Abstract: This paper presents small signal stability study carried
over the 140-Bus, 31-Machine, 5-Area MEPE system and validated
on free and open source software: PSAT. Well-established linearalgebra
analysis, eigenvalue analysis, is employed to determine the
small signal dynamic behavior of test system. The aspects of local
and interarea oscillations which may affect the operation and
behavior of power system are analyzed. Eigenvalue analysis is carried
out to investigate the small signal behavior of test system and the
participation factors have been determined to identify the
participation of the states in the variation of different mode shapes.
Also, the variations in oscillatory modes are presented to observe the
damping performance of the test system.
Abstract: Elastomeric dielectric material has recently become a
new alternative for actuator technology. The characteristics of
dielectric elastomers placed between two electrodes to withstand
large strain when electrodes are charged has attracted the attention of
many researcher to study this material for actuator technology. Thus,
in the past few years Danfoss Ventures A/S has established their own
dielectric electro-active polymer (DEAP), which was called
PolyPower.
The main objective of this work was to investigate the dynamic
characteristics for vibration control of a PolyPower actuator folded in
‘pull’ configuration. A range of experiments was carried out on the
folded actuator including passive (without electrical load) and active
(with electrical load) testing. For both categories static and dynamic
testing have been done to determine the behavior of folded DEAP
actuator.
Voltage-Strain experiments show that the DEAP folded actuator is
a non-linear system. It is also shown that the voltage supplied has no
effect on the natural frequency. Finally, varying AC voltage with
different amplitude and frequency shows the parameters that
influence the performance of DEAP folded actuator. As a result, the
actuator performance dominated by the frequency dependence of the
elastic response and was less influenced by dielectric properties.
Abstract: The 3D body movement signals captured during
human-human conversation include clues not only to the content of
people’s communication but also to their culture and personality.
This paper is concerned with automatic extraction of this information
from body movement signals. For the purpose of this research, we
collected a novel corpus from 27 subjects, arranged them into groups
according to their culture. We arranged each group into pairs and
each pair communicated with each other about different topics.
A state-of-art recognition system is applied to the problems of
person, culture, and topic recognition. We borrowed modeling,
classification, and normalization techniques from speech recognition.
We used Gaussian Mixture Modeling (GMM) as the main technique
for building our three systems, obtaining 77.78%, 55.47%, and
39.06% from the person, culture, and topic recognition systems
respectively. In addition, we combined the above GMM systems with
Support Vector Machines (SVM) to obtain 85.42%, 62.50%, and
40.63% accuracy for person, culture, and topic recognition
respectively.
Although direct comparison among these three recognition
systems is difficult, it seems that our person recognition system
performs best for both GMM and GMM-SVM, suggesting that intersubject
differences (i.e. subject’s personality traits) are a major
source of variation. When removing these traits from culture and
topic recognition systems using the Nuisance Attribute Projection
(NAP) and the Intersession Variability Compensation (ISVC)
techniques, we obtained 73.44% and 46.09% accuracy from culture
and topic recognition systems respectively.
Abstract: An experiment was conducted to determine the effect
of pollination on seed quality of rapeseed in Chitwan, Nepal during
2012-2013. The experiment was designed in Randomized Complete
Block with four replications and five treatments. The rapeseed plots
were caged with mosquito nets at 10% flowering except natural
pollination. Two-framed colonies of Apis mellifera L. and Apis
cerana F. were introduced separately for pollination, and control plot
caged without pollinators. The highest germination percent was
observed on Apis cerana F. pollinated plot seeds (90.50%
germination) followed by Apis mellifera L. pollinated plots (87.25 %)
and lowest on control plots (42.00% germination) seeds. Similarly,
seed test weight of Apis cerana F. pollinated plots (3.22 gm/ 1000
seed) and Apis mellifera L. pollinated plots (2.93 gm/1000 seed) were
and lowest on control plots (2.26 gm/ 1000 seed) recorded. Likewise,
oil content was recorded highest on pollinated by Apis cerana F.
