Abstract: In the past decade, the use of digital image correlation
(DIC) techniques has increased significantly in the area of
experimental mechanics, especially for materials behavior
characterization. This non-contact tool enables full field displacement
and strain measurements over a complete region of interest. The DIC
algorithm requires a random contrast pattern on the surface of the
specimen in order to perform properly. To create this pattern, the
specimen is usually first coated using a white matt paint. Next, a
black random speckle pattern is applied using any suitable method. If
the applied paint coating is too thick, its top surface may not be able
to exactly follow the deformation of the specimen, and consequently,
the strain measurement might be underestimated. In the present
article, a study of the influence of the paint thickness on the strain
underestimation is performed for different strain levels. The results
are then compared to typical paint coating thicknesses applied by
experienced DIC users. A slight strain underestimation was observed
for paint coatings thicker than about 30μm. On the other hand, this
value was found to be uncommonly high compared to coating
thicknesses applied by DIC users.
Abstract: Reticence is a prominent and complex phenomenon
which occurs in foreign language classrooms and influences students’
oral passivity. The present study investigated the extent in which
students experience reticence in the EFL classrooms and explored the
underlying factors triggering reticence. The participants were 104
Iranian freshmen undergraduate male and female EFL students, who
enrolled in listening and speaking courses, all majoring in English
studying at Islamic Azad University Isfahan (Khorasgan) Branch and
University of Isfahan, Isfahan, Iran. To collect the data, the Reticence
Scale-12 (RS-12) questionnaire which measures the level of reticence
consisting of six dimensions (anxiety, knowledge, timing,
organization, skills, and memory) was administered to the
participants. The statistical analyses showed that the reticent level
was high among the Iranian EFL undergraduate students, and their
major problems were feelings of anxiety and delivery skills.
Moreover, the results revealed that factors such as low English
proficiency, the teaching method, and lack of confidence contributed
to the students’ reticence in Iranian EFL classrooms. It can be
implied that language teachers’ awareness of learners’ reticence can
help them choose more appropriate activities and provide a friendly
environment enhancing hopefully more effective participation of EFL
learners. The findings can have implications for EFL teachers,
learners and policy makers.
Abstract: Students' academic achievement, along with the
effects of different variables, has been a serious concern of educators
since long ago. This study was an attempt to investigate the interplay
of Locus of Control (LOC), academic achievement and biological
variables among Iranian online EFL Learners. The participants of the
study included 100 students of different age groups and genders
studying English online at Iran Language Institute (ILI), Isfahan,
Iran. The instrument used was Trice Academic LOC questionnaire
which identifies orientations of internality or externality. The
participants' Grade Point Averages (GPAs) were used as the measure
of their academic achievement. A series of independent samples ttests
were performed on the data. The results of the study showed that
(a) there were no significant differences between male and female
participants in LOC orientation, (b) there was no relationship
between LOC and academic achievement among internal males and
females, (c) external females were better achievers than external
males, (d) and the age had no significant relationship with LOC and
academic achievement. It can be concluded that the social, cultural
patterns of genders have changed. This study might help sociologists
and psychologists as well as applied linguists in that they reflect the
recent social changes and their effects on the LOC and their
consequent implications in teaching languages.
Abstract: The objective of this paper is to present the process of
change in management accounting in Romania, a former communist
country from Eastern Europe. In order to explain this process, we used
the contingency and institutional theories. We focused on the
following directions: the presentation of the scientific context and
motivation of this research and the case study. We presented the state
of the art in the process of change in the management accounting from
the international and national perspective. We also described the
evolution of management accounting in Romania in the context of
economic and political changes. An important moment was the fall of
communism in 1989. This represents a starting point for a new
economic environment and for new management accounting.
Accordingly, we developed a case study which presented this
evolution. The conclusion of our research was that the changes in the
management accounting system of the company analysed occurred in
the same time with the institutionalisation of some elements (e.g.
degree of competition, training and competencies in management
accounting). The management accounting system was modelled by the
contingencies specific to this company (e.g. environment, industry,
strategy).
