Abstract: The structures obtained with the use of sandwich
technologies combine low weight with high energy absorbing
capacity and load carrying capacity. Hence, there is a growing and
markedly interest in the use of sandwiches with aluminum foam core
because of very good properties such as flexural rigidity and energy
absorption capability. In the current investigation, the static threepoint
bending tests were carried out on the sandwiches with
aluminum foam core and glass fiber reinforced polymer (GFRP)
skins at different values of support span distances aiming the analyses
of their flexural performance. The influence of the core thickness and
the GFRP skin type was reported in terms of peak load and energy
absorption capacity. For this purpose, the skins with two different
types of fabrics which have same thickness value and the aluminum
foam core with two different thicknesses were bonded with a
commercial polyurethane based flexible adhesive in order to combine
the composite sandwich panels. The main results of the bending tests
are: force-displacement curves, peak force values, absorbed energy,
collapse mechanisms and the effect of the support span length and
core thickness. The results of the experimental study showed that the
sandwich with the skins made of S-Glass Woven fabrics and with the
thicker foam core presented higher mechanical values such as load
carrying and energy absorption capacities. The increment of the
support span distance generated the decrease of the mechanical
values for each type of panels, as expected, because of the inverse
proportion between the force and span length. The most common
failure types of the sandwiches are debonding of the lower skin and
the core shear. The obtained results have particular importance for
applications that require lightweight structures with a high capacity
of energy dissipation, such as the transport industry (automotive,
aerospace, shipbuilding and marine industry), where the problems of
collision and crash have increased in the last years.
Abstract: In today’s rapidly changing and increasingly complex
environment, organizations have relied on their members’ positive
attitude toward their employers. In particular, employees’
organizational commitment (primarily, the affective component) has
been recognized as an essential component of organizational
functioning and success. Hence, identifying the determinants of
affective commitment is one of the most important research issues.
This study tested the influence of leader-member exchange (LMX)
and exchange ideology on employee’s affective commitment. In
addition, the interactive effect of LMX and exchange ideology was
examined. Data from 198 members of the Korean military supports
each of the hypotheses. Lastly, implications for research and directions
for future research are discussed.
Abstract: The strawberry tree (Arbutus unedo L.) is a small tree
or shrub from botanical Ericaceae family that grows spontaneously
nearby the Mediterranean basin and produce edible red fruits. A
traditional processed fruit application, in Mediterranean countries, is
the production of a spirit (known as aguardente de medronho, in
Portugal) obtained from the fermented fruit. The main objective of
our study was to contribute to the knowledge about the influence of
the degree of maturation of fruits in the volatile composition and
quality of arbutus spirit. The major volatiles in the three distillates
fractions (head, heart and tail) obtained from fermentation of two
different fruit maturation levels were quantified by GC-FID analysis
and ANOVA one-way was performed. Additionally, the total
antioxidant capacity and total phenolic compounds of both arbutus
fruit spirits were determined, by ABTS and Folin-Ciocalteau method,
respectively. The methanol concentration is higher (1022.39 g/hL
a.a.) in the spirit made from fruits with highest total soluble solids,
which is a value above the legal limit (1000 g/hL a.a.). Overall, our
study emphasizes, for the first time, the influence of maturation
degree of arbutus fruits in the spirit volatile composition and quality.
Abstract: During the post-Civil War era, the city of Nashville,
Tennessee, had the highest mortality rate in the United States. The
elevated death and disease rates among former slaves were
attributable to lack of quality healthcare. To address the paucity of
healthcare services, Meharry Medical College, an institution with the
mission of educating minority professionals and serving the
underserved population, was established in 1876.
Purpose: The social ecological framework and partial least squares
(PLS) path modeling were used to quantify the impact of
socioeconomic status and adverse health outcome on primary care
professionals serving the disadvantaged community. Thus, the study
results could demonstrate the accomplishment of the College’s
mission of training primary care professionals to serve in underserved
areas.
