Abstract: Composite material based on Fe3Si micro-particles
and Mn-Zn nano-ferrite was prepared using powder metallurgy
technology. The sol-gel followed by autocombustion process was
used for synthesis of Mn0.8Zn0.2Fe2O4 ferrite. 3 wt.% of mechanically
milled ferrite was mixed with Fe3Si powder alloy. Mixed micro-nano
powder system was homogenized by the Resonant Acoustic Mixing
using ResodynLabRAM Mixer. This non-invasive homogenization
technique was used to preserve spherical morphology of Fe3Si
powder particles. Uniaxial cold pressing in the closed die at pressure
600 MPa was applied to obtain a compact sample. Microwave
sintering of green compact was realized at 800°C, 20 minutes, in air.
Density of the powders and composite was measured by
Hepycnometry. Impulse excitation method was used to measure
elastic properties of sintered composite. Mechanical properties were
evaluated by measurement of transverse rupture strength (TRS) and
Vickers hardness (HV). Resistivity was measured by 4 point probe
method. Ferrite phase distribution in volume of the composite was
documented by metallographic analysis.
It has been found that nano-ferrite particle distributed among
micro- particles of Fe3Si powder alloy led to high relative density
(~93%) and suitable mechanical properties (TRS >100 MPa, HV
~1GPa, E-modulus ~140 GPa) of the composite. High electric
resistivity (R~6.7 ohm.cm) of prepared composite indicate their
potential application as soft magnetic material at medium and high
frequencies.
Abstract: Urban areas have been expanded throughout the
globe. Monitoring and modelling urban growth have become a
necessity for a sustainable urban planning and decision making.
Urban prediction models are important tools for analyzing the causes
and consequences of urban land use dynamics. The objective of this
research paper is to analyze and model the urban change, which has
been occurred from 1990 to 2000 using CORINE land cover maps.
The model was developed using drivers of urban changes (such as
road distance, slope, etc.) under an Artificial Neural Network
modelling approach. Validation was achieved using a prediction map
for 2006 which was compared with a real map of Urban Atlas of
2006. The accuracy produced a Kappa index of agreement of 0,639
and a value of Cramer's V of 0,648. These encouraging results
indicate the importance of the developed urban growth prediction
model which using a set of available common biophysical drivers
could serve as a management tool for the assessment of urban
change.
Abstract: In this study was monitored the population of the
European Pond Turtle, Emys orbicularis (Linnaeus, 1758) in the area
of Narta Lagoon, Vlora Bay (Albania), from August to October 2014.
A total of 54 individuals of E. orbicularis were studied using
different methodologies. Curved Carapace Length (CCL), Plastron
Length (PL) and Curved Carapace Width (CCW) were measured for
each individual of E. orbicularis and were statistically analyzed. All
captured turtles were separated in seven different size – classes based
on their carapace length (CCL). Each individual of E. orbicularis was
marked by notching the carapace (marginal scutes). Form all
individuals captured resulted that 37 were females (68.5%), 14 males
(25.9%), 3 juveniles (5.5%), while 18 individuals of E. orbicularis
were recaptured for the first and some for the second time.
Abstract: Teachers can play a huge role in encouraging students
to use computers and can affect students’ attitudes towards
computers. So understanding teachers’ beliefs and their use of
computers is an important way to create effective motivational
systems for teachers to use computers in the classroom in an effective
way. A qualitative study (6 focus group) was carried out among
Saudi High school teachers, both male and female, to examine their
attitudes towards computers and to find out their computer skills and
usage. The study showed a gender differences in that females were
less likely to attend computer workshops, females also had less
computer skills, and they have more negative attitudes towards
computers than males. Also the study found that low computer skills
in the classroom made students unlikely to have the lessons presented
using computers. Furthermore, the study found some factors that
effected teachers’ attitudes towards computers. These factors were
computer experience and confidence as much having skills and good
experience in computer use, the role and importance of computers
had become in their life and in teaching as well.
