Abstract: In new energy development, wind power has boomed.
It is due to the proliferation of wind parks and their operation in
supplying the national electric grid with low cost and clean resources.
Hence, there is an increased need to establish a proactive
maintenance for wind turbine machines based on remote control and
monitoring. That is necessary with a real-time wireless connection in
offshore or inaccessible locations while the wired method has many
flaws. The objective of this strategy is to prolong wind turbine
lifetime and to increase productivity. The hardware of a remote
control and monitoring system for wind turbine parks is designed. It
takes advantage of GPRS or Wi-Max wireless module to collect data
measurements from different wind machine sensors through IP based
multi-hop communication. Computer simulations with Proteus ISIS
and OPNET software tools have been conducted to evaluate the
performance of the studied system. Study findings show that the
designed device is suitable for application in a wind park.
Abstract: Nations are still finding it quite difficult to win mega
sport competitions despite the major contribution of sport to society
in terms of social and economic development, personal health, and in
education. Even though the world of sports has been transformed into
a huge global economy, it is important to note that the first step of
sport is usually its introduction to children at school through physical
education or PE. In other words, nations who do not win mega sport
competitions also suffer from a weak and neglected PE system. This
problem of the neglect of PE systems is the main motivation of this
research aimed at examining the factors affecting the perceived
awareness of physical education teachers on the ICTs that are
adoptable for the teaching and learning of physical education. Two
types of research objectives will materialize this aim: relevant
theories will be identified in relation to the analysis of the perceived
ICT awareness of PE teachers and subsequent models will be
compiled and designed from existing literature; the empirical testing
of such theories and models will also be achieved through the survey
of PE teachers from the Camperdown magisterial district of the
KwaZulu-Natal province of South Africa. The main hypothesis at the
heart of this study is the relationship between the demographics of PE
teachers, their behavior both as individuals and as social entities, and
their perceived awareness of the ICTs that are adoptable for PE, as
postulated by existing literature; except that this study categorizes
human behavior under performance expectancy, computer attitude,
and social influence. This hypothesis was partially confirmed by the
survey conducted by this research in the sense that performance
expectancy and teachers’ age, gender, computer usage, and class size
were found to be the only factors affecting their awareness of ICTs
for physical education.
Abstract: The world wide web network is a network with a
complex topology, the main properties of which are the distribution
of degrees in power law, A low clustering coefficient and a weak
average distance. Modeling the web as a graph allows locating the
information in little time and consequently offering a help in the
construction of the research engine. Here, we present a model based
on the already existing probabilistic graphs with all the aforesaid
characteristics. This work will consist in studying the web in order to
know its structuring thus it will enable us to modelize it more easily
and propose a possible algorithm for its exploration.
Abstract: In order to study the effect of drought stress on grain
yield, yield components and associated traits of durum wheat
cultivars, an experiment was done as split plot arrangement using
randomized complete block design with three replications in Ilam
province, Iran in 2009-2010 cropping season. Different levels of
irrigation (Full irrigation, drought stress at stem elongation,
Flowering and grain formation stages) were considered as a main plot
and three durum wheat cultivars (Yavaros, Seimareh and Karkheh)
were assigned as a sub plot. The results showed that drought stress
was significant on grain yield, spike.m-2, grain. Spike-1, 1000-grain
weight, biological yield, harvest index and protein content. Drought
stress at all stages caused a loss in grain yield and its components.
Full irrigation had the highest grain yield and yield components.
Drought stress at stem elongation, flowering and grain formation
stages caused a reduction in spike.m-2, grain.spike-1 and 1000-grain
weight, respectively. Protein content was significantly affected by
drought stress. The highest protein content was obtained from
drought stress at grain formation stage. Cultivars had an influence on
grain yield and yield components. Yavaros and Seimareh cultivars
had the highest and lowest grain yield, respectively. Interaction effect
between drought stress and cultivar had a significant effect on grain
and yield components. Full irrigation and Yavaros cultivar had the
highest grain yield and drought stress at grain formation stage and
Seimareh cultivar had the lowest grain yield, respectively.