(36.1%) followed by pollinated by Apis mellifera L. (35.4%) and
lowest on control plots (32.8%). This study clearly indicated
pollination increases the seed quality of rapeseed and therefore,
management of honeybee is necessary for producing higher quality of
rapeseed under Chitwan condition.
Abstract: The concentration levels of six heavy metals (Cd, Cr,
Fe, Ni, Pb and Zn) and two mineral elements (Ca and Mg) were
determined in soil samples collected from the vicinity of two auto
mechanic workshops in Sabon-Gari, Kaduna state, Nigeria, using
Atomic Absorption Spectrometry (AAS), in order to compare the
gradation of their concentrations with distance and depth of soil from
the workshop sites. At site 1, concentrations of Lead, Chromium, Iron
and Zinc were generally found to be above the World Health
Organization limits, while those of Nickel and Cadmium fell within
the limits. Iron had the highest concentration with a range of 176.274
ppm to 489.127 ppm at depths of 5 cm to 15 cm and a distance range
of 5 m to 15 m, while the concentration of cadmium was least with a
range of 0.001 ppm to 0.008 ppm at similar depth and distance
ranges. In addition, there was more of calcium (11.521 ppm to
121.709 ppm), in all the samples, than magnesium (11.293 ppm to
21.635 ppm). Similar results were obtained for site II. The
concentrations of all the metals analyzed showed a downward
gradient with increase in depth and distance from both workshop sites
except for iron and zinc at site 2. The immediate and remote
implications of these findings on the biota are discussed.
Abstract: The legends about “user-friendly” and “easy-to-use”
birotical tools (computer-related office tools) have been spreading
and misleading end-users. This approach has led us to the extremely
high number of incorrect documents, causing serious financial losses
in the creating, modifying, and retrieving processes. Our research
proved that there are at least two sources of this underachievement:
(1) The lack of the definition of the correctly edited, formatted
documents. Consequently, end-users do not know whether their
methods and results are correct or not. They are not aware of their
ignorance. They are so ignorant that their ignorance does not allow
them to realize their lack of knowledge. (2) The end-users’ problem
solving methods. We have found that in non-traditional programming
environments end-users apply, almost exclusively, surface approach
metacognitive methods to carry out their computer related activities,
which are proved less effective than deep approach methods.
Based on these findings we have developed deep approach
methods which are based on and adapted from traditional
programming languages. In this study, we focus on the most popular
type of birotical documents, the text based documents. We have
provided the definition of the correctly edited text, and based on this
definition, adapted the debugging method known in programming.
According to the method, before the realization of text editing, a
thorough debugging of already existing texts and the categorization
of errors are carried out. With this method in advance to real text
editing users learn the requirements of text based documents and also
of the correctly formatted text.
The method has been proved much more effective than the
previously applied surface approach methods. The advantages of the
method are that the real text handling requires much less human and
computer sources than clicking aimlessly in the GUI (Graphical User
Interface), and the data retrieval is much more effective than from
error-prone documents.
Abstract: Geometric and mechanical properties all influence the
resistance of RC structures and may, in certain combination of
property values, increase the risk of a brittle failure of the whole
system.
This paper presents a statistical and probabilistic investigation on
the resistance of RC beams designed according to Eurocodes 2 and 8,
and subjected to multiple failure modes, under both the natural
variation of material properties and the uncertainty associated with
cross-section and transverse reinforcement geometry. A full
probabilistic model based on JCSS Probabilistic Model Code is
derived. Different beams are studied through material nonlinear
analysis via Monte Carlo simulations. The resistance model is
consistent with Eurocode 2. Both a multivariate statistical evaluation
and the data clustering analysis of outcomes are then performed.
