Abstract: The present work deals with analyses of the effects
of bearing curvature and non-Newtonian characteristics on the load capacity of an exponential rectangular squeeze film bearing using
Bingham fluids as lubricants. Bingham fluids are characterized by an
yield value and hence the formation of a “rigid" core in the region
between the plates is justified. The flow is confined to the region
between the core and the plates. The shape of the core has been
identified through numerical means. Further, numerical solutions for
the pressure distribution and load carrying capacity of the bearing
for various values of Bingham number and curvature parameter have
been obtained. The effects of bearing curvature and non-Newtonian
characteristics of the lubricant on the bearing performances have been
discussed.
Abstract: This article is focused on the calculation of heat
radiation intensity and its optimization on an aluminum mould
surface. The inside of the mould is sprinkled with a special powder
and its outside is heated by infra heaters located above the mould
surface, up to a temperature of 250°C. By this way artificial leathers
in the car industry are produced (e. g. the artificial leather on a car
dashboard). A mathematical model of heat radiation of infra heaters
on a mould surface is described in this paper. This model allows us to
calculate a heat-intensity radiation on the mould surface for the
concrete location of infra heaters above the mould surface. It is
necessary to ensure approximately the same heat intensity radiation
on the mould surface by finding a suitable location for the infra
heaters, and in this way the same material structure and color of
artificial leather. In the model we have used a genetic algorithm to
optimize the radiation intensity on the mould surface. Experimental
measured values for the heat radiation intensity by a sensor in the
surroundings of an infra heater are used for the calculation
procedures. A computational procedure was programmed in language
Matlab.
Abstract: The range of the output power is a very important and evident limitation of two-level inverters. In order to overcome this disadvantage, multilevel inverters are introduced. Recently, Cascade H-Bridge inverters have emerged as one of the popular converter topologies used in numerous industrial applications. The modulation switching strategies such as phase shifted carrier based Pulse Width Modulation (PWM) technique and Stair case modulation with Selective Harmonic Elimination (SHE) PWM technique are generally used. NR method is used to solve highly non linear transcendental equations which are formed by SHEPWM method. Generally NR method has a drawback of requiring good initial guess but in this paper a new approach is implemented for NR method with any random initial guess. A three phase CHB 11-level inverter is chosen for analysis. MATLAB/SIMULINK programming environment and harmonic profiles are compared. Finally this paper presents a method at fundamental switching frequency with least % THDV.
Abstract: In the paper the research of flat textile products for use
as electrodes was presented. Material-s resistance measurements were
carried out to determine the suitability of the textiles. Based on the received results of studies different types of textile electrodes were
designed. Textile electrodes tests were carried out on human
phantoms. The electro-conductive properties of human forearm
phantom were also described. Based on this results special electroconductive
hydrogels with electro-conductive particles were feasible. The hydrogel is an important element of the forearm-s phantom
model of a survey of electrodes for muscle electrostimulation. The
hydrogel is an equivalent human skin and tissue. The hydrogel should
have a permanence and recurrence of the electro-conductive properties.
Abstract: Islam has a general principle of increase in
population. But the Muslims are equally obliged to take care of
health, education and the provisions etc. for their offspring and wives
in the best possible way. The Muslims would have to regulate and
manage the number of children, if any situation affects their duties
regarding their wives or children. Islam accomplishes permissibility
of temporary blockade in human fertility if someone faces any
problem regarding health of mother or children. During the life of the
Holy Prophet (SAW), Azl (coitus interruptus) was the only way for
temporary spacing between the children. In technologically
developed environment, the same can be resort through some
advanced methodology or instrument of temporary blockade. Solid
grounds are available in Islam that the fertility rate should be
managed if any of the aspect of human quality is being affected.
Abstract: A high performance clarification system has been
discussed for advanced aqueous reprocessing of FBR spent fuel.
Dissolver residue gives the cause of troubles on the plant operation of
reprocessing. In this study, the new clarification system based on the
hybrid of centrifuge and filtration was proposed to get the high
separation ability of the component of whole insoluble sludge. The
clarification tests of simulated solid species were carried out to
evaluate the clarification performance using small-scale test apparatus
of centrifuge and filter unit. The density effect of solid species on the
collection efficiency was mainly evaluated in the centrifugal
clarification test. In the filtration test using ceramic filter with pore
size of 0.2μm, on the other hand, permeability and filtration rate
were evaluated in addition to the filtration efficiency. As results, it was
evaluated that the collection efficiency of solid species on the new
clarification system was estimated as nearly 100%. In conclusion, the
high clarification performance of dissolver liquor can be achieved by
the hybrid of the centrifuge and filtration system.
