Abstract: The global solved problem is the calculation of the
parameters of ceramic material from a set of destruction tests of
ceramic heads of total hip joint endoprosthesis. The standard way of
calculation of the material parameters consists in carrying out a set of
3 or 4 point bending tests of specimens cut out from parts of the
ceramic material to be analysed. In case of ceramic heads, it is not
possible to cut out specimens of required dimensions because the
heads are too small (if the cut out specimens were smaller than the
normalised ones, the material parameters derived from them would
exhibit higher strength values than those which the given ceramic
material really has). A special destruction device for heads
destruction was designed and the solved local problem is the
modification of this destructive device based on the analysis of
tensile stress in the head for two different values of the depth of the
conical hole in the head. The goal of device modification is a shift of
the location with extreme value of σ1max from the region of head’s
hole bottom to its opening. This modification will increase the
credibility of the obtained material properties of bioceramics, which
will be determined from a set of head destructions using the Weibull
weakest link theory.
Abstract: This research aims to investigate callus induction,
somatic embryogenesis and indirect plant regeneration of Crassula
ovata (Mill.) Druce – the famous ornamental plant. Experiment no.1:
Callus induction was obtained from leaf and stem explants on
Murashige and Skoog (MS) medium supplemented with various plant
growth regulators (PGRs). Effects of different PGRs, plant
regeneration and subsequent plantlet conversion were also assessed.
Indirect plant regeneration was achieved from the callus of stem
explants by the addition of 1.5 mg/L Kinetin (KN) alone. Best shoot
induction was achieved (6.5 shoots/per explant) after 60 days. For
successful rooting, regenerated plantlets were sub-cultured on the
same MS media supplemented with 1.5 mg/L KN alone. The rooted
plantlets were acclimatized and the survival rate was 90%.
Experiment no.2: Results revealed that 0.5 mg/L 2,4-D alone and in
combination with 1.0 mg/L 6-Benzyladenine (BA) gave 89.8% callus
from the stem explants as compared to leaf explants. Callus
proliferation and somatic embryo formation were also evaluated by
‘Double Staining Method’ and different stages of somatic
embryogenesis were revealed by scanning electron microscope. Full
Strength MS medium produced the highest number (49.6%) of
cotyledonary stage somatic embryos (SEs). Mature cotyledonary
stage SEs developed into plantlets after 12 weeks of culture. Wellrooted
plantlets were successfully acclimatized at the survival rate of
85%. Indirectly regenerated plants did not show any detectable
variation in morphological and growth characteristics when
compared with the donor plant.
Abstract: This paper considers the characterization of a complex
electromagnetic environment due to multiple sources of
electromagnetic radiation as a five-dimensional surface which can be
described by a set of several surface sections including: instant EM
field intensity distribution maps at a given frequency and altitude,
instantaneous spectrum at a given location in space and the time
evolution of the electromagnetic field spectrum at a given point in
space. This characterization if done over time can enable the
exposure levels of Radio Frequency Radiation at every point in the
analysis area to be determined and results interpreted based on
comparison of the determined RFR exposure level with the safe
guidelines for general public exposure given by recognized body
such as the International commission on non-ionizing radiation
protection (ICNIRP), Institute of Electrical and Electronic Engineers
(IEEE), the National Radiation Protection Authority (NRPA).
Abstract: In the culture of Thailand, the Yak serve as a mediated
icon representing strength, power, and mystical protection not only
for the Buddha, but for population of worshipers. Originating from
the forests of China, the Yak continues to stand guard at the gates of
Buddhist temples. The Yak represents Thai culture in the hearts of
Thai people. This paper presents a qualitative study regarding the
curious mix of media, culture, and religion that projects the Yak of
Thailand as a larger than life message throughout the political,
cultural, and religious spheres. The gate guardians, or gods as they
are sometimes called, appear throughout the religious temples of
Asian cultures. However, the Asian cultures demonstrate differences
in artistic renditions (or presentations) of such sentinels. Thailand
gate guards (the Yak) stand in front of many Buddhist temples, and
these iconic figures display unique features with varied symbolic
significance. The temple (or wat), plays a vital role in every
community; and, for many people, Thailand’s temples are the
country’s most endearing sights. The authors applied folknography as
a methodology to illustrate the importance of the Thai Yak in serving
as meaningful icons that transcend not only time, but the culture,
religion, and mass media. The Yak represents mythical, religious,
artistic, cultural, and militaristic significance for the Thai people.