Results show that the ultimate load behaviour of RC beams
subjected to flexural and shear failure modes seems to be mainly
influenced by the combination of the mechanical properties of both
longitudinal reinforcement and stirrups, and the tensile strength of
concrete, of which the latter appears to affect the overall response of
the system in a nonlinear way. The model uncertainty of the
resistance model used in the analysis plays undoubtedly an important
role in interpreting results.
Abstract: The study examined the effect of Bonny Light whole
crude oil (WC) and its water soluble fraction (WSF) on the activities
of antioxidant enzymes (catalase (CAT) and superoxide dismutase
(SOD)) and crude mitochondria ATPases in the radicle of
germinating bean (Vigna unguiculata). The percentage germination,
level of lipid peroxidation, antioxidant enzyme and mitochondria
Ca2+ and Mg2+ ATPase activities were measured in the radicle of
bean after 7, 14 and 21 days post germination. Viable bean seeds
were planted in soils contaminated with 10ml, 25ml and 50ml of
whole crude oil (WC) and its water soluble fraction (WSF) to obtain
2, 5 and 10% v/w crude oil contamination. There was dose dependent
reduction of the number of bean seeds that germinated in the
contaminated soils compared with control (p
Abstract: Thin ZnO films are deposited on glass substrates via
sol–gel method and dip-coating. The films are prepared from zinc
acetate dehydrate as a starting reagent. After that the as-prepared
ZnO sol is aged for different periods (0, 1, 3, 5, 10, 15 and 30 days).
Nanocrystalline thin films are deposited from various sols. The
effect ZnO sols aging time on the structural and photocatalytic
properties of the films is studied. The films surface is studied by
Scanning Electron Microscopy. The effect of the aging time of the
starting solution is studied in the photocatalytic degradation of
Reactive Black 5 (RB5) by UV-vis spectroscopy. The experiments
are conducted upon UV-light illumination and in complete darkness.
The variation of the absorption spectra shows the degradation of RB5
dissolved in water, as a result of the reaction, occurring on the surface
of the films and promoted by UV irradiation. The initial
concentrations of dye (5, 10 and 20 ppm) and the effect of the aging
time are varied during the experiments. The results show, that the
increasing aging time of starting solution with respect to ZnO
generally promotes photocatalytic activity. The thin films obtained
from ZnO sol, which is aged 30 days have best photocatalytic
degradation of the dye (97,22%) in comparison with the freshly
prepared ones (65,92%). The samples and photocatalytic
experimental results are reproducible. Nevertheless, all films exhibit
a substantial activity in both UV light and darkness, which is
promising for the development of new ZnO photocatalysts by sol-gel
method.
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: These days, the field of tissue engineering is getting
serious attention due to its usefulness. Bone tissue engineering helps
to address and sort-out the critical sized and non-healing orthopedic
problems by the creation of manmade bone tissue. We will design
and validate an efficient numerical model, which will simulate the
effective diffusivity in bone tissue engineering. Our numerical model
will be based on the finite element analysis of the diffusion-reaction
equations. It will have the ability to optimize the diffusivity, even
at multi-scale, with the variation of time. It will also have a special
feature “parametric sweep”, with which we will be able to predict
the oxygen, glucose and cell density dynamics, more accurately. We
will fix these problems by modifying the governing equations, by
selecting appropriate spatio-temporal finite element schemes and by
transient analysis.
Abstract: Modelling of the earth's surface and evaluation of
urban environment, with 3D models, is an important research topic.
New stereo capabilities of high resolution optical satellites images,
such as the tri-stereo mode of Pleiades, combined with new image
matching algorithms, are now available and can be applied in urban
area analysis. In addition, photogrammetry software packages gained
new, more efficient matching algorithms, such as SGM, as well as
improved filters to deal with shadow areas, can achieve more dense
and more precise results.
This paper describes a comparison between 3D data extracted
from tri-stereo and dual stereo satellite images, combined with pixel
based matching and Wallis filter. The aim was to improve the
accuracy of 3D models especially in urban areas, in order to assess if
satellite images are appropriate for a rapid evaluation of urban
environments.
