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ARPN Journal of Engineering and
Applied Sciences
July 2021 | Vol. 16 No. 14 |
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Title: |
A meta-analysis of experiments on hydraulic properties of porous
pavements |
Author (s): |
Francesco Abbondati |
Abstract: |
A meta-analysis of studies evaluating the effect of porous pavements on
surface hydrology. The analysis investigated experiments on infiltration
rate and consequent runoff coefficient of porous pavements. Reviewed
literature provided extensive indications on the benefits of porous
pavements in mitigating hydrology in the built environment. It was
demonstrated that previous pavements improved the hydrological
properties of engineered surfaces including mitigating runoff and
checking to flood. Accordingly, it was hypothesised that the mean effect
among the selected studies is zero. A meta-analysis of selected
experiments on porous pavements experiments established that the mean
effect among the selected studies was zero. While the study adopted a
methodology that included similar studies in terms of method, further
study is recommended to control for the various factors that influence
hydraulic properties of porous pavers mentioned in the conclusion of
this study. |
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Title: |
Stress concentration in reinforced concrete connections subjected to
blast loads |
Author (s): |
Alireza Bahrami and Sina Matinrad |
Abstract: |
Investigating the stress concentration in reinforced concrete
connections under the blast loads is the purpose of the present paper.
This goal was achieved by the design and analysis of the connections.
The finite element package ABAQUS was used in this study to model and
analyse the connections. A reinforced concrete connection which was
tested experimentally was modelled and analysed in order to verify the
modelling. The results of the modelling and experimental test were
compared which demonstrated the accuracy of the modelling. Afterwards,
two reinforced concrete buildings with five and nine storeys were
designed employing the ETABS software. A beam-column connection of the
ground floor of each building was designed. The sizes of the
cross-sections of the beams and columns and the spaces of their stirrups
were considered differently. These connections were also modelled and
analysed. The distances of the connections from the blast centre were
considered as 2.5 m, 5 m, and 10 m and the blast powers were adopted as
500 kg, 1000 kg, and 2000 kg TNT equivalent mass of explosive for the
analyses of the connections. The stresses created in the reinforcements
of the connections owing to the blast loads were examined. It was
demonstrated that as the connection was located farther from the blast
centre, the stresses in the connection reinforcements were reduced.
Also, the stresses in the connection reinforcements were increased by
enhancing the blast power. Meanwhile, using larger cross-sections for
the beam and column in the connection of nine-storey building than the
connection of five-storey building transferred the stress concentration
in the reinforcements to the beam and near the beam-column connection.
By decreasing the stirrups spaces of the beam in the connection of
five-storey building, the high stresses in the reinforcements were
mainly transferred to the beam of the connection which could reduce the
likelihood of the progressive collapse of the structure. |
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Title: |
Modeling, control design and simulation of grid connected single-phase
solar micro inverter |
Author (s): |
Naseer Ahmad, Ahmad Hussain Safder and Mahmood Kassas |
Abstract: |
This paper represents the mathematical modeling, control design and
simulation of grid connected single phase solar micro inverter. A system
level approach is exploited to establish an upper-level block diagram
that depicts the various blocks of the solar inverter. These blocks are
PV panel, boost converter, inverter, ac grid and control system along
with their coordination in power and signal flow. In mathematics
modeling, complete state space model is developed, having three states
of the system, magnetizing current, output voltage current and voltage.
Photovoltaic voltage and duty ratio is taken as input to the state space
model. A transfer function model between output ac voltage and input
duty ratio is established and time domain analysis is conducted for its
stability analysis. Frequency domain analysis is also carried out and a
PI controller is designed to improve it relative stability. Feedback
compensator and feed forward loop both are used to improve the system
performance. The complete model along with its controller is developed
in Simulink. Results of the model reveal the accurate operation of the
inverter. DC rail output of the fly back converter produces 350V in
steady state. In the startup phase of the inverter, it took 0.03 sec to
synchronize the inverter output to the grid voltage. The peak voltage of
the inverter is kept high than the grid voltage for the power injection
to the grid. Safe mode operation of the inverter is tested by removing
the grid intentionally and the inverter output voltage become zero. |
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Title: |
Microwave dielectric analysis of thermal degradation on vegetable oils |
Author (s): |
Tan W. H., Cheng E. M., Lim E. A. and Tan W. C. |
Abstract: |
This study applied the measurement of dielectric properties and
reflection coefficient by using Agilent E8362B slim probe. Slim probe
and open-ended coaxial sensor are implemented to measure the dielectric
properties and reflection coefficient of the cooking oil samples. The
vegetable oils were purchased from the local market and were heated in
the oven. Five types of cooking oil are corn oil, olive oil, palm oil;
sunflower oil and walnut oil were measured at the temperature of 60°C,
80°C and 100°C for the frequency range of 0.2 GHz to 20GHz. As the oil,
undergoes thermal degradation during heating, the chemical chain of oil
will be altered and resulting in physical and internal properties
change. Dielectric properties are part of physical-chemical properties
of cooking oil that can be measured to inspect the oil quality.