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: Different services based on different switching
techniques in wireless networks leads to drastic changes in the
properties of network traffic. Because of these diversities in services,
network traffic is expected to undergo qualitative and quantitative
variations. Hence, assumption of traffic characteristics and the
prediction of network events become more complex for the wireless
networks. In this paper, the traffic characteristics have been studied
by collecting traces from the mobile switching centre (MSC). The
traces include initiation and termination time, originating node, home
station id, foreign station id. Traffic parameters namely, call interarrival
and holding times were estimated statistically. The results
show that call inter-arrival and distribution time in this wireless
network is heavy-tailed and follow gamma distributions. They are
asymptotically long-range dependent. It is also found that the call
holding times are best fitted with lognormal distribution. Based on
these observations, an analytical model for performance estimation is
also proposed.
Abstract: In this paper a scheme is proposed for generating
a programmable current reference which can be implemented
in the CMOS technology. The current can be varied over a
wide range by changing an external voltage applied to one
of the control gates of FGMOS (Floating Gate MOSFET).
For a range of supply voltages and temperature, CMOS
current reference is found to be dependent, this dependence
is compensated by subtracting two current outputs with the
same dependencies on the supply voltage and temperature.
The system performance is found to improve with the
use of FGMOS. Mathematical analysis of the proposed
circuit is done to establish supply voltage and temperature
independence. Simulation and performance evaluation of the
proposed current reference circuit is done using TANNER
EDA Tools. The current reference shows the supply and
temperature dependencies of 520 ppm/V and 312 ppm/oC,
respectively. The proposed current reference can operate down
to 0.9 V supply.
Abstract: With advances in solid-state power electronic devices
and microprocessors, various pulse-width-modulation (PWM)
techniques have been developed for industrial applications. This
paper presents the comparison of two different PWM techniques, the
sinusoidal PWM (SPWM) technique and the space-vector PWM
(SVPWM) technique applied to two level VSI for micro grid
applications. These two methods are compared by discussing their
ease of implementation and by analyzing the output harmonic spectra
of various output voltages (line-to-neutral voltages, and line-to-line
voltages) and their total harmonic distortion (THD). The SVPWM
technique in the under-modulation region can increase the
fundamental output voltage by 15.5% over the SPWM technique.
Abstract: In this paper, numerical solution of system of
Fredholm and Volterra integral equations by means of the Spline
collocation method is considered. This approximation reduces the
system of integral equations to an explicit system of algebraic
equations. The solution is collocated by cubic B-spline and the
integrand is approximated by the Newton-Cotes formula. The error
analysis of proposed numerical method is studied theoretically. The
results are compared with the results obtained by other methods to
illustrate the accuracy and the implementation of our method.
Abstract: The current study explored the effect of economic
development, financial development and institutional quality on
environmental destruction in upper-middle income countries during
the time period of 1999-2011. The dependent variable is logarithm of
carbon dioxide emissions that can be considered as an index for
destruction or quality of the environment given to its effects on the
environment. Financial development and institutional development
variables as well as some control variables were considered. In order
to study cross-sectional correlation among the countries under study,
Pesaran and Friz test was used. Since the results of both tests show
cross-sectional correlation in the countries under study, seemingly
unrelated regression method was utilized for model estimation. The
results disclosed that Kuznets’ environmental curve hypothesis is
confirmed in upper-middle income countries and also, financial
development and institutional quality have a significant effect on
environmental quality. The results of this study can be considered by
policy makers in countries with different income groups to have
access to a growth accompanied by improved environmental quality.
Abstract: Microarray technology is universally used in the study
of disease diagnosis using gene expression levels. The main
shortcoming of gene expression data is that it includes thousands of
genes and a small number of samples. Abundant methods and
techniques have been proposed for tumor classification using
microarray gene expression data. Feature or gene selection methods
can be used to mine the genes that directly involve in the
classification and to eliminate irrelevant genes. In this paper
statistical measures like T-Statistics, Signal-to-Noise Ratio (SNR)
and F-Statistics are used to rank the genes. The ranked genes are used
for further classification. Particle Swarm Optimization (PSO)
algorithm and Shuffled Frog Leaping (SFL) algorithm are used to
find the significant genes from the top-m ranked genes. The Naïve
Bayes Classifier (NBC) is used to classify the samples based on the
significant genes. The proposed work is applied on Lung and Ovarian
datasets. The experimental results show that the proposed method
achieves 100% accuracy in all the three datasets and the results are
compared with previous works.
