new hybrid method, which combines Extreme
Values and fractal theories. We illustrate the use of our methodology
for transformed Emberger Index series, constructed basing on data
recorded in Oujda (Morocco).
The index is treated at first by Peaks Over Threshold (POT)
approach, to identify excess observations over an optimal threshold u.
In the second step, we consider the resulting excess as a fractal object
included in one dimensional space of time. We identify fractal
dimension by the box counting. We discuss the prospect descriptions
of rainfall data sets under Generalized Pareto Distribution, assured by
Extreme Values Theory (EVT). We show that, despite of the
appropriateness of return periods given by POT approach, the
introduction of fractal dimension provides accurate interpretation
results, which can ameliorate apprehension of rainfall occurrences.
Abstract: In a multi-cultural learning context, where ties are
weak and dynamic, combining qualitative with quantitative research
methods may be more effective. Such a combination may also allow
us to answer different types of question, such as about people’s
perception of the network. In this study the use of observation,
interviews and photos were explored as ways of enhancing data from
social network questionnaires. Integrating all of these methods was
found to enhance the quality of data collected and its accuracy, also
providing a richer story of the network dynamics and the factors that
shaped these changes over time.
Abstract: Morphological interaction of porcine cumulus-oocyte
complexes (pCOCs) was investigated on in vitro condition using
electron microscope (SEM and TEM). The totals of 1,923 oocytes
were round in shape, surrounded by Zona pellucida with layer of
cumulus cells ranging between 59.29-202.14 μm in size. They were
classified into intact-, multi-, partial cumulus cell layer oocyte, and
completely denuded oocyte, at the percentage composition of 22.80%
32.70%, 18.60%, and 25.90 % respectively. The pCOCs classified as
intact- and multi cumulus cell layer oocytes were further culturing at
37°C with 5% CO2, 95% air atmosphere and high humidity for 44 h
in M199 with Earle’s salts supplemented with 10% HTFCS, 2.2
mg/mL NaHCO3, 1 M Hepes, 0.25 mM pyruvate, 15 μg/mL porcine
follicle-stimulating hormone, 1 μg/mL LH, 1μg/mL estradiol with
ethanol, and 50 μg/mL gentamycin sulfate. On electron microscope
study, cumulus cells were found to stick their processes to secrete
substance from the sac-shape end into Zona pellucida of the oocyte
and also communicated with the neighboring cells through their
microvilli on the beginning of incubation period. It is believed that
the cumulus cells communicate with the oocyte by inserting the
microvilli through this gap and embedded in the oocyte cytoplasm
before secreting substance, through the sac-shape end of the
microvilli, to inhibit primary oocyte development at the prophase I.
Morphological changes of the complexes were observed after
culturing for 24-44 h. One hundred percentages of the cumulus layers
were expanded and cumulus cells were peeling off from the oocyte
surface. In addition, the round-shape cumulus cells transformed
themselves into either an elongate shape or a columnar shape, and no
communication between cumulus neighboring cells. After 44 h of
incubation time, diameter of oocytes surrounded by cumulus cells
was larger than 0 h incubation. The effect of hormones in culture
medium is exerted by their receptors present in porcine oocyte. It is
likely that all morphological changes of the complexes after hormone
treatment were to allow maturation of the oocyte. This study
demonstrated that the association of hormones in M199 could
promote porcine follicle activation in 44 h in vitro condition. This
culture system should be useful for studying the regulation of early
follicular growth and development, especially because these follicles represent a large source of oocytes that could be used in vitro for cell
technology.
Abstract: Teaching art by digital means is a big challenge for
the majority of teachers of art and design in primary schools, yet it
allows relationships between art, technology and creativity to be
clearly identified. The aim of this article is to present a modern way
of teaching art, using digital tools in the art classroom to improve
creative ability in pupils aged between nine and eleven years. It also
presents a conceptual model for creativity based on digital art. The
model could be useful for pupils interested in learning to draw by
using an e-drawing package, and for teachers who are interested in
teaching modern digital art in order to improve children’s creativity.