Abstract: Image segmentation and edge detection is a fundamental section in image processing. In case of noisy images Edge Detection is very less effective if we use conventional Spatial Filters like Sobel, Prewitt, LOG, Laplacian etc. To overcome this problem we have proposed the use of Stochastic Gradient Mask instead of Spatial Filters for generating gradient images. The present study has shown that the resultant images obtained by applying Stochastic Gradient Masks appear to be much clearer and sharper as per Edge detection is considered.
Abstract: Optimal feeding, including optimal micronutrient
intake, becomes one of the ways to overcome the long-term
consequences of undernutrition. Macronutrient and micronutrient
intake were important to a rapid growth and development of young
children. The study objective was to assess macro and micronutrient
intake and its adequacy in children aged 12-23 months. This survey
was a cross-sectional study, involving 83 caregivers with children
aged 12-23 months old in Senen Sub-district, Central Jakarta selected
through simple random sampling. Data on nutrient intake was
obtained through interview using single 24-hour recall. Repeated 24-
hour recall to sub-sample was done to estimate the proportion of
nutrient inadequacy. The highest prevalence of nutrient inadequacy
was iron (52.4%), followed by vitamin C (30.9%) and zinc (28.8%).
Almost 12% children had inadequate energy intake. More than half
of children (62.6%) were anemic (25.3% were severely anemic).
Micronutrient inadequacy, especially iron, was more problematic
than macronutrient inadequacy in the study area.
Abstract: Community integration is a construct that an
increasing body of research has shown to have a significant impact
on the wellbeing and recovery of people with psychiatric problems.
However, there are few studies that explore which factors can be
associated and predict community integration. Moreover, community
integration has been mostly studied in minority groups, and current
literature on the definition and manifestation of community
integration in the general population is scarcer. Thus, the current
study aims to characterize community integration and explore
possible predictor variables in a sample of participants with
psychiatric problems (PP, N=183) and a sample of participants from
the general population (GP, N=211).
Results show that people with psychiatric problems present above
average values of community integration, but are significantly lower
than their healthy counterparts. It was also possible to observe that
community integration does not vary in terms of the sociodemographic
characteristics of both groups in this study. Correlation
and multiple regression showed that, among several variables that
literature present as relevant in the community integration process,
only three variables emerged as having the most explanatory value in
community integration of both groups: sense of community, basic
needs satisfaction and submission. These results also shown that
those variables have increased explanatory power in the PP sample,
which leads us to emphasize the need to address this issue in future
studies and increase the understanding of the factors that can be
involved in the promotion of community integration, in order to
devise more effective interventions in this field.
Abstract: Paranoid ideation is a common thought process that
constitutes a defense against perceived social threats. The current
study aimed at the characterization of paranoid ideation in youths and
to explore the possible predictors involved in the development of
paranoid ideations. Paranoid ideation, shame, submission, early
childhood memories and current depressive, anxious and stress
symptomatology were assessed in a sample of 1516 Portuguese
youths. Higher frequencies of paranoid ideation were observed,
particularly in females and youths from lower socioeconomic status.
The main predictors identified relates to submissive behaviors and
adverse childhood experiences, and especially to shame feelings. The
current study emphasizes that the these predictors are similar to
findings in adults and clinical populations, and future implications to
research and clinical practice aiming at paranoid ideations are
discussed, as well as the pertinence of the study of mediating factors
that allow a wider understanding of this thought process in younger
populations and the prevention of psychopathology in adulthood.