Abstract: A zero dimensional model has been used to investigate
the combustion performance of a single cylinder direct injection
diesel engine fueled by biofuels with options like supercharging and
exhaust gas recirculation. The numerical simulation was performed at
constant speed. The indicated pressure, temperature diagrams are
plotted and compared for different fuels. The emissions of soot and
nitrous oxide are computed with phenomenological models. The
experimental work was also carried out with biodiesel (palm stearin
methyl ester) diesel blends, ethanol diesel blends to validate
simulation results with experimental results, and observed that the
present model is successful in predicting the engine performance with
biofuels.
Abstract: The aim of this work is to study the possible use of
stone cutting sludge waste in concrete production, which would
reduce both the environmental impact and the production cost .Slurry
sludge was used a source of water in concrete production, which was
obtained from Samara factory/Jordan, The physico-chemical and
mineralogical characterization of the sludge was carried out to
identify the major components and to compare it with the typical
sand used to produce concrete. Samples analysis showed that 96% of
slurry sludge volume is water, so it should be considered as an
important source of water. Results indicated that the use of slurry
sludge as water source in concrete production has insignificant effect
on compression strength, while it has a sharp effect on the slump
values. Using slurry sludge with a percentage of 25% of the total
water content obtained successful concrete samples regarding slump
and compression tests. To clarify slurry sludge, settling process can
be used to remove the suspended solid. A settling period of 30 min.
obtained 99% removal efficiency. The clarified water is suitable for
using in concrete mixes, which reduce water consumption, conserve
water recourses, increase the profit, reduce operation cost and save
the environment. Additionally, the dry sludge could be used in the
mix design instead of the fine materials with sizes < 160 um. This
application could conserve the natural materials and solve the
environmental and economical problem caused by sludge
accumulation.
Abstract: One of the vital developmental tasks that an
individual faces during adolescence is choosing a career. Arriving at
a career decision is difficult and anxious for many adolescents in the
tertiary level. The main purpose of this study is to determine the
factors relating to career indecision among freshmen college students
as basis for the formulation of a comprehensive career counseling
program for the psychological well-being of freshmen university
students. The subjects were purposively selected. The Slovin-s
formula was used in determining the sample size, using a 0.05
margin of error in getting the total number of samples per college and
per major. The researcher made use of descriptive correlational study
in determining significant factors relating to career indecision.
Multiple Regression Analysis indicated that career thoughts, career
decisions and vocational identity as factors related to career
indecision.
Abstract: Evaluation of contact pressure, surface and
subsurface contact stresses are essential to know the functional
response of surface coatings and the contact behavior mainly depends
on surface roughness, material property, thickness of layer and the
manner of loading. Contact parameter evaluation of real rough
surface contacts mostly relies on statistical single asperity contact
approaches. In this work, a three dimensional layered solid rough
surface in contact with a rigid flat is modeled and analyzed using
finite element method. The rough surface of layered solid is
generated by FFT approach. The generated rough surface is exported
to a finite element method based ANSYS package through which the
bottom up solid modeling is employed to create a deformable solid
model with a layered solid rough surface on top. The discretization
and contact analysis are carried by using the same ANSYS package.
The elastic, elastoplastic and plastic deformations are continuous in
the present finite element method unlike many other contact models.
The Young-s modulus to yield strength ratio of layer is varied in the
present work to observe the contact parameters effect while keeping
the surface roughness and substrate material properties as constant.
The contacting asperities attain elastic, elastoplastic and plastic states
with their continuity and asperity interaction phenomena is inherently
included. The resultant contact parameters show that neighboring
asperity interaction and the Young-s modulus to yield strength ratio
of layer influence the bulk deformation consequently affect the
interface strength.
Abstract: Natural gas is the most popular fossil fuel in the
current era and future as well. Natural gas is existed in underground
reservoirs so it may contain many of non-hydrocarbon components
for instance, hydrogen sulfide, nitrogen and water vapor. These
impurities are undesirable compounds and cause several technical
problems for example, corrosion and environment pollution.
Therefore, these impurities should be reduce or removed from natural
gas stream. Khurmala dome is located in southwest Erbil-Kurdistan
region. The Kurdistan region government has paid great attention for
this dome to provide the fuel for Kurdistan region. However, the
Khurmala associated natural gas is currently flaring at the field.
