Abstract: Even it has been recognized that Shape Memory
Alloys (SMA) have a significant potential for deployment actuators,
the number of applications of SMA-based actuators to the present
day is still quite small, due to the need of deep understanding of the
thermo-mechanical behavior of SMA, causing an important need for
a mathematical model able to describe all thermo-mechanical
properties of SMA by relatively simple final set of constitutive
equations. SMAs offer attractive potentials such as: reversible strains
of several percent, generation of high recovery stresses and high
power / weight ratios. The paper tries to provide an overview of the
shape memory functions and a presentation of the designed and
developed temperature control system used for a gripper actuated by
two pairs of differential SMA active springs. An experimental setup
was established, using electrical energy for actuator-s springs heating
process. As for holding the temperature of the SMA springs at certain
level for a long time was developed a control system in order to
avoid the active elements overheating.
Abstract: The main objective of this paper is to provide an efficient tool for delineating brain tumors in three-dimensional magnetic resonance images and set up compression-transmit schemes to distribute result to the remote doctor. To achieve this goal, we use basically a level-sets approach to delineating brain tumors in threedimensional. Then introduce a new compression and transmission plan of 3D brain structures based for the meshes simplification, adapted for time to the specific needs of the telemedicine and to the capacities restricted by wireless network communication. We present here the main stages of our system, and preliminary results which are very encouraging for clinical practice.
Abstract: Estimation of natural frequency of structures is very
important and isn-t usually calculated simply and sometimes
complicated. Lack of knowledge about that caused hard damage and
hazardous effects.
In this paper, with using from two different models in FEM
method and based on hydrodynamic mass of fluids, natural frequency
of an especial bearing (Fig. 1) in an electric field (or, a periodic
force) is calculated in different stiffness and different geometric. In
final, the results of two models and analytical solution are compared.
Abstract: In this paper the complete rotor system including
elastic shaft with distributed mass, allowing for the effects of oil film
in bearings. Also, flexibility of foundation is modeled. As a whole
this article is a relatively complete research in modeling and
vibration analysis of rotor considering gyroscopic effect, damping,
dependency of stiffness and damping coefficients on frequency and
solving the vibration equations including these parameters. On the
basis of finite element method and utilizing four element types
including element of shaft, disk, bearing and foundation and using
MATLAB, a computer program is written. So the responses in
several cases and considering different effects are obtained. Then the
results are compared with each other, with exact solutions and results
of other papers.
Abstract: Fertilization plays an important role in crop growth and soil improvement. This study was conducted to determine the best fertilization system for wheat production. Experiments were arranged in a complete block design with three replications in two years. Main plots consisted of six methods of fertilization including (N1): farmyard manure; (N2): compost; (N3): chemical fertilizers; (N4): farmyard manure + compost; (N5): farmyard manure + compost + chemical fertilizers and (N6): control were arranged in sub plots. The addition of compost or farm yard manure significantly increased the soil microbial biomass carbon in comparison to the chemical fertilizer. The dehydrogenase, phosphatase and urease activities in the N3 treatment were significantly lower than in the farm yard manure and compost treatments.
Abstract: In this paper, we present a robust and secure
algorithm for watermarking, the watermark is first transformed into
the frequency domain using the discrete wavelet transform (DWT).
Then the entire DWT coefficient except the LL (Band) discarded,
these coefficients are permuted and encrypted by specific mixing.
The encrypted coefficients are inserted into the most significant
spectral components of the stego-image using a chaotic system. This
technique makes our watermark non-vulnerable to the attack (like
compression, and geometric distortion) of an active intruder, or due
to noise in the transmission link.
Abstract: Construction of portable device for fast analysis of energetic materials is described in this paper. The developed analytical system consists of two main parts: a miniaturized microcolumn liquid chromatograph of unique construction and original chemiluminescence detector. This novel portable device is able to determine selectively most of nitramine- and nitroester-based explosives as well as inorganic nitrates at trace concentrations in water or soil extracts in less than 8 minutes.
Abstract: In this paper, in order to categorize ORL database face
pictures, principle Component Analysis (PCA) and Kernel Principal
Component Analysis (KPCA) methods by using Elman neural
network and Support Vector Machine (SVM) categorization methods
are used. Elman network as a recurrent neural network is proposed
for modeling storage systems and also it is used for reviewing the
effect of using PCA numbers on system categorization precision rate
and database pictures categorization time. Categorization stages are
conducted with various components numbers and the obtained results
of both Elman neural network categorization and support vector
machine are compared. In optimum manner 97.41% recognition
accuracy is obtained.
Abstract: This paper discusses the design characteristics management accounting systems should have to be useful for strategic planning and control and provides brief introductions to strategic variance analysis, profit-linked performance measurement models and balanced scorecard. It shows two multi-period, multiproduct models are specified, can be related to Porter's strategy framework and cost and revenue drivers, and can be used to support strategic planning, control and cost management.