By illustrating the strategy of teaching art through technology, this
model may also help education providers to make suitable choices
about which technological approaches are most effective in
enhancing students’ creative ability, and which digital art tools can
benefit children by developing their technical skills. It is also
expected that use of this model will help to develop skills of social
interaction, which may in turn improve intellectual ability.
Abstract: The effect of transition metal doping on Pt/Al2O3
catalyst used in propane dehydrogenation reaction at 500°C was
studied. The preparation methods investigated were sequential
impregnation (Pt followed by the 2nd metal or the 2nd metal followed
by Pt) and co-impregnation. The metal contents of these catalysts
were fixed as the weight ratio of Pt per the 2nd metal of around 0.075.
These catalysts were characterized by N2-physisorption, TPR, COchemisorption
and NH3-TPD. It was found that the impregnated 2nd
metal had an effect upon reducibility of Pt due to its interaction with
transition metal-containing structure. This was in agreement with the
CO-chemisorption result that the presence of Pt metal, which is a
result from Pt species reduction, was decreased. The total acidity of
bimetallic catalysts is decreased but the strong acidity is slightly
increased. It was found that the stability of bimetallic catalysts
prepared by co-impregnation and sequential impregnation where the
2nd metal was impregnated before Pt were better than that of
monometallic catalyst (undoped Pt one) due to the forming of Pt sites
located on the transition metal-oxide modified surface. Among all
preparation methods, the sequential impregnation method- having Pt
impregnated before the 2nd metal gave the worst stability because this
catalyst lacked the modified Pt sites and some fraction of Pt sites was
covered by the 2nd metal.
Abstract: Beta-glucosidase, chitinase, leucine-aminopeptidase, acid phosphomonoesterase and acetate-esterase enzyme activities in
the soils under the impact of metallurgical industrial activity in Lori
marz (district) were investigated. The results of the study showed that
the activities of the investigated enzymes in the soils decreased with increasing distance from the Shamlugh copper mine, the Chochkan
tailings storage facility and the ore transportation road. Statistical
analysis revealed that the activities of the enzymes were positively
correlated (significant) to each other according to the observation
sites which indicated that enzyme activities were affected by the
same anthropogenic factor. The investigations showed that the soils
were polluted with heavy metals (Cu, Pb, As, Co, Ni, Zn) due to
copper mining activity in this territory. The results of Pearson
correlation analysis revealed a significant negative correlation
between heavy metal pollution degree (Nemerow integrated pollution
index) and soil enzyme activity. All of this indicated that copper
mining activity in this territory causing the heavy metal pollution of
the soils resulted in the inhabitation of the activities of the enzymes
which are considered as biological catalysts to decompose organic
materials and facilitate the cycling of nutrients.
Abstract: This technical contribution treats of a novel approach
to condition-oriented maintenance as elaborated by Collaborative
Research Centre 653 at the Leibniz University in Hanover. The
objective resides in the targeted analysis of information about a
component's lifecycle for maintenance purposes. The information in
question is collected by means of the Collaborative Research Centre's
innovative technologies. This enables preventive maintenance of
components on the basis of their condition. This contribution initially
explains condition-oriented maintenance, before introducing the
Collaborative Research Centre and finally presenting the
methodology for analyzing the information. The current state of
development is described and an outlook provided for expanding the
methodology.
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: Within the framework of this research, the regulatory
documents, which are in force in relation to this industry, were
analyzed. The main attention is turned to their modernization and
necessity of their compliance with European standards.
It is a current issue to direct the efforts of state policy on support
of business by implementing infrastructural projects, as well as by
development of human resources, which may be possible by
supporting the relevant higher and vocational studying-educational
programs.
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: Paraffinic oils were submitted to microbial action. The
microorganisms consisted of bacteria of the genera Pseudomonas sp.
and Bacillus lincheniforms. The alterations in interfacial tension were
determined using a tensometer and applying the hanging drop
technique at room temperature (299 K ±275 K). The alteration in the
constitution of the paraffins was evaluated by means of gas
chromatography. The microbial activity was observed to reduce
interfacial tension by 54 to 78%, as well as consuming the paraffins
C19 to C29 and producing paraffins C36 to C44. The LIFirr technique
made it possible to determine the microbial action quickly.
