Abstract: Sustainability and eco-friendly requirement of
engineering materials are sort for in recent times, thus giving rise to
the development of bio-composites. However, the natural fibres to
matrix interface interactions remain a key issue in getting the desired
mechanical properties from such composites. Treatment of natural
fibres is essential in improving matrix to filler adhesion, hence
improving its mechanical properties. In this study, investigations
were carried out to determine the effect of sodium hydroxide
treatment on the tensile, flexural, impact and hardness properties of
crushed and uncrushed Luffa cylindrica fibre reinforced recycled low
density polyethylene composites. The LC (Luffa cylindrica) fibres
were treated with 0%, 2%, 4%, 6%, 8% and 10% wt. sodium
hydroxide (NaOH) concentrations for a period of 24 hours under
room temperature conditions. A formulation ratio of 80/20 g (matrix
to reinforcement) was maintained for all developed samples. Analysis
of the results showed that the uncrushed luffa fibre samples gave
better mechanical properties compared with the crushed luffa fibre
samples. The uncrushed luffa fibre composites had a maximum
tensile and flexural strength of 7.65 MPa and 17.08 Mpa respectively
corresponding to a young modulus and flexural modulus of 21.08
MPa and 232.22 MPa for the 8% and 4% wt. NaOH concentration
respectively. Results obtained in the research showed that NaOH
treatment with the 8% NaOH concentration improved the mechanical
properties of the LC fibre reinforced composites when compared with
other NaOH treatment concentration values.
Abstract: The planning of geological survey works is an
iterative process which involves planner, geologist, civil engineer and
other stakeholders, who perform different roles and have different
points of view. Traditionally, the team used paper maps or CAD
drawings to present the proposal which is not an efficient way to
present and share idea on the site investigation proposal such as
sitting of borehole location or seismic survey lines. This paper
focuses on how a GIS approach can be utilised to develop a webbased
system to support decision making process in the planning of
geological survey works and also to plan site activities carried out by
Singapore Geological Office (SGO). The authors design a framework
of building an interactive web-based GIS system, and develop a
prototype, which enables the users to obtain rapidly existing
geological information and also to plan interactively borehole
locations and seismic survey lines via a web browser. This prototype
system is used daily by SGO and has shown to be effective in
increasing efficiency and productivity as the time taken in the
planning of geological survey works is shortened. The prototype
system has been developed using the ESRI ArcGIS API 3.7 for Flex
which is based on the ArcGIS 10.2.1 platform.
Abstract: The research studies the behaviors based on
sufficiency economy philosophy at individual and community
levelsas well as the satisfaction of the urban community leaders by
collecting data with purposive sampling technique. For in-depth
interviews with 26 urban community leaders, the result shows that
the urban community leaders have good knowledge and
understanding about sufficiency economy philosophy. Especially in
terms of money spending, they must consider the need for living and
be economical. The activities in the community or society should not
take advantage of the others as well as colleagues. At present, most of
the urban community leaders live in sufficient way. They often spend
time with public service, but many families are dealing with debt.
Many communities have some political conflict and high family
allowances because of living in the urban communities with rapid
social and economic changes. However, there are many communities
that leaders have applied their wisdom in development for their
people by gathering and grouping the professionals to form activities
such as making chilli sauce, textile organization, making artificial
flowers to worship the sanctity. The most prominent group is the foot
massage business in Wat Pracha Rabue Tham. This professional
group is supported continuously by the government. One of the
factors in terms of satisfaction used for evaluating community leaders
is the customary administration in brotherly, interdependent way
rather than using the absolute power or controlling power, but using
the roles of leader to perform the activities with their people intently,
determinedly and having public mind for people.
Abstract: Non-linear FEM calculations are indispensable when
important technical information like operating performance of a
rubber component is desired. For example rubber bumpers built into
air-spring structures may undergo large deformations under load,
which in itself shows non-linear behavior. The changing contact
range between the parts and the incompressibility of the rubber
increases this non-linear behavior further. The material
characterization of an elastomeric component is also a demanding
engineering task.
The shape optimization problem of rubber parts led to the study of
FEM based calculation processes. This type of problems was posed
and investigated by several authors. In this paper the time demand of
certain calculation methods are studied and the possibilities of time
reduction is presented.
