Abstract: This paper presents the design analysis of saddle
support of a horizontal pressure vessel. Since saddle have the vital
role to support the pressure vessel and to maintain its stability, it
should be designed in such a way that it can afford the vessel load
and internal pressure of the vessel due to liquid contained in the
vessel. A model of horizontal pressure vessel and saddle support is
created in ANSYS. Stresses are calculated using mathematical
approach and ANSYS software. The analysis reveals the zone of high
localized stress at the junction part of the pressure vessel and saddle
support due to operating conditions. The results obtained by both the
methods are compared with allowable stress value for safe designing.
Abstract: Most quality models have defined usability as a
significant factor that leads to improving product acceptability,
increasing user satisfaction, improving product reliability, and also
financially benefitting companies. Usability is also the best factor that
balances both the technical and human aspects of a software product,
which is an important aspect in defining quality during software
development process. A usability risk consist risk factors that could
impact the usability of a software product thereby contributing to
negative user experiences and causing a possible software product
failure. Hence, it is important to mitigate and reduce usability risks in
the software development process itself. By managing possible
usability risks in software development process, failure of software
product could be reduced. Therefore, this research uses the Delphi
method to identify mitigation plans for reducing potential usability
risks. The Delphi method is conducted with seven experts from the
field of risk management and software development.
Abstract: There are several methods to monitor software
projects and the objective for monitoring is to ensure that the
software projects are developed and delivered successfully. A
performance measurement is a method that is closely associated with
monitoring and it can be scrutinized by looking at two important
attributes which are efficiency and effectiveness both of which are
factors that are important for the success of a software project.
Consequently, a successful steering is achieved by monitoring and
controlling a software project via the performance measurement
criteria and metrics. Hence, this paper is aimed at identifying the
performance measurement criteria and the metrics for monitoring the
performance of a software project by using the Goal Question
Metrics (GQM) approach. The GQM approach is utilized to ensure
that the identified metrics are reliable and useful. These identified
metrics are useful guidelines for project managers to monitor the
performance of their software projects.
Abstract: Climate change will affect various aspects of
hydrological cycle such as rainfall. A change in rainfall will affect
flood magnitude and frequency in future which will affect the design
and operation of hydraulic structures. In this paper, trends in subhourly,
sub-daily, and daily extreme rainfall events from 18 rainfall
stations located in Tasmania, Australia are examined. Two nonparametric
tests (Mann-Kendall and Spearman’s Rho) are applied to
detect trends at 10%, 5%, and 1% significance levels. Sub-hourly (6,
12, 18, and 30 minutes) annual maximum rainfall events have been
found to experience statistically significant upward trends at 10%
level of significance. However, sub-daily durations (1 hour, 3 and 12
hours) exhibit decreasing trends and no trends exists for longer
duration rainfall events (e.g. 24 and 72 hours). Some of the durations
(e.g. 6 minutes and 6 hours) show similar results (with upward
trends) for both the tests. For 12, 18, 60 minutes and 3 hours
durations both the tests show similar downward trends. This finding
has important implication for Tasmania in the design of urban
infrastructure where shorter duration rainfall events are more relevant
for smaller urban catchments such as parking lots, roof catchments
and smaller sub-divisions.
Abstract: The global solved problem is the calculation of the
parameters of ceramic material from a set of destruction tests of
ceramic heads of total hip joint endoprosthesis. The standard way of
calculation of the material parameters consists in carrying out a set of
3 or 4 point bending tests of specimens cut out from parts of the
ceramic material to be analysed. In case of ceramic heads, it is not
possible to cut out specimens of required dimensions because the
heads are too small (if the cut out specimens were smaller than the
normalised ones, the material parameters derived from them would
exhibit higher strength values than those which the given ceramic
material really has). A special destruction device for heads
destruction was designed and the solved local problem is the
modification of this destructive device based on the analysis of
tensile stress in the head for two different values of the depth of the
conical hole in the head. The goal of device modification is a shift of
the location with extreme value of σ1max from the region of head’s
hole bottom to its opening. This modification will increase the
credibility of the obtained material properties of bioceramics, which
will be determined from a set of head destructions using the Weibull
weakest link theory.
