Abstract: Voltage flicker is a disturbance in electrical power
systems. The reason for this disturbance is mainly the large nonlinear
loads such as electric arc furnaces. Synchronous static
compensator (STATCOM) is considered as a proper technique to
mitigate the voltage flicker. Application of more suitable and precise
power electronic converter leads to a more precise performance of the
compensator. In this paper a three-level 12-pulse voltage source
inverter (VSI) with a 12-terminal transformer connected to the ac
system is studied and the obtained results are compared with the
performance of a STATCOM using a simple two-level VSI and an
optimal and more precise performance of the proposed scheme is
achieved.
Abstract: Standards for learning objects focus primarily on
content presentation. They were already extended to support automatic evaluation but it is limited to exercises with a predefined
set of answers. The existing standards lack the metadata required by specialized evaluators to handle types of exercises with an indefinite
set of solutions. To address this issue existing learning object standards were extended to the particular requirements of a
specialized domain. A definition of programming problems as learning objects, compatible both with Learning Management Systems and with systems performing automatic evaluation of
programs, is presented in this paper. The proposed definition includes
metadata that cannot be conveniently represented using existing standards, such as: the type of automatic evaluation; the requirements
of the evaluation engine; and the roles of different assets - tests cases, program solutions, etc. The EduJudge project and its main services
are also presented as a case study on the use of the proposed definition of programming problems as learning objects.
Abstract: This paper proposes an efficient lattice-reduction-aided
detection (LRD) scheme to improve the detection performance of
MIMO-OFDM system. In this proposed scheme, V candidate symbols
are considered at the first layer, and V probable streams are
detected with LRD scheme according to the first detected V candidate
symbols. Then, the most probable stream is selected through a ML
test. Since the proposed scheme can more accurately detect initial
symbol and can reduce transmission of error to rest symbols, the
proposed scheme shows more improved performance than conventional
LRD with very low complexity.
Abstract: In this paper we propose a framework for
multisensor intrusion detection called Fuzzy Agent-Based Intrusion
Detection System. A unique feature of this model is that the agent
uses data from multiple sensors and the fuzzy logic to process log
files. Use of this feature reduces the overhead in a distributed
intrusion detection system. We have developed an agent
communication architecture that provides a prototype
implementation. This paper discusses also the issues of combining
intelligent agent technology with the intrusion detection domain.
Abstract: High voltage generators are being subject to higher
voltage rating and are being designed to operate in harsh conditions.
Stator windings are the main component of generators in which
Electrical, magnetically and thermal stresses remain major failures
for insulation degradation accelerated aging. A large number of
generators failed due to stator winding problems, mainly insulation
deterioration. Insulation degradation assessment plays vital role in the
asset life management. Mostly the stator failure is catastrophic
causing significant damage to the plant. Other than generation loss,
stator failure involves heavy repair or replacement cost. Electro
thermal analysis is the main characteristic for improvement design of
stator slot-s insulation. Dielectric parameters such as insulation
thickness, spacing, material types, geometry of winding and slot are
major design consideration. A very powerful method available to
analyze electro thermal performance is Finite Element Method
(FEM) which is used in this paper. The analysis of various stator coil
and slot configurations are used to design the better dielectric system
to reduce electrical and thermal stresses in order to increase the
power of generator in the same volume of core. This paper describes
the process used to perform classical design and improvement
analysis of stator slot-s insulation.
Abstract: The recurring decimal of rural and urban poverty in
Nigeria, resulting from lack of sustainable livelihood activities by
the people due to non-diversification of the economy, necessitated
this study. One hundred snail farmers were randomly selected in
Akure North and Akure South Local Government areas of Ondo
State, Southwest Nigeria where snail farming is widely practised.
