Abstract: This study was conducted to investigate the effect of
the antioxidant activity of germinated African Yam Bean (AYB) on
oxidative stress markers in alloxan induced diabetic rat. Rats were
randomized into three groups; control, diabetic and germinated AYB
– treated diabetic rats. The Total phenol and flavonoid content and
DPPH radical scavenging activity before and after germination were
investigated. The glucose level, lipid peroxidation and reduced
glutathione of the animals were also determined using standard
technique for four weeks. Germination increased the total phenol,
flavonoid and antioxidant activity of AYB extract by 19.14%,
32.28% and 57.25% respectively. The diabetic rats placed on
germinated AYB diet had a significant decrease in the blood glucose
and lipid peroxidation with a corresponding increase in glutathione
(p
Abstract: Since columns are the most important elements of the
structures, failure of one column in a critical location can cause a
progressive collapse. In this respect, the repair and strengthening of
columns is a very important subject to reduce the building failure and
to keep the columns capacity. Twenty columns with different
parameters is tested and analysis. Eleven typical confined reinforced
concrete (RC) columns with different types of techniques are
assessment. And also, four confined concrete columns with plastic
tube (PVC) are tested with and with four paralleling tested of
unconfined plain concrete. The techniques of confined RC columns
are mortar strengthening, Steel rings strengthening, FRP
strengthening. Moreover, the technique of confined plain concrete
(PC) column is used PVC tubes. The columns are tested under
uniaxial compressive loads studied the effect of confinement on the
structural behavior of circular RC columns. Test results for each
column are presented in the form of crack patterns, stress-strain
curves. Test results show that confining of the RC columns using
different techniques of strengthening results significant improvement
of the general behavior of the columns and can used in construction.
And also, tested confined PC columns with PVC tubes results shown
that the confined PC with PVC tubes can be used in economical
building. The theoretical model for predicted column capacity is
founded with experimental factor depends on the confined techniques
used and the strain reduction.
Abstract: A compact UWB planar antenna fed with a
microstrip-line is proposed. The new design consist of a rectangular
patch with symmetric l-shaped slots and fed by 50 Ω microstrip
transmission line and a reduced ground-plane which have a periodic
slots with an overall size of 47 mm x 20 mm. It is intended to be used
in wireless applications that cover the ultra-wideband (UWB)
frequency band. A wider impedance bandwidth of around 116.5%
(1.875 – 7.115 GHz) with stable radiation pattern is achieved. The
proposed antenna has excellent characteristics, low profile and costeffective
compared to existing UWB antennas. The UWB antenna is
designed and analyzed using CST Microwave Studio in transient
mode to verify antenna parameters improvements.
Abstract: This study carried out comparative seismic
performance of reinforced concrete frames infilled by masonry walls
with different heights. Partial and fully infilled reinforced concrete
frames were modeled for the research objectives and the analysis
model for a bare reinforced concrete frame was also established for
comparison. Non–linear static analyses for the studied frames were
performed to investigate their structural behavior under extreme
seismic loads and to find out their collapse mechanism. It was
observed from analysis results that the strengths of the partial infilled
reinforced concrete frames are increased and their ductilities are
reduced, as infilled masonry walls are higher. Especially, reinforced
concrete frames with higher partial infilled masonry walls would
experience shear failures. Non–linear dynamic analyses using 10
earthquake records show that the bare and fully infilled reinforced
concrete frame present stable collapse mechanism while the reinforced
concrete frames with partially infilled masonry walls collapse in more
brittle manner due to short-column effects.
Abstract: Waste silicon carbide (waste SiC) filled high-density
polyethylene (HDPE) with and without surface modifiers were
studied. Two types of surface modifiers namely; high-density
polyethylene-grafted-maleic anhydride (HDPE-g-MA) and 3-aminopropyltriethoxysilane have been used in this study. The
composites were produced using a two roll mill, extruder and shaped
in a hydraulic compression molding machine. The mechanical
properties of polymer composites such as flexural strength and
modulus, impact strength, tensile strength, stiffness and hardness
were investigated over a range of compositions. It was found that,
flexural strength and modulus, tensile modulus and hardness
increased, whereas impact strength and tensile strength decreased
with the increasing in filler contents, compared to the neat HDPE. At
similar filler content, the effect of both surface modifiers increased
flexural modulus, impact strength, tensile strength and stiffness but
reduced the flexural strength. Morphological investigation using
SEM revealed that the improvement in mechanical properties was
due to enhancement of the interfacial adhesion between waste SiC
and HDPE.
