Abstract: Africa enjoys some of the best solar radiation levels in
the world averaging between 4-6 kWh/m2/day for most of the year
and the global economic and political conditions that tend to make
African countries more dependent on their own energy resources
have caused growing interest in renewable energy based
technologies. However to-date, implementation of modern Energy
Technologies in Africa is still very low especially the use of solar
conversion technologies. This paper presents literature review and
analysis relating to the techno-economic feasibility of solar
photovoltaic power generation in Africa. The literature is basically
classified into the following four main categories. Techno-economic
feasibility of solar photovoltaic power generation, design methods,
performance evaluations of various systems and policy of potential
future of technological development of photovoltaic (PV) in Africa
by exploring the impact of alternative policy instruments and
technology cost reductions on the financial viability of investing solar
photovoltaic in Africa.
Abstract: Skin aging is a slow multifactorial process influenced
by both internal as well as external factors. Ultra-violet radiations
(UV), diet, smoking and personal habits are the most common
environmental factors that affect skin aging. Fat contents and fibrous
proteins as collagen and elastin are core internal structural
components. The direct influence of UV on elastin integrity and
health is central on aging of skin especially by time. The deposition
of abnormal elastic material is a major marker in a photo-aged skin.
Searching for compounds that may protect against cutaneous photodamage
is exceedingly valued. Retinoids and alpha hydroxy acids
have been endorsed by some researchers as possible candidates for
protecting and or repairing the effect of UV damaged skin. For
consolidating a better system of anti- and protective effects of such
anti-aging agents, we evaluated the combinatory effects of various
dosages of lactic acid and retinol on the dermal fibroblast’s elastin
levels exposed to UV. The UV exposed cells showed significant
reduction in the elastin levels. A combination of drugs with a higher
concentration of lactic acid (30 -35 mM) and a lower concentration of
retinol (10-15mg/mL) showed to work better in maintaining elastin
concentration in UV exposed cells. We assume this preservation
could be the result of increased tropo-elastin gene expression
stimulated by retinol whereas lactic acid probably repaired the UV
irradiated damage by enhancing the amount and integrity of the
elastin fibers.
Abstract: In this paper, effects of using Alumina-water
nanofluid on the rate of heat transfer have been investigated
numerically. Physical model is a square enclosure with insulated top
and bottom horizontal walls, while the vertical walls are kept at
different constant temperatures. Two appropriate models are used to
evaluate the viscosity and thermal conductivity of nanofluid. The
governing stream-vorticity equations are solved using a second order
central finite difference scheme, coupled to the conservation of mass
and energy. The study has been carried out for the Richardson
number 0.1 to 10 and the solid volume fraction 0 to 0.04. Results are
presented by isotherms lines, average Nusselt number and normalized
Nusselt number in different range of φ and Ri for forced, combined
and natural convection dominated regime. It is found that higher heat
transfer rate is predicted when the effects of nanoparticle is taken into
account.
Abstract: Humans are social mammals, of the primate order.
Our biology, our behaviour and our pathologies are unique to us. In
our desire to understand, reduce solitary confinement one source of
information is the many reports of social isolation of other social
mammals, especially primates. A behavioural study was conducted in
the department of pharmacology at Indira Gandhi Medical College,
Shimla in Himachalpradesh province in India using white albino
mice. Different behavioural parameters were observed by using open
field, tail suspension, tests for aggressive behaviour and social
interactions and the effect of isolation was studied. The results were
evaluated and the standard statistics were applied. The said study was
done to establish facts that isolation itself impairs social behaviour
and can lead to alcohol dependence as well as related drug
dependence.
Abstract: A well designed and executed Production Planning
and Control (PPC) system is one of the key levers for superior
performance in the current manufacturing set-up. Hence, measuring
the PPC system performance has become a necessity for long term
success. The present study examined PPC related issues which
impact the production capacity and productivity of leather companies
with special focus on Kombolcha Tannery Share Company (KTSC),
Ethiopia. Physical observation, interview, and questionnaire were
used to generate necessary information from the respondents and
reach valid conclusions. Company annual reports were referred and
analyzed to triangulate primary data. Consequently, the study
revealed that KTSC runs below its capacity due to its inefficient PPC
system being in use for which the root causes were identified. The
study thereby conceptualizes a PPC system improvement framework
comprising three pillars viz., management culture, internal capability
and performance measurement together with key considerations in
each case. The study findings enable the company to recognize the
importance of efficient PPC system as a source of competitive
advantage. It also aid managers in evaluating various PPC execution
schemes to enhance productivity.
