Abstract: Properties of Portland cement mixtures with various
fractions of metakaolin were studied. 10% of Portland cement CEM I
42.5 R was replaced by different fractions of high reactivity
metakaolin with defined chemical and mineralogical properties.
Various fractions of metakaolin were prepared by jet mill classifying
system. There is a clear trend between fineness of metakaolin and
hydration heat development. Due to metakaolin presence in mixtures
the compressive strength development of mortars is rather slower for
coarser fractions but 28-day flexural strengths are improved for all
fractions of metakaoline used in mixtures compared to reference
sample of pure Portland cement. Yield point, plastic viscosity and
adhesion of fresh pastes are considerably influenced by fineness of
metakaolin used in cement pastes.
Abstract: The objective of countercyclical capital buffer is to
encourage banks to build up buffers in good times that can be drawn
down in bad times. The aim of the report is to assess such decisions
by banks derived from three approaches. The approaches are the
aggregate credit-to-GDP ratio, credit growth as well as banking
sector profits. The approaches are implemented for Estonia, Latvia
and Lithuania for the time period 2000-2012. The report compares
three approaches and analyses their relevance to the Baltic States by
testing the correlation between a growth in studied variables and a
growth of corresponding gaps. Methods used in the empirical part of
the report are econometric analysis as well as economic analysis,
development indicators, relative and absolute indicators and other
methods. The research outcome is a cross-Baltic comparison of two
alternative approaches to establish or release a countercyclical capital
buffer by banks and their implications for each Baltic country.
Abstract: The paper presents a thermodynamic cycle analysis
for three turboshaft engines. The first cycle is a Brayton cycle,
describing the evolution of a classical turboshaft, based on the
Klimov TV2 engine. The other four cycles aim at approaching an
Ericsson cycle, by replacing the Brayton cycle adiabatic expansion in
the turbine by quasi-isothermal expansion. The maximum quasi-
Ericsson cycles temperature is set to a lower value than the maximum
Brayton cycle temperature, equal to the Brayton cycle power turbine
inlet temperature, in order to decrease the engine NOx emissions.
Also, the power/expansion ratio distribution over the stages of the gas
generator turbine is maintained the same. In two of the considered
quasi-Ericsson cycles, the efficiencies of the gas generator turbine, as
well as the power/expansion ratio distribution over the stages of the
gas generator turbine are maintained the same as for the reference
case, while for the other two cases, the efficiencies are increased in
order to obtain the same shaft power as in the reference case. For the
two cases respecting the first condition, both the shaft power and the
thermodynamic efficiency of the engine decrease, while for the other
two, the power and efficiency are maintained, as a result of assuming
new, more efficient gas generator turbines.
Abstract: In this paper, a new design of spherical robotic system
based on the concepts of gimbal structure and gyro dynamics is
presented. Robots equipped with multiple wheels and complex
steering mechanics may increase the weight and degrade the energy
transmission efficiency. In addition, the wheeled and legged robots are
relatively vulnerable to lateral impact and lack of lateral mobility.
Therefore, the proposed robotic design uses a spherical shell as the
main body for ground locomotion, instead of using wheel devices.
Three spherical shells are structured in a similar way to a gimbal
device and rotate like a gyro system. The design and mechanism of the
proposed robotic system is introduced. In addition, preliminary results
of the dynamic model based on the principles of planar rigid body
kinematics and Lagrangian equation are included. Simulation results
and rig construction are presented to verify the concepts.
Abstract: The objectives of the study were to determine the
marketing mix factors that influencing tourist’s destination decision
making for cultural tourism in the Chonburi province. Both
quantitative and qualitative data were applied in this study. The
samples of 400 cases for quantitative analysis were tourists (both
Thai and foreign) who were interested in cultural tourism in the
Chonburi province, and traveled to cultural sites in Chonburi and 14
representatives from provincial tourism committee of Chonburi and
local tourism experts. Statistics utilized in this research included
frequency, percentage, mean, standard deviation, and multiple
regression analysis. The study found that Thai and foreign tourists
are influenced by different important marketing mix factors. The
important factors for Thai respondents were physical evidence, price,
people, and place at high importance level. For foreign respondents,
physical evidence, price, people, and process were high importance
level, whereas, product, place and promotion were moderate
importance level.