Abstract: This paper argues nation-building theories that
prioritize democratic governance best explain the successful postindependence
development of Botswana. Three main competing
schools of thought exist regarding the sequencing of policies that
should occur to re-build weakened or failed states. The first posits
that economic development should receive foremost attention, while
democratization and a binding sense of nationalism can wait. A
second group of experts identified constructing a sense of nationalism
among a populace is necessary first, so that the state receives popular
legitimacy and obedience that are prerequisites for development.
Botswana, though, transitioned into a multi-party democracy and
prosperous open economy due to the utilization of traditional
democratic structures, enlightened and accountable leadership, and an
educated technocratic civil service. With these political foundations
already in place when the discovery of diamonds occurred, the
resulting revenues were spent wisely on projects that grew the
economy, improved basic living standards, and attracted foreign
investment. Thus democratization preceded, and therefore provided
an accountable basis for, economic development that might otherwise
have been squandered by greedy and isolated elites to the detriment
of the greater population. Botswana was one of the poorest nations in
the world at the time of its independence in 1966, with little
infrastructure, a dependence on apartheid South Africa for trade, and
a largely subsistence economy. Over the next thirty years, though, its
economy grew the fastest of any nation in the world. The transparent
and judicious use of diamond returns is only a partial explanation, as
the government also pursued economic diversification, mass
education, and rural development in response to public needs.
As nation-building has become a project undertaken by nations
and multilateral agencies such as the United Nations and the North
Atlantic Treaty Organization, Botswana may provide best practices
that others should follow in attempting to reconstruct economically
and politically unstable states.
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: In this paper, we investigate the effect of friendly
jamming power allocation strategies on the achievable average
secrecy rate over a bank of parallel fading wiretap channels.
We investigate the achievable average secrecy rate in parallel
fading wiretap channels subject to Rayleigh and Rician fading.
The achievable average secrecy rate, due to the presence of a
line-of-sight component in the jammer channel is also evaluated.
Moreover, we study the detrimental effect of correlation across the
parallel sub-channels, and evaluate the corresponding decrease in the
achievable average secrecy rate for the various fading configurations.
We also investigate the tradeoff between the transmission power
and the jamming power for a fixed total power budget. Our
results, which are applicable to current orthogonal frequency division
multiplexing (OFDM) communications systems, shed further light on
the achievable average secrecy rates over a bank of parallel fading
channels in the presence of friendly jammers.
Abstract: There is a trend in development discourse to
understand and explain the level of corruption in Nigeria, its anticorruption
crusade and why it is failing, as well as its level of
compliance with International standards of United Nations
Convention against Corruption (UNCAC) & African Union
Convention on Converting and Preventing Corruption) to which
Nigeria is a signatory. This paper discusses the legal and
Constitutional provisions relating to corrupt practices and safeguards
in Nigeria, as well as the obstacles to the implementation of these
Conventions.
The paper highlights the challenges posed to the Anti-Corruption
crusade by analysing the loopholes that exist both in administrative
structure and in scope of the relevant laws. The paper argues that
Nigerian Constitution did not make adequate provisions for the
implementation of the conventions, hence a proposal which will
ensure adequate provision for implementing the conventions to better
the lives of Nigerians. The paper concludes that there is the need to
build institutional parameters, adequate constitutional and structural
safeguards, as well as to synergise strategies, collaborations and
alliances to facilitate the timely domestication and implementation of
the conventions.
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: In this paper, a new design of spherical robotic system
based on the concepts of gimbal structure and gyro dynamics is
presented. Robots equipped with multiple wheels and complex
steering mechanics may increase the weight and degrade the energy
transmission efficiency. In addition, the wheeled and legged robots are
relatively vulnerable to lateral impact and lack of lateral mobility.
Therefore, the proposed robotic design uses a spherical shell as the
main body for ground locomotion, instead of using wheel devices.
Three spherical shells are structured in a similar way to a gimbal
device and rotate like a gyro system. The design and mechanism of the
proposed robotic system is introduced. In addition, preliminary results
of the dynamic model based on the principles of planar rigid body
kinematics and Lagrangian equation are included. Simulation results
and rig construction are presented to verify the concepts.