Abstract: This paper investigates the effects of knowledge-based acceleration feedback control integrated with Automatic Generation Control (AGC) to enhance the quality of frequency control of governing system. The Intelligent Acceleration Feedback Controller (IAFC) is proposed to counter the over and under frequency occurrences due to major load change in power system network. Therefore, generator tripping and load shedding operations can be reduced. Meanwhile, the integration of IAFC with AGC, a well known Load-Frequency Control (LFC) is essential to ensure the system frequency is restored to the nominal value. Computer simulations of frequency response of governing system are used to optimize the parameters of IAFC. As a result, there is substantial improvement on the LFC of governing system that employing the proposed control strategy.
Abstract: This paper treats a discrete-time finite buffer batch arrival queue with a single working vacation and partial batch rejection in which the inter-arrival and service times are, respectively, arbitrary and geometrically distributed. The queue is analyzed by using the supplementary variable and the imbedded Markov-chain techniques. We obtain steady-state system length distributions at prearrival, arbitrary and outside observer-s observation epochs. We also present probability generation function (p.g.f.) of actual waiting-time distribution in the system and some performance measures.
Abstract: The paper presents an optimization study based on
genetic algorithms (GA-s) for a radio-frequency applicator used in
heating dielectric band products. The weakly coupled electro-thermal
problem is analyzed using 2D-FEM. The design variables in the
optimization process are: the voltage of a supplementary “guard"
electrode and six geometric parameters of the applicator. Two
objective functions are used: temperature uniformity and total active
power absorbed by the dielectric. Both mono-objective and multiobjective
formulations are implemented in GA optimization.
Abstract: Our objectives were to evaluate the effects of sire
breed, type of protein supplement, level of supplementation and sex
on wool spinning fineness (SF), its correlations with other wool
characteristics and prediction accuracy in F1 Merino crossbred lambs.
Texel, Coopworth, White Suffolk, East Friesian and Dorset rams
were mated with 500 purebred Merino dams at a ratio of 1:100 in
separate paddocks within a single management system. The F1
progeny were raised on ryegrass pasture until weaning, before forty
lambs were randomly allocated to treatments in a 5 x 2 x 2 x 2
factorial experimental design representing 5 sire breeds, 2
supplementary feeds (canola or lupins), 2 levels of supplementation
(1% or 2% of liveweight) and sex (wethers or ewes). Lambs were
supplemented for six weeks after an initial three weeks of adjustment,
wool sampled at the commencement and conclusion of the feeding
trial and analyzed for SF, mean fibre diameter (FD), coefficient of
variation (CV), standard deviation, comfort factor (CF), fibre
curvature (CURV), and clean fleece yield. Data were analyzed using
mixed linear model procedures with sire fitted as a random effect,
and sire breed, sex, supplementary feed type, level of
supplementation and their second-order interactions as fixed effects.
Sire breed (P
Abstract: This paper treats a discrete-time batch arrival queue with single working vacation. The main purpose of this paper is to present a performance analysis of this system by using the supplementary variable technique. For this purpose, we first analyze the Markov chain underlying the queueing system and obtain its ergodicity condition. Next, we present the stationary distributions of the system length as well as some performance measures at random epochs by using the supplementary variable method. Thirdly, still based on the supplementary variable method we give the probability generating function (PGF) of the number of customers at the beginning of a busy period and give a stochastic decomposition formulae for the PGF of the stationary system length at the departure epochs. Additionally, we investigate the relation between our discretetime system and its continuous counterpart. Finally, some numerical examples show the influence of the parameters on some crucial performance characteristics of the system.
Abstract: This paper presents a systematic approach for designing Unified Power Flow Controller (UPFC) based supplementary damping controllers for damping low frequency oscillations in a single-machine infinite-bus power system. Detailed investigations have been carried out considering the four alternatives UPFC based damping controller namely modulating index of series inverter (mB), modulating index of shunt inverter (mE), phase angle of series inverter (δB ) and phase angle of the shunt inverter (δE ). The design problem of the proposed controllers is formulated as an optimization problem and Real- Coded Genetic Algorithm (RCGA) is employed to optimize damping controller parameters. Simulation results are presented and compared with a conventional method of tuning the damping controller parameters to show the effectiveness and robustness of the proposed design approach.