Abstract: In this paper two approaches to joint signal detection,
time of arrival (ToA) and angle of arrival (AoA) estimation in
multi-element antenna array are investigated. Two scenarios were
considered: first one, when the waveform of the useful signal
is known a priori and, second one, when the waveform of the
desired signal is unknown. For first scenario, the antenna array
signal processing based on multi-element matched filtering (MF)
with the following non-coherent detection scheme and maximum
likelihood (ML) parameter estimation blocks is exploited. For second
scenario, the signal processing based on the antenna array elements
covariance matrix estimation with the following eigenvector analysis
and ML parameter estimation blocks is applied. The performance
characteristics of both signal processing schemes are thoroughly
investigated and compared for different useful signals and noise
parameters.
Abstract: A study was conducted to determine the diversity and
abundance of shorebird species habituating the mudflat area of Jeram
Beach and Remis Beach, Selangor, Peninsular Malaysia. Direct
observation technique (using binoculars and video camera) was
applied to record the presence of bird species in the sampling sites
from August 2013 until July 2014. A total of 32 species of shorebird
were recorded during both migratory and non-migratory seasons. Of
these, eleven species (48%) are migrants, six species (26%) have both
migrant and resident populations, four species (17%) are vagrants and
two species (9%) are residents. The compositions of the birds
differed significantly in all months (χ2 = 84.35, p < 0.001). There is a
significant difference in avian abundance between migratory and
non-migratory seasons (Mann-Whitney, t = 2.39, p = 0.036). The
avian abundance were differed significantly in Jeram and Remis
Beaches during migratory periods (t = 4.39, p = 0.001) but not during
non-migratory periods (t = 0.78, p = 0.456). Shorebird diversity was
also affected by tidal cycle. There is a significance difference
between high tide and low tide (Mann-Whitney, t = 78.0, p < 0.005).
Frequency of disturbance also affected the shorebird distribution
(Mann-Whitney, t = 57.0, p = 0.0134). Therefore, this study
concluded that tides and disturbances are two factors that affecting
temporal distribution of shorebird in mudflats area.
Abstract: Hot aqueous and methanol extracts of the two selected
herbal medicines such are Vellarugu chooranam (V.C) and
Amukkirai Chooranam (A.C) were examined for total phenolic and
flavonoid contents and in vitro antioxidant activity using four
different methods. The total phenolic and flavonoid contents in
methanol extract of V.C were found to be higher (44.41±1.26mg
GAE/g; 174.44±9.32mg QE/g) than in the methanol extract of A.C
(20.56±0.67mg GAE/g; 7.21±0.85mg QE/g). Hot methanol and
aqueous extracts of both medicines showed low antioxidant activity
in DPPH, ABTS, and FRAP methods and Iron chelating activity not
found at highest possible concentration. V.C contains higher
concentrations of total phenolic and flavonoid contents than A.C and
can also exert greater antioxidant activity than A.C, although the
activities demonstrated were lower than the positive control Trolox.
The in vitro antioxidant activity was not related with the total
phenolic and flavonoid contents of the methanol and aqueous extracts
of both herbal medicines (A.C and V.C).
Abstract: Nonstandard tests are necessary for analyses and
verification of new developed structural and technological solutions
with application of composite materials. One of the most critical
primary structural parts of a typical aerospace structure is T-joint.
This structural element is loaded mainly in shear, bending, peel and
tension. The paper is focused on the shear loading simulations. The
aim of the work is to obtain a representative uniform distribution of
shear loads along T-joint during the mechanical testing. A new
design of T-joint test procedure, numerical simulation and
optimization of representative boundary conditions are presented.
The different conditions and inaccuracies both in simulations and
experiments are discussed. The influence of different parameters on
stress and strain distributions is demonstrated on T-joint made of
CFRP (carbon fibre reinforced plastic). A special test rig designed by
VZLU (Aerospace Research and Test Establishment) for T-shear test
procedure is presented.
Abstract: In this paper the effect of wall waviness of side walls
in a two-dimensional wavy enclosure is numerically investigated.
Two vertical wavy walls and straight top wall are kept isothermal and
the bottom wall temperature is higher and spatially varying with
cosinusoidal temperature distribution. A computational code based on
Finite-volume approach is used to solve governing equations and
SIMPLE method is used for pressure velocity coupling. Test is
performed for several different numbers of undulations. The Prandtl
number was kept constant and the Ra number denotes that the flow is
laminar. Temperature and velocity fields are determined. Therefore,
according to the obtained results a correlation is proposed for average
Nusselt number as a function of number of side wall waves. The
results indicate that the Nusselt number is highly affected by number
of waves and increasing it decreases the wavy walls Nusselt number;
although the Nusselt number is not highly affected by surface
waviness when the number of undulations is below one.
