Abstract: Small signal stability causes small perturbations in the
generator that can cause instability in the power network. It is
generally known that small signal stability are directly related to the
generator and load properties. This paper examines the effects of
generator input variations on power system oscillations for a small
signal stability study. Eigenvaules and eigenvectors are used to
examine the stability of the power system. The dynamic power
system's mathematical model is constructed and thus calculated using
load flow and small signal stability toolbox on MATLAB. The power
system model is based on a 3-machine 9-bus system that was
modified to suit this study. In this paper, Participation Factors are a
means to gauge the effects of variation in generation with other
parameters on the network are also incorporated.
Abstract: Ground-level tropospheric ozone is one of the air
pollutants of most concern. It is mainly produced by photochemical
processes involving nitrogen oxides and volatile organic compounds
in the lower parts of the atmosphere. Ozone levels become
particularly high in regions close to high ozone precursor emissions
and during summer, when stagnant meteorological conditions with
high insolation and high temperatures are common.
In this work, some results of a study about urban ozone
distribution patterns in the city of Badajoz, which is the largest and
most industrialized city in Extremadura region (southwest Spain) are
shown. Fourteen sampling campaigns, at least one per month, were
carried out to measure ambient air ozone concentrations, during
periods that were selected according to favourable conditions to
ozone production, using an automatic portable analyzer.
Later, to evaluate the ozone distribution at the city, the measured
ozone data were analyzed using geostatistical techniques. Thus, first,
during the exploratory analysis of data, it was revealed that they were
distributed normally, which is a desirable property for the subsequent
stages of the geostatistical study. Secondly, during the structural
analysis of data, theoretical spherical models provided the best fit for
all monthly experimental variograms. The parameters of these
variograms (sill, range and nugget) revealed that the maximum
distance of spatial dependence is between 302-790 m and the
variable, air ozone concentration, is not evenly distributed in reduced
distances. Finally, predictive ozone maps were derived for all points
of the experimental study area, by use of geostatistical algorithms
(kriging). High prediction accuracy was obtained in all cases as
cross-validation showed. Useful information for hazard assessment
was also provided when probability maps, based on kriging
interpolation and kriging standard deviation, were produced.
Abstract: The question of interethnic and interreligious conflicts
in ex-Yugoslavia receives much attention within the framework of
the international context created after 1991 because of the impact of
these conflicts on the security and the stability of the region of
Balkans and of Europe.
This paper focuses on the rationales leading to the declaration of
independence by Kosovo according to ethnic and religious criteria
and analyzes why these same rationales were not applied in Bosnia
and Herzegovina. The approach undertaken aims at comparatively
examining the cases of Kosovo, and Bosnia and Herzegovina. At the
same time, it aims at understanding the political decision making of
the international community in the case of Kosovo. Specifically, was
this a good political decision for the security and the stability of the
region of Balkans, of Europe, or even for global security and
stability?
This research starts with an overview on the European security
framework post 1991, paying particular attention to Kosovo and
Bosnia and Herzegovina. It then presents the theoretical and
methodological framework and compares the representative cases.
Using the constructivism issue and the comparative methodology, it
arrives at the results of the study. An important issue of the paper is
the thesis that this event modifies the principles of international law
and creates dangerous precedents for regional stability in the
Balkans.
Abstract: Through 1980s, management accounting researchers
described the increasing irrelevance of traditional control and
performance measurement systems. The Balanced Scorecard (BSC)
is a critical business tool for a lot of organizations. It is a
performance measurement system which translates mission and
strategy into objectives. Strategy map approach is a development
variant of BSC in which some necessary causal relations must be
established. To recognize these relations, experts usually use
experience. It is also possible to utilize regression for the same
purpose. Structural Equation Modeling (SEM), which is one of the
most powerful methods of multivariate data analysis, obtains more
appropriate results than traditional methods such as regression. In the
present paper, we propose SEM for the first time to identify the
relations between objectives in the strategy map, and a test to
measure the importance of relations. In SEM, factor analysis and test
of hypotheses are done in the same analysis. SEM is known to be
better than other techniques at supporting analysis and reporting. Our
approach provides a framework which permits the experts to design
the strategy map by applying a comprehensive and scientific method
together with their experience. Therefore this scheme is a more
reliable method in comparison with the previously established
methods.