Abstract: The substantial development of the construction
industry has forced the cement industry, its major support, to focus
on achieving maximum productivity to meet the growing demand for
this material. This means that the reliability of a cement production
system needs to be at the highest level that can be achieved by good
maintenance. This paper studies the extent to which the
implementation of RCM is needed as a strategy for increasing the
reliability of the production systems component can be increased,
thus ensuring continuous productivity. In a case study of four Libyan
cement factories, 80 employees were surveyed and 12 top and middle
managers interviewed. It is evident that these factories usually
breakdown more often than once per month which has led to a
decline in productivity. In many times they cannot achieve the
minimum level of production amount. This has resulted from the
poor reliability of their production systems as a result of poor or
insufficient maintenance. It has been found that most of the factories’
employees misunderstand maintenance and its importance. The main
cause of this problem is the lack of qualified and trained staff, but in
addition it has been found that most employees are not found to be
motivated as a result of a lack of management support and interest. In
response to these findings, it has been suggested that the RCM
strategy should be implemented in the four factories. The results
show the importance of the development of maintenance strategies
through the implementation of RCM in these factories. The purpose
of it would be to overcome the problems that could secure the
reliability of the production systems. This study could be a useful
source of information for academic researchers and the industrial
organizations which are still experiencing problems in maintenance
practices.
Abstract: Masonry infill walls are inevitable in the selfsupporting
structures, but their contribution in the resistance to
earthquake loads is generally neglected in the structural analyses. The
principal aim of this work through a numerical study of masonry
infill walls behavior in structures subjected to horizontal load is to
propose by finite elements numerical modeling, a more reliable
approach, faster and close to reality. In this study, 3D Finite Element
Analysis was developed to study the behavior of masonry infill walls
in structures subjected to horizontal load; the finite element software
being used was ABAQUS, it is observed that more rigidity of the
masonry filling is significant, more the structure is rigid, we can so
conclude that the filling brings an additional rigidity to the structure
not to be neglected; it is also observed that when the framework is
subjected to horizontal loads, the framework separates from the
filling on the level of the tended diagonal.
Abstract: Computational fluid dynamics analysis of the burning
of syngas fuels derived from biomass and plastic solid waste mixture
through gasification process is presented in this paper. The syngas
fuel is burned in gas turbine can combustor. Gas turbine can
combustor with swirl is designed to burn the fuel efficiently and
reduce the emissions. The main objective is to test the impact of the
alternative syngas fuel compositions and lower heating value on the
combustion performance and emissions. The syngas fuel is produced
by blending palm kernel shell (PKS) with polyethylene (PE) waste
via catalytic steam gasification (fluidized bed reactor). High
hydrogen content syngas fuel was obtained by mixing 30% PE waste
with PKS. The syngas composition obtained through the gasification
process is 76.2% H2, 8.53% CO, 4.39% CO2 and 10.90% CH4. The
lower heating value of the syngas fuel is LHV = 15.98 MJ/m3. Three
fuels were tested in this study natural gas (100%CH4), syngas fuel
and pure hydrogen (100% H2). The power from the combustor was
kept constant for all the fuels tested in this study. The effect of syngas
fuel composition and lower heating value on the flame shape, gas
temperature, mass of carbon dioxide (CO2) and nitrogen oxides
(NOX) per unit of energy generation is presented in this paper. The
results show an increase of the peak flame temperature and NO mass
fractions for the syngas and hydrogen fuels compared to natural gas
fuel combustion. Lower average CO2 emissions at the exit of the
combustor are obtained for the syngas compared to the natural gas
fuel.
Abstract: This study focuses on a novel method for dispersion
and distribution of reinforcement under high intensive shear stress to
produce metal composites. The polyacrylonitrile (PAN)-based short
carbon fiber (Csf) and Nextel 610 alumina fiber were dispersed under
high intensive shearing at mushy zone in semi-solid of A356 by a
novel method. The bundles and clusters were embedded by
infiltration of slurry into the clusters, thus leading to a uniform
microstructure. The fibers were embedded homogenously into the
aluminum around 576-580°C with around 46% of solid fraction.
Other experiments at 615°C and 568°C which are contained 0% and
90% solid respectively were not successful for dispersion and
infiltration of aluminum into bundles of Csf. The alumina fiber has
been cracked by high shearing load. The morphologies and
crystalline phase were evaluated by SEM and XRD. The adopted
thixo-process effectively improved the adherence and distribution of
Csf into Al that can be developed to produce various composites by
thixomixing.
