Abstract: This paper examines long-range dependence or longmemory
of financial time series on the exchange rate data by the
fractional Brownian motion (fBm). The principle of spectral density
function in Section 2 is used to find the range of Hurst parameter (H)
of the fBm. If 0< H
Abstract: The productivity of software development is one of the major concerns for project managers. Given the increasing complexity of the software being developed and the concomitant rise in the typical project size, the productivity has not consistently improved. By analyzing the latest release of ISBSG data repository with 4106 projects ever developed, we report on the factors found to significantly influence productivity, and present an original model for the estimation of productivity during project design. We further illustrate that software development productivity has experienced irregular variations between the years 1995 and 2005. Considering the factors significant to productivity, we found its variations are primarily caused by the variations of average team size for the development and the unbalanced use of the less productive development language 3GL.
Abstract: For a quick and accurate calculation of spatial neutron
distribution in nuclear power reactors 3D nodal codes are usually
used aiming at solving the neutron diffusion equation for a given
reactor core geometry and material composition. These codes use a
second order polynomial to represent the transverse leakage term. In
this work, a nodal method based on the well known nodal expansion
method (NEM), developed at COPPE, making use of this polynomial
expansion was modified to treat the transverse leakage term for the
external surfaces of peripheral reflector nodes.
The proposed method was implemented into a computational
system which, besides solving the diffusion equation, also solves the
burnup equations governing the gradual changes in material
compositions of the core due to fuel depletion. Results confirm the
effectiveness of this modified treatment of peripheral nodes for
practical purposes in PWR reactors.
Abstract: Present study summarizes the control of Vibrio
alginolyticus infection in hatchery reared Clownfish, Amphiprion
sebae with the extract of the mangrove plant, Avicennia marina.
Fishes with visible symptoms of hemorrhagic spots were chosen and
the genomic DNA of the causative bacterium was isolated and
sequenced based on 16S rDNA gene. The in vitro assay revealed that
a fraction of A. marina leaf extract elucidated with ethyl acetate:
methanol (6:4) showed a high activity (28 mm) at 125 μg/ml
concentrations. About 4 % of the fraction fed along with live V.
alginolyticus was significantly decreased the cumulative mortality
(P
Abstract: This paper examines the problem of designing a robust H∞ filter for a class of uncertain fuzzy descriptor systems described by a Takagi-Sugeno (TS) fuzzy model. Based on a linear matrix inequality (LMI) approach, LMI-based sufficient conditions for the uncertain nonlinear descriptor systems to have an H∞ performance are derived. To alleviate the ill-conditioning resulting from the interaction of slow and fast dynamic modes, solutions to the problem are given in terms of linear matrix inequalities which are independent of the singular perturbation ε, when ε is sufficiently small. The proposed approach does not involve the separation of states into slow and fast ones and it can be applied not only to standard, but also to nonstandard uncertain nonlinear descriptor systems. A numerical example is provided to illustrate the design developed in this paper.
Abstract: As a by-product of its "cyberspace" status, electronic
commerce is global, encompassing a whole range of B2C
relationships which need to be approached with solutions provided at
a local level while remaining viable when applied to global issues.
Today, the European Union seems to be endowed with a reliable
legal framework for consumer protection. A question which remains,
however, is enforcement of this protection. This is probably a matter
of time and awareness from both parties in the B2C relationship.
Business should realize that enhancing trust in the minds of
consumers is more than a question of technology; it is a question of
best practice. Best practice starts with the online service of high
street banks as well as with the existence of a secure, user-friendly
and cost-effective payment system. It also includes the respect of
privacy and the use of smart cards as well as enhancing privacy
technologies and fair information practice. In sum, only by offering
this guarantee of privacy and security will the consumer be assured
that, in cyberspace, his/her interests will be protected in the same
manner as in a traditional commercial environment.
Abstract: recurrent neural network (RNN) is an efficient tool for
modeling production control process as well as modeling services. In
this paper one RNN was combined with regression model and were
employed in order to be checked whether the obtained data by the
model in comparison with actual data, are valid for variable process
control chart. Therefore, one maintenance process in workshop of
Esfahan Oil Refining Co. (EORC) was taken for illustration of
models. First, the regression was made for predicting the response
time of process based upon determined factors, and then the error
between actual and predicted response time as output and also the
same factors as input were used in RNN. Finally, according to
predicted data from combined model, it is scrutinized for test values
in statistical process control whether forecasting efficiency is
acceptable. Meanwhile, in training process of RNN, design of
experiments was set so as to optimize the RNN.
