Abstract: In this numerical study, effects of using Al2O3-water
nanofluid on the rate of heat transfer have been investigated. Physical
model is a square enclosure with insulated top and bottom horizontal
walls, while the vertical walls are kept at different constant
temperatures. Two appropriate models are used to evaluate the
viscosity and thermal conductivity of nanofluid. The governing
stream-vorticity equations are solved using a second order central
finite difference scheme, coupled to the conservation of mass and
energy. The study has been carried out for the nanoparticle diameter
30, 60 and 90 nm and the solid volume fraction 0 to 0.04. Results are
presented by average Nusselt number and normalized Nusselt number
in different range of φ and D for mixed convection dominated
regime. It is found that different heat transfer rate is predicted when
the effect of nanoparticle diameter is taken into account.
Abstract: Government reports and published research have
flagged and brought to public attention the deteriorating condition of
a large percentage of bridges in Canada and the United States. With
the increasing number of deteriorated bridges in the US, Canada, and
around the globe, condition assessment techniques of concrete
bridges are evolving. Investigation for bridges’ defects such as
cracks, spalls, and delamination and their level of severity are the
main objectives of condition assessment. Inspection and
rehabilitation programs are being implemented to monitor and
maintain deteriorated bridge infrastructure. This paper highlights the
state-of-the art of current practices being performed for concrete
bridge inspection. The information is gathered from the literature and
through a distributed questionnaire. The current practices in concrete
bridge inspection rely on the use of hummer sounding and chain
dragging tests. Non-Destructive Testing (NDT) techniques are not
being utilized fully in the process. Nonetheless, they are being
partially utilized by the recommendation of the bridge inspector after
conducting visual inspection. Lanes are usually closed during the
performance of visual inspection and bridge inspection in general.
Abstract: This study aims to assess the students' needs for the
tour planning e-guide. The study is developing on the contribution
and importance of the Educational Tour Planning Guide (ETP) is a
multimedia course ware as one of the effective methods in teaching
and learning of environmental science among the students in primary
schools of the Ministry of Education, Malaysia. It is to provide the
student with knowledge and experience about tourism, environmental
science activities and process. E-guide to ETP also hopes to
strengthen the student understanding toward the subject learn in the
tourism environmental science. In order to assess the student's needs
on the e-Guide to Educational Tour Planning in Environmental
Science, the study has produced a similar e-Guide to ETP in the form
as a course ware to be tested during the study. The study has involved
several steps in order to be completed. It is such as the formulation of
the problem, the review of the literature, the formulation of the study
methodology, the production of the e-Guide to ETP, field survey and
finally the analyses and discussion made on the data gathered during
the study. The survey has involved 100 respondents among the
students in standard six primary schools in Kluang Johor. Through
the findings, the study indicates that the current tested product is
acceptable among the students in learning environmental science as a
guide to plan for the tour. The findings also show a slight difference
between the respondents who are using the e-Guide to ETP, and those
who are not on the basis of the e-Guide to ETP results. Due the
important for the study, the researcher hopes to be having a fair
discussion and excellence, recommendation for the development of
the product of the current study. This report is written also important
to provide a written reference for the future related study.
Abstract: The aim of this study is to identify the suitability of
Virtual Learning Environment (VLE) in welding simulator
application towards Computer-Based Training (CBT) in developing
skills upon new students at the Advanced Technology Training
Center (ADTEC) Batu Pahat, Johor, Malaysia and GIATMARA,
Batu Pahat, Johor, Malaysia. The significance of the study is to create
a computer-based skills development approach in welding technology
among new students in ADTEC and GIATMARA as well as to
cultivate the elements of general skills among them. This study is
also important in elevating the number of individual knowledge
workers (K-workers) working in manufacturing industry in order to
achieve a national vision which is to be an industrial nation in the
year of 2020. The design of the study is a survey type of research
which using questionnaires as the instruments and some 136 students
from ADTEC and GIATMARA were interviewed. Descriptive
analysis is used to identify the frequency and mean values. The
findings of the study show that the welding technology has developed
skills in the students because of the application of VLE simulated at a
high level and the respondents agreed that the skills could be
embedded through the application of the VLE simulator. In summary,
the VLE simulator is suitable in welding skills development training
in terms of exposing new students with the relevant characteristics of
welding skills and at the same time spurring the students’ interest
towards learning more about the skills.