According to the dielectric properties and reflection coefficient
measurement, there are different noticeable signal pattern which
indicates the used and fresh cooking oil and the effect of heating
period. |
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Title: |
Selected area electron diffraction study of magnetron sputtered of
Co80Sm20 thin films deposited on zirconium underlayer |
Author (s): |
Erwin Amiruddin |
Abstract: |
The structure of Co80Sm20 thin films deposited on zirconium underlayer
and without zirconium underlayer using dc magnetron sputtering technique
was investigated based on selected area electron diffraction (SAED) in
Transmission Electron Microscopy (TEM). The use of zirconium underlayer
between magnetic thin film and Si (100) substrate increases the
coercivity of the film by about two times compared to that for the film
deposited directly on Si (100) substrate. The film deposited directly on
a Si (100) substrate shows a larger loop squareness compared to that for
the film deposited on zirconium underlayer. The high coercivity observed
in the films deposited on thicker (100 nm) zirconium underlayer is
discussed. X-Ray Diffraction (XRD) pattern shows no crystalline
diffraction peaks from any of the Co80Sm20 thin film deposited on
zirconium underlayer. Moreover, XRD result reveals preferred (10.0) and
(00.2) orientation. Electron diffraction patterns reveal diffused rings
for thicker zirconium undelayer. No diffraction peak from Co80Sm20 thin
film can be observed from these electron diffraction patterns. |
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Title: |
Biostimulation of microorganisms for the wastewater pretreatment from
palm oil processing |
Author (s): |
Carlos Zafra-Mejía, Hugo Rondón-Quintana and Saieth Chaves-Pabón |
Abstract: |
The vegetable oil refining generates significant amounts of wastewater,
which can be highly acidic, oily, and with significant organic matter
loads. The objective of this paper is to show the development of a
biocatalyst for the stimulation of native bacterial population in
wastewater grease traps of a physical palm oil refining industry. The
results suggest that BOD5 is the indicator parameter for evaluating the
biostimulation efficiency in the wastewater pretreatment system (grease
traps). On average, BOD5 removal efficiency is 21.4%. For the entire
treatment system, BOD5 concentration of the final discharge during the biostimulation period is 1.38 times lower compared to the non-biostimulation
period. The dynamic model developed to simulate the biostimulation
system shows the following adjustment statistics: R2 = 92.5%,
root-mean-square error = 164836 CFU and mean-absolute-percentage error =
13.3%. Dynamic simulation suggests that the growth and decay phases in
the amount of total heterotrophic bacteria end at 15 and 67 days after
the biocatalyst has been applied, respectively. Namely, the system
stabilization phase starts at 68 days. The cost-effectiveness ratio of
the biostimulation treatment system is 1.27 times lower compared to the
non-biostimulation treatment system (physicochemical). The average
annual economic savings with the biostimulation system is $12.5USD per
ppm of BOD5 removed. |
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Title: |
Classical and predictive control applied
to a DC/DC Watkins-Johnson converter |
Author (s): |
Leonardo Aldana-Ortiz, Santiago A.
Carvajal-Aroca and Diego F. Sendoya-Losada |
Abstract: |
In
this work, two controllers, a Proportional Integral (PI) and a
Model-based Predictive Controller (MPC), have been designed to regulate
a DC/DC Watkins-Johnson converter. First, the modeling and linearization
of the system was performed using a frequency response estimation
method. Then the PI controller was designed around a certain setpoint.
