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ARPN Journal of Engineering and Applied
Sciences
February 2014 | Vol. 9 No. 2 |
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Title: |
Nonlinear
finite element analysis of shallow reinforced concrete beams
using solid65 element |
Author (s): |
M. A. Musmar,
M. I. Rjoub and M. A. Abdel Hadi |
Abstract: |
Shallow reinforced concrete beams are widely
used in building design and construction of waffle and ribbed
slabs in Jordan and in many other countries. Previous
researches included experimental based testing that has been
widely used as a means to study the response of reinforced
concrete flexural elements. In this regard the use of finite
element analysis is gaining popularity as it is cost
effective. Thus this work aims to study the behavior of
shallow reinforced concrete beams when subjected to transverse
loading, in terms of the resulting distribution of stresses,
cracks and load deflection relationship, using finite element
analysis utilzing ANSYS software. Solid65 eight noded
isoparametric elements are used to model the concrete. The
behavior of concrete material in compression is elasto-plastic
work hardening model which is terminated at the onset of
crushing. Link180 element models the reinforcement; the
material model for the discrete steel reinforcement is linear
elastic prior to initial yield surface, beyond that it is
perfectly plastic. |
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Title: |
Estimating
traffic operations at multi-lane roundabouts: a case study |
Author (s): |
Orazio
Giuffrè, Anna Granà, Tullio Giuffrè and Roberta
Marino |
Abstract: |
This paper addresses
traffic modeling issues at urban multi-lane roundabouts where,
despite circulating vehicles have priority, negotiation of the
right-of-way can occur between antagonist traffic flows, as a
result of minor drivers’ failing to obey the nominal operating
rule (stop or yield control). Existing models for the
estimation of operational performances have the shortcoming of
not representing the interdependencies between entering and
circulating vehicles at multi-lane roundabouts. An analytical
capacity model derived from field observations was developed
for this kind of intersections in a previous study. The
complexity of the model lies in the difficulty of observing
the behavioral parameters which are needed to implement the
model. A procedure to get unknown behavioral parameters from
traffic surveys is here proposed. This concerns saturation
headways, often eluding direct observations due to rare
occurrences of traffic conditions in which they can be
observed. The unknown parameters were estimated through a
regression model using onfield data collected at a multi-lane
roundabout. The presence of data correlation within a cluster
of observations required the estimation of the regression
parameters through a generalized estimating equation model.
Results gave insight into the analysis of operations at
multi-lane roundabouts, containing evidence to support
assumptions made for the estimation of unobservable
parameters. |
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Title: |
Solving the
dynamic models of reactive packed distillation process using
difference formula approaches |
Author (s): |
Abdulwahab
GIWA |
Abstract: |
One of the complex processes
encountered in process industries is reactive distillation
because it involves the integration of both reaction and
separation in a single unit. The process becomes more complex
if the column used is a packed type because, in that case, its
dynamic models are combinations of both ordinary and partial
differential equations. Obtaining the appropriate method that
can reliably give the solutions of these complex dynamic
models is one of the challenges facing Process Engineers. It
has been discovered that difference formula approaches can be
applied to convert the partial differential models of the
process to ordinary differential model types so that the
overall resulting ordinary differential dynamic models of the
process can be solved with the aid of ode command of
MATLAB. Therefore, this work has been carried out to
demonstrate how backward, forward and central difference
formula approaches involving two data points are applied in
solving the dynamic models developed for the reactive packed
distillation column used for the production of ethyl acetate.
The results obtained from the solutions of the dynamic models
using the three different difference formula approaches were
compared to the measured ones to determine the reliability of
each of the approaches in solving the dynamic models of the
reactive packed distillation process and backward difference
formula approach was discovered to be the best because the
liquid ethyl acetate mole fraction and the top segment
temperature it gave were found to compare very well with the
measured values. |
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Title: |
Offline
handwritten devnagari digit recognition |
Author (s): |
Rajiv Kumar
and Kiran Kumar Ravulakollu |
Abstract: |
This paper presents a study on the performance
of transformed domain features in Devnagari digit recognition.
