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: With drug resistance becoming widespread in
Plasmodium falciparum infections, the development of the alternative
drugs is the desired strategy for prevention and cure of malaria. Three
drug targets were selected to screen promising drug molecules from
the GSK library of 13469 molecules. Using an in silico structure-based
drug designing approach, the differences in binding energies of
the substrate and inhibitor were exploited between target sites of
parasite and human to design a drug molecule against Plasmodium.
The docking studies have shown several promising molecules from
GSK library with more effective binding as compared to the already
known inhibitors for the drug targets. Though stronger interaction has
been shown by several molecules as compared to the reference, few
molecules have shown the potential as drug candidates though in
vitro studies are required to validate the results. In case of
thymidylate synthase-dihydrofolatereductase (TS-DHFR), three
compounds have shown promise for future studies as potential drugs.
Abstract: Polycyclic aromatic hydrocarbons (PAHs) are formed
during the pyrolysis of scrap tyres to produce tyre pyrolytic oil
(TPO). Due to carcinogenic, mutagenic, and toxic properties PAHs
are priority pollutants. Hence it is essential to remove PAHs from
TPO before utilising TPO as a petroleum fuel alternative (to run the
engine). Agricultural wastes have promising future to be utilized as
biosorbent due to their cost effectiveness, abundant availability, high
biosorption capacity and renewability. Various low cost adsorbents
were prepared from natural sources. Uptake of PAHs present in tyre
pyrolytic oil was investigated using various low-cost adsorbents of
natural origin including sawdust (shisham), coconut fiber, neem bark,
chitin, activated charcoal. Adsorption experiments of different PAHs
viz. naphthalene, acenaphthalene, biphenyl and anthracene have been
carried out at ambient temperature (25°C) and at pH 7. It was
observed that for any given PAH, the adsorption capacity increases
with the lignin content. Freundlich constant Kf and 1/n have been
evaluated and it was found that the adsorption isotherms of PAHs
were in agreement with a Freundlich model, while the uptake
capacity of PAHs followed the order: activated charcoal> saw dust
(shisham) > coconut fiber > chitin. The partition coefficients in
acetone-water, and the adsorption constants at equilibrium, could be
linearly correlated with octanol–water partition coefficients. It is
observed that natural adsorbents are good alternative for PAHs
removal. Sawdust of Dalbergia sissoo, a by-product of sawmills was
found to be a promising adsorbent for the removal of PAHs present in
TPO. It is observed that adsorbents studied were comparable to those
of some conventional adsorbents.
Abstract: Standard processes, similar and limited production
lines, the production of high direct costs will be more accurate than
the use of parts of the traditional cost systems in the literature.
However, direct costs, overhead expenses, in turn, decrease the
burden of increasingly sophisticated production facilities, a situation
that led the researchers to look for the cost of traditional systems of
alternative techniques. Variety cost management approaches for
example Total quality management (TQM), just-in-time (JIT),
benchmarking, kaizen costing, targeting cost, life cycle costs (LLC),
activity-based costing (ABC) value engineering have been
introduced. Management and cost applications have changed over the
past decade and will continue to change. Modern cost systems can
provide relevant and accurate cost information. These methods
provide the decisions about customer, product and process
improvement. The aim of study is to describe and explain the
adoption and application of costing systems in SME. This purpose
reports on a survey conducted during 2014 small and medium sized
enterprises (SME) in Ankara. The survey results were evaluated
using SPSS18 package program.
Abstract: The decision-making process is theoretically clearly
defined. Generally, it includes the problem identification and
analysis, data gathering, goals and criteria setting, alternatives
development and optimal alternative choice and its implementation.
In practice however, various modifications of the theoretical
decision-making process can occur. The managers can consider some
of the phases to be too complicated or unfeasible and thus they do not
carry them out and conversely some of the steps can be
overestimated.
The aim of the paper is to reveal and characterize the perception of
the individual phases of decision-making process by the managers.
