Abstract: The relationship between eigenstructure (eigenvalues
and eigenvectors) and latent structure (latent roots and latent vectors)
is established. In control theory eigenstructure is associated with
the state space description of a dynamic multi-variable system and
a latent structure is associated with its matrix fraction description.
Beginning with block controller and block observer state space forms
and moving on to any general state space form, we develop the
identities that relate eigenvectors and latent vectors in either direction.
Numerical examples illustrate this result. A brief discussion of the
potential of these identities in linear control system design follows.
Additionally, we present a consequent result: a quick and easy
method to solve the polynomial eigenvalue problem for regular matrix
polynomials.
Abstract: Two types of commercial cylindrical lithium ion
batteries (Panasonic 3.4 Ah NCR-18650B and Samsung 2.9 Ah
INR-18650), were investigated experimentally. The capacities of these
samples were individually measured using constant current-constant
voltage (CC-CV) method at different ambient temperatures (-10°C,
0°C, 25°C). Their internal resistance was determined by
electrochemical impedance spectroscopy (EIS) and pulse discharge
methods. The cells with different configurations of parallel connection
NCR-NCR, INR-INR and NCR-INR were charged/discharged at the
aforementioned ambient temperatures. The results showed that the
difference of internal resistance between cells much more evident at
low temperatures. Furthermore, the parallel connection of NCR-NCR
exhibits the most uniform temperature distribution in cells at -10°C,
this feature is quite favorable for the safety of the battery pack.
Abstract: During welding, the amount of heat present in weld
zones determines the quality of weldment produced. Thus, the heat
distribution characteristics and its magnitude in weld zones with
respect to process variables such as tool pin-shoulder rotational and
traveling speed during welding is analyzed using thermal finite
element analyses method. For this purpose, transient thermal finite
element analyses are performed to model the temperatures
distribution and its quantities in weld-zones with respect to process
variables such as rotational speed and traveling speed during welding.
Commercially available software Altair HyperWork is used to model
three-dimensional tool pin-shoulder vs. workpieces and to simulate
the friction stir process. The results show that increasing tool
rotational speed, at a constant traveling speed, will increase the
amount of heat generated in weld-zones. In contrary, increasing
traveling speed, at constant tool pin-shoulder rotational speeds, will
reduce the amount of heat generated in weld zones.
Abstract: Frequent, continuous speech training has proven to be
a necessary part of a successful speech therapy process, but
constraints of traveling time and employment dispensation become
key obstacles especially for individuals living in remote areas or for
dependent children who have working parents. In order to ameliorate
speech difficulties with ample guidance from speech therapists, a
website has been developed that supports speech therapy and training
for people with articulation disorders in the standard Thai language.
This web-based program has the ability to record speech training
exercises for each speech trainee. The records will be stored in a
database for the speech therapist to investigate, evaluate, compare
and keep track of all trainees’ progress in detail. Speech trainees can
request live discussions via video conference call when needed.
Communication through this web-based program facilitates and
reduces training time in comparison to walk-in training or
appointments. This type of training also allows people with
articulation disorders to practice speech lessons whenever or
wherever is convenient for them, which can lead to a more regular
training processes.
Abstract: In this paper, strontium ferrite (SrO.6Fe2O3) was
synthesized by the sol-gel auto-combustion process. The thermal
behavior of powder obtained from self-propagating combustion of
initial gel was evaluated by simultaneous differential thermal analysis
(DTA) and thermo gravimetric (TG), from room temperature to
1200°C. The as-burnt powder was calcined at various temperatures
from 700-900°C to achieve the single-phase Sr-ferrite. Phase
composition, morphology and magnetic properties were investigated
using X-ray diffraction (XRD), transmission electron microscopy
(TEM) and vibrating sample magnetometry (VSM) techniques.
Results showed that the single-phase and nano-sized hexagonal
strontium ferrite particles were formed at calcination temperature of
800°C with crystallite size of 27 nm and coercivity of 6238 Oe.
Abstract: One of the most important tasks in urban remote
sensing is the detection of impervious surfaces (IS), such as roofs and
roads. However, detection of IS in heterogeneous areas still remains
one of the most challenging tasks. In this study, detection of concrete
roof using an object-based approach was proposed. A new rule-based
classification was developed to detect concrete roof tile. This
proposed rule-based classification was applied to WorldView-2
image and results showed that the proposed rule has good potential to
predict concrete roof material from WorldView-2 images, with 85%
accuracy.
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.
Abstract: The paper discusses economic policy of Georgia
aiming to increase national competitiveness as well as the tools and
means which will help to improve the competitiveness of the country.
The sectors of the economy, in which the country can achieve the
competitive advantage, are studied. It is noted that the country’s
economic policy plays an important role in obtaining and maintaining
the competitive advantage - authority should take measures to ensure
high level of education; scientific and research activities should be
funded by the state; foreign direct investments should be attracted
mainly in science-intensive industries; adaptation with the latest
scientific achievements of the modern world and deepening of
scientific and technical cooperation. Stable business environment and
export oriented strategy is the basis for the country’s economic
growth.