Abstract: Amount of dissolve oxygen in a river has a great direct affect on aquatic macroinvertebrates and this would influence on the region ecosystem indirectly. In this paper it is tried to predict dissolved oxygen in rivers by employing an easy Fuzzy Logic Modeling, Wang Mendel method. This model just uses previous records to estimate upcoming values. For this purpose daily and hourly records of eight stations in Au Sable watershed in Michigan, United States are employed for 12 years and 50 days period respectively. Calculations indicate that for long period prediction it is better to increase input intervals. But for filling missed data it is advisable to decrease the interval. Increasing partitioning of input and output features influence a little on accuracy but make the model too time consuming. Increment in number of input data also act like number of partitioning. Large amount of train data does not modify accuracy essentially, so, an optimum training length should be selected.
Abstract: We proposed a technique to identify road traffic
congestion levels from velocity of mobile sensors with high accuracy
and consistent with motorists- judgments. The data collection utilized
a GPS device, a webcam, and an opinion survey. Human perceptions
were used to rate the traffic congestion levels into three levels: light,
heavy, and jam. Then the ratings and velocity were fed into a
decision tree learning model (J48). We successfully extracted vehicle
movement patterns to feed into the learning model using a sliding
windows technique. The parameters capturing the vehicle moving
patterns and the windows size were heuristically optimized. The
model achieved accuracy as high as 99.68%. By implementing the
model on the existing traffic report systems, the reports will cover
comprehensive areas. The proposed method can be applied to any
parts of the world.
Abstract: The third generation (3G) of cellular system adopted
the spread spectrum as solution for the transmission of the data in the
physical layer. Contrary to systems IS-95 or CDMAOne (systems
with spread spectrum of the preceding generation), the new standard,
called Universal Mobil Telecommunications System (UMTS), uses
long codes in the down link. The system is conceived for the vocal
communication and the transmission of the data. In particular, the
down link is very important, because of the asymmetrical request of
the data, i.e., more remote loading towards the mobiles than towards
the basic station. Moreover, the UMTS uses for the down link an
orthogonal spreading out with a variable factor of spreading out
(OVSF for Orthogonal Variable Spreading Factor). This
characteristic makes it possible to increase the flow of data of one or
more users by reducing their factor of spreading out without
changing the factor of spreading out of other users. In the current
standard of the UMTS, two techniques to increase the performances
of the down link were proposed, the diversity of sending antenna and
the codes space-time. These two techniques fight only fainding. The
receiver proposed for the mobil station is the RAKE, but one can
imagine a receiver more sophisticated, able to reduce the interference
between users and the impact of the coloured noise and interferences
to narrow band. In this context, where the users have long codes
synchronized with variable factor of spreading out and ignorance by
the mobile of the other active codes/users, the use of the sequences of
code pseudo-noises different lengths is presented in the form of one
of the most appropriate solutions.
Abstract: The structure of retinal vessels is a prominent feature,
that reveals information on the state of disease that are reflected in
the form of measurable abnormalities in thickness and colour.
Vascular structures of retina, for implementation of clinical diabetic
retinopathy decision making system is presented in this paper.
Retinal Vascular structure is with thin blood vessel, whose accuracy
is highly dependent upon the vessel segmentation. In this paper the
blood vessel thickness is automatically detected using preprocessing
techniques and vessel segmentation algorithm. First the capture
image is binarized to get the blood vessel structure clearly, then it is
skeletonised to get the overall structure of all the terminal and
branching nodes of the blood vessels. By identifying the terminal
node and the branching points automatically, the main and branching
blood vessel thickness is estimated. Results are presented and
compared with those provided by clinical classification on 50 vessels
collected from Bejan Singh Eye hospital..
Abstract: This paper describes text mining technique for automatically extracting association rules from collections of textual documents. The technique called, Extracting Association Rules from Text (EART). It depends on keyword features for discover association rules amongst keywords labeling the documents. In this work, the EART system ignores the order in which the words occur, but instead focusing on the words and their statistical distributions in documents. The main contributions of the technique are that it integrates XML technology with Information Retrieval scheme (TFIDF) (for keyword/feature selection that automatically selects the most discriminative keywords for use in association rules generation) and use Data Mining technique for association rules discovery. It consists of three phases: Text Preprocessing phase (transformation, filtration, stemming and indexing of the documents), Association Rule Mining (ARM) phase (applying our designed algorithm for Generating Association Rules based on Weighting scheme GARW) and Visualization phase (visualization of results). Experiments applied on WebPages news documents related to the outbreak of the bird flu disease. The extracted association rules contain important features and describe the informative news included in the documents collection. The performance of the EART system compared with another system that uses the Apriori algorithm throughout the execution time and evaluating extracted association rules.
