Abstract: The article presents two mathematical models of the
interaction between a rotating shaft and an incompressible fluid. The
mathematical model includes both the journal bearings and the
axially traversed hydrodynamic sealing gaps of hydraulic machines.
A method is shown for the identification of additional effects of the
fluid acting on the rotor of the machine, both for a linear and a nonlinear
model. The interaction is expressed by matrices of mass,
stiffness and damping.
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: 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: Moringa oleifera is a nutritious vegetable tree with
varieties of potential uses, as almost every part of the Moringa
oleifera tree can be used for food. This study was conducted in Oyo
State, Nigeria, to find out the level of acceptability of Moringa
oleifera diversified products among rural and urban dwellers.
Purposive sampling was used to select two local governments’ areas.
Stratified sampling technique was also used to select one community
each from rural and urban areas while snowball sampling technique
was used to select ten respondents each from the two communities,
making a total number of forty respondents. Data were analyzed
using frequencies, percentages, Chi-square, Pearson Product Moment
Correlation and regression analysis. Result from the study revealed
that majority of the respondents (80%) fell within the age range of
20-49 years and 55% of them were male, 55% were married, 70% of
them were Christians, 80% of them had tertiary education. The result
also showed that 85% were aware of the Moringa plant and (65%) of
them have consumed Moringa oleifera and the perception statements
on the benefits of Moringa oleifera indicated that (52.5%) of the
respondents rated Moringa oleifera to be favorable, most of them had
high acceptability for Moringa egusi soup, Moringa tea, Moringa pap
and yam pottage with Moringa. The result of the hypotheses testing
showed that there is a significant relationship between sex of the
respondents and acceptability of the diversified Moringa oleifera
products (x2=6.465, p = 0.011). There is also a significant
relationship between family size of the respondents level of
acceptability of the Moringa oleifera products (r = 0.327, p = 0.040).
Based on the level of acceptability of Moringa oleifera diversified
products; the plant is of great economic importance to the populace.
Therefore, there should be more public awareness through the media
to enlighten people on the beneficial effects of Moringa oleifera.
Abstract: A total of 115 yeast strains isolated from local cassava
processing wastes were measured for crude protein content. Among
these strains, the strain MSY-2 possessed the highest protein
concentration (>3.5 mg protein/mL). By using molecular
identification tools, it was identified to be a strain of Pichia
kudriavzevii based on similarity of D1/D2 domain of 26S rDNA
region. In this study, to optimize the protein production by MSY-2
strain, Response Surface Methodology (RSM) was applied. The
tested parameters were the carbon content, nitrogen content, and
incubation time. Here, the value of regression coefficient (R2) =
0.7194 could be explained by the model which is high to support the
significance of the model. Under the optimal condition, the protein
content was produced up to 3.77 g per L of the culture and MSY-2
strain contains 66.8 g protein per 100 g of cell dry weight. These
results revealed the plausibility of applying the novel strain of yeast
in single-cell protein production.
Abstract: The first part of the paper analyzes the dynamics of
the total fertility rate both at the national and regional level, pointing
out the regional disparities in the distribution of this indicator. At the
same time, we also focus on the collapse of the number of live births,
on the changes in the fertility rate by birth rank, as well as on the
failure of acquiring the desired number of children. The second part
of the study centres upon a survey applied to urban families with 3
and more than 3 offspring. The preliminary analysis highlights the
fact that an increased fertility (more than 3rd rank) is triggered by the
parents’ above the average material condition and superior education.
The current situation of Romania, which is still passing through a
period of relatively rapid demographic changes, marked by numerous
convulsions, requires a new approach, in compliance with the recent
interpretations appropriate to a new post-transitional demographic
regime.
Abstract: The aims of this study were to determine the factor
structure and psychometric properties (i.e., reliability and convergent
validity) of the Malaysian Multi-Ethnic Discrimination Scale
(MMEDS). It consists of 71-items measure experience, strategies
used and consequences of ethnic discrimination. A sample of 649
university students from one of the higher education institution in
Malaysia was asked to complete MMEDS, as well as Perceived
Ethnic and Racial Discrimination. The exploratory factor analysis on
ethnic discrimination experience extracted two factors labeled ‘unfair
treatment’ (15 items) and ‘Denial of the ethnic right’ (12 items)
which accounted for 60.92% of the total variance. The two sub scales
demonstrated clear reliability with internal consistency above .70.
The convergent validity of the Scale was supported by an expected
pattern of correlations (positive and significant correlation) between
the score of unfair treatment and denial of the ethnic right and the
score of Perceived Ethnic and Racial Discrimination by Peers Scale.
The results suggest that the MMEDS is a reliable and valid measure.
However, further studies need to be carried out in other groups of
sample as to validate the Scale.
