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: 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: 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: This work reports the potential of using Palm Kernel
(PK) ash and shell as a partial substitute for Portland Cement (PC)
and coarse aggregate in the development of mortar and concrete. PK
ash and shell are agro-waste materials from palm oil mills, the
disposal of PK ash and shell is an environmental problem of concern.
The PK ash has pozzolanic properties that enables it as a partial
replacement for cement and also plays an important role in the
strength and durability of concrete, its use in concrete will alleviate
the increasing challenges of scarcity and high cost of cement. In order
to investigate the PC replacement potential of PK ash, three types of
PK ash were produced at varying temperature (350-750C) and they
were used to replace up to 50% PC. The PK shell was used to replace
up to 100% coarse aggregate in order to study its aggregate
replacement potential. The testing programme included material
characterisation, the determination of compressive strength, tensile
splitting strength and chemical durability in aggressive sulfatebearing
exposure conditions. The 90 day compressive results showed
a significant strength gain (up to 26.2 N/mm2). The Portland cement
and conventional coarse aggregate has significantly higher influence
in the strength gain compared to the equivalent PK ash and PK shell.
The chemical durability results demonstrated that after a prolonged
period of exposure, significant strength losses in all the concretes
were observed. This phenomenon is explained, due to lower change
in concrete morphology and inhibition of reaction species and the
final disruption of the aggregate cement paste matrix.
Abstract: The organizations in the knowledge economy era have
recognized the importance of building knowledge assets for
sustainable growth and development. In comparison to other
industries, Information Technology (IT) enterprises, holds an edge in
developing an effective Knowledge Management (KM) programmethanks
to their in-house technological abilities. This paper tries to
study the various knowledge based incentive programmes and its
effect on Knowledge Sharing and Learning in the context of the
Indian IT sector. A conceptual model is developed linking KM
Incentives, Knowledge Sharing and Learning. A questionnaire study
is conducted to collect primary data from the knowledge workers of
the IT organizations located in India. The data was analysed using
Structural Equation Modeling using Partial Least Square method. The
results show a strong influence of knowledge management incentives
on knowledge sharing and an indirect influence on learning.
Abstract: The development of the United Arab Emirates (UAE)
into a regional trade, tourism, finance and logistics hub has
transformed its real estate markets. However, speculative activity and
price volatility remain concerns. UAE residential market values
(MV) are exposed to fluctuations in capital flows and migration
which, in turn, are affected by geopolitical uncertainty, oil price
volatility and global investment market sentiment. Internally, a
complex interplay between administrative boundaries, land tenure,
building quality and evolving location characteristics fragments UAE
residential property markets. In short, the UAE Residential Valuation
System (UAE-RVS) confronts multiple challenges to collect, filter
and analyze relevant information in complex and dynamic spatial and
capital markets. A robust (RVS) can mitigate the risk of unhelpful
volatility, speculative excess or investment mistakes. The research
outlines the institutional, ontological, dynamic and epistemological
issues at play. We highlight the importance of system capabilities,
valuation standard salience and stakeholders trust.
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: With increasingly more mobile health applications
appearing due to the popularity of smartphones, the possibility arises
that these data can be used to improve the medical diagnostic process,
as well as the overall quality of healthcare, while at the same time
lowering costs. However, as of yet there have been no reports of a
successful combination of patient-generated data from smartphones
with data from clinical routine. In this paper we describe how these
two types of data can be combined in a secure way without
modification to hospital information systems, and how they can
together be used in a medical expert system for automatic nutritional
classification and triage.
Abstract: A large amount of data is typically stored in relational
databases (DB). The latter can efficiently handle user queries which
intend to elicit the appropriate information from data sources.
However, direct access and use of this data requires the end users to
have an adequate technical background, while they should also cope
with the internal data structure and values presented. Consequently
the information retrieval is a quite difficult process even for IT or DB
experts, taking into account the limited contributions of relational
databases from the conceptual point of view. Ontologies enable users
to formally describe a domain of knowledge in terms of concepts and
relations among them and hence they can be used for unambiguously
specifying the information captured by the relational database.
However, accessing information residing in a database using
ontologies is feasible, provided that the users are keen on using
semantic web technologies. For enabling users form different
disciplines to retrieve the appropriate data, the design of a Graphical
User Interface is necessary. In this work, we will present an
interactive, ontology-based, semantically enable web tool that can be
used for information retrieval purposes. The tool is totally based on
the ontological representation of underlying database schema while it
provides a user friendly environment through which the users can
graphically form and execute their queries.
Abstract: Every machine plays roles of client and server
simultaneously in a peer-to-peer (P2P) network. Though a P2P
network has many advantages over traditional client-server models
regarding efficiency and fault-tolerance, it also faces additional
security threats. Users/IT administrators should be aware of risks
from malicious code propagation, downloaded content legality, and
P2P software’s vulnerabilities. Security and preventative measures
are a must to protect networks from potential sensitive information
leakage and security breaches. Bit Torrent is a popular and scalable
P2P file distribution mechanism which successfully distributes large
files quickly and efficiently without problems for origin server. Bit
Torrent achieved excellent upload utilization according to
measurement studies, but it also raised many questions as regards
utilization in settings, than those measuring, fairness, and Bit
Torrent’s mechanisms choice. This work proposed a block selection
technique using Fuzzy ACO with optimal rules selected using ACO.