Abstract: Many studies have emphasized the importance of
resistive exercise to maintain a healthy human body, particular in
prevention of weakening of physical strength. Recently, some studies
advocated that an application of vibration as a supplementary means in
a regular training was effective in encouraging physical strength. Aim
of the current study was, therefore, to identify if an application of
vibration in a resistive exercise was effective in encouraging physical
strength as that in a regular training. A 3-dimensional virtual lower
extremity model for a healthy male and virtual leg-press model were
generated and synchronized. Dynamic leg-press exercises on a slide
machine with/without extra load and on a footboard with vibration as
well as on a slide machine with extra load were analyzed. The results
of the current indicated that the application of the vibration on the
dynamic leg-press exercise might be not greatly effective in
encouraging physical strength, compared with the dynamic leg press
exercise with extra load. It was, however, thought that the application
of the vibration might be helpful to elderly individuals because the
reduced maximum muscle strength appeared by the effect of the
vibration may avoid a muscular spasm, which can be driven from a
high muscle strength sometimes produced during the leg-press
exercise with extra load.
Abstract: Dew harvesting needs only weak investment and
exploits a free, clean and inexhaustible energy. This study aims to
measure the relative contributions of dew and rain water in the
Mediterranean Dalmatian coast and islands of Croatia and determine
whether dew water is potable. Two sites were chosen, an open site on
the coast favourable to dew formation (Zadar) and a less favourable
site in a circus of mountains in Komiža (Vis Island). Between July
1st, 2003 and October 31st, 2006, dew hasbeen daily collected on a 1
m2 tilted (30°) test dew condenser together with ordinary
meteorological data (air temperature and relative humidity, cloud
coverage, windspeed and direction). The mean yearly cumulative
dew yields were found to be 20 mm (Zadar) and 9.3 mm (Komiža ).
During the dry season (May to October), monthly cumulative dew
water yield can represent up to 38% of water collected by rain fall. In
July 2003 and 2006, dew water represented about 120% of the
monthly cumulative rain water. Dew and rain water were analyzed in
Zadar. The corresponding parameters were measured: pH, electrical
conductivity, major anions (HCO3
-, Cl-, SO4
2-
, NO3
-
, ,) and major
cations (NH4
+, Na+, K+, Ca2+, Mg2+. Both dew and rain water are in
conformity with the WHO directives for potability except Mg2+.
Using existing roofs and refurbishing the abandoned impluviums to
permit dew collection could then provide a useful supplementary
amount of water, especially during the dry season.
Abstract: The current study has investigated the ageing
phenomena of silica optical fibres in relation to water activity which might be accelerated when exposed to a supplementary energy, such as microwaves. A controlled stress by winding fibres onto accurate
diameter mandrel was applied. Taking into account that normally a
decrease in fibre strength is induced in time by chemical action of water, the effects of cumulative reagents such as: water, applied stress and supplementary energy (microwave) in some cases acted in
the opposite manner. The microwave effect as a structural relaxation
catalyst appears unexpected, even if the overall gain in fibre strength is not high, but the stress corrosion factor revealed significant
increase in certain simulation conditions.
Abstract: Many real-world optimization problems involve multiple conflicting objectives and the use of evolutionary algorithms to solve the problems has attracted much attention recently. This paper investigates the application of multi-objective optimization technique for the design of a Thyristor Controlled Series Compensator (TCSC)-based controller to enhance the performance of a power system. The design objective is to improve both rotor angle stability and system voltage profile. A Genetic Algorithm (GA) based solution technique is applied to generate a Pareto set of global optimal solutions to the given multi-objective optimisation problem. Further, a fuzzy-based membership value assignment method is employed to choose the best compromise solution from the obtained Pareto solution set. Simulation results are presented to show the effectiveness and robustness of the proposed approach.
Abstract: In this research study, an intelligent detection system
to support medical diagnosis and detection of abnormal lesions by
processing endoscopic images is presented. The images used in this
study have been obtained using the M2A Swallowable Imaging
Capsule - a patented, video color-imaging disposable capsule.