Abstract: Microbes have been used to solve environmental
problems for many years. The role of microorganism to sequester,
precipitate or alter the oxidation state of various heavy metals has
been extensively studied. Treatment using microorganism interacts
with toxic metal are very diverse. The purpose of this research is to
remove the mercury using Pseudomonas putida (P. putida), pure
culture ATTC 49128 at optimum growth parameters such as
techniques of culture, acclimatization time and speed of incubator
shaker. Thus, in this study, the optimum growth parameters of P.
putida were obtained to achieve the maximum of mercury removal.
Based on the optimum parameters of P. putida for specific growth
rate, the removal of two different mercury concentration, 1 ppm and
4 ppm were studied. From mercury nitrate solution, a mercuryresistant
bacterial strain which is able to reduce from ionic mercury
to metallic mercury was used to reduce ionic mercury. The overall
levels of mercury removal in this study were between 80% and 89%.
The information obtained in this study is of fundamental for
understanding of the survival of P. putida ATTC 49128 in mercury
solution. Thus, microbial mercury removal is a potential
bioremediation for wastewater especially in petrochemical industries
in Malaysia.
Abstract: Five palm oil ether monoesters utilized as novel
biodiesels were synthesized and structurally identified in the paper.
The investigation was made on the effect of ether species on
physicochemical properties of the palm oil ether monoesters. The
results showed that density, kinematic viscosity, smoke point, and
solidifying point increase linearly with their –CH2 group number in
certain relationships. Cetane number is enhanced whereas heat value
decreases linearly with –CH2 group number. In addition, the
influencing regularities of the volumetric content of the palm oil ether
monoesters on the fuel properties were also studied when the ether
monoesters are used as diesel fuel additives.
Abstract: This paper deals with the study of reflection and
transmission characteristics of acoustic waves at the interface of a
semiconductor half-space and elastic solid. The amplitude ratios
(reflection and transmission coefficients) of reflected and transmitted
waves to that of incident wave varying with the incident angles have
been examined for the case of quasi-longitudinal wave. The special
cases of normal and grazing incidence have also been derived with
the help of Gauss elimination method. The mathematical model
consisting of governing partial differential equations of motion and
charge carriers’ diffusion of n-type semiconductors and elastic solid
has been solved both analytically and numerically in the study. The
numerical computations of reflection and transmission coefficients
has been carried out by using MATLAB programming software for
silicon (Si) semiconductor and copper elastic solid. The computer
simulated results have been plotted graphically for Si
semiconductors. The study may be useful in semiconductors,
geology, and seismology in addition to surface acoustic wave (SAW)
devices.
Abstract: Toddy sediment (TS) was cultured in a PDA medium
to determine initial yeast load, and also it was undergone sun, shade,
solar, dehumidified cold air (DCA) and hot air oven (at 400, 500 and
60oC) drying with a view to preserve viability of yeast. Thereafter,
this study was conducted according to two factor factorial design in
order to determine best preservation method. Therein the dried TS
from the best drying method was taken and divided into two portions.
One portion was mixed with 3: 7 ratio of TS: rice flour and the
mixture was divided in to two again. While one portion was kept
under in house condition the other was in a refrigerator. Same
procedure was followed to the rest portion of TS too but it was at the
same ratio of corn flour. All treatments were vacuum packed in triple
laminate pouches and the best preservation method was determined
in terms of leavening index (LI). The TS obtained from the best
preservation method was used to make foods (bread and hopper) and
organoleptic properties of it were evaluated against same of ordinary
foods using sensory panel with a five point hedonic scale.
Results revealed that yeast load or fresh TS was 58×106 CFU/g.
The best drying method in preserving viability of yeast was DCA
because LI of this treatment (96%) is higher than that of other three
treatments. Organoleptic properties of foods prepared from best
preservation method are as same as ordinary foods according to Duo
trio test.
