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ARPN Journal of Engineering and Applied
Sciences March 2010 | Vol. 5 No. 3 |
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Title: |
Investigations on self-compacted self-curing concrete using
limestone powder and clinkers |
Author (s): |
C. Selvamony,
M. S. Ravikumar, S. U. Kannan and S. Basil Gnanappa |
Abstract: |
Self- Compacting concrete is a
type of concrete that gets compacted under its self-weight.
It’s commonly abbreviated as SCC and defined as the concrete
which can placed and compacted into every corner of a
formwork; purely means of it’s self-weight by eliminating the
need of either external energy input from vibrators or any
type of compacting effort. Self compactability and stability
are susceptible to ternary effects of chemical and mineral
admixture type and their content. In this study, the effect of
replacing the cement, coarse aggregate and fine aggregate by
limestone powder (LP) with silica fume, quarry dust and
clinkers respectively and their combinations of various
proportions on the properties of SCC has been compared.
Fresh properties, flexural and compressive strengths and
water absorption properties of Concrete were determined. The
use of SF in Concrete significantly increased the dosage of
superplasticiser (SP). At the same constant SP dosage (0·8%)
and mineral additives content (30%), LP can better improve the
workability than that of control and fine aggregate mixtures
by (5 % to 45 %). However, the
results of this study suggest that certain QD, SF and LP
combinations can improve the workability of SCCs, more than QD,
SF and LP alone. LP can have a positive influence on the
mechanical performance at early strength development while SF
improved aggregate-matrix bond resulting from the formation of
a less porous transition zone in Concrete. SF can better
reducing effect on total water absorption while QD and LP will
not have the same effect, at 28 days. |
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Title: |
Localization
of faults on power transmission lines using traveling wave
theory (TWT) |
Author (s): |
B.
Ravindhranath Reddy, M. Vijay Kumar, M. Surya Kalavathi and P.
Rajini Kumar |
Abstract: |
Transmission lines are designed
to transfer electric power from source locations to
distribution networks. However, their lengths are exposed to
various faults. Protective relay and fault recorder systems,
based on fundamental power frequency signals, are installed to
isolate the faulty line and provide the fault position.
However, the error is high especially in transmission lines.
This work investigates the problem of fault localization using
travelling wave current signals obtained at a single-end of a
transmission line and/or at multi-ends of a transmission
network. |
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Title: |
Some
investigations in friction drilling AA6351 using high speed
steel tools |
Author (s): |
P. V.
Gopal Krishna, K. Kishore and V. V. Satyanarayana |
Abstract: |
Friction
drilling is a non traditional hole making process in which a
conical rotating tool is applied to penetrate into workpiece
and create the hole in a single step, without generating
chips. The process relies on the heat generated due to the
frictional force between tool and workpiece, to soften,
penetrate and deform the work material into a bushing shape.
The mechanical aspects of friction drilling are investigated
in this paper. Aluminum (AA6351) is taken as work material and
friction drilling is carried out by high speed steel conical
tool. Mathematical models are developed in this work for axial
thrust and torque. Proper experimental layout is designed and
Taguchi Method is applied to evaluate the performance of high
speed steel friction drill on AA6351 work piece of thickness
1mm. |
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Title: |
Effect of
mixture constituents on the laminar burning velocity of
LPG-Co2-air mixtures |
Author (s): |
Ajay Tripathi, H. Chandra and M. Agrawal |
Abstract: |
One of the
most attractive applications of Liquefied petroleum gas (LPG)
is its use in IC engines, particularly for automotive
applications, as it is known to be a clean source of energy.