Abstract: This study was conducted to investigate the extent
with which knowledge of results influences the performance of
cricket players. A sample of 160 fresh students in the Department of
Physical and Health Education who are novice in the game were
randomly assigned into two groups. The first group of eighty (80)
subjects was classified as experimental group while the second group
of eighty (80) subjects was the control group. Subjects in both groups
were asked to bowl and bat ten times each for a period of six weeks.
After the first round, the subjects in the experimental group were
allowed feedback on their performance in the first trial while those in
the control group were denied feedback. Two null hypotheses
generated for the study were tested using percentages and chi-square
statistical analysis at 0.05 level of significance. Analysis of data
showed that knowledge of results influenced the performance of
cricket players. It was concluded that knowledge of results is
pertinent for effective skill acquisition and could enhance better
performance among unskilled cricket players. Hence, it is suggested
that immediate feedback on the level of skill acquisition by the
prospective and unskilled cricket players would inspire them for
better performance in cricket tournaments.
Abstract: Polylactic acid (PLA) is the most commercially
available bio-based and biodegradable plastic at present. PLA has
been used in plastic related industries including single-used
containers, disposable and environmentally friendly packaging owing
to its renewability, compostability, biodegradability, and safety.
Although PLA demonstrates reasonably good optical, physical,
mechanical and barrier properties comparable to the existing
petroleum-based plastics, its brittleness and mold shrinkage as well as
its price are the points to be concerned for the production of rigid and
semi-rigid packaging. Blending PLA with other bio-based polymers
including thermoplastic starch (TPS) is an alternative not only to
achieve a complete bio-based plastic, but also to reduce the
brittleness, shrinkage during molding and production cost of the
PLA-based products. TPS is a material produced mainly from starch
which is cheap, renewable, biodegradable, compostable, and nontoxic.
It is commonly prepared by a plasticization of starch under
applying heat and shear force. Although glycerol has been reported as
one of the most plasticizers used for preparing TPS, its migration
caused the surface stickiness of the TPS products. In some cases,
mixed plasticizers or natural fibers have been applied to impede the
retrogradation of starch or reduce the migration of glycerol. The
introduction of fibers into TPS-based materials could reinforce the
polymer matrix as well. Therefore, the objective of the present
research is to study the effect of starch type (i.e. native starch and
phosphate starch), plasticizer type (i.e. glycerol and xylitol with a
weight ratio of glycerol to xylitol of 100:0, 75:25, 50:50, 25:75 and
0:100) and fiber content (i.e. in the range of 1-25 %wt) on properties
of PLA/TPS blend and composite. PLA/TPS blends and composites
were prepared using a twin-screw extruder and then converted into
dumbbell-shaped specimens using an injection molding machine. The
PLA/TPS blends prepared by using phosphate starch showed higher
tensile strength and stiffness than the blends prepared by using native
one. In contrast, the blends from native starch exhibited higher
extensibility and heat distortion temperature (HDT) than those from
the modified starch. Increasing xylitol content resulted in enhanced
tensile strength, stiffness and water resistance, but decreased
extensibility and HDT of the PLA/TPS blend. Tensile properties and
hydrophobicity of the blend could be improved by incorporating
silane treated-jute fibers.
Abstract: Household waste form a larger proportion of waste
generated across the state, accumulation of organic waste is an
apparent problem and the existing dump sites could be overstress.
Niger state has abundant arable land and water resources thus should
be one of the highest producers of agricultural crops in the country.
However, the major challenge to agricultural sector today is loss of
soil nutrient coupled with high cost of fertilizer. These have
continued to increase the use of fertilizer and decomposed solid waste
for enhance agricultural yield, which have varying effects on the soil
as well a threat to human livelihood. Consequently, vegetable yield
samples from poultry droppings, decomposed household waste
manure, NPK treatments and control from each replication were
subjected to proximate analysis to determine the nutritional and antinutritional
component as well as heavy metal concentration. Data
collected was analyzed using SPSS software and Randomized
complete Block Design means were compared. The result shows that
the treatments do not devoid the concentrations of any nutritional
components while the anti-nutritional analysis proved that NPK had
higher oxalate content than control and organic treats. The
concentration of lead and cadmium are within safe permissible level
while the mercury level exceeded the FAO/WHO maximum
permissible limit for the entire treatments depicts the need for urgent
intervention to minimize mercury levels in soil and manure in order
to mitigate its toxic effect. Thus, eco-agriculture should be widely
accepted and promoted by the stakeholders for soil amendment,
higher yield, strategies for sustainable environmental protection, food
security, poverty eradication, attainment of sustainable development
and healthy livelihood.
