Abstract: This paper presents a new structure of microstrip band
pass filter (BPF) based on coupled stepped impedance resonators.
Each filter consists of two coupled stepped impedance resonators
connected to microstrip feed lines. The coupled junction is utilized to
connect the two BPFs to the antenna. This two band pass filters are
designed and simulated to operate for the digital communication
system (DCS) and Industrial Scientific and Medical (ISM) bands at
1.8 GHz and 2.45 GHz respectively. The proposed circuit presents
good performances with an insertion loss lower than 2.3 dB and
isolation between the two channels greater than 21 dB. The prototype
of the optimized diplexer have been investigated numerically by
using ADS Agilent and verified with CST microwave software.
Abstract: Carbon fiber reinforced polymersarewidely used to strengthen steel structural elements. These structural elements are normally subjected to static, dynamic and fatigue loadings during their life-time. CFRP laminate is commonly used to strengthen these structures under the subjected loads. A number of studies have focused on the characteristics of CFRP sheets bonded to steel members under static, dynamic and fatigue loadings. However, there is a gap in understanding the bonding behavior between CFRP laminates and steel members under impact loading. This paper shows the effect of high load rates on this bond. CFRP laminate CFK 150/2000 was used to strengthen steel joints using Araldite 420 epoxy. The results show that applying a high load rate significantly affects the bond strength but has little influence on the effective bond length.
Abstract: In this study, attempt has been made to investigate the
relationship specifically the causal relation between fund unit prices
of Islamic equity unit trust fund which measure by fund NAV and the
selected macro-economic variables of Malaysian economy by using
VECM causality test and Granger causality test. Monthly data has
been used from Jan, 2006 to Dec, 2012 for all the variables. The
findings of the study showed that industrial production index,
political election and financial crisis are the only variables having
unidirectional causal relationship with fund unit price. However the
global oil price is having bidirectional causality with fund NAV.
Thus, it is concluded that the equity unit trust fund industry in
Malaysia is an inefficient market with respect to the industrial
production index, global oil prices, political election and financial
crisis. However the market is approaching towards informational
efficiency at least with respect to four macroeconomic variables,
treasury bill rate, money supply, foreign exchange rate, and
corruption index.
Abstract: The thermal conductivity of a fluid can be
significantly enhanced by dispersing nano-sized particles in it, and
the resultant fluid is termed as "nanofluid". A theoretical model for
estimating the thermal conductivity of a nanofluid has been proposed
here. It is based on the mechanism that evenly dispersed
nanoparticles within a nanofluid undergo Brownian motion in course
of which the nanoparticles repeatedly collide with the heat source.
During each collision a rapid heat transfer occurs owing to the solidsolid
contact. Molecular dynamics (MD) simulation of the collision
of nanoparticles with the heat source has shown that there is a pulselike
pick up of heat by the nanoparticles within 20-100 ps, the extent
of which depends not only on thermal conductivity of the
nanoparticles, but also on the elastic and other physical properties of
the nanoparticle. After the collision the nanoparticles undergo
Brownian motion in the base fluid and release the excess heat to the
surrounding base fluid within 2-10 ms. The Brownian motion and
associated temperature variation of the nanoparticles have been
modeled by stochastic analysis. Repeated occurrence of these events
by the suspended nanoparticles significantly contributes to the
characteristic thermal conductivity of the nanofluids, which has been
estimated by the present model for a ethylene glycol based nanofluid
containing Cu-nanoparticles of size ranging from 8 to 20 nm, with
Gaussian size distribution. The prediction of the present model has
shown a reasonable agreement with the experimental data available
in literature.
Abstract: In this study the instability problem of a modified
Taylor-Couette flow between two vertical coaxial cylinders of radius
R1, R2 is considered. The modification is based on the wavy shape of
the inner cylinder surface, where inner cylinders with different
surface amplitude and wavelength are used. The study aims to
discover the effect of the inner surface geometry on the instability
phenomenon that undergoes Taylor-Couette flow. The study reveals
that the transition processes depends strongly on the amplitude and
wavelength of the inner cylinder surface and resulting in flow
instabilities that are strongly different from that encountered in the
case of the classical Taylor-Couette flow.
