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.
Abstract: Fructo-oligosaccharides (FOS) are produced from
sucrose by Aureobasidium pullulans in yields between 40-60%
(w/w). To increase the amount of FOS it is necessary to remove the
small, non-prebiotic sugars, present. Two methods for producing
high-purity FOS have been developed: the use of microorganisms
able to consume small saccharides; and the use of continuous
chromatography to separate sugars: simulated moving bed (SMB). It
is herein proposed the combination of both methods. The aim of this
study is to optimize the composition of the fermentative broth (in
terms of salts and sugars) that will be further purified by SMB. A
yield of 0.63 gFOS.gSucrose^-1 was obtained with A. pullulans using low
amounts of salts in the initial fermentative broth. By removing the
small sugars, Saccharomyces cerevisiae and Zymomonas mobilis
increased the percentage of FOS from around 56.0% to 83% (w/w) in
average, losing only 10% (w/w) of FOS during the recovery process.
Abstract: At certain depths during large diameter displacement
pile driving, rebound well over 0.25 inches was experienced,
followed by a small permanent-set during each hammer blow. High
pile rebound (HPR) soils may stop the pile driving and results in a
limited pile capacity. In some cases, rebound leads to pile damage,
delaying the construction project, and the requiring foundations
redesign. HPR was evaluated at seven Florida sites, during driving of
square precast, prestressed concrete piles driven into saturated, fine
silty to clayey sands and sandy clays. Pile Driving Analyzer (PDA)
deflection versus time data recorded during installation, was used to
develop correlations between cone penetrometer (CPT) pore-water
pressures, pile displacements and rebound. At five sites where piles
experienced excessive HPR with minimal set, the pore pressure
yielded very high positive values of greater than 20 tsf. However, at
the site where the pile rebounded, followed by an acceptable
permanent-set, the measured pore pressure ranged between 5 and 20
tsf. The pore pressure exhibited values of less than 5 tsf at the site
where no rebound was noticed. In summary, direct correlations
between CPTu pore pressure and rebound were produced, allowing
identification of soils that produce HPR.
Abstract: Shortfall of electrical energy in Pakistan is a challenge
adversely affecting its industrial output and social growth. As
elsewhere, Pakistan derives its electrical energy from a number of
conventional sources. The exhaustion of petroleum and conventional
resources, the rising costs coupled with extremely adverse climatic
effects are taking its toll especially on the under-developed countries
like Pakistan. As alternate, renewable energy sources like hydropower,
solar, wind, even bio-energy and a mix of some or all of them
could provide a credible alternative to the conventional energy
resources that would not only be cleaner but sustainable as well. As a
model, solar energy-based power grid for the near future has been
attempted to offset the energy shortfalls as a mix with our existing
sustainable natural energy resources. An assessment of solar energy
potential for electricity generation is being presented for fulfilling the
energy demands with higher level of reliability and sustainability.
This model is based on the premise that solar energy potential of
Pakistan is not only reliable but also sustainable. This research
estimates the present & future approaching renewable energy
resource specially the impact of solar energy based power grid for
mitigating energy shortage in Pakistan.
Abstract: An existing RC building in Madinah is seismically
evaluated with and without infill wall. Four model systems have been
considered i.e. model I (no infill), model IIA (strut infill-update from
field test), model IIB (strut infill- ASCE/SEI 41) and model IIC (strut
infill-Soft storey- ASCE/SEI 41). Three dimensional pushover
analyses have been carried out using SAP2000 software
incorporating inelastic material behavior for concrete, steel and infill
walls. Infill wall has been modeled as equivalent strut according to
suggested equation matching field test measurements and to the
ASCE/SEI 41 equation. The effect of building modeling on the
performance point as well as capacity and demand spectra due to EQ
design spectrum function in Madinah area has been investigated. The
response modification factor (R) for the 5 story RC building is
evaluated from capacity and demand spectra (ATC-40) for the
studied models. The results are summarized and discussed.
