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: Chatter vibrations, occurring during cutting process,
cause vibration between the cutting tool and workpiece, which
deteriorates surface roughness and reduces tool life. The purpose of
this study is to investigate the influence of cutting parameters and
tool construction on surface roughness and vibration in turning of
aluminum alloy AA2024. A new design of cutting tool is proposed,
which is filled up with epoxy granite in order to improve damping
capacity of the tool. Experiments were performed at the lathe using
carbide cutting insert coated with TiC and two different cutting tools
made of AISI 5140 steel. Taguchi L9 orthogonal array was applied to
design of experiment and to optimize cutting conditions. By the help
of signal-to-noise ratio and analysis of variance the optimal cutting
condition and the effect of the cutting parameters on surface
roughness and vibration were determined. Effectiveness of Taguchi
method was verified by confirmation test. It was revealed that new
cutting tool with epoxy granite has reduced vibration and surface
roughness due to high damping properties of epoxy granite in
toolholder.
Abstract: The practical efficient approach is suggested for
estimation of the seismoacoustic sources energy in C-OTDR
monitoring systems. This approach is represents the sequential plan
for confidence estimation both the seismoacoustic sources energy, as
well the absorption coefficient of the soil. The sequential plan
delivers the non-asymptotic guaranteed accuracy of obtained
estimates in the form of non-asymptotic confidence regions with
prescribed sizes. These confidence regions are valid for a finite
sample size when the distributions of the observations are unknown.
Thus, suggested estimates are non-asymptotic and nonparametric,
and also these estimates guarantee the prescribed estimation accuracy
in form of prior prescribed size of confidence regions, and prescribed
confidence coefficient value.
Abstract: High Performance Liquid Chromatography (HPLC)
method was developed and validated for simultaneous estimation of
6-Gingerol(6G) and 6-Shogaol(6S) in joint pain relief gel containing
ginger extract. The chromatographic separation was achieved by
using C18 column, 150 x 4.6mm i.d., 5μ Luna, mobile phase
containing acetonitrile and water (gradient elution). The flow rate
was 1.0 ml/min and the absorbance was monitored at 282 nm. The
proposed method was validated in terms of the analytical parameters
such as specificity, accuracy, precision, linearity, range, limit of
detection (LOD), limit of quantification (LOQ), and determined
based on the International Conference on Harmonization (ICH)
guidelines. The linearity ranges of 6G and 6S were obtained over 20-
60 and 6-18 μg/ml respectively. Good linearity was observed over the
above-mentioned range with linear regression equation Y= 11016x-
23778 for 6G and Y = 19276x-19604 for 6S (x is concentration of
analytes in μg/ml and Y is peak area). The value of correlation
coefficient was found to be 0.9994 for both markers. The limit of
detection (LOD) and limit of quantification (LOQ) for 6G were
0.8567 and 2.8555 μg/ml and for 6S were 0.3672 and 1.2238 μg/ml
respectively. The recovery range for 6G and 6S were found to be
91.57 to 102.36 % and 84.73 to 92.85 % for all three spiked levels.
The RSD values from repeated extractions for 6G and 6S were 3.43
and 3.09% respectively. The validation of developed method on
precision, accuracy, specificity, linearity, and range were also
performed with well-accepted results.
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: The increase of technogenic and natural accidents,
accompanied by air pollution, for example, by combustion products,
leads to the necessity of respiratory protection. This work is devoted to the development of a calorimetric method
and a device which allows investigating quickly the kinetics of
carbon dioxide sorption by chemisorbents on the base of potassium
superoxide in order to assess the protective properties of respiratory
protective closed circuit apparatus. The features of the traditional approach for determining the
sorption properties in a thin layer of chemisorbent are described, as
well as methods and devices, which can be used for the sorption
kinetics study. The authors developed an approach (as opposed to the traditional
approach) based on the power measurement of internal heat sources
in the chemisorbent layer. The emergence of the heat sources is a
result of exothermic reaction of carbon dioxide sorption. This
approach eliminates the necessity of chemical analysis of samples
and can significantly reduce the time and material expenses during
chemisorbents testing. Error of determining the volume fraction of adsorbed carbon
dioxide by the developed method does not exceed 12%. Taking into
account the efficiency of the method, we consider that it is a good
alternative to traditional methods of chemical analysis under the
assessment of the protection sorbents quality.
