Abstract: Load balancing is the process of improving the
performance of a parallel and distributed system through a
redistribution of load among the processors [1] [5]. In this paper we
present the performance analysis of various load balancing
algorithms based on different parameters, considering two typical
load balancing approaches static and dynamic. The analysis indicates
that static and dynamic both types of algorithm can have
advancements as well as weaknesses over each other. Deciding type
of algorithm to be implemented will be based on type of parallel
applications to solve. The main purpose of this paper is to help in
design of new algorithms in future by studying the behavior of
various existing algorithms.
Abstract: In this paper, we consider Wiener nonlinear model for solid oxide fuel cell (SOFC). The Wiener model of the SOFC consists of a linear dynamic block and a static output non-linearity followed by the block, in which linear part is approximated by state-space model and the nonlinear part is identified by a polynomial form. To control the SOFC system, we have to consider various view points such as operating conditions, another constraint conditions, change of load current and so on. A change of load current is the significant one of these for good performance of the SOFC system. In order to keep the constant stack terminal voltage by changing load current, the nonlinear model predictive control (MPC) is proposed in this paper. After primary control method is designed to guarantee the fuel utilization as a proper constant, a nonlinear model predictive control based on the Wiener model is developed to control the stack terminal voltage of the SOFC system. Simulation results verify the possibility of the proposed Wiener model and MPC method to control of SOFC system.
Abstract: In this study, a 3D combustion chamber was simulated
using FLUENT 6.32. Aims to obtain accurate information about the
profile of the combustion in the furnace and also check the effect of
oxygen enrichment on the combustion process. Oxygen enrichment is
an effective way to reduce combustion pollutant. The flow rate of air
to fuel ratio is varied as 1.3, 3.2 and 5.1 and the oxygen enriched
flow rates are 28, 54 and 68 lit/min. Combustion simulations
typically involve the solution of the turbulent flows with heat
transfer, species transport and chemical reactions. It is common to
use the Reynolds-averaged form of the governing equation in
conjunction with a suitable turbulence model. The 3D Reynolds
Averaged Navier Stokes (RANS) equations with standard k-ε
turbulence model are solved together by Fluent 6.3 software. First
order upwind scheme is used to model governing equations and the
SIMPLE algorithm is used as pressure velocity coupling. Species
mass fractions at the wall are assumed to have zero normal
gradients.Results show that minimum mole fraction of CO2 happens
when the flow rate ratio of air to fuel is 5.1. Additionally, in a fixed
oxygen enrichment condition, increasing the air to fuel ratio will
increase the temperature peak. As a result, oxygen-enrichment can
reduce the CO2 emission at this kind of furnace in high air to fuel
rates.
Abstract: Aroma forming volatiles are important components of
fermented beverages. The aim of current research is to evaluate the
volatile compounds and phenolic compounds of commercial ciders.
Volatile aroma compounds and TPC of seven commercial ciders
were determined. Extraction of aroma compounds was performed
using solid phase microextraction (DVB/Car/PDMS fibre). Analysis
of volatile aroma compounds was made using a Perkin Elmer Clarus
500 GC/MS. Total phenol content (TPC) was determined according
to the Folin-Ciocalteu spectrophotometric method and results were
expressed as gallic acid equivalents. The highest volatile compounds
were in apple ciders with pear flavor. The highest TPC and lower
content of volatile compounds were detected in French ciders.
Abstract: The fast technology and economic growth in China has
attracted global attention in its tourism development. This study makes
an effort on investigating China-s online tourism market and the
Chinese online travelers- perceptions of hotel websites. The findings
are expected to better understand Chinese customers- online
preference and identified the differences among online travelers from
different regions in the country. Empirical findings showed online
reservation information is the most important factor to Chinese
customers, and tourists from different regions of China have
perception difference on user-friendly factor. The findings benefit
hoteliers from understanding their websites development and
formulating more appropriate online strategies to meet the
requirements of Chinese travelers.