Methods: Various statistical methods were used to analyze alumni
data from 1975 – 2013. K-means cluster analysis was utilized to
identify individual medical and dental graduates in the cluster groups
of the practice communities (Disadvantaged or Non-disadvantaged
Communities). Discriminant analysis was implemented to verify the
classification accuracy of cluster analysis. The independent t-test was
performed to detect the significant mean differences of respective
clustering and criterion variables. Chi-square test was used to test if
the proportions of primary care and non-primary care specialists are
consistent with those of medical and dental graduates practicing in
the designated community clusters. Finally, the PLS path model was
constructed to explore the construct validity of analytic model by
providing the magnitude effects of socioeconomic status and adverse
health outcome on primary care professionals serving the
disadvantaged community.
Results: Approximately 83% (3,192/3,864) of Meharry Medical
College’s medical and dental graduates from 1975 to 2013 were
practicing in disadvantaged communities. Independent t-test confirmed the content validity of the cluster analysis model. Also, the
PLS path modeling demonstrated that alumni served as primary care
professionals in communities with significantly lower socioeconomic
status and higher adverse health outcome (p < .001). The PLS path
modeling exhibited the meaningful interrelation between primary
care professionals practicing communities and surrounding
environments (socioeconomic statues and adverse health outcome),
which yielded model reliability, validity, and applicability.
Conclusion: This study applied social ecological theory and
analytic modeling approaches to assess the attainment of Meharry
Medical College’s mission of training primary care professionals to
serve in underserved areas, particularly in communities with low
socioeconomic status and high rates of adverse health outcomes. In
summary, the majority of medical and dental graduates from Meharry
Medical College provided primary care services to disadvantaged
communities with low socioeconomic status and high adverse health
outcome, which demonstrated that Meharry Medical College has
fulfilled its mission. The high reliability, validity, and applicability of
this model imply that it could be replicated for comparable
universities and colleges elsewhere.
Abstract: Introduction: There are multiple social, individual and
cultural factors that influence an individual’s decision to adopt family
planning methods especially among non-users in patriarchal societies
like Pakistan. Non-users, if targeted efficiently, can contribute
significantly to country’s CPR. A research study showed that nonusers
if convinced to adopt lactational amenorrhea method can shift
to long term methods in future. Research shows that if non users are
targeted efficiently a 59% reduction in unintended pregnancies in
Saharan Africa and South-Central and South-East Asia is anticipated.
Methods: We did secondary data analysis on Pakistan
Demographic Heath Survey (2012-13) dataset. Use of contraception
(never-use/ever-use) was the outcome variable. At univariate level
Chi-square/Fisher Exact test was used to assess relationship of
baseline covariates with contraception use. Then variables to be
incorporated in the model were checked for multicollinearity,
confounding and interaction. Then binary logistic regression (with an
urban-rural stratification) was done to find relationship between
contraception use and baseline demographic and social variables.
Results: The multivariate analyses of the study showed that
younger women (≤ 29 years)were more prone to be never users as
compared to those who were >30 years and this trend was seen in
urban areas (AOR 1.92, CI 1.453-2.536) as well as rural areas (AOR
1.809, CI 1.421-2.303). While looking at regional variation, women
from urban Sindh (AOR 1.548, CI 1.142-2.099) and urban
Balochistan (AOR 2.403, CI 1.504-3.839) had more never users as
compared to other urban regions. Women in the rich wealth quintile
were more never users and this was seen both in urban and rural
localities (urban (AOR 1.106 CI .753-1.624); rural areas (AOR 1.162,
CI .887-1.524)) even though these were not statistically significant.
Women idealizing more children (>4) are more never users as
compared to those idealizing less children in both urban (AOR 1.854,
CI 1.275-2.697) and rural areas (AOR 2.101, CI 1.514-2.916).
Women who never lost a pregnancy were more inclined to be nonusers
in rural areas (AOR 1.394, CI 1.127-1.723) .Women familiar
with only traditional or no method had more never users in rural areas
(AOR 1.717, CI 1.127-1.723) but in urban areas it wasn’t significant.
Women unaware of Lady Health Worker’s presence in their area
were more never users especially in rural areas (AOR 1.276, CI
1.014-1.607). Women who did not visit any care provider were more
never users (urban (AOR 11.738, CI 9.112-15.121) rural areas (AOR
7.832, CI 6.243-9.826)).
