Abstract: Numerical study of the static response of
homogeneous clay stratum considering a wide range of cohesion and
subject to foundation loads is presented. The linear elastic–perfectly
plastic constitutive relation with the von Mises yield criterion were
utilised to develop a numerically cost effective finite element model
for the soil while imposing a rigid body constrain to the foundation
footing. From the analyses carried out, estimate of the bearing
capacity factor, Nc as well as the ultimate load-carrying capacities of
these soils, effect of cohesion on foundation settlements, stress fields
and failure propagation were obtained. These are consistent with
other findings in the literature and hence can be a useful guide in
design of safe foundations in clay soils for buildings and other
structure.
Abstract: Lagos urban mini bus drivers play a critical role in the
transportation sector. The current major mode of transportation
within Lagos metropolis remains road transportation and this
confirms the relevance of urban mini-bus drivers in transporting the
populace to their various destinations. Other modes of transportation
such as the train and waterways are currently inadequate. Various
threats to the well-being of urban bus drivers include congested
traffic typical of modern day lifestyles, dwindling financial returns
due to long hours in traffic, fewer hours of sleep, inadequate diet,
time pressure, and assaults related to fare disputes. Several healthrelated
problems have been documented to be associated with urban
bus driving. For instance, greater rates of hypertension, obesity and
cholesterol level have been reported. Research studies are yet to
identify the influence of age and marital status on the well-being of
urban mini-bus drivers in Lagos metropolis. A study of this nature is
necessary as it is culturally perceived in Nigeria that older and
married people are especially influenced by family affiliation and
would behave in ways that would project positive outcomes. The
study sample consisted of 150 urban mini-bus drivers who were
conveniently sampled from six (6) different terminuses where their
journey begins and terminates. The well-being questionnaire was
administered to participants. The criteria for inclusion in the study
included the ability to read in English language and the confirmation
that interested participants were on duty and suited to be driving
mini-buses. Due to the nature of the job of bus driving, the researcher
administered the questionnaires on participants who were free and
willing to respond to the survey. All participants were males of
various age groups and of different marital statuses. Results of
analyses conducted revealed no significant influence of age and
marital status on the well-being of urban mini-bus drivers. This
indicates that the well-being of urban mini bus drivers is not
influenced by age or marital status. The findings of this study have
cultural implications. It negates the popularly held belief that older
and married people care more about their well-being than younger
and single people. It brings to fore the need to also identify and
consider other factors when certifying people for the job of urban bus
driving.
Abstract: Highly developed technology and highly competitive
global market highlight the important role of competitive advantages
and operation performances in sustainable company operation.
Activity-Based Costing (ABC) provides accurate operation cost and
operation performance information. Rich literatures provide relevant
research with cases study on Activity-Based Costing application, but
the research on cause relationship between key success factors and its
specific outcome, such as profitability or share market are few. These
relationships provide the ways to handle the key success factors to
achieve the specific outcomes for ensuring to promote the competitive
advantages and operation performances. The main purposes of this
research are exploring the key success paths by Key Success Paths
approach which will lead the ways to apply Activity-Base Costing.
The Key Success Paths is the innovative method which is exploring
the cause relationships and explaining what are the effects of key
success factors to specific outcomes of Activity-Based Costing
implementation. The cause relationships between key success factors
and successful specific outcomes are Key Success Paths (KSPs). KSPs
are the guidelines to lead the cost management strategies to achieve the
goals of competitive advantages and operation performances. The
research findings indicate that good management system design may
affect the well outcomes of Activity-Based Costing application and
achieve to outstanding competitive advantage, operating performance
and profitability as well by KSPs exploration.
Abstract: Recovering resources from water purification sludge
(WPS) have been gradually stipulated in environmental protection
laws and regulations in many nations. Hence, reusing the WPS is
becoming an important topic, and recovering alum from WPS is one of
the many practical alternatives. Most previous research efforts have
been conducted on studying the amphoteric characteristic of aluminum
hydroxide for investigating the optimum pH range to dissolve the
Al(III) species from WPS, but it has been lack of reaction kinetics or
mechanisms related discussion. Therefore, in this investigation, water
purification sludge (WPS) solution was broken by ultrasound to make
particle size of reactants smaller, specific surface area larger.
