Abstract: An investigation has been presented to analyze the
effect of internal heat source on the onset of Hadley-Prats flow in
a horizontal fluid saturated porous medium. We examine a better
understanding of the combined influence of the heat source and mass
flow effect by using linear stability analysis. The resultant eigenvalue
problem is solved by using shooting and Runga-Kutta methods for
evaluate critical thermal Rayleigh number with respect to various
flow governing parameters. It is identified that the flow is switch from
stabilizing to destabilizing as the horizontal thermal Rayleigh number
is enhanced. The heat source and mass flow increases resulting a
stronger destabilizing effect.
Abstract: The global demand for long-tailed macaques for
medical experimentation has continued to increase. Fulfillment of
Indonesian export demands has been mostly from natural habitats,
based on a harvesting quota. This quota has been determined
according to the total catch for a given year, and not based on
consideration of any demographic parameters or physical
environmental factors with regard to the animal; hence threatening
the sustainability of the various populations. It is therefore necessary
to formulate a method for calculating a sustainable harvesting quota,
based on population parameters in natural habitats. Considering the
possibility of variations in habitat characteristics and population
parameters, a time series observation of demographic and
physical/biotic parameters, in various habitats, was performed on 13
groups of long-tailed macaques, distributed throughout the West
Java, Lampung and Yogyakarta areas of Indonesia. These provinces
were selected for comparison of the influence of human/tourism
activities. Data on population parameters that was collected included
data on life expectancy according to age class, numbers of
individuals by sex and age class, and ‘ratio of infants to reproductive
females’. The estimation of population growth was based on a
population dynamic growth model: the Leslie matrix. The harvesting
quota was calculated as being the difference between the actual
population size and the MVP (minimum viable population) for each
sex and age class. Observation indicated that there were variations within group size
(24–106 individuals), gender (sex) ratio (1:1 to 1:1.3), life expectancy
value (0.30 to 0.93), and ‘ratio of infants to reproductive females’
(0.23 to 1.56). Results of subsequent calculations showed that
sustainable harvesting quotas for each studied group of long-tailed
macaques, ranged from 29 to 110 individuals. An estimation model
of the MVP for each age class was formulated as Log Y = 0.315 +
0.884 Log Ni (number of individual on ith age class). This study also
found that life expectancy for the juvenile age class was affected by
the humidity under tree stands, and dietary plants’ density at sapling,
pole and tree stages (equation: Y=2.296 – 1.535 RH + 0.002 Kpcg –
0.002 Ktg – 0.001 Kphn, R2 = 89.6% with a significance value of
0.001). By contrast, for the sub-adult-adult age class, life expectancy
was significantly affected by slope (equation: Y=0.377 = 0.012 Kml,
R2 = 50.4%, with significance level of 0.007). The infant-toreproductive-
female ratio was affected by humidity under tree stands,
and dietary plant density at sapling and pole stages (equation: Y = -
1.432 + 2.172 RH – 0.004 Kpcg + 0.003 Ktg, R2 = 82.0% with
significance level of 0.001). This research confirmed the importance
of population parameters in determining the minimum viable
population, and that MVP varied according to habitat characteristics
(especially food availability). It would be difficult therefore, to
formulate a general mathematical equation model for determining a
harvesting quota for the species as a whole.
