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: Large-scale data stream analysis has become one of
the important business and research priorities lately. Social networks
like Twitter and other micro-blogging platforms hold an enormous
amount of data that is large in volume, velocity and variety.
Extracting valuable information and trends out of these data would
aid in a better understanding and decision-making. Multiple analysis
techniques are deployed for English content. Moreover, one of the
languages that produce a large amount of data over social networks
and is least analyzed is the Arabic language. The proposed paper is a
survey on the research efforts to analyze the Arabic content in
Twitter focusing on the tools and methods used to extract the
sentiments for the Arabic content on Twitter.
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: 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: Estimation of model parameters is necessary to predict
the behavior of a system. Model parameters are estimated using
optimization criteria. Most algorithms use historical data to estimate
model parameters. The known target values (actual) and the output
produced by the model are compared. The differences between the
two form the basis to estimate the parameters. In order to compare
different models developed using the same data different criteria are
used. The data obtained for short scale projects are used here. We
consider software effort estimation problem using radial basis
function network. The accuracy comparison is made using various
existing criteria for one and two predictors. Then, we propose a new
criterion based on linear least squares for evaluation and compared
the results of one and two predictors. We have considered another
data set and evaluated prediction accuracy using the new criterion.
The new criterion is easy to comprehend compared to single statistic.
Although software effort estimation is considered, this method is
applicable for any modeling and prediction.
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: 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: Qatar, a Gulf country highly dependent on its oil and
gas revenues – is looking to innovate, diversify, and ultimately reach
its aim of creating a knowledge economy to prepare for its post-oil
era. One area that the country is investing in is Contemporary Art,
and world renowned artists such as Damien Hirst and Richard Serra –
have been commissioned to design site-specific art for the public
spaces of the city of Doha as well as in more remote desert locations.
This research discusses the changing presence, role and context of
public art in Doha, both from a historical and cultural overview, and
the different forms and media as well as the typologies of urban and
public spaces in which the art is installed. It examines the process of
implementing site-specific artworks, looking at questions of scale,
history, social meaning and formal aesthetics. The methodologies
combine theoretical research on the understanding of public art and
its role and placement in public space, as well as empirical research
on contemporary public art projects in Doha, based on documentation
and interviews and as well as site and context analysis of the urban or
architectural spaces within which the art is situated. Surveys and
interviews – using social media - in different segments of the
contemporary Qatari society, including all nationalities and social
groups, are used to measure and qualify the impacts and effects on
the population.
Abstract: Macro invertebrates have been used to monitor
organic pollution in rivers and streams. Several biotic indices based
on macro invertebrates have been developed over the years including
the Biological Monitoring Working Party (BMWP). A new biotic
index, the Gammarus:Asellus ratio has been recently proposed as an
index of organic pollution. This study tested the validity of the
Gammarus:Asellus ratio as an index of organic pollution, by
examining the relationship between the Gammarus:Asellus ratio and
physical chemical parameters, and other biotic indices such as
BMWP and, Average Score Per Taxon (ASPT) from lakes and
streams at Markeaton Park, Allestree Park and Kedleston Hall,
Derbyshire. Macro invertebrates were sampled using the standard
five minute kick sampling techniques physical and chemical
environmental variables were obtained based on standard sampling
techniques. Eighteen sites were sampled, six sites from Markeaton
Park (three sites across the stream and three sites across the lake). Six
sites each were also sampled from Allestree Park and Kedleston Hall
lakes. The Gammarus:Asellus ratio showed an opposite significant
positive correlations with parameters indicative of organic pollution
such as the level of nitrates, phosphates, and calcium and also
revealed a negatively significant correlations with other biotic indices
(BMWP/ASPT). The BMWP score correlated positively significantly
with some water quality parameters such as dissolved oxygen and
flow rate, but revealed no correlations with other chemical
environmental variables. The BMWP score was significantly higher
in the stream than the lake in Markeaton Park, also The ASPT scores
appear to be significantly higher in the upper Lakes than the middle
and lower lakes. This study has further strengthened the use of
BMWP/ASPT score as an index of organic pollution. But additional
application is required to validate the use of Gammarus:Asellus as a
rapid bio monitoring tool.
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.