Moreover, nowadays there is a plan to recover and trade this gas and
to use it either as feedstock to power station or to sell it in global
market. However, the laboratory analysis has showed that the
Khurmala sour gas has huge quantities of H2S about (5.3%) and CO2
about (4.4%). Indeed, Khurmala gas sweetening process has been
removed in previous study by using Aspen HYSYS. However,
Khurmala sweet gas still contents some quintets of water about 23
ppm in sweet gas stream. This amount of water should be removed or
reduced. Indeed, water content in natural gas cause several technical
problems such as hydrates and corrosion. Therefore, this study aims
to simulate the prospective Khurmala gas dehydration process by
using Aspen HYSYS V. 7.3 program. Moreover, the simulation
process succeeded in reducing the water content to less than 0.1ppm.
In addition, the simulation work is also achieved process
optimization by using several desiccant types for example, TEG and
DEG and it also study the relationship between absorbents type and
its circulation rate with HCs losses from glycol regenerator tower.
Abstract: The purpose of this study was to investigate effects of
modality and redundancy principles on music theory learning among
pupils of different anxiety levels. The lesson of music theory was
developed in three different modes, audio and image (AI), text with
image (TI) and audio with image and text (AIT). The independent
variables were the three modes of courseware. The moderator
variable was the anxiety level, while the dependent variable was the
post test score. The study sample consisted of 405 third-grade pupils.
Descriptive and inferential statistics were conducted to analyze the
collected data. Analyses of covariance (ANCOVA) and Post hoc
were carried out to examine the main effects as well as the
interaction effects of the independent variables on the dependent
variable. The findings of this study showed that medium anxiety
pupils performed significantly better than low and high anxiety
pupils in all the three treatment modes. The AI mode was found to
help pupils with high anxiety significantly more than the TI and AIT
modes.
Abstract: Air conditioning is mainly use as human comfort
cooling medium. It use more in high temperatures are country such as
Malaysia. Proper estimation of cooling load will archive ideal
temperature. Without proper estimation can lead to over estimation or
under estimation. The ideal temperature should be comfort enough.
This study is to develop a program to calculate an ideal cooling load
demand, which is match with heat gain. Through this study, it is easy
to calculate cooling load estimation. Objective of this study are to
develop user-friendly and easy excess cooling load program. This is
to insure the cooling load can be estimate by any of the individual
rather than them using rule-of-thumb. Developed software is carryout
by using Matlab-GUI. These developments are only valid for
common building in Malaysia only. An office building was select as
case study to verify the applicable and accuracy of develop software.
In conclusion, the main objective has successfully where developed
software is user friendly and easily to estimate cooling load demand.
Abstract: This paper presents a method for determining the
uniaxial tensile properties such as Young-s modulus, yield strength
and the flow behaviour of a material in a virtually non-destructive
manner. To achieve this, a new dumb-bell shaped miniature
specimen has been designed. This helps in avoiding the removal of
large size material samples from the in-service component for the
evaluation of current material properties. The proposed miniature
specimen has an advantage in finite element modelling with respect
to computational time and memory space. Test fixtures have been
developed to enable the tension tests on the miniature specimen in a
testing machine. The studies have been conducted in a chromium
(H11) steel and an aluminum alloy (AR66). The output from the
miniature test viz. load-elongation diagram is obtained and the finite
element simulation of the test is carried out using a 2D plane stress
analysis. The results are compared with the experimental results. It is
observed that the results from the finite element simulation
corroborate well with the miniature test results. The approach seems
to have potential to predict the mechanical properties of the
materials, which could be used in remaining life estimation of the
various in-service structures.
Abstract: This paper explores the knowledge and attitude of
women and men in decision making on pap smear screening. This
qualitative study recruited 52 respondents with 44 women and 8 men,
using the purposive sampling with snowballing technique through indepth
interviews. This study demonstrates several key findings:
Female respondents have better knowledge compared to male. Most
of the women perceived that pap smear screening is beneficial and
important, but to proceed with the test is still doubtful. Male
respondents were supportive in terms of sending their spouses to the
health facilities or give more freedom to their wives to choose and
making decision on their own health due to prominent reason that
women know best on their own health. It is expected that the results
from this study will provide useful guideline for healthcare providers
to prepare any action/intervention to provide an extensive education
to improve people-s knowledge and attitude towards pap smear.
