Abstract: This paper presents a grid synchronization technique based on adaptive notch filter for SPV (Solar Photovoltaic) system along with MPPT (Maximum Power Point Tracking) techniques. An efficient grid synchronization technique offers proficient detection of various components of grid signal like phase and frequency. It also acts as a barrier for harmonics and other disturbances in grid signal. A reference phase signal synchronized with the grid voltage is provided by the grid synchronization technique to standardize the system with grid codes and power quality standards. Hence, grid synchronization unit plays important role for grid connected SPV systems. As the output of the PV array is fluctuating in nature with the meteorological parameters like irradiance, temperature, wind etc. In order to maintain a constant DC voltage at VSC (Voltage Source Converter) input, MPPT control is required to track the maximum power point from PV array. In this work, a variable step size P & O (Perturb and Observe) MPPT technique with DC/DC boost converter has been used at first stage of the system. This algorithm divides the dPpv/dVpv curve of PV panel into three separate zones i.e. zone 0, zone 1 and zone 2. A fine value of tracking step size is used in zone 0 while zone 1 and zone 2 requires a large value of step size in order to obtain a high tracking speed. Further, adaptive notch filter based control technique is proposed for VSC in PV generation system. Adaptive notch filter (ANF) approach is used to synchronize the interfaced PV system with grid to maintain the amplitude, phase and frequency parameters as well as power quality improvement. This technique offers the compensation of harmonics current and reactive power with both linear and nonlinear loads. To maintain constant DC link voltage a PI controller is also implemented and presented in this paper. The complete system has been designed, developed and simulated using SimPower System and Simulink toolbox of MATLAB. The performance analysis of three phase grid connected solar photovoltaic system has been carried out on the basis of various parameters like PV output power, PV voltage, PV current, DC link voltage, PCC (Point of Common Coupling) voltage, grid voltage, grid current, voltage source converter current, power supplied by the voltage source converter etc. The results obtained from the proposed system are found satisfactory.
Abstract: The world crude oil demand is projected to rise to 108.5 million bbl/d by the year 2035. With reserves estimated at 869 billion tonnes worldwide, coal remains an abundant resource. The aim of this work was to produce a high value hydrocarbon liquid product using a Direct Coal Liquefaction (DCL) process at, relatively mild operating conditions. Via hydrogenation, the temperature-staged approach was investigated in a dual reactor lab-scale pilot plant facility. The objectives included maximising thermal dissolution of the coal in the presence of tetralin as the hydrogen donor solvent in the first stage with 2:1 and 3:1 solvent: coal ratios. Subsequently, in the second stage, hydrogen saturation, in particular, hydrodesulphurization (HDS) performance was assessed. Two commercial hydrotreating catalysts were investigated viz. NickelMolybdenum (Ni-Mo) and Cobalt-Molybdenum (Co-Mo). GC-MS results identified 77 compounds and various functional groups present in the first and second stage liquid product. In the first stage 3:1 ratios and liquid product yields catalysed by magnetite were favoured. The second stage product distribution showed an increase in the BTX (Benzene, Toluene, Xylene) quality of the liquid product, branched chain alkanes and a reduction in the sulphur concentration. As an HDS performer and selectivity to the production of long and branched chain alkanes, Ni-Mo had an improved performance over Co-Mo. Co-Mo is selective to a higher concentration of cyclohexane. For 16 days on stream each, Ni-Mo had a higher activity than Co-Mo. The potential to cover the demand for low–sulphur, crude diesel and solvents from the production of high value hydrocarbon liquid in the said process, is thus demonstrated.
Abstract: The seriously damaged structures during earthquakes
show the need and importance of design of reinforced concrete
structures with high ductility. Reinforced concrete beam-column
joints have an important function in all structures. Under seismic
excitation, the beam column joint region is subjected to horizontal
and vertical shear forces whose magnitude is many times higher than
the adjacent beam and column. Strength and ductility of structures
depends mainly on proper detailing of the reinforcement in beamcolumn
joints and the old structures were found ductility deficient.