Data collection was through questionnaires administration and onsite
observation of farms. Data obtained were subjected to
descriptive statistics, Student-s t-test and regression analysis. Cost
benefit ratio (CBR) and rate of return on investment (RORI) were
calculated in order to determine the poverty alleviation potentials of
snail farming in the study areas. Although snail farming was
profitable and viable, it was below poverty line. With time and more
knowledge in its farming activities, and with more people taking to
snail production, its poverty alleviation and reduction potentials will
increase.
Abstract: Discrimination in employment has its wider social and
economic consequences other than mere violating a basic human
right. Discrimination involves treating people differently because of
certain grounds such as race, color, or sex, which results in the
impairment of equality of opportunity and treatment. As an essential
part of promoting decent work, combating discrimination through the
principle of non-discrimination has been established by the
International Labor Organization (ILO) through the Declaration on
Fundamental Principles and Rights at Work 1998. Considering
elimination of discrimination in employment as a core labor standard,
member states are expected to respect, promote and implement it to
their national laws and policies. Being a member state, Malaysia has
to position herself align with this international requirement. The
author discusses the related convention together with Malaysia-s
responses on the matter. At the closing stage, the prospect of
Malaysia is presumed taking into account of the current positions and
reports submitted to the ILO.
Abstract: Polymers are one of the most widely used materials in our every day life. The subject of renewable resources has attracted great attention in the last period of time. New polymeric materials derived from renewable resources, like carbohydrates draw attention to public eye especially because of their biocompatibility and biodegradability. The aim of our paper was to obtain environmentally compatible polymers from monosaccharides. Novel glycopolymers based on D-glucose have been obtained from copolymerization of a new monomer carrying carbohydrate moiety with methyl methacrylate (MMA) via free radical bulk polymerization. Differential scanning calorimetry (DSC) was performed in order to study the copolymerization process of the monomer into the chosen co-monomer; the activation energy of this process was evaluated using Ozawa method. The copolymers obtained were characterized using ATR-FTIR spectroscopy. The thermal stability of the obtained products was studied by thermogravimetry (TG).
Abstract: The goal of this paper is to find Wardrop equilibrium
in transport networks at case of uncertainty situations, where the
uncertainty comes from lack of information. We use simulation tool
to find the equilibrium, which gives only approximate solution, but
this is sufficient for large networks as well. In order to take the
uncertainty into account we have developed an interval-based
procedure for finding the paths with minimal cost using the
Dempster-Shafer theory. Furthermore we have investigated the users-
behaviors using game theory approach, because their path choices
influence the costs of the other users- paths.
Abstract: The zero inflated models are usually used in modeling
count data with excess zeros where the existence of the excess zeros
could be structural zeros or zeros which occur by chance. These type
of data are commonly found in various disciplines such as finance,
insurance, biomedical, econometrical, ecology, and health sciences
which involve sex and health dental epidemiology. The most popular
zero inflated models used by many researchers are zero inflated
Poisson and zero inflated negative binomial models. In addition, zero
inflated generalized Poisson and zero inflated double Poisson models
are also discussed and found in some literature. Recently zero
inflated inverse trinomial model and zero inflated strict arcsine
models are advocated and proven to serve as alternative models in
modeling overdispersed count data caused by excessive zeros and
unobserved heterogeneity. The purpose of this paper is to review
some related literature and provide a variety of examples from
different disciplines in the application of zero inflated models.
Different model selection methods used in model comparison are
discussed.
Abstract: The volume of biosolids produced in Malaysia
nowadays had increased proportionally to its population size. The end
products from the waste treatments were mounting, thus inevitable
that in the end the environment will be surrounded by the waste. This
study was conducted to investigate the suitability of biosolids to be
reused as fertilizer for non-food crop. By varying the concentration of
biosolids applied onto the soil, growth of five ornamental plant
samples were tested for eight consecutive weeks. The results show
that the pH of the soil after the addition of biosolids ranges from 6.45
to 6.56 which is suitable for the plant growth. The soil samples that
contains biosolid also show higher amount of macronutrients (N, P,
K) and the heavy metals content are significantly increased in the
plant however it does not exceed the guidelines drawn by the
Environmental Protection Agency. It is also proven that there was
only small significant different in the performance of plant growth
between biosolids and commercial fertilizer. It can be seen that
biosolids was able to perform just as well as commercial fertilizer.
