Abstract: Problems insulation of building structures is often
closely connected with the problem of moisture remediation. In the
case of historic buildings or if only part of the redevelopment of
envelope of structures, it is not possible to apply the classical external
thermal insulation composite systems. This application is mostly
effective thermal insulation plasters with high porosity and controlled
capillary properties which assures improvement of thermal properties
construction, its diffusion openness towards the external environment
and suitable treatment capillary properties of preventing the
penetration of liquid moisture and salts thereof toward the outer
surface of the structure.
With respect to the current trend of reducing the energy
consumption of building structures and reduce the production of CO2
is necessary to develop capillary-active materials characterized by
their low density, low thermal conductivity while maintaining good
mechanical properties. The aim of researchers at the Faculty of Civil
Engineering, Brno University of Technology is the development and
study of hygrothermal behaviour of optimal materials for thermal
insulation and rehabilitation of building structures with the possible
use of alternative, less energy demanding binders in comparison with
conventional, frequently used binder, which represents cement.
The paper describes the evaluation of research activities aimed at
the development of thermal insulation and repair materials using
lightweight aggregate and alternative binders such as metakaolin and
finely ground fly ash.
Abstract: The paper deals with possibilities of interpretation of
iron ore reducibility tests. It presents a mathematical model
developed at Centre ENET, VŠB – Technical University of Ostrava,
Czech Republic for an evaluation of metallurgical material of blast
furnace feedstock such as iron ore, sinter or pellets. According to the
data from the test, the model predicts its usage in blast furnace
technology and its effects on production parameters of shaft
aggregate. At the beginning, the paper sums up the general concept
and experience in mathematical modelling of iron ore reduction. It
presents basic equation for the calculation and the main parts of the
developed model. In the experimental part, there is an example of
usage of the mathematical model. The paper describes the usage of
data for some predictive calculation. There are presented material,
method of carried test of iron ore reducibility. Then there are
graphically interpreted effects of used material on carbon
consumption, rate of direct reduction and the whole reduction
process.
Abstract: The problem of toughening in brittle materials
reinforced by fibers is complex, involving all of the mechanical
properties of fibers, matrix and the fiber/matrix interface, as well as
the geometry of the fiber. Development of new numerical methods
appropriate to toughening simulation and analysis is necessary. In
this work, we have performed simulations and analysis of toughening
in brittle matrix reinforced by randomly distributed fibers by means
of the discrete elements method. At first, we put forward a
mechanical model of toughening contributed by random fibers. Then
with a numerical program, we investigated the stress, damage and
bridging force in the composite material when a crack appeared in the
brittle matrix. From the results obtained, we conclude that: (i) fibers
of high strength and low elasticity modulus are beneficial to
toughening; (ii) fibers of relatively high elastic modulus compared to
the matrix may result in substantial matrix damage due to spalling
effect; (iii) employment of high-strength synthetic fibers is a good
option for toughening. We expect that the combination of the discrete
element method (DEM) with the finite element method (FEM) can
increase the versatility and efficiency of the software developed. The
present work can guide the design of ceramic composites of high
performance through the optimization of the parameters.
Abstract: In this paper, we will give a cryptographic application
over the integral closure O_Lof sextic extension L, namely L is an
extension of Q of degree 6 in the form Q(a,b), which is a rational
quadratic and monogenic extension over a pure monogenic cubic
subfield K generated by a who is a root of monic irreducible
polynomial of degree 2 andb is a root of irreducible polynomial of
degree 3.
Abstract: Co-crystal is believed to improve the solubility and
dissolution rates and thus, enhanced the bioavailability of poor water
soluble drugs particularly during the oral route of administration.
With the existing of poorly soluble drugs in pharmaceutical industry,
the screening of co-crystal formation using carbamazepine (CBZ) as
a model drug compound with dicarboxylic acids co-crystal formers
(CCF) namely fumaric (FA) and succinic (SA) acids in ethanol has
been studied. The co-crystal formations were studied by varying the
mol ratio values of CCF to CBZ to access the effect of CCF
concentration on the formation of the co-crystal. Solvent evaporation,
slurry and cooling crystallization which representing the solution
based method co-crystal screening were used. Based on the
differential scanning calorimetry (DSC) analysis, the melting point of
CBZ-SA in different ratio was in the range between 188oC-189oC.