Discussion/Conclusion: This study concluded that government,
policy makers and private sector family planning programs should
focus on the untapped pool of never users (younger women from underserved provinces, in higher wealth quintiles, who desire more
children.). We need to make sure to cover catchment areas where
there are less LHWs and less providers as ignorance to modern
methods and never been visited by an LHW are important
determinants of never use. This all is in sync with previous literate
from similar developing countries.
Abstract: Crosstalk among interconnects and printed-circuit
board (PCB) traces is a major limiting factor of signal quality in highspeed
digital and communication equipments especially when fast
data buses are involved. Such a bus is considered as a planar
multiconductor transmission line. This paper will demonstrate how
the finite difference time domain (FDTD) method provides an exact
solution of the transmission-line equations to analyze the near end
and the far end crosstalk. In addition, this study makes it possible to
analyze the rise time effect on the near and far end voltages of the
victim conductor. The paper also discusses a statistical analysis,
based upon a set of several simulations. Such analysis leads to a
better understanding of the phenomenon and yields useful
information.
Abstract: Big Data and analytics have gained a huge momentum
in recent years. Big Data feeds into the field of Learning Analytics
(LA) that may allow academic institutions to better understand the
learners’ needs and proactively address them. Hence, it is important
to have an understanding of Big Data and its applications. The
purpose of this descriptive paper is to provide an overview of Big
Data, the technologies used in Big Data, and some of the applications
of Big Data in education. Additionally, it discusses some of the
concerns related to Big Data and current research trends. While Big
Data can provide big benefits, it is important that institutions
understand their own needs, infrastructure, resources, and limitation
before jumping on the Big Data bandwagon.
Abstract: This study presented to reduce earthquake damage and
emergency rehabilitation of critical structures such as schools, hightech
factories, and hospitals due to strong ground motions associated
with climate changes. Regarding recent trend, a strong earthquake
causes serious damage to critical structures and then the critical
structure might be influenced by sequence aftershocks (or tsunami)
due to fault plane adjustments. Therefore, in order to improve seismic
performance of critical structures, retrofitted or strengthening study
of the structures under aftershocks sequence after emergency
rehabilitation of the structures subjected to strong earthquakes is
widely carried out. Consequently, this study used composite material
for emergency rehabilitation of the structure rather than concrete and
steel materials because of high strength and stiffness, lightweight,
rapid manufacturing, and dynamic performance. Also, this study was
to develop or improve the seismic performance or seismic retrofit of
critical structures subjected to strong ground motions and earthquake
aftershocks, by utilizing GFRP-Corrugated Infill Panels (GCIP).
Abstract: ABC classification is widely used by managers for
inventory control. The classical ABC classification is based on Pareto
principle and according to the criterion of the annual use value only.
Single criterion classification is often insufficient for a closely
inventory control. Multi-criteria inventory classification models have
been proposed by researchers in order to consider other important
criteria. From these models, we will consider a specific model in
order to make a sensitive analysis on the composite score calculated
for each item. In fact, this score, based on a normalized average
between a good and a bad optimized index, can affect the ABC-item
classification. We will focus on items differently assigned to classes
and then propose a classification compromise.
Abstract: Objects are usually horizontally sliced when printed by 3D printers. Therefore, if an object to be printed, such as a collection of fibers, originally has natural direction in shape, the printed direction contradicts with the natural direction. By using proper tools, such as field-oriented 3D paint software, field-oriented solid modelers, field-based tool-path generation software, and non-horizontal FDM 3D printers, the natural direction can be modeled and objects can be printed in a direction that is consistent with the natural direction. This consistence results in embodiment of momentum or force in expressions of the printed object. To achieve this goal, several design and manufacturing problems, but not all, have been solved. An application of this method is (Japanese) 3D calligraphy.
Abstract: Recently, there is a lot of interest in the field of under
water optical wireless communication for short range because of
its high bandwidth. But in most of the previous works line of
sight propagation or single scattering of photons only considered.
In practical case this is not applicable because of beam blockage in
underwater and multiple scattering also occurred during the photons
propagation through water. In this paper we consider a non-line
of sight underwater wireless optical communication system with
multiple scattering and examine the performance of the system using
monte carlo simulation. The distribution scattering angle of photons
are modeled by Henyey-Greenstein method. The average bit error
rate is calculated using on-off keying modulation for different water
types.