Abstract: The mobile users with Laptops need to have an
efficient access to i.e. their home personal data or to the Internet from
any place in the world, regardless of their location or point of
attachment, especially while roaming outside the home subnet. An
efficient interpretation of packet losses problem that is encountered
from this roaming is to the centric of all aspects in this work, to be
over-highlighted. The main previous works, such as BER-systems,
Amigos, and ns-2 implementation that are considered to be in
conjunction with that problem under study are reviewed and
discussed. Their drawbacks and limitations, of stopping only at
monitoring, and not to provide an actual solution for eliminating or
even restricting these losses, are mentioned. Besides that, the
framework around which we built a Triple-R sequence as a costeffective
solution to eliminate the packet losses and bridge the gap
between subnets, an area that until now has been largely neglected, is
presented. The results show that, in addition to the high bit error rate
of wireless mobile networks, mainly the low efficiency of mobile-IP
registration procedure is a direct cause of these packet losses.
Furthermore, the output of packet losses interpretation resulted an
illustrated triangle of the registration process. This triangle should be
further researched and analyzed in our future work.
Abstract: Cutting tools are widely used in manufacturing processes and drilling is the most commonly used machining process. Although drill-bits used in drilling may not be expensive, their breakage can cause damage to expensive work piece being drilled and at the same time has major impact on productivity. Predicting drill-bit breakage, therefore, is important in reducing cost and improving productivity. This study uses twenty features extracted from two degradation signals viz., thrust force and torque. The methodology used involves developing and comparing decision tree, random forest, and multinomial logistic regression models for classifying and predicting drill-bit breakage using degradation signals.
Abstract: Selecting the data modeling technique for an
information system is determined by the objective of the resultant
data model. Dimensional modeling is the preferred modeling
technique for data destined for data warehouses and data mining,
presenting data models that ease analysis and queries which are in
contrast with entity relationship modeling. The establishment of data
warehouses as components of information system landscapes in
many organizations has subsequently led to the development of
dimensional modeling. This has been significantly more developed
and reported for the commercial database management systems as
compared to the open sources thereby making it less affordable for
those in resource constrained settings. This paper presents
dimensional modeling of HIV patient information using open source
modeling tools. It aims to take advantage of the fact that the most
affected regions by the HIV virus are also heavily resource
constrained (sub-Saharan Africa) whereas having large quantities of
HIV data. Two HIV data source systems were studied to identify
appropriate dimensions and facts these were then modeled using two
open source dimensional modeling tools. Use of open source would
reduce the software costs for dimensional modeling and in turn make
data warehousing and data mining more feasible even for those in
resource constrained settings but with data available.
Abstract: This paper presents an alternative strategy of queuing
handover called Pseudo Last Useful Instant PLUI scheme for Low
Earth Orbit Mobile Satellite Systems LEO MSSs. The PLUI scheme
uses the same approach as the Last Useful Instant LUI scheme
previously proposed in literature, with less complex implementation.
Simulation tests were carried out using Dynamic Channel Allocation
DCA in order to evaluate the performance of this scheme and also an
analytical approach has been presented to allow the performance
evaluation of Fixed Channel Allocation FCA, with different
handover queuing disciplines. The results show that performances
achieved by the proposed strategy are close to those achieved using
the LUI scheme.
Abstract: The mobile systems are powered by batteries.
Reducing the system power consumption is a key to increase its
autonomy. It is known that mostly the systems are dealing with time
varying signals. Thus, we aim to achieve power efficiency by smartly
adapting the system processing activity in accordance with the input
signal local characteristics. It is done by completely rethinking the
processing chain, by adopting signal driven sampling and processing.
In this context, a signal driven filtering technique, based on the level
crossing sampling is devised. It adapts the sampling frequency and
the filter order by analysing the input signal local variations. Thus, it
correlates the processing activity with the signal variations. It leads
towards a drastic computational gain of the proposed technique
compared to the classical one.