Abstract: Numerical studies were conducted using Lattice
Boltzmann Method (LBM) to study the natural convection in a square
cavity in the presence of roughness. An algorithm based on a single
relaxation time Bhatnagar-Gross-Krook (BGK) model of Lattice
Boltzmann Method (LBM) was developed. Roughness was
introduced on both the hot and cold walls in the form of sinusoidal
roughness elements. The study was conducted for a Newtonian fluid
of Prandtl number (Pr) 1.0. The range of Ra number was explored
from 10^3 to 10^6 in a laminar region. Thermal and hydrodynamic
behavior of fluid was analyzed using a differentially heated square
cavity with roughness elements present on both the hot and cold wall.
Neumann boundary conditions were introduced on horizontal walls
with vertical walls as isothermal. The roughness elements were at the
same boundary condition as corresponding walls. Computational
algorithm was validated against previous benchmark studies
performed with different numerical methods, and a good agreement
was found to exist. Results indicate that the maximum reduction in
the average heat transfer was 16.66 percent at Ra number 10^5.
Abstract: Everyday life is and will be influenced depending on
the developments that society undergoes throughout the history.
Particularly, countries undergoing transition from one system to
another sustain the greatest impact in trying to embrace the modern
system. Kosovo society had the fortune to experience a change,
which began in late 1999 to continue up to date. One of the
'developments' of the time with the evolution in Kosovo society was
the transition from the traditional education system into the modern
one. This transformation began immediately after the war, to
continue even today. It was started by internationals, which governed
and administered Kosovo society, including education. There was a
great 'evolution', because almost the entire system was 'changed'.
Among other things, for the first time it was enabled the opening of
private schools from the lowest level up to the colleges and
universities. This paper will address: how much was ready the society
to embrace such a 'cultural' change in education, respectively, how
much were prepared teachers for such changes; as it was actually
thought to be a modern education system, how much was it according
to international standards; what are the results and current situation in
Kosovo education.
Abstract: Poly vinyl acetate (PVA)-based titania (TiO2)–carbon
nanotube composite nanofibers (PVA-TCCNs) with various
PVA-to-solvent ratios and PVA-based TiO2 composite nanofibers
(PVA-TN) were synthesized using an electrospinning process,
followed by thermal treatment. The photocatalytic activities of these
nanofibers in the degradation of airborne monocyclic aromatics under
visible-light irradiation were examined. This study focuses on the
application of these photocatalysts to the degradation of the target
compounds at sub-part-per-million indoor air concentrations. The
characteristics of the photocatalysts were examined using scanning
electron microscopy, X-ray diffraction, ultraviolet-visible
spectroscopy, and Fourier-transform infrared spectroscopy. For all the
target compounds, the PVA-TCCNs showed photocatalytic
degradation efficiencies superior to those of the reference PVA-TN.
Specifically, the average photocatalytic degradation efficiencies for
benzene, toluene, ethyl benzene, and o-xylene (BTEX) obtained using
the PVA-TCCNs with a PVA-to-solvent ratio of 0.3 (PVA-TCCN-0.3)
were 11%, 59%, 89%, and 92%, respectively, whereas those observed
using PVA-TNs were 5%, 9%, 28%, and 32%, respectively.
PVA-TCCN-0.3 displayed the highest photocatalytic degradation
efficiency for BTEX, suggesting the presence of an optimal
PVA-to-solvent ratio for the synthesis of PVA-TCCNs. The average
photocatalytic efficiencies for BTEX decreased from 11% to 4%, 59%
to 18%, 89% to 37%, and 92% to 53%, respectively, when the flow
rate was increased from 1.0 to 4.0 L min1. In addition, the average
photocatalytic efficiencies for BTEX increased 11% to ~0%, 59% to
3%, 89% to 7%, and 92% to 13%, respectively, when the input
concentration increased from 0.1 to 1.0 ppm. The prepared
PVA-TCCNs were effective for the purification of airborne aromatics
at indoor concentration levels, particularly when the operating
conditions were optimized.