Abstract: The Algeria by its location offers a rich and diverse
vegetation. A large number of aromatic and medicinal plants grow
spontaneously. The interest in these plants has continued to grow in
recent years. Their particular properties due to the essential oil
fraction can be utilized to treat microbial infections. To this end, and
in the context of the valuation of the Algerian flora, we became
interested in the species of the family Lamiaceae which is one of the
most used as a global source of spices. The plant on which we have
based our choice is a species of sage "Salvia officinalis" from the
Isser localized region within the province of Boumerdes. This work
focuses on the study of the antimicrobial activity of essential oil
extracted from the leaves of Salvia officinalis. The extraction is
carried out by essential oil hydrodistillation and reveals a yield of
1.06℅. The study of the antimicrobial activity of the essential oil by
the method of at aromatogramme shown that Gram positive bacteria
are most susceptible (Staphylococcus aureus and Bacillus subtilis)
with a strong inhibition of growth. The yeast Candida albicans
fungus Aspergillus niger and have shown moderately sensitive.
Abstract: Innovation plays an important role in economic
growth and development. Evolutionary economics has entrepreneurs
at the centre of the innovation system, but includes all other
participants as contributors to the performance of the innovation
system. Education and training institutions, one of the participants in
the innovation system, contributes in different ways to human capital.
The gap in literature on the competence building as part of human
capital in the analysis of innovation systems is addressed in this
paper. The Mpumalanga Province of South Africa is used as a case
study. It was found that the absence of a university, the level of
education, the quality and performance in the education sector and
the condition of the education infrastructure have not been conducive
to learning.
Abstract: Electronic Word-Of-Mouth (eWOM) communities
represent today an important source of information in which more
and more customers base their purchasing decisions. They include
thousands of reviews concerning very different products and services
posted by many individuals geographically distributed all over the
world. Due to their massive audience, eWOM communities can help
users to find the product they are looking for even if they are less
popular or rare. This is known as the long tail effect, which leads to a
larger number of lower-selling niche products. This paper analyzes
the long tail effect in a well-known eWOM community and defines a
tool for finding niche products unavailable through conventional
channels.
Abstract: The heavy metal pollution degree in the soils around
the Zangezur copper and molybdenum combine in Syunik Marz,
Armenia was assessed. The results of the study showed that heavy
metal pollution degree in the soils mainly decreased with increasing
distance from the open mine and the ore enrichment combine which
indicated that the open mine and the ore enrichment combine were
the main sources of heavy metal pollution. The only exception was
observed in the northern part of the open mine where pollution
degree in the sites (along the open mine) situated 600 meters far from
the mine was higher than that in the sites located 300 meters far from
the mine. This can be explained by the characteristics of relief and air
currents as well as the weak vegetation cover of these sites and the
characteristics of soil structure. According to geo-accumulation index
(I-geo), contamination factor (Cf), contamination degree (Cd) and
pollution load index (PLI) values, the pollution degree in the soils
around the open mine and the ore enrichment combine was higher
than that in the soils around the tailing dumps which was due to the
proper and accurate operation of the Artsvanik tailing damp and the
recultivation of the Voghji tailing dump.
The high Cu and Mo pollution of the soils was conditioned by the
character of industrial activities, the moving direction of air currents
as well as the physicochemical peculiarities of the soils.
Abstract: The explosion of the World Wide Web and the
electronic trend of university teaching have transformed the learning
style to become more learner-centered, which has popularized the
digital delivery of mediated lectures as an alternative or an adjunct to
traditional lectures. Despite its potential and popularity, virtual
lectures have not been adopted yet in Jordanian universities. This
research aimed to fill this gap by studying the factors that influence
students’ willingness to accept virtual lectures in one Jordanian
University. A quantitative approach was followed, by obtaining 216
survey responses and statistically applying the UTAUT model with
some modifications. Results revealed that performance expectancy,
effort expectancy, social influences, and self-efficacy could
significantly influence students’ attitudes towards virtual lectures.
Additionally, Facilitating conditions and attitudes towards virtual
lectures were found with significant influence on students’ intention
to take virtual lectures. Research implications and future work were
specified afterwards.
Abstract: In this study, the Compressive strength of concretes
made with Ground Granulated Blast furnace Slag (GGBS),
Pulverised Fuel Ash (PFA), Rice Husk Ash (RHA) and Waste Glass
Powder (WGP) after they were exposed 7800C (exposure duration of
around 60 minutes) and then allowed to cool down gradually in the
furnace for about 280 minutes at water binder ratio of 0.50 was
investigated. GGBS, PFA, RHA and WGP were used to replace up to
20% Portland cement in the control concrete. Test for the
determination of workability, compressive strength and tensile
splitting strength of the concretes were carried out and the results
were compared with control concrete. The test results showed that the
compressive strength decreased by an average of around 30% after
the concretes were exposed to the heating and cooling scenario.
Abstract: The thermal control in many systems is widely
accomplished applying mixed convection process due to its low cost,
reliability and easy maintenance. Typical applications include the
aircraft electronic equipment, rotating-disc heat exchangers, turbo
machinery, and nuclear reactors, etc. Natural convection in an inclined
square enclosure heated via wall heater has been studied numerically.
