Abstract: In the last years, the computers have increased their capacity of calculus and networks, for the interconnection of these machines. The networks have been improved until obtaining the actual high rates of data transferring. The programs that nowadays try to take advantage of these new technologies cannot be written using the traditional techniques of programming, since most of the algorithms were designed for being executed in an only processor,in a nonconcurrent form instead of being executed concurrently ina set of processors working and communicating through a network.This paper aims to present the ongoing development of a new system for the reconfiguration of grouping of computers, taking into account these new technologies.
Abstract: In this paper, we have compared the performance of a Turbo and Trellis coded optical code division multiple access (OCDMA) system. The comparison of the two codes has been accomplished by employing optical orthogonal codes (OOCs). The Bit Error Rate (BER) performances have been compared by varying the code weights of address codes employed by the system. We have considered the effects of optical multiple access interference (OMAI), thermal noise and avalanche photodiode (APD) detector noise. Analysis has been carried out for the system with and without double optical hard limiter (DHL). From the simulation results it is observed that a better and distinct comparison can be drawn between the performance of Trellis and Turbo coded systems, at lower code weights of optical orthogonal codes for a fixed number of users. The BER performance of the Turbo coded system is found to be better than the Trellis coded system for all code weights that have been considered for the simulation. Nevertheless, the Trellis coded OCDMA system is found to be better than the uncoded OCDMA system. Trellis coded OCDMA can be used in systems where decoding time has to be kept low, bandwidth is limited and high reliability is not a crucial factor as in local area networks. Also the system hardware is less complex in comparison to the Turbo coded system. Trellis coded OCDMA system can be used without significant modification of the existing chipsets. Turbo-coded OCDMA can however be employed in systems where high reliability is needed and bandwidth is not a limiting factor.
Abstract: The asymmetric trafc between uplink and downlink
over recent mobile communication systems has been conspicuous because
of providing new communication services. This paper proposes
an asymmetric trafc accommodation scheme adopting a multihop
cooperative transmission technique for CDMA/FDD cellular networks.
The proposed scheme employs the cooperative transmission
technique in the already proposed downlink multihop transmissions
for the accommodation of the asymmetric trafc, which utilizes
the vacant uplink band for the downlink relay transmissions. The
proposed scheme reduces the transmission power at the downlink
relay transmissions and then suppresses the interference to the uplink
communications, and thus, improves the uplink performance. The
proposed scheme is evaluated by computer simulation and the results
show that it can achieve better throughput performance.
Abstract: This paper presents dynamic voltage collapse prediction on an actual power system using support vector machines.
Dynamic voltage collapse prediction is first determined based on the PTSI calculated from information in dynamic simulation output. Simulations were carried out on a practical 87 bus test system by considering load increase as the contingency. The data collected from the time domain simulation is then used as input to the SVM in which support vector regression is used as a predictor to determine the
dynamic voltage collapse indices of the power system. To reduce training time and improve accuracy of the SVM, the Kernel function type and Kernel parameter are considered. To verify the
effectiveness of the proposed SVM method, its performance is compared with the multi layer perceptron neural network (MLPNN). Studies show that the SVM gives faster and more accurate results for dynamic voltage collapse prediction compared with the MLPNN.
Abstract: The aim of this contribution is to present a new
approach in modeling the electrical activity of the human heart. A
recurrent artificial neural network is being used in order to exhibit a
subset of the dynamics of the electrical behavior of the human heart.
The proposed model can also be used, when integrated, as a
diagnostic tool of the human heart system.
What makes this approach unique is the fact that every model is
being developed from physiological measurements of an individual.
This kind of approach is very difficult to apply successfully in many
modeling problems, because of the complexity and entropy of the
free variables describing the complex system. Differences between
the modeled variables and the variables of an individual, measured at
specific moments, can be used for diagnostic purposes. The sensor
fusion used in order to optimize the utilization of biomedical sensors
is another point that this paper focuses on. Sensor fusion has been
known for its advantages in applications such as control and
diagnostics of mechanical and chemical processes.
Abstract: The communication networks development and
advancement during two last decades has been toward a single goal
and that is gradual change from circuit-switched networks to packed
switched ones. Today a lot of networks operates are trying to
transform the public telephone networks to multipurpose packed
switch. This new achievement is generally called "next generation
networks". In fact, the next generation networks enable the operators
to transfer every kind of services (sound, data and video) on a
network. First, in this report the definition, characteristics and next
generation networks services and then ad-hoc networks role in the
next generation networks are studied.
Abstract: Various methods of geofield parameters restoration (by algebraic polynoms; filters; rational fractions; interpolation splines; geostatistical methods – kriging; search methods of nearest points – inverse distance, minimum curvature, local – polynomial interpolation; neural networks) have been analyzed and some possible mistakes arising during geofield surface modeling have been presented.