The research is concerned with managers in the military environment
– commanders. Quantitative survey is focused cross-sectionally in the
individual levels of management of the Ministry of Defence of the
Czech Republic. On the total number of 135 respondents the analysis
focuses on which of the decision-making process phases are
problematic or not carried out in practice and which are again
perceived to be the easiest. Then it is examined the reasons of the
findings.
Abstract: Microbial fuel cells (MFCs) represent a promising
technology for simultaneous bioelectricity generation and wastewater
treatment. Catalysts are significant portions of the cost of microbial
fuel cell cathodes. Many materials have been tested as aqueous
cathodes, but air-cathodes are needed to avoid energy demands for
water aeration. The sluggish oxygen reduction reaction (ORR) rate at
air cathode necessitates efficient electrocatalyst such as carbon
supported platinum catalyst (Pt/C) which is very costly. Manganese
oxide (MnO2) was a representative metal oxide which has been
studied as a promising alternative electrocatalyst for ORR and has
been tested in air-cathode MFCs. However the single MnO2 has poor
electric conductivity and low stability. In the present work, the MnO2
catalyst has been modified by doping Pt nanoparticle. The goal of the
work was to improve the performance of the MFC with minimum Pt
loading. MnO2 and Pt nanoparticles were prepared by hydrothermal
and sol gel methods, respectively. Wet impregnation method was
used to synthesize Pt/MnO2 catalyst. The catalysts were further used
as cathode catalysts in air-cathode cubic MFCs, in which anaerobic
sludge was inoculated as biocatalysts and palm oil mill effluent
(POME) was used as the substrate in the anode chamber. The asprepared
Pt/MnO2 was characterized comprehensively through field
emission scanning electron microscope (FESEM), X-Ray diffraction
(XRD), X-ray photoelectron spectroscopy (XPS), and cyclic
voltammetry (CV) where its surface morphology, crystallinity,
oxidation state and electrochemical activity were examined,
respectively. XPS revealed Mn (IV) oxidation state and Pt (0)
nanoparticle metal, indicating the presence of MnO2 and Pt.
Morphology of Pt/MnO2 observed from FESEM shows that the
doping of Pt did not cause change in needle-like shape of MnO2
which provides large contacting surface area. The electrochemical
active area of the Pt/MnO2 catalysts has been increased from 276 to
617 m2/g with the increase in Pt loading from 0.2 to 0.8 wt%. The
CV results in O2 saturated neutral Na2SO4 solution showed that
MnO2 and Pt/MnO2 catalysts could catalyze ORR with different
catalytic activities. MFC with Pt/MnO2 (0.4 wt% Pt) as air cathode
catalyst generates a maximum power density of 165 mW/m3, which
is higher than that of MFC with MnO2 catalyst (95 mW/m3). The
open circuit voltage (OCV) of the MFC operated with MnO2 cathode
gradually decreased during 14 days of operation, whereas the MFC
with Pt/MnO2 cathode remained almost constant throughout the
operation suggesting the higher stability of the Pt/MnO2 catalyst.
Therefore, Pt/MnO2 with 0.4 wt% Pt successfully demonstrated as an
efficient and low cost electrocatalyst for ORR in air cathode MFC with higher electrochemical activity, stability and hence enhanced
performance.
Abstract: The main aim of this research was to investigate a
prototype bamboo shading device. There were two objectives to this
study: first, to investigate the effects of non-chemical treatments on
bamboo shading devices damaged by powder-post beetles and fungi,
and second to develop a prototype bamboo shading device. This
study of the effects of non-chemical treatments on bamboo shading
devices damage by powder-post beetles in the laboratory showed
that, among seven treatments tested, wood vinegar treatment can
protect powder-post beetles better than the original method by up to
92.91%. It was also found that wood vinegar treatment shows the
best performance in fungi protection and works better than the
original method by up to 40%. A second experiment was carried out
by constructing four bamboo shading devices and installing them on
a building for 28 days. All aspects of shading device were
investigated in terms of their beauty, durability, and ease of
construction and assembly. The final prototype was developed from
the lessons learned from the test results. In conclusion, this study
showed the effectiveness of some natural preservatives against insect
and fungi damage, and it also illustrated the characteristics of a
prototype bamboo shading device that can be constructed by rural
workers within one week.