In this research the recognition performance is measured from
features obtained in direct pixel value, Fourier Transform,
Discrete Cosine Transform, Gaussian Pyramid, Laplacian
Pyramid, Wavelet Transform and Curvelet Transform using
classification schemes: Feed Forward, Function Fitting,
Pattern Recognition, Cascade Neural Networks and K-nearest
Neighbor (K-NN). The Gaussian Pyramid based feature with KNN
classifier yielded the best accuracy of 96.93 % on the test
set. The recognition accuracy was increased to 98.02% by using
a majority voting classification scheme at expense of 0.26 %
rejection rate. The majority voting classifiers are based on
features: Gaussian pyramid, Laplacian pyramid, wavelet pyramid
and direct pixel value using KNN classifiers. |
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Title: |
Sign language
recognition: state of the art |
Author (s): |
Ashok K Sahoo
and Gouri Sankar Mishra |
Abstract: |
Sign language is used by deaf and hard hearing
people to exchange information between their own community and
with other people. Computer recognition of sign language deals
from sign gesture acquisition and continues till text/speech
generation. Sign gestures can be classified as static and
dynamic. However static gesture recognition is simpler than
dynamic gesture recognition but both recognition systems are
important to the human community. The sign language
recognition steps are described in this survey. The data
acquisition, data preprocessing and transformation, feature
extraction, classification and results obtained are examined.
Some future directions for research in this area also
suggested. |
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Title: |
Novel giant
magnetoresistance model using multiple barrier potential |
Author (s): |
Christian
Fredy Naa, Suprijadi, Sparisoma Viridi and Mitra Djamal |
Abstract: |
This paper proposes a new model for Giant
Magnetoresistance (GMR) and calculates its typical graph
qualitatively. The model’s foundation is the microscopic
mechanism in GMR, where the GMR effect can be explained by
intrinsic and extrinsic potential. The potentials are
spin-dependent. The potentials determine the transmission
probability then it will give conductance value. Here, the
multiple barrier potential model is proposed as the new GMR
model. The transmission probability is determined using
transfer matrix method. It was found that this model is fit
qualitatively with the typical GMR graph. |
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Title: |
Modeling the
stability of freestanding CNT probe/sensor in the vicinity of
graphene layers considering casimir dispersion force |
Author (s): |
Rouhollah Shokuhifard, Mojtaba Ojakeh, Ameneh Langari and Maryam K. Hafshejani |
Abstract: |
Carbon nanotube (CNT) is one the most important
nano-elements in fabrication of probes, sensors and other
ultra-small devices that have a wide usage in engineering and
medicine. In this paper, the deflection and instability of a
freestanding CNT probe/sensor in the vicinity of the graphene
layers are investigated. A nano-scale continuum model in
conjunction with Euler beam theory is employed to obtain
nonlinear constitutive equation of freestanding CNT by
considering the effect of Casimir dispersion force. A
numerical finite difference method is employed to solve the
nonlinear governing equation. |
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Title: |
Simulation of
air residence time distributions of spray droplets in a
counter-current spray dryer |
Author (s): |
Eyitayo A.
Afolabi and K.R Onifade |
Abstract: |
This research focused on the development of a
fundamental model that can be used to predict the air
residence time distribution of spray droplets in a
counter-current spray dryer. The proposed model consists of
two parallel sections. Firstly, two continuous stirred tanks
and a plug-flow in between and secondly, a plug-flow and a
stirred tank. A FORTRAN 77 program using Runge Kutta-Mersion
subroutine was used to simulate the three first order
differential and two linear model equations. The simulated
results showed that at high water and airflow rates, more
droplets enter into the mixing zones and large amount of
moisture content evaporated at a short time interval.
There
was good agreement between the experimental data and simulated
results airflow patterns which make it suitable for industrial
application and the standard deviations obtained are within
the acceptable limit. |
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Title: |
A reverse and
enhanced AODV routing protocol for manets |
Author (s): |
M. Sanabani,
R. Alsaqour and S. Kurkushi |
Abstract: |
Mobile Ad Hoc Network (MANET) is an autonomous
collection of mobile users that communicate over relatively
bandwidth constrained wireless links. Since the nodes are
mobile, the network topology may change rapidly and
unpredictably over time. The network is decentralized, where
all network activity including discovering the topology and
delivering packets must be executed by the nodes they, i.e.,
routing functionality will be incorporated into mobile nodes.
An Ad-hoc On-demand Distance Vector routing (AODV) is a
representative among the most widely studied on-demand ad hoc
routing protocols. Previous protocols have shown some
shortcomings on performance of AODV. AODV and most of the on
demand ad hoc routing protocols use single RREP along the
reverse path. Rapid change of topology causes that the RREP
could not arrive to the source node, i.e., after a source node
sends several RREQ packets; the node obtains a reply packet,
especially on high speed mobility. This increases both in
communication delay and power consumption as well as decrease
in packet delivery ratio. To avoid these problems, we proposed
a Reverse AODV (RAODV). RAODV tries multiple route replies
which reduces the path fail correction packets and obtains
better performance than other protocols. But RAODV has the
most control packet overhead. Therefore, in this paper, we
propose an Enhanced (EN-RAODV) that is improving the RAODV.