Abstract: This paper presents a Particle Swarm Optimization
(PSO) method for determining the optimal parameters of a first-order
controller for TCP/AQM system. The model TCP/AQM is described
by a second-order system with time delay. First, the analytical
approach, based on the D-decomposition method and Lemma of
Kharitonov, is used to determine the stabilizing regions of a firstorder
controller. Second, the optimal parameters of the controller are
obtained by the PSO algorithm. Finally, the proposed method is
implemented in the Network Simulator NS-2 and compared with the
PI controller.
Abstract: A structural study of an aqueous electrolyte whose
experimental results are available. It is a solution of LiCl-6H2O type
at glassy state (120K) contrasted with pure water at room temperature
by means of Partial Distribution Functions (PDF) issue from neutron
scattering technique. Based on these partial functions, the Reverse
Monte Carlo method (RMC) computes radial and angular correlation
functions which allow exploring a number of structural features of
the system. The obtained curves include some artifacts. To remedy
this, we propose to introduce a screened potential as an additional
constraint. Obtained results show a good matching between
experimental and computed functions and a significant improvement
in PDFs curves with potential constraint. It suggests an efficient fit of
pair distribution functions curves.
Abstract: Clean air in subway station is important to passengers. The Platform Screen Doors (PSDs) can improve indoor air quality in the subway station; however the air quality in the subway tunnel is degraded. The subway tunnel has high CO2 concentration and indoor particulate matter (PM) value. The Indoor Air Quality (IAQ) level in subway environment degrades by increasing the frequency of the train operation and the number of the train. The ventilation systems of the subway tunnel need improvements to have better air-quality. Numerical analyses might be effective tools to analyze the performance of subway twin-track tunnel ventilation systems. An existing subway twin-track tunnel in the metropolitan Seoul subway system is chosen for the numerical simulations. The ANSYS CFX software is used for unsteady computations of the airflow inside the twin-track tunnel when the train moves. The airflow inside the tunnel is simulated when one train runs and two trains run at the same time in the tunnel. The piston-effect inside the tunnel is analyzed when all shafts function as the natural ventilation shaft. The supplied air through the shafts is mixed with the pollutant air in the tunnel. The pollutant air is exhausted by the mechanical ventilation shafts. The supplied and discharged airs are balanced when only one train runs in the twin-track tunnel. The pollutant air in the tunnel is high when two trains run simultaneously in opposite direction and all shafts functioned as the natural shaft cases when there are no electrical power supplies in the shafts. The remained pollutant air inside the tunnel enters into the station platform when the doors are opened.
Abstract: In this paper, parallelism in the solution of Ordinary
Differential Equations (ODEs) to increase the computational speed is
studied. The focus is the development of parallel algorithm of the two
point Block Backward Differentiation Formulas (PBBDF) that can
take advantage of the parallel architecture in computer technology.
Parallelism is obtained by using Message Passing Interface (MPI).
Numerical results are given to validate the efficiency of the PBBDF
implementation as compared to the sequential implementation.
Abstract: A complex valued neural network is a neural network
which consists of complex valued input and/or weights and/or thresholds
and/or activation functions. Complex-valued neural networks
have been widening the scope of applications not only in electronics
and informatics, but also in social systems. One of the most important
applications of the complex valued neural network is in signal
processing. In Neural networks, generalized mean neuron model
(GMN) is often discussed and studied. The GMN includes a new
aggregation function based on the concept of generalized mean of all
the inputs to the neuron. This paper aims to present exhaustive results
of using Generalized Mean Neuron model in a complex-valued neural
network model that uses the back-propagation algorithm (called
-Complex-BP-) for learning. Our experiments results demonstrate the
effectiveness of a Generalized Mean Neuron Model in a complex
plane for signal processing over a real valued neural network. We
have studied and stated various observations like effect of learning
rates, ranges of the initial weights randomly selected, error functions
used and number of iterations for the convergence of error required on
a Generalized Mean neural network model. Some inherent properties
of this complex back propagation algorithm are also studied and
discussed.
Abstract: Overcurrent (OC) relays are the major protection
devices in a distribution system. The operating time of the OC relays
are to be coordinated properly to avoid the mal-operation of the
backup relays. The OC relay time coordination in ring fed
distribution networks is a highly constrained optimization problem
which can be stated as a linear programming problem (LPP). The
purpose is to find an optimum relay setting to minimize the time of
operation of relays and at the same time, to keep the relays properly
coordinated to avoid the mal-operation of relays.
This paper presents two phase simplex method for optimum time
coordination of OC relays. The method is based on the simplex
algorithm which is used to find optimum solution of LPP. The
method introduces artificial variables to get an initial basic feasible
solution (IBFS). Artificial variables are removed using iterative
process of first phase which minimizes the auxiliary objective
function. The second phase minimizes the original objective function
and gives the optimum time coordination of OC relays.