Abstract: Artificial Neural Network (ANN) can be trained using
back propagation (BP). It is the most widely used algorithm for
supervised learning with multi-layered feed-forward networks.
Efficient learning by the BP algorithm is required for many practical
applications. The BP algorithm calculates the weight changes of
artificial neural networks, and a common approach is to use a twoterm
algorithm consisting of a learning rate (LR) and a momentum
factor (MF). The major drawbacks of the two-term BP learning
algorithm are the problems of local minima and slow convergence
speeds, which limit the scope for real-time applications. Recently the
addition of an extra term, called a proportional factor (PF), to the
two-term BP algorithm was proposed. The third increases the speed
of the BP algorithm. However, the PF term also reduces the
convergence of the BP algorithm, and criteria for evaluating
convergence are required to facilitate the application of the three
terms BP algorithm. Although these two seem to be closely related,
as described later, we summarize various improvements to overcome
the drawbacks. Here we compare the different methods of
convergence of the new three-term BP algorithm.
Abstract: There exists some time lag between the consumption of
inputs and the production of outputs. This time lag effect should be
considered in calculating efficiency of decision making units (DMU).
Recently, a couple of DEA models were developed for considering
time lag effect in efficiency evaluation of research activities. However,
these models can’t discriminate efficient DMUs because of the nature
of basic DEA model in which efficiency scores are limited to ‘1’. This
problem can be resolved a super-efficiency model. However, a super
efficiency model sometimes causes infeasibility problem. This paper
suggests an output oriented super-efficiency model for efficiency
evaluation under the consideration of time lag effect. A case example
using a long term research project is given to compare the suggested
model with the MpO model.
Abstract: Developing young people’s employability is a key
policy issue for ensuring their successful transition to the labour
market and their access to career oriented employment. The youths of
today irrespective of their gender need to acquire the knowledge,
skills and attitudes that will enable them to create or find jobs as well
as cope with unpredictable labour market changes throughout their
working lives. In a study carried out to determine the influence of
gender on job-competencies requirements of chemical-based
industries and undergraduate-competencies acquisition by chemists
working in the industries, all chemistry graduates working in twenty
(20) chemical-based industries that were randomly selected from six
sectors of chemical-based industries in Lagos and Ogun States of
Nigeria were administered with Job-competencies required and
undergraduate-competencies acquired assessment questionnaire. The
data were analysed using means and independent sample t-test. The
findings revealed that the population of female chemists working in
chemical-based industries is low compared with the number of male
chemists; furthermore, job-competencies requirements are found not
to be gender biased while there is no significant difference in
undergraduate-competencies acquisition of male and female
chemists. This suggests that females should be given the same
opportunity of employment in chemical-based industries as their male
counterparts. The study also revealed the level of acquisition of
undergraduate competencies as related to the needs of chemicalbased
industries.
Abstract: In this paper, effect of marginal quality groundwater
on yield of cotton crop and soil salinity was studied. In this
connection, three irrigation treatments each with four replications
were applied. These treatments were i) use of canal water (T1), ii) use
of marginal quality groundwater from tubewell (T2), and iii)
conjunctive use by mixing with the ratio of 1:1 of canal water and
marginal quality tubewell water (T3).
Water was applied to the crop cultivated in Kharif season 2011; its
quantity has been measured using cut-throat flume. Total 11 watering
each of 50 mm depth have been applied from 20th April to 20th July,
2011. Further, irrigations were stopped due to monsoon rainfall up to
crop harvesting.
Maximum crop yield (seed cotton) was observed under T1 which
was 1,517 kg/ha followed by T3 (mixed canal and tubewell water)
having 1009 kg/ha and T2 i.e. marginal quality groundwater having
709 kg/ha. This concludes that crop yield in T2 and T3 in comparison
to T1was reduced by about 53 and 30% respectively.
It has been observed that yield of cotton crop is below potential
limit for three treatments due to unexpected rainfall at the time of full
flowering season; thus the yield was adversely affected.
However, salt deposition in soil profiles was not observed that is
due to leaching effect of heavy rainfall occurred during monsoon
season.