Next, an algorithm was designed according to the Extended Prediction
Self-Adaptive Control (EPSAC). Finally, the performance of the
controllers is evaluated for setpoint tracking and disturbance
rejection. |
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Title: |
The development of IoT Controlled Hybrid Power
Switching |
Author (s): |
Mohammad Izzat Syamil Mohd. Azahar, Adam Samsudin, Ezzatul Farhain Azmi,
Amar Faiz Zainal Abidin and Norhafizah Md Sarif |
Abstract: |
This paper discusses the development system of IoT Controlled Hybrid
Power Switching to provide consumer a system which allows them to manage
their hybrid electricity sources. The generations of electricity can be
produced by various of resources such as conventional and renewable
resources. The existing method of generating electricity through
renewable resources for instance a small scale of stand-alone solar
photovoltaic system or pico-hydropower system gives consumers the
ability to generate their own electricity source. In general, generated
electricity from the resources is able to store in energy storage
devices such as rechargeable lead-acid batteries. The main reason for
generating electricity from renewable resources is that to reduce
consumer dependence on depleting conventional resources at the same time
they can experience monthly electricity bills saving. Without wasting
the existed conventional resources, two different electricity generation
can be combined thus creating a hybrid power system. The system is
developed in order for consumers to consume both resources efficiently
without producing any energy waste. The objectives development of IoT
Controlled Hybrid Power Switching could help the consumer to manage both
their electricity generation and consumption more effectively thus able
to reduce their monthly electricity bills with more savings. This system
provides flexibility for consumer to choose their options on how to
consume electricity consumption. The available options are Auto-Mode and
Manual-Mode. Both options using different methods consuming generated
electricity. The Auto-Mode implementing an IoT element that provides
consumers the ability to control electricity consumption through the
Blynk application on smartphones. The switching between two sources is
based on the percentage level of battery voltage capacity. For the
Manual-Mode, the option gives the consumer the capability to control
switching between two sources based on the time set by the consumer.
Both options are able to deliver advantages to consumers in order to
manage their electricity consumption dynamically. |
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Title: |
NIS-Egypt mass scale up to one ton after the
redefinition of the mass
unit |
Author (s): |
Sayed A. Emira, Fouad M. Ebrahim and Alaaeldin A. Eltawil |
Abstract: |
The one kilogram is the SI base unit of mass. It has been redefined on
20 May 2019 using an invariable natural constant. However, dissemination
of the one kilogram still realizes through weighing traced to standard
masses. Nevertheless, the NMIs will need to review and adjust their
uncertainty budgets for measurements made after this date. This work
describes dissemination of the mass unit for sub-multiple and multiples
of the kg, reference masses and weighing design using for this
dissemination. The traceability to the International Prototype one
Kilogram is performed through, calibrating the one kilogram standard and
using calibration design for the other weights associated with
uncertainty calculation. |
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Title: |
Spatial distributed control system of temperature field:
Synthesis and
modeling |
Author (s): |
Yury Ilyushin and Olga Afanaseva |
Abstract: |
In modern conditions, glass and glass products are becoming more and more
demanded in various industries. At the same time, the industry makes
more and more stringent requirements for the quality of products. This
requirement forces glass manufacturers to improve production
technologies aimed at improving the quality and reducing the cost of
production. This research work is devoted to the sheet stack production
technology modernization through the development and implementation of a
high-precision distributed controller. The paper analyzes the existing
system, synthesizes a regulator and performs mathematical modeling of
the resulting system. This work can be useful both for the manufacturer
of the sheet stack, and for specialists in the field of mathematical and
computer modeling. |
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Title: |
Effects of entry conditions on channel flow
characteristics |
Author (s): |
Oyewola O. M., Singh P. M., Odele R. P. and Petinrin M. O. |
Abstract: |
There have been various studies on channel flow due to its relevance in
engineering applications, but the effects of the entry conditions on the
its flow characteristics have not be given much attention. This 2-D
numerical simulation studied how the initial velocity and tripping
devices at the entrance of a channel affect the mean flow structure. The
CFD analysis is based on the use of COMSOL Multiphysics. The turbulent
stresses in the RANS equation are closed using the k-? turbulence model.
Input parameters for the simulation are taken from experimental
conditions in the literature, with Reynolds number ranging from 18,700
to 600, 000. The CFD strategy flow without tripping is validated against
experimental results and a good agreement is achieved. The results show
that the skin friction factor for the flow without tripping for Reynolds
number 18,700 is 3.59x10-3. However, for the same Re, with tripping
devices covering 15%, 30%, 45%, and 60% of the channel height, the skin
friction factors are 3.68x10-3, 3.78x10-3, 3.82x10-3, and 3.98x10-3
respectively. Hence it has been shown the tripping devices placed at the
entry of a channel increase the skin friction coefficient by values
between 2% to 11% for the various conditions considered in this work. |
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Title: |
Building facade inspection: A system based
on automated data acquisition, machine learning, and deep learning image
classification methods |
Author (s): |
Gabriel B. Bouzan, Paulo F. P. C. Fazzioni,
Renata G. Faisca and Carlos A. P. Soares |
Abstract: |
Building facade inspection usually uses time-consuming, expensive data
collection processes, with a risk level above the desirable, mainly
because it is based on visual inspection. In this context, studies that
address the acquisition of automated data and the post-processing of
digital images have increasingly aroused researchers interest. In this
work, we developed a low-cost system for identifying and classifying
building facades pathologies formed by a drone for capturing
high-resolution images and a web application containing three
components: a) a set of machine learning and deep learning algorithms
for the pathologies classification; b) a dataset of façade pathologies;
c) an interface that allows an environment of interaction and selection
of information that contributes to the user's decision-making process.