Abstract: This paper analyses the performance of a genetic algorithm using a new concept, namely a fractional-order dynamic fitness function, for the synthesis of combinational logic circuits. The experiments reveal superior results in terms of speed and convergence to achieve a solution.
Abstract: This text studies glass bottle intelligent inspector
based machine vision instead of manual inspection. The system
structure is illustrated in detail in this paper. The text presents the
method based on watershed transform methods to segment the
possible defective regions and extract features of bottle wall by rules.
Then wavelet transform are used to exact features of bottle finish
from images. After extracting features, the fuzzy support vector
machine ensemble is putted forward as classifier. For ensuring that
the fuzzy support vector machines have good classification ability,
the GA based ensemble method is used to combining the several
fuzzy support vector machines. The experiments demonstrate that
using this inspector to inspect glass bottles, the accuracy rate may
reach above 97.5%.
Abstract: Al-Murabahah is an Islamic financing facility used in
asset financing, the profit rate of the contract is determined by
components which are also being used in the conventional banking.
Such are cost of fund, overhead cost, risk premium cost and bank-s
profit margin. At the same time, the profit rate determined by Islamic
banking system also refers to Inter-Bank Offered Rate (LIBOR) in
London as a benchmark. This practice has risen arguments among
Muslim scholars in term of its validity of the contract; whether the
contract maintains the Shariah compliance or not. This paper aims to
explore the view of Shariah towards the above components practiced
by Islamic Banking in determining the profit rate of al-murabahah
asset financing in Malaysia. This is a comparative research which
applied the views of Muslim scholars from all major mazahibs in
Islamic jurisprudence and examined the practices by Islamic banks in
Malaysia for the above components. The study found that the shariah
accepts all the components with conditions. The cost of fund is
accepted as a portion of al-mudarabah-s profit, the overhead cost is
accepted as a cost of product, risk premium cost consist of business
risk and mitigation risk are accepted through the concept of alta-awun
and bank-s profit margin is accepted as a right of bank after
venturing in risky investment.
Abstract: This paper reports a new application of material accounting techniques to characterise and quantify material stocks and flows at the “neighbourhood" scale. The study area is the main campus of the University of New South Wales in Sydney, Australia. The system boundary is defined by the urban structural unit (USU), a typological construct devised to facilitate assessment of the metabolism of urban systems. A streamlined material flow analysis (MFA) was applied to quantify the stocks and flows of key construction materials within the campus USU over time, drawing on empirical data from a major campus development project. The results are reviewed to assess the efficacy of the method in supporting urban environmental evaluation and design practice, for example to facilitate estimation of significant impacts such as greenhouse gas emissions. It is concluded that linking a service (in this case, teaching students) enabled by a given product (university buildings) to the amount of materials used in creating that product offers a potential way to reduce the environmental impact of that service, through more efficient use of materials.
Abstract: A phenomenological model for species spreading which incorporates the Allee effect, a species- maximum attainable growth rate, collective dispersal rate and dispersal adaptability is presented. This builds on a well-established reaction-diffusion model for spatial spreading of invading organisms. The model is phrased in terms of the “hostility" (which quantifies the Allee threshold in relation to environmental sustainability) and dispersal adaptability (which measures how a species is able to adapt its migratory response to environmental conditions). The species- invading/retreating speed and the sharpness of the invading boundary are explicitly characterised in terms of the fundamental parameters, and analysed in detail.
Abstract: Chemical vapor deposition method was used to
produce carbon nanotubes on an iron based catalyst from acetylene.
Gas-phase samples collected from the different positions of the tubular reactor were analyzed by GC/MS. A variety of species ranging from hydrogen to naphthalene were observed and changes in their concentrations were plotted against the reactor position. Briefly benzene, toluene, styrene, indene and naphthalene were the main
higher molecular weight species and vinylacetylene and diacetylene were the important intermediates. Nanotube characterization was performed by scanning electron microscopy and transmission electron microscopy.
Abstract: The objective of this contribution is to study the
performances in terms of bit error rate, of space-time code algorithms
applied to MIMO communication in tunnels. Indeed, the channel
characteristics in a tunnel are quite different than those of urban or
indoor environment, due to the guiding effect of the tunnel.