Abstract: This paper is focused on issues of nonlinear dynamic process modeling and model-based predictive control of a fed-batch sugar crystallization process applying the concept of artificial neural networks as computational tools. The control objective is to force the operation into following optimal supersaturation trajectory. It is achieved by manipulating the feed flow rate of sugar liquor/syrup, considered as the control input. A feed forward neural network (FFNN) model of the process is first built as part of the controller structure to predict the process response over a specified (prediction) horizon. The predictions are supplied to an optimization procedure to determine the values of the control action over a specified (control) horizon that minimizes a predefined performance index. The control task is rather challenging due to the strong nonlinearity of the process dynamics and variations in the crystallization kinetics. However, the simulation results demonstrated smooth behavior of the control actions and satisfactory reference tracking.
Abstract: This paper presents a mark-up approach to service creation in Next Generation Networks. The approach allows deriving added value from network functions exposed by Parlay/OSA (Open Service Access) interfaces. With OSA interfaces service logic scripts might be executed both on callrelated and call-unrelated events. To illustrate the approach XMLbased language constructions for data and method definitions, flow control, time measuring and supervision and database access are given and an example of OSA application is considered.
Abstract: The objective of this paper, is to apply support vector machine (SVM) approach for the classification of cancerous and normal regions of prostate images. Three kinds of textural features are extracted and used for the analysis: parameters of the Gauss- Markov random field (GMRF), correlation function and relative entropy. Prostate images are acquired by the system consisting of a microscope, video camera and a digitizing board. Cross-validated classification over a database of 46 images is implemented to evaluate the performance. In SVM classification, sensitivity and specificity of 96.2% and 97.0% are achieved for the 32x32 pixel block sized data, respectively, with an overall accuracy of 96.6%. Classification performance is compared with artificial neural network and k-nearest neighbor classifiers. Experimental results demonstrate that the SVM approach gives the best performance.
Abstract: The purpose of this study is to suggest energy efficient
routing for ad hoc networks which are composed of nodes with limited
energy. There are diverse problems including limitation of energy
supply of node, and the node energy management problem has been
presented. And a number of protocols have been proposed for energy
conservation and energy efficiency. In this study, the critical point of
the EA-MPDSR, that is the type of energy efficient routing using only
two paths, is improved and developed. The proposed TP-MESR uses
multi-path routing technique and traffic prediction function to increase
number of path more than 2. It also verifies its efficiency compared to
EA-MPDSR using network simulator (NS-2). Also, To give a
academic value and explain protocol systematically, research
guidelines which the Hevner(2004) suggests are applied. This
proposed TP-MESR solved the existing multi-path routing problem
related to overhead, radio interference, packet reassembly and it
confirmed its contribution to effective use of energy in ad hoc
networks.
Abstract: In this paper, we study FPGA implementation of a
novel supra-optimal receiver diversity combining technique,
generalized maximal ratio combining (GMRC), for wireless
transmission over fading channels in SIMO systems. Prior
published results using ML-detected GMRC diversity signal
driven by BPSK showed superior bit error rate performance to
the widely used MRC combining scheme in an imperfect
channel estimation (ICE) environment. Under perfect channel
estimation conditions, the performance of GMRC and MRC
were identical. The main drawback of the GMRC study was
that it was theoretical, thus successful FPGA implementation
of it using pipeline techniques is needed as a wireless
communication test-bed for practical real-life situations.
Simulation results showed that the hardware implementation
was efficient both in terms of speed and area. Since diversity
combining is especially effective in small femto- and picocells,
internet-associated wireless peripheral systems are to
benefit most from GMRC. As a result, many spinoff
applications can be made to the hardware of IP-based 4th
generation networks.
Abstract: An Ad hoc wireless network comprises of mobile
terminals linked and communicating with each other sans the aid of
traditional infrastructure. Optimized Link State Protocol (OLSR) is a
proactive routing protocol, in which routes are discovered/updated
continuously so that they are available when needed. Hello messages
generated by a node seeks information about its neighbor and if the
latter fails to respond to a specified number of hello messages
regulated by neighborhood hold time, the node is forced to assume
that the neighbor is not in range. This paper proposes to evaluate
OLSR routing protocol in a random mobility network having various
neighborhood hold time intervals. The throughput and delivery ratio
are also evaluated to learn about its efficiency for multimedia loads.
Abstract: Restructured electricity markets may provide
opportunities for producers to exercise market power maintaining
prices in excess of competitive levels. In this paper an oligopolistic
market is presented that all Generation Companies (GenCos) bid in a
Cournot model. Genetic algorithm (GA) is applied to obtain
generation scheduling of each GenCo as well as hourly market
clearing prices (MCP). In order to consider network constraints a
multiperiod framework is presented to simulate market clearing
mechanism in which the behaviors of market participants are
modelled through piecewise block curves. A mixed integer linear
programming (MILP) is employed to solve the problem. Impacts of
market clearing process on participants- characteristic and final
market prices are presented. Consequently, a novel multi-objective
model is addressed for security constrained optimal bidding strategy
of GenCos. The capability of price-maker GenCos to alter MCP is
evaluated through introducing an effective-supply curve. In addition,
the impact of exercising market power on the variation of market
characteristics as well as GenCos scheduling is studied.