Abstract: Sewer deposits have been identified as a major cause
of dysfunctions in combined sewer systems regarding sewer
management, which induces different negative consequents resulting
in poor hydraulic conveyance, environmental damages as well as
worker’s health. In order to overcome the problematics of
sedimentation, flushing has been considered as the most operative
and cost-effective way to minimize the sediments impacts and
prevent such challenges. Flushing, by prompting turbulent wave
effects, can modify the bed form depending on the hydraulic
properties and geometrical characteristics of the conduit. So far, the
dynamics of the bed-load during high-flow events in combined sewer
systems as a complex environment is not well understood, mostly due
to lack of measuring devices capable to work in the “hostile” in
combined sewer system correctly. In this regards, a one-episode
flushing issue from an opening gate valve with weir function was
carried out in a trunk sewer in Paris to understand its cleansing
efficiency on the sediments (thickness: 0-30 cm). During more than
1h of flushing within 5 m distance in downstream of this flushing
device, a maximum flowrate and a maximum level of water have
been recorded at 5 m in downstream of the gate as 4.1 m3/s and 2.1
m respectively. This paper is aimed to evaluate the efficiency of this
type of gate for around 1.1 km (from the point -50 m to +1050 m in
downstream from the gate) by (i) determining bed grain-size
distribution and sediments evolution through the sewer channel, as
well as their organic matter content, and (ii) identifying sections that
exhibit more changes in their texture after the flush. For the first one,
two series of sampling were taken from the sewer length and then
analyzed in laboratory, one before flushing and second after, at same
points among the sewer channel. Hence, a non-intrusive sampling
instrument has undertaken to extract the sediments smaller than the
fine gravels. The comparison between sediments texture after the
flush operation and the initial state, revealed the most modified zones
by the flush effect, regarding the sewer invert slope and hydraulic
parameters in the zone up to 400 m from the gate. At this distance,
despite the increase of sediment grain-size rages, D50 (median grainsize)
varies between 0.6 mm and 1.1 mm compared to 0.8 mm and 10
mm before and after flushing, respectively. Overall, regarding the
sewer channel invert slope, results indicate that grains smaller than
sands (< 2 mm) are more transported to downstream along about 400
m from the gate: in average 69% before against 38% after the flush
with more dispersion of grain-sizes distributions. Furthermore, high
effect of the channel bed irregularities on the bed material evolution
has been observed after the flush.
Abstract: This study aims to investigate the mixing behaviors of
deionized (DI) water and carboxymethyl cellulose (CMC) solutions in
C-shaped serpentine micromixers over a wide range of flow
conditions. The flow of CMC solutions exhibits shear-thinning
behaviors. Numerical simulations are performed to investigate the
effects of the mean flow speed, fluid properties and geometry
parameters on flow and mixing in the micromixers with the serpentine
channel of the same overall channel length. From the results, we can
find the following trends. When convection dominates fluid mixing,
the curvature-induced vortices enhance fluid mixing effectively. The
mixing efficiency of a micromixer consisting of semicircular C-shaped
repeating units with a smaller centerline radius is better than that of a
micromixer consisting of major segment repeating units with a larger
centerline radius. The viscosity of DI water is less than the overall
average apparent viscosity of CMC solutions, and so the effect of
curvature-induced vortices on fluid mixing in DI water is larger than
that in CMC solutions for the cases with the same mean flow speed.
Abstract: Commercial banks in Nigeria adopted many strategies
to attract fresh deposits including the use of high deposit rate.
However, pricing of banking services moved in favor of the banks at
the expense of customers, resulting in their seeking other investment
alternatives rather than saving their money in the bank. Both deposit
and lending rates were greatly influenced by the Central Bank of
Nigeria (CBN) decision on interest rate. Therefore, commercial bank
effort to attract deposits via manipulation of her rates was greatly
limited, otherwise the banks will be giving out more than it earned.
The study aimed at examining the relationship between interest rate
and fixed fund deposit of commercial banks, how policy-controlled
interest rate affected commercial bank’s fixed fund deposit The
researcher employed ordinary least square technique, using, multiple
linear regression, unrestricted vector auto-regression, correlation
matrix test, granger causality and impulse response graph in the
analysis. Commercial bank’s interest rates affected commercial
bank’s fixed fund deposit significantly while policy-controlled
interest rate did not significantly transmit through the commercial
bank’s interest rates to affect fixed fund deposit. While commercial
banks seek creative ways to expand their fixed fund deposit, policy
authorities in Nigeria should better coordinate interest rate fluctuation
and induce competition in the entire financial sector.
Abstract: One of the most critical decision points in the design of a
face recognition system is the choice of an appropriate face representation.
Effective feature descriptors are expected to convey sufficient, invariant
and non-redundant facial information. In this work we propose a set of
Hahn moments as a new approach for feature description. Hahn moments
have been widely used in image analysis due to their invariance, nonredundancy
and the ability to extract features either globally and locally.
To assess the applicability of Hahn moments to Face Recognition we
conduct two experiments on the Olivetti Research Laboratory (ORL)
database and University of Notre-Dame (UND) X1 biometric collection.
Fusion of the global features along with the features from local facial
regions are used as an input for the conventional k-NN classifier. The
method reaches an accuracy of 93% of correctly recognized subjects for
the ORL database and 94% for the UND database.