Therefore, MIMO channel matrices have been measured in a straight
tunnel, in a frequency band around 3GHz. Correlation between array
elements and properties of the MIMO matrices are first studied as a
function of the distance between the transmitter and the receiver.
Then, owing to a software tool simulating the link, predicted values
of bit error rate are given for VLAST, OSTBC and QSTBC
algorithms applied to a MIMO configuration with 2 or 4 array
elements. Results are interpreted from the analysis of the channel
properties.
Abstract: In this work, we treat the problems related to chemical and petrochemical plants of a certain complex process taking the centrifugal compressor as an example, a system being very complex by its physical structure as well as its behaviour (surge phenomenon). We propose to study the application possibilities of the recent control approaches to the compressor behaviour, and consequently evaluate their contribution in the practical and theoretical fields. Facing the studied industrial process complexity, we choose to make recourse to fuzzy logic for analysis and treatment of its control problem owing to the fact that these techniques constitute the only framework in which the types of imperfect knowledge can jointly be treated (uncertainties, inaccuracies, etc..) offering suitable tools to characterise them. In the particular case of the centrifugal compressor, these imperfections are interpreted by modelling errors, the neglected dynamics, no modelisable dynamics and the parametric variations. The purpose of this paper is to produce a total robust nonlinear controller design method to stabilize the compression process at its optimum steady state by manipulating the gas rate flow. In order to cope with both the parameter uncertainty and the structured non linearity of the plant, the proposed method consists of a linear steady state regulation that ensures robust optimal control and of a nonlinear compensation that achieves the exact input/output linearization.
Abstract: The environmental performance of rapeseed oil (RO)
and rapeseed methyl ester(RME) from winter rape as fuels produced
in Romanian agroclimate is analyzed in this paper. The proposed
methodology is life cycle assessment (LCA) and takes into
consideration the influence of grain production and agroclimatic
conditions. This study shows favorable results first for RO and then
for RME. When compared to diesel fuel, both studied biofuels show
better results in the following impact categories: Abiotic depletion
potential (ADP), Ozone layer depletion (ODP) and Photochemical
ozone creation potential (POCP).Furthermore, the environmental
performance of the two biofuels studied can be improved by
changing the type of fertilizer used and also by using biofuels instead
of diesel in the field works.
Abstract: In this paper, the problem of finding the optimal
topological configuration of a deregulated distribution network is
considered. The new features of this paper are proposing a multiobjective
function and its application on deregulated distribution
networks for finding the optimal configuration. The multi-objective
function will be defined for minimizing total Energy Supply Costs
(ESC) and energy losses subject to load flow constraints. The
optimal configuration will be obtained by using Binary Genetic
Algorithm (BGA).The proposed method has been tested to analyze a
sample and a practical distribution networks.
Abstract: This paper describes a combined mathematicalgraphical
approach for optimum tool path planning in order to
improve machining efficiency. A methodology has been used that
stabilizes machining operations by adjusting material removal rate in
pocket milling operations while keeping cutting forces within limits.
This increases the life of cutting tool and reduces the risk of tool
breakage, machining vibration, and chatter. Case studies reveal the
fact that application of this approach could result in a slight increase
of machining time, however, a considerable reduction of tooling cost,
machining vibration, noise and chatter can be achieved in addition to
producing a better surface finish.
Abstract: The shelf life of fish was extended using disinfection
properties of ozone. For this purpose, Trout specimens were exposed
to ozone in the aqueous media for two hours and their microbial
growth and biochemical properties were measured over time.
Microbial growth of ozone treated fish was significantly slower than
control sample, resulting in lower counts of bacteria. According to
the biochemical tests; ozone treatment had no negative effects on fat,
protein and humidity of fish. Peroxide and TVN (Total Volatile
Nitrogen) measurements showed that treatment by ozone increased
the trout shelf life from 4 days to 6 days. According to the sensory
analysis, no changes were observed in color or flavor of the ozone
treated trout.
Abstract: As there has been a recognizable transition in
automotive industry from mass production to mass customization,
automobile manufacturers and their suppliers have been seeking ways
for more flexible and efficient processes. Eventually, modular
production is currently being applied to manage the changing orders of
the industry. In this paper, two different modular assembly line
concepts were studied: conveyor line and box assembly line.
Mathematical model for two assembly line concepts were developed
and their production line efficiency were compared as a performance
measure to improve their assembly line balancing.