Data collection included interviews, focus groups, and natural
observations. This paper summarizes the perceptions of the Thai
people concerning their gate sentries and the relationship,
communication, connection, and the enduring respect that Thai
people hold for their guardians of the gates.
Abstract: Different strategies and tools are available at the oil
and gas industry for detecting and analyzing tension and possible
fractures in borehole walls. Most of these techniques are based on
manual observation of the captured borehole images. While this
strategy may be possible and convenient with small images and few
data, it may become difficult and suitable to errors when big
databases of images must be treated. While the patterns may differ
among the image area, depending on many characteristics (drilling
strategy, rock components, rock strength, etc.). In this work we
propose the inclusion of data-mining classification strategies in order
to create a knowledge database of the segmented curves. These
classifiers allow that, after some time using and manually pointing
parts of borehole images that correspond to tension regions and
breakout areas, the system will indicate and suggest automatically
new candidate regions, with higher accuracy. We suggest the use of
different classifiers methods, in order to achieve different knowledge
dataset configurations.
Abstract: This paper is concerning the issues of behaviour of
lightweight expanded clay aggregates concrete exposed to high
temperature. Lightweight aggregates from expanded clay are
produced by firing of row material up to temperature 1050°C.
Lightweight aggregates have suitable properties in terms of volume
stability, when exposed to temperatures up to 1050°C, which could
indicate their suitability for construction applications with higher risk
of fire. The test samples were exposed to heat by using the standard
temperature-time curve ISO 834. Negative changes in resulting
mechanical properties, such as compressive strength, tensile strength,
and flexural strength were evaluated. Also visual evaluation of the
specimen was performed. On specimen exposed to excessive heat, an
explosive spalling could be observed, due to evaporation of
considerable amount of unbounded water from the inner structure of
the concrete.
Abstract: This study aimed at investigating whether the
functional brain networks constructed using the initial EEG (obtained
when patients first visited hospital) can be correlated with the
progression of cognitive decline calculated as the changes of
mini-mental state examination (MMSE) scores between the latest and
initial examinations. We integrated the time–frequency cross mutual
information (TFCMI) method to estimate the EEG functional
connectivity between cortical regions, and the network analysis based
on graph theory to investigate the organization of functional networks
in aMCI. Our finding suggested that higher integrated functional
network with sufficient connection strengths, dense connection
between local regions, and high network efficiency in processing
information at the initial stage may result in a better prognosis of the
subsequent cognitive functions for aMCI. In conclusion, the functional
connectivity can be a useful biomarker to assist in prediction of
cognitive declines in aMCI.
Abstract: Brain functional networks based on resting-state EEG
data were compared between patients with mild Alzheimer’s disease
(mAD) and matched patients with amnestic subtype of mild cognitive
impairment (aMCI). We integrated the time–frequency cross mutual
information (TFCMI) method to estimate the EEG functional
connectivity between cortical regions and the network analysis based
on graph theory to further investigate the alterations of functional
networks in mAD compared with aMCI group. We aimed at
investigating the changes of network integrity, local clustering,
information processing efficiency, and fault tolerance in mAD brain
networks for different frequency bands based on several topological
properties, including degree, strength, clustering coefficient, shortest
path length, and efficiency. Results showed that the disruptions of
network integrity and reductions of network efficiency in mAD
characterized by lower degree, decreased clustering coefficient, higher
shortest path length, and reduced global and local efficiencies in the
delta, theta, beta2, and gamma bands were evident. The significant
changes in network organization can be used in assisting
discrimination of mAD from aMCI in clinical.
Abstract: The paper deals with current issues in research of
advanced methods to increase reliability of traditional timber
structural elements. It analyses the issue of strengthening of bent
timber beams, such as ceiling beams in old (historical) buildings with
additional concrete slab in combination with externally bonded fibre -
reinforced polymer. The paper describes experimental testing of
composite timber-concrete beam with FRP reinforcement and
compares results with FEM analysis.
Abstract: The effect of particle size on shear strength of
granular materials are investigated using direct shear tests. Small
direct shear test (60 mm by 60 mm by 24 mm deep) were conducted
for particles passing the sieves with opening size of 2.36 mm.
