Abstract: This paper investigates the parametric stability of an
axially moving web subjected to non-uniform in-plane edge
excitations on two opposite, simply-supported edges. The web is
modeled as a viscoelastic plate whose constitutive relation obeys the
Kelvin-Voigt model, and the in-plane edge excitations are expressed
as the sum of a static tension and a periodical perturbation. Due to the
in-plane edge excitations, the moving plate may bring about
parametric instability under certain situations. First, the in-plane
stresses of the plate due to the non-uniform edge excitations are
determined by solving the in-plane forced vibration problem. Then,
the dependence on the spatial coordinates in the equation of transverse
motion is eliminated by the generalized Galerkin method, which
results in a set of discretized system equations in time. Finally, the
method of multiple scales is utilized to solve the set of system
equations analytically if the periodical perturbation of the in-plane
edge excitations is much smaller as compared with the static tension of
the plate, from which the stability boundaries of the moving plate are
obtained. Numerical results reveal that only combination resonances
of the summed-type appear under the in-plane edge excitations
considered in this work.
Abstract: Aurèsregion is one of the arid and semi-arid areas that
have suffered climate crises and overexploitation of natural resources
they have led to significant land degradation. The use of remote sensing data allowed us to analyze the land and
its spatiotemporal changes in the Aurès between 1987 and 2013, for
this work, we adopted a method of analysis based on the exploitation
of the images satellite Landsat TM 1987 and Landsat OLI 2013, from
the supervised classification likelihood coupled with field surveys of
the mission of May and September of 2013. Using ENVI EX software by the superposition of the ground cover
maps from 1987 and 2013, one can extract a spatial map change of
different land cover units. The results show that between 1987 and
2013 vegetation has suffered negative changes are the significant
degradation of forests and steppe rangelands, and sandy soils and
bare land recorded a considerable increase. The spatial change map land cover units between 1987 and 2013
allows us to understand the extensive or regressive orientation of
vegetation and soil, this map shows that dense forests give his place
to clear forests and steppe vegetation develops from a degraded forest
vegetation and bare, sandy soils earn big steppe surfaces that explain
its remarkable extension.
The analysis of remote sensing data highlights the profound
changes in our environment over time and quantitative monitoring of
the risk of desertification.
Abstract: Numerical investigations were conducted to study the
influence of flexural reinforcement ratio on the diagonal cracking
strength and ultimate shear strength of reinforced concrete (RC)
beams without stirrups. Three-dimensional nonlinear finite element
analyses (FEAs) of the beams with flexural reinforcement ratios
ranging from 0.58% to 2.20% subjected to a mid-span concentrated
load were carried out. It is observed that the load-deflection and loadstrain
curves obtained from the numerical analyses agree with those
obtained from the experiments. It is concluded that flexural
reinforcement ratio has a significant effect on the shear strength and
deflection capacity of RC beams without stirrups. The predictions of
diagonal cracking strength and ultimate shear strength of beams
obtained by using the equations defined by a number of codes and
researchers are compared with each other and with the experimental
values.
Abstract: This paper presents a state-of-the-art survey of the
operations research models developed for internal audit planning.
Two alternative approaches have been followed in the literature for
audit planning: (1) identifying the optimal audit frequency; and (2)
determining the optimal audit resource allocation. The first approach
identifies the elapsed time between two successive audits, which can
be presented as the optimal number of audits in a given planning
horizon, or the optimal number of transactions after which an audit
should be performed. It also includes the optimal audit schedule. The
second approach determines the optimal allocation of audit frequency
among all auditable units in the firm. In our review, we discuss both
the deterministic and probabilistic models developed for audit
planning. In addition, game theory models are reviewed to find the
optimal auditing strategy based on the interactions between the
auditors and the clients.
Abstract: Research Objectives: The roles and activities of
Human Resource Management (HRM) have changed a lot in the past
years. Driven by a changing environment and therefore new business
requirements, the scope of human resource (HR) activities has
widened. The extent to which these activities should focus on
strategic issues to support the long term success of a company has
been discussed in science for many years. As many economies of
Central and Eastern Europe (CEE) experienced a phase of transition
after the socialist era and are now recovering from the 2008 global
crisis it is needed to examine the current state of HR positioning.