Abstract: Electroencephalogram (EEG) is a noninvasive
technique that registers signals originating from the firing of neurons
in the brain. The Emotiv EEG Neuroheadset is a consumer product
comprised of 14 EEG channels and was used to record the reactions
of the neurons within the brain to two forms of stimuli in 10
participants. These stimuli consisted of auditory and visual formats
that provided directions of ‘right’ or ‘left.’ Participants were
instructed to raise their right or left arm in accordance with the
instruction given. A scenario in OpenViBE was generated to both
stimulate the participants while recording their data. In OpenViBE,
the Graz Motor BCI Stimulator algorithm was configured to govern
the duration and number of visual stimuli. Utilizing EEGLAB under
the cross platform MATLAB®, the electrodes most stimulated during
the study were defined. Data outputs from EEGLAB were analyzed
using IBM SPSS Statistics® Version 20. This aided in determining
the electrodes to use in the development of a brain-machine interface
(BMI) using real-time EEG signals from the Emotiv EEG
Neuroheadset. Signal processing and feature extraction were
accomplished via the Simulink® signal processing toolbox. An
Arduino™ Duemilanove microcontroller was used to link the Emotiv
EEG Neuroheadset and the right and left Mecha TE™ Hands.
Abstract: The article discusses the legal framework of the
government’s environmental function and analyzes the role of the
national policy in protection of wetlands. The problem is of interest
for it deals with the most important branch of economy – utilization
of Kazakhstan’s natural resources, protection of health and
environmental wellbeing of the population. Development of a longterm
environmental program addressing the protection of wetlands
represents the final stage of the government’s environmental policy,
and is a relatively new function for the public administration system.
It appeared due to the environmental measures that require immediate
decisions to be taken. It is an integral part of the effort in the field of
management of state-owned natural resource, as well as of the
measures aimed at efficient management of natural resources to avoid
their early depletion or contamination.
Abstract: Carbon Deposits are often occurred inside the
industrial coke oven during coking process. Accumulation of carbon
deposits may cause a big issue, which seriously influences the coking
operation. The carbon is burning off by injecting fresh air through
pipes into coke oven which is an efficient way practically operated in
industries. The burning off carbon deposition in coke oven performed
by Computational Fluid Dynamics (CFD) method has provided an
evaluation of the feasibility study. A three dimensional, transient,
turbulent reacting flow simulation has performed with three different
injecting air flow rate and another kind of injecting configuration. The
result shows that injection higher air flow rate would effectively
reduce the carbon deposits. In the meantime, the opened charging
holes would suck extra oxygen from atmosphere to participate in
reactions. In term of coke oven operating limits, the wall temperatures
are monitored to prevent over-heating of the adiabatic walls during
burn-off process.
Abstract: Pedagogy has always been open to other disciplines
that reflect about the educational process (philosophy, sociology,
psychology, anthropology, technology, etc.). Its interdisciplinary
openness puts education, as the subject of pedagogy within a broader
context of the community, enabling the knowledge of other
disciplines to contribute to a better understanding of the fundamental
pedagogical notion of education. The purpose of pedagogy as a
science serves humans, strives towards humans, must be for humans,
and this is its ultimate goal. Humans are essentially dependent on
education, which is also considered as a category of humans’ being,
because through education an entire world develops in humans.
Anthropological assumptions of humans as "deficient beings" see the
solution in education, but they also indicate a wealth of shortcomings,
because they provide an opportunity for enrichment and formation of
culture, living and the self. In that context, this paper illustrates the
determination of pedagogy through an anthropological conception of
humans and the phenomenon of education. It presents a review of
anthropological ideas about education, by providing an analysis of
relevant literature dealing with the anthropological notion of humans,
which provides fruitful conditions for a pedagogical reconsideration
of education.