Finite volume method is used for solving momentum and energy
equations in the form of stream function–vorticity. The right and left
walls are kept at a constant temperature, while the other parts are
adiabatic. The range of the inclination angle covers a whole revolution.
The method is validated for a vertical cavity. A general power law
dependence of the Nusselt number with respect to the Rayleigh
number with the coefficient and exponent as functions of the
inclination angle is presented. For a fixed Rayleigh number, the
inclination angle increases or decreases is found.
Abstract: Catalytic combustion of methane is imperative due to
stability of methane at low temperature. Methane (CH4), therefore,
remains unconverted in vehicle exhausts thereby causing greenhouse
gas GHG emission problem. In this study, heterogeneous catalysts of
palladium with bio-char (2 wt% Pd/Bc) and Al2O3 (2wt% Pd/ Al2O3)
supports were prepared by incipient wetness impregnation and then
subsequently tested for catalytic combustion of CH4. Support-porous
heterogeneous catalytic combustion (HCC) material were selected
based on factors such as surface area, porosity, thermal stability,
thermal conductivity, reactivity with reactants or products, chemical
stability, catalytic activity, and catalyst life. Sustainable and
renewable support-material of bio-mass char derived from palm shell
waste material was compared with those from the conventional
support-porous materials. Kinetic rate of reaction was determined for
combustion of methane on Palladium (Pd) based catalyst with Al2O3
support and bio-char (Bc). Material characterization was done using
TGA, SEM, and BET surface area. The performance test was
accomplished using tubular quartz reactor with gas mixture ratio of
3% methane and 97% air. The methane porous-HCC conversion was
carried out using online gas analyzer connected to the reactor that
performed porous-HCC. BET surface area for prepared 2 wt% Pd/Bc
is smaller than prepared 2wt% Pd/ Al2O3 due to its low porosity
between particles. The order of catalyst activity based on kinetic rate
on reaction of catalysts in low temperature was 2wt%
Pd/Bc>calcined 2wt% Pd/ Al2O3> 2wt% Pd/ Al2O3>calcined 2wt%
Pd/Bc. Hence agro waste material can successfully be utilized as an
inexpensive catalyst support material for enhanced CH4 catalytic
combustion.
Abstract: Modern Portfolio Theory (MPT) according to
Markowitz states that investors form mean-variance efficient
portfolios which maximizes their utility. Markowitz proposed the
standard deviation as a simple measure for portfolio risk and the
lower semi-variance as the only risk measure of interest to rational
investors. This paper uses a third volatility estimator based on
intraday data and compares three efficient frontiers on the Croatian
Stock Market. The results show that range-based volatility estimator
outperforms both mean-variance and lower semi-variance model.
Abstract: This study aimed to examine the management and
development of forest tourism Kamchanoad. Ban Dung, Udon Thani
sustainability. Data were collected by means of qualitative research
including in-depth interviews, semi- structured, and then the data
were summarized and discussed in accordance with the objectives.
And make a presentation in the form of lectures. The target
population for the study consisted of 16 people, including
representatives from government agencies, community leaders and
the community. The results showed that Guidelines for the
Management and Development of Forest Tourism Kamchanoad
include management of buildings and infrastructure such as roads,
water, electricity, toilets. Other developments are the establishment
of a service center that provides information and resources to
facilitate tourists.; nature trails and informative signage to educate
visitors on the path to the jungle Kamchanoad; forest activities for
tourists who are interested only in occasional educational activities
such as vegetation, etc.; disseminating information on various aspects
of tourism through various channels in both Thailand and English, as
well as a web site to encourage community involvement in the
planning and management of tourism together with the care and
preservation of natural resources and preserving the local cultural
tourist area of Kamchanoad.
Abstract: To determine the potential of a low cost Irish
engineered timber product to replace high cost solid timber for use in
bending active structures such as gridshells a single Irish engineered
timber product in the form of orientated strand board (OSB) was
selected. A comparative study of OSB and solid timber was carried
out to determine the optimum properties that make a material suitable
for use in gridshells. Three parameters were identified to be relevant
in the selection of a material for gridshells. These three parameters
are the strength to stiffness ratio, the flexural stiffness of
commercially available sections, and the variability of material and
section properties. It is shown that when comparing OSB against
solid timber, OSB is a more suitable material for use in gridshells that
are at the smaller end of the scale and that have tight radii of
curvature. Typically, for solid timber materials, stiffness is used as an
indicator for strength and engineered timber is no different. Thus, low
flexural stiffness would mean low flexural strength. However, when
it comes to bending active gridshells, OSB offers a significant
advantage. By the addition of multiple layers, an increased section
size is created, thus endowing the structure with higher stiffness and
higher strength from initial low stiffness and low strength materials
while still maintaining tight radii of curvature. This allows OSB to
compete with solid timber on large scale gridshells. Additionally, a
preliminary sustainability study using a set of sustainability indicators
was carried out to determine the relative sustainability of building a
large-scale gridshell in Ireland with a primary focus on economic
viability but a mention is also given to social and environmental
aspects. For this, the Savill garden gridshell in the UK was used as
the functional unit with the sustainability of the structural roof
skeleton constructed from UK larch solid timber being compared
with the same structure using Irish OSB. Albeit that the advantages of
using commercially available OSB in a bending active gridshell are
marginal and limited to specific gridshell applications, further study
into an optimised engineered timber product is merited.