The performance is evaluated through NS-2 simulator.
Simulation results show that the proposed EN-RAODV improves
the performance of network comparing with RAODV and AODV in
most selected performance metrics such as packet delivery
ratio, end to end delay, throughput, routing packet sent and
routing overhead. |
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Title: |
The
association between client qualities and design team
attributes of green building projects |
Author (s): |
Mohamed S.
Abd. Elforgani, Abdahadi Alnawawi and Ismail Ben Rahmat |
Abstract: |
The construction industry has become more
complex due to changes in technology and the greater emphasis
placed on satisfying green requirements. The design phase is
the most important phase in determining the green performance
of building projects. The performance of the design team is
crucial. The selection of a design team should be based on a
set of criteria. Therefore, a competent design teams is
required to have a good understanding of environmental issues.
Design teams require a range of competences such as skills of
environmental assessments, initiatives and environmental
background as the basis for design decisions. In addition,
success of building projects greatly depends on the client’s
performance. The performance of clients is crucial since
decisions made will influence the overall project performance.
The quality of clients’ representatives has potential
influence on design team performance. In designing green
buildings client’s
attributes are critical factors to high performance of
building projects. The propose of this study to
identify the significant associations between variables of
design team attributes and client qualities. To achieve
mentioned aim a questionnaire survey was conducted to collect
dada required. A sample of 274 respondents has been covered
under the study, including architects and engineers practicing
design and consultancy building sectors. Prior to analysis of
data WINSTEPS software were used for Rasch modeling to
determine validity and reliability of date. Descriptive
analysis data includes quantitative and qualitative. The
results indicate that the influence of Clients’ Qualities on
Design Team Attributes is extensive. Coordination ability has
major influence on overall design team attributes. The higher
the Client Knowledge on Green buildings the higher is the
Design Team Attributes expected. |
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Title: |
A new
creativity tool to assist food processing equipment design |
Author (s): |
M.T. Barbier, F. Giroux, Y.
Coulibaly
and C. Marouzé |
Abstract: |
A knowledge-based tool was implemented in order
to assist in the design of food processing equipment. It was
developed and suggested for the use of professionals who are
seeking creative solutions for processing principles in a
given context and under specific constraints, especially in
the context of weak knowledge of food engineering and material
properties, poor economic conditions, and impossibility of
efficient use of existing design methodologies. This is
usually the case in many developing countries where equipment
supply is mostly limited to copies and adaptations of a few
models despite the big size of small scale food processing
sector, which results in the use of unsuitable equipment, lack
of efficiency, and bad quality. This new tool uses
knowledge-based methodology starting with the identification
of the most useful function (MUF) to be achieved in order to
identify the main product property change, hence leading to
the implementation of the targeted product. MUFs are linked to
scientific effects that can achieve them in order to suggest
designers a wide range of potential solutions. To facilitate
and orient access to useful knowledge for a given problem of
food processing principles, this tool is designed using a
database program and links to related and existing web-based
sites. Selection of optimal equipment types is finally carried
out by combining users’ manufacturing skills and
specifications in terms of cost, maintenance and current use
scheme. |
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Title: |
Energy
analysis of a CHP fuel cell system to
meet energy loads of a residential building |
Author (s): |
M.
Pourmahmoud, G. R. Ashari, M. Ojakeh and M. K. Hafshejani |
Abstract: |
This study deals with the energy analysis of a
polymer electrolyte membrane (PEM) fuel cell power system
including burner, steam reformer, heat exchanger and water
heater. This system has been considered to meet the
electrical, heating, cooling and domestic hot water loads of a
residential building located in Ahvaz. Natural gas is fuel of
the system and system works in CHP mode. The energy
requirements of residential building and the number of fuel
cell stacks to meet them have been estimated. The method
involved energy analysis and entropy generation through the
months of the year. Results show that all the energy needs of
the building can be met with 12 fuel cell stacks at a nominal
capacity of 8.5 kW. Energy analysis of the CHP system shows
that the increase in the ambient air temperature from 1oC
to 40oC, will have an increase of entropy
generation by 5.73%.Maximum entropy generates for 15 hour in
15th of June and 15th of July is estimated to
amount at 12624 (kW/K). Entropy generation of this system
through out a year is estimated to amount to 1004.54 GJ/k.year. |
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