Abstract: In IA-MDT, the magnetic implants are placed
strategically at the target site to greatly and locally increase the
magnetic force on MDCPs and help to attract and retain the MDCPs
at the targeted region. In the present work, we develop a
mathematical model to study the capturing of magnetic nanoparticles
flowing within a fluid in an implant assisted cylindrical channel
under magnetic field. A coil of ferromagnetic SS-430 has been
implanted inside the cylindrical channel to enhance the capturing of
magnetic nanoparticles under magnetic field. The dominant magnetic
and drag forces, which significantly affect the capturing of
nanoparticles, are incorporated in the model. It is observed through
model results that capture efficiency increases as we increase the
magnetic field from 0.1 to 0.5 T, respectively. The increase in capture
efficiency by increase in magnetic field is because as the magnetic
field increases, the magnetization force, which is attractive in nature
and responsible to attract or capture the magnetic particles, increases
and results the capturing of large number of magnetic particles due to
high strength of attractive magnetic force.
Abstract: Nowadays, illegal logging has been causing many
effects including flash flood, avalanche, global warming, and etc. The
purpose of this study was to maintain the earth ecosystem by keeping
and regulate Malaysia’s treasurable rainforest by utilizing a new
technology that will assist in real-time alert and give faster response
to the authority to act on these illegal activities. The methodology of
this research consisted of design stages that have been conducted as
well as the system model and system architecture of the prototype in
addition to the proposed hardware and software that have been
mainly used such as microcontroller, sensor with the implementation
of GSM, and GPS integrated system. This prototype was deployed at
Royal Belum forest in December 2014 for phase 1 and April 2015 for
phase 2 at 21 pinpoint locations. The findings of this research were
the capture of data in real-time such as temperature, humidity,
gaseous, fire, and rain detection which indicate the current natural
state and habitat in the forest. Besides, this device location can be
detected via GPS of its current location and then transmitted by SMS
via GSM system. All of its readings were sent in real-time for further
analysis. The data that were compared to meteorological department
showed that the precision of this device was about 95% and these
findings proved that the system is acceptable and suitable to be used
in the field.
Abstract: The Greater Athens Area (GAA) faces photochemical
and particulate pollution episodes as a result of the combined effects
of local pollutant emissions, regional pollution transport, synoptic
circulation and topographic characteristics. The area has undergone
significant changes since the Athens 2004 Olympic Games because
of large scale infrastructure works that lead to the shift of population
to areas previously characterized as rural, the increase of the traffic
fleet and the operation of highways. However, few recent modelling
studies have been performed due to the lack of an accurate, updated
emission inventory. The photochemical modelling system
MM5/CAMx was applied in order to study the photochemical and
particulate pollution characteristics above the GAA for two distinct
ten-day periods in the summer of 2006 and 2010, where air pollution
episodes occurred. A new updated emission inventory was used
based on official data. Comparison of modeled results with
measurements revealed the importance and accuracy of the new
Athens emission inventory as compared to previous modeling
studies. The model managed to reproduce the local meteorological
conditions, the daily ozone and particulates fluctuations at different
locations across the GAA. Higher ozone levels were found at
suburban and rural areas as well as over the sea at the south of the
basin. Concerning PM10, high concentrations were computed at the
city centre and the southeastern suburbs in agreement with measured
data. Source apportionment analysis showed that different sources
contribute to the ozone levels, the local sources (traffic, port
activities) affecting its formation.