Abstract: Presently, it is necessary to ensure the sustainable
development of passenger and freight transport. Increasing
performance of road freight has had a negative impact to environment
and society. It is therefore necessary to increase the competitiveness
of intermodal transport, which is more environmentally friendly. The
study describes the effectiveness of logistical centers realization for
companies and society and research how the partial internalization of
external costs reflected in the efficient use of these centers and
increase the competitiveness of intermodal transport to road freight.
In our research, we use the method of comparative analysis and
market research to describe the advantages of logistic centers for their
users as well as for society as a whole. Method normal costing is used
for calculation infrastructure and total costs, method of conversion
costing for determine the external costs. We modelled total society
costs for road freight transport and inter modal transport chain (we
assumed that most of the traffic is carried by rail) with different
loading schemes for condition in the Slovak Republic. Our research
has shown that higher utilization of inter modal transport chain do
good not only for society, but for companies providing freight
services too. Increase in use of inter modal transport chain can bring
many benefits to society that do not bring direct immediate financial
return. They often bring the multiplier effects, such as greater use of
environmentally friendly transport mode and reduce the total society
costs.
Abstract: The characteristics of temperature distribution and
electric field in a natural rubber glove (NRG) using microwave
energy during microwave heating process are investigated
numerically and experimentally. A three-dimensional model of NRG
and microwave oven are considered in this work. The influences of
position, heating time and rotation angle of NRG on temperature
distribution and electric field are presented in details. The coupled
equations of electromagnetic wave propagation and heat transfer are
solved using the finite element method (FEM). The numerical model
is validated with an experimental study at a frequency of 2.45 GHz.
The results show that the numerical results closely match the
experimental results. Furthermore, it is found that the temperature
distribution and electric field increases with increasing heating time.
The hot spot zone appears in NRG at the tip of middle finger while
the maximum temperature occurs in case of rotation angle of NRG =
60 degree. This investigation provides the essential aspects for a
fundamental understanding of heat transport of NRG using
microwave energy in industry.
Abstract: Co metal supported on SiO2 and Al2O3 catalysts with
a metal loading varied from 30 of 70 wt.% were evaluated for
decomposition of methane to COx free hydrogen and carbon
nanomaterials. The catalytic runs were carried out from 550-800oC
under atmospheric pressure using fixed bed vertical flow reactor. The
fresh and spent catalysts were characterized by BET surface area
analyzer, XRD, SEM, TEM and TG analysis. The data showed that
50% Co/Al2O3 catalyst exhibited remarkable higher activity at 800oC
with respect to H2 production compared to rest of the catalysts.
However, the catalytic activity and durability was greatly declined at
higher temperature. The main reason for the catalytic inhibition of Co
containing SiO2 catalysts is the higher reduction temperature of
Co2SiO4. TEM images illustrate that the carbon materials with
various morphologies, carbon nanofibers (CNFs), helical-shaped
CNFs and branched CNFs depending on the catalyst composition and
reaction temperature were obtained.
Abstract: The objective of this study was to evaluate the
physical and chemical characteristics of Serra da Estrela cheese and
compare these results with those of the sensory analysis. For the
study were taken six samples of Serra da Estrela cheese produced
with 6 different ecotypes of thistle in a dairy situated in Penalva do
Castelo. The chemical properties evaluated were moisture content,
protein, fat, ash, chloride and pH; the physical properties studied
were color and texture; and finally a sensory evaluation was
undertaken. The results showed moisture varying in the range 40-
48%, protein in the range 15-20%, fat between 41-45%, ash between
3.9-5.0% and chlorides varying from 1.2 to 3.0%. The pH varied
from 4.8 to 5.4. The textural properties revealed that the crust
hardness is relatively low (maximum 7.3 N), although greater than
flesh firmness (maximum 1.7 N), and also that these cheeses are in
fact soft paste type, with measurable stickiness and intense
adhesiveness. The color analysis showed that the crust is relatively
light (L* over 50), and with a predominant yellow coloration (b*
around 20 or over) although with a slight greenish tone (a* negative).
The results of the sensory analysis did not show great variability for
most of the attributes measured, although some differences were
found in attributes such as crust thickness, crust uniformity, and
creamy flesh.