Abstract: In order to study the aerodynamic performance of a
semi-flexible membrane wing, Fluid-Structure Interaction simulations
have been performed. The fluid problem has been modeled using
two different approaches which are the vortex panel method and the
numerical solution of the Navier-Stokes equations. Nonlinear analysis
of the structural problem is performed using the Finite Element
Method. Comparison between the two fluid solvers has been made.
Aerodynamic performance of the wing is discussed regarding its
lift and drag coefficients and they are compared with those of the
equivalent rigid wing.
Abstract: A computational fluid dynamics (CFD) model is
developed for rechargeable non-aqueous electrolyte lithium-air
batteries with a partial opening for oxygen supply to the cathode.
Multi-phase transport phenomena occurred in the battery are
considered, including dissolved lithium ions and oxygen gas in the
liquid electrolyte, solid-phase electron transfer in the porous
functional materials and liquid-phase charge transport in the
electrolyte. These transport processes are coupled with the
electrochemical reactions at the active surfaces, and effects of
discharge reaction-generated solid Li2O2 on the transport properties
and the electrochemical reaction rate are evaluated and implemented
in the model. The predicted results are discussed and analyzed in terms
of the spatial and transient distribution of various parameters, such as
local oxygen concentration, reaction rate, variable solid Li2O2 volume
fraction and porosity, as well as the effective diffusion coefficients. It
is found that the effect of the solid Li2O2 product deposited at the solid
active surfaces is significant on the transport phenomena and the
overall battery performance.
Abstract: Collection of storm water runoff and forcing it into the
groundwater is the need of the hour to sustain the ground water table.
However, the runoff entraps various types of sediments and other
floating objects whose removal are essential to avoid pollution of
ground water and blocking of pores of aquifer. However, it requires
regular cleaning and maintenance due to problem of clogging. To
evaluate the performance of filter system consisting of coarse sand
(CS), gravel (G) and pebble (P) layers, a laboratory experiment was
conducted in a rectangular column. The effect of variable thickness
of CS, G and P layers of the filtration unit of the recharge shaft on the
recharge rate and the sediment concentration of effluent water were
evaluated.
Medium sand (MS) of three particle sizes, viz. 0.150–0.300 mm
(T1), 0.300–0.425 mm (T2) and 0.425–0.600 mm of thickness 25 cm,
30 cm and 35 cm respectively in the top layer of the filter system and
having seven influent sediment concentrations of 250–3,000 mg/l
were used for experimental study. The performance was evaluated in
terms of recharge rates and clogging time. The results indicated that
100 % suspended solids were entrapped in the upper 10 cm layer of
MS, the recharge rates declined sharply for influent concentrations of
more than 1,000 mg/l. All treatments with higher thickness of MS
media indicated recharge rate slightly more than that of all treatment
with lower thickness of MS media respectively. The performance of
storm water infiltration systems was highly dependent on the
formation of a clogging layer at the filter. An empirical relationship
has been derived between recharge rates, inflow sediment load, size
of MS and thickness of MS with using MLR.
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 paper describes an analysis of Yacht Simulator
international trends and also explains about Yacht. The results are
summarized as follows. Attached to the cockpit are sensors that feed
-back information on rudder angle, boat heel angle and mainsheet
tension to the computer. Energy expenditure of the sailor measure
indirectly using expired gas analysis for the measurement of VO2 and
VCO2. At sea course configurations and wind conditions can be preset
to suit any level of sailor from complete beginner to advanced sailor.
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 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: Biofuels production has come forth as a future
technology to combat the problem of depleting fossil fuels. Bio-based
ethanol production from enzymatic lignocellulosic biomass
degradation serves an efficient method and catching the eye of
scientific community. High cost of the enzyme is the major obstacle
in preventing the commercialization of this process. Thus main
objective of the present study was to optimize composition of
medium components for enhancing cellulase production by newly
isolated strain of Bacillus tequilensis. Nineteen factors were taken
into account using statistical Plackett-Burman Design. The significant
variables influencing the cellulose production were further employed
in statistical Response Surface Methodology using Central
Composite Design for maximizing cellulase production. The
optimum medium composition for cellulase production was: peptone
(4.94 g/L), ammonium chloride (4.99 g/L), yeast extract (2.00 g/L),
Tween-20 (0.53 g/L), calcium chloride (0.20 g/L) and cobalt chloride
(0.60 g/L) with pH 7, agitation speed 150 rpm and 72 h incubation at
37oC. Analysis of variance (ANOVA) revealed high coefficient of
determination (R2) of 0.99. Maximum cellulase productivity of 11.5
IU/ml was observed against the model predicted value of 13 IU/ml.
This was found to be optimally active at 60oC and pH 5.5.
Abstract: It is important to take security measures to protect
your computer information, reduce identify theft, and prevent from
malicious cyber-attacks. With cyber-attacks on the continuous rise,
people need to understand and learn ways to prevent from these
attacks. Cyber-attack is an important factor to be considered if one is
to be able to protect oneself from malicious attacks. Without proper
security measures, most computer technology would hinder home
users more than such technologies would help. Knowledge of how
cyber-attacks operate and protective steps that can be taken to reduce
chances of its occurrence are key to increasing these security
measures. The purpose of this paper is to inform home users on the
importance of identifying and taking preventive steps to avoid cyberattacks.
Throughout this paper, many aspects of cyber-attacks will be
discuss: what a cyber-attack is, the affects of cyber-attack for home
users, different types of cyber-attacks, methodology to prevent such
attacks; home users can take to fortify security of their computer.