DSP materials are obtained by using high quantities of super
plasticizers and high volumes of micro silica. In the case of High
Performance Densified Small Particle Concrete (HPDSPC), since
concrete is dense even at the micro-structure level, tensile strain
would be much higher than that of the conventional SFRC, SIFCON
& SIMCON. This in turn will improve cracking behaviour, ductility
and energy absorption capacity of composites in addition to
durability. The fine fibers used in our mix are 0.3mm diameter and 10
mm which can be easily placed with high percentage. These fibers
easily transfer stresses and act as a composite concrete unit to take up
extremely high loads with high compressive strength. HPDSPC
placed in the beam column joints helps in safety of human life due to
prolonged failure.
Abstract: This paper presents the results of a Finite Element
based vibration analysis of a solar powered Unmanned Aerial
Vehicle (UAV). The purpose of this paper was to quantify the free
vibration, forced vibration response due to differing point inputs in
order to predict the relative response magnitudes and frequencies at
various wing locations of vibration induced power generators
(magnet in coil) excited by gust and/or control surface pulse-decays
used to help power the flight of the electric UAV. A Fluid Structure
Interaction (FSI) study was performed in order to ascertain pertinent
design stresses and deflections as well as aerodynamic parameters of
the UAV airfoil. The 10 ft span airfoil is modeled using Mylar as the
primary material. Results show that the free mode in bending is 4.8
Hz while the first forced bending mode is on range of 16.2 to 16.7 Hz
depending on the location of excitation. The free torsional bending
mode is 28.3 Hz, and the first forced torsional mode is range of 26.4
to 27.8 Hz, depending on the location of excitation. The FSI results
predict the coefficients of aerodynamic drag and lift of 0.0052 and
0.077, respectively, which matches hand-calculations used to validate
the Finite Element based results. FSI based maximum von Mises
stresses and deflections were found to be 0.282 MPa and 3.4 mm,
respectively. Dynamic pressures on the airfoil range from 1.04 to
1.23 kPa corresponding to velocity magnitudes in range of 22 to 66
m/s.
Abstract: During welding or flame cutting of metals, the
prediction of heat affected zone (HAZ) is critical. There is need to
develop a simple mathematical model to calculate the temperature
variation in HAZ and derivative analysis can be used for this purpose.
This study presents analytical solution for heat transfer through
conduction in mild steel plate. The homogeneous and nonhomogeneous
boundary conditions are single variables. The full field
analytical solutions of temperature measurement, subjected to local
heating source, are derived first by method of separation of variables
followed with the experimental visualization using infrared imaging.
Based on the present work, it is suggested that appropriate heat input
characteristics controls the temperature distribution in and around
HAZ.
Abstract: This study was undertaken at four different sites
(north polluted, south polluted, south healthy and north healthy) in
Tehran, in order to examine whether there was a relationship between
publicly available air quality data and the public’s perception of air
quality and to suggest some guidelines for reducing air pollution. A
total of 200 people were accidentally filled out the research
questionnaires at mentioned sites and air quality data were obtained
simultaneously from the Air Quality Control Department. Data was
analyzed in Excel and SPSS software’s. Clean air and job security
were of great importance to people comparing to other pleasant
aspect of life. Also air pollution and serious diseases were the most
important of people concerns. Street monitors and news paper
services on air quality were little used by the public as a means of
obtaining information on air pollution. Using public transportation
and avoiding inevitable journeys are the most important ways for
reducing air pollution. The results reveal that the public’s perception
of air quality is not a reliable indicator of the actual levels of air
pollution.
Abstract: The purpose of this paper is to examine the effects and
relationship of stress and social support towards the quality of life
among flood victims in Malaysia. A total of 764 respondents took
part in the survey via convenience sampling. The Depression,
Anxiety and Stress scale (DASS) was utilized to measure stress while
The Multidimensional Scale of Perceived Social Support was used to
measure social support. To measure quality of life, the combination
of WHO Quality of Life – BREF (WHOQOL-BREF) and The Impact
of Event Scale – Revised (IES-R) were utilized. The findings of this
study indicate that there were significant correlations between
variables in the study. The findings showed a significant negative
relation between stress and quality of life; and significant positive
correlations between support from family as well as support from
friends with quality of life. Stress and support from family were
found to be significant predictors that influence the quality of life
among flood victims.