Abstract: The development of Drugs Delivery System (DDS)
has been widely investigated in the last decades. In this paper, first a
general overview of traditional and modern wound dressing is
presented. This is followed by a review of what scientists have done
in the medical environment, focusing on the possibility to develop a
new alternative for DDS through transdermal pathway, aiming to
treat melanoma skin cancer.
Abstract: This study examines analytically the effect of tsunami loads on reinforced concrete (RC) frame buildings. The impact of tsunami wave loads and waterborne objects are analyzed using a typical substandard full-scale two-story RC frame building tested as part of the EU-funded Ecoleader project. The building was subjected to shake table tests in bare condition, and subsequently strengthened using Carbon Fiber Reinforced Polymers (CFRP) composites and retested. Numerical models of the building in both bare and CFRP-strengthened conditions are calibrated in DRAIN-3DX software to match the test results. To investigate the response of wave loads and impact forces, the numerical models are subjected to nonlinear dynamic analyses using force time-history input records. The analytical results are compared in terms of displacements at the floors and at the “impact point” of a boat. The results show that the roof displacement of the CFRP-strengthened building reduced by 63% when compared to the bare building. The results also indicate that strengthening only the mid-height of the impact column using CFRP is more effective at reducing damage when compared to strengthening other parts of the column. Alternative solutions to mitigate damage due to tsunami loads are suggested.
Abstract: This study evaluated the use of raw or processed
Prosopis juliflora (Meskit) pods as a major ingredient in a formulated
ration to provide an alternative non-conventional concentrate for
livestock feeding in Oman. Dry Meskit pods were reduced to lengths
of 0.5- 1.0 cm to ensure thorough mixing into three diets. Meskit
pods were subjected to two types of treatments; roasting and soaking.
They were roasted at 150оC for 30 minutes using a locally-made
roasting device (40 kg barrel container rotated by electric motor and
heated by flame gas cooker). Chopped pods were soaked in tap water
for 24 hours and dried for 2 days under the sun with frequent turning.
The Meskit-pod-based diets (MPBD) were formulated and pelleted
from 500 g/kg ground Meskit pods, 240 g/kg wheat bran, 200 g/kg
barley grain, 50 g/kg local dried sardines and 10 g/kg of salt. Twenty
four 10 months-old intact Omani male lambs with average body
weight of 27.3 kg (± 0.5 kg) were used in a feeding trial for 84 days.
They were divided (on body weight basis) and allocated to four diet
combination groups. These were: Rhodes grass hay (RGH) plus a
general ruminant concentrate (GRC); RGH plus raw Meskit pods
(RMP) based concentrate; RGH plus roasted Meskit pods (ROMP)
based concentrate; RGH plus soaked Meskit pods (SMP) based
concentrate Daily feed intakes and bi-weekly body weights were
recorded. MPBD had higher contents of crude protein (CP), acid
detergent fibre (ADF) and neutral detergent fibre (NDF) than the
GRC. Animals fed various types of MPBD did not show signs of ill
health. There was a significant effect of feeding ROMP on the
performance of Omani sheep compared to RMP and SMP. The
ROMP fed animals had similar performance to those fed the GRC in
terms of feed intake, body weight gain and feed conversion ratio
(FCR).This study indicated that roasted Meskit pods based diet may
be used instead of the commercial concentrate for feeding Omani
sheep without adverse effects on performance. It offers a cheap
alternative source of protein and energy for feeding Omani sheep.
Also, it might help in solving the spread impact of Meskit trees,
maintain the ecosystem and helping in preserving the local tree
species.