For CBZ-FA form A and CBZ-FA form B the melting point in
different ratio were in the range of 174oC-175oC and 185oC-186oC
respectively. The product crystal from the screening was also
characterized using X-ray powder diffraction (XRPD). The XRPD
pattern profile analysis has shown that the CBZ co-crystals with FA
and SA were successfully formed for all ratios studied. The findings
revealed that CBZ-FA co-crystal were formed in two different
polymorphs. It was found that CBZ-FA form A and form B were
formed from evaporation and slurry crystallization methods
respectively. On the other hand, in cooling crystallization method,
CBZ-FA form A was formed at lower mol ratio of CCF to CBZ and
vice versa. This study disclosed that different methods and mol ratios
during the co-crystal screening can affect the outcome of co-crystal
produced such as polymorphic forms of co-crystal and thereof. Thus,
it was suggested that careful attentions is needed during the screening
since the co-crystal formation is currently one of the promising
approach to be considered in research and development for
pharmaceutical industry to improve the poorly soluble drugs.
Abstract: Incineration of municipal solid waste (MSW) is one of
the key scopes in the global clean energy strategy. A computational
fluid dynamics (CFD) model was established in order to reveal these
features of the combustion process in a fixed porous bed of MSW.
Transporting equations and process rate equations of the waste bed
were modeled and set up to describe the incineration process,
according to the local thermal conditions and waste property
characters. Gas phase turbulence was modeled using k-ε turbulent
model and the particle phase was modeled using the kinetic theory of
granular flow. The heterogeneous reaction rates were determined
using Arrhenius eddy dissipation and the Arrhenius-diffusion
reaction rates. The effects of primary air flow rate and temperature in
the burning process of simulated MSW are investigated
experimentally and numerically. The simulation results in bed are
accordant with experimental data well. The model provides detailed
information on burning processes in the fixed bed, which is otherwise
very difficult to obtain by conventional experimental techniques.
Abstract: Rice husk and kenaf filled with calcium carbonate
(CaCO3) and high density polyethylene (HDPE) composite were
prepared separately using twin-screw extruder at 50rpm. Different
filler loading up to 30 parts of rice husk particulate and kenaf fiber
were mixed with the fixed 30% amount of CaCO3 mineral filler to
produce rice husk/CaCO3/HDPE and kenaf/CaCO3/HDPE hybrid
composites. In this study, the effects of natural fiber for both rice
husk and kenaf in CaCO3/HDPE composite on physical, mechanical
and morphology properties were investigated. Field Emission
Scanning Microscope (FeSEM) was used to investigate the impact
fracture surfaces of the hybrid composite. The property analyses
showed that water absorption increased with the presence of kenaf
and rice husk fillers. Natural fibers in composite significantly
influence water absorption properties due to natural characters of
fibers which contain cellulose, hemicellulose and lignin structures.
The result showed that 10% of additional natural fibers into hybrid
composite had caused decreased flexural strength, however additional
of high natural fiber (>10%) filler loading has proved to increase its
flexural strength.
Abstract: A model was constructed to predict the amount of
solar radiation that will make contact with the surface of the earth in
a given location an hour into the future. This project was supported
by the Southern Company to determine at what specific times during
a given day of the year solar panels could be relied upon to produce
energy in sufficient quantities. Due to their ability as universal
function approximators, an artificial neural network was used to
estimate the nonlinear pattern of solar radiation, which utilized
measurements of weather conditions collected at the Griffin, Georgia
weather station as inputs. A number of network configurations and
training strategies were utilized, though a multilayer perceptron with
a variety of hidden nodes trained with the resilient propagation
algorithm consistently yielded the most accurate predictions. In
addition, a modeled direct normal irradiance field and adjacent
weather station data were used to bolster prediction accuracy. In later
trials, the solar radiation field was preprocessed with a discrete
wavelet transform with the aim of removing noise from the
measurements. The current model provides predictions of solar
radiation with a mean square error of 0.0042, though ongoing efforts
are being made to further improve the model’s accuracy.
Abstract: Rural tourism is usually associated with rural
development because it has strong linkages to rural resources; but it
remains underdeveloped compared to urban tourism. This
underdevelopment of rural tourism serves as a motivation for this
study whose aim is to examine the factors affecting the perceived
satisfaction of rural tourists. The objectives of this study are: to
identify and design theories and models on rural tourism satisfaction,
and to empirically validate these models and theories through a
survey of tourists from the Malealea Lodge which is located in the
Mafeteng District, in the Mountain Kingdom of Lesotho. Data
generated by the collection of questionnaires used by this survey was
analyzed quantitatively using descriptive statistics and correlations in
SPSS after checking the validity and the reliability of the
questionnaire. The main hypothesis behind this study is the
relationship between the demographics of rural tourists, their
motivation, and their satisfaction, as supported by existing literature;
except that motivation is measured in this study according to three
dimensions: push factors, pull factors, and perceived usefulness of
ICTs in the rural tourism experience. Findings from this study
indicate that among the demographics factors, continent of origin and
marital status influence the satisfaction of rural tourists; and their
occupation affects their perceptions on the use of ICTs in rural
tourism. Moreover, only pull factors were found to influence the
satisfaction of rural tourists.