Abstract: Speech Segmentation is the measure of the change
point detection for partitioning an input speech signal into regions
each of which accords to only one speaker. In this paper, we apply
two features based on multi-scale product (MP) of the clean speech,
namely the spectral centroid of MP, and the zero crossings rate of
MP. We focus on multi-scale product analysis as an important tool
for segmentation extraction. The MP is based on making the product
of the speech wavelet transform coefficients (WTC). We have
estimated our method on the Keele database. The results show the
effectiveness of our method. It indicates that the two features can find
word boundaries, and extracted the segments of the clean speech.
Abstract: Recently, universities are increasingly consuming
energy to support various activities. A large population of staff and
students in Malaysian universities has led to excessive energy
consumption which directly gives an impact to the environment. The
key question then ascended “How well is an energy management
(EM) been practiced in universities without taking the Critical
Success Factors (CSFs) into consideration to ensure the management
of university achieves the goals in reducing energy consumption.
Review on past literature is carried out to establish CSFs for EM best
practices. Thus, this paper highlighted the CSFs which have to be
focused on by management of university to successfully measure the
EM implementation and its performance. At the end of this paper, a
theoretical framework is developed for EM success factors towards
sustainable university.
Abstract: Neurons in the nervous system communicate with
each other by producing electrical signals called spikes. To
investigate the physiological function of nervous system it is essential
to study the activity of neurons by detecting and sorting spikes in the
recorded signal. In this paper a method is proposed for considering
the spike sorting problem which is based on the nonlinear modeling
of spikes using exponential autoregressive model. The genetic
algorithm is utilized for model parameter estimation. In this regard
some selected model coefficients are used as features for sorting
purposes. For optimal selection of model coefficients, self-organizing
feature map is used. The results show that modeling of spikes with
nonlinear autoregressive model outperforms its linear counterpart.
Also the extracted features based on the coefficients of exponential
autoregressive model are better than wavelet based extracted features
and get more compact and well-separated clusters. In the case of
spikes different in small-scale structures where principal component
analysis fails to get separated clouds in the feature space, the
proposed method can obtain well-separated cluster which removes
the necessity of applying complex classifiers.
Abstract: The aim of this study is to evaluate the effects of the
laser and partial vibration stimulation on the mice tibia with
morphological characteristics. Twenty female C57BL/6 mice (12
weeks old) were used for the experiment. The study was carried out on
four groups of animals each consisting of five mice. Four groups of
mice were ovariectomized. Animals were scanned at 0 and 2 weeks
after ovariectomy by using micro computed tomography to estimate
morphological characteristics of tibial trabecular bone. Morphological
analysis showed that structural parameters of multi-stimuli group
appear significantly better phase in BV/TV, BS/BV, Tb.Th, Tb.N,
Tb.Sp, and Tb.pf than single stimulation groups. However, single
stimulation groups didn’t show significant effect on tibia with Sham
group. This study suggests that multi-stimuli may restrain the change
as the degenerate phase on osteoporosis in the mice tibia.
Abstract: These days, the field of tissue engineering is getting
serious attention due to its usefulness. Bone tissue engineering helps
to address and sort-out the critical sized and non-healing orthopedic
problems by the creation of manmade bone tissue. We will design
and validate an efficient numerical model, which will simulate the
effective diffusivity in bone tissue engineering. Our numerical model
will be based on the finite element analysis of the diffusion-reaction
equations. It will have the ability to optimize the diffusivity, even
at multi-scale, with the variation of time. It will also have a special
feature “parametric sweep”, with which we will be able to predict
the oxygen, glucose and cell density dynamics, more accurately. We
will fix these problems by modifying the governing equations, by
selecting appropriate spatio-temporal finite element schemes and by
transient analysis.
Abstract: Stator elements «Vane diffuser + crossover + return
channel» of stages with different specific speed were investigated by
CFD calculations. The regime parameter was introduced to present
efficiency and loss coefficient performance of all elements together.
Flow structure demonstrated advantages and disadvantages of design.
Flow separation in crossovers was eliminated by its shape
modification. Efficiency increased visibly. Calculated CFD
performances are in acceptable correlation with predicted ones by
engineering design method. The information obtained is useful for
design method better calibration.
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.