Meanwhile, particles passing the standard 20 mm sieves were tested
using large direct shear test (300 mm by 300 mm by 200 mm deep).
The large direct shear tests and the small direct shear tests carried out
using the same shearing rate of 0.09 mm/min and similar normal
stresses of 100, 200 and 300 kPa. The results show that the peak and
residual shear strength increases as particle size increases.
Abstract: This paper attempts to evaluate the effect of fire
damage on concrete by using nonlinear resonance vibration method,
one of the nonlinear nondestructive method. Concrete exhibits not
only nonlinear stress-strain relation but also hysteresis and discrete
memory effect which are contained in consolidated materials.
Hysteretic materials typically show the linear resonance frequency
shift. Also, the shift of resonance frequency is changed according to
the degree of micro damage. The degree of the shift can be obtained
through nonlinear resonance vibration method. Five exposure
scenarios were considered in order to make different internal micro
damage. Also, the effect of post-fire-curing on fire-damaged concrete
was taken into account to conform the change in internal damage.
Hysteretic nonlinearity parameter was obtained by amplitudedependent
resonance frequency shift after specific curing periods. In
addition, splitting tensile strength was measured on each sample to
characterize the variation of residual strength. Then, a correlation
between the hysteretic nonlinearity parameter and residual strength
was proposed from each test result.
Abstract: Well-designed composite steel and concrete structures
highlight the good material properties and lower the deficiencies of
steel and concrete, in particular they make use of high tensile strength
of steel and high stiffness of concrete. The most common composite
steel and concrete structure is a simply supported beam, which
concrete slab transferring the slab load to a beam is connected to the
steel cross-section. The aim of this paper is to find the most adequate
numerical model of a simply supported composite beam with the
cross-sectional and material parameters based on the results of a
processed parametric study and numerical analysis. The paper also
evaluates the suitability of using compact concrete with the
lightweight aggregates for composite steel and concrete beams. The
most adequate numerical model will be used in the resent future to
compare the results of laboratory tests.
Abstract: The fundamental issues in ICT Governance (ICTG)
implementation for Malaysian Public Sector (MPS) is how ICT be
applied to support improvements in productivity, management
effectiveness and the quality of services offered to its citizens. Our
main concern is to develop and adopt a common definition and
framework to illustrate how ICTG can be used to better align ICT
with government’s operations and strategic focus. In particular, we
want to identify and categorize factors that drive a successful ICTG
process. This paper presents the results of an exploratory study to
identify, validate and refine such Critical Success Factors (CSFs) and
confirmed seven CSFs and nineteen sub-factors as influential factors
that fit MPS after further validated and refined. The Delphi method
applied in validation and refining process before being endorsed as
appropriate for MPS. The identified CSFs reflect the focus areas that
need to be considered strategically to strengthen ICT Governance
implementation and ensure business success.
Abstract: Due to reduced stiffness, research on second
generation titanium alloys for implant applications, like the
metastable β-titanium alloy Ti-15Mo, become more and more
important in the recent years. The machinability of these alloys is
generally poor leading to problems during implant production and
comparably large production costs. Therefore, in the present study,
Ti-15Mo was alloyed with 0.8 wt.-% of the rare earth metals
lanthanum (Ti-15Mo+0.8La) and neodymium (Ti-15Mo+0.8Nd) to
improve its machinability. Their microstructure consisted of a
titanium matrix and micrometer-size particles of the rare earth metals
and two of their oxides. The particles stabilized the microstructure as
grain growth was minimized. As especially the ductility might be
affected by the precipitates, the behavior of Ti-15Mo+0.8La and Ti-
15Mo+0.8Nd was investigated during static and dynamic
deformation at elevated temperature to develop a processing route.
The resulting mechanical properties (static strength and ductility)
were similar in all investigated alloys.
Abstract: Copper being one of the major intrinsic residual
impurities in steel possesses the tendency to induce severe
microstructural distortions if not controlled within certain limits.