Abstract: Pneumatic reactors have been widely employed in various sectors of the chemical industry, especially where are required high heat and mass transfer rates. This study aimed to obtain correlations that allow the prediction of gas hold-up (Ԑ) and volumetric oxygen transfer coefficient (kLa), and compare these values, for three models of pneumatic reactors on two scales utilizing Newtonian fluids. Values of kLa were obtained using the dynamic pressure-step method, while e was used for a new proposed measure. Comparing the three models of reactors studied, it was observed that the mass transfer was superior to draft-tube airlift, reaching e of 0.173 and kLa of 0.00904s-1. All correlations showed good fit to the experimental data (R2≥94%), and comparisons with correlations from the literature demonstrate the need for further similar studies due to shortage of data available, mainly for airlift reactors and high viscosity fluids.
Abstract: Potassium borates, which are widely used in welding
and metal refining industry, as a lubricating oil additive, cement
additive, fiberglass additive and insulation compound, are one of the
important groups of borate minerals. In this study the production of a
potassium borate mineral via hydrothermal method is aimed. The
potassium source of potassium nitrate (KNO3) was used along with a
sodium source of sodium hydroxide (NaOH) and boron source of
boric acid (H3BO3). The constant parameters of reaction temperature
and reaction time were determined as 80°C and 1 h, respectively. The
molar ratios of 1:1:3 (as KNO3:NaOH:H3BO3), 1:1:4, 1:1:5, 1:1:6
and 1:1:7 were used. Following the synthesis the identifications of
the produced products were conducted by X-Ray Diffraction (XRD),
Fourier Transform Infrared Spectroscopy (FT-IR) and Raman
Spectroscopy. The results of the experiments and analysis showed in
the ratio of 1:1:6, the Santite mineral with powder diffraction file
number (pdf no.) of 01-072-1688, which is known as potassium
pentaborate (KB5O8·4H2O) was synthesized as best.
Abstract: This paper presents the results of an experimental
study undertaken to evaluate the local bond stress-slip response of
short embedment of reinforcing bars in normal concrete (NC) and
high performance fiber reinforced cement composites (HPFRCC)
blocks. Long embedment was investigated as well to gain insights on
the distribution of strain, slip, bar stress and bond stress along the bar
especially in post-yield range. A total of 12 specimens were tested,
by means of pull-out of the reinforcing bars from concrete blocks. It
was found that the enhancement of local bond strength can be
reached up to 50% and ductility of the bond behavior was improved
significantly if HPFRCC is used. Also, under a constant strain at
loaded end, HPFRCC has delayed yielding of bars at other location
from the loaded end. Hence, the reduction of bond stress was slower
for HPFRCC in comparison with NC. Due to the same reason, the
total slips at loaded end for HPFRCC was smaller than NC as
expected. Test results indicated that HPFRCC has better bond slip
behavior which makes it a suitable material to be employed in
anchorage zone such as beam-column joints.
Abstract: The effect of partially substitution of magnetic
impurity Fe for Cu to the magnetic and transport properties in
electron-doped superconducting cuprates of
Eu1.85+yCe0.15-yCu1-yFeyO4+α-δ (ECCFO) with y = 0, 0.010, 0.020, and
0.050 has been studied, in order to investigate the mechanism of
magnetic and transport properties of ECCFO in normal-state.
Magnetic properties are investigated by DC magnetic-susceptibility
measurements that carried out at low temperatures down to 2 K using a
standard SQUID magnetometer in a magnetic field of 5 Oe on field
cooling. Transport properties addressed to electron mobility, are
extracted from radius of electron localization calculated from
temperature dependence of resistivity. For y = 0, temperature
dependence of dc magnetic-susceptibility (χ) indicated the change of
magnetic behavior from paramagnetic to diamagnetic below 15 K.
Above 15 K, all samples show paramagnetic behavior with the values
of magnetic moment in every volume unit increased with increasing y.
Electron mobility decreased with increasing y.