To select the best method for identifying the type of pathology, we also
performed a comparative analysis of algorithms effectiveness that uses
decision trees, random forests, and convolutional neural networks. The
results contribute to improving inspection processes on buildings
facades and reducing costs and the risk of accidents. |
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Title: |
Evaluation of water quality in the
quebrada El Salado through the application of the Water Quality Index
(ICA-NSF) (Parroquia El Valle, Cantón Cuenca, Ecuador) |
Author (s): |
Jose Fabian Espinoza Sarmiento, Maria
Fernanda Uguña Rosas, Carlos Alberto Severiche Sierra, Irlena Patricia
Ahumada Villafañe, Jose Rafael Palacio Angulo, Ivan Darío Orjuela and
Jorge Mario Posada |
Abstract: |
The
physical, chemical and microbiological parameters of the water in the El
Salado stream were determined, taking into account nine parameters:
turbidity, dissolved oxygen, BOD5, pH, nitrates, phosphates, fecal
coliforms, total solids and temperature in order to compare with the
regulations, after which the Water Quality Index of the National
Sanitation Foundation (ICA - NSF) of the United States was calculated;
For this, four monitoring campaigns were carried out between the months
of February, March, April and May 2019; at four sampling points. The
results obtained show that the water quality is within the range of Bad
to Medium. |
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Title: |
Traker: Mobile application to track
COVID-19 In Jakarta Indonesia |
Author (s): |
Vincent Chandra, Febrio Evan Hartanto,
Harco Leslie Hendric Spits Warnars, Priati Assiroj, Sardjoeni Moedjiono,
Thang Nguyen Ngoc, Fariza Hanis Abdul Razak and Wan Adilah Wan Adnan |
Abstract: |
COVID-19 (corona virus disease 2019) a newly discovered virus that
infects humans and is categorized as a global pandemic. Including in
Indonesia, everyday case of COVID-19 increases and gets worse. In this
digital era, we always use mobile smartphones every day to do our
activities, that is why Traker choosesa mobile platform for development.
Traker is a mobile application to trace and record the activity of an
infected person, also to show any information about COVID-19 to the
community as we proposed in Jakarta city. Traker works both on Android
and iOS and Traker uses GPS method solution to track down the infected.
The proposed model was designed using Unified Modeling Language (UML)
such as a use case diagram for figure out the business process in the
systems whilst a class diagram was used to design the database model.
Android studio was used to implement the systems where each displayed
user interfaces as a print screen of the running prototype application. |
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Title: |
Permission-based security gaps in android
OS |
Author (s): |
Saqlain Abbas, Abdul Mateen, Saeed Ullah,
Rubina Adnan and Sahar Arshad |
Abstract: |
Currently, mobile phones are one of the essential necessities that have
everyday usage applications (apps). These are used for sending and
receiving emails, watching pictures and movies, navigation, and much
more. One of the most famous open-source mobile platforms is the Android
which is installed on 79% of all new mobile devices. For the increase in
usage of the Android operating system, security assurance of the user
data is very important factor. The permission mechanism, required by the
Android, requests for very sensitive permissions which are a matter of
concern in most of the cases, but the user has to accept it to avail app
installation. Now a day, researchers are focusing on the Android
modification that includes the development of user-enhanced privacy over
it. Many solutions are being proposed but with the flaw of reduced
potential resulting from its modification. So it is required to develop
such solutions where a user has the facility to review and edit
permissions before the installation of an app. This paper provides a
survey of permission-based security models and approaches for the
Android operating system. The study also reveals and highlights the
security issues of Android. |
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Title: |
Method for the analytical evaluation of
convolution integral |
Author (s): |
Maryam Akhozahieh, Osama Nashwan and
Nasser Abdellatif |
Abstract: |
The
convolution integral is a linear operation. Invoking the linearity
property, the superposition principle is applied in this paper to obtain
the convolution integral between two signals. The method depends on
dividing the two signals into several segments; each has a fixed
function and a finite or infinite width. Depending on the product of the
segments’ number of the first signal and that of the second signal, the
evaluation of the convolution integral is divided into several sectors.
Within each sector, one, two, or three integrals are needed to be
calculated. The number of the integrals and the limits for each one
depends on the width and the edge points of the two signals’ segments
involved in a particular sector. After calculating all integrals, the
superposition principle is applied to find the convolution integral for
a specific period. The unit step function can be applied to express the
convolution integral as a single expression. |
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