Abstract: Flours of wheat, chestnut, acorn and lupin were
evaluated in relation to phenolic compounds, antioxidant activity, and
oxalate content. At the chemical level the results show some
variability between samples by type of flour, and the sample of
chestnut flour presented the higher value of oxalate (0.00348
mg/100g) when compared to the other samples in the study.
Considering the content of phenolic compounds, the sample that
stood out was the acorn flour, having a high value of 0.812 g
AGE/100 g. All the samples presented intermediate content of
antioxidant activity and the sample that showed a slightly higher
value was the wheat flour with a value of 0.746 mM TRE/g sample.
Abstract: Epidermal Growth Factor (EGF, Mw=6,045) has been
reported to have high efficiency of wound repair and anti-wrinkle
effect. However, the half-life of EGF in the body is too short to exert
the biological activity effectively when applied in free form. Growth
Factors can be stabilized by immobilization with carbohydrates from
thermal and proteolytic degradation. Low molecular weight chitosan
(LMCS) and its derivate prepared by hydrogen peroxide has high
solubility. LM6A6DC was successfully prepared as a reactive
carbohydrate for the stabilization of EGF by the reactions of LMCS
with alkalization, tosylation, azidation and reduction. The structure of
LM6A6DC was confirmed by FT-IR, 1H NMR and elementary
analysis. For enhancing the stability of free EGF, EGF was attached
with LM6A6DC by using water-soluble carbodiimide.
EGF-LM6A6DC conjugates did not show any cytotoxicity on the
Normal Human Dermal Fibroblast (NHDF) 3T3 proliferation at least
under 100 μg/ml. In the result, it was considered that LM6A6DC is
suitable to immobilize of growth factor.
Abstract: In this study, we compare the profiles of transitory
hybrid entrepreneurs and persistent hybrid entrepreneurs to determine
how they differ. Hybrid entrepreneurs (HEs) represent a significant
share of entrepreneurial activity yet little is known about them. We
define HEs as individuals who are active as entrepreneurs but do no
support themselves primarily by their enterprise. Persistent HEs
(PHEs) are not planning to transition to fulltime entrepreneurship
whereas transitory HEs (THEs) consider it probable. Our results
show that THEs and PHEs are quite similar in background. THEs are
more interested in increasing their turnover than PHEs, as expected,
but also emphasize self-fulfillment as a motive for entrepreneurship
more than PHEs. The clearest differences between THEs and PHEs
are found in their views on how well their immediate circle supports
full-time entrepreneurship, and their views of their own
entrepreneurial abilities and the market potential of their firm. Our
results support earlier arguments that hybrids should be considered
separately in research on entrepreneurial entry and self-employment.
Abstract: Surface modification and functionalization has been
an important tool for scientists in order to open new frontiers in
nanoscience and nanotechnology. Desired surface characteristics for
the intended applications can be achieved with surface
functionalization.
In this work, the effect of water soluble ligands on the adsorption
capabilities of silver nanoparticles onto AC which was synthesized
from German beech wood was investigated. Sodium borohydride
(NaBH4) and polyvinyl alcohol (PVA) were used as the ligands.
Silver nanoparticles with different surface coatings have average
sizes range from 10 to 13 nm. They were synthesized in aqueous
media by reducing Ag (I) ion in the presence of ligands. These
particles displayed adsorption tendencies towards AC when they
were mixed together and shaken in distilled water.
Silver nanoparticles (NaBH4-AgNPs) reduced and stabilized by
NaBH4 adsorbed onto AC with a homogenous dispersion of
aggregates with sizes in the range of 100-400 nm. Beside, silver
nanoparticles, which were prepared in the presence of both NaBH4
and PVA (NaBH4/PVA-Ag NPs), demonstrated that NaBH4/PVA-Ag
NPs adsorbed and dispersed homogenously but, they aggregated with
larger sizes on the AC surface (range from 300 to 600 nm). In
addition, desorption resistance of Ag nanoparticles were investigated
in distilled water. According to the results AgNPs were not desorbed
on the AC surface in distilled water.