The results showed that 3D models achieved by Pleiades tri-stereo
outperformed, both in terms of accuracy and detail, the result
obtained from a Geo-eye pair. The assessment was made with
reference digital surface models derived from high resolution aerial
photography. This could mean that tri-stereo images can be
successfully used for the proposed urban change analyses.
Abstract: In this paper, the effect of grades 32.4 and 42.5
Portland-limestone cements generally used for concrete production in
Nigeria on concrete compressive strength is investigated.
Investigation revealed that the compressive strength of concrete
produced with Portland-limestone cement grade 42.5 is generally
higher than that produced with cement grade 32.5. The percentage
difference between the compressive strengths of the concrete cubes
produced with Portland-limestone cement grades 42.5 and 32.5 is
inversely proportional to the richness of the concrete with the highest
and the least percentage difference associated with the 1:2:4 and
1:1:2 mix ratios respectively. It is recommended that cement grade
42.5 be preferred for construction in Nigeria as this will lead to the
construction of stronger concrete structures, which will reduce the
incidence of failure of building and other concrete structures at no
additional cost since the cost of both cement grades are the same.
Abstract: Solar energy is a good option among renewable
energy resources due to its easy availability and abundance. The
simplest and most efficient way to utilize solar energy is to convert it
into thermal energy and this can be done with the help of solar
collectors. The thermal performance of such collectors is poor due to
less heat transfer from the collector surface to air. In this work,
experimental investigations of single pass solar air heater having
triangular duct and provided with roughness element on the underside
of the absorber plate. V-shaped ribs are used for investigation having
three different values of relative roughness pitch (p/e) ranges from 4-
16 for a fixed value of angle of attack (α), relative roughness height
(e/Dh) and a relative gap distance (d/x) values are 60°, 0.044 and 0.60
respectively. Result shows that considerable augmentation in heat
transfer has been obtained by providing roughness.
Abstract: This research focused on comparing the critical
thinking of the teacher students before and after using Miller’s Model
learning activities and investigating their opinions. The sampling
groups were (1) fourth year 33 student teachers majoring in Early
Childhood Education and enrolling in semester 1 of academic year
2013 (2) third year 28 student teachers majoring in English and
enrolling in semester 2 of academic year 2013 and (3) third year 22
student teachers majoring in Thai and enrolling in semester 2 of
academic year 2013. The research instruments were (1) lesson plans
where the learning activities were settled based on Miller’s Model (2)
critical thinking assessment criteria and (3) a questionnaire on
opinions towards Miller’s Model based learning activities. The
statistical treatment was mean, deviation, different scores and T-test.
The result unfolded that (1) the critical thinking of the students after
the assigned activities was better than before and (2) the students’
opinions towards the critical thinking improvement activities based
on Miller’s Model ranged from the level of high to highest.
Abstract: The use OF adhesive anchors for wooden constructions is an efficient technology to connect and design timber members in new timber structures and to rehabilitate the damaged structural members of historical buildings. Due to the lack of standard regulation in this specific area of structural design, designers’ choices are still supported by test analysis that enables knowledge, and the prediction, of the structural behaviour of glued in rod joints. The paper outlines an experimental research activity aimed at identifying the tensile resistance capacity of several new adhesive joint prototypes made of epoxy resin, steel bar and timber, Oak and Douglas Fir species. The development of new adhesive connectors has been carried out by using epoxy to glue stainless steel bars into pre-drilled holes, characterised by smooth and rough internal surfaces, in timber samples. The realization of a threaded contact surface using a specific drill bit has led to an improved bond between wood and epoxy. The applied changes have also reduced the cost of the joints’ production. The paper presents the results of this parametric analysis and a Finite Element analysis that enables identification and study of the internal stress distribution in the proposed adhesive anchors.
Abstract: This study was conducted in the area of Vlora Bay,
Albania. Data about Sea Turtles Caretta caretta and Chelonia mydas,
belonging to two periods of time (1984 – 1991; 2008 – 2014) are
given. All data gathered were analyzed using recent methodologies.