Schemes have been developed to extract texture features from the
fuzzy texture spectra in the chromatic and achromatic domains for a
selected region of interest from each color component histogram of
endoscopic images. The implementation of an advanced fuzzy
inference neural network which combines fuzzy systems and
artificial neural networks and the concept of fusion of multiple
classifiers dedicated to specific feature parameters have been also
adopted in this paper. The achieved high detection accuracy of the
proposed system has provided thus an indication that such intelligent
schemes could be used as a supplementary diagnostic tool in
endoscopy.
Abstract: A water reuse system in wetland paddy was simulated
to supply water for industrial in this paper. A two-tank model was employed to represent the return flow of the wetland paddy.Historical data were performed for parameter estimation and model verification. With parameters estimated from the data, the model was then used to simulate a reasonable return flow rate from the wetland
paddy. The simulation results show that the return flow ratio was 11.56% in the first crop season and 35.66% in the second crop
season individually; the difference may result from the heavy rainfall in the second crop season. Under the existent pond with surplus
active capacity, the water reuse ratio was 17.14%, and the water supplementary ratio was 21.56%. However, the pattern of rainfall, the
active capacity of the pond, and the rate of water treatment limit the
volume of reuse water. Increasing the irrigation water, dredging the
depth of pond before rainy season and enlarging the scale of module are help to develop water reuse system to support for the industrial
water use around wetland paddy.
Abstract: Mammographic images and data analysis to
facilitate modelling or computer aided diagnostic (CAD) software development should best be done using a common database that can handle various mammographic image file
formats and relate these to other patient information.
This would optimize the use of the data as both primary
reporting and enhanced information extraction of research data could be performed from the single dataset. One desired
improvement is the integration of DICOM file header information into the database, as an efficient and reliable source of supplementary patient information intrinsically
available in the images.
The purpose of this paper was to design a suitable database to link and integrate different types of image files and gather common information that can be further used for research
purposes. An interface was developed for accessing, adding,
updating, modifying and extracting data from the common
database, enhancing the future possible application of the data in CAD processing.
Technically, future developments envisaged include the creation of an advanced search function to selects image files
based on descriptor combinations. Results can be further used for specific CAD processing and other research. Design of a
user friendly configuration utility for importing of the required fields from the DICOM files must be done.
Abstract: The aim of this study was to remove the two principal
noises which disturb the surface electromyography signal
(Diaphragm). These signals are the electrocardiogram ECG artefact
and the power line interference artefact. The algorithm proposed
focuses on a new Lean Mean Square (LMS) Widrow adaptive
structure. These structures require a reference signal that is correlated
with the noise contaminating the signal. The noise references are
then extracted : first with a noise reference mathematically
constructed using two different cosine functions; 50Hz (the
fundamental) function and 150Hz (the first harmonic) function for
the power line interference and second with a matching pursuit
technique combined to an LMS structure for the ECG artefact
estimation. The two removal procedures are attained without the use
of supplementary electrodes. These techniques of filtering are
validated on real records of surface diaphragm electromyography
signal. The performance of the proposed methods was compared with
already conducted research results.
Abstract: Dynamic Causal Modeling (DCM) functional
Magnetic Resonance Imaging (fMRI) is a promising technique to
study the connectivity among brain regions and effects of stimuli
through modeling neuronal interactions from time-series
neuroimaging. The aim of this study is to study characteristics of a
mirror neuron system (MNS) in elderly group (age: 60-70 years old).
Twenty volunteers were MRI scanned with visual stimuli to study a
functional brain network. DCM was employed to determine the
mechanism of mirror neuron effects. The results revealed major
activated areas including precentral gyrus, inferior parietal lobule,
inferior occipital gyrus, and supplementary motor area. When visual
stimuli were presented, the feed-forward connectivity from visual
area to conjunction area was increased and forwarded to motor area.
Moreover, the connectivity from the conjunction areas to premotor
area was also increased. Such findings can be useful for future
diagnostic process for elderly with diseases such as Parkinson-s and
Alzheimer-s.
Abstract: This paper deals with the current space-vector
decomposition in three-phase, three-wire systems on the basis of
some case studies. We propose four components of the current spacevector
in terms of DC and AC components of the instantaneous
active and reactive powers. The term of supplementary useless
current vector is also pointed out. The analysis shows that the current
decomposition which respects the definition of the instantaneous
apparent power vector is useful for compensation reasons only if the
supply voltages are sinusoidal. A modified definition of the
components of the current is proposed for the operation under
nonsinusoidal voltage conditions.