Abstract: Composite material based on Fe3Si micro-particles
and Mn-Zn nano-ferrite was prepared using powder metallurgy
technology. The sol-gel followed by autocombustion process was
used for synthesis of Mn0.8Zn0.2Fe2O4 ferrite. 3 wt.% of mechanically
milled ferrite was mixed with Fe3Si powder alloy. Mixed micro-nano
powder system was homogenized by the Resonant Acoustic Mixing
using ResodynLabRAM Mixer. This non-invasive homogenization
technique was used to preserve spherical morphology of Fe3Si
powder particles. Uniaxial cold pressing in the closed die at pressure
600 MPa was applied to obtain a compact sample. Microwave
sintering of green compact was realized at 800°C, 20 minutes, in air.
Density of the powders and composite was measured by
Hepycnometry. Impulse excitation method was used to measure
elastic properties of sintered composite. Mechanical properties were
evaluated by measurement of transverse rupture strength (TRS) and
Vickers hardness (HV). Resistivity was measured by 4 point probe
method. Ferrite phase distribution in volume of the composite was
documented by metallographic analysis.
It has been found that nano-ferrite particle distributed among
micro- particles of Fe3Si powder alloy led to high relative density
(~93%) and suitable mechanical properties (TRS >100 MPa, HV
~1GPa, E-modulus ~140 GPa) of the composite. High electric
resistivity (R~6.7 ohm.cm) of prepared composite indicate their
potential application as soft magnetic material at medium and high
frequencies.
Abstract: Since, it is essential to provide homeless people by the
earthquake with safe, habitable accommodation repairing medium
and slight levels of damage at the connection parts should be
undertaken. In order to prove that a repaired connection was
sufficiently strong, a precast beam to column post tensioned
connection was tested in three phases. In phase one, the middle level
damage was observed at 6% drift at these connections. As a result of
the extra loads applied, little damage was observed. In the last phase,
the four connections tested in the first phase were repaired using
epoxy resin and then retested. The results from the tests on the
repaired precast and the undamaged specimens showed that the
repaired specimens were sufficiently strong, thus proving that repair
to damaged precast beam to column post tensioned connections can
be undertaken.
Abstract: Various personality profile tests are used to identify
personality strengths and limits in individuals, helping both
individuals and managers to optimize work and team effort in
organizations. One such test, the Hartman’s personality profile,
emphasizes four driving "core motives" influenced or affected by
both strengths and limitations classified into four colors: Red -
motivated by power; Blue - discipline and loyalty; White - peace; and
Yellow – fun loving. Two shortcomings of Hartman’s personality test
are noted; 1) only one selection for every item / situation allowed and
2) selection of an item / option even if not applicable. A test taker
may be as much nurturing as he is opinionated but since
“opinionated” seems less attractive the individual would likely select
nurturing, causing a misidentification in personality strengths and
limits. Since few individuals have a “strong” personality, it is
difficult to assess their true personality strengths and limits allowing
only one choice or requiring unwanted choices, undermining the
potential of the test. We modified Hartman’s personality profile
allowing test takers to make either multiple choices for any item /
situation or leave them blank if applicable. Sixty-eight participants
(38 males and 30 females), 17 - 49 years old, from countries in Asia,
Europe, N. America, CIS, Africa, Latin America, and Oceania were
included. 58 participants (85.3%) reported the modified test, allowing
multiple / no choices better identified their personality strengths and
limits, while 10 participants (14.7%) expressed the original (one
choice version) was sufficient. The overall results show that our
modified test enhanced the identification and balance of core
personalities’ strengths and limits, aiding test takers, managers and
organizations to better assess individual characteristics, particularly
useful in making task-related, teamwork, and management decisions.
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: Newly synthesized Polypropylene-g-Polyethylene
glycol polymer was first time used for a compartment-less enzymatic
fuel cell. Working electrodes based on Polypropylene-g-Polyethylene
glycol were operated as unmediated and mediated system (with
ferrocene and gold/cobalt oxide nanoparticles). Glucose oxidase and
bilirubin oxidase was selected as anodic and cathodic enzyme,
respectively. Glucose was used as fuel in a single-compartment and
membrane-less cell. Maximum power density was obtained as 0.65
nW cm-2, 65 nW cm-2 and 23500 nW cm-2 from the unmediated,
ferrocene and gold/cobalt oxide modified polymeric film,
respectively. Power density was calculated to be ~16000 nW cm-2 for
undiluted wastewater sample with gold/cobalt oxide nanoparticles
including system.