Hence, this paper investigates the effect of this element on the
mechanical properties of construction steel with a view to ascertain
its safe limits for effective control. The experiment entails collection
of statistically scheduled samples of hot rolled profiles with varied
copper concentrations in the range of 0.12-0.39 wt. %. From these
samples were prepared standard test specimens subjected to tensile,
impact, hardness and microstructural analyses. Results show a rather
huge compromise in mechanical properties as the specimens
demonstrated 54.3%, 74.2% and 64.9% reduction in tensile strength,
impact energy and hardness respectively as copper content increases
from 0.12 wt. % to 0.39 wt. %. The steel’s abysmal performance is
due to the severe distortion of the microstructure occasioned by the
development of incoherent complex compounds which weaken the
pearlite reinforcing phase. It is concluded that the presence of copper
above 0.22 wt. % is deleterious to construction steel performance.
Abstract: This entry concerned with dense silica bricks
microstructure was produced as a part of a project within the
Technology Agency of the Czech Republic which is being
implemented in cooperation of the biggest producer of refractories
the P-D Refractories CZ company with the research organisation
Brno University of Technology. The paper is focused on the
influence of mixture homogenisation and the influence of grain size
of the mineraliser on the resulting utility properties of the material as
well as its microstructure. It has a decisive influence on the durability
of the material in a building structure. This paper is a continuation of
a previously published study dealing with the suitability of various
types of mineralising agents in terms of density, strength and mineral
composition of silica brick.
The entry describes the influence of the method of mixture
homogenisation and the influence of granulometry of the applied Femineralising
agent on the resulting silica microstructure. Porosity,
density, phase composition and microstructure of the experimentally
prepared silica bricks samples were examined and the results were
discussed in context with the technology of homogenisation and
firing temperature used. The properties of silica bricks samples were
compared to the sample without any Fe-mineraliser.
Abstract: The aim of this paper is to analyze the ability to
identify and acquire knowledge from external sources at the regional
level in the Czech Republic. The results show that the most important
sources of knowledge for innovative activities are sources within the
businesses themselves, followed by customers and suppliers.
Furthermore, the analysis of relationships between the objective of
the innovative activity and the ability to identify and acquire
knowledge implies that knowledge obtained from (1) customers aims
at replacing outdated products and increasing product quality; (2)
suppliers aims at increasing capacity and flexibility of production;
and (3) competing businesses aims at growing market share and
increasing the flexibility of production and services. Regions should
therefore direct their support especially into development and
strengthening of networks within the value chain.
Abstract: Chloride resistance in Ultra High Performance
Concrete (UHPC) is determined in this paper. This work deals with
the one dimension chloride transport, which can be potentially
dangerous particularly for the durability of concrete structures. Risk
of reinforcement corrosion due to exposure to the concrete surface to
direct the action of chloride ions (mainly in the form de-icing salts or
groundwater) is dangerously increases. The measured data are
investigated depending on the depth of penetration of chloride ions
into the concrete structure. Comparative measurements with normal
strength concrete are done as well. The experimental results showed
that UHCP have improved resistance of chlorides penetration than
NSC and also chloride diffusion depth is significantly lower in
UHCP.
Abstract: The paper a summary of the results of concretes with
partial substitution of natural aggregates with recycled concrete is
solved. Design formulas of the concretes were characterised with 20,
40 and 60% substitution of natural 8-16mm fraction aggregates with
a selected recycled concrete of analogous coarse fractions. With the
product samples an evaluation of coarse fraction aggregates influence
on fresh concrete consistency and concrete strength in time was
carried out. The results of concretes with aggregates substitution will
be compared to reference formula containing only the fractions of
natural aggregates.
Abstract: The article presents the trends in Georgian wine
market development and evaluates the competitive advantages of
Georgia to enter the wine market based on its customs, traditions and
historical practices combined with modern technologies.
In order to analyze the supply of wine, dynamics of vineyard land
area and grape varieties are discussed, trends in wine production are
presented, trends in export and import are evaluated, local wine
market, its micro and macro environments are studied and analyzed
based on the interviews with experts and analysis of initial recording
materials.
For strengthening its position on the international market, the level
of competitiveness of Georgian wine is defined, which is evaluated
by “ex-ante” and “ex-post” methods, as well as by four basic and two
additional factors of the Porter’s diamond method; potential
advantages and disadvantages of Georgian wine are revealed.
Conclusions are made by identifying the factors that hinder the
development of Georgian wine market. Based on the conclusions,
relevant recommendations are developed.