Abstract: Ethanol has been known for a long time, being
perhaps the oldest product obtained through traditional biotechnology
fermentation. Agriculture waste as substrate in fermentation is vastly
discussed as alternative to replace edible food and utilization of
organic material. Pineapple peel, highly potential source as substrate
is a by-product of the pineapple processing industry. Bio-ethanol
from pineapple (Ananas comosus) peel extract was carried out by
controlling fermentation without any treatment. Saccharomyces
ellipsoides was used as inoculum in this fermentation process as it is
naturally found at the pineapple skin. In this study, the capability of
Response Surface Methodology (RSM) for optimization of ethanol
production from pineapple peel extract using Saccharomyces
ellipsoideus in batch fermentation process was investigated. Effect of
five test variables in a defined range of inoculum concentration 6-
14% (v/v), pH (4.0-6.0), sugar concentration (14-22°Brix),
temperature (24-32°C) and time of incubation (30-54 hrs) on the
ethanol production were evaluated. Data obtained from experiment
were analyzed with RSM of MINITAB Software (Version 15)
whereby optimum ethanol concentration of 8.637% (v/v) was
determined. The optimum condition of 14% (v/v) inoculum
concentration, pH 6, 22°Brix, 26°C and 30hours of incubation. The
significant regression equation or model at the 5% level with
correlation value of 99.96% was also obtained.
Abstract: The main goal of this paper is to establish a
methodology for testing and optimizing GPRS performance over
Libya GSM network as well as to propose a suitable optimization
technique to improve performance. Some measurements of
download, upload, throughput, round-trip time, reliability, handover,
security enhancement and packet loss over a GPRS access network
were carried out. Measured values are compared to the theoretical
values that could be calculated beforehand. This data should be
processed and delivered by the server across the wireless network to
the client. The client on the fly takes those pieces of the data and
process immediately. Also, we illustrate the results by describing the
main parameters that affect the quality of service. Finally, Libya-s
two mobile operators, Libyana Mobile Phone and Al-Madar al-
Jadeed Company are selected as a case study to validate our
methodology.
Abstract: The paper proposes the novel design of a 3T XOR gate combining complementary CMOS with pass transistor logic. The design has been compared with earlier proposed 4T and 6T XOR gates and a significant improvement in silicon area and power-delay product has been obtained. An eight transistor full adder has been designed using the proposed three-transistor XOR gate and its performance has been investigated using 0.15um and 0.35um technologies. Compared to the earlier designed 10 transistor full adder, the proposed adder shows a significant improvement in silicon area and power delay product. The whole simulation has been carried out using HSPICE.
Abstract: Positron emission particle tracking (PEPT) is a
technique in which a single radioactive tracer particle can be
accurately tracked as it moves. A limitation of PET is that in order to
reconstruct a tomographic image it is necessary to acquire a large
volume of data (millions of events), so it is difficult to study rapidly
changing systems. By considering this fact, PEPT is a very fast
process compared with PET.
In PEPT detecting both photons defines a line and the annihilation
is assumed to have occurred somewhere along this line. The location
of the tracer can be determined to within a few mm from coincident
detection of a small number of pairs of back-to-back gamma rays and
using triangulation. This can be achieved many times per second and
the track of a moving particle can be reliably followed. This
technique was invented at the University of Birmingham [1].
The attempt in PEPT is not to form an image of the tracer particle
but simply to determine its location with time. If this tracer is
followed for a long enough period within a closed, circulating system
it explores all possible types of motion.
The application of PEPT to industrial process systems carried out
at the University of Birmingham is categorized in two subjects: the
behaviour of granular materials and viscous fluids. Granular
materials are processed in industry for example in the manufacture of
pharmaceuticals, ceramics, food, polymers and PEPT has been used
in a number of ways to study the behaviour of these systems [2].
PEPT allows the possibility of tracking a single particle within the
bed [3]. Also PEPT has been used for studying systems such as: fluid
flow, viscous fluids in mixers [4], using a neutrally-buoyant tracer
particle [5].
Abstract: In a bi-fuel diesel engine, the carburetor plays a vital
role in switching from fuel gas to petrol mode operation and viceversa.
The carburetor is the most important part of the fuel system of
a diesel engine. All diesel engines carry variable venturi mixer
carburetors. The basic operation of the carburetor mainly depends on
the restriction barrel called the venturi. When air flows through the
venturi, its speed increases and its pressure decreases. The main
challenge focuses on designing a mixing device which mixes the
supplied gas is the incoming air at an optimum ratio. In order to
surmount the identified problems, the way fuel gas and air flow in
the mixer have to be analyzed. In this case, the Computational Fluid
Dynamics or CFD approach is applied in design of the prototype
mixer. The present work is aimed at further understanding of the air
and fuel flow structure by performing CFD studies using a software
code. In this study for mixing air and gas in the condition that has
been mentioned in continuance, some mixers have been designed.
Then using of computational fluid dynamics, the optimum mixer has
been selected. The results indicated that mixer with 12 holes can
produce a homogenous mixture than those of 8-holes and 6-holes
mixer. Also the result showed that if inlet convergency was smoother
than outlet divergency, the mixture get more homogenous, the reason
of that is in increasing turbulence in outlet divergency.