Abstract: Effective internal control system in the bursary unit of
tertiary educational institutions is geared toward achieving quality
teaching, learning and research environment and as well assist the
management of the institutions, particularly when decisions are to be
made. While internal control system exists in all institutions, the
outlined objectives above are far from being achieved. The paper
therefore assesses the effectiveness of internal control system in
tertiary educational institutions in Nasarawa State, Nigeria with
specific focus on the Nasarawa State Polytechnic, Lafia. The study is
survey, hence a simple closed ended questionnaire was developed
and administered to a sample of twenty seven (27) member staff from
the Bursary and the Internal audit unit of the Nasarawa State
Polytechnic, Lafia so as to obtain data for analysis purposes and to
test the study hypothesis. Responses from the questionnaire were
analysed using a simple percentage and chi square. Findings shows
that the right people are not assigned to the right job in the
department, budget, and management accounting were never used in
the institution’s operations and checking of subordinate by their
superior officers is not regular. This renders the current internal
control structure of the Polytechnic as ineffective and weak. The
paper therefore recommends that: transparency should be seen as
significant, as the institution work toward meeting its objectives, it
therefore means that the right staff be assigned the right job and
regular checking of the subordinates by their superiors be ensued.
Abstract: The paper will focus on the strategic development
deriving from the evolution of the traditional courtyard spatial
organization towards a new, contemporary sustainable way of living.
New sustainable approaches that engulf the social issues, the notion
of place, the understanding of weather architecture blended together
with the bioclimatic behavior will be seen through a series of
experimental case studies in the island of Cyprus, inspired and
originated from its traditional wisdom, ranging from small scale of
living to urban interventions. Weather and nature will be seen as co-architectural authors with
architects. Furthermore, the building will be seen not as an object but
rather as a vessel of human activities. This will further enhance the
notion of merging the material and immaterial, the built and unbuilt,
subject-human, and the object-building. This eventually will enable
to generate the discussion of the understanding of the building in
relation to the place and its inhabitants, where the human topography
is more important than the material topography. The specificities of
the divided island and the dealing with sites that are in vicinity with
the diving Green Line will further trigger explorations dealing with
the regeneration issues and the social sustainability offering
unprecedented opportunities for innovative sustainable ways of
living. Opening up a discourse with premises of weather-nature, materialimmaterial,
human-material topographies in relation to the contested
sites of the borders will lead us to develop innovative strategies for a
profound, both technical and social sustainability, which fruitfully
yields to innovative living built environments, responding to the ever
changing environmental and social needs. As a starting point, a case study in Kaimakli in Nicosia, a
refurbishment with an extension of a traditional house, already
engulfs all the traditional/ vernacular wisdom of the bioclimatic
architecture. The project focusses on the direct and quite obvious
bioclimatic features such as south orientation and cross ventilation.
Furthermore, it tries to reinvent the adaptation of these parameters in
order to turn the whole house to a contemporary living environment.
In order to succeed this, evolutions of traditional architectural
elements and spatial conditions are integrated in a way that does not
only respond to some certain weather conditions, but they integrate
and blend the weather within the built environment. A series of
innovations aiming at maximum flexibility is proposed. The house
can finally be transformed into a winter enclosure, while for the most
part of the year it turns into a ‘camping’ living environment. Parallel to experimental interventions in existing traditional units,
we will proceed examining the implementation of the same
developed methodology in designing living units and complexes.
Malleable courtyard organizations that attempt to blend the
traditional wisdom with the contemporary needs for living, the
weather and nature with the built environment will be seen tested in
both horizontal and vertical developments. Social activities are seen as directly affected and forged by the
weather conditions thus generating a new social identity of people where people are directly involved and interacting with the weather.
The human actions and interaction with the built, material
environment in order to respond to weather will be seen as the result
of balancing the social with the technological sustainability, the
immaterial, and the material aspects of the living environment.