Furthermore a trend in HR work developing from rather
administrative units to being strategic partners of management can be
noticed. This leads to the question of better understanding the
underlying competencies which are necessary to support
organisations. This topic was addressed by the international study
“HR Competencies in international comparison”. The quantitative
survey was conducted by the Institute for Human Resources &
Organisation of FHWien University of Applied Science of WKW (A)
in cooperation with partner universities in the countries Bosnia-
Herzegovina, Croatia, Serbia and Slovenia. Methodology: Using the
questionnaire developed by Dave Ulrich we tested whether the HR
Competency model can be used for Austria, Bosnia and Herzegovina,
Croatia, Serbia and Slovenia. After performing confirmatory and
exploratory factor analysis for the whole data set containing all five
countries we could clearly distinguish between four competencies. In
a further step our analysis focused on median and average
comparisons between the HR competency dimensions. Conclusion:
Our literature review, in alignment with other studies, shows a
relatively rapid pace of development of HR Roles and HR
Competencies in BCSS in the past decades. Comparing data from
BCSS and Austria we still can notice that regards strategic orientation
there is a lack in BCSS countries, thus competencies are not as
developed as in Austria. This leads us to the tentative conclusion that
HR has undergone a rapid change but is still in a State of Transition
from being a rather administrative unit to performing the role of a
strategic partner.
Abstract: This study examined whether big five personality traits
affect game addiction with control of psychological, social, and
demographic factors. Specifically, using data from a survey of 789
game users in Korea, we conducted a regression analysis to see the
associations of psychological (loneliness/depression), social (activities
with family/friends), self-efficacy (game/general), gaming (daily
gaming time/perception), demographic (age/gender), and personality
traits (extraversion, neuroticism conscientiousness, agreeableness, &
openness) with the degree of game addiction. Results showed that
neuroticism increase game addiction with no effect of extraversion on
the addiction. General self-efficacy negatively affected game
addiction, whereas game self-efficacy increased the degree of game
addiction. Loneliness enhanced game addiction while depression
showed a negative effect on the addiction. Results and implications are
discussed.
Abstract: In present global scenario, aluminum alloys are
coining the attention of many innovators as competing structural
materials for automotive and space applications. Comparing to other
challenging alloys, especially, 7xxx series aluminum alloys have
been studied seriously because of benefits such as moderate strength;
better deforming characteristics and affordable cost. It is expected
that substitution of aluminum alloys for steels will result in great
improvements in energy economy, durability and recyclability.
However, it is necessary to improve the strength and the formability
levels at low temperatures in aluminum alloys for still better
applications. Aluminum–Zinc–Magnesium with or without other
wetting agent denoted as 7XXX series alloys are medium strength
heat treatable alloys. In addition to Zn, Mg as major alloying
additions, Cu, Mn and Si are the other solute elements which
contribute for the improvement in mechanical properties by suitable
heat treatment process. Subjecting to suitable treatments like age
hardening or cold deformation assisted heat treatments; known as low
temperature thermomechanical treatments (LTMT) the challenging
properties might be incorporated. T6 is the age hardening or
precipitation hardening process with artificial aging cycle whereas T8
comprises of LTMT treatment aged artificially with X% cold
deformation. When the cold deformation is provided after solution
treatment, there is increase in hardness related properties such as
wear resistance, yield and ultimate strength, toughness with the
expense of ductility. During precipitation hardening both hardness
and strength of the samples are increasing. The hardness value may
further improve when room temperature deformation is positively
supported with age hardening known as thermomechanical treatment.
It is intended to perform heat treatment and evaluate hardness, tensile
strength, wear resistance and distribution pattern of reinforcement in
the matrix. 2 to 2.5 and 3 to 3.5 times increase in hardness is reported
in age hardening and LTMT treatments respectively as compared to
as-cast composite. There was better distribution of reinforcements in
the matrix, nearly two fold increase in strength levels and up to 5
times increase in wear resistance are also observed in the present
study.