Abstract: In this paper we describe one critical research
program within a complex, ongoing multi-year project (2010 to 2014
inclusive) with the overall goal to improve the learning outcomes for
first year undergraduate commerce/business students within an
Information Systems (IS) subject with very large enrolment. The
single research program described in this paper is the analysis of
student attitudes and decision making in relation to the availability of
formative assessment feedback via Web-based real time conferencing
and document exchange software (Adobe Connect). The formative
assessment feedback between teaching staff and students is in respect
of an authentic problem-based, team-completed assignment. The
analysis of student attitudes and decision making is investigated via
both qualitative (firstly) and quantitative (secondly) application of the
Theory of Planned Behavior (TPB) with a two statistically-significant
and separate trial samples of the enrolled students. The initial
qualitative TPB investigation revealed that perceived self-efficacy,
improved time-management, and lecturer-student relationship
building were the major factors in shaping an overall favorable
student attitude to online feedback, whilst some students expressed
valid concerns with perceived control limitations identified within the
online feedback protocols. The subsequent quantitative TPB
investigation then confirmed that attitude towards usage, subjective
norms surrounding usage, and perceived behavioral control of usage
were all significant in shaping student intention to use the online
feedback protocol, with these three variables explaining 63 percent of
the variance in the behavioral intention to use the online feedback
protocol. The identification in this research of perceived behavioral
control as a significant determinant in student usage of a specific
technology component within a virtual learning environment (VLE)
suggests that VLEs could now be viewed not as a single, atomic
entity, but as a spectrum of technology offerings ranging from the
mature and simple (e.g., email, Web downloads) to the cutting-edge
and challenging (e.g., Web conferencing and real-time document
exchange). That is, that all VLEs should not be considered the same.
The results of this research suggest that tertiary students have the
technological sophistication to assess a VLE in this more selective
manner.
Abstract: This work presents synthesis of α,ω-dithienyl
terminated poly(ethylene glycol) (PEGTh) capable for further chain
extension by either chemical or electrochemical polymeriztion.
PEGTh was characterized by FTIR and 1H-NMR. Further
copolymerization of PEGTh and pyrrole (Py) was performed by
chemical oxidative polymerization using ceric (IV) salt as an oxidant
(PPy-PEGTh). PEG without end group modification was used
directly to prepare copolymers with Py by Ce (IV) salt (PPy-PEG).
Block copolymers with mole ratio of pyrrole to PEGTh (PEG) 50:1
and 10:1 were synthesized. The electrical conductivities of
copolymers PPy-PEGTh and PPy-PEG were determined by four
point probe technique. Influence of the synthetic route and content of
the insulating segment on conductivity and yield of the copolymers
were investigated.
Abstract: A Motzkin shift is a mathematical model for constraints
on genetic sequences. In terms of the theory of symbolic dynamics,
the Motzkin shift is nonsofic, and therefore, we cannot use the Perron-
Frobenius theory to calculate its topological entropy. The Motzkin
shift M(M,N) which comes from language theory, is defined to be the
shift system over an alphabet A that consists of N negative symbols,
N positive symbols and M neutral symbols. For an x in the full shift,
x will be in the Motzkin subshift M(M,N) if and only if every finite
block appearing in x has a non-zero reduced form. Therefore, the
constraint for x cannot be bounded in length. K. Inoue has shown that
the entropy of the Motzkin shift M(M,N) is log(M + N + 1). In this
paper, a new direct method of calculating the topological entropy of
the Motzkin shift is given without any measure theoretical discussion.
Abstract: This paper introduces novel approaches to partitioning
and mapping in terms of model-based embedded multicore system
engineering and further discusses benefits, industrial relevance and
features in common with existing approaches. In order to assess
and evaluate results, both approaches have been applied to a real
industrial application as well as to various prototypical demonstrative
applications, that have been developed and implemented for
different purposes. Evaluations show, that such applications improve
significantly according to performance, energy efficiency, meeting
timing constraints and covering maintaining issues by using
the AMALTHEA platform and the implemented approaches.
Furthermore, the model-based design provides an open, expandable,
platform independent and scalable exchange format between
OEMs, suppliers and developers on different levels. Our proposed
mechanisms provide meaningful multicore system utilization since
load balancing by means of partitioning and mapping is effectively
performed with regard to the modeled systems including hardware,
software, operating system, scheduling, constraints, configuration and
more data.
Abstract: Physics Education Research (PER) results have shown
that students do not achieve the expected level of competency in
understanding the concepts of different domains of Physics learning
when taught by the traditional teaching methods, the concepts of
Electricity and Magnetism (E&M) being one among them.
Simulation being one of the valuable instructional tools renders an
opportunity to visualize varied experiences with such concepts.
Considering the electric force concept which requires extensive use
of vector representations, we report here the outcome of the research
results pertaining to the student understanding of this concept and the
role of simulation in using vector representation. The simulation
platform provides a positive impact on the use of vector
representation.
The first stage of this study involves eliciting and analyzing
student responses to questions that probe their understanding of the
concept of electrostatic force and this is followed by four stages of
student interviews as they use the interactive simulations of electric
force in one dimension. Student responses to the questions are
recorded in real time using electronic pad. A validation test interview
is conducted to evaluate students' understanding of the electric force
concept after using interactive simulation. Results indicate lack of
procedural knowledge of the vector representation. The study
emphasizes the need for the choice of appropriate simulation and
mode of induction for learning.