Abstract: In this paper, the effect of grades 32.4 and 42.5
Portland-limestone cements generally used for concrete production in
Nigeria on concrete compressive strength is investigated.
Investigation revealed that the compressive strength of concrete
produced with Portland-limestone cement grade 42.5 is generally
higher than that produced with cement grade 32.5. The percentage
difference between the compressive strengths of the concrete cubes
produced with Portland-limestone cement grades 42.5 and 32.5 is
inversely proportional to the richness of the concrete with the highest
and the least percentage difference associated with the 1:2:4 and
1:1:2 mix ratios respectively. It is recommended that cement grade
42.5 be preferred for construction in Nigeria as this will lead to the
construction of stronger concrete structures, which will reduce the
incidence of failure of building and other concrete structures at no
additional cost since the cost of both cement grades are the same.
Abstract: The use OF adhesive anchors for wooden constructions is an efficient technology to connect and design timber members in new timber structures and to rehabilitate the damaged structural members of historical buildings. Due to the lack of standard regulation in this specific area of structural design, designers’ choices are still supported by test analysis that enables knowledge, and the prediction, of the structural behaviour of glued in rod joints. The paper outlines an experimental research activity aimed at identifying the tensile resistance capacity of several new adhesive joint prototypes made of epoxy resin, steel bar and timber, Oak and Douglas Fir species. The development of new adhesive connectors has been carried out by using epoxy to glue stainless steel bars into pre-drilled holes, characterised by smooth and rough internal surfaces, in timber samples. The realization of a threaded contact surface using a specific drill bit has led to an improved bond between wood and epoxy. The applied changes have also reduced the cost of the joints’ production. The paper presents the results of this parametric analysis and a Finite Element analysis that enables identification and study of the internal stress distribution in the proposed adhesive anchors.
Abstract: The well been of human beings on construction site is
very important, many man power had been lost through accidents
which kills or make workers physically unfit to carry out construction
activities, these in turn have multiple effects on the whole economy.
Thus it is necessary to put all safety items and regulations in place
before construction activities can commence. This study was carried
out in Ondo state of Nigeria to known and analyse the state of health
and safety of construction workers in the state. The study was done
using first hand observation method, 50 construction project sites
were visited in 10 major towns of Ondo state, questionnaires were
distributed and the results were analysed. The result show that
construction workers are being exposed to a lot of construction site
hazards due to lack of inadequate safety programmes and nonprovision
of appropriate safety materials for workers on site. From the
data gotten for each site visited and the statistical analysis, it can be
concluded that occurrence of accident on construction sites depends
significantly on the available safety facilities on the sites. The result of
the regression statistics show that the level of significant of the
dependence of occurrence of accident on the availability of safety
items on site is 0.0362 which is less than 0.05 maximum significant
level required. Therefore a vital way of sustaining our building
strategy is by given a detail attention to provision of adequate health
and safety items on construction sites which will reduce the
occurrence of accident, loss of man power and death of skilled
workers among others.
Abstract: The industrial process adds to engineering wood
products features absent in solid wood, with homogeneous structure
and reduced defects, improved physical and mechanical properties,
bio-deterioration, resistance and better dimensional stability,
improving quality and increasing the reliability of structures wood.
These features combined with using fast-growing trees, make them
environmentally ecological products, ensuring a strong consumer
market. The wood I-joists are manufactured by the industrial profiles
bonding flange and web, an important aspect of the production of
wooden I-beams is the adhesive joint that bonds the web to the
flange. Adhesives can effectively transfer and distribute stresses,
thereby increasing the strength and stiffness of the composite. The
objective of this study is to evaluate different resins in a shear strain
specimens with the aim of analyzing the most efficient resin and
possibility of using national products, reducing the manufacturing
cost. First was conducted a literature review, where established the
geometry and materials generally used, then established and analyzed
8 national resins and produced six specimens for each.