According to the reaction kinetics, these phenomena let the dissolved
aluminum salt quantity increased and the reaction rate go faster.
Abstract: This paper discusses the thematic structure of Yoruba
popular music of Southwest Nigeria. It examines the use of themes
and variations in early and contemporary Juju music. The work is an
outcome of a research developed by the author in his doctoral studies
at the University of Lagos, Nigeria, with the aim of analyzing the
thematic and motivic developments in Yoruba popular genres.
Observations, interviews, live recordings and CDs were used as
methods for eliciting information. Field recordings and CDs of
selected musical samples were also transcribed and notated. The
research established the prevalent use of string of themes by Juju
musicians as a compositional technique in moving from one musical
section to another, as they communicate the verbal messages in their
song. These themes consist of the popular ‘call and response’ form
found in most African music, analogous to the western ‘subject and
answer’ style of the fugue or sonata form, although without the tonic–
dominant relations. Due to the short and repetitive form of African
melodies and rhythms, a theme is restated as a variation, where its
rhythmic and melodic motifs are stylistically developed and repeated,
but still retaining its recognizable core musical structure. The
findings of this study showed that Juju musicians generally often
employ a thematic plan where new themes are used to arrange the
songs into sections, and each theme is developed into variations in
order to further expand the music, eliminate monotony, and create
musical aesthetics, serving as hallmark of its musical identity. The
study established the musical and extra-musical attributes of the
genre, while recommending further research towards analyzing the
various compositional techniques employed in African popular
genres.
Abstract: A solar receiver is designed for operation under
extremely uneven heat flux distribution, cyclic weather, and cloud
transient cycle conditions, which can include large thermal stress and
even receiver failure. In this study, the effect of different oil velocity
on convection coefficient factor and impact of wind velocity on local
Nusselt number by Finite Volume Method will be analyzed. This
study is organized to give an overview of the numerical modeling
using a MATLAB software, as an accurate, time efficient and
economical way of analyzing the heat transfer trends over stationary
receiver tube for different Reynolds number. The results reveal when
oil velocity is below 0.33m/s, the value of convection coefficient is
negligible at low temperature. The numerical graphs indicate that
when oil velocity increases up to 1.2 m/s, heat convection coefficient
increases significantly. In fact, a reduction in oil velocity causes a
reduction in heat conduction through the glass envelope. In addition,
the different local Nusselt number is reduced when the wind blows
toward the concave side of the collector and it has a significant effect
on heat losses reduction through the glass envelope.
Abstract: The fundamental issue in understanding the origin and
growth mechanism of nanomaterials, from a fundamental unit is a big
challenging problem to the scientists. Recently, an immense attention
is generated to the researchers for prediction of exceptionally stable
atomic cluster units as the building units for future smart materials.
The present study is a systematic investigation on the stability and
electronic properties of a series of bimetallic (semiconductor-alkaline
earth) clusters, viz., BxMg3 (x=1-5) is performed, in search for
exceptional and/ or unusual stable motifs. A very popular hybrid
exchange-correlation functional, B3LYP along with a higher basis
set, viz., 6-31+G[d,p] is employed for this purpose under the density
functional formalism. The magic stability among the concerned
clusters is explained using the jellium model. It is evident from the
present study that the magic stability of B4Mg3
cluster arises due to
the jellium shell closure.
Abstract: At a global level, water stewardship, water stress and
water security are crucial factors in tourism planning and
development considerations. Challenges associated with water is of
particular concern to the Maldives as there is limited availability of
freshwater, high dependency on desalinated water, and high unit cost
associated with desalinating water. While the Maldives is promoted
as an example of sustainable tourism, a key sustainability challenge
facing tourism dependent communities is the efficient use and
management of available water resources. A water crisis event in the
capital island of Maldives highlighted how precarious water related
issues are in this tourism dependent destination. Applying
netnography, the focus of this working paper is to present community
perceptions of how government policies addressed Malé Water and
Sewerage Company (MWSC) water crisis event.