Abstract: The disposal and the treatment of sewage sludge is an
expensive and environmentally complex problem. In this work, a
lipopeptide biosurfactant extracted from corn steep liquor was used
as ecofriendly and cost-competitive alternative for the mobilization
and bioremediation of fluorene in sewage sludge. Results have
demonstrated that this biosurfactant has the capability to mobilize
fluorene to the aqueous phase, reducing the amount of fluorene in the
sewage sludge from 484.4 mg/Kg up to 413.7 mg/Kg and 196.0
mg/Kg after 1 and 27 days respectively. Furthermore, once the
fluorene was extracted the lipopeptide biosurfactant contained in the
aqueous phase allowed the biodegradation, up to 40.5% of the initial
concentration of this polycyclic aromatic hydrocarbon.
Abstract: This study integrates a larger research empirical
project that examines second language (SL) learners’ profiles and
valid procedures to perform complete and diagnostic assessment in
schools. 102 learners of Portuguese as a SL aged 7 and 17 years
speakers of distinct home languages were assessed in several
linguistic tasks. In this article, we focused on writing performance in
the specific task of narrative essay composition. The written outputs
were measured using the score in six components adapted from an
English SL assessment context (Alberta Education): linguistic
vocabulary, grammar, syntax, strategy, socio-linguistic, and
discourse. The writing processes and strategies in Portuguese
language used by different immigrant students were analysed to
determine features and diversity of deficits on authentic texts
performed by SL writers. Differentiated performance was based on
the diversity of the following variables: grades, previous schooling,
home language, instruction in first language, and exposure to
Portuguese as Second Language. Indo-Aryan languages speakers
showed low writing scores compared to their peers and the type of
language and respective cognitive mapping (such as Mandarin and
Arabic) was the predictor, not linguistic distance. Home language
instruction should also be prominently considered in further research
to understand specificities of cognitive academic profile in a
Romance languages learning context. Additionally, this study also
examined the teachers’ representations that will be here addressed to
understand educational implications of second language teaching in
psychological distress of different minorities in schools of specific
host countries.
Abstract: This paper deals with nonlinear vibration analysis
using finite element method for frame structures consisting of elastic
and viscoelastic damping layers supported by multiple nonlinear
concentrated springs with hysteresis damping. The frame is supported
by four nonlinear concentrated springs near the four corners. The
restoring forces of the springs have cubic non-linearity and linear
component of the nonlinear springs has complex quantity to represent
linear hysteresis damping. The damping layer of the frame structures
has complex modulus of elasticity. Further, the discretized equations in
physical coordinate are transformed into the nonlinear ordinary
coupled differential equations using normal coordinate corresponding
to linear natural modes. Comparing shares of strain energy of the
elastic frame, the damping layer and the springs, we evaluate the
influences of the damping couplings on the linear and nonlinear impact
responses. We also investigate influences of damping changed by
stiffness of the elastic frame on the nonlinear coupling in the damped
impact responses.
Abstract: A large amount of software products offer a wide
range and number of features. This is called featuritis or creeping
featurism and tends to rise with each release of the product. Feautiris
often adds unnecessary complexity to software, leading to longer
learning curves and overall confusing the users and degrading their
experience. We take a look to a new design approach tendency that
has been coming up, the so-called “What You Get is What You
Need” concept that argues that products should be very focused,
simple and with minimalistic interfaces in order to help users conduct
their tasks in distraction-free ambiences. This isn’t as simple to
implement as it might sound and the developers need to cut down
features. Our contribution illustrates and evaluates this design method
through a novel distraction-free diagramming tool named Delineato
Pro for Mac OS X in which the user is confronted with an empty
canvas when launching the software and where tools only show up
when really needed.
Abstract: This research paper presents guiding on how to design
social media into higher education courses. The research
methodology used a survey approach. The research instrument was a
questionnaire about guiding on how to design social media into
higher education courses. Thirty-one lecturers completed the
questionnaire. The data were scored by frequency and percentage.
The research results were the lecturers’ opinions concerning the
designing social media into higher education courses as follows: 1)
Lecturers deem that the most suitable learning theory is Collaborative
Learning. 2) Lecturers consider that the most important learning and
innovation Skill in the 21st century is communication and
collaboration skills. 3) Lecturers think that the most suitable
evaluation technique is authentic assessment. 4) Lecturers consider
that the most appropriate portion used as blended learning should be
70% in the classroom setting and 30% online.
