Abstract: To achieve reliable welds with minimum distortion for
the fabrication of components in aerospace industry laser beam
welding is attempted. Laser welding can provide a significant benefit
for the welding of Titanium and Aluminium thin sheet alloys of its
precision and rapid processing capability. For laser welding, pulse
shape, energy, duration, repetition rate and peak power are the most
important parameters that influence directly the quality of welds. In
this experimental work for joining 1mm thick TI6AL4V and AA2024
alloy and JK600 Nd:YAG pulsed laser units used. The distortions at
different welding power and speed of titanium and aluminium thin
sheet alloys are investigated. Test results reveal that increase in
welding speed increases distortion in weldment
Abstract: The practice of freeing monuments from subsequent
additions crosses the entire history of conservation and it is
traditionally connected to the aim of valorisation, both for cultural
and educational purpose and recently even for touristic exploitation.
Defence heritage has been widely interested by these cultural and
technical moods from philological restoration to critic innovations. A
renovated critical analysis of Italian episodes and in particular the
Sardinian case of the area of San Pancrazio in Cagliari, constitute an
important lesson about the limits of this practice and the uncertainty
in terms of results, towards the definition of a sustainable good
practice in the restoration of military architectures.
Abstract: Graphical User Interface (GUI) is essential to
programming, as is any other characteristic or feature, due to the fact
that GUI components provide the fundamental interaction between
the user and the program. Thus, we must give more interest to GUI
during building and development of systems. Also, we must give a
greater attention to the user who is the basic corner in the dealing
with the GUI. This paper introduces an approach for designing GUI
from one of the models of business workflows which describe the
workflow behavior of a system, specifically through Activity
Diagrams (AD).
Abstract: Generally the natural environment is made up of air,
water and soil. The release of emission of industrial waste into
anyone of the components of the environment causes pollution.
Industrial pollution significantly threatens the inherent right of
people, to the enjoyment of a safe and secure environment. The aim
of this paper is to assess the effect of environmental pollution and
health risks of residents living near Ewekoro cement factory. The
research made use of IKONOS imagery for Geographical
Information System (GIS) to buffer and extract buildings that are less
than 1km to the factory, within 1km to 5km and above 5km to the
factory. Also questionnaire was used to elicit information on the
socio-economic factors, effect of environmental pollution on
residents and measures adopted to control industrial pollution on the
residents. Findings show that most buildings that fall between less
than 1km and 1km to 5km to the factory have high health risk in the
study area. The study recommended total relocation for the residents
of the study area to reduce health risk problems.
Abstract: An investigation into Cahn-Hilliard equation was
carried out through numerical simulation to identify a possible phase
separation for one and two dimensional domains. It was observed that
this equation can reproduce important mass fluxes necessary for
phase separation within the miscibility gap and for coalescence of
particles.
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: Random epistemologies and hash tables have garnered
minimal interest from both security experts and experts in the last
several years. In fact, few information theorists would disagree with
the evaluation of expert systems. In our research, we discover how
flip-flop gates can be applied to the study of superpages. Though
such a hypothesis at first glance seems perverse, it is derived from
known results.
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: Speech Segmentation is the measure of the change
point detection for partitioning an input speech signal into regions
each of which accords to only one speaker. In this paper, we apply
two features based on multi-scale product (MP) of the clean speech,
namely the spectral centroid of MP, and the zero crossings rate of
MP. We focus on multi-scale product analysis as an important tool
for segmentation extraction. The MP is based on making the product
of the speech wavelet transform coefficients (WTC). We have
estimated our method on the Keele database. The results show the
effectiveness of our method. It indicates that the two features can find
word boundaries, and extracted the segments of the clean speech.
Abstract: Arising problems of countries’ public finances, social
and demographic changes motivate scientific and policy debates on
public spending size, structure and efficiency in order to meet the
changing needs of society and business. The concept of sustainable
development poses new challenges for scientists and policy-makers
in the field of public finance. This paper focuses on the investigation
of the relationship between government expenditure and country’s
economic development in the context of sustainable development.
Empirical analysis focuses on the data of the European Union (except
Croatia and Luxemburg) countries. The study covers 2003 – 2012
years, using annual cross-sectional data. Summarizing the research
results, it can be stated that governments should pay more attention to
the needs that ensure sustainable development in the long-run when
formulating public expenditure policy, particularly in the field of
environment protection.