Abstract: Fly ash (FA) thanks to the significant presence of SiO2
and Al2O3 as the main components is a potential raw material for
geopolymers production. Mechanical activation is a method for
improving FA reactivity and also the porosity of final mixture; those
parameters can be analysed through sorption properties. They have
direct impact on the durability of fly ash based geopolymer mortars.
In the paper, effect of FA fineness on sorption properties of
geopolymers based on sodium silicate, as well as relationship
between fly ash fineness and apparent density, compressive and
flexural strength of geopolymers are presented. The best results in the
evaluated area reached the sample H1, which contents the highest
portion of particle under 20μm (100% of GFA). The interdependence
of individual tested properties was confirmed for geopolymer
mixtures corresponding to those in the cement based mixtures: higher
is portion of fine particles < 20μm, higher is strength, density and
lower are sorption properties. The compressive strength as well as
sorption parameters of the geopolymer can be reasonably controlled
by grinding process and also ensured by the higher share of fine
particle (to 20μm) in total mass of the material.
Abstract: The efficiency of the actuation system of exoskeletons
and active orthoses for lower limbs is a significant aspect of the
design of such devices because it affects their efficacy. The F-IVT is
an innovative actuation system to power artificial knee joint with
energy recovery capabilities. Its key and non-conventional elements
are a flywheel that acts as a mechanical energy storage system, and
an Infinitely Variable Transmission (IVT). The design of the F-IVT
can be optimized for a certain walking condition, resulting in a heavy
reduction of both the electric energy consumption and of the electric
peak power. In this work, by means of simulations of level ground
walking at different speeds, it is demonstrated that the F-IVT is still
an advantageous actuator which permits to save energy consumption
and to downsize the electric motor even when it does not work in
nominal conditions.
Abstract: The purpose of the paper is to examine the most
critical and important factor which will affect the implementation of
Total Quality Management (TQM) in the construction industry in the
United Arab Emirates. It also examines the most effected Project
outcome from implementing TQM. A framework was also proposed
depending on the literature studies. The method used in this paper is a
quantitative study. A survey with a sample of 60 respondents was
created and distributed in a construction company in Abu Dhabi,
which includes 15 questions to examine the most critical factor that
will affect the implementation of TQM in addition to the most
effected project outcome from implementing TQM. The survey
showed that management commitment is the most important factor in
implementing TQM in a construction company. Also it showed that
Project cost is most effected outcome from the implementation of
TQM.
Management commitment is very important for implementing
TQM in any company. If the management loose interest in quality
then everyone in the organization will do so. The success of TQM
will depend mostly on the top of the pyramid. Also cost is reduced
and money is saved when the project team implement TQM. While if
no quality measures are present within the team, the project will
suffer a commercial failure.
Based on literature, more factors can be examined and added to
the model. In addition, more construction companies could be
surveyed in order to obtain more accurate results. Also this study
could be conducted outside the United Arab Emirates for further
enchantment.
Abstract: This study is about the structural transformations of
aluminium examining with the Dynamic Mechanical Thermal
Analyzer (DMTA). It is a faster and simpler measuring method to
make consequence about the metal’s structural transformations. The
device measures the changing of the mechanical characteristics
depending on the heating rate, and concludes certain transformations.
This measuring method fast and shows clean-cut results comparing
the conventional ways.
Applying polymer measuring devices for metal investigations is
not widespread method. One of the adaptable ways is shown in this
study. The article compares the results of the small specimen test and
the DMTA method, considering the temperature and the forming
dependence of recrystallization temperature.
Abstract: Availability of different genetic tests after completion
of Human Genome Project increases the physicians’ responsibility to
keep themselves update on the potential implementation of these
genetic tests in their daily practice. However, due to numbers of
barriers, still many of physicians are not either aware of these tests or
are not willing to offer or refer their patients for genetic tests. This
study was conducted an anonymous, cross-sectional, mailed-based
survey to develop a primary data of Malaysian physicians’ level of
knowledge and perception of gene profiling. Questionnaire had 29
questions. Total scores on selected questions were used to assess the
level of knowledge. The highest possible score was 11. Descriptive
statistics, one way ANOVA and chi-squared test was used for
statistical analysis. Sixty three completed questionnaires were
returned by 27 general practitioners (GPs) and 36 medical specialists.
Responders’ age ranges from 24 to 55 years old (mean 30.2 ± 6.4).