Abstract: Egg yolk oil is a natural source of bioactive
compounds such as unsaturated fatty acids, oil soluble vitamins,
pigments and others. Bioactive compound content in egg yolk oil
depends from its content in eggs, from which oil was extracted. Many
studies show that bioactive compound content in egg is correlated to
the content of these compounds in hen feed, but there is also an
opinion that hen housing systems also have influence on egg
chemical content. The aim of this study was to determine which
factor, laying hen housing system or hen diet, has a primary influence
on bioactive compound content in egg yolk oil. The egg yolk oil was
extracted from eggs obtained from 4 different hen housing systems:
cage, barn and two groups of free range. All hens were fed with
commercially produced compound feed except one group of free
range hens which get free diet – pastured hens. Extracted egg yolk
oils were analyzed for fatty acids, oil soluble vitamins and β-carotene
content. α-tocopherol, ergocalcipherol and polyunsaturated fatty acid
content in egg yolk oil was higher from eggs obtained from all
housing systems where hens were fed with commercial compound
feed. β-carotene and retinol content in egg yolk oils from free range
free diet eggs was significantly (p>0.05) higher that from other eggs
because hens have access to green forage. Hen physical activity in
free range housing systems decreases content of some bioactive
compound in egg yolk oil.
Abstract: Image compression based on fractal coding is a lossy
compression method and normally used for gray level images range
and domain blocks in rectangular shape. Fractal based digital image
compression technique provide a large compression ratio and in this
paper, it is proposed using YUV colour space and the fractal theory
which is based on iterated transformation. Fractal geometry is mainly
applied in the current study towards colour image compression
coding. These colour images possesses correlations among the colour
components and hence high compression ratio can be achieved by
exploiting all these redundancies. The proposed method utilises the
self-similarity in the colour image as well as the cross-correlations
between them. Experimental results show that the greater
compression ratio can be achieved with large domain blocks but more
trade off in image quality is good to acceptable at less than 1 bit per
pixel.
Abstract: Behavioral aspects of experience such as will power
are rarely subjected to quantitative study owing to the numerous
complexities involved. Will is a phenomenon that has puzzled
humanity for a long time. It is a belief that will power of an individual
affects the success achieved by them in life. It is also thought that a
person endowed with great will power can overcome even the most
crippling setbacks in life while a person with a weak will cannot make
the most of life even the greatest assets. This study is an attempt
to subject the phenomena of will to the test of an artificial neural
network through a computational model. The claim being tested is
that will power of an individual largely determines success achieved
in life. It is proposed that data pertaining to success of individuals
be obtained from an experiment and the phenomenon of will be
incorporated into the model, through data generated recursively using
a relation between will and success characteristic to the model.
An artificial neural network trained using part of the data, could
subsequently be used to make predictions regarding data points in
the rest of the model. The procedure would be tried for different
models and the model where the networks predictions are found to
be in greatest agreement with the data would be selected; and used
for studying the relation between success and will.
Abstract: In the present work, Electrochemical Impedance
Spectrocopy (EIS) is applied to study the transport of different metal
cations through a cation-exchange membrane. This technique enables
the identification of the ionic-transport characteristics and to
distinguish between different transport mechanisms occurring at
different current density ranges. The impedance spectra are
dependent on the applied dc current density, on the type of cation and
on the concentration.
When the applied dc current density increases, the diameter of the
impedance spectra loops increases because all the components of
membrane system resistance increase. The diameter of the impedance
plots decreases in the order of Na(I), Ni(II) and Cr(III) due to the
increased interactions between the negatively charged sulfonic
groups of the membrane and the cations with greater charge. Nyquist
plots are shifted towards lower values of the real impedance, and its
diameter decreases with the increase of concentration due to the
decrease of the solution resistance.
Abstract: High pressure turbine (HPT) blades of DV – 2 jet
engines are made from Ni – based superalloy. This alloy was
originally manufactured in the Soviet Union and referred as ŽS6K.
For improving alloy’s high temperature resistance are blades coated
with Al – Si diffusion layer. A regular operation temperature of HPT
blades vary from 705°C to 750°C depending on jet engine regime.