Abstract: The purpose of this research was to investigate the
creep behaviour of the heterogeneous Timber-UHPFRC beams. New
developments have been done to further improve the structural
performance, such as strengthening of the timber (glulam) beam by
bonding composite material combine with an ultra-high performance
fibre reinforced concrete (UHPFRC) internally reinforced with or
without carbon fibre reinforced polymer (CFRP) bars. However, in
the design of wooden structures, in addition to the criteria of
strengthening and stiffness, deformability due to the creep of wood,
especially in horizontal elements, is also a design criterion. Glulam,
UHPFRC and CFRP may be an interesting composite mix to respond
to the issue of creep behaviour of composite structures made of
different materials with different rheological properties. In this paper,
we describe an experimental and analytical investigation of the creep
performance of the glulam-UHPFRC-CFRP beams assembled by
bonding. The experimental investigations creep behaviour was
conducted for different environments: in- and outside under constant
loading for approximately a year. The measured results are compared
with numerical ones obtained by an analytical model. This model was
developed to predict the creep response of the glulam-UHPFRCCFRP
beams based on the creep characteristics of the individual
components. The results show that heterogeneous glulam-UHPFRC
beams provide an improvement in both the strengthening and
stiffness, and can also effectively reduce the creep deflection of
wooden beams.
Abstract: This paper explores and provides substantiated
evidence on the usage patterns of Information and Communication
Technologies (ICTs) by female users at Vhembe District in Limpopo-
Province, South Africa. The study presents a comprehensive picture
on the usage of ICTs from female users’ perspective. The
significance of this study stems from the need to assess the role,
relevance and usage patterns of ICTs such as smartphones,
computers, laptops, and iPods, the internet and social networking
sites among females following the developments of new media
technologies in society. The objective of the study is to investigate
the usability and accessibility of ICTs to empower female users in
South Africa. The study used quantitative and qualitative research
methods to determine the major ideas, perceptions and usage patterns
of ICTs by users. Data collection involved the use of structured selfadministered
questionnaire from two groups of respondents who
participated in this study. Thus, (n=50) female students at the
University of Venda provided their ideas and perceptions about the
usefulness and usage patterns of ICTs such as smartphones, the
Internet and computers at the university level, whereas, the second
group were (n=50) learners from Makhado Comprehensive School
who provided their perceptions and ideas about the use of ICTs at the
high school level. The researcher also noted that the findings of the
study were useful as a guideline and model for ICT intervention that
could work as an empowerment to women in South Africa. It was
observed that the central purpose of ICTs among female users was to
search for information regarding assignment writing, conducting
research, dating, exchanging ideas and networking with friends and
relatives. This was demonstrated by a high number of females who
used ICTs for e-learning (62%) and social purposes (85%).
Therefore, the study revealed that most females used ICTs for social
purposes and accessing the internet rather than for entertainment, a
gesture that provides an opportune space to empower rural women in
South Africa.
Abstract: Networked environments which provide platforms for
business organizations are configured in different forms depending
on many factors including life time, member characteristics,
communication structure, and business objectives, among others.
With continuing advances in digital technologies the distance has
become a less barrier for business minded collaboration among
organizations. With the need and ease to make business collaborate
nowadays organizations are sometimes forced to co-work with others
that are either unknown or less known to them in terms of history and
performance. A promising approach for sustaining established
collaboration has been establishment of trust relationship among
organizations based on assessed trustworthiness for each participating
organization. It has been stated in research that trust in organization is
dynamic and thus assessment of trust level must address such
dynamic nature. This paper assesses relevant aspects of trust and
applies the assessed concepts to propose a semi-automated system for
the management of Sustainability and Evolution of trust in
organizations participating in specific objective in a networked
organizations environment.