Abstract: In this paper, we present a comparative assessment of
Space Vector Pulse Width Modulation (SVPWM) and Model
Predictive Control (MPC) for two-level three phase (2L-3P) Voltage
Source Inverter (VSI). VSI with associated system is subjected to
both control techniques and the results are compared.
Matlab/Simulink was used to model, simulate and validate the
control schemes. Findings of this study show that MPC is superior to
SVPWM in terms of total harmonic distortion (THD) and
implementation.
Abstract: This article presents summary on preparation and
characterization of zinc, copper, cadmium and cobalt chromite
nanocrystals, embedded in an amorphous silica matrix. The
ZnCr2O4/SiO2, CuCr2O4/SiO2, CdCr2O4/SiO2 and CoCr2O4/SiO2
nanocomposites were prepared by a conventional sol-gel method
under acid catalysis. Final heat treatment of the samples was carried
out at temperatures in the range of 900−1200 ◦C to adjust the
phase composition and the crystallite size, respectively. The resulting
samples were characterized by Powder X-ray diffraction (PXRD),
High Resolution Transmission Electron Microscopy (HRTEM),
Raman/FTIR spectroscopy and magnetic measurements. Formation
of the spinel phase was confirmed in all samples. The average size of
the nanocrystals was determined from the PXRD data and by direct
particle size observation on HRTEM; both results were correlated.
The mean particle size (reviewed by HRTEM) was in the range from
∼4 to 46 nm. The results showed that the sol-gel method can be
effectively used for preparation of the spinel chromite nanoparticles
embedded in the silica matrix and the particle size is driven by the
type of the cation A2+ in the spinel structure and the temperature
of the final heat treatment. Magnetic properties of the nanocrystals
were found to be just moderately modified in comparison to the bulk
phases.
Abstract: Artemisia species, which are medically beneficial, are
widespread in temperate regions of both Northern and Southern
hemispheres among which Iran is located. About 35 species of
Artemisia are indigenous in Iran among them some are widespread in
all or most provinces, yet some are restricted to some specific
regions. In this review paper, initially, GC-Mass results of some
experiments done in different provinces of Iran are mentioned among
them some compounds are common among species, some others are
mostly restricted to other species; after that, medical advantages
based on some researches on species of this genus are reviewed;
different qualities such as anti-leishmania, anti-bacteria, antiviral as
well as anti-proliferative could be mentioned.
Abstract: In the present work, the effect of load and sliding
distance on the performance tribology of commercially used
aluminium-silicon engine block and piston was evaluated at ambient
conditions with humidity of 80% under dry sliding conditions using a
pin-on-disc with two different loads of 5N and 20N yielding applied
pressure of 0.30MPa and 1.4MPa, respectively, at sliding velocity of
0.29ms-1 and with varying sliding distance ranging from 260m-
4200m. Factors and conditions that had significant effect were
identified. The results showed that the load and the sliding distance
affect the wear rate of the alloys and the wear rate increased with
increasing load for both the alloys. Wear rate also increases almost
linearly at low loads and increase to a maximum then attain a plateau
with increasing sliding distance. For both applied loads the piston
alloy showed the better performance due to higher Ni and Mg
content. The worn surface and wear debris was characterized by
optical microscope, SEM and EDX analyzer. The worn surface was
characterized by surface with shallow grooves at loads while the
groove width and depth increased as the loads increases. Oxidative
wear was found to be the predominant mechanisms in the dry sliding
of Al-Si alloys at low loads.
Abstract: The purpose of this research was to identify factors
that influenced the success of e-commerce implementation within
SMEs businesses. In order to achieve the objectives of this research,
the researcher collected data from random firms in Thailand, both the
users and those who are not using the e-commerce. The data was
comprised of the results of 310 questionnaires, as well as 10
interviews with owner/managers of businesses who are currently
using e-commerce successfully. The data were analyzed by using
descriptive statistics, which included frequency, percentages, mean,
and the standard deviation of pertinent factors. Independent t-test and
one-way ANOVA test were also used. The findings of this research
revealed that 50% of all the firms surveyed had e-commerce website,
whereas, over 20% of all firms surveyed had developing an ecommerce
strategy. The result findings also indicate that
organizational factors, technological factors and environment factors
as significant factors effecting success of e-commerce
implementation in SMEs. From the hypotheses testing, the findings
revealed that the different level of support use ecommerce by
owner/manager had different success in e-commerce implementation.