As the outcome of the research, the paper suggests the strategy for
improving competitiveness in Georgia; recommendations are
provided based on relevant conclusions.
Abstract: The importance of the formal specification in the
software life cycle is barely concealing to anyone. Formal
specifications use mathematical notation to describe the properties of
information system precisely, without unduly constraining the way in
how these properties are achieved. Having a correct and quality
software specification is not easy task. This study concerns with how
a group of rectifiers can communicate with each other and work to
prepare and produce a correct formal software specification. WBCS
has been implemented based mainly in the proposed supported
cooperative work model and a survey conducted on the existing Webbased
collaborative writing tools. This paper aims to assess the
feasibility of executing the web-based collaboration process using
WBCS. The purpose of conducting this test is to test the system as a
whole for functionality and fitness for use based on the evaluation
test plan.
Abstract: Among all FACTS devices, the unified power flow
controller (UPFC) is considered to be the most versatile device.
This is due to its capability to control all the transmission system
parameters (impedance, voltage magnitude, and phase angle). With
the growing interest in UPFC, the attention to develop a mathematical
model has increased. Several models were introduced for UPFC in
literature for different type of studies in power systems. In this paper
a novel comparison study between two dynamic models of UPFC
with their proposed control strategies.
Abstract: Researches and concerns in power quality gained
significant momentum in the field of power electronics systems over
the last two decades globally. This sudden increase in the number of
concerns over power quality problems is a result of the huge increase
in the use of non-linear loads. In this paper, power quality evaluation
of some distribution networks at Misurata - Libya has been done
using a power quality and energy analyzer (Fluke 437 Series II). The
results of this evaluation are used to minimize the problems of power
quality. The analysis shows the main power quality problems that
exist and the level of awareness of power quality issues with the aim
of generating a start point which can be used as guidelines for
researchers and end users in the field of power systems.
Abstract: This work proposes a fuzzy methodology to support
the investment decisions. While choosing among competitive
investment projects, the methodology makes ranking of projects
using the new aggregation OWA operator – AsPOWA, presented in
the environment of possibility uncertainty. For numerical evaluation
of the weighting vector associated with the AsPOWA operator the
mathematical programming problem is constructed. On the basis of
the AsPOWA operator the projects’ group ranking maximum criteria
is constructed. The methodology also allows making the most
profitable investments into several of the project using the method
developed by the authors for discrete possibilistic bicriteria problems.
The article provides an example of the investment decision-making
that explains the work of the proposed methodology.
Abstract: Recent perceived climate variability raises concerns
with unprecedented hydrological phenomena and extremes.
Distribution and circulation of the waters of the Earth become
increasingly difficult to determine because of additional uncertainty
related to anthropogenic emissions. The world wide observed
changes in the large-scale hydrological cycle have been related to an
increase in the observed temperature over several decades. Although
the effect of change in climate on hydrology provides a general
picture of possible hydrological global change, new tools and
frameworks for modelling hydrological series with nonstationary
characteristics at finer scales, are required for assessing climate
change impacts. Of the downscaling techniques, dynamic
downscaling is usually based on the use of Regional Climate Models
(RCMs), which generate finer resolution output based on atmospheric
physics over a region using General Circulation Model (GCM) fields
as boundary conditions. However, RCMs are not expected to capture
the observed spatial precipitation extremes at a fine cell scale or at a
basin scale. Statistical downscaling derives a statistical or empirical
relationship between the variables simulated by the GCMs, called
predictors, and station-scale hydrologic variables, called predictands.
The main focus of the paper is on the need for using statistical
downscaling techniques for projection of local hydrometeorological
variables under climate change scenarios. The projections can be then
served as a means of input source to various hydrologic models to
obtain streamflow, evapotranspiration, soil moisture and other
hydrological variables of interest.
Abstract: As an entity of the tourism system, local communities
were considered have better understanding of their region as well as
influenced positively or negatively by the tourism activities in the
region. This paper aimed to study role of community involvement in
the development of ecotourism at Kintamani Bali from two
perspectives of view, i.e. participation in the process of initiatives and
participation in the utilizing the economic benefits of tourism.
Thorough participation as an antecedent of social capital form, the
sustainability of ecotourism at Kintamani could be expected.
Abstract: Natural antimicrobials are used to preserve foods that
can be found in plants, animals, and microorganisms. Antimicrobial
substances are natural or artificial agents that produced by
microorganisms or obtained semi/total chemical synthesis are used at
low concentrations to inhibit the growth of other microorganisms.
Food borne pathogens and spoilage microorganisms are inactivated
by the use of antagonistic microorganisms and their metabolites.