Abstract: This paper describes an Action Research project
which was undertaken to inform professional practice in order to
develop a newly created Centre for Student Success in the specific
context of transnational medical and nursing education in the Middle
East. The objectives were to enhance the academic performance,
persistence, integration and personal and professional development of
a multinational study body, in particular in relation to pre-clinical
medical students, and to establish a comfortable, friendly and
student-driven environment within an Irish medical university
recently established in Bahrain. The outcomes of the project resulted
in the development of a specific student success ‘signature’ for this
particular transnational higher education context.
Abstract: An artificial neural network is a mathematical model
inspired by biological neural networks. There are several kinds of
neural networks and they are widely used in many areas, such as:
prediction, detection, and classification. Meanwhile, in day to day life,
people always have to make many difficult decisions. For example,
the coach of a soccer club has to decide which offensive player
to be selected to play in a certain game. This work describes a
novel Neural Network using a combination of the General Regression
Neural Network and the Probabilistic Neural Networks to help a
soccer coach make an informed decision.
Abstract: This study analyzes the innovative orientation of the
Croatian entrepreneurs. Innovative orientation is represented by the
perceived extent to which an entrepreneur’s product or service or
technology is new, and no other businesses offer the same product.
The sample is extracted from the GEM Croatia Adult Population
Survey dataset for the years 2003-2013. We apply descriptive
statistics, t-test, Chi-square test and logistic regression. Findings
indicate that innovative orientations vary with personal, firm, meso
and macro level variables, and between different stages in
entrepreneurship process. Significant predictors are occupation of the
entrepreneurs, size of the firm and export aspiration for both early
stage and established entrepreneurs. In addition, fear of failure,
expecting to start a new business and seeing an entrepreneurial career
as a desirable choice are predictors of innovative orientation among
early stage entrepreneurs.
Abstract: This paper introduces an original method for
guaranteed estimation of the accuracy for an ensemble of Lipschitz
classifiers. The solution was obtained as a finite closed set of
alternative hypotheses, which contains an object of classification with
probability of not less than the specified value. Thus, the
classification is represented by a set of hypothetical classes. In this
case, the smaller the cardinality of the discrete set of hypothetical
classes is, the higher is the classification accuracy. Experiments have
shown that if cardinality of the classifiers ensemble is increased then
the cardinality of this set of hypothetical classes is reduced. The
problem of the guaranteed estimation of the accuracy for an ensemble
of Lipschitz classifiers is relevant in multichannel classification of
target events in C-OTDR monitoring systems. Results of suggested
approach practical usage to accuracy control in C-OTDR monitoring
systems are present.
Abstract: Applications of the Hausdorff space and its mappings
into tangent spaces are outlined, including their fractal dimensions
and self-similarities. The paper details this theory set up and further
describes virtualizations and atomization of manufacturing processes.
It demonstrates novel concurrency principles that will guide
manufacturing processes and resources configurations. Moreover,
varying levels of details may be produced by up folding and breaking
down of newly introduced generic models. This choice of layered
generic models for units and systems aspects along specific aspects
allows research work in parallel to other disciplines with the same
focus on all levels of detail. More credit and easier access are granted
to outside disciplines for enriching manufacturing grounds. Specific
mappings and the layers give hints for chances for interdisciplinary
outcomes and may highlight more details for interoperability
standards, as already worked on the international level. The new rules
are described, which require additional properties concerning all
involved entities for defining distributed decision cycles, again on the
base of self-similarity. All properties are further detailed and assigned
to a maturity scale, eventually displaying the smartness maturity of a
total shopfloor or a factory. The paper contributes to the intensive
ongoing discussion in the field of intelligent distributed
manufacturing and promotes solid concepts for implementations of
Cyber Physical Systems and the Internet of Things into
manufacturing industry, like industry 4.0, as discussed in German-speaking
countries.