Abstract: In this study which has been conducted in Akçasu
Forest Range District of Devrek Forest Directorate; 3 methods (weed
control with labourer power, cover removal with Hitachi F20
Excavator, and weed control with agricultural equipment mounted on
a Ferguson 240S agriculture tractor) were utilized in weed control
efforts in regeneration of degraded oriental beech forests have been
compared. In this respect, 3 methods have been compared by
determining certain work hours and standard durations of unit areas
(1 hectare). For this purpose, evaluating the tasks made with human
and machine force from the aspects of duration, productivity and
costs, it has been aimed to determine the most productive method in
accordance with the actual ecological conditions of research field.
Within the scope of the study, the time studies have been conducted
for 3 methods used in weed control efforts. While carrying out those
studies, the performed implementations have been evaluated by
dividing them into business stages. Also, the actual data have been
used while calculating the cost accounts. In those calculations, the
latest formulas and equations which are also used in developed
countries have been utilized. The variance of analysis (ANOVA) was
used in order to determine whether there is any statistically
significant difference among obtained results, and the Duncan test
was used for grouping if there is significant difference. According to
the measurements and findings carried out within the scope of this
study, it has been found during living cover removal efforts in
regeneration efforts in demolished oriental beech forests that the
removal of weed layer in 1 hectare of field has taken 920 hours with
labourer force, 15.1 hours with excavator and 60 hours with an
equipment mounted on a tractor. On the other hand, it has been
determined that the cost of removal of living cover in unit area (1
hectare) was 3220.00 TL for labourer power, 1250 TL for excavator
and 1825 TL for equipment mounted on a tractor.
According to the obtained results, it has been found that the
utilization of excavator in weed control effort in regeneration of
degraded oriental beech regions under actual ecological conditions of
research field has been found to be more productive from both of
aspects of duration and costs. These determinations carried out
should be repeated in weed control efforts in degraded forest fields
with different ecological conditions, it is compulsory for finding the
most efficient weed control method. These findings will light the way
of technical staff of forestry directorate in determination of the most
effective and economic weed control method. Thus, the more actual
data will be used while preparing the weed control budgets, and there
will be significant contributions to national economy. Also the results of this and similar studies are very important for developing the policies for our forestry in short and long term.
Abstract: Over the last few decades, oilfield service rolling
equipment has significantly increased in weight, primarily because of
emissions regulations, which require larger/heavier engines, larger
cooling systems, and emissions after-treatment systems, in some
cases, etc. Larger engines cause more vibration and shock loads,
leading to failure of electronics and control systems.
If the vibrating frequency of the engine matches the system
frequency, high resonance is observed on structural parts and mounts.
One such existing automated control equipment system comprising
wire rope mounts used for mounting computers was designed
approximately 12 years ago. This includes the use of an industrialgrade
computer to control the system operation. The original
computer had a smaller, lighter enclosure. After a few years, a newer
computer version was introduced, which was 10 lbm heavier. Some
failures of internal computer parts have been documented for cases in
which the old mounts were used. Because of the added weight, there
is a possibility of having the two brackets impact each other under
off-road conditions, which causes a high shock input to the computer
parts. This added failure mode requires validating the existing mount
design to suit the new heavy-weight computer.
This paper discusses the modal finite element method (FEM)
analysis and experimental modal analysis conducted to study the
effects of vibration on the wire rope mounts and the computer. The
existing mount was modelled in ANSYS software, and resultant
mode shapes and frequencies were obtained. The experimental modal
analysis was conducted, and actual frequency responses were
observed and recorded.
Results clearly revealed that at resonance frequency, the brackets
were colliding and potentially causing damage to computer parts. To
solve this issue, spring mounts of different stiffness were modeled in
ANSYS software, and the resonant frequency was determined.
Increasing the stiffness of the system increased the resonant
frequency zone away from the frequency window at which the engine
showed heavy vibrations or resonance. After multiple iterations in
ANSYS software, the stiffness of the spring mount was finalized,
which was again experimentally validated.
Abstract: Many wireless sensor network applications require
K-coverage of the monitored area. In this paper, we propose a
scalable harmony search based algorithm in terms of execution
time, K-Coverage Enhancement Algorithm (KCEA), it attempts to
enhance initial coverage, and achieve the required K-coverage degree
for a specific application efficiently. Simulation results show that
the proposed algorithm achieves coverage improvement of 5.34%
compared to K-Coverage Rate Deployment (K-CRD), which achieves
1.31% when deploying one additional sensor. Moreover, the proposed
algorithm is more time efficient.