Abstract: Early pre-code reinforced concrete structures present
undetermined resistance to earthquakes. This situation is particularly
unacceptable in the case of essential structures, such as healthcare
structures and pilgrims' houses. Amongst these, an existing old RC
building in Madinah city (KSA) is seismically evaluated with and
without infill wall and their dynamic characteristics are compared
with measured values in the field using ambient vibration
measurements (AVM). After updating the mathematical models for
this building with the experimental results, three dimensional
pushover analysis (Nonlinear static analysis) was carried out using
commercial structural analysis software incorporating inelastic
material properties for concrete, infill and steel. The purpose of this
analysis is to evaluate the expected performance of structural systems
by estimating, strength and deformation demands in design, and
comparing these demands to available capacities at the performance
levels of interest. The results summarized and discussed.
Abstract: Chemical Reaction Optimization (CRO) is an
optimization metaheuristic inspired by the nature of chemical
reactions as a natural process of transforming the substances from
unstable to stable states. Starting with some unstable molecules with
excessive energy, a sequence of interactions takes the set to a state of
minimum energy. Researchers reported successful application of the
algorithm in solving some engineering problems, like the quadratic
assignment problem, with superior performance when compared with
other optimization algorithms. We adapted this optimization
algorithm to the Printed Circuit Board Drilling Problem (PCBDP)
towards reducing the drilling time and hence improving the PCB
manufacturing throughput. Although the PCBDP can be viewed as
instance of the popular Traveling Salesman Problem (TSP), it has
some characteristics that would require special attention to the
transactions that explore the solution landscape. Experimental test
results using the standard CROToolBox are not promising for
practically sized problems, while it could find optimal solutions for
artificial problems and small benchmarks as a proof of concept.
Abstract: This paper investigates the activity of the rectus
femoris (RF) and biceps femoris (BF) in healthy subjects during salat
(prostration) and specific exercise (squat exercise) using
electromyography (EMG). A group of undergraduates aged between
19 to 25 years voluntarily participated in this study. The myoelectric
activity of the muscles were recorded and analyzed. The finding
indicated that there were contractions of the muscles during the salat
and exercise with almost same EMG’s level. From the result,
Wilcoxon’s Rank Sum test showed significant difference between
prostration and squat exercise (p
Abstract: This paper presents the development of a single-ended 38.5 kS/s 10-bit programmable reference SAR ADC which is realized in MIMOS’s 0.35 µm CMOS process. The design uses a resistive DAC, a dynamic comparator with pre-amplifier and a SAR digital logic to create 10 effective bits ADC. A programmable reference circuitry allows the ADC to operate with different input range from 0.6 V to 2.1 V. The ADC consumed less than 7.5 mW power with a 3 V supply.
Abstract: Recently, increasing the quality of experience (QoE) is
an important issue. Since performance degradation at cell edge
extremely reduces the QoE, several techniques are defined at
LTE/LTE-A standard to remove inter-cell interference (ICI). However,
the conventional techniques have disadvantage because there is a
trade-off between resource allocation and reliable communication.
The proposed scheme reduces the ICI more efficiently by using
channel state information (CSI) smartly. It is shown that the proposed
scheme can reduce the ICI with fewer resources.
Abstract: Karst term is the determiner of a variety of areas or
landforms and unique perspectives that have been formed in result of
the of the ingredients dissolution of rocks constituter by natural
waters. Shiraz area with an area of 5322km2 is located in the simple
folded belt in the southern part of Zagros Mountain of Fars, and is
surrounded with Limestone Mountains (Asmari formation). Shiraz
area is located in Calcareous areas. The infrastructure of this city is
lime and absorbing wells that the city can influence the Limestone
dissolution and those accelerate its rate and increase the cavitation
below the surface. Dasht-e Arjan is a graben, which has been created
as the result of activity of two normal faults in its east and west sides.