About 40% of the participants rated themselves as having poor level
of knowledge in genetics in general whilst 60% believed that they
have fair level of knowledge; however, almost half (46%) of the
respondents felt that they were not knowledgeable about available
genetic tests. A majority (94%) of the responders were not aware of
any lab or company which is offering gene profiling services in
Malaysia. Only 4% of participants were aware of using gene profiling
for detection of dosage of some drugs. Respondents perceived greater
utility of gene profiling for breast cancer (38%) compared to the
colorectal familial cancer (3%). The score of knowledge ranged from
2 to 8 (mean 4.38 ± 1.67). Non- significant differences between score
of knowledge of GPs and specialists were observed, with score of
4.19 and 4.58 respectively. There was no significant association
between any demographic factors and level of knowledge. However,
those who graduated between years 2001 to 2005 had higher level of
knowledge. Overall, 83% of participants showed relatively high level
of perception on value of gene profiling to detect patient’s risk of
disease. However, low perception was observed for both statements
of using gene profiling for general population in order to alter their
lifestyle (25%) as well as having the full sequence of a patient
genome for the purpose of determining a patient’s best match for
treatment (18%). The lack of clinical guidelines, limited provider
knowledge and awareness, lack of time and resources to educate
patients, lack of evidence-based clinical information and cost of tests
were the most barriers of ordering gene profiling mentioned by
physicians. In conclusion Malaysian physicians who participate in
this study had mediocre level of knowledge and awareness in gene
profiling. The low exposure to the genetic questions and problems
might be a key predictor of lack of awareness and knowledge on
available genetic tests. Educational and training workshop might be useful in helping Malaysian physicians incorporate genetic profiling
into practice for eligible patients.
Abstract: The following paper presents the results of a study
aimed at achieving a better understanding of the psychological
readiness for mobile learning (m-learning) among Saudi students,
while also evaluating m-learning readiness as a whole in Saudi
Arabia - a topic that has not yet received adequate attention from
researchers. Data was acquired via a questionnaire administered to
131 Saudi students at UK universities, in July 2013. The study
confirmed that students are confident about using mobile devices in
their daily lives, and that they would welcome more opportunities for
mobile learning. The findings also indicated that Saudi higher
education students are very familiar with, and psychologically ready
for, m-learning.
Abstract: The main objective of incorporating natural fibers such as Henequen microfibers (NF) into the High Density Polyethylene (HDPE) polymer matrix is to reduce the cost and to enhance the mechanical as well as other properties. The Henequen microfibers were chopped manually to 5-7mm in length and added into the polymer matrix at the optimized concentration of 8 wt %. In order to facilitate the link between Henequen microfibers (NF) and HDPE matrix, coupling agent such as Glycidoxy (Epoxy) Functional Methoxy Silane (GPTS) at various concentrations from 0.1%, 0.3%, 0.5%, 0.7%, 0.9% and 1% by weight to the total fibers were added. The tensile strength of the composite increased marginally while % elongation at break of the composites decreased with increase in silane loading by wt %. Tensile modulus and stiffness observed increased at 0.9 wt % GPTS loading. Flexural as well as impact strength of the composite decreased with increase in GPTS loading by weight %. Dielectric strength of the composite also found increased marginally up to 0.5wt % silane loading and thereafter remained constant.
Abstract: The use of energy dissipation systems for seismic applications has increased worldwide, thus it is necessary to develop practical and modern criteria for their optimal design. Here, a direct displacement-based seismic design approach for frame buildings with hysteretic energy dissipation systems (HEDS) is applied. The building is constituted by two individual structural systems consisting of: 1) a main elastic structural frame designed for service loads; and 2) a secondary system, corresponding to the HEDS, that controls the effects of lateral loads. The procedure implies to control two design parameters: a) the stiffness ratio (α=Kframe/Ktotal system), and b) the strength ratio (γ=Vdamper/Vtotal system). The proposed damage-controlled approach contributes to the design of a more sustainable and resilient building because the structural damage is concentrated on the HEDS. The reduction of the design displacement spectrum is done by means of a damping factor (recently published) for elastic structural systems with HEDS, located in Mexico City. Two limit states are verified: serviceability and near collapse. Instead of the traditional trial-error approach, a procedure that allows the designer to establish the preliminary sizes of the structural elements of both systems is proposed. The design methodology is applied to an 8-story steel building with buckling restrained braces, located in soft soil of Mexico City. With the aim of choosing the optimal design parameters, a parametric study is developed considering different values of હ and . The simplified methodology is for preliminary sizing, design, and evaluation of the effectiveness of HEDS, and it constitutes a modern and practical tool that enables the structural designer to select the best design parameters.
Abstract: The paper shows the necessity of farm diversification
in accordance with the current trends in agricultural sector of
Georgia. The possibilities for the diversification and the
corresponding economic policy are suggested.
The causes that hinder diversification of farms are revealed,
possibilities of diversification are identified and the ability of
increasing employment through diversification is proved. Index of
harvest diversification is calculated based on the areas used for
cereals and legumes, potatoes and vegetables and other food crops.
Crop and livestock production indexes are analyzed; correlation
between crop capacity index and value added per worker and per
hectare is studied.
Based on the research farm diversification strategies and priorities
of corresponding economic policy are presented. Based on the
conclusions relevant recommendations are suggested.