Abstract: Acoustic properties of polymeric liquids are high
sensitive to free gas traces in the form of fine bubbles. Their presence
is typical for such liquids because of chemical reactions, small
wettability of solid boundaries, trapping of air in technological
operations, etc. Liquid temperature influences essentially its
rheological properties, which may have an impact on the bubble
pulsations and sound propagation in the system. The target of the
paper is modeling of the liquid temperature effect on single bubble
dynamics and sound dispersion and attenuation in polymeric solution
with spherical gas bubbles. The basic sources of attenuation (heat
exchange between gas in microbubbles and surrounding liquid,
rheological and acoustic losses) are taken into account. It is supposed
that in the studied temperature range the interface mass transfer has a
minor effect on bubble dynamics. The results of the study indicate
that temperature raise yields enhancement of bubble pulsations and
increase in sound attenuation in the near-resonance range and may
have a strong impact on sound dispersion in the liquid-bubble
mixture at frequencies close to the resonance frequency of bubbles.
Abstract: Numerical studies have been carried out using a
validated two-dimensional standard k-omega turbulence model for
the design optimization of a thrust vector control system using shock
induced self-impinging supersonic secondary double jet. Parametric
analytical studies have been carried out at different secondary
injection locations to identifying the highest unsymmetrical
distribution of the main gas flow due to shock waves, which produces
a desirable side force more lucratively for vectoring. The results from
the parametric studies of the case on hand reveal that the shock
induced self-impinging supersonic secondary double jet is more
efficient in certain locations at the divergent region of a CD nozzle
than a case with supersonic single jet with same mass flow rate. We
observed that the best axial location of the self-impinging supersonic
secondary double jet nozzle with a given jet interaction angle, built-in
to a CD nozzle having area ratio 1.797, is 0.991 times the primary
nozzle throat diameter from the throat location. We also observed
that the flexible steering is possible after invoking ON/OFF facility to
the secondary nozzles for meeting the onboard mission requirements.
Through our case studies we concluded that the supersonic self-impinging
secondary double jet at predesigned jet interaction angle
and location can provide more flexible steering options facilitating
with 8.81% higher thrust vectoring efficiency than the conventional
supersonic single secondary jet without compromising the payload
capability of any supersonic aerospace vehicle.
Abstract: In this paper air quality conditions in Makkah and
Leeds are compared. These two cities have totally different climatic
conditions. Makkah climate is characterised as hot and dry (arid)
whereas that of Leeds is characterised as cold and wet (temperate).
This study uses air quality data from 2012 collected in Makkah,
Saudi Arabia and Leeds, UK. The concentrations of all pollutants,
except NO are higher in Makkah. Most notable, the concentrations of
PM10 are much higher in Makkah than in Leeds. This is probably due
to the arid nature of climatic conditions in Makkah and not solely due
to anthropogenic emission sources, otherwise like PM10 some of the
other pollutants, such as CO, NO, and SO2 would have shown much
greater difference between Leeds and Makkah. Correlation analysis is
performed between different pollutants at the same site and the same
pollutants at different sites. In Leeds the correlation between PM10
and other pollutants is significantly stronger than in Makkah. Weaker
correlation in Makkah is probably due to the fact that in Makkah
most of the gaseous pollutants are emitted by combustion processes,
whereas most of the PM10 is generated by other sources, such as
windblown dust, re-suspension, and construction activities. This is in
contrast to Leeds where all pollutants including PM10 are
predominantly emitted by combustions, such as road traffic.
Furthermore, in Leeds frequent rains wash out most of the
atmospheric particulate matter and suppress re-suspension of dust.
Temporal trends of various pollutants are compared and discussed.
This study emphasises the role of climatic conditions in managing air
quality, and hence the need for region-specific controlling strategies
according to the local climatic and meteorological conditions.
Abstract: Studying stress and strain trends in the femur and
recognizing femur failure mechanism is very important for
preventing hip fracture in the elderly. The aim of this study was to
identify high stress and strain regions in the femur during normal
walking and falling to find the mechanical behavior and failure
mechanism of the femur. We developed a finite element model of the
femur from the subject’s quantitative computed tomography (QCT)
image and used it to identify potentially high stress and strain regions
during the single-leg stance and the sideways fall. It was found that
fracture may initiate from the superior region of femoral neck and
propagate to the inferior region during a high impact force such as
sideways fall. The results of this study showed that the femur bone is
more sensitive to strain than stress which indicates the effect of
strain, in addition to effect of stress, should be considered for failure
analysis.