For all turtles captured (as by catch), the Curve Carapace Length
(CCL) and Curved Carapace Width (CCW) were measured. These
data were statistically analyzed, where the mean was 67.11 cm for
CCL and 57.57 cm for CCW of all individuals studied (n=13). All
untagged individuals of marine turtles were tagged using metallic
tags (Stockbrand’s titanium tag) with an Albanian address. Sex was
determined and resulted that 45.4% of individuals were females,
27.3% males and 27.3% juveniles. All turtles were studied for the
presence of the epibionts. The area of Vlora Bay is used from marine
turtles (Caretta caretta) as a migratory corridor to pass from
Mediterranean to the northern part of the Adriatic Sea.
Abstract: The well been of human beings on construction site is
very important, many man power had been lost through accidents
which kills or make workers physically unfit to carry out construction
activities, these in turn have multiple effects on the whole economy.
Thus it is necessary to put all safety items and regulations in place
before construction activities can commence. This study was carried
out in Ondo state of Nigeria to known and analyse the state of health
and safety of construction workers in the state. The study was done
using first hand observation method, 50 construction project sites
were visited in 10 major towns of Ondo state, questionnaires were
distributed and the results were analysed. The result show that
construction workers are being exposed to a lot of construction site
hazards due to lack of inadequate safety programmes and nonprovision
of appropriate safety materials for workers on site. From the
data gotten for each site visited and the statistical analysis, it can be
concluded that occurrence of accident on construction sites depends
significantly on the available safety facilities on the sites. The result of
the regression statistics show that the level of significant of the
dependence of occurrence of accident on the availability of safety
items on site is 0.0362 which is less than 0.05 maximum significant
level required. Therefore a vital way of sustaining our building
strategy is by given a detail attention to provision of adequate health
and safety items on construction sites which will reduce the
occurrence of accident, loss of man power and death of skilled
workers among others.
Abstract: Interaction between human, location and activity
defines space. In the framework of these relations, space is a
container for current specifications in relations of the 3 mentioned
elements. The change of land utility considered with average
performance range, urban regulations, society requirements etc. will
provide welfare and comfort for citizens. From an engineering view it
is fundamental that choosing a proper location for a specific civil
activity requires evaluation of locations from different perspectives.
The debate of desirable establishment of municipal service elements
in urban regions is one of the most important issues related to urban
planning. In this paper, the research type is applicable based on goal,
and is descriptive and analytical based on nature. Initially existing
terminals in Esfahan are surveyed and then new locations are
presented based on evaluated criteria. In order to evaluate terminals
based on the considered factors, an AHP model is used at first to
estimate weight of different factors and then existing and suggested
locations are evaluated using Arc GIS software and AHP model
results. The results show that existing bus terminals are located in
fairly proper locations. Further results of this study suggest new
locations to establish terminals based on urban criteria.
Abstract: Sandwich structure composites produced by epoxy
core and aluminium skin were developed as potential building
materials. Interface bonding between core and skin was controlled by
varying kenaf content. Five different weight percentage of kenaf
loading ranging from 10 wt% to 50 wt% were employed in the core
manufacturing in order to study the mechanical properties of the
sandwich composite. Properties of skin aluminium with epoxy were
found to be affected by drying time of the adhesive. Mechanical
behavior of manufactured sandwich composites in relation with
properties of constituent materials was studied. It was found that 30
wt% of kenaf loading contributed to increase the flexural strength and
flexural modulus up to 102 MPa and 32 GPa, respectively. Analysis
were done on the flatwise and edgewise compression test. For
flatwise test, it was found that 30 wt% of fiber loading could
withstand maximum force until 250 kN, with compressive strength
results at 96.94 MPa. However, at edgewise compression test, the
sandwich composite with same fiber loading only can withstand 31
kN of the maximum load with 62 MPa of compressive strength
results.