Abstract: Groundwater inflow to the tunnels is one of the most
important problems in tunneling operation. The objective of this
study is the investigation of model dimension effects on tunnel inflow
assessment in discontinuous rock masses using numerical modeling.
In the numerical simulation, the model dimension has an important
role in prediction of water inflow rate. When the model dimension is
very small, due to low distance to the tunnel border, the model
boundary conditions affect the estimated amount of groundwater flow
into the tunnel and results show a very high inflow to tunnel. Hence,
in this study, the two-dimensional universal distinct element code
(UDEC) used and the impact of different model parameters, such as
tunnel radius, joint spacing, horizontal and vertical model domain
extent has been evaluated. Results show that the model domain extent
is a function of the most significant parameters, which are tunnel
radius and joint spacing.
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: This paper attempts to define the validity domain of
LSDP (Loop Shaping Design Procedure) controller system, by
determining the suitable uncertainty region, so that linear system be
stable. Indeed the LSDP controller cannot provide stability for any
perturbed system. For this, we will use the gap metric tool that is
introduced into the control literature for studying robustness
properties of feedback systems with uncertainty. A 2nd order electric
linear system example is given to define the validity domain of LSDP
controller and effectiveness gap metric.
Abstract: This paper examines the effect of the volatility of oil
prices on food price in South Africa using monthly data covering the
period 2002:01 to 2014:09. Food price is measured by the South
African consumer price index for food while oil price is proxied by
the Brent crude oil. The study employs the GARCH-in-mean VAR
model, which allows the investigation of the effect of a negative and
positive shock in oil price volatility on food price. The model also
allows the oil price uncertainty to be measured as the conditional
standard deviation of a one-step-ahead forecast error of the change in
oil price. The results show that oil price uncertainty has a positive
and significant effect on food price in South Africa. The responses of
food price to a positive and negative oil price shocks is asymmetric.
Abstract: Recently, the competition between websites becomes
intense. How to make users “adopt” their websites is an issue of urgent
importance for online communities companies. Social procedures
(such as social influence) can possibly explain how and why users’
technologies usage behaviors affect other people to use the
technologies. This study proposes two types of social influences on the
initial usage of Facebook Check In-friends and group members.
Besides, this study combines social influences theory and social
network theory to explore the factors influencing initial usage of
Facebook Check In. This study indicates that Facebook friends’
previous usage of Facebook Check In and Facebook group members’
previous usage of Facebook Check In will positively influence focal
actors’ Facebook Check In adoption intention, and network centrality
will moderate the relationships among Facebook friends’ previous
usage of Facebook Check In, Facebook group members’ previous
usage of Facebook Check In and focal actors’ Facebook Check In
adoption intention. The article concludes with contributions to
academic research and practice.
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: The feedbacks obtained regarding the sense of
presence from pilot users operating a Mobile Robotic presence
(MRP) system to visit a simulated museum are reported in this paper.
The aim is to investigate how much the perception of system’s
usefulness and ease of use is affected by operators’ sense of social
telepresence (presence) in the remote location. Therefore, scenarios
of visiting a museum are simulated and the user operators are
supposed to perform some regular tasks inside the remote
environment including interaction with local users, navigation and
visiting the artworks. Participants were divided into two groups,
those who had previous experience of operation and interaction with
a MRP system and those who never had experience. Based on the
results, both groups provided different feedbacks. Moreover, there
was a significant association between user’s sense of presence and
their perception of system usefulness and ease of use.
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: 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: Soil quality monitoring is a science-based soil
management tool that assesses soil ecosystem health.
A soil monitoring program in Auckland, New Zealand’s largest
city extends from 1995 to the present. The objective of this study was
to firstly determine changes in soil parameters (basic soil properties
and heavy metals) that were assessed from rural land in 1995-2000
and repeated in 2008-2012. The second objective was to determine
differences in soil parameters across various land uses including
native bush, rural (horticulture, pasture and plantation forestry) and
urban land uses using soil data collected in more recent years (2009-
2013).
Across rural land, mean concentrations of Olsen P had
significantly increased in the second sampling period and was
identified as the indicator of most concern, followed by soil
macroporosity, particularly for horticultural and pastoral land. Mean
concentrations of Cd were also greatest for pastoral and horticultural
land and a positive correlation existed between these two parameters,
which highlights the importance of analysing basic soil parameters in
conjunction with heavy metals. In contrast, mean concentrations of
As, Cr, Pb, Ni and Zn were greatest for urban sites. Native bush sites
had the lowest concentrations of heavy metals and were used to
calculate a ‘pollution index’ (PI). The mean PI was classified as high
(PI > 3) for Cd and Ni and moderate for Pb, Zn, Cr, Cu, As and Hg,
indicating high levels of heavy metal pollution across both rural and
urban soils. From a land use perspective, the mean ‘integrated
pollution index’ was highest for urban sites at 2.9 followed by
pasture, horticulture and plantation forests at 2.7, 2.6 and 0.9,
respectively.