Abstract: In this research the effects of adding silica and
alumina nanoparticles on flow ability and compressive strength of
cementitious composites based on Portland cement were investigated.
In the first stage, the rheological behavior of different samples
containing nanosilica, nanoalumina and polypropylene, polyvinyl
alcohol and polyethylene fibers were evaluated. With increasing of
nanoparticles in fresh samples, the slump flow diameter reduced.
Fibers reduced the flow ability of the samples and viscosity
increased. With increasing of the micro silica particles to cement
ratio from 2/1 to 2/2, the slump flow diameter increased. By adding
silica and alumina nanoparticles up to 3% and 2% respectively, the
compressive strength increased and after decreased. Samples
containing silica nanoparticles and fibers had the highest compressive
strength.
Abstract: An analysis is carried out to investigate the effect of
magnetic field and heat source on the steady boundary layer flow and
heat transfer of a Casson nanofluid over a vertical cylinder stretching
exponentially along its radial direction. Using a similarity
transformation, the governing mathematical equations, with the
boundary conditions are reduced to a system of coupled, non –linear
ordinary differential equations. The resulting system is solved
numerically by the fourth order Runge – Kutta scheme with shooting
technique. The influence of various physical parameters such as
Reynolds number, Prandtl number, magnetic field, Brownian motion
parameter, thermophoresis parameter, Lewis number and the natural
convection parameter are presented graphically and discussed for non
– dimensional velocity, temperature and nanoparticle volume
fraction. Numerical data for the skin – friction coefficient, local
Nusselt number and the local Sherwood number have been tabulated
for various parametric conditions. It is found that the local Nusselt
number is a decreasing function of Brownian motion parameter Nb
and the thermophoresis parameter Nt.
Abstract: The design and plantwide control of an integrated
plant where the endothermic 1,4-butanediol dehydrogenation and the
exothermic furfural hydrogenation is simultaneously performed in a
single reactor is studied. The reactions can be carried out in an
adiabatic reactor using small hydrogen excess and with reduced
parameter sensitivity. The plant is robust and flexible enough to
allow different production rates of γ-butyrolactone and 2-methyl
furan, keeping high product purities. Rigorous steady state and
dynamic simulations performed in AspenPlus and AspenDynamics to
support the conclusions.
Abstract: Malaysia is rich with historic buildings, particularly in
Penang and Malacca states. Restoration activities are increasingly
important as these states are recognized under UNESCO World
Heritage Sites. Restoration activities help to maintain the uniqueness
and value of a heritage building. However, increasing in restoration
activities has resulted in large quantities of waste. To cope with this
problem, the 3R concept (reduce, reuse and recycle) is introduced.
The 3R concept is one of the waste management hierarchies. This
concept is still yet to apply in the building restoration industry
compared to the construction industry. Therefore, this study aims to
promote the 3R concept in the heritage building restoration industry.
This study aims to examine the importance of 3R concept and to
identify challenges in applying the 3R concept in the heritage
building restoration industry. This study focused on contractors and
consultants who are involved in heritage restoration projects in
Penang. Literature review and interviews helps to reach the research
objective. Data that obtained is analyzed by using content analysis.
For the research, application of 3R concept is important to conserve
natural resources and reduce pollution problems. However, limited
space to organise waste is the obstruction during the implementation
of this concept. In conclusion, the 3R concept plays an important role
in promoting environmental conservation and helping in reducing the
construction waste.
Abstract: Managing and improving efficiency in the current
highly competitive global automotive industry demands that those
companies adopt leaner and more flexible systems. During the past
20 years the domestic automotive industry in North America has been
focusing on establishing new management strategies in order to meet
market demands. The lean management process also known as
Toyota Manufacturing Process (TPS) or lean manufacturing
encompasses tools and techniques that were established in order to
provide the best quality product with the fastest lead time at the
lowest cost. The following paper presents a study that focused on
improving labor efficiency at one of the Big Three (Ford, GM,
Chrysler LLC) domestic automotive facility in North America. The
objective of the study was to utilize several lean management tools in
order to optimize the efficiency and utilization levels at the “Pre-
Marriage” chassis area in a truck manufacturing and assembly
facility. Utilizing three different lean tools (i.e. Standardization of
work, 7 Wastes, and 5S) this research was able to improve efficiency
by 51%, utilization by 246%, and reduce operations by 14%. The
return on investment calculated based on the improvements made
was 284%.