Abstract: This study focuses on the hydro-geology and chemical
constituents analysis of Ikogosi Warm Spring waters in South West
Nigeria. Ikogosi warm spring is a global tourist attraction because it
has both warm and cold spring sources. Water samples from the cold
spring, warm spring and the meeting point were collected, analyzed
and the result shows close similarity in temperature, hydrogen iron
concentration (pH), alkalinity, hardness, Calcium, Magnesium,
Sodium, Iron, total dissolved solid and heavy metals. The measured
parameters in the water samples are within World Health
Organisation standards for fresh water. The study of the geology of
the warm spring reveals that the study area is underlain by a group of
slightly migmatised to non-migmatised paraschists and meta-igneous
rocks. Also, concentration levels of selected heavy metals, (Copper,
Cadmium, Zinc, Arsenic and Cromium) were determined in the water
(ppm) samples. Chromium had the highest concentration value of
1.52ppm (an average of 49.67%) and Cadmium had the lowest
concentration with value of 0.15ppm (an average of 4.89%).
Comparison of these results showed that, their mean levels are within
the standard values obtained in Nigeria. It can be concluded that both
warm and spring water are safe for drinking.
Abstract: The present study deals with the characterization of
CrSiN coatings obtained by PVD magnetron sputtering systems.
CrSiN films were deposited with different Si contents, in order to
check the effect of at.% variation on the different properties of the
Cr–N system. Coatings were characterized by scanning electron
microscopy (SEM) for thickness measurements, X-ray diffraction.
Surface morphology and the roughness characteristics were explored
using AFM, Mechanicals properties, elastic and plastic deformation
resistance of thin films were investigated using nanoindentation test. We observed that the Si addition improved the hardness and the
Young’s modulus of the Cr–N system. Indeed, the hardness value is
18,56 GPa for CrSiN coatings. Besides, the Young’s modulus value
is 224,22 GPa for CrSiN coatings for Si content of 1.2 at.%.
Abstract: Extreme formation is a theoretical concept of selfsustain
flight when a big airliner is followed by a small UAV glider
flying in the airliner wake vortex. The paper presents results of a
climb analysis with the goal to lift the gliding UAV to airliners cruise
altitude. Wake vortex models, the UAV drag polar and basic
parameters and airliner’s climb profile are introduced at first.
Afterwards, flight performance of the UAV in a wake vortex is
evaluated by analytical methods. Time history of optimal distance
between an airliner and the UAV during a climb is determined. The
results are encouraging. Therefore available UAV drag margin for
electricity generation is figured out for different vortex models.
Abstract: The development of composite materials and the
related design and manufacturing technologies is one of the most
important advances in the history of materials. Composites are
multifunctional materials having unprecedented mechanical and
physical properties that can be tailored to meet the requirements of a
particular application. Some composites also exhibit great resistance
to high-temperature corrosion, oxidation, and wear. Polymers are
widely used indoors and outdoors, therefore they are exposed to a
chemical environment which may include atmospheric oxygen, acidic
fumes, acidic rain, moisture heat and thermal shock, ultra-violet light,
high energy radiation, etc. Different polymers are affected differently
by these factors even though the amorphous polymers are more
sensitive. Ageing is also important and it is defined as the process of
deterioration of engineering materials resulting from the combined
effects of atmospheric radiation, heat, oxygen, water, microorganisms
and other atmospheric factors.
Abstract: The present study focused on the investigation of the
effects of roughness elements on heat transfer during natural
convection in a rectangular cavity using numerical technique.
Roughness elements were introduced on the bottom hot wall with a
normalized amplitude (A*/H) of 0.1. Thermal and hydrodynamic
behaviors were studied using computational method based on Lattice
Boltzmann method (LBM). Numerical studies were performed for a
laminar flow in the range of Rayleigh number (Ra) from 103 to 106
for a rectangular cavity of aspect ratio (L/H) 2.0 with a fluid of
Prandtl number (Pr) 1.0. The presence of the sinusoidal roughness
elements caused a minimum to maximum decrease in the heat
transfer as 7% to 17% respectively compared to smooth enclosure.
The results are presented for mean Nusselt number (Nu), isotherms
and streamlines.
Abstract: The study conducted a simulation of the effect of sea
water to the bonding capacity of GFRP sheet on the concrete beams
using a simulation tank. Fiber reinforced polymer (FRP) has been
developed and applied in many fields civil engineering structures on
the new structures and also for strengthening of the deteriorated
structures. The FRP has advantages such as its corrosion resistance as
well as high tensile strength to weight ratio. Compared to the other
FRP materials, Glass composed FRP (GFRP) is relatively cheaper.
GFRP sheet is applied externally by bonding it on the concrete surface.