Abstract: Present work deals with the possible use of fertigation
in agriculture and its impact on the availability of mineral nitrogen
(Nmin) in topsoil and subsoil horizons. The aim of the present study is
to demonstrate the effect of the organic matter presence in fertigation
on microbial transformation and availability of mineral nitrogen
forms. The main investigation reason is the potential use of pretreated
waste water, as a source of organic carbon (Corg) and residual
nutrients (Nmin) for fertigation. Laboratory experiment has been
conducted to demonstrate the effect of the arable land fertilization
method on the Nmin availability in different depths of the soil with
the usage of model experimental containers filled with soil from
topsoil and podsoil horizons that were taken from the precise area.
Tufted hairgrass (Deschampsia caespitosa) has been chosen as a
model plant. The water source protection zone Brezova nad Svitavou
has been a research area where significant underground reservoirs of
drinking water of the highest quality are located. From the second
half of the last century local sources of drinking water show
nitrogenous compounds increase that get here almost only from
arable lands. Therefore, an attention of the following text focuses on
the fate of mineral nitrogen in the complex plant-soil. Research
results show that the fertigation application with Corg in a
combination with mineral fertilizer can reduce the amount of Nmin
leached from topsoil horizon of agricultural soils. In addition, some
plants biomass production reduces may occur.
Abstract: The using of waste materials in the construction
industry can reduce the dependence on the natural aggregates which
are going at the end to deplete. The glass waste is generated in a huge
amount which can make one of its disposals in concrete industry
effective not only as a green solution but also as an advantage to
enhance the performance of mechanical properties and durability of
concrete. This article reports the performance of concrete specimens
containing different percentages of milled glass waste as a partial
replacement of cement (Powder), when they are subject to cycles of
freezing and thawing. The tests were conducted on 75-mm cubes and
75 x 75 x 300-mm prisms. Compressive strength based on laboratory
testing and non-destructive ultrasonic pulse velocity test were
performed during the action of freezing-thawing cycles (F/T). The
results revealed that the incorporation of glass waste in concrete
mixtures is not only feasible but also showed generally better strength
and durability performance than control concrete mixture. It may be
said that the recycling of waste glass in concrete mixes is not only a
disposal way, but also it can be an exploitation in concrete industry.
Abstract: SARA is a common and serious metabolic disorder in
early lactation in dairy cattle and in finishing beef cattle, caused by
diets with high inclusion of cereal grain. This experiment was
performed to determine the efficacy of Megasphaera elsdenii, a
major lactate-utilizing bacterium in prevention/treatment of SARA in
vivo. In vivo experimentation, it was used eight ruminally cannulated
rams and it was applied the rapid adaptation with the mixture of grain
based on wheat (80% wheat, 20% barley) and barley (80% barley,
20% wheat). During the systematic adaptation, it was followed the
probability of SARA formation by being measured the rumen pH
with two hours intervals after and before feeding. After being
evaluated the data, it was determined the ruminal pH ranged from
5.2-5.6 on the condition of feeding with 60 percentage of grain
mixture based on barley and wheat, that assured the definite form of
subacute acidosis. In four days SARA period, M. elsdenii (1010 cfu
ml-1) was inoculated during the first two days. During the SARA
period, it was observed the decrease of feed intake with M. elsdenii
inoculation. Inoculation of M. elsdenii was caused to differentiation
of rumen pH (P
Abstract: The work aims to develop a robot in the form of
autonomous vehicle to detect, inspection and mapping of
underground pipelines through the ATmega328 Arduino platform.
Hardware prototyping is very similar to C / C ++ language that
facilitates its use in robotics open source, resembles PLC used in
large industrial processes. The robot will traverse the surface
independently of direct human action, in order to automate the
process of detecting buried pipes, guided by electromagnetic
induction. The induction comes from coils that send the signal to the
Arduino microcontroller contained in that will make the difference in
intensity and the treatment of the information, and then this
determines actions to electrical components such as relays and
motors, allowing the prototype to move on the surface and getting the
necessary information. This change of direction is performed by a
stepper motor with a servo motor. The robot was developed by
electrical and electronic assemblies that allowed test your application.