Even though it is already being used in IC engines, the
fundamental combustion properties such as laminar burning
velocities, which is a physicochemical property of a fuel, is
still not very well established, which can act as a basic
input for engine modeling. The present work utilizes a few
standard methods of flame speed measurement known from the
literature to obtain the flame speed of LPG-air and LPG-air-diluent
mixtures as a function of air-fuel ratio and diluent
concentration. Variation of burning velocity obtained by two
different experimental techniques, that is, orifice burner and
cylindrical tube method for a mixture of LPG-air and diluent
mixtures at different air fuel ratios is quantified. CO2
is selected as a diluent to account for the presence of
exhaust gases in the fresh charge as a consequence of exhaust
gas recirculation. It was found that there is effect on
burning velocity with the variation of effects of diluents on
the burning velocities have been found to cause performance
problems for combustion appliances using these types of fuel
gases. |
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Title: |
Classification and identification of Telugu handwritten
characters extracted from palm leaves using decision tree
approach |
Author (s): |
Panyam
Narahari Sastry, Ramakrishnan Krishnan and Bhagavatula Venkata
Sanker Ram |
Abstract: |
Research in character
recognition is very popular for various application potentials
in banks, post offices, defense organizations, reading aid for
the blind, library automation, language processing and
multi-media design. Even though Epigraphical work dealing with
stone inscriptions have been analyzed, these have been done
largely manually and also on 2D traces. A large collection of
these are available in the classical Indian languages like
Sanskrit, Tamil, Pali etc as well as in more modern languages
like Telugu. These characters on the palm leaf have the
additional properties like depth, an added feature which can
be gainfully exploited in character recognition. In this
paper, we explore how these 3D features can be extracted and
how they can be used in the recognition and classification
process. This paper describes a system to identify and
classify Telugu (a south Indian language) characters extracted
from the palm leaves, using Decision Tree approach. The
decision tree is developed using SEE5 algorithm, which is an
improvement from the predecessor ID3 and C4.5 algorithm. The
identification accuracy obtained is 93.10% using this method.
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Title: |
Monte Carlo
simulation for radiation transport: collision density in a 1-D
slab |
Author (s): |
Z. U. Koreshi
and S. Siddiq |
Abstract: |
Monte Carlo (MC) simulation has
been abundantly used for simulation of radiation transport
(thermal, neutron, charged-particle etc) in matter. In thermal
radiation, for example, surface radiosities and subsequent
heat fluxes have been accurately determined in configurations
which are difficult for deterministic formulations. In this
paper, we consider estimation of the collision density in a
1-D slab and compare with the exact solution. The accuracy of
the simulation results is discussed and a Poisson distribution
is shown for the events in a random walk. The purpose of this
paper is to demonstrate the underlying simulation process for
a simple problem. |
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Title: |
Component
model-Based condition monitoring of a gas turbine |
Author (s): |
E. A.
Ogbonnaya, K. T. Johnson, H. U. Ugwu and C. U. Orji |
Abstract: |
In recent years, the
requirements for reliability of machines that perform
different technological processes and their faults diagnoses
have become much stricter on most plants. The individual
component models are used to generate the source or cause of
fault in the engines. The failure of these components poses a
great problem to the equipment manufacturers and owners. A
step to the reduction of the faults led to the execution of
this work using gas turbine engines as case studies. Component
parametric readings collected from a gas turbine engine on
industrial duty for power generation were used to enunciate
steps to solve the problem by simulating likely deterioration
in its component data. A computer program code in Visual Basic
was used to actualize the simulation. The results obtained
show that early detection of faults could help to avoid
catastrophic downtime. Also the research revealed that the
pressure drop across turbine should not exceed 11.4 bar for
optimum performance. |
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Title: |
Explicit
dynamic simulation of drop weight low velocity impact on carbon
fibrous composite panels |
Author (s): |
Umar Farooq
and Karl Gregory |
Abstract: |
Finite element computational
model was developed to simulate impact behaviour and predict
the failure response of carbon fibrous composite panels
subjected to low velocity drop-weight impact on the
partitioned area where an impactor of flat-nosed tip hits the
target. Critical damage regions under impactors’ tips are very
complicated phenomenon to study since internal load
re-distributes after impact and damage accumulates in
through-the-thickness plies. Transformation of mathematical
formulations into numerical model and writing modular code
also need extensive efforts and time. However, efficient way
of solving the problems using commercial software generated
simulations. For this work, commercially available software
ABAQUSTM was selected, which incorporates shell
elements and stacks of plies. The user Table option of the
software provides an extended amount of input data without
having to re-link the code that could be utilised for various
load cases. Model developing and simulation techniques
associated with the software usage are presented herein. The
developed models are capable to simulate impact phenomena of
various drop weights for parametric studies. The methodology
applied consists of computing in-plane stresses from the model
and using Trapezium rule to calculate transverse shear
stresses from the standard equilibrium equations. The method
is simple and efficient to predict equivalent 3-D transverse
shear stresses from a 2-D model. These predicted and
calculated stresses were used in failure theories to predict
possible failure modes. Some of the results from failure
threshold loads were selected and included in the form of
Tables, contour plots and graphs. |
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Title: |
Process
monitoring and control of machining operations |
Author (s): |
Uche R
and Ebieto C. E. |
Abstract: |
This paper presents process
monitoring and control of machining operations. In this work,
a cutting dynamometer mounted on the machine was used to
measure the cutting force, cutting speed and the power
consumed in the operation. The tool life was also calculated
using the Taylor’s equation. It was shown that when the
cutting tool lifetime elapse, the tool no long give a good cut
which imperatively indicates a deteriorating condition of tool
life and possible failure. |
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Title: |
Rapid
chloride permeability test for durability studies on glass fibre
reinforced concrete |
Author (s): |
Chandramouli K., Srinivasa Rao P., Seshadri Sekhar T., Pannirselvam
N. and Sravana P. |
Abstract: |
Corrosion of reinforcing steel
due to chloride ingress is one of the most common
environmental attacks that lead to the deterioration of
concrete structures. Corrosion related damage to concrete
structures is a major problem. This durability problem has
received widespread attention in recent years because of its
frequent occurrence and the associated high cost of repairs.