An overcrossing working temperature range causes degradation of
the protective coating as well as base material which microstructure
is formed by the gamma matrix and strengthening phase gamma
prime (forming small particles in the microstructure). Diffusion
processes inside the material during exposition of the material to high
temperatures causes mainly coarsening of the gamma prime particles,
thus decreasing its strengthening effect. Degradation of the Al – Si
coating caused its thickness growth. All the microstructure changes
and coating layer thickness growth results in decreasing of the turbine
blade operation lifetime.
Abstract: A central element of higher education today is the
“core” or “general education” curriculum: that configuration of
courses that often encompasses the essence of liberal arts education.
Ensuring that such offerings reflect the mission and values of the
institution is a challenge faced by most college and universities, often
more than once. This paper presents an action model of program
planning designed to structure the processes of developing,
implementing and revising core curricula in a manner consistent with
key institutional goals and objectives. Through presentation of a case
study from a university in the United States, the elements of needs
assessment, stakeholder investment and collaborative compromise
are shown as key components of a planning strategy that can produce
a general education program that is comprehensive, academically
rigorous, assessable, and mission consistent. The paper concludes
with recommendations for both the implementation and evaluation of
such programs in practice.
Abstract: This paper is part of a study to develop robots for
farming. As such power requirement to operate equipment attach to
such robots become an important factor. Soil-tool interaction plays
major role in power consumption, thus predicting accurately the
forces which act on the blade during the farming is very important for
optimal designing of farm equipment. In this paper, a finite element
investigation for tillage tools and soil interaction is described by
using an inelastic constitutive material law for agriculture
application. A 3-dimensional (3D) nonlinear finite element analysis
(FEA) is developed to examine behavior of a blade with different
rake angles moving in a block of soil, and to estimate the blade force.
The soil model considered is an elastic-plastic with non-associated
Drucker-Prager material model. Special use of contact elements are
employed to consider connection between soil-blade and soil-soil
surfaces. The FEA results are compared with experimental ones,
which show good agreement in accurately predicting draft forces
developed on the blade when it moves through the soil. Also a very
good correlation was obtained between FEA results and analytical
results from classical soil mechanics theories for straight blades.
These comparisons verified the FEA model developed. For analyzing
complicated soil-tool interactions and for optimum design of blades,
this method will be useful.
Abstract: Indonesian higher education has experienced
significant changes over the last decade. In 1999, the government
published an overall strategy for decentralisation and enhancement of
local autonomy in many sectors, including (higher) education.
Indonesian higher education reforms have forced universities to
restructure their internal university governance to become more
entrepreneurial. These new types of internal university governance
are likely to affect the institutions’ leadership and management. This
paper discusses the approach and findings of a study on the
managerial leadership styles of deans in Indonesian universities. The
study aims to get a better understanding of styles exhibited by deans
manifested in their behaviours. Using the theories of reasoned action
and planned behaviour, in combination with the competing values
framework, a large-scale survey was conducted to gather information
on the deans’ behaviours, attitudes, subjective norms, and perceived
behavioural control. Based on the responses of a sample of 218
deans, the study identifies a number of leadership styles: the Master,
the Competitive Consultant, the Consensual Goal-Setter, the Focused
Team Captain, and the Informed Trust-Builder style. The study
demonstrates that attitudes are the primary determinant of the styles
that were found. Perceived behavioural control is a factor that
explains some managerial leadership styles. By understanding the
attitudes of deans in Indonesian universities, and their leadership
styles, universities can strengthen their management and governance,
and thus improve their effectiveness.
Abstract: In the past few years, the amount of malicious software
increased exponentially and, therefore, machine learning algorithms
became instrumental in identifying clean and malware files through
(semi)-automated classification. When working with very large
datasets, the major challenge is to reach both a very high malware
detection rate and a very low false positive rate. Another challenge
is to minimize the time needed for the machine learning algorithm to
do so. This paper presents a comparative study between different
machine learning techniques such as linear classifiers, ensembles,
decision trees or various hybrids thereof. The training dataset consists
of approximately 2 million clean files and 200.000 infected files,
which is a realistic quantitative mixture. The paper investigates the
above mentioned methods with respect to both their performance
(detection rate and false positive rate) and their practicability.