Abstract: Internal circulation two-platen clamping system for
injection molding machine (IMM) has many potential advantages on
energy-saving. In order to estimate its properties, experiments were
carried out in this paper. Displacement and pressure of the components
were measured. In comparison, the model of hydraulic clamping
system was established by using AMESim. The related parameters as
well as the energy consumption could be calculated. According to the
analysis, the hydraulic system was optimized in order to reduce the
energy consumption.
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: Background: Maintaining the correct body balance is
essential in the prevention of falls in the elderly, which is especially
important for women because of postmenopausal osteoporosis and
the serious consequences of falls. One of the exercise methods which
is very popular among adults, and which may affect body balance in
the positive way is the Pilates method. The aim of the study was to
evaluate the effect of regular Pilates exercises on the ability to
maintain body balance in static conditions in adult healthy women.
Material and methods: The study group consisted of 20 healthy
women attending Pilates twice a week for at least 1 year. The control
group consisted of 20 healthy women physically inactive. Women in
the age range from 35 to 50 years old without pain in musculoskeletal
system or other pain were only qualified to the groups. Body balance
was assessed using MatScan VersaTek platform with Sway Analysis
Module based on Matscan Clinical 6.7 software (Tekscan Inc.,
U.S.A). The balance was evaluated under the following conditions:
standing on both feet with eyes open, standing on both feet with eyes
closed, one-leg standing (separately on the right and left foot) with
eyes open. Each test lasted 30 seconds. The following parameters
were calculated: estimated size of the ellipse of 95% confidence, the
distance covered by the Center of Gravity (COG), the size of the
maximum shift in the sagittal and frontal planes and load distribution
between the left and right foot, as well as between rear- and forefoot.
Results: It was found that there is significant difference between the
groups in favor of the study group in the size of the confidence
ellipse and maximum shifts of COG in the sagittal plane during
standing on both feet, both with the eyes open and closed (p
Abstract: Introduction: Whole-Body Vibration (WBV) uses
high frequency mechanical stimuli generated by a vibration plate and
transmitted through bone, muscle and connective tissues to the whole
body. Research has shown that long-term vibration-plate training
improves neuromuscular facilitation, especially in afferent neural
pathways, responsible for the conduction of vibration and
proprioceptive stimuli, muscle function, balance and proprioception.
Some researchers suggest that the vibration stimulus briefly inhibits
the conduction of afferent signals from proprioceptors and can
interfere with the maintenance of body balance. The aim of this study
was to evaluate the influence of a single set of exercises associated
with whole-body vibration on the joint position sense and body
balance. Material and methods: The study enrolled 55 people aged
19-24 years. These individuals were randomly divided into a test
group (30 persons) and a control group (25 persons). Both groups
performed the same set of exercises on a vibration plate. The
following vibration parameters: frequency of 20Hz and amplitude of
3mm, were used in the test group. The control group performed
exercises on the vibration plate while it was off. All participants were
instructed to perform six dynamic exercises lasting 30 seconds each
with a 60-second period of rest between them. The exercises involved
large muscle groups of the trunk, pelvis and lower limbs.
Measurements were carried out before and immediately after
exercise. Joint position sense (JPS) was measured in the knee joint
for the starting position at 45° in an open kinematic chain. JPS error
was measured using a digital inclinometer. Balance was assessed in a
standing position with both feet on the ground with the eyes open and
closed (each test lasting 30 sec). Balance was assessed using Matscan
with FootMat 7.0 SAM software. The surface of the ellipse of
confidence and front-back as well as right-left swing were measured
to assess balance. Statistical analysis was performed using Statistica
10.0 PL software. Results: There were no significant differences
between the groups, both before and after the exercise (p> 0.05). JPS
did not change in both the test (10.7° vs. 8.4°) and control groups
(9.0° vs. 8.4°). No significant differences were shown in any of the
test parameters during balance tests with the eyes open or closed in
both the test and control groups (p> 0.05). Conclusions: 1.