Abstract: Commercial nanocomposite food packaging type nano-silver containers were characterised using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The presence of nanoparticles consistent with the incorporation of 1% nano-silver (Ag) and 0.1% titanium dioxide (TiO2) nanoparticle into polymeric materials formed into food containers was confirmed. Both nanomaterials used in this type of packaging appear to be embedded in a layered configuration within the bulk polymer. The dimensions of the incorporated nanoparticles were investigated using X-ray diffraction (XRD) and determined by calculation using the Scherrer Formula; these were consistent with Ag and TiO2 nanoparticles in the size range 20-70nm both were spherical shape nanoparticles. Antimicrobial assessment of the nanocomposite container has also been performed and the results confirm the antimicrobial activity of Ag and TiO2 nanoparticles in food packaging containers. Migration assessments were performed in a wide range of food matrices to determine the migration of nanoparticles from the packages. The analysis was based upon the relevant European safety Directives and involved the application of inductively coupled plasma mass spectrometry (ICP-MS) to identify the range of migration risk. The data pertain to insignificance levels of migration of Ag and TiO2 nanoparticles into the selected food matrices.
Abstract: This study applies the sequential panel selection
method (SPSM) procedure proposed by Chortareas and Kapetanios
(2009) to investigate the time-series properties of energy
consumption in 50 US states from 1963 to 2009. SPSM involves the
classification of the entire panel into a group of stationary series and
a group of non-stationary series to identify how many and which
series in the panel are stationary processes. Empirical results obtained
through SPSM with the panel KSS unit root test developed by Ucar
and Omay (2009) combined with a Fourier function indicate that
energy consumption in all the 50 US states are stationary. The results
of this study have important policy implications for the 50 US states.
Abstract: This paper presents the review of past studies
concerning mathematical models for rescheduling passenger railway
services, as part of delay management in the occurrence of railway
disruption. Many past mathematical models highlighted were aimed
at minimizing the service delays experienced by passengers during
service disruptions. Integer programming (IP) and mixed-integer
programming (MIP) models are critically discussed, focusing on the
model approach, decision variables, sets and parameters. Some of
them have been tested on real-life data of railway companies
worldwide, while a few have been validated on fictive data. Based
on selected literatures on train rescheduling, this paper is able to
assist researchers in the model formulation by providing
comprehensive analyses towards the model building. These analyses
would be able to help in the development of new approaches in
rescheduling strategies or perhaps to enhance the existing
rescheduling models and make them more powerful or more
applicable with shorter computing time.
Abstract: In vitro plant regeneration has been successfully obtained from basal shoot explant of Vetiveria zizanioides through indirect organogenesis. The explant was cultured in Murashige & Skoog’s (MS) media supplemented with 2,4-D, IAA, and kinetin in various concentrations. Callus was well induced in media supplemented with 2 ppm 2,4-D, 1 ppm IAA, and 1 ppm kinetin. This callus was then transferred to MS media supplemented with 1 - 5 ppm of BAP for shoot regeneration. The media supplemented with 3 ppm BAP was a suitable medium for shoot induction, as well as for shoot multiplication. Rooting was well developed in shoot following transferred to half MS media containing 0.2 ppm IBA. Plantlet was then transferred to husk charcoal for acclimatization, and almost all (90%) of plantlets were survived during acclimatization.