Abstract: In order to manufacture short gap single Si nanowire
(NW) field effect transistor (FET) by imprinting and transferring
method, we introduce the method using Al2O3 sacrificial layer. The
diameters of cylindrical Si NW addressed between Au electrodes by
dielectrophoretic (DEP) alignment method are controlled to 106, 128,
and 148 nm. After imprinting and transfer process, cylindrical Si NW
is embedded in PVP adhesive and dielectric layer. By curing
transferred cylindrical Si NW and Au electrodes on PVP-coated p++ Si
substrate with 200nm-thick SiO2, 3μm gap Si NW FET fabrication
was completed. As the diameter of embedded Si NW increases, the
mobility of FET increases from 80.51 to 121.24 cm2/V·s and the
threshold voltage moves from –7.17 to –2.44 V because the ratio of
surface to volume gets reduced.
Abstract: The recommended limit for cadmium concentration in
potable water is less than 0.005 mg/L. A continuous biosorption
process using indigenous red seaweed, Gracilaria corticata, was
performed to remove cadmium from the potable water. The process
was conducted under fixed conditions and the breakthrough curves
were achieved for three consecutive sorption-desorption cycles. A
modeling based on Artificial Neural Network (ANN) was employed
to fit the experimental breakthrough data. In addition, a simplified
semi empirical model, Thomas, was employed for this purpose. It
was found that ANN well described the experimental data (R2>0.99)
while the Thomas prediction were a bit less successful with R2>0.97.
The adjusted design parameters using the nonlinear form of Thomas
model was in a good agreement with the experimentally obtained
ones. The results approve the capability of ANN to predict the
cadmium concentration in potable water.
Abstract: Background: Taiwan now is an aging society. Research
on the elderly should not be confined to caring for seniors, but should
also be focused on ways to improve health and the quality of life.
Senior citizens who participate in volunteer services could become
less lonely, have new growth opportunities, and regain a sense of
accomplishment. Thus, the question of how to get the elderly to
participate in volunteer service is worth exploring. Objective: Apply
the Transtheoretical Model to understand stages of change in regular
volunteer service and voluntary service behaviour among the seniors.
Methods: 1525 adults over the age of 65 from the Renai district of
Keelung City were interviewed. The research tool was a
self-constructed questionnaire, and individual interviews were
conducted to collect data. Then the data was processed and analyzed
using the IBM SPSS Statistics 20 (Windows version) statistical
software program. Results: In the past six months, research subjects
averaged 9.92 days of volunteer services. A majority of these elderly
individuals had no intention to change their regular volunteer services.
We discovered that during the maintenance stage, the self-efficacy for
volunteer services was higher than during all other stages, but
self-perceived barriers were less during the preparation stage and
action stage. Self-perceived benefits were found to have an important
predictive power for those with regular volunteer service behaviors in
the previous stage, and self-efficacy was found to have an important
predictive power for those with regular volunteer service behaviors in
later stages. Conclusions/Implications for Practice: The research
results support the conclusion that community nursing staff should
group elders based on their regular volunteer services change stages
and design appropriate behavioral change strategies.
Abstract: Science and technology has a major impact on many
societal domains such as communication, medicine, food,
transportation, etc. However, this dominance of modern technology
can have a negative unintended impact on indigenous systems, and in
particular on indigenous foods. This problem serves as a motivation
to this study whose aim is to examine the perceptions of learners on
the usefulness of Information and Communication Technologies
(ICTs) for learning about indigenous foods. This aim will be
subdivided into two types of research objectives. The design and
identification of theories and models will be achieved using literature
content analysis. The objective on the empirical testing of such
theories and models will be achieved through the survey of
Hospitality studies learners from different schools in the iLembe and
Umgungundlovu Districts of the South African Kwazulu-Natal
province. SPSS is used to quantitatively analyze the data collected by
the questionnaire of this survey using descriptive statistics and
Pearson correlations after the assessment of the validity and the
reliability of the data. The main hypothesis behind this study is that
there is a connection between the demographics of learners, their
perceptions on the usefulness of ICTs for learning about indigenous
foods, and the following personality and eLearning related theories
constructs: Computer self-efficacy, Trust in ICT systems, and
Conscientiousness; as suggested by existing studies on learning
theories. This hypothesis was fully confirmed by the survey
conducted by this study except for the demographic factors where
gender and age were not found to be determinant factors of learners’
perceptions on the usefulness of ICTs for learning about indigenous
foods.