Deterioration in proprioception or balance was not observed
immediately after the vibration stimulus. This suggests that vibrationinduced
blockage of proprioceptive stimuli conduction can have only
a short-lasting effect that occurs only as long as a vibration stimulus
is present. 2. Short-term use of vibration in treatment does not impair
proprioception and seems to be safe for patients with proprioceptive
impairment. 3. These results need to be supplemented with an
assessment of proprioception during the application of vibration
stimuli. Additionally, the impact of vibration parameters used in the
exercises should be evaluated.
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: 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: 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 laser-ultrasonic method is realized for
quantifying the influence of porosity on the local Young’s
modulus of isotropic composite materials. The method is based on
a laser thermooptical method of ultrasound generation combined
with measurement of the phase velocity of longitudinal and shear
acoustic waves in samples. The main advantage of this method
compared with traditional ultrasonic research methods is the
efficient generation of short and powerful probing acoustic pulses
required for reliable testing of ultrasound absorbing and
scattering heterogeneous materials. Using as an example samples
of a metal matrix composite with reinforcing microparticles of
silicon carbide in various concentrations, it is shown that to
provide an effective increase in Young’s modulus with increasing
concentration of microparticles, the porosity of the final sample
should not exceed 2%.
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: Large-scale machine tools for the manufacturing of
large work pieces, e.g. blades, casings or gears for wind turbines,
feature pose-dependent dynamic behavior. Small structural damping
coefficients lead to long decay times for structural vibrations that
have negative impacts on the production process. Typically, these
vibrations are handled by increasing the stiffness of the structure by
adding mass. This is counterproductive to the needs of sustainable
manufacturing as it leads to higher resource consumption both in
material and in energy. Recent research activities have led to higher
resource efficiency by radical mass reduction that is based on controlintegrated
active vibration avoidance and damping methods. These
control methods depend on information describing the dynamic
behavior of the controlled machine tools in order to tune the
avoidance or reduction method parameters according to the current
state of the machine. This paper presents the appearance, consequences and challenges
of the pose-dependent dynamic behavior of lightweight large-scale
machine tool structures in production. It starts with the theoretical
introduction of the challenges of lightweight machine tool structures
resulting from reduced stiffness. The statement of the pose-dependent
dynamic behavior is corroborated by the results of the experimental
modal analysis of a lightweight test structure. Afterwards, the
consequences of the pose-dependent dynamic behavior of lightweight
machine tool structures for the use of active control and vibration
reduction methods are explained. Based on the state of the art of
pose-dependent dynamic machine tool models and the modal
investigation of an FE-model of the lightweight test structure, the
criteria for a pose-dependent model for use in vibration reduction are
derived. The description of the approach for a general posedependent
model of the dynamic behavior of large lightweight
machine tools that provides the necessary input to the aforementioned
vibration avoidance and reduction methods to properly tackle
machine vibrations is the outlook of the paper.
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: This study aimed to 1) develop pre-service teachers’
leadership skills through camp-based learning, and 2) develop preservice
teachers’ teamwork skills through camp-based learning. An
applied research methodology was used. The target group was
derived from a purposive selection. It involved 32 fourth-year
students in Early Childhood Education Program enrolling a course
entitled Seminar in Early Childhood Education provided during
second semester of academic year 2013. The treatment was camp-based
learning activities which applied a PDCA process including
four stages: 1) plan, 2) do, 3) check, and 4) act. Research instruments
were a learning camp program, a camp-based learning management
plan, a 5-level assessment form for leadership skills and a 5-level
assessment form for assessing teamwork skills. Data were analyzed
using descriptive statistics. Results were: 1) pre-service teachers’
leadership skills yielded the before treatment average score at x= 3.4,
S.D.=0.6 2and the after-treatment average score at x 4.29 , S.D.=0.66
pre-service teachers’ teamwork skills yielded the before-treatment
average score at x=3.31, S.D.=0.60 and the after-treatment average
score at x=4.42, S.D.=0.66 Both differences were statistically
significant at the .05 level. Thus, the pre-service teachers’ leadership
and teamwork skills were significantly improved through the camp-based
learning approach.