Moreover, the difference in e-commerce management approach
affected the success in terms of higher total sales for the business or
higher number of retained or returning customers.
Abstract: The success of any retail business is predisposed by its
swift response and its knack in understanding the constraints and the
requirements of customers. In this paper a conceptual design model
of an automated customer-friendly supermarket has been proposed.
In this model a 10-sided, space benefited, regular polygon shaped
gravity shelves have been designed for goods storage and effective
customer-specific algorithms have been built-in for quick automatic
delivery of the randomly listed goods. The algorithm is developed
with two main objectives, viz., delivery time and priority. For
meeting these objectives the randomly listed items are reorganized
according to the critical-path of the robotic arm specific to the
identified shop and its layout and the items are categorized according
to the demand, shape, size, similarity and nature of the product for an
efficient pick-up, packing and delivery process. We conjectured that
the proposed automated supermarket model reduces business
operating costs with much customer satisfaction warranting a winwin
situation.
Abstract: In this work, we propose the application of Japanese
“Origami” art for a floating function of a small aerial vehicle such as a
hexarotor. A preliminary experiment was conducted using Origami
magic balls mounted under a hexarotor. This magic ball can expand
and shrink using an air pump during free flying. Using this interesting
and functional concept, it promises to reduce the resistance of wind as
well as reduce the energy consumption when the Origami balls are
deflated. This approach can be particularly useful in rescue emergency
situations. Furthermore, there are many unexpected reasons that may
cause the multi-rotor has to land on the surface of water due to
problems with the communication between the aircraft and the ground
station. In addition, a complementary experiment was designed to
prove that the hexarotor can fly maintaining the stability and also,
takes off and lands on the surface of water using air balloons.
Abstract: No matter how much perfect we become in our
practical skills regarding the implementation of learned ideas, the
need of technical writing capability cannot be neglected being a
professional. Technical writing is a way of communicating the ideas
in written which otherwise need to be presented orally. Technical
writing skills have always been the need of the time, as they are
required for internal as well as external official communication in
both formal and informal manner. Moreover, they are the best way to
capture the attention of your customers by presenting information in
effective manner. This paper aims to analyze the importance of
technical writing skills in professional industries of Pakistan by
conducting a survey. Survey results presented in this paper clearly
depicts the importance of formal and informal written communication
media used in different professional industries in Pakistan. Analysis
and discussion of the extent to which the alternative ways of
communication besides technical writing have got importance in
Pakistan is also an important aspect of this survey.
Abstract: The study deals with the challenges in developing a
test rig to test the performance of water lubricated journal bearing.
The test rig is designed to simulate the working conditions of the
bearing in order to understand their performance before they are put
in operation. The bearing that is studied is the commercially available
water lubricated bearing which has a rubber liner bonded with a rigid
metal shell. The lubricant enters the bearing axially through a
pressurized inlet tank and exits to an outlet tank which is at
sufficiently low pressure. The load on the bearing is applied through
the dead weight system which acts both in upward and downward
direction so that net load acts on the bearing. The issues in feeding
the lubricant into the bearing from the inlet side and preventing the
leakage of the lubricant is discussed. The application of the load on
the test bearing while maintaining the bearing afloat is also discussed.
Abstract: This research is aimed to develop the online-class
scheduling management system and improve as a complex problem
solution, this must take into consideration in various conditions and
factors. In addition to the number of courses, the number of students
and a timetable to study, the physical characteristics of each class
room and regulations used in the class scheduling must also be taken
into consideration. This system is developed to assist management in
the class scheduling for convenience and efficiency. It can provide
several instructors to schedule simultaneously. Both lecturers and
students can check and publish a timetable and other documents
associated with the system online immediately. It is developed in a
web-based application. PHP is used as a developing tool. The
database management system was MySQL. The tool that is used for
efficiency testing of the system is questionnaire. The system was
evaluated by using a Black-Box testing. The sample was composed
of 2 groups: 5 experts and 100 general users. The average and the
standard deviation of results from the experts were 3.50 and 0.67.
The average and the standard deviation of results from the general
users were 3.54 and 0.54. In summary, the results from the research
indicated that the satisfaction of users were in a good level.
Therefore, this system could be implemented in an actual workplace
and satisfy the users’ requirement effectively.