Abstract: In this paper a PID control strategy using neural
network adaptive RASP1 wavelet for WECS-s control is proposed.
It is based on single layer feedforward neural networks with hidden
nodes of adaptive RASP1 wavelet functions controller and an infinite
impulse response (IIR) recurrent structure. The IIR is combined by
cascading to the network to provide double local structure resulting
in improving speed of learning. This particular neuro PID controller
assumes a certain model structure to approximately identify the
system dynamics of the unknown plant (WECS-s) and generate the
control signal. The results are applied to a typical turbine/generator
pair, showing the feasibility of the proposed solution.
Abstract: Routing in MANET is extremely challenging because
of MANETs dynamic features, its limited bandwidth, frequent
topology changes caused by node mobility and power energy
consumption. In order to efficiently transmit data to destinations, the
applicable routing algorithms must be implemented in mobile ad-hoc
networks. Thus we can increase the efficiency of the routing by
satisfying the Quality of Service (QoS) parameters by developing
routing algorithms for MANETs. The algorithms that are inspired by
the principles of natural biological evolution and distributed
collective behavior of social colonies have shown excellence in
dealing with complex optimization problems and are becoming more
popular. This paper presents a survey on few meta-heuristic
algorithms and naturally-inspired algorithms.
Abstract: This paper describes an experience of research,
development and innovation applied in Industrial Naval at (Science
and Technology Corporation for the Development of Shipbuilding
Industry, Naval in Colombia (COTECMAR) particularly through
processes of research, innovation and technological development,
based on theoretical models related to organizational knowledge
management, technology management and management of human
talent and integration of technology platforms. It seeks ways to
facilitate the initial establishment of environments rich in
information, knowledge and content-supported collaborative
strategies on dynamic processes missionary, seeking further
development in the context of research, development and innovation
of the Naval Engineering in Colombia, making it a distinct basis for
the generation of knowledge assets from COTECMAR.
The integration of information and communication technologies,
supported on emerging technologies (mobile technologies, wireless,
digital content via PDA, and content delivery services on the Web 2.0
and Web 3.0) as a view of the strategic thrusts in any organization
facilitates the redefinition of processes for managing information and
knowledge, enabling the redesign of workflows, the adaptation of
new forms of organization - preferably in networking and support the
creation of symbolic-inside-knowledge promotes the development of
new skills, knowledge and attitudes of the knowledge worker
Abstract: Next Generation Wireless Network (NGWN) is
expected to be a heterogeneous network which integrates all different
Radio Access Technologies (RATs) through a common platform. A
major challenge is how to allocate users to the most suitable RAT for
them. An optimized solution can lead to maximize the efficient use
of radio resources, achieve better performance for service providers
and provide Quality of Service (QoS) with low costs to users.
Currently, Radio Resource Management (RRM) is implemented
efficiently for the RAT that it was developed. However, it is not
suitable for a heterogeneous network. Common RRM (CRRM) was
proposed to manage radio resource utilization in the heterogeneous
network. This paper presents a user level Markov model for a three
co-located RAT networks. The load-balancing based and service
based CRRM algorithms have been studied using the presented
Markov model. A comparison for the performance of load-balancing
based and service based CRRM algorithms is studied in terms of
traffic distribution, new call blocking probability, vertical handover
(VHO) call dropping probability and throughput.
Abstract: To define or predict incipient motion in an alluvial
channel, most of the investigators use a standard or modified form of
Shields- diagram. Shields- diagram does give a process to determine
the incipient motion parameters but an iterative one. To design
properly (without iteration), one should have another equation for
resistance. Absence of a universal resistance equation also magnifies
the difficulties in defining the model. Neural network technique,
which is particularly useful in modeling a complex processes, is
presented as a tool complimentary to modeling incipient motion.
Present work develops a neural network model employing the RBF
network to predict the average velocity u and water depth y based on
the experimental data on incipient condition. Based on the model,
design curves have been presented for the field application.
Abstract: The lack of any centralized infrastructure in mobile ad
hoc networks (MANET) is one of the greatest security concerns in
the deployment of wireless networks. Thus communication in
MANET functions properly only if the participating nodes cooperate
in routing without any malicious intention. However, some of the
nodes may be malicious in their behavior, by indulging in flooding
attacks on their neighbors. Some others may act malicious by
launching active security attacks like denial of service. This paper
addresses few related works done on trust evaluation and
establishment in ad hoc networks. Related works on flooding attack
prevention are reviewed. A new trust approach based on the extent of
friendship between the nodes is proposed which makes the nodes to
co-operate and prevent flooding attacks in an ad hoc environment.
The performance of the trust algorithm is tested in an ad hoc network
implementing the Ad hoc On-demand Distance Vector (AODV)
protocol.