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: High Peak to Average Power Ratio (PAPR) of the
transmitted signal is a serious problem in multicarrier systems (MC),
such as Orthogonal Frequency Division Multiplexing (OFDM), or in
Multi-Carrier Code Division Multiple Access (MC-CDMA) systems,
due to large number of subcarriers. This effect is possible reduce with
some PAPR reduction techniques. Spreading sequences at the
presence of Saleh and Rapp models of high power amplifier (HPA)
have big influence on the behavior of system. In this paper we
investigate the bit-error-rate (BER) performance of MC-CDMA
systems. Basically we can see from simulations that the MC-CDMA
system with Iterative algorithm can be providing significantly better
results than the MC-CDMA system. The results of our analyses are
verified via simulation.
Abstract: Iris codes contain bits with different entropy. This
work investigates different strategies to reduce the size of iris
code templates with the aim of reducing storage requirements and
computational demand in the matching process. Besides simple subsampling
schemes, also a binary multi-resolution representation as
used in the JBIG hierarchical coding mode is assessed. We find that
iris code template size can be reduced significantly while maintaining
recognition accuracy. Besides, we propose a two-stage identification
approach, using small-sized iris code templates in a pre-selection
stage, and full resolution templates for final identification, which
shows promising recognition behaviour.
Abstract: Member States shall establish zones and
agglomerations throughout their territory to assess and manage air
quality in order to comply with European directives.
In Italy decree 155/2010, transposing Directive 2008/50/EC on
ambient air quality and cleaner air for Europe, merged into a single
act the previous provisions on ambient air quality assessment and
management, including those resulting from the implementation of
Directive 2004/107/EC relating to arsenic, cadmium, nickel, mercury
and polycyclic aromatic hydrocarbons in ambient air.
Decree 155/2010 introduced stricter rules for identifying zones on
the basis of the characteristics of the territory in spite of considering
pollution levels, as it was in the past. The implementation of such
new criteria has reduced the great variability of the previous zoning,
leading to a significant reduction of the total number of zones and to
a complete and uniform ambient air quality assessment and
management throughout the Country.
The present document is related to the new zones definition in
Italy according to Decree 155/2010. In particular the paper contains
the description and the analysis of the outcome of zoning and
classification.
Abstract: Conventional educational practices, do not offer all
the required skills for teachers to successfully survive in today’s
workplace. Due to poor professional training, a big gap exists across
the curriculum plan and the teacher practices in the classroom. As
such, raising the quality of teaching through ICT-enabled training and
professional development of teachers should be an urgent priority.
‘Mobile Learning’, in that vein, is an increasingly growing field of
educational research and practice across schools and work places. In
this paper, we propose a novel Mobile learning system that allows the
users to learn through an intelligent mobile learning in cooperatively
every-time and every-where. The system will reduce the training cost
and increase consistency, efficiency, and data reliability. To establish
that our system will display neither functional nor performance
failure, the evaluation strategy is based on formal observation of
users interacting with system followed by questionnaires and
structured interviews.
Abstract: Fracture in hot precision forging of engine valves was
investigated in this paper. The entire valve forging procedure was
described and the possible cause of the fracture was proposed. Finite
Element simulation was conducted for the forging process, with
commercial Finite Element code DEFORMTM. The effects of
material properties, the effect of strain rate and temperature were
considered in the FE simulation. Two fracture criteria were discussed
and compared, based on the accuracy and reliability of the FE
simulation results. The selected criterion predicted the fracture
location and shows the trend of damage increasing with good
accuracy, which matches the experimental observation. Additional
modification of the punch shapes was proposed to further reduce the
tendency of fracture in forging. Finite Element comparison shows a
great potential of such application in the mass production.