Abstract: A new method identifies coupled fluid-structure system with a reduced set of state variables is presented. Assuming that the structural model is known a priori either from an analysis or a test and using linear transformations between structural and aeroelastic states, it is possible to deduce aerodynamic information from sampled time histories of the aeroelastic system. More specifically given a finite set of structural modes the method extracts generalized aerodynamic force matrix corresponding to these mode shapes. Once the aerodynamic forces are known, an aeroelastic reduced-order model can be constructed in discrete-time, state-space format by coupling the structural model and the aerodynamic system. The resulting reduced-order model is suitable for constant Mach, varying density analysis.
Abstract: This study aims to conduct a preliminary investigation to determine the topic to be focused in developing Virtual Laboratory For Biology (VLab-Bio). Samples involved in answering the questionnaire are form five students (equivalent to A-Level) and biology teachers. Time and economical resources for the setting up and construction of scientific laboratories can be solved with the adaptation of virtual laboratories as an educational tool. Thus, it is hoped that the proposed virtual laboratory will help students to learn the abstract concepts in biology. Findings show that the difficult topic chosen is Cell Division and the learning objective to be focused in developing the virtual lab is “Describe the application of knowledge on mitosis in cloning".
Abstract: Eight heavy metals (Cu, Cr, Zn, Hg, Pb, Cd, Ni and As) were analyzed in sediment samples in the dry and wet seasons from November 2009 to October 2010 in West Port of Peninsular Malaysia. The heavy metal concentrations (mg/kg dry weight) were ranged from 23.4 to 98.3 for Zn, 22.3 to 80 for Pb, 7.4 to 27.6 Cu, 0.244 to 3.53 for Cd, 7.2 to 22.2 for Ni, 20.2 to 162 for As, 0.11 to 0.409 for Hg and 11.5 to 61.5 for Cr. Metals concentrations in dry season were higher than the rainy season except in cupper and chromium. Analysis of variance with Statistical Analysis System (SAS) shows that the mean concentration of metals in the two seasons (α level=0.05) are not significantly different which shows that the metals were held firmly in the matrix of sediment. Also there are significant differences between control point station with other stations. According to the Interim Sediment Quality guidelines (ISQG), the metal concentrations are moderately polluted, except in arsenic which shows the highest level of pollution.
Abstract: Legionella pneumophila is involved in more than 95%
cases of severe atypical pneumonia. Infection is mainly by
inhalation the indoor aerosols through the water-coolant systems.
Because some Legionella strains may be viable but not culturable,
therefore, Taq polymerase, DNA amplification and semi-nested-PCR
were carried out to detect Legionella-specific 16S-rDNA sequence.
For this purpose, 1.5 litter of water samples from 77 water-coolant
system were collected from four different hospitals, two nursing
homes and one student hostel in Kerman city of Iran, each in a brand
new plastic bottle during summer season of 2006 (from April to
August). The samples were filtered in the sterile condition through
the Millipore Membrane Filter. DNA was extracted from membrane
and used for PCR to detect Legionella spp. The PCR product was
then subjected to semi-nested PCR for detection of L. pneumophila.
Out of 77 water samples that were tested by PCR, 30 (39%) were
positive for most species of Legionella. However, L. pneumophila
was detected from 14 (18.2%) water samples by semi-nested PCR.
From the above results it can be concluded that water coolant
systems of different hospitals and nursing homes in Kerman city of
Iran are highly contaminated with L. pneumophila spp. and pose
serious concern. So, we recommend avoiding such type of coolant
system in the hospitals and nursing homes.
Abstract: Cantilever L-shaped walls are known to be relatively economical as retaining solution. The design starts by proportioning the wall dimensions for which the stability is checked for. A ratio between the lengths of the base and the stem, falling between 0.5 to 0.7 ensure in most case the stability requirements, however, the displacement pattern of the wall in terms of rotations and translations, and the lateral pressure profile, do not have the same figure for all wall’s proportioning, as it is usually assumed. In the present work the results of a numerical analysis are presented, different wall geometries were considered. The results show that the proportioning governs the equilibrium between the instantaneous rotation and the translation of the wall-toe, also, the lateral pressure estimation based on the average value between the at-rest and the active pressure, recommended by most design standards, is found to be not applicable for all walls.