Abstract: Static Var Compensator (SVC) is a shunt type FACTS
device which is used in power system primarily for the purpose of
voltage and reactive power control. In this paper, a fuzzy logic based
supplementary controller for Static Var Compensator (SVC) is
developed which is used for damping the rotor angle oscillations and
to improve the transient stability of the power system. Generator
speed and the electrical power are chosen as input signals for the
Fuzzy Logic Controller (FLC). The effectiveness and feasibility of
the proposed control is demonstrated with Single Machine Infinite
Bus (SMIB) system and multimachine system (WSCC System)
which show improvement over the use of a fixed parameter
controller.
Abstract: This study aims to screen out and to optimize the
major nutrients for maximum carotenoid production and
antioxidation characteristics by Rhodotorula rubra. It was found that
supplementary of 10 g/l glucose as carbon source, 1 g/l ammonium
sulfate as nitrogen source and 1 g/l yeast extract as growth factor in
the medium provided the better yield of carotenoid content of 30.39
μg/g cell dry weight the amount of antioxidation of Rhodotorula
rubra by DPPH, ABTS and MDA method were 1.463%, 34.21% and
34.09 μmol/l, respectively.
Abstract: With high speed vessels getting ever more sophisti-cated, travelling at higher and higher speeds and operating in With high speed vessels getting ever more sophisticated,
travelling at higher and higher speeds and operating in areas of
high maritime traffic density, training becomes of the highest priority
to ensure that safety levels are maintained, and risks are adequately
mitigated. Training onboard the actual craft on the actual route still
remains the most effective way for crews to gain experience. However,
operational experience and incidents during the last 10 years
demonstrate the need for supplementary training whether in the area
of simulation or man to man, man/ machine interaction. Training and
familiarisation of the crew is the most important aspect in preventing
incidents. The use of simulator, computer and web based training
systems in conjunction with onboard training focusing on critical
situations will improve the man machine interaction and thereby
reduce the risk of accidents. Today, both ship simulator and bridge
teamwork courses are now becoming the norm in order to improve
further emergency response and crisis management skills. One of the
main causes of accidents is the human factor. An efficient way to
reduce human errors is to provide high-quality training to the personnel
and to select the navigators carefully.areas of high maritime traffic density, training becomes of the highest priority to ensure that safety levels are maintained, and risks are adequately mitigated. Training onboard the actual craft on the actual route still remains the most effective way for crews to gain experience. How-ever, operational experience and incidents during the last 10 years demonstrate the need for supplementary training whether in the area of simulation or man to man, man/ machine interaction. Training and familiarisation of the crew is the most important aspect in preventing incidents. The use of simulator, computer and web based training systems in conjunction with onboard training focusing on critical situations will improve the man machine interaction and thereby reduce the risk of accidents. Today, both ship simulator and bridge teamwork courses are now becoming the norm in order to improve further emergency response and crisis management skills. One of the main causes of accidents is the human factor. An efficient way to reduce human errors is to provide high-quality training to the person-nel and to select the navigators carefully. KeywordsCBT - WBT systems, Human factors.
Abstract: Natural pozzolan (NP) is one of the potential
prehistoric alternative binders in the construction industry. It has
been investigated as cement replacement in ordinary concrete by
several researchers for many purposes. Various supplementary
cementitious materials (SCMs) such as fly ash, limestone dust and
silica fume are widely used in the production of SCC; however,
limited studies to address the effect of NP on the properties of SCC
are documented. The current research is composed of different SCC
paste and concrete mixtures containing different replacement levels
of local NP as an alternative SCM. The effect of volume of paste
containing different amounts of local NP related to W/B ratio and
cement content on SCC fresh properties was assessed. The variations
in the fresh properties of SCC paste and concrete represented by
slump flow (flowability) and the flow rate were determined and
discussed. The results indicated that the flow properties of SCC paste
and concrete mixtures, at their optimized superplasticizer dosages,
were affected by the binder content of local NP and the total volume
fraction of SCC paste.