It is a complete sample of Karst plains (Polje) which has been created
with the help of tectonic forces (fault) and dissolution process of
water in Asmari limestone formation. It is located 60km. off south
west of Shiraz (on Kazeroon-Shiraz road). In 1971, UNESCO has
recognized this plain as a reserve of biosphere. It is considered as one
of the world’s most beautiful geological phenomena, so that most of
the world’s geologists are interested in visiting this place. The
purpose of this paper is to identify and introduce landscapes of Karst
features shiraz city and Dasht-e Arjan including Karst dissolution
features (Lapiez, Karst springs, dolines, caves, underground caves,
ponors, and Karst valleys), anticlines and synclines, and Arjan Lake.
Abstract: Cost of governance in Nigeria has become a challenge
to development and concern to practitioners and scholars alike in the
field of business and social science research. In the 2010 national
budget of NGN4.6 trillion or USD28.75billion for instance, only a
pantry sum of NGN1.8trillion or USD11.15billion was earmarked for
capital expenditure. Similarly, in 2013, out of a total national budget
of NGN4.92trillion or USD30.75billion, only the sum of
NGN1.50trllion or USD9.38billion was voted for capital expenditure.
Therefore, based on the data sourced from the Nigerian Office of
Statistics, Central bank of Nigeria Statistical Bulletin as well as from
the United Nations Development Programme, this study examined
the causes of high cost of governance in Nigeria. It found out that the
high cost of governance in the country is in the interest of the ruling
class, arising from their unethical behaviour – corrupt practices and
the poor management of public resources. As a result, the study
recommends the need to intensify the war against corruption and
mismanagement of public resources by government officials as
possible solution to overcome the high cost of governance in Nigeria.
This could be achieved by strengthening the constitutional powers of
the various anti-corruption agencies in the area of arrest, investigation
and prosecution of offenders without the interference of the executive
arm of government either at the local, state or federal level.
Abstract: This paper impart the design and testing of
Nanotechnology based sequential circuits using multiplexer
conservative QCA (MX-CQCA) logic gates, which is easily testable
using only two vectors. This method has great prospective in the
design of sequential circuits based on reversible conservative logic
gates and also smashes the sequential circuits implemented in
traditional gates in terms of testability. Reversible circuits are similar
to usual logic circuits except that they are built from reversible gates.
Designs of multiplexer conservative QCA logic based two vectors
testable double edge triggered (DET) sequential circuits in VHDL
language are also accessible here; it will also diminish intricacy in
testing side. Also other types of sequential circuits such as D, SR, JK
latches are designed using this MX-CQCA logic gate. The objective
behind the proposed design methodologies is to amalgamate
arithmetic and logic functional units optimizing key metrics such as
garbage outputs, delay, area and power. The projected MX-CQCA
gate outshines other reversible gates in terms of the intricacy, delay.
Abstract: Due to water shortage, application of saline water for
irrigation is an urgent in agriculture. In this study the effect of
calcium and potassium application as additive in saline root media for
reduce salinity adverse effects was investigated on tomato growth in
a hydroponic system with unequal distribution of salts in the root
media, which was divided in to two equal parts containing full
Johnson nutrient solution and 40 mMNaCl solution, alone or in
combination with KCl (6 mM), CaCl2 (4 mM), K+Ca (3+2 mM) or
half-strength Johnson nutrient solution. The root splits were
exchanged every 7 days. Results showed that addition of calcium,
calcium-potassium and nutrition elements equivalent to half the
concentration of Johnson formula to the saline-half of culture media
minimized the reduction in plant growth caused by NaCl, although
addition of potassium to culture media wasn’t effective. The greatest
concentration of sodium was observed at the shoot of treatments
which had smallest growth. According to the results of this study, in
case of dynamic and non-uniform distribution of salts in the root
media, by addition of additive to the saline solution, it would be
possible to use of saline water with no significant growth reduction.