Abstract: In this paper, we report the development of the device
for diagnostics of cardiovascular system state and associated
automated workstation for large-scale medical measurement data
collection and analysis. It was shown that optimal design for the
monitoring device is wristband as it represents engineering trade-off
between accuracy and usability. Monitoring device is based on the
infrared reflective photoplethysmographic sensor, which allows
collecting multiple physiological parameters, such as heart rate and
pulsing wave characteristics. Developed device uses BLE interface
for medical and supplementary data transmission to the coupled
mobile phone, which processes it and send it to the doctor's
automated workstation. Results of this experimental model
approbation confirmed the applicability of the proposed approach.
Abstract: In order to obtain efficient pollutants removal in
small-scale wastewater treatment plants, uniform water flow has to be
achieved. The experimental setup, designed for treating high-load
wastewater (leachate), consists of two aerobic biological reactors and
a lamellar settler. Both biological tanks were aerated by using three
different types of aeration systems - perforated pipes, membrane air
diffusers and tube ceramic diffusers. The possibility of homogenizing
the water mass with each of the air diffusion systems was evaluated
comparatively. The oxygen concentration was determined by optical
sensors with data logging. The experimental data was analyzed
comparatively for all three different air dispersion systems aiming to
identify the oxygen concentration variation during different
operational conditions. The Oxygenation Capacity was calculated for
each of the three systems and used as performance and selection
parameter. The global mass transfer coefficients were also evaluated
as important tools in designing the aeration system. Even though
using the tubular porous diffusers leads to higher oxygen
concentration compared to the perforated pipe system (which
provides medium-sized bubbles in the aqueous solution), it doesn’t
achieve the threshold limit of 80% oxygen saturation in less than 30
minutes. The study has shown that the optimal solution for the
studied configuration was the radial air diffusers which ensure an
oxygen saturation of 80% in 20 minutes. An increment of the values
was identified when the air flow was increased.
Abstract: In this article, we deal with a variant of the classical
course timetabling problem that has a practical application in many
areas of education. In particular, in this paper we are interested in
high schools remedial courses. The purpose of such courses is to
provide under-prepared students with the skills necessary to succeed
in their studies. In particular, a student might be under prepared in
an entire course, or only in a part of it. The limited availability
of funds, as well as the limited amount of time and teachers at
disposal, often requires schools to choose which courses and/or which
teaching units to activate. Thus, schools need to model the training
offer and the related timetabling, with the goal of ensuring the
highest possible teaching quality, by meeting the above-mentioned
financial, time and resources constraints. Moreover, there are some
prerequisites between the teaching units that must be satisfied. We
first present a Mixed-Integer Programming (MIP) model to solve
this problem to optimality. However, the presence of many peculiar
constraints contributes inevitably in increasing the complexity of
the mathematical model. Thus, solving it through a general-purpose
solver may be performed for small instances only, while solving
real-life-sized instances of such model requires specific techniques
or heuristic approaches. For this purpose, we also propose a heuristic
approach, in which we make use of a fast constructive procedure
to obtain a feasible solution. To assess our exact and heuristic
approaches we perform extensive computational results on both
real-life instances (obtained from a high school in Lecce, Italy) and
randomly generated instances. Our tests show that the MIP model is
never solved to optimality, with an average optimality gap of 57%.
On the other hand, the heuristic algorithm is much faster (in about the
50% of the considered instances it converges in approximately half of
the time limit) and in many cases allows achieving an improvement
on the objective function value obtained by the MIP model. Such an
improvement ranges between 18% and 66%.
Abstract: Low Temperature Matrix Isolation - Electron
Paramagnetic Resonance (LTMI-EPR) Spectroscopy was utilized to
identify the species of iron oxide nanoparticles generated during the
oxidative pyrolysis of 1-methylnaphthalene (1-MN). The otherwise
gas-phase reactions of 1--MN were impacted by a polypropylenimine
tetra-hexacontaamine dendrimer complexed with iron (III) nitrate
nonahydrate diluted in air under atmospheric conditions. The EPR
fine structure of Fe (III)2O3 nanoparticles clusters, characterized by gfactors
of 2.00, 2.28, 3.76 and 4.37 were detected on a cold finger
maintained at 77 K after accumulation over a multitude of
experiments. Additionally, a high valence Fe (IV) paramagnetic
intermediate and superoxide anion-radicals, O2•- adsorbed on
nanoparticle surfaces in the form of Fe (IV) --- O2•- were detected
from the quenching area of Zone 1 in the gas-phase.
Abstract: The possibility of application the dietary fibers in
production of crackers was observed in this work, as well as their
influence on rheological and textural properties on the dough for
crackers and influence on sensory properties of obtained crackers.