Abstract: Elastomeric dielectric material has recently become a
new alternative for actuator technology. The characteristics of
dielectric elastomers placed between two electrodes to withstand
large strain when electrodes are charged has attracted the attention of
many researcher to study this material for actuator technology. Thus,
in the past few years Danfoss Ventures A/S has established their own
dielectric electro-active polymer (DEAP), which was called
PolyPower.
The main objective of this work was to investigate the dynamic
characteristics for vibration control of a PolyPower actuator folded in
‘pull’ configuration. A range of experiments was carried out on the
folded actuator including passive (without electrical load) and active
(with electrical load) testing. For both categories static and dynamic
testing have been done to determine the behavior of folded DEAP
actuator.
Voltage-Strain experiments show that the DEAP folded actuator is
a non-linear system. It is also shown that the voltage supplied has no
effect on the natural frequency. Finally, varying AC voltage with
different amplitude and frequency shows the parameters that
influence the performance of DEAP folded actuator. As a result, the
actuator performance dominated by the frequency dependence of the
elastic response and was less influenced by dielectric properties.
Abstract: PLA emerged as a promising polymer because of its
property as a compostable, biodegradable thermoplastic made from
renewable sources. PLA can be polymerized from monomers
(Lactide or Lactic acid) obtained by fermentation processes from
renewable sources such as corn starch or sugarcane. For PLA
synthesis, ring opening polymerization (ROP) of Lactide monomer is
one of the preferred methods. In the literature, the technique mainly
developed for ROP of PLA is based on metal/bimetallic catalyst (Sn,
Zn and Al) or other organic catalysts in suitable solvent. However,
the PLA synthesized using such catalysts may contain trace elements
of the catalyst which may cause toxicity. This work estimated the
usefulness and drawbacks of using different catalysts as well as effect
of alternative energies and future aspects for PLA production.
Abstract: Ocimum americanum L (Lamiaceae) is an annual herb
that is native to tropical Africa. The in vitro and in vivo antioxidant
activity of its aqueous extract was carefully investigated by assessing
the DPPH radical scavenging activity, ABTS radical scavenging
activity and hydrogen peroxide radical scavenging activity. The
reducing power, total phenol, total flavonoids and flavonols content
of the extract were also evaluated. The data obtained revealed that the
extract is rich in polyphenolic compounds and scavenged the radicals
in a concentration dependent manner. This was done in comparison
with the standard antioxidants such as BHT and Vitamin C. Also, the
induction of oxidative damage with paracetamol (2000 mg/kg)
resulted in the elevation of lipid peroxides and significant (P < 0.05)
decrease in activities of superoxide dismutase, glutathione
peroxidase, glutathione reductase and catalase in the liver and kidney
of rats. However, the pretreatment of rats with aqueous extract of O.
americanum leaves (200 and 400 mg/kg) and silymarin (100 mg/kg)
caused a significant (P < 0.05) reduction in the values of lipid
peroxides and restored the levels of antioxidant parameters in these
organs. These findings suggest that the leaves of O. americanum have
potent antioxidant properties which may be responsible for its
acclaimed folkloric uses.
Abstract: The tombolo of Giens is located in the town of Hyères
(France). We recall the history of coastal erosion, and prominent
factors affecting the evolution of the western tombolo. We then
discuss the possibility of stabilizing the western tombolo. Our
argumentation relies on a coupled model integrating swells, currents,
water levels and sediment transport. We present the conclusions of
the simulations of various scenarios, including pre-existing
propositions from coastal engineering offices. We conclude that
beach replenishment seems to be necessary but not sufficient for the
stabilization of the beach. Breakwaters reveal effective particularly in
the most exposed northern area. Some solutions fulfill conditions so
as to be elected as satisfactory. We give a comparative analysis of the
efficiency of 14 alternatives for the protection of the tombolo.