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: A numerical study of natural convection heat transfer
in water filled cavity has been examined in 3-Dfor single phase liquid
cooling system by using an array of parallel plate fins mounted to one
wall of a cavity. The heat generated by a heat source represents a
computer CPU with dimensions of 37.5∗37.5mm mounted on
substrate. A cold plate is used as a heat sink installed on the opposite
vertical end of the enclosure. The air flow inside the computer case is
created by an exhaust fan. A turbulent air flow is assumed and k-ε
model is applied. The fins are installed on the substrate to enhance
the heat transfer. The applied power energy range used is between 15
- 40W. In order to determine the thermal behaviour of the cooling
system, the effect of the heat input and the number of the parallel
plate fins are investigated. The results illustrate that as the fin number
increases the maximum heat source temperature decreases. However,
when the fin number increases to critical value the temperature start
to increase due to the fins are too closely spaced and that cause the
obstruction of water flow. The introduction of parallel plate fins
reduces the maximum heat source temperature by 10% compared to
the case without fins. The cooling system maintains the maximum
chip temperature at 64.68°C when the heat input was at 40W that is
much lower than the recommended computer chips limit temperature
of no more than 85°C and hence the performance of the CPU is
enhanced.
Abstract: Environmental impact assessment techniques have
been developed as a result of the worldwide efforts to reduce the
environmental impact of global warming. By using the quantification
method in the construction industry, it is now possible to manage the
greenhouse gas is to systematically evaluate the impact on the
environment over the entire construction process. In particular, the
proportion of greenhouse gas emissions at the production stage of
construction material occupied is high, and efforts are needed in
particular in the construction field.
In this research, intended for concrete products for the construction
materials, by using the LCA method, we compared the results of
environmental impact assessment and carbon emissions of developing
products that have been applied low-carbon technologies compared to
existing products. As a results, by introducing a raw material of
industrial waste, showed carbon reduction. Through a comparison of
the carbon emission reduction effect of low carbon technologies, it is
intended to provide academic data for the evaluation of greenhouse
gases in the construction sector and the development of low carbon
technologies of the future.
Abstract: This paper presents the simulation results of the
effects of sampling frequency on the total harmonic distortion (THD)
of three-phase inverters using the space vector pulse width
modulation (SVPWM) and space vector control (SVC) algorithms.
The relationship between the variables was studied using curve fitting
techniques, and it has been shown that, for 50 Hz inverters, there is
an exponential relation between the sampling frequency and THD up
to around 8500 Hz, beyond which the performance of the model
becomes irregular, and there is an negative exponential relation
between the sampling frequency and the marginal improvement to
the THD. It has also been found that the performance of SVPWM is
better than that of SVC with the same sampling frequency in most
frequency range, including the range where the performance of the
former is irregular.
Abstract: The air transport impact on environment is more than
ever a limitative obstacle to the aeronautical industry continuous
growth. Over the last decades, considerable effort has been carried
out in order to obtain quieter aircraft solutions, whether by changing
the original design or investigating more silent maneuvers. The
noise propagated by rotating surfaces is one of the most important
sources of annoyance, being present in most aerial vehicles. Bearing
this is mind, CEIIA developed a new computational chain for
noise prediction with in-house software tools to obtain solutions in
relatively short time without using excessive computer resources. This
work is based on the new acoustic tool, which aims to predict the
rotor noise generated during steady and maneuvering flight, making
use of the flexibility of the C language and the advantages of GPU
programming in terms of velocity. The acoustic tool is based in the
Formulation 1A of Farassat, capable of predicting two important
types of noise: the loading and thickness noise. The present work
describes the most important features of the acoustic tool, presenting
its most relevant results and framework analyses for helicopters and
UAV quadrotors.
Abstract: This paper presents an efficient fusion algorithm for
iris images to generate stable feature for recognition in unconstrained
environment. Recently, iris recognition systems are focused on real
scenarios in our daily life without the subject’s cooperation. Under
large variation in the environment, the objective of this paper is to
combine information from multiple images of the same iris. The
result of image fusion is a new image which is more stable for further
iris recognition than each original noise iris image. A wavelet-based
approach for multi-resolution image fusion is applied in the fusion
process. The detection of the iris image is based on Adaboost
algorithm and then local binary pattern (LBP) histogram is then
applied to texture classification with the weighting scheme.