Abstract: This paper presents an analytical approach for
evaluating distribution system reliability indices in the presence of
distributed generation. Modeling distributed generation and
evaluation of distribution system reliability indices using the
frequency duration technique. Using model implements and case
studies are discussed. Results showed that location of DG and its
effect in distribution reliability indices. In this respect, impact of DG
on distribution system is investigated using the IEEE Roy Billinton
test system (RBTS2) included feeder 1. Therefore, it will help to the
distribution system planners in the DG resource placement.
Abstract: Malaysia’s green building development is gaining
momentum and green buildings have become a key focus area,
especially within the commercial sector with the encouragement of
government legislation and policy. Due to the emerging awareness
among the market players’ views of the benefits associated with the
ownership of green buildings in Malaysia, there is a need for valuers
to incorporate consideration of sustainability into their assessments of
property market value to ensure the green buildings continue to
increase in the market. This paper analyses the valuers’ current
perception on the valuation practices with regard to the green issues
in Malaysia. The study was based on a survey of registered real estate
valuers and the experts whose work related to valuation in the Klang
Valley area to rate their view regarding the perception on valuation of
green building. The findings present evidence that even though
Malaysian valuers have limited knowledge of green buildings, they
recognise the importance of incorporating the green features in the
valuation process. The inclusion of incorporating the green features
in valuations in practice was hindered by the inadequacy of sufficient
transaction data in the market. Furthermore, valuers experienced
difficulty in identifying what are the various input parameters of
green building and how to adjust it in order to reflect the benefit of
sustainability features correctly in the valuation process. This paper
focuses on the present challenges confronted by Malaysian valuers
with regards to incorporating the green features in their valuation.
Abstract: MHD chemically reacting viscous fluid flow towards
a vertical surface with slip and convective boundary conditions has
been conducted. The temperature and the chemical species
concentration of the surface and the velocity of the external flow are
assumed to vary linearly with the distance from the vertical surface.
The governing differential equations are modeled and transformed
into systems of ordinary differential equations, which are then solved
numerically by a shooting method. The effects of various parameters
on the heat and mass transfer characteristics are discussed. Graphical
results are presented for the velocity, temperature, and concentration
profiles whilst the skin-friction coefficient and the rate of heat and
mass transfers near the surface are presented in tables and discussed.
The results revealed that increasing the strength of the magnetic field
increases the skin-friction coefficient and the rate of heat and mass
transfers toward the surface. The velocity profiles are increased
towards the surface due to the presence of the Lorenz force, which
attracts the fluid particles near the surface. The rate of chemical
reaction is seen to decrease the concentration boundary layer near the
surface due to the destructive chemical reaction occurring near the
surface.
Abstract: The effect of carbon nanofibers (CNFs) on the
electrical properties of Poly(vinylidene fluoride-hexafluoropropylene)
(P(VdF-HFP)) based gel polymer electrolytes has been investigated
in the present work. The length and diameter ranges of CNFs used in
the present work are 5-50 μm and 200-600 nm respectively. The
nanocomposite gel polymer electrolytes have been synthesized by
solution casting technique with varying CNFs content in terms of
weight percentage. Electrochemical impedance analysis demonstrates
that the reinforcement of carbon nanofibers significantly enhances the
ionic conductivity of the polymer electrolyte. The decrease of
crystallinity of P(VdF-HFP) due the addition of CNFs has been
confirmed by X-ray diffraction (XRD). The interaction of CNFs with
various constituents of nanocomposite gel polymer electrolytes has
been assessed by Fourier Transform Infrared (FTIR) spectroscopy.
Moreover CNFs added gel polymer electrolytes offer superior
thermal stability as compared to that of CNFs free electrolytes as
confirmed by Thermogravimetric analysis (TGA).
Abstract: This paper deals with the problem of management of
information resources in libraries of the public institution Sultan
Moulay Slimane University (SMSU) in order to analyze the
satisfaction of the readers, and allow university leaders to make better
strategic and instant decisions. For this, the integration of an
integrated management decision library system is a priority program
of higher education, as part of the Digital Morocco, which has a
proactive policy to develop the use of new technologies information
and communication in higher institutions. This operational
information system can provide better services to the students and for
the leaders. Our approach is to integrate the tools of business
intelligence (BI) in the library management by using power BI.