Abstract: A Motzkin shift is a mathematical model for constraints
on genetic sequences. In terms of the theory of symbolic dynamics,
the Motzkin shift is nonsofic, and therefore, we cannot use the Perron-
Frobenius theory to calculate its topological entropy. The Motzkin
shift M(M,N) which comes from language theory, is defined to be the
shift system over an alphabet A that consists of N negative symbols,
N positive symbols and M neutral symbols. For an x in the full shift,
x will be in the Motzkin subshift M(M,N) if and only if every finite
block appearing in x has a non-zero reduced form. Therefore, the
constraint for x cannot be bounded in length. K. Inoue has shown that
the entropy of the Motzkin shift M(M,N) is log(M + N + 1). In this
paper, a new direct method of calculating the topological entropy of
the Motzkin shift is given without any measure theoretical discussion.
Abstract: In the present work, the alloy of Bismuth-lead is
prepared on the basis of percentage of molecular weight 9:1, 5:5 and
1:9 ratios and grown by Zone- Refining Technique under a vacuum
atmosphere. The EDAX of these samples are done and the results are
reported. Micro hardness test has been used as an alternative test for
measuring material’s tensile properties. The effect of temperature and
load on the hardness of the grown alloy has been studied. Further the
comparative studies of work hardening coefficients are reported.
Abstract: The adsorption efficiency of fired clayey pellets of 5
and 8 mm diameter size for Cu(II) and Zn(II) ion removal from a
waste printing developer was studied. In order to investigate the
influence of contact time, adsorbent mass and pellet size on the
adsorption efficiency the batch mode was carried out. Faster uptake
of copper ion was obtained with the fired clay pellets of 5 mm
diameter size within 30 minutes. The pellets of 8 mm diameter size
showed the higher equilibrium time (60 to 75 minutes) for copper and
zinc ion. The results pointed out that adsorption efficiency increases
with the increase of adsorbent mass. The maximal efficiency is
different for Cu(II) and Zn(II) ion due to the pellet size. Therefore,
the fired clay pellets of 5 mm diameter size present an effective
adsorbent for Cu(II) ion removal (adsorption efficiency is 63.6%),
whereas the fired clay pellets of 8 mm diameter size are the best
alternative for Zn(II) ion removal (adsorption efficiency is 92.8%)
from a waste printing developer.
Abstract: In this paper we consider the rule reduct generation
problem. Rule Reduct Generation (RG) and Modified Rule
Generation (MRG) algorithms, that are used to solve this problem,
are well-known. Alternative to these algorithms, we develop Pruning
Rule Generation (PRG) algorithm. We compare the PRG algorithm
with RG and MRG.
Abstract: Shortfall of electrical energy in Pakistan is a challenge
adversely affecting its industrial output and social growth. As
elsewhere, Pakistan derives its electrical energy from a number of
conventional sources. The exhaustion of petroleum and conventional
resources, the rising costs coupled with extremely adverse climatic
effects are taking its toll especially on the under-developed countries
like Pakistan. As alternate, renewable energy sources like hydropower,
solar, wind, even bio-energy and a mix of some or all of them
could provide a credible alternative to the conventional energy
resources that would not only be cleaner but sustainable as well. As a
model, solar energy-based power grid for the near future has been
attempted to offset the energy shortfalls as a mix with our existing
sustainable natural energy resources. An assessment of solar energy
potential for electricity generation is being presented for fulfilling the
energy demands with higher level of reliability and sustainability.
This model is based on the premise that solar energy potential of
Pakistan is not only reliable but also sustainable. This research
estimates the present & future approaching renewable energy
resource specially the impact of solar energy based power grid for
mitigating energy shortage in Pakistan.
Abstract: Pipe failure and leakage is a problematic issue and the
traditional solution of replacing the pipes is costly and time
consuming. Rehabilitation by relining materials based on polymer
composites is an alternative solution towards the degradation problem
of the old piping. This paper provides a brief summary of advances in
technology, methods and materials for relining as well as a summary
of the degradation analyses of the two main composite materials used
for relining, rubber filled epoxy and reinforced polyester baltoflake
when they are exposed in deionized water and elevated temperature
up to 80°C for a duration of 2-14 months in the laboratory.