Chlorides penetrate crack-free concrete by a variety of
mechanisms: capillary absorption, hydrostatic pressure,
diffusion, and evaporative transport. Of these, diffusion is
predominant. Diffusion occurs when the concentration of
chloride on the outside of the concrete member is greater than
on the inside. This results in chloride ions moving through
the concrete to the level of the rebar. When this occurs in
combination with wetting and drying cycles and in the presence
of oxygen, conditions are right for reinforcement corrosion.
The rate of chloride ion ingress into concrete is primarily
dependent on the internal pore structure. The pore structure
in turn depends on other factors such as the mix design,
degree of hydration, curing conditions, use of supplementary
cementitious materials, and construction practices. Therefore,
wherever there is a potential risk of chloride-induced
corrosion, the concrete should be evaluated for chloride
permeability. Researchers all over the world are attempting to
develop high performance concretes by using fibres and other
admixtures in concrete upto certain proportions. In the view
of the global sustainable developments, it is imperative that
fibres like glass, carbon, aramid and polypropylene fibers
provide improvements in tensile strength. Research in GFRC
(Glass fibre reinforced concrete) resulted in the development
of an alkali resistance fibre (AR Glass fibres High
Dispersion) that provided improved long term durability. In
the present experimental investigation cylinders of 100mm x
150mm of M20 grade concrete were cast with varying percentage
of addition of 0.03%, 0.06% and 0.1% of glass fibre. The rapid
chloride permeability tests were conducted for a period of 90,
180, 365 and 720 days. The test results show that the addition
of glass fibres exhibit better performance. |
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Title: |
Stress-strain
behavior of Nano/micro thin film materials |
Author (s): |
Swaminadham
Midturi |
Abstract: |
Nano/micro size thin films are
being developed at present for various applications as
stretchable electronic displays, flexible and foldable solar
panels, body conformable smart electronic textiles and
fabrics, and other embedded sensor-actuator surfaces. This
paper describes the results from an experimental investigation
of elastic-plastic deformation behavior of nano/micro thick
conducting metal such as gold (Au) on a highly compliant,
biocompatible polymer such as polydimethylsiloxane (PDMS). Two
layer laminates were fabricated with various nano Au film on
micron scale PDMS substrate and tested using a micro-tensile
tester. Also, in-situ scanning electron microscope (SEM)
tests captured the digital images of Au film under static load
to explain the changes in grain structure of the gold film.
Stress-strain data for the gold film under large deformation
was extracted using a mechanics of material based model, and
changes in stiffness values of the Au film were determined.
The experimental results validated the Hall-Petch law
indicating that the material strength properties have inverse
relationship with grain size. Results indicated that the
metallic Au films sustained large deformation without rupture
and SEM studies indicated that at higher strain levels, grains
in the Au film experienced intra-granular fractures. |
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Title: |
Artificial neural network model for performance
evaluation of RC rectangular beams with externally bonded glass
fibre reinforced polymer reinforcement |
Author (s): |
N.
Pannirselvam, V. Nagaradjane, K. Chandramouli and M.
Ravindrakrishna |
Abstract: |
The effect of glass fibre
reinforced polymer laminates on the performance of reinforced
concrete rectangular beams having different internal steel
reinforcement ratios was investigated. The parameters of
investigation included yield load, ultimate load, yield
deflection, ultimate deflection, maximum crack width,
deflection ductility and energy ductility. Artificial Neural
Network model was generated to predict the performance
characteristics taking percentage of steel reinforcement,
thickness of glass fibre reinforced polymer and the type of
fibre used in glass fibre reinforced polymer as parameters. |
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