Abstract: This study was carried out to determine the feedback from the primary school headmasters on in-service training activities. 384 primary school headmasters were asked to give feedback on the in-service training facilities organized by the Ministry of Education through an open –ended question. The study group was formed by 359 primary school headmasters who attended “Management Skills" seminars which were organized in March, April and May in the extent of 2006 In-service Training Facilities Plan by the Ministry of Education and were also volunteers to give feedback on the inservice training activities. The qualitative research method was used in the analysis of the data since the primary school headmasters gave written feedback on the in-service training activities. Having analyzed the feedback, certain categories were formed by coding it. Certain frequencies and percentages were determined according to the codes. It was made obvious that the primary school headmasters benefitted from those facilities by sharing their experiences, problems and their possible solutions mutually
Abstract: Functional Magnetic Resonance Imaging(fMRI) is a
noninvasive imaging technique that measures the hemodynamic
response related to neural activity in the human brain. Event-related
functional magnetic resonance imaging (efMRI) is a form of
functional Magnetic Resonance Imaging (fMRI) in which a series of
fMRI images are time-locked to a stimulus presentation and averaged
together over many trials. Again an event related potential (ERP) is a
measured brain response that is directly the result of a thought or
perception. Here the neuronal response of human visual cortex in
normal healthy patients have been studied. The patients were asked
to perform a visual three choice reaction task; from the relative
response of each patient corresponding neuronal activity in visual
cortex was imaged. The average number of neurons in the adult
human primary visual cortex, in each hemisphere has been estimated
at around 140 million. Statistical analysis of this experiment was
done with SPM5(Statistical Parametric Mapping version 5) software.
The result shows a robust design of imaging the neuronal activity of
human visual cortex.
Abstract: This study examines the influence of information
transparency and corporate governance on purchase directors and
officers liability (D&O) insurance decisions. The results show that
companies with greater information transparency have significant
demand for D&O insurance. Greater transparency in voluntary
disclosures is significantly and positively associated with demand for
insurance, indicating that increasing the degree of information
disclosure reduces information asymmetry for insurers, which
stimulates their willingness to provide greater protection.
Analysis of insured and uninsured subsamples indicates that
uninsured companies have superior corporate governance compared to
insured companies. Although insured companies tend to have weaker
corporate governance structures, they appoint Big 4 firms or industry
experts to compensate for the weakness of their corporate governance.
Empirical results indicate that purchasing D&O insurance can
strengthen external corporate governance and increase companies’
willingness to voluntarily provide more transparent information.
Abstract: This paper presents the experimental results of
leakage current waveforms which appears on porcelain insulator
surface due to existence of artificial pollutants. The tests have been
done using the chemical compounds of NaCl, Na2SiO3, H2SO4, CaO,
Na2SO4, KCl, Al2SO4, MgSO4, FeCl3, and TiO2. The insulator
surface was coated with those compounds and dried. Then, it was
tested in the chamber where the high voltage was applied. Using
correspondence analysis, the result indicated that the fundamental
harmonic of leakage current was very close to the applied voltage
and third harmonic leakage current was close to the yielded leakage
current amplitude. The first harmonic power was correlated to first
harmonic amplitude of leakage current, and third harmonic power
was close to third harmonic one. The chemical compounds of H2SO4
and Na2SiO3 affected to the power factor of around 70%. Both are the
most conductive, due to the power factor drastically increase among
the chemical compounds.
Abstract: An improved processing description to be employed in biosonar signal processing in a cochlea model is proposed and examined. It is compared to conventional models using a modified discrimination analysis and both are tested. Their performances are evaluated with echo data captured from natural targets (trees).Results indicate that the phase characteristics of low-pass filters employed in the echo processing have a significant effect on class separability for this data.
Abstract: Application of projective geometry to the theory of two-ports and cascade circuits with a load change is considered. The equations linking the input and output of a two-port are interpreted as projective transformations which have the invariant as a cross-ratio of four points. This invariant has place for all regime parameters in all parts of a cascade circuit. This approach allows justifying the definition of a regime and its change, to calculate a circuit without explicitly finding the aparameters, to transmit accurately an analogue signal through the unstable two-port.
Abstract: In order to improve the simulation effects of space cold
black environment, this paper described a rectangular channel plate
heat sink. By using fluid mechanics theory and finite element method,
the internal fluid flow and heat transfer in heat sink was numerically
simulated to analyze the impact of channel structural on fluid flow and
heat transfer. The result showed that heat sink temperature uniformity
is well, and the impact of channel structural on the heat sink
temperature uniformity is not significant. The channel depth and
spacing are important factors which affect the fluid flow and heat
transfer in the heat sink. The two factors of heat transfer and resistance
need to be considered comprehensively to determine the optimal flow
structure parameters.
Abstract: In this paper we introduce an efficient solution
method for the Eigen-decomposition of bisymmetric and per
symmetric matrices of symmetric structures. Here we decompose
adjacency and Laplacian matrices of symmetric structures to submatrices
with low dimension for fast and easy calculation of
eigenvalues and eigenvectors. Examples are included to show the
efficiency of the method.