Abstract: The main goal of this paper was evaluate the effect of
diets containing different levels of probiotic on performance and milk
composition of lactating cows.
Eight Holstein cows were distributed in two 4x4 Latin square. The
diets were based on corn silage, concentrate and the treatment (0, 3, 6
or 9 grams of probiotic/animal/day). It was evaluated the dry matter
intake of nutrients, milk yield and composition.
The use of probiotics did not affect the nutrient intake (p>0.05)
neither the daily milk production or corrected to 4% fat (p>0.05).
However, it was observed that there was a significant fall in milk
composition with higher levels of probiotics supplementation.
These results emphasize the need of further studies with different
experimental designs or improve the number of Latin square with
longer periods of adaptation.
Abstract: In this paper family of multilevel inverter topology
with reduced number of power switches is presented. The proposed
inverter can generate both even and odd level. The proposed topology
is suitable for symmetric structure. The proposed symmetric inverter
results in reduction of power switches, power diode and gate driver
circuits and also it may further minimize the installation area and
cost. To prove the superiority of proposed topology is compared with
conventional topologies. The performance of this symmetric
multilevel inverter has been tested by computer based simulation and
prototype based experimental setup for nine-level inverter is
developed and results are verified.
Abstract: It’s an era of high competition, dynamism and
complexities which have forced organizations to change dramatically
due to rising customer expectations. Marketers are under constant
pressure to deliver finest to their customers. With the advent of
technology, marketers have identified latest advertising media
options to reach out to target audience. But the conventional ways of
print advertisements still holds a deeper penetration and coverage.
Various researchers and practitioners have studied the area of print
media advertising and have tried to identify and implement
advertisement effectiveness enablers. The purpose of this paper is to
suggest select enablers for print media in Indian context using an
integrated approach of review of literature and investigative
interviews with academicians and experts from the area of
advertising.
Abstract: The asynchronous discussion forum is one of the most
widely used activities in learning management system environment.
Online forum allows participants to interact, construct knowledge,
and can be used to complement face to face sessions in blended
learning courses. However, to what extent do the students perceive
the benefits or advantages of forum remain to be seen. Through
content and social network analyses, instructors will be able to gauge
the students’ engagement and knowledge construction level. Thus,
this study aims to analyze the students’ level of knowledge
construction and their participation level that occur through online
discussion. It also attempts to investigate the relationship between the
level of knowledge construction and their social interaction patterns.
The sample involves 23 students undertaking a master course in one
public university in Malaysia. The asynchronous discussion forum
was conducted for three weeks as part of the course requirement. The
finding indicates that the level of knowledge construction is quite
low. Also, the density value of 0.11 indicating the overall
communication among the participants in the forum is low. This
study reveals that strong and significant correlations between SNA
measures (in-degree centrality, out-degree centrality) and level of
knowledge construction. Thus, allocating these active students in
different group aids the interactive discussion takes place. Finally,
based upon the findings, some recommendations to increase students’
level of knowledge construction and also for further research are
proposed.
Abstract: Lately, asynchronous discussion forum is integrated in
higher educational institutions as it may increase learning process,
learners’ understanding, achievement and knowledge construction.
The asynchronous discussion forum is used to complement the
traditional, face-to-face learning session in hybrid learning courses.
However, studies have proven that students’ engagement in online
forums is still unconvincing. Thus, the aim of this study is to
investigate the motivating factors and obstacles that affect the
learners’ engagement in asynchronous discussion forum. This study
is carried out in one of the public higher educational institutions in
Malaysia with 18 postgraduate students as samples. The authors have
developed a 40-items questionnaire based on literature review. The
results indicate several factors that have encouraged or limited
students’ engagement in asynchronous discussion forum: (a) the
practices or behaviors of peers, or instructors, (b) the needs for the
discussions, (c) the learners’ personalities, (d) constraints in
continuing the discussion forum, (e) lack of ideas, (f) the level of
thoughts, (g) the level of knowledge construction, (h) technical
problems, (i) time constraints and (j) misunderstanding. This study
suggests some recommendations to increase the students’
engagement in online forums. Finally, based upon the findings, some
implications are proposed for further research.