Abstract: In this paper we propose a discrete tracking control of
nonholonomic mobile robots with two degrees of freedom. The
electromechanical model of a mobile robot moving on a horizontal
surface without slipping, with two rear wheels controlled by two
independent DC electric, and one front roal wheel is considered. We
present backstepping design based on the Euler approximate discretetime
model of a continuous-time plant. Theoretical considerations are
verified by numerical simulation.
Abstract: The main goal of this article is to describe the online
flood monitoring and prediction system Floreon+ primarily developed
for the Moravian-Silesian region in the Czech Republic and the basic
process it uses for running automatic rainfall-runoff and
hydrodynamic simulations along with their calibration and
uncertainty modeling. It takes a long time to execute such process
sequentially, which is not acceptable in the online scenario, so the use
of a high performance computing environment is proposed for all
parts of the process to shorten their duration. Finally, a case study on
the Ostravice River catchment is presented that shows actual
durations and their gain from the parallel implementation.
Abstract: This paper shortly describes various types of biomass
and a growing number of facilities utilizing the biomass in the Czech
Republic. The considerable part of this paper deals with energy
parameters of the most frequently used types of biomass and results
of their gasification testing. Sixteen most used "Czech" woody plants
and grasses were selected; raw, element and biochemical analyses
were performed and basic calorimetric values, ash composition, and
ash characteristic temperatures were identified. Later, each biofuel
was tested in a fluidized bed gasifier. The essential part of this paper
provides results of the gasification of selected biomass types.
Operating conditions are described in detail with a focus on
individual fuels properties. Gas composition and impurities content
are also identified. In terms of operating conditions and gas quality,
the essential difference occurred mainly between woody plants and
grasses. The woody plants were evaluated as more suitable fuels for
fluidized bed gasifiers. Testing results significantly help with a
decision-making process regarding suitability of energy plants for
growing and with a selection of optimal biomass-treatment
technology.
Abstract: Modeling and forecasting dynamics of rainfall
occurrences constitute one of the major topics, which have been
largely treated by statisticians, hydrologists, climatologists and many
other groups of scientists. In the same issue, we propose, in the
present paper, a new hybrid method, which combines Extreme
Values and fractal theories. We illustrate the use of our methodology
for transformed Emberger Index series, constructed basing on data
recorded in Oujda (Morocco).
The index is treated at first by Peaks Over Threshold (POT)
approach, to identify excess observations over an optimal threshold u.
In the second step, we consider the resulting excess as a fractal object
included in one dimensional space of time. We identify fractal
dimension by the box counting. We discuss the prospect descriptions
of rainfall data sets under Generalized Pareto Distribution, assured by
Extreme Values Theory (EVT). We show that, despite of the
appropriateness of return periods given by POT approach, the
introduction of fractal dimension provides accurate interpretation
results, which can ameliorate apprehension of rainfall occurrences.
Abstract: This technical contribution treats of a novel approach
to condition-oriented maintenance as elaborated by Collaborative
Research Centre 653 at the Leibniz University in Hanover. The
objective resides in the targeted analysis of information about a
component's lifecycle for maintenance purposes. The information in
question is collected by means of the Collaborative Research Centre's
innovative technologies. This enables preventive maintenance of
components on the basis of their condition. This contribution initially
explains condition-oriented maintenance, before introducing the
Collaborative Research Centre and finally presenting the
methodology for analyzing the information. The current state of
development is described and an outlook provided for expanding the
methodology.
Abstract: The formulated problem of optimization of the
technological process of water treatment for thermal power plants is
considered in this article. The problem is of multiparametric nature.
To optimize the process, namely, reduce the amount of waste water, a
new technology was developed to reuse such water. A mathematical
model of the technology of wastewater reuse was developed.
Optimization parameters were determined. The model consists of a
material balance equation, an equation describing the kinetics of ion
exchange for the non-equilibrium case and an equation for the ion
exchange isotherm. The material balance equation includes a
nonlinear term that depends on the kinetics of ion exchange. A direct
problem of calculating the impurity concentration at the outlet of the
water treatment plant was numerically solved. The direct problem
was approximated by an implicit point-to-point computation
difference scheme. The inverse problem was formulated as relates to
determination of the parameters of the mathematical model of the
water treatment plant operating in non-equilibrium conditions. The
formulated inverse problem was solved. Following the results of
calculation the time of start of the filter regeneration process was
determined, as well as the period of regeneration process and the
amount of regeneration and wash water. Multi-parameter
optimization of water treatment process for thermal power plants
allowed decreasing the amount of wastewater by 15%.