Abstract: In this study the instability problem of a modified
Taylor-Couette flow between two vertical coaxial cylinders of radius
R1, R2 is considered. The modification is based on the wavy shape of
the inner cylinder surface, where inner cylinders with different
surface amplitude and wavelength are used. The study aims to
discover the effect of the inner surface geometry on the instability
phenomenon that undergoes Taylor-Couette flow. The study reveals
that the transition processes depends strongly on the amplitude and
wavelength of the inner cylinder surface and resulting in flow
instabilities that are strongly different from that encountered in the
case of the classical Taylor-Couette flow.
Abstract: Liposome plays an important role in medical and
pharmaceutical science as e.g. nano scale drug carriers. Liposomes
are vesicles of varying size consisting of a spherical lipid bilayer and
an aqueous inner compartment. Magnet-driven liposome used for the
targeted delivery of drugs to organs and tissues. These liposome
preparations contain encapsulated drug components and finely
dispersed magnetic particles.
Liposomes are vesicles of varying size consisting of a spherical
lipid bilayer and an aqueous inner compartment that are generated in
vitro. These are useful in terms of biocompatibility, biodegradability,
and low toxicity, and can control biodistribution by changing the size,
lipid composition, and physical characteristics. Furthermore,
liposomes can entrap both hydrophobic and hydrophilic drugs and are
able to continuously release the entrapped substrate, thus being useful
drug carriers. Magnetic liposomes (MLs) are phospholipid vesicles
that encapsulate magneticor paramagnetic nanoparticles. They are
applied as contrast agents for magnetic resonance imaging (MRI).
The biological synthesis of nanoparticles using plant extracts plays
an important role in the field of nanotechnology. Green-synthesized
magnetite nanoparticles-protein hybrid has been produced by treating
Iron (III) / Iron (II) chloride with the leaf extract of Datura inoxia.
The phytochemicals present in the leaf extracts act as a reducing as
well stabilizing agents preventing agglomeration, which include
flavonoids, phenolic compounds, cardiac glycosides, proteins and
sugars.
The magnetite nanoparticles-protein hybrid has been trapped
inside the aqueous core of the liposome prepared by reversed phase
evaporation (REV) method using oleic and linoleic acid which has
been shown to be driven under magnetic field confirming the
formation magnetic liposome (ML). Chemical characterization of
stealth magnetic liposome has been performed by breaking the
liposome and release of magnetic nanoparticles. The presence iron
has been confirmed by colour complex formation with KSCN and
UV-Vis study using spectrophotometer Cary 60, Agilent.
This magnet driven liposome using nanoparticles-protein hybrid
can be a smart vesicles for the targeted drug delivery.
Abstract: Over the last few decades, oilfield service rolling
equipment has significantly increased in weight, primarily because of
emissions regulations, which require larger/heavier engines, larger
cooling systems, and emissions after-treatment systems, in some
cases, etc. Larger engines cause more vibration and shock loads,
leading to failure of electronics and control systems.
If the vibrating frequency of the engine matches the system
frequency, high resonance is observed on structural parts and mounts.
One such existing automated control equipment system comprising
wire rope mounts used for mounting computers was designed
approximately 12 years ago. This includes the use of an industrialgrade
computer to control the system operation. The original
computer had a smaller, lighter enclosure. After a few years, a newer
computer version was introduced, which was 10 lbm heavier. Some
failures of internal computer parts have been documented for cases in
which the old mounts were used. Because of the added weight, there
is a possibility of having the two brackets impact each other under
off-road conditions, which causes a high shock input to the computer
parts. This added failure mode requires validating the existing mount
design to suit the new heavy-weight computer.
This paper discusses the modal finite element method (FEM)
analysis and experimental modal analysis conducted to study the
effects of vibration on the wire rope mounts and the computer. The
existing mount was modelled in ANSYS software, and resultant
mode shapes and frequencies were obtained. The experimental modal
analysis was conducted, and actual frequency responses were
observed and recorded.