Abstract: Mahasweta Devi and Toni Morrison are the two
stalwarts of the Indian English and the Afro-American literature
respectively. The writings of these two novelists are authentic and
powerful records of the lives of the people because much of their
personal experiences have gone into the making of their works. Devi,
a representative force of the Indian English literature, is also a social
activist working with the tribals of Bihar, Jharkhand, Orissa and West
Bengal. Most of her works echo the lives and struggles of the
subalterns as is evident in her “best beloved book” Chotti Munda and
His Arrow. The novelist focuses on the struggle of the tribals against
the colonial and the feudal powers to create their own identity,
thereby, embarking on the ideological project of ‘setting the record
straight’. The Nobel Laureate Toni Morrison, on the other hand,
brings to the fore the crucial issues of gender, race and class in many
of her significant works. In one of her representative works Sula, the
protagonist emerges as a non- conformist and directly confronts the
notion of a ‘good woman’ nurtured by the community of the Blacks.
In addition to this, the struggle of the Blacks against the White
domination, also become an important theme of the text. The thrust
of the paper lies in making a critical analysis of the portrayal of the
heroic attempts of the subaltern protagonist and the artistic endeavor
of the novelists in challenging the stereotypes.
Abstract: This study presents synthesis of novel block
copolymers of thienyl end capped ethoxylated nonyl phenol and
pyrrole via chemical oxidative polymerization. Ethoxylated nonyl
phenol (ENP) was reacted with 2-thiophenecarbonyl chloride in order
to synthesize a macromonomer containing thienyl end-group (ENPThC).
Then copolymers of ENP-ThC and pyrrole were synthesized
by chemical oxidative polymerization using iron (III) chloride as an
oxidant. ENP-ThC served both as a macromonomer and an emulsifier
for pyrrole with poor solubility in water.
The synthesized block copolymers (ENP-ThC-b-PPy) were
characterized by spectroscopic analysis and the electrical
conductivities were investigated with 4-point probe technique.
Abstract: The article deals with one of the most significant
issues concerning the functioning of the public sector in the European
Union. The objectives of good governance were formulated by the
EU itself and also the Scholars in reaction to the discussion that
started a decade ago and concerned the role of the government in 21st
century, the future of integration processes and globalization
challenges in Europe. Currently, the concept of good governance is
mainly associated with the improvement of management of public
policies in the European Union, concerning both domestic and EU
policies. However, it goes beyond the issues of state capacity and
effectiveness of management. Good governance relates also to
societal participation in the public administration and verification of
decisions made in public authorities’ (including public
administration). Indirectly, the concept and practice of good
governance are connected to societal legitimisation of public bodies
in the European Union.
Abstract: Periventricular Leukomalacia (PVL) is a White Matter
Injury (WMI) of preterm neonatal brain. Objectives of the study were
to assess the neuro-developmental outcome at one year of age and to
determine a good protocol of cranial ultrasonography to detect PVL.
Two hundred and sixty four preterm neonates were included in the
study. Series of cranial ultrasound scans were done by using a
dedicated neonatal head probe 4-10 MHz of Logic e portable
ultrasound scanner. Clinical history of seizures, abnormal head
growth (hydrocephalus or microcephaly) and developmental
milestones were assessed and neurological examinations were done
until one year of age. Among live neonates, 57% who had cystic PVL
(Grades 2 and 3) manifested as cerebral palsy. In conclusion cystic
PVL has permanent neurological disabilities like cerebral palsy.
Good protocol of real time cranial ultrasonography to detect PVL is
to perform scans at least once a week until one month and at term (40
weeks of gestation).
Abstract: In this paper, the dynamic characteristics of a threelobe
journal bearing lubricated with micropolar fluids are determined
by the linear stability theory. Lubricating oil containing additives and
contaminants is modelled as micropolar fluid. The modified
Reynolds equation is obtained using the micropolar lubrication theory
.The finite difference technique has been used to determine the
solution of the modified Reynolds equation. The dynamic
characteristics in terms of stiffness, damping coefficients, the critical
mass and whirl ratio are determined for various values of size of
material characteristic length and the coupling number. The
computed results show that the three-lobe bearing lubricated with
micropolar fluid exhibits better stability compared with that
lubricated with Newtonian fluid. According to the results obtained,
the effect of the parameter micropolar fluid is remarkable on the
dynamic characteristics and stability of the three-lobe bearing.