Three different dietary fibers, oat, potato and pea fibers, replaced
10% of wheat flour. Long fermentation process and baking test
method were used for crackers production. The changes of dough for
crackers were observed by rheological methods of determination the
viscoelastic dough properties and by textural measurements. Sensory
quality of obtained crackers was described using quantity descriptive
method (QDA) by trained members of descriptive panel. Additional
analysis of crackers surface was performed by videometer. Based on
rheological determination, viscoelastic properties of dough for
crackers were reduced by application of dietary fibers. Manipulation
of dough with 10% of potato fiber was disabled, thus the recipe
modification included increase in water content at 35%. Dough
compliance to constant stress for samples with dietary fibers
decreased, due to more rigid and stiffer dough consistency compared
to control sample. Also, hardness of dough for these samples
increased and dough extensibility decreased. Sensory properties of
final products, crackers, were reduced compared to control sample.
Application of dietary fibers affected mostly hardness, structure and
crispness of the crackers. Observed crackers were low marked for
flavor and taste, due to influence of fibers specific aroma. The sample
with 10% of potato fibers and increased water content was the most
adaptable to applied stresses and to production process. Also this
sample was close to control sample without dietary fibers by
evaluation of sensory properties and by results of videometer method.
Abstract: Main objective of this paper is to establish a link
between inertial forces of the bearings used in construction of wind
power plant and its behavior. Using bearings with lower inertial
forces has the immediate effect of decreasing inertia rotor system,
with significant results in increased energy efficiency, due to
decreased friction forces between rollers and raceways. The F.E.M.
analysis shows the appearance of uniform contact stress at the ends of
the rollers, demonstrated the necessity of production of low mass
bearings. Favorable results are expected in the economic field, by
reducing material consumption and by increasing the durability of
bearings. Using low mass bearings with hollow rollers instead of
solid rollers has an impact on working temperature, on vibrations and
noise which decrease. Implementation of types of hollow rollers of
cylindrical tubular type, instead of expensive rollers with logarithmic
profile, will bring significant inertial forces decrease with large
benefits in behavior of wind power plant.
Abstract: This paper is concerned with the single-item
continuous review inventory system in which demand is stochastic
and discrete. The budget consumed for purchasing the ordered items
is not restricted but it incurs extra cost when exceeding specific
value. The unit purchasing price depends on the quantity ordered
under the all-units discounts cost structure. In many actual systems,
the budget as a resource which is occupied by the purchased items is
limited and the system is able to confront the resource shortage by
charging more costs. Thus, considering the resource shortage costs as
a part of system costs, especially when the amount of resource
occupied by the purchased item is influenced by quantity discounts,
is well motivated by practical concerns. In this paper, an optimization
problem is formulated for finding the optimal (r, Q) policy, when the
system is influenced by the budget limitation and a discount pricing
simultaneously. Properties of the cost function are investigated and
then an algorithm based on a one-dimensional search procedure is
proposed for finding an optimal (r, Q) policy which minimizes the
expected system costs.
Abstract: Constructed Wetland (CW) is a reasonable method to
treat wastewater. Current study was carried out to co-treat landfill
leachate and domestic wastewater using a CW system. Typha
domingensis was transplanted to CW, which encloses two substrate
layers of adsorbents named ZELIAC and zeolite. Response surface
methodology and central composite design were employed to
evaluate experimental data. Contact time (h) and leachate-towastewater
mixing ratio (%; v/v) were selected as independent
factors. Phenols and manganese removal were selected as dependent
responses. At optimum contact time (48.7 h) and leachate-towastewater
mixing ratio (20.0%), removal efficiencies of phenols and
manganese removal efficiencies were 90.5%, and 89.4%,
respectively.
Abstract: In order to help the expert to validate association rules
extracted from data, some quality measures are proposed in the
literature. We distinguish two categories: objective and subjective
measures. The first one depends on a fixed threshold and on data
quality from which the rules are extracted. The second one consists
on providing to the expert some tools in the objective to explore and
visualize rules during the evaluation step. However, the number of
extracted rules to validate remains high. Thus, the manually mining
rules task is very hard. To solve this problem, we propose, in this
paper, a semi-automatic method to assist the expert during the
association rule's validation. Our method uses rule-based
classification as follow: (i) We transform association rules into
classification rules (classifiers), (ii) We use the generated classifiers
for data classification. (iii) We visualize association rules with their
quality classification to give an idea to the expert and to assist him
during validation process.