Abstract: Array-based gene expression analysis is a powerful
tool to profile expression of genes and to generate information on
therapeutic effects of new anti-cancer compounds. Anti-apoptotic
effect of thymoquinone was studied in MCF7 breast cancer cell line
using gene expression profiling with cDNA microarray. The purity
and yield of RNA samples were determined using RNeasyPlus Mini
kit. The Agilent RNA 6000 NanoLabChip kit evaluated the quantity
of the RNA samples. AffinityScript RT oligo-dT promoter primer
was used to generate cDNA strands. T7 RNA polymerase was used to
convert cDNA to cRNA. The cRNA samples and human universal
reference RNA were labelled with Cy-3-CTP and Cy-5-CTP,
respectively. Feature Extraction and GeneSpring softwares analysed
the data. The single experiment analysis revealed involvement of 64
pathways with up-regulated genes and 78 pathways with downregulated
genes. The MAPK and p38-MAPK pathways were
inhibited due to the up-regulation of PTPRR gene. The inhibition of
p38-MAPK suggested up-regulation of TGF-ß pathway. Inhibition of
p38-MAPK caused up-regulation of TP53 and down-regulation of
Bcl2 genes indicating involvement of intrinsic apoptotic pathway.
Down-regulation of CARD16 gene as an adaptor molecule regulated
CASP1 and suggested necrosis-like programmed cell death and
involvement of caspase in apoptosis. Furthermore, down-regulation
of GPCR, EGF-EGFR signalling pathways suggested reduction of
ER. Involvement of AhR pathway which control cytochrome P450
and glucuronidation pathways showed metabolism of Thymoquinone.
The findings showed differential expression of several genes in
apoptosis pathways with thymoquinone treatment in estrogen
receptor-positive breast cancer cells.
Abstract: We assessed the ecology of the organic and mineral soil
layers of laurel-leaved (BB-1) and Cryptomeria japonica (BB-2 and Pw)
forests in the Kasugayama Hill Primeval Forest (Nara, Japan). The soil
respiration rate was higher in the deeper horizons (F and H) of organic
layers than in those of mineral soil layers, suggesting organic layers
may be where active microbial metabolism occurs. Respiration rates in
the soil of BB-1, BB-2 and Pw forests were closely similar at 5 and 10°C.
However, the soil respiration rate increased in proportion to
temperatures of 15°C or above. We therefore consider the activity of
soil microorganisms to markedly decrease at temperatures below 10°C.
At a temperature of 15°C or above, the soil respiration rate in the BB-1
organic layers was higher than in those of the BB-2 and Pw organic
layers, due to differences in forest vegetation that appeared to
influence several salient soil properties, particularly pH and the carbon
(C) and nitrogen (N) content of the F and H horizons.
Abstract: Object-oriented modeling is spreading in current
simulation of physiological systems through the use of the individual
components of the model and its interconnections to define the
underlying dynamic equations. In this paper we describe the use of
both the SIMSCAPE and MODELICA simulation environments in
the object-oriented modeling of the closed loop cardiovascular
system. The performance of the controlled system was analyzed by
simulation in light of the existing hypothesis and validation tests
previously performed with physiological data. The described
approach represents a valuable tool in the teaching of physiology for
graduate medical students.
Abstract: In the past few decades, the field of chemistry
education has grown tremendously and researches indicated that after
traditional chemistry instruction students often lacked deep
conceptual understanding and failed to integrate their ideas into
coherent conceptual framework. For several concepts in chemistry,
students at all levels have demonstrated difficulty in changing their
initial perceptions. Their perceptions are most often wrong and don't
agree with correct scientific concepts. This study explored the
effectiveness of intervention discussion sections for a college general
chemistry course designed to apply research on students
preconceptions, knowledge integration and student explanation.
Three interventions discussions lasting three hours on bond energy
and spontaneity were done tested and intervention (treatment)
students’ performances were compared with that of control group
which did not use the experimental pedagogy. Results indicated that
this instruction which was capable of identifying students'
misconceptions, initial conceptions and integrating those ideas into
class discussion led to enhanced conceptual understanding and better
achievement for the experimental group.