Abstract: The study is devoted to define the optimal conditions
for the nitriding of pure iron at atmospheric pressure by using NH3-
Ar-C3H8 gas mixtures. After studying the mechanisms of phase
formation and mass transfer at the gas-solid interface, a mathematical
model is developed in order to predict the nitrogen transfer rate in the
solid, the ε-carbonitride layer growth rate and the nitrogen and
carbon concentration profiles. In order to validate the model and to
show its possibilities, it is compared with thermogravimetric
experiments, analyses and metallurgical observations (X-ray
diffraction, optical microscopy and electron microprobe analysis).
Results obtained allow us to demonstrate the sound correlation
between the experimental results and the theoretical predictions.
Abstract: Magnetic powder of Sr-ferrite was prepared by
conventional and sol-gel auto-combustion methods. In conventional
method, strontium carbonate and ferric oxide powders were mixed
together and then mixture was calcined. In sol-gel auto-combustion
method, a solution containing strontium nitrate, ferric nitrate and
citric acid was heated until the combustion took place automatically;
then, as-burnt powder was calcined. Thermal behavior, phase
identification, morphology and magnetic properties of powders
obtained by these two methods were compared by DTA, XRD, SEM
and VSM techniques. According to the results of DTA analysis,
formation temperature of Sr-ferrite obtained by conventional and solgel
auto-combustion methods were 1300°C and 1000°C, respectively.
XRD results confirmed the formation of pure Sr-ferrite at the
mentioned temperatures. Plate and hexagonal-shape particles of Srferrite
were observed using SEM. The Sr-ferrite powder obtained by
sol-gel auto-combustion method had saturation magnetization of
66.03 emu/g and coercivity of 5731 Oe in comparison with values of
58.20 emu/g and 4378 Oe obtained by conventional method.
Abstract: Climate warming would increase rainfall by shifting
precipitation falling form from snow to rain, and would accelerate
snow cover disappearing by increasing snowpack. Using temperature
and precipitation data in the temperature-index snowmelt model, we
evaluated variability of snowfall and continuous snow cover duration
(CSCD) during 1944-2010 over Pelso, central Finland. Mann-
Kendall non-parametric test determined that annual precipitation
increased by 2.69 (mm/year, p
Abstract: The development of the agricultural sector in Ghana
has been reliant on the use of irrigation systems to ensure food
security. However, the manual operation of these systems has not
facilitated their maximum efficiency due to human limitations.
This paper seeks to address this problem by designing and
implementing an efficient, cost effective automated system which
monitors and controls the water flow of irrigation through
communication with an authorized operator via text messages. The
automatic control component of the system is timer based with an
Atmega32 microcontroller and a real time clock from the SM5100B
cellular module. For monitoring purposes, the system sends periodic
notification of the system on the performance of duty via SMS to the
authorized person(s). Moreover, the GSM based Irrigation
Monitoring and Control System saves time and labour and reduces
cost of operating irrigation systems by saving electricity usage and
conserving water.
Field tests conducted have proven its operational efficiency and
ease of assessment of farm irrigation equipment due to its costeffectiveness
and data logging capabilities.
Abstract: In our paper we describe the security capabilities of
data collection. Data are collected with probes located in the near and
distant surroundings of the company. Considering the numerous
obstacles e.g. forests, hills, urban areas, the data collection is realized
in several ways. The collection of data uses connection via wireless
communication, LAN network, GSM network and in certain areas
data are collected by using vehicles. In order to ensure the connection
to the server most of the probes have ability to communicate in
several ways. Collected data are archived and subsequently used in
supervisory applications.
To ensure the collection of the required data, it is necessary to
propose algorithms that will allow the probes to select suitable
communication channel.
Abstract: The phased-array ultrasound transducer types are
utilities for medical ultrasonography as well as optical imaging.
However, their discontinuity characteristic limits the applications due
to the artifacts contaminated into the reconstructed images. Because
of the effects of the ultrasound pressure field pattern to the echo
ultrasonic waves as well as the optical modulated signal, the side
lobes of the focused ultrasound beam induced by discontinuity of the
phased-array ultrasound transducer might the reason of the artifacts.
In this paper, a simple method in approach of numerical simulation
was used to investigate the limitation of discontinuity of the elements
in phased-array ultrasound transducer and their effects to the
ultrasound pressure field. Take into account the change of ultrasound
pressure field patterns in the conditions of variation of the pitches
between elements of the phased-array ultrasound transducer, the
appropriated parameters for phased-array ultrasound transducer
design were asserted quantitatively.