The studies regarding the application of GFRP sheet have been
conducted such as strengthening system, bonding behavior of GFRP
sheet including the application as reinforcement in new structures. For
application to the structures with direct contact to sea environment, a
study regarding the effect of sea water to the bonding capacity of
GFRP sheet is important to be clarified. To achieve the objective of the
study, a series of concrete beams strengthened with GFRP sheet on
extreme tension surface were prepared. The beams then were stored on
the sea water tank for six months. Results indicated the bonding
capacity decreased after six month exposed to the sea water.
Abstract: Modelling of building processes of a multimodal
freight transportation support information system is discussed based
on modern CASE technologies. Functional efficiencies of ports in
the eastern part of the Black Sea are analyzed taking into account
their ecological, seasonal, resource usage parameters. By resources,
we mean capacities of berths, cranes, automotive transport, as well as
work crews and neighbouring airports. For the purpose of designing
database of computer support system for Managerial (Logistics)
function, using Object-Role Modeling (ORM) tool (NORMA–Natural ORM Architecture) is proposed, after which Entity
Relationship Model (ERM) is generated in automated process.
Software is developed based on Process-Oriented and Service-Oriented architecture, in Visual Studio.NET environment.
Abstract: Carbon Fiber Reinforced Plastics (CFRPs) are widely
used for advanced applications, in particular in aerospace, automotive
and wind energy industries. Once cured to near net shape, CFRP
parts need several finishing operations such as trimming, milling or
drilling in order to accommodate fastening hardware and meeting the
final dimensions. The present research aims to study the effect of the
cutting temperature in trimming on the mechanical strength of high
performance CFRP laminates used for aeronautics applications. The
cutting temperature is of great importance when dealing with
trimming of CFRP. Temperatures higher than the glass-transition
temperature (Tg) of the resin matrix are highly undesirable: they
cause degradation of the matrix in the trimmed edges area, which can
severely affect the mechanical performance of the entire component.
In this study, a 9.50mm diameter CVD diamond coated carbide tool
with six flutes was used to trim 24-plies CFRP laminates. A
300m/min cutting speed and 1140mm/min feed rate were used in the
experiments. The tool was heated prior to trimming using a
blowtorch, for temperatures ranging from 20°C to 300°C. The
temperature at the cutting edge was measured using embedded KType
thermocouples. Samples trimmed for different cutting
temperatures, below and above Tg, were mechanically tested using
three-points bending short-beam loading configurations. New cutting
tools as well as worn cutting tools were utilized for the experiments.
The experiments with the new tools could not prove any correlation
between the length of cut, the cutting temperature and the mechanical
performance. Thus mechanical strength was constant, regardless of
the cutting temperature. However, for worn tools, producing a cutting
temperature rising up to 450°C, thermal damage of the resin was
observed. The mechanical tests showed a reduced mean resistance in
short beam configuration, while the resistance in three point bending
decreases with increase of the cutting temperature.
Abstract: The ferrites ZnFe2O4, CdFe2O4 and CuFe2O4 are
synthesized in laboratory conditions using ceramic technology. Their
homogeneity and structure are proven by X-Ray diffraction analysis
and Mössbauer spectroscopy. The synthesized ferrites are subjected
to strong acid and high temperature leaching with solutions of H2SO4,
HCl and HNO3. The results indicate that the highest degree of
leaching of Zn, Cd and Cu from the ferrites is achieved by use of
HCl. The charging of five zinc sulfide concentrates was optimized using
the criterion of minimal amount of zinc ferrite produced when
roasting the concentrates in a fluidized bed. The results obtained are
interpreted in terms of the hydrometallurgical zinc production and
maximum recovery of zinc, copper and cadmium from initial zinc
concentrates after their roasting.
Abstract: In order to be capable of dealing with uncertainties,
subjectivities, including vagueness arising in building construction
projects, the application of fuzzy reasoning technique based on fuzzy
set theory is proposed. This study contributes significantly to the
development of a fuzzy reasoning safety risk assessment model for
building construction projects that could be employed to assess the
risk magnitude of each hazardous event identified during
construction, and a third parameter of probability of consequence is
incorporated in the model. By using the proposed safety risk analysis
methodology, more reliable and less ambiguities, which provide the
safety risk management project team for decision-making purposes.