Abstract: This article presents a performance comparison of an
interior mounted permanent magnet synchronous generator (IPMSG)
with a synchronous reluctance generator (SynRG) with the same size
for a wind application. It is found that using the same geometrical
dimensions, a SynRG can convert 74 % of the power that an IPMSG
can convert, while it has 80% of the IPMSG weight. Moreover it is
found that the efficieny for the IMPSG is 99% at rated power
compared to 98.7% for the SynRG.
Abstract: Data Warehouses (DWs) are repositories which contain the unified history of an enterprise for decision support. The data must be Extracted from information sources, Transformed and integrated to be Loaded (ETL) into the DW, using ETL tools. These tools focus on data movement, where the models are only used as a means to this aim. Under a conceptual viewpoint, the authors want to innovate the ETL process in two ways: 1) to make clear compatibility between models in a declarative fashion, using correspondence assertions and 2) to identify the instances of different sources that represent the same entity in the real-world. This paper presents the overview of the proposed framework to model the ETL process, which is based on the use of a reference model and perspective schemata. This approach provides the designer with a better understanding of the semantic associated with the ETL process.
Abstract: This paper aims to present knowledge management for solving economic problem and poverty in Thai community. A community in Thailand is studied as a case study for master plan or social and economic plan which derived form the research people conducted by themselves in their community. The result shows that community uses knowledge management in recording income and expense, analyzing their consumption, and then systematic planning of the production, distribution and consumption in the community. Besides, community enterprises, that people create as the by-products of master plan, can facilitate diverse economic activities which are able to reduce economic problem and poverty. The knowledge that people gain from solving their problem through building community enterprises are both tacit and explicit knowledge. Four styles of knowledge conversion: socialization,externalization, combination and internalization, are used. Besides, knowledge sharing inside the organization, between organizations and its environment are found. Keywordsknowledge management, community enterprise, Thailand.
Abstract: In this paper, we proposed a new framework to incorporate an intelligent agent software robot into a crisis communication portal (CCNet) in order to send alert news to subscribed users via email and other mobile services such as Short Message Service (SMS), Multimedia Messaging Service (MMS) and General Packet Radio Services (GPRS). The content on the mobile services can be delivered either through mobile phone or Personal Digital Assistance (PDA). This research has shown that with our proposed framework, the embodied conversation agents system can handle questions intelligently with our multilayer architecture. At the same time, the extended framework can take care of delivery content through a more humanoid interface on mobile devices.
Abstract: The aim of this study was to extract sugar from
sugarcane using high electric field pulse (HELP) as a non-thermal cell permeabilization method. The result of this study showed that it
is possible to permeablize sugar cane cells using HELP at very short times (less than 10 sec.) and at room temperature. Increasing the field strength (from 0.5kV/cm to 2kV/cm) and pulse number (1 to 12) led to increasing the permeabilization of sugar cane cells. The energy
consumption during HELP treatment of sugar cane (2.4 kJ/kg) was about 100 times less compared to thermal cell disintegration at 85
Abstract: A game animals – elk (Alces alces), deer (Cervus
elaphus), roe deer (Capreolus capreolus) or wild boar (Sus scrofa
scrofa) - every autumn and winter period provide an excellent
investment, diversification of many consumer meals. In last years
consumption and assortiment of game meat products significantly
increase. Investigations about biochemical composition of game meat
are not very much. The meat of wild animals is more favourable for
human health because it has lower saturated fatty acids content, but
higher content of protein. Therefore the aim of investigations was to
compare biochemical composition of ungulates obtained in
Latvia.Investigations were carried out in wild animals different
regions of Latvia. In the studied samples protein, intramuscular fat,
fatty acids and cholesterol were determined. The biochemical
analysis of 54 samples were done. Results of analysis showed that
protein content 22.36 – 22.92% of all types of meat samples is not
different statistically, significantly lower fat content 1.33 ± 0.88%
had elk meat samples and 1.59 ± 0.59% roe deer samples. Content of
cholesterol was various 64.41 – 95.07% in the ruminant meat
samples of different species. From the dietetic point of view the best
composition of fatty acids has meat samples of roe deer.