Abstract: Geopolymer concretes are new class of construction
materials that have emerged as an alternative to Ordinary Portland
cement concrete. Considerable researches have been carried out on
material development of geopolymer concrete; however, a few studies
have been reported on the structural use of them. This paper presents
the bond behaviors of reinforcement embedded in fly ash based
geopolymer concrete. The development lengths of reinforcement for
various compressive strengths of concrete, 20, 30 and 40 MPa, and
reinforcement diameters, 10, 16 and 25 mm, are investigated. Total 27
specimens were manufactured and pull-out test according to EN 10080
was applied to measure bond strength and slips between concrete and
reinforcements. The average bond strengths decreased from 23.06MPa
to 17.26 MPa, as the diameters of reinforcements increased from
10mm to 25mm. The compressive strength levels of geopolymer
concrete showed no significant influence on bond strengths in this
study. Also, the bond-slip relations between geopolymer concrete and
reinforcement are derived using non-linear regression analysis for
various experimental conditions.
Abstract: Systems Engineering plays a key role during industrial
product development of complex technical systems. The need for
systems engineers in industry is growing. But there is a gap between
the industrial need and the academic education. Normally the
academic education is focused on the domain specific design,
implementation and testing of technical systems. Necessary systems
engineering expertise like knowledge about requirements analysis,
product cost estimation, management or social skills are poorly
taught. Thus there is the need of new academic concepts for teaching
systems engineering skills. This paper presents a project-orientated
training concept to prepare students from different technical degree
programs for systems engineering activities. The training concept has
been initially implemented and applied in the industrial engineering
master program of the University of Applied Sciences Offenburg.
Abstract: The problematic of gender and socioeconomic status
biased differences in academic motivation patterns is discussed.
Gender identity is understood according to symbolic interactionism
perspective: as a result of reflected appraisals, social comparisons,
self-attributions, and identifications, shaped by social environment
and family context. The effects of socioeconomic status on academic
motivation are conceptualized according to Bourdieu’s habitus
concept, reflecting the role of unconscious and internalized cultural
signals, proper to low and high socioeconomic status family contexts.
Since families differ by various socioeconomic features, the
hypothesis about possible impact of parents’ socioeconomic status on
their children’s academic motivation interfering with gender
socialization effects is held. The survey, aiming to seize gender
differences in academic motivation and self-recorded improvementoriented
efforts as a result of socialization processes operating in the
families of low and high socioeconomic status, was designed. The
results of Lithuanian higher education students’ survey are presented
and discussed.
Abstract: Nowadays, Photovoltaic-PV Farms/ Parks and large
PV-Smart Grid Interface Schemes are emerging and commonly
utilized in Renewable Energy distributed generation. However, PVhybrid-
Dc-Ac Schemes using interface power electronic converters
usually has negative impact on power quality and stabilization of
modern electrical network under load excursions and network fault
conditions in smart grid. Consequently, robust FACTS based
interface schemes are required to ensure efficient energy utilization
and stabilization of bus voltages as well as limiting switching/fault
onrush current condition. FACTS devices are also used in smart grid-
Battery Interface and Storage Schemes with PV-Battery Storage
hybrid systems as an elegant alternative to renewable energy
utilization with backup battery storage for electric utility energy and
demand side management to provide needed energy and power
capacity under heavy load conditions. The paper presents a robust
interface PV-Li-Ion Battery Storage Interface Scheme for
Distribution/Utilization Low Voltage Interface using FACTS
stabilization enhancement and dynamic maximum PV power tracking
controllers.
Digital simulation and validation of the proposed scheme is done
using MATLAB/Simulink software environment for Low Voltage-
Distribution/Utilization system feeding a hybrid Linear-Motorized
inrush and nonlinear type loads from a DC-AC Interface VSC-6-
pulse Inverter Fed from the PV Park/Farm with a back-up Li-Ion
Storage Battery.