Abstract: Healthcare safety has been perceived important. It is
essential to prevent troubles in healthcare processes for healthcare
safety. Trouble prevention is based on trouble prediction using
accumulated knowledge on processes, troubles, and countermeasures.
However, information on troubles has not been accumulated in
hospitals in the appropriate structure, and it has not been utilized
effectively to prevent troubles. In the previous study, however a
detailed knowledge acquisition process for trouble prediction was
proposed, the knowledgebase for countermeasures was not involved.
In this paper, we aim to propose the structure of the knowledgebase for
countermeasures, in the knowledge acquisition process for trouble
prediction in healthcare process. We first design the structure of
countermeasures and propose the knowledge representation form on
countermeasures. Then, we evaluate the validity of the proposal, by
applying it into an actual hospital.
Abstract: The current study aims to highlight the loading
characteristics impact on the time evolution (focusing particularly on
long term effects) of the deformation of realized reinforced concrete
beams. Namely the tension stiffening code provisions (i.e. within
Eurocode 2) are reviewed with a clear intention to reassess their
operational value and predicting capacity. In what follows the
experimental programme adopted along with some preliminary
findings and numerical modeling attempts are presented. For a range of long slender reinforced concrete simply supported
beams (4200 mm) constant static sustained and repeated cyclic
loadings were applied mapping the time evolution of deformation.
All experiments were carried out at the Heavy Structures Lab of the
University of Leeds. During tests the mid-span deflection, creep
coefficient and shrinkage strains were monitored for duration of 90
days. The obtained results are set against the values predicted by
Eurocode 2 and the tools within an FE commercial package (i.e.
Midas FEA) to yield that existing knowledge and practise is at times
over-conservative.
Abstract: Tamil handwritten document is taken as a key source
of data to identify the writer. Tamil is a classical language which has
247 characters include compound characters, consonants, vowels and
special character. Most characters of Tamil are multifaceted in
nature. Handwriting is a unique feature of an individual. Writer may
change their handwritings according to their frame of mind and this
place a risky challenge in identifying the writer. A new
discriminative model with pooled features of handwriting is proposed
and implemented using support vector machine. It has been reported
on 100% of prediction accuracy by RBF and polynomial kernel based
classification model.
Abstract: A sliding door system is used in commercial vehicles
and passenger cars to allow a larger unobstructed access to the
interior for loading and unloading. The movement of a sliding door
on vehicle body is ensured by mechanisms and tracks having special
cross-section which is manufactured by roll forming and stretch
bending process. There are three tracks and three mechanisms which
are called upper, central and lower on a sliding door system. There
are static requirements as strength on different directions, rigidity for
mechanisms, door drop off, door sag; dynamic requirements as high
energy slam opening-closing and durability requirement to validate
these products. In addition, there is a kinematic requirement to find
out force values from door handle during manual operating. In this
study, finite element analysis and physical test results which are
realized for sliding door systems will be shared comparatively.
Abstract: Hollow section for bridge columns has some
advantages. However, current seismic design codes do not provide
design regulations for hollow bridge piers. There have been many
experimental studied for hollow reinforced concrete piers in the world.
But, Study for hollow section for bridge piers in Korea has been begun
with approximately 2000s. There has been conducted experimental
study for hollow piers of flexural controlled sections by Yeungnam
University, Sung kyunkwan University, Korea Expressway
Corporation in 2009. This study concluded that flexural controlled
sections for hollow piers showed the similar behavior to solid sections.
And there have been conducted experimental study for hollow piers of
compression controlled sections by Yeungnam University, Korea
Institute of Construction Technology in 2012. This study concluded
that compression controlled sections for hollow piers showed
compression fracture of concrete in inside wall face. Samsung
Construction & Trading Corporation has been conducted study with
Yeungnam University for reduce the quantity of reinforcement details
about hollow piers. Reduce the quantity of reinforcement details are
triangular cross tie. This study concluded that triangular reinforcement
details showed the similar behavior as compared with existing
reinforcement details.