Yeasts can produce toxic proteins or glycoproteins (toxins) that cause
inhibition of sensitive bacteria and yeast species. Antimicrobial
substance producing phenotypes belonging different yeast genus
were isolated from different sources. Toxins secreted by many yeast
strains inhibiting the growth of other yeast strains. These strains show
antimicrobial activity, inhibiting the growth of mold and bacteria.
The effect of antimicrobial agents produced by yeasts can be
extremely fast, and therefore may be used in various treatment
procedures. Rapid inhibition of microorganisms is possibly caused by
microbial cell membrane lipopolysaccharide binding and in
activation (neutralization) effect. Antimicrobial agents inhibit the
target cells via different mechanisms of action.
Abstract: The work proposes a decision support methodology
for the credit risk minimization in selection of investment projects.
The methodology provides two stages of projects’ evaluation.
Preliminary selection of projects with minor credit risks is made
using the Expertons Method. The second stage makes ranking of
chosen projects using the Possibilistic Discrimination Analysis
Method. The latter is a new modification of a well-known Method of
Fuzzy Discrimination Analysis.
Abstract: A generalized vortex lattice method for complex
lifting surfaces with flap and aileron deflection is formulated. The
method is not restricted by the linearized theory assumption and
accounts for all standard geometric lifting surface parameters:
camber, taper, sweep, washout, dihedral, in addition to flap and
aileron deflection. Thickness is not accounted for since the physical
lifting body is replaced by a lattice of panels located on the mean
camber surface. This panel lattice setup and the treatment of different
wake geometries is what distinguish the present work form the
overwhelming majority of previous solutions based on the vortex
lattice method. A MATLAB code implementing the proposed
formulation is developed and validated by comparing our results to
existing experimental and numerical ones and good agreement is
demonstrated. It is then used to study the accuracy of the widely used
classical vortex-lattice method. It is shown that the classical approach
gives good agreement in the clean configuration but is off by as much
as 30% when a flap or aileron deflection of 30° is imposed. This
discrepancy is mainly due the linearized theory assumption
associated with the conventional method. A comparison of the effect
of four different wake geometries on the values of aerodynamic
coefficients was also carried out and it is found that the choice of the
wake shape had very little effect on the results.
Abstract: This paper clarifies the role of ICT capital in economic
growth. Albeit ICT remarkably contributes to economic growth, there
are few studies on ICT capital in ICT sector from theoretical point of
view. In this paper, production function of ICT which is used as input
of intermediate good in final good and ICT sectors is incorporated
into our model. In this setting, we analyze the role of ICT on balance
growth path and show the possibility of general equilibrium solutions
for this model. Through the simulation of the equilibrium solutions,
we find that when ICT impacts on economy and economic growth
increases, it is necessary that increases of efficiency at ICT sector and
of accumulation of non-ICT and ICT capitals occur simultaneously.
Abstract: Sudoku is a logic-based combinatorial puzzle game
which people in different ages enjoy playing it. The challenging and
addictive nature of this game has made it a ubiquitous game. Most
magazines, newspapers, puzzle books, etc. publish lots of Sudoku
puzzles every day. These puzzles often come in different levels of
difficulty so that all people, from beginner to expert, can play the
game and enjoy it. Generating puzzles with different levels of
difficulty is a major concern of Sudoku designers. There are several
works in the literature which propose ways of generating puzzles
having a desirable level of difficulty. In this paper, we propose a
method based on constraint satisfaction problems to evaluate the
difficulty of the Sudoku puzzles. Then we propose a hill climbing
method to generate puzzles with different levels of difficulty.
Whereas other methods are usually capable of generating puzzles
with only few number of difficulty levels, our method can be used to
generate puzzles with arbitrary number of different difficulty levels.
We test our method by generating puzzles with different levels of
difficulty and having a group of 15 people solve all the puzzles and
recording the time they spend for each puzzle.
Abstract: The effect of various humidities on process yields and
degrees of crystallinity for spray-dried powders from spray drying of
lactose with humid air in a straight-through system have been
studied. It has been suggested by Williams–Landel–Ferry kinetics
(WLF) that a higher particle temperature and lower glass-transition
temperature would increase the crystallization rate of the particles
during the spray-drying process. Freshly humidified air produced by
a Buchi-B290 spray dryer as a humidifier attached to the main spray
dryer decreased the particle glass-transition temperature (Tg), while
allowing the particle temperature (Tp) to reach higher values by using
an insulated drying chamber. Differential scanning calorimetry
(DSC) and moisture sorption analysis were used to measure the
degree of crystallinity for the spray-dried lactose powders. The
results showed that higher Tp-Tg, as a result of applying humid air,
improved the process yield from 21 ± 4 to 26 ± 2% and crystallinity
of the particles by decreasing the latent heat of crystallization from
43 ± 1 to 30 ± 11 J/g and the sorption peak height from 7.3 ± 0.7% to
6 ± 0.7%.