Abstract: Interactive public displays give access as an
innovative media to promote enhanced communication between
people and information. However, digital public displays are subject
to a few constraints, such as content presentation. Content
presentation needs to be developed to be more interesting to attract
people’s attention and motivate people to interact with the display. In
this paper, we proposed idea to implement contents with interaction
elements for vision-based digital public display. Vision-based
techniques are applied as a sensor to detect passers-by and theme
contents are suggested to attract their attention for encouraging them
to interact with the announcement content. Virtual object, gesture
detection and projection installation are applied for attracting
attention from passers-by. Preliminary study showed positive
feedback of interactive content designing towards the public display.
This new trend would be a valuable innovation as delivery of
announcement content and information communication through this
media is proven to be more engaging.
Abstract: This paper presents the exergy analysis of a
desalination unit using humidification-dehumidification process.
Here, this unit is considered as a thermal system with three main
components, which are the heating unit by using a solar collector, the
evaporator or the humidifier, and the condenser or the dehumidifier.
In these components the exergy is a measure of the quality or grade
of energy and it can be destroyed in them. According to the second
law of thermodynamics this destroyed part is due to irreversibilities
which must be determined to obtain the exergetic efficiency of the
system.
In the current paper a computer program has been developed using
visual basic to determine the exergy destruction and the exergetic
efficiencies of the components of the desalination unit at variable
operation conditions such as feed water temperature, outlet air
temperature, air to feed water mass ratio and salinity, in addition to
cooling water mass flow rate and inlet temperature, as well as
quantity of solar irradiance.
The results obtained indicate that the exergy efficiency of the
humidifier increases by increasing the mass ratio and decreasing the
outlet air temperature. In the other hand the exergy efficiency of the
condenser increases with the increase of this ratio and also with the
increase of the outlet air temperature.
Abstract: Suburban area is an important area to the development of a city and a country. Russias economy is going through major transitions. These transitions are rapidly changing the relationship between cities (urban areas), countryside (rural areas) and the development, growth, and popularity of suburbia. The process of suburbanization takes place in biggest cities of Russia, including Krasnoyarsk City. The modern Krasnoyarsk with a population of about 1mln people occupies the territory of 34115 ha. This article examines the analysis of functions of suburban area and connects these functions with zoning of the suburban territory. The author uses the method of hierarchy to select the best conditions to each function in connection with nature component, transportation and distance from the city. The result of this research is the map of the functional zoning of suburban area of Krasnoyarsk City. The author uses a variety of factors, which have an influence on suburban area, to compare and choose the best conditions. KeywordsSuburban area, zoning of territory, Krasnoyarsk City.
Abstract: A study was carried out at the Rice Research Institute of Iran (RRII) to investigate the effect of rollers differential peripheral speed of commercial rubber roll husker and paddy moisture content on the husking index and percentage of broken rice. The experiment was conducted at six levels of rollers differential speed (1.5, 2.2, 2.9, 3.6, 4.3 and 5 m/s) and three levels of paddy moisture content (8-9, 10-11 and 12-13% w.b.). Two common paddy varieties namely, Binam and Khazer, were selected for this study. Results revealed that the effect of rollers differential speed and moisture content significantly (P
Abstract: In this paper, experimental testing and numerical analysis were used to investigate the effect of tube thickness on the face bending for concrete filled hollow sections connected to other structural members using Extended Hollobolts. Six samples were tested experimentally by applying pull-out load on the bolts. These samples were designed to fail by column face bending. The main variable in all tests is the column face thickness. Finite element analyses were also performed using ABAQUS 6.11 to extend the experimental results and to quantify the effect of column face thickness. Results show that, the column face thickness has a clear impact on the connection strength and stiffness. However, the amount of improvement in the connection stiffness by changing the column face thickness from 5mm to 6.3mm seems to be higher than that when increasing it from 6.3mm to 8mm. The displacement at which the bolts start pulling-out from their holes increased with the use of thinner column face due to the high flexibility of the section. At the ultimate strength, the yielding of the column face propagated to the column corner and there was no yielding in its walls. After the ultimate resistance is reached, the propagation of the yielding was mainly in the column face with a miner yielding in the walls.