It is recommended that soil sampling continues over time because
a longer spanning record will allow further identification of where
soil problems exist and where resources need to be targeted in the
future. Findings from this study will also inform policy and science
direction in regional councils.
Abstract: Silica was extracted from agriculture waste rice husk
ash (RHA) and was used as the silica source for synthesis of
RMCM-48 and RSBA-16. An alkali fusion process was utilized to
separate silicate supernatant and the sediment effectively. The
CTAB/Si and F127/Si molar ratio was employed to control the
structure properties of the obtained RMCM-48 and RSBA-16
materials. The N2 adsorption-desorption results showed the
micro-mesoporous RSBA-16 possessed high specific surface areas
(662-1001 m2/g). All the obtained RSBA-16 materials were applied as
the adsorbents for acetone adsorption. And the breakthrough tests
clearly revealed that the RSBA-16(0.004) materials could achieve the
highest acetone adsorption capacity of 181 mg/g under 1000 ppmv
acetone vapor concentration at 25oC, which was also superior to
ZSM-5 (71mg/g) and MCM-41 (157mg/g) under same test conditions.
This can help to reduce the solid waste and the high adsorption
performance of the obtained materials could consider as potential
adsorbents for acetone adsorption.
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: 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: The development of active and stable catalysts
without noble metals for low temperature oxidation of exhaust gases
remains a significant challenge. The purpose of this study is to
determine the influence of the preparation method on the catalytic
activity of the supported copper-manganese mixed oxides in terms of
VOCs oxidation. The catalysts were prepared by impregnation of γ-
Al2O3 with copper and manganese nitrates and acetates and the
possibilities for CO, CH3OH and dimethyl ether (DME) oxidation
were evaluated using continuous flow equipment with a four-channel
isothermal stainless steel reactor. Effect of the support, Cu/Mn mole
ratio, heat treatment of the precursor and active component loading
were investigated. Highly active alumina supported Cu-Mn catalysts
for CO and VOCs oxidation were synthesized. The effect of
preparation conditions on the activity behavior of the catalysts was
discussed.
The synergetic interaction between copper and manganese species
increases the activity for complete oxidation over mixed catalysts.
Type of support, calcination temperature and active component
loading along with catalyst composition are important factors,
determining catalytic activity. Cu/Mn molar ratio of 1:5, heat
treatment at 450oC and 20 % active component loading are the best
compromise for production of active catalyst for simultaneous
combustion of CO, CH3OH and DME.
Abstract: Recently, the green architecture becomes a
significant way to a sustainable future. Green building designs
involve finding the balance between comfortable homebuilding and
sustainable environment. Moreover, the utilization of the new
technologies such as artificial intelligence techniques are used to
complement current practices in creating greener structures to keep
the built environment more sustainable. The most common objectives
in green buildings should be designed to minimize the overall impact
of the built environment that effect on ecosystems in general and in
particularly human health and natural environment. This will lead to
protecting occupant health, improving employee productivity,
reducing pollution and sustaining the environmental. In green
building design, multiple parameters which may be interrelated,
contradicting, vague and of qualitative/quantitative nature are
broaden to use. This paper presents a comprehensive critical state- ofart-
review of current practices based on fuzzy and its combination
techniques. Also, presented how green architecture/building can be
improved using the technologies that been used for analysis to seek
optimal green solutions strategies and models to assist in making the
best possible decision out of different alternatives.
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: Data mining idea is mounting rapidly in admiration
and also in their popularity. The foremost aspire of data mining
method is to extract data from a huge data set into several forms that
could be comprehended for additional use. The data mining is a
technology that contains with rich potential resources which could be
supportive for industries and businesses that pay attention to collect
the necessary information of the data to discover their customer’s
performances. For extracting data there are several methods are
available such as Classification, Clustering, Association,
Discovering, and Visualization… etc., which has its individual and
diverse algorithms towards the effort to fit an appropriate model to
the data. STATISTICA mostly deals with excessive groups of data
that imposes vast rigorous computational constraints. These results
trials challenge cause the emergence of powerful STATISTICA Data
Mining technologies. In this survey an overview of the STATISTICA
software is illustrated along with their significant features.
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.