Abstract: It is quite essential to investigate the causes of
pavement deterioration in order to select the proper maintenance
technique. The objective of this study was to identify factors cause
deterioration of recently constructed roads in Khartoum state. A
comprehensive literature concerning the factors of road deterioration,
common road defects and their causes were reviewed. Three major
road projects with different deterioration reasons were selected for
this study. The investigation involved field survey and laboratory
testing on those projects to examine the existing pavement
conditions. The results revealed that the roads investigated
experienced severe failures in the forms of cracks, potholes, and
rutting in the wheel path. The causes of those failures were found
mainly linked to poor drainage, traffic overloading, expansive
subgrade soils, and the use of low quality materials in construction.
Based on the results, recommendations were provided to help
highway engineers in selecting the most effective repair techniques
for specific kinds of distresses.
Abstract: Unemployment among the youth is a significant
problem in South Africa. Large corporations and the public sector
simply cannot create enough jobs. Too many youths in South Africa
currently do not consider entrepreneurship as an option in order to
become independent. Unlike the youth of the Netherlands, South
African youth prefer to find employment in the public or private
sector. The Netherlands has a much lower unemployment rate than
South Africa and the Dutch are generally very entrepreneurial. From
early on, entrepreneurship is considered a desirable career option in
the Netherlands. The purpose of this study was to determine whether
there is a difference in the perceptions of some Dutch and South
African students in terms of unemployment and entrepreneurship.
Questionnaires were distributed to students at the North West
University's Vaal Triangle campus in Vanderbijlpark in Gauteng,
South Africa and the Technical University of Delft in the
Netherlands. A descriptive statistical analysis approach was followed
and the means for the independent questions were calculated. The
results demonstrate that the Dutch students are not as concerned
about unemployment after completion of their studies as this is not as
significant a problem as it is in South Africa. Both groups had
positive responses towards the posed questions, but the South African
group felt more strongly about the issues. Both groups of students felt
that there was a need for more practical entrepreneurship training.
The South African education system should focus on practical
entrepreneurship training from a young age.
Abstract: Globally, many women are still disadvantaged when it
comes to business opportunities. Entrepreneurship development
programs, specifically designed to assist women entrepreneurs, are
assisting in solving this problem to a certain extent. The purpose of
this study is to identify the factors that motivate females to start their
own business. Females, from three different groups (2013, 2014 and
2015), who were all enrolled in a short learning program specifically
designed for women in early start-up stage or intending to start a
business, were asked what motivated them to start a business. The
results indicated that, from all three groups, the majority of the
women wanted to start a business to be independent and have
freedom and to add towards a social goal. The results further
indicated that in general, women would enter into entrepreneurship
activity due to pull factors rather than push factors.
Abstract: A Multi-dimensional computational fluid dynamics
(CFD) two-phase model was developed with the aim to simulate
the in-core coolant circuit of a pressurized heavy water reactor
(PHWR) of a commercial nuclear power plant (NPP). Due to the
fact that this PHWR is a Reactor Pressure Vessel type (RPV),
three-dimensional (3D) detailed modelling of the large reservoirs of
the RPV (the upper and lower plenums and the downcomer) were
coupled with an in-house finite volume one-dimensional (1D) code
in order to model the 451 coolant channels housing the nuclear fuel.
Regarding the 1D code, suitable empirical correlations for taking into
account the in-channel distributed (friction losses) and concentrated
(spacer grids, inlet and outlet throttles) pressure losses were used.
A local power distribution at each one of the coolant channels
was also taken into account. The heat transfer between the coolant
and the surrounding moderator was accurately calculated using a
two-dimensional theoretical model. The implementation of subcooled
boiling and condensation models in the 1D code along with the use
of functions for representing the thermal and dynamic properties of
the coolant and moderator (heavy water) allow to have estimations
of the in-core steam generation under nominal flow conditions for a
generic fission power distribution. The in-core mass flow distribution
results for steady state nominal conditions are in agreement with the
expected from design, thus getting a first assessment of the coupled
1/3D model. Results for nominal condition were compared with
those obtained with a previous 1/3D single-phase model getting more
realistic temperature patterns, also allowing visualize low values of
void fraction inside the upper plenum. It must be mentioned that the
current results were obtained by imposing prescribed fission power
functions from literature. Therefore, results are showed with the aim
of point out the potentiality of the developed model.