Experiment showed that the generated features from the proposed
fusion algorithm can improve the performance for verification system
through iris recognition.
Abstract: This paper examines how “Zakat” provides fair
income redistribution and aids the struggle against poverty. Providing
fair income redistribution and combating poverty constitutes some of
the fundamental tasks performed by countries all over the world.
Each country seeks a solution for these problems according to their
political, economic and administrative styles through applying
various economic and financial policies. The same situation can be
handled via “zakat” association in Islam. Nowadays, we observe
different versions of “zakat” in developed countries. Applications
such as negative income tax denote merely a different form of
“zakat” that is being applied almost in the same way but under
changed names. However, the minimum values to donate under zakat
(e.g. 85 gr. gold and 40 animals) get altered and various amounts are
put into practice. It might be named as negative income tax instead of
zakat, nonetheless, these applications are based on the Holy Koran
and the hadith released 1400 years ago. Besides, considering the
savage and slavery in the world at those times, we might easily
recognize the true value of the zakat being applied for the first time
then in the Islamic system. Through zakat, governments are able to
transfer incomes to the poor as a means of enabling them achieve the
minimum standard of living required. With regards to who benefits
from the Zakat, an objective and fair criteria was used to determine
who benefits from the zakat contrary to the notion that it was based
on peoples’ own choices. Since the zakat is obligatory, the transfers
do not get forwarded directly but via the government and get
distributed, which requires vast governmental organizations. Through
the application of Zakat, reduced levels of poverty can be achieved
and also ensure the fair income redistribution.
Abstract: The paper deals with the diagnostics of steel roof
structure of the winter sports halls built in 1970 year. The necessity
of the diagnostics has been given by the requirement to the evaluation
design of this structure, which has been caused by the new situation
in the field of the loadings given by the validity of the European
Standards in the Czech Republic from 2010 year. Due to these
changes in the normative rules, in practice existing structures are
gradually subjected to the evaluation design and depending on its
results to the strengthening or reconstruction, respectively. Steel roof
is composed of plane truss main girders, purlins and bracings and the
roof structure is supported by two arch main girders with the span of
L = 84 m. The in situ diagnostics of the roof structure was oriented to
the following parts: (i) determination and evaluation of the actual
material properties of used steel and (ii) verification of the actual
dimensions of the structural members. For the solution the nondestructive
methods have been used for in situ measurement. For the
indicative determination of steel strengths the modified method based
on the determination of Rockwell’s hardness has been used. For the
verification of the member’s dimensions (thickness of hollow
sections) the ultrasound method has been used. This paper presents
the results obtained using these testing methods and their evaluation,
from the viewpoint of the usage for the subsequent static assessment
and design evaluation of the existing structure. For the comparison,
the examples of the similar evaluations realized for steel structures of
the stadiums in Olomouc and Jihlava cities are briefly illustrated, too.
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: In this investigation, we have evaluated the effects of
arsenic trioxide on hepatic function in pregnant and lactating Swiss
albino mice and their suckling pups. Experiments were carried out on
female mice given 175 ppm As2O3 in their drinking water from the
14th day of pregnancy until day 14 after delivery. Our results showed
a significant decrease in plasma levels of total protein and albumin,
cholesterol and triglyceride in As2O3 treated mice and their pups. The
hyperbilirubinemia and the increased plasma total alkaline
phosphatase activity suggested the presence of cholestasis.
Transaminase activities as well as lactate deshydrogenase activity in
plasma, known as biomarkers of hepatocellular injury, were elevated
indicating hepatic cells’ damage after treatment with As2O3.
Exposure to arsenic led to an increase of liver thiobarbituric acid
reactive substances level along with a concomitant decrease in the
activities of superoxide dismutase, catalase and glutathione
peroxidase and in glutathione.
Abstract: An investigation into Cahn-Hilliard equation was
carried out through numerical simulation to identify a possible phase
separation for one and two dimensional domains. It was observed that
this equation can reproduce important mass fluxes necessary for
phase separation within the miscibility gap and for coalescence of
particles.