Abstract: Lignocellolusic material is a substance that is resistant to be degraded by microorganisms or hydrolysis enzymes. To be used as materials for biofuel production, it needs pretreatment process to improve efficiency of hydrolysis. In this work, chemical pretreatments on rice straw using three diluted organic acids, including acetic acid, citric acid, oxalic acid, were optimized. Using Response Surface Methodology (RSM), the effect of three pretreatment parameters, acid concentration, treatment time, and reaction temperature, on pretreatment efficiency were statistically evaluated. The results indicated that dilute oxalic acid pretreatment led to the highest enhancement of enzymatic saccharification by commercial cellulase and yielded sugar up to 10.67 mg/ml when using 5.04% oxalic acid at 137.11 oC for 30.01 min. Compared to other acid pretreatment by acetic acid, citric acid, and hydrochloric acid, the maximum sugar yields are 7.07, 6.30, and 8.53 mg/ml, respectively. Here, it was demonstrated that organic acids can be used for pretreatment of lignocellulosic materials to enhance of hydrolysis process, which could be integrated to other applications for various biorefinery processes.
Abstract: This paper deals with the theoretical and numerical
investigation of magneto hydrodynamic boundary layer flow of a
nanofluid past a wedge shaped wick in heat pipe used for the cooling
of electronic components and different type of machines. To
incorporate the effect of nanoparticle diameter, concentration of
nanoparticles in the pure fluid, nanothermal layer formed around the
nanoparticle and Brownian motion of nanoparticles etc., appropriate
models are used for the effective thermal and physical properties of
nanofluids. To model the rotation of nanoparticles inside the base
fluid, microfluidics theory is used. In this investigation ethylene
glycol (EG) based nanofluids, are taken into account. The non-linear
equations governing the flow and heat transfer are solved by using a
very effective particle swarm optimization technique along with
Runge-Kutta method. The values of heat transfer coefficient are
found for different parameters involved in the formulation viz.
nanoparticle concentration, nanoparticle size, magnetic field and
wedge angle etc. It is found that, the wedge angle, presence of
magnetic field, nanoparticle size and nanoparticle concentration etc.
have prominent effects on fluid flow and heat transfer characteristics
for the considered configuration.
Abstract: In emerging economies, recycling is an opportunity
for the cities to increase the lifespan of sanitary landfills, reduce the
costs of the solid waste management, decrease the environmental
problems of the waste treatment through reincorporate waste in the
productive cycle and protect and develop people’s livelihoods of
informal waste pickers. However, few studies have analysed the
possibilities and strategies to integrate formal and informal sectors in
the solid waste management for the benefit of both. This study seek
to make a strength, weakness, opportunity, and threat (SWOT)
analysis in three recycling associations of Bogotá with the aim to
understand and determine the situation of recycling from perspective
of informal sector in its transition to enter as authorized waste
providers. Data used in the analysis are derived from multiple
strategies such as literature review, the Bogota’s recycling database,
focus group meetings, governmental reports, national laws and
regulations and specific interviews with key stakeholders. Results of
this study show as the main stakeholders of formal and informal
sector of waste management can identify the internal and internal
conditions of recycling in Bogotá. Several strategies were designed
based on the SWOTs determined, could be useful for Bogotá to
advance and promote recycling as a key strategy for integrated
sustainable waste management in the city.
Abstract: In this article, the antibiogram and heavy metal
resistance profile of the bacteria isolated from total 34 studied
animals (Pelophylax ridibundus = 12; Mauremys rivulata = 14;
Natrix natrix = 8) captured around the Biga Stream, are described.
There was no database information on antibiogram and heavy metal
resistance profile of bacteria from these area’s amphibians and
reptiles.
A total of 200 bacteria were successfully isolated from cloaca and
oral samples of the aquatic amphibians and reptiles as well as from
the water sample. According to Jaccard’s similarity index, the degree
of similarity in the bacterial flora was quite high among the
amphibian and reptile species under examination, whereas it was
different from the bacterial diversity in the water sample. The most
frequent isolates were A. hydrophila (31.5%), B. pseudomallei
(8.5%), and C. freundii (7%). The total numbers of bacteria obtained
were as follows: 45 in P. ridibundus, 45 in N. natrix 30 in M.
rivulata, and 80 in the water sample. The result showed that
cefmetazole was the most effective antibiotic to control the bacteria
isolated in this study and that approximately 93.33% of the bacterial
isolates were sensitive to this antibiotic. The multiple antibiotic
resistances (MAR) index indicated that P. ridibundus (0.95) > N.
natrix (0.89) > M. rivulata (0.39). Furthermore, all the tested heavy
metals (Pb+2, Cu+2, Cr+3, and Mn+2) inhibit the growth of the bacterial
isolates at different rates. Therefore, it indicated that the water source
of the animals was contaminated with both antibiotic residues and
heavy metals.