Abstract: In order to be competitive, companies have to reduce
their production costs while meeting increasing quality requirements.
Therefore, companies try to plan their assembly processes as detailed
as possible. However, increasing product individualization leading to
a higher number of variants, smaller batch sizes and shorter product
life cycles raise the question to what extent the effort of detailed
planning is still justified. An important approach in this field of
research is the concept of determining the economic planning depth
for assembly process planning based on production specific
influencing factors. In this paper first solution hypotheses as well as a
first draft of the resulting method will be presented.
Abstract: The use of solar energy as a source for pumping water
is one of the promising areas in the photovoltaic (PV) application.
The energy of photovoltaic pumping systems (PVPS) can be widely
improved by employing an MPPT algorithm. This will lead
consequently to maximize the electrical motor speed of the system.
This paper presents a modified incremental conductance (IncCond)
MPPT algorithm with direct control method applied to a standalone
PV pumping system. The influence of the algorithm parameters on
system behavior is investigated and compared with the traditional
(INC) method. The studied system consists of a PV panel, a DC-DC
boost converter, and a PMDC motor-pump. The simulation of the
system by MATLAB-SIMULINK is carried out. Simulation results
found are satisfactory.
Abstract: In this study, static and dynamic responses of a typical
reinforced concrete solid slab, designed to British Standard (BS 8110:
1997) and under self and live loadings for dance halls are reported.
Linear perturbation analysis using finite element method was
employed for modal, impulse loading and frequency response
analyses of the slab under the aforementioned loading condition.
Results from the static and dynamic analyses, comprising of the slab
fundamental frequencies and mode shapes, dynamic amplification
factor, maximum deflection, stress distributions among other
valuable outcomes are presented and discussed. These were gauged
with the limiting provisions in the design code with a view of
justifying valid optimization objective function for the structure that
can ensure both adequate strength and economical section for large
clear span slabs. This is necessary owing to the continued increase in
cost of erecting building structures and the squeeze on public finance
globally.
Abstract: The education sector is constantly faced with rapid
changes in technologies in terms of ensuring that the curriculum is up
to date and in terms of making sure that students are aware of these
technological changes. This challenge can be seen as the motivation
for this study, which is to examine the factors affecting computing
students’ awareness of the latest Information Technologies (ICTs).
The aim of this study is divided into two sub-objectives which are:
the selection of relevant theories and the design of a conceptual
model to support it as well as the empirical testing of the designed
model. The first objective is achieved by a review of existing
literature on technology adoption theories and models. The second
objective is achieved using a survey of computing students in the four
universities of the KwaZulu-Natal province of South Africa. Data
collected from this survey is analyzed using Statistical package for
the Social Science (SPSS) using descriptive statistics, ANOVA and
Pearson correlations. The main hypothesis of this study is that there is
a relationship between the demographics and the prior conditions of
the computing students and their awareness of general ICT trends and
of Digital Switch Over (DSO) a new technology which involves the
change from analog to digital television broadcasting in order to
achieve improved spectrum efficiency. The prior conditions of the
computing students that were considered in this study are students’
perceived exposure to career guidance and students’ perceived
curriculum currency. The results of this study confirm that gender,
ethnicity, and high school computing course affect students’
perceived curriculum currency while high school location affects
students’ awareness of DSO. The results of this study also confirm
that there is a relationship between students prior conditions and their
awareness of general ICT trends and DSO in particular.
Abstract: A retrospective study conducted at Christian Medical
College (CMC) Teaching Hospital, Vellore, India on 14th August
2014 to assess the accuracy of clinically estimated foetal weight upon
labour admission. Estimating foetal weight is a crucial factor in
assessing maternal and foetal complications during and after labour.
Medical notes of ninety-eight postnatal women who fulfilled the
inclusion criteria were studied to evaluate the correlation between
their recorded Estimated Foetal Weight (EFW) on admission and
actual birth weight (ABW) of the newborn after delivery. Data
concerning maternal and foetal demographics was also noted.