Abstract: The sub-task pattern in terms of deviations and defects
should be identified and understood in order to improve the quality of
practices in construction projects. Therefore, sub-task susceptibility
to exposure to deviations and defects has been evaluated and
classified via six classifications proposed in this study. Thirty-four
case studies of specific sub-tasks (from compression members in
constructed concrete structures) were collected from seven
construction projects in order to examine the study’s proposed
classifications. The study revealed that the sub-task has a high
sensitivity to deviation, where 91% of the cases were recorded as
deviations; however, only 19% of cases were recorded as defects.
Other findings were that the actual work during the execution process
is a high source of deviation for this sub-task (74%), while only 26%
of the source of deviation was due to both design documentation and
the actual work. These findings significantly imply that the study’s
proposed classifications could be used to determine the pattern of
each sub-task and develop proactive actions to overcome issues of
sub-task deviations and defects.
Abstract: Off-site construction methods have played an
important role in the construction sector in the past few decades. It is
increasingly becoming a major alternative technique and strategic
direction compared to traditional in-situ method. It produces a
significant amount of value for the construction industry and the
economy more generally. To date, an impressive number of studies
have been lunched on the perceived perception of off-site
construction. However, it seems that a quantifying benefit on the
offsite construction area is lacking. Therefore, this paper examines
the recent research literature on the benefits of off- site construction
and provides future direction. In the beginning, this paper provides a
brief history and current value of the off-site construction followed
by a detailed discussion on the benefit of off-site construction. These
benefits include but not limited to time saving, quality improvement,
relieving skills shortages, cost reduction and productivity
improvement. Toward this end, off-site construction should learn
from other productive industry similar to services or manufacturing
industry by applying operational management tools and techniques
with extensive focus on employee empowerment will shed the light
on future uptake of Off-site construction. This study is of value in
providing scholars have a clear picture of perceived benefit of off-site
construction research and give an opportunities for future uptake of
off-site method.
Abstract: Life Cycle Cost (LCC) is one of the goals and key
pillars of the construction management science because it comprises
many of the functions and processes necessary, which assist
organisations and agencies to achieve their goals. It has therefore
become important to design and control assets during their whole life
cycle, from the design and planning phase through to disposal phase.
LCCA is aimed to improve the decision making system in the
ownership of assets by taking into account all the cost elements
including to the asset throughout its life.
Current application of LCC approach is impractical during
misunderstanding of the advantages of LCC. This main objective of
this research is to show a different relationship between capital cost
and long-term running costs. One hundred and thirty eight actual
building projects in United Kingdom (UK) were used in order to
achieve and measure the above-mentioned objective of the study. The
result shown that LCC is one of the most significant tools should be
considered on the decision making process.
Abstract: This experimental study aims at studying the
conversion of macro-algae into bioethanol under several steps of
procedure: preparation, pre-treatment, fermentation, and distillation.
The main objective of this work was to investigate the role of buffer’s
type as a stabiliser of pH level and fermentation time on the yield of
ethanol. For this purpose, experiments were carried out on biomass
macro-algae to de-couple the pre-treatment and fermentation
processes from those associated with distillation process. β-
glucosidase was used as cellulose decomposer during hydrolysis step
and yeast was used during fermentation process. The species of
macro-algae utilised as energy feedstock was Ulva lactuca and it was
harvested from southern coast of Central of Java Island – Indonesia.
Experiments were conducted in a simple fermenter over a different
buffer: citrate buffer and acetic buffer, and over a range of
fermentation times between 5 to 20 days. The ethanol production was
found to be significantly affected by both variables. The optimum
time of fermentation was 10 days with citrate buffer; result in
0.88458% of ethanol, and the ethanol content after distillation
process was shown 0.985015%.