Abstract: Mammography is the most effective procedure for an
early diagnosis of the breast cancer. Nowadays, people are trying to
find a way or method to support as much as possible to the
radiologists in diagnosis process. The most popular way is now being
developed is using Computer-Aided Detection (CAD) system to
process the digital mammograms and prompt the suspicious region to
radiologist. In this paper, an automated CAD system for detection
and classification of massive lesions in mammographic images is
presented. The system consists of three processing steps: Regions-Of-
Interest detection, feature extraction and classification. Our CAD
system was evaluated on Mini-MIAS database consisting 322
digitalized mammograms. The CAD system-s performance is
evaluated using Receiver Operating Characteristics (ROC) and Freeresponse
ROC (FROC) curves. The archived results are 3.47 false
positives per image (FPpI) and sensitivity of 85%.
Abstract: As privacy becomes a major concern for consumers
and enterprises, many research have been focused on the privacy
protecting technology in recent years. In this paper, we present a
comprehensive approach for usage access control based on the notion
purpose. In our model, purpose information associated with a given
data element specifies the intended use of the subjects and objects in
the usage access control model. A key feature of our model is that it
allows when an access is required, the access purpose is checked
against the intended purposes for the data item. We propose an
approach to represent purpose information to support access control
based on purpose information. Our proposed solution relies on usage
access control (UAC) models as well as the components which based
on the notions of the purpose information used in subjects and
objects. Finally, comparisons with related works are analyzed.
Abstract: Employee-s task performance has been recognized as a
core contributor to overall organizational effectiveness. Hence,
verifying the determinants of task performance is one of the most
important research issues. This study tests the influence of perceived
organizational support, abusive supervision, and exchange ideology
on employee-s task performance. We examined our hypotheses by
collecting self-reported data from 413 Korean employees in different
organizations. Our all hypotheses gained support from the results.
Implications for research and directions for future research are
discussed.
Abstract: Osteoarthritis (OA) is the most prevalent and far common debilitating form of arthritis which can be defined as a degenerative condition affecting synovial joint. Patients suffering from osteoarthritis often complain of dull ache pain on movement.
Physical agents can fight the painful process when correctly indicated and used such as heat or cold therapy Aim. This study was carried out to: Compare the effect of cold, warm and contrast therapy on controlling knee osteoarthritis associated problems. Setting: The study was carried out in orthopedic outpatient clinics of Menoufia University and teaching Hospitals, Egypt. Sample: A convenient sample of 60 adult patients with unilateral knee osteoarthritis. Tools: three tools were utilized to collect the data. Tool I : An interviewing questionnaire. It comprised of three parts covering sociodemographic data, medical data and adverse effects of the treatment protocol. Tool II : Knee Injury and Osteoarthritis Outcome Score (KOOS) It consists of five main parts. Tool II1 : 0-10 Numeric pain rating scale. Results: reveled that the total knee symptoms score was decreased from moderate symptoms pre intervention to mild symptoms after warm and contrast method of therapy, but the contrast therapy had significant effect in reducing the knee symptoms and pain than the other symptoms. Conclusions: all of the three
methods of therapy resulted in improvement in all knee symptoms and pain but the most appropriate protocol of treatment to relive symptoms and pain was contrast therapy.
Abstract: Economic dispatch problem is an optimization problem where objective function is highly non linear, non-convex, non-differentiable and may have multiple local minima. Therefore, classical optimization methods may not converge or get trapped to any local minima. This paper presents a comparative study of four different evolutionary algorithms i.e. genetic algorithm, bacteria foraging optimization, ant colony optimization and particle swarm optimization for solving the economic dispatch problem. All the methods are tested on IEEE 30 bus test system. Simulation results are presented to show the comparative performance of these methods.
Abstract: In this paper, a new algorithm for generating codebook is proposed for vector quantization (VQ) in image coding. The significant features of the training image vectors are extracted by using the proposed Orthogonal Polynomials based transformation. We propose to generate the codebook by partitioning these feature vectors into a binary tree. Each feature vector at a non-terminal node of the binary tree is directed to one of the two descendants by comparing a single feature associated with that node to a threshold. The binary tree codebook is used for encoding and decoding the feature vectors. In the decoding process the feature vectors are subjected to inverse transformation with the help of basis functions of the proposed Orthogonal Polynomials based transformation to get back the approximated input image training vectors. The results of the proposed coding are compared with the VQ using Discrete Cosine Transform (DCT) and Pairwise Nearest Neighbor (PNN) algorithm. The new algorithm results in a considerable reduction in computation time and provides better reconstructed picture quality.
Abstract: The aim of this work is to determine the supersonic
nozzle profiles used in propulsion, for the launchers or embarked
with the satellites. This design has as a role firstly, to give a
important propulsion, i.e. with uniform and parallel flow at exit,
secondly to find a short length profiles without modification of the
flow in the nozzle. The first elaborate program is used to determine
the profile of divergent by using the characteristics method for an
axisymmetric flow. The second program is conceived by using the
finite volume method to determine and test the profile found
connected to a convergent.