Accuracy was determined by absolute percentage error and
proportion of estimates within 10% of ABW. Actual birth weights
ranged from 950-4080g. A strong positive correlation between EFW
and ABW (r=0.904) was noted. Term deliveries (≥40 weeks) in the
normal weight range (2500-4000g) had a 59.5% estimation accuracy
(n=74) compared to pre-term (4000g) were underestimated by 25% (n=3) and low birthweight
(LBW) babies were overestimated by 12.7% (n=9). Registrars who
estimated foetal weight were accurate in babies within normal weight
ranges. However, there needs to be an improvement in predicting
weight of macrosomic and LBW foetuses. We have suggested the use
of an amended version of the Johnson’s formula for the Indian
population for improvement and a need to re-audit once
implemented.
Abstract: As computing technology advances, smartphone
applications can assist student learning in a pervasive way. For
example, the idea of using mobile apps for the PA Common Trees,
Pests, Pathogens, in the field as a reference tool allows middle school
students to learn about trees and associated pests/pathogens without
bringing a textbook. While working on the development of three heterogeneous mobile
apps, we ran into numerous challenges. Both the traditional waterfall
model and the more modern agile methodologies failed in practice.
The waterfall model emphasizes the planning of the duration for each
phase. When the duration of each phase is not consistent with the
availability of developers, the waterfall model cannot be employed.
When applying Agile Methodologies, we cannot maintain the high
frequency of the iterative development review process, known as
‘sprints’. In this paper, we discuss the challenges and solutions. We
propose a hybrid model known as the Relay Race Methodology to
reflect the concept of racing and relaying during the process of
software development in practice. Based on the development project,
we observe that the modeling of the relay race transition between any
two phases is manifested naturally. Thus, we claim that the RRM
model can provide a de fecto rather than a de jure basis for the core
concept in the software development model. In this paper, the background of the project is introduced first.
Then, the challenges are pointed out followed by our solutions.
Finally, the experiences learned and the future works are presented.
Abstract: Polycyclic Aromatic Hydrocarbons (PAHs) are
formed mainly because of incomplete combustion of organic
materials during industrial, domestic activities or natural occurrence.
Their toxicity and contamination of terrestrial and aquatic ecosystem
have been established. However, with limited validity index, previous
research has focused on PAHs isomer pair ratios of variable
physicochemical properties in source identification. The objective of
this investigation was to determine the empirical validity of Pearson
Correlation Coefficient (PCC) and Cluster Analysis (CA) in PAHs
source identification along soil samples of different land uses.
Therefore, 16 PAHs grouped, as Endocrine Disruption Substances
(EDSs) were determined in 10 sample stations in top and sub soils
seasonally. PAHs was determined the use of Varian 300 gas
chromatograph interfaced with flame ionization detector. Instruments
and reagents used are of standard and chromatographic grades
respectively. PCC and CA results showed that the classification of
PAHs along pyrolitic and petrogenic organics used in source
signature is about the predominance PAHs in environmental matrix.
Therefore, the distribution of PAHs in the studied stations revealed
the presence of trace quantities of the vast majority of the sixteen
PAHs, which may ultimately inhabit the actual source signature
authentication. Therefore, factors to be considered when evaluating
possible sources of PAHs could be; type and extent of bacterial
metabolism, transformation products/substrates, and environmental
factors such as salinity, pH, oxygen concentration, nutrients, light
intensity, temperature, co-substrates, and environmental medium are
hereby recommended as factors to be considered when evaluating
possible sources of PAHs.
Abstract: Paper deals with the modeling and simulation of energy consumption and GHG production of two different modes of regional passenger transport – road and railway. These two transport modes use the same type of fuel – diesel. Modeling and simulation of the energy consumption in transport is often used due to calculation satisfactory accuracy and cost efficiency. Paper deals with the calculation based on EN standards and information collected from technical information from vehicle producers and characteristics of tracks. Calculation included maximal theoretical capacity of bus and train and real passenger’s measurement from operation. Final energy consumption and GHG production is calculated by using software simulation. In evaluation of the simulation is used system “well to wheel”.