Results clearly revealed that at resonance frequency, the brackets
were colliding and potentially causing damage to computer parts. To
solve this issue, spring mounts of different stiffness were modeled in
ANSYS software, and the resonant frequency was determined.
Increasing the stiffness of the system increased the resonant
frequency zone away from the frequency window at which the engine
showed heavy vibrations or resonance. After multiple iterations in
ANSYS software, the stiffness of the spring mount was finalized,
which was again experimentally validated.
Abstract: This paper provides a comparative study on the
performances of standard PID and adaptive PID controllers tested on
travel angle of a 3-Degree-of-Freedom (3-DOF) Quanser bench-top
helicopter. Quanser, a well-known manufacturer of educational
bench-top helicopter has developed Proportional Integration
Derivative (PID) controller with Linear Quadratic Regulator (LQR)
for all travel, pitch and yaw angle of the bench-top helicopter. The
performance of the PID controller is relatively good; however, its
performance could also be improved if the controller is combined
with adaptive element. The objective of this research is to design
adaptive PID controller and then compare the performances of the
adaptive PID with the standard PID. The controller design and test is
focused on travel angle control only. Adaptive method used in this
project is self-tuning controller, which controller’s parameters are
updated online. Two adaptive algorithms those are pole-placement
and deadbeat have been chosen as the method to achieve optimal
controller’s parameters. Performance comparisons have shown that
the adaptive (deadbeat) PID controller has produced more desirable
performance compared to standard PID and adaptive (poleplacement).
The adaptive (deadbeat) PID controller attained very fast
settling time (5 seconds) and very small percentage of overshoot (5%
to 7.5%) for 10° to 30° step change of travel angle.
Abstract: Nowadays, Photovoltaic-PV Farms/ Parks and large
PV-Smart Grid Interface Schemes are emerging and commonly
utilized in Renewable Energy distributed generation. However, PVhybrid-
Dc-Ac Schemes using interface power electronic converters
usually has negative impact on power quality and stabilization of
modern electrical network under load excursions and network fault
conditions in smart grid. Consequently, robust FACTS based
interface schemes are required to ensure efficient energy utilization
and stabilization of bus voltages as well as limiting switching/fault
onrush current condition. FACTS devices are also used in smart grid-
Battery Interface and Storage Schemes with PV-Battery Storage
hybrid systems as an elegant alternative to renewable energy
utilization with backup battery storage for electric utility energy and
demand side management to provide needed energy and power
capacity under heavy load conditions. The paper presents a robust
interface PV-Li-Ion Battery Storage Interface Scheme for
Distribution/Utilization Low Voltage Interface using FACTS
stabilization enhancement and dynamic maximum PV power tracking
controllers.
Digital simulation and validation of the proposed scheme is done
using MATLAB/Simulink software environment for Low Voltage-
Distribution/Utilization system feeding a hybrid Linear-Motorized
inrush and nonlinear type loads from a DC-AC Interface VSC-6-
pulse Inverter Fed from the PV Park/Farm with a back-up Li-Ion
Storage Battery.
Abstract: Software Architecture is the basic structure of
software that states the development and advancement of a software
system. Software architecture is also considered as a significant tool
for the construction of high quality software systems. A clean design
leads to the control, value and beauty of software resulting in its
longer life while a bad design is the cause of architectural erosion
where a software evolution completely fails. This paper discusses the
occurrence of software architecture erosion and presents a set of
methods for the detection, declaration and prevention of architecture
erosion. The causes and symptoms of architecture erosion are
observed with the examples of prescriptive and descriptive
architectures and the practices used to stop this erosion are also
discussed by considering different types of software erosion and their
affects. Consequently finding and devising the most suitable
approach for fighting software architecture erosion and in some way
reducing its affect is evaluated and tested on different scenarios.