Abstract: Recently, universities are increasingly consuming
energy to support various activities. A large population of staff and
students in Malaysian universities has led to excessive energy
consumption which directly gives an impact to the environment. The
key question then ascended “How well is an energy management
(EM) been practiced in universities without taking the Critical
Success Factors (CSFs) into consideration to ensure the management
of university achieves the goals in reducing energy consumption.
Review on past literature is carried out to establish CSFs for EM best
practices. Thus, this paper highlighted the CSFs which have to be
focused on by management of university to successfully measure the
EM implementation and its performance. At the end of this paper, a
theoretical framework is developed for EM success factors towards
sustainable university.
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: Neurons in the nervous system communicate with
each other by producing electrical signals called spikes. To
investigate the physiological function of nervous system it is essential
to study the activity of neurons by detecting and sorting spikes in the
recorded signal. In this paper a method is proposed for considering
the spike sorting problem which is based on the nonlinear modeling
of spikes using exponential autoregressive model. The genetic
algorithm is utilized for model parameter estimation. In this regard
some selected model coefficients are used as features for sorting
purposes. For optimal selection of model coefficients, self-organizing
feature map is used. The results show that modeling of spikes with
nonlinear autoregressive model outperforms its linear counterpart.
Also the extracted features based on the coefficients of exponential
autoregressive model are better than wavelet based extracted features
and get more compact and well-separated clusters. In the case of
spikes different in small-scale structures where principal component
analysis fails to get separated clouds in the feature space, the
proposed method can obtain well-separated cluster which removes
the necessity of applying complex classifiers.
Abstract: The aim of this study is to evaluate the effects of the
laser and partial vibration stimulation on the mice tibia with
morphological characteristics. Twenty female C57BL/6 mice (12
weeks old) were used for the experiment. The study was carried out on
four groups of animals each consisting of five mice. Four groups of
mice were ovariectomized. Animals were scanned at 0 and 2 weeks
after ovariectomy by using micro computed tomography to estimate
morphological characteristics of tibial trabecular bone. Morphological
analysis showed that structural parameters of multi-stimuli group
appear significantly better phase in BV/TV, BS/BV, Tb.Th, Tb.N,
Tb.Sp, and Tb.pf than single stimulation groups. However, single
stimulation groups didn’t show significant effect on tibia with Sham
group. This study suggests that multi-stimuli may restrain the change
as the degenerate phase on osteoporosis in the mice tibia.
Abstract: Diffusion stills have been effective in water
desalination. The present work represents a model of the distillation
process by using vertical single-effect diffusion stills. A semianalytical
model has been developed to model the process. A
software computer code using Engineering Equation Solver EES
software has been developed to solve the equations of the developed
model. An experimental setup has been constructed, and used for the
validation of the model. The model is also validated against former
literature results. The results obtained from the present experimental
test rig, and the data from the literature, have been compared with the
results of the code to find its best range of validity. In addition, a
parametric analysis of the system has been developed using the
model to determine the effect of operating conditions on the system's
performance. The dominant parameters that affect the productivity of
the still are the hot plate temperature that ranges from (55- 90°C) and
feed flow rate in range of (0.00694-0.0211 kg/m2-s).
Abstract: PLA emerged as a promising polymer because of its
property as a compostable, biodegradable thermoplastic made from
renewable sources. PLA can be polymerized from monomers
(Lactide or Lactic acid) obtained by fermentation processes from
renewable sources such as corn starch or sugarcane. For PLA
synthesis, ring opening polymerization (ROP) of Lactide monomer is
one of the preferred methods. In the literature, the technique mainly
developed for ROP of PLA is based on metal/bimetallic catalyst (Sn,
Zn and Al) or other organic catalysts in suitable solvent. However,
the PLA synthesized using such catalysts may contain trace elements
of the catalyst which may cause toxicity. This work estimated the
usefulness and drawbacks of using different catalysts as well as effect
of alternative energies and future aspects for PLA production.
Abstract: The distribution networks are often exposed to harmful
incidents which can halt the electricity supply of the customer. In this
context, we studied a real case of a critical zone of the Tunisian
network which is currently characterized by the dysfunction of its
plan of protection. In this paper, we were interested in the
harmonization of the protection plan settings in order to ensure a
perfect selectivity and a better continuity of service on the whole of
the network.
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.