The assembly is made up of metal detector coils, circuit boards and
microprocessor, which interconnected circuits previously developed
can determine, process control and mechanical actions for a robot
(autonomous car) that will make the detection and mapping of buried
pipelines plates. This type of prototype can prevent and identifies
possible landslides and they can prevent the buried pipelines suffer an
external pressure on the walls with the possibility of oil leakage and
thus pollute the environment.
Abstract: A knowledge base stores facts and rules about the
world that applications can use for the purpose of reasoning. By
applying the concept of granular computing to a knowledge base,
several advantages emerge. These can be harnessed by applications
to improve their capabilities and performance. In this paper, the
concept behind such a construct, called a granular knowledge cube,
is defined, and its intended use as an instrument that manages to
cope with different data types and detect knowledge domains is
elaborated. Furthermore, the underlying architecture, consisting of the
three layers of the storing, representing, and structuring of knowledge,
is described. Finally, benefits as well as challenges of deploying it
are listed alongside application types that could profit from having
such an enhanced knowledge base.
Abstract: Neural activity in the human brain starts from the
early stages of prenatal development. This activity or signals
generated by the brain are electrical in nature and represent not only
the brain function but also the status of the whole body. At the
present moment, three methods can record functional and
physiological changes within the brain with high temporal resolution
of neuronal interactions at the network level: the
electroencephalogram (EEG), the magnet oencephalogram (MEG),
and functional magnetic resonance imaging (fMRI); each of these has
advantages and shortcomings. EEG recording with a large number of
electrodes is now feasible in clinical practice. Multichannel EEG
recorded from the scalp surface provides very valuable but indirect
information about the source distribution. However, deep electrode
measurements yield more reliable information about the source
locations intracranial recordings and scalp EEG are used with the
source imaging techniques to determine the locations and strengths of
the epileptic activity. As a source localization method, Low
Resolution Electro-Magnetic Tomography (LORETA) is solved for
the realistic geometry based on both forward methods, the Boundary
Element Method (BEM) and the Finite Difference Method (FDM). In
this paper, we review the findings EEG- LORETA about epilepsy.
Abstract: This paper proposes a linear model for optimizing
domestic energy consumption in Romania. The particularity of the
model is that it is putting in competition both tangible technologies
and thermal insulation projects with different financing modes.
The model is optimizing the energy system by minimizing the
global discounted cost in household sector, by integrating residential
lighting, space heating, hot water, combined space heating – hot
water, as well as space cooling, in a monolithic model. Another
demand sector included is the passenger transport.
This paper focuses on space heating part, analyzing technical and
economic issues related to investment decisions to envelope and
insulate buildings, in order to minimize energy consumption.
Abstract: In this paper, an experiment was conducted to assess
the impact of online deliberation on citizens’ attitudes. Specifically,
this research compared pre and post deliberation opinions of
participants who deliberated online via an asynchronous platform
regarding the issue of political opinion polls. Results indicate that
online deliberation had a positive effect on citizens’ attitudes since it
was found that following deliberation participants changed their
views regarding public opinion polls. Specifically, online deliberation
improved discussants perceptions regarding the reliability of polls,
while suppressing their negative views about the misuse of polls by
media, polling organizations and politicians.
Abstract: It is a major challenge to build a bridge superstructure
that has long-term durability and low maintenance requirements. A
solution to this challenge may be to use new materials or to
implement new structural systems. Fiber Reinforced Polymer (FRP)
composites have continued to play an important role in solving some
of persistent problems in infrastructure applications because of its
high specific strength, light weight, and durability. In this study, the
concept of the hybrid FRP-concrete structural systems is applied to a
bridge superstructure. The hybrid FRP-concrete bridge superstructure
is intended to have durable, structurally sound, and cost effective
hybrid system that will take full advantage of the inherent properties
of both FRP materials and concrete. In this study, two hybrid FRP-concrete
bridge systems were investigated. The first system consists
of trapezoidal cell units forming a bridge superstructure. The second
one is formed by arch cells. The two systems rely on using cellular
components to form the core of the bridge superstructure, and an
outer shell to warp around those cells to form the integral unit of the
bridge. Both systems were investigated analytically by using finite
element (FE) analysis. From the rigorous FE studies, it was
concluded that first system is more efficient than the second.