|
The following papers were presented in the
2002 WSEAS Int. Conf. on System Science, Applied Mathematics & Computer Science, and Power Engineering Systems.
(Data Base in MicroSoft Access 2002).
|
| 103 R-conversion method as a new generation of cryptography systems |
pp. 1031-1037 |
|
|
by : Theodore Datri, Telman Askerov, Serguei Lebedev, Arif Askerov
Abstract: - The R-Conversion Encryption Method the universal cryptography algorithm of the binary initial sequence. This method is based on the conception of self-defined data.The power of this algorithm does not depend on any mathematics knowledge and develops just from the number of operations you need to make to crack this algorithm. |
| 111 Intelligent neural systems for safety control |
pp. 1111-1115 |
|
|
by : Robert A. Kosinski
Abstract: - Abstract: - Safety system for recognition of danger situations at automatized work stands (e.g. with stationary robots) is presented. The system consists of a vision part based on the TV camera connected with a frame grabber which observes the neighbourhood of the robot and a set of cellular neural networks which analyses the sequence of images transmitting from the camera. The neural system is able to work in a real time and react intelligently on the objects appearing near the robot. If the situation is danger the system stops the robot, thus preventing the collision. |
| 112 Generalized algorithms of discrete optimization and their applications |
pp. 1121-1126 |
|
|
by : Petr Ekel, Reinaldo Palhares, Whester Araujo, Marina Silva, Vladimir Popov, Anatolij Bondarenko, Vadim Tkachenko
Abstract: - Generalized algorithms for solving problems of discrete, integer, and Boolean programming are discussed. These algorithms are associated with the method of normalized functions, are based on a combination of formal and heuristic procedures, and allow one to obtain quasioptimal solutions after a small number of steps, that promotes overcoming the NP-completeness of discrete optimization problems. Questions of building so-called "duplicate" algorithms are considered to improve the quality of discrete optimization problem solutions. The subsequent development of the algorithms is related to using their modifications to solve optimization problems under conditions of uncertainty within the framework of a general approach to analyzing models with fuzzy coefficients in objective functions and constraints. In practical aspect, the algorithms are already being used to solve diverse problems of power engineering. |
| 116 Controllability of nonlinear systems |
pp. 1161-1164 |
|
|
by : J.Klamka
Abstract: - In the paper, infinite-dimensional, continuous-time control systems described by nonlinear abstract differential equations are considered. Using methods of functional analysis sufficient conditions for constrained exact local controllability are formulated and proved. It is generally assumed that the values of controls are in a convex and closed cone with vertex at zero. Illustrative examples are also given. Moreover, some remarks and comments on controllability problems for nonlinear dynamical systems are presented. |
| 117 Constrained controllability of distributed parameter system |
pp. 1171-1174 |
|
|
by : J.Klamka
Abstract: - In the paper constrained controllability of distributed parameter dynamical system defined in infinite-dimensional domain is considered. Using spectral theory of unbounded differential operators, necessary and sufficient conditions constrained controllability are formulated and proved. Remarks and comments on the relationships between different kinds of controllability are also given. Simple numerical examples of controllable systems are presented. |
| 120 A simple regulators optimization method for a thyristorized controlled induction motor drive system |
pp. 1201-1206 |
|
|
by : Rezek, A. J. J.;Pereira, C. A. G.;Silva, V. F.;Cortez, J. A.;Vicente, J. M.E.
Abstract: - Abstract - The capacitor excited induction motor is fed by a natural commutated inverter. The control system has been implemented to modify the rectifier voltage. The inverter firing technique used has been the machine terminal voltage sensor, employing the dedicated integrated circuit TCA 780 (Icotron-Siemens). The reference pins (5) of the TCAÔs 780 are supplied by the secondary voltages of two synchronizing transformers, connected to the electrical system and the machine terminals for the rectifier and inverter firing units, respectively. The pulses are generated by TCAÔs 780 using the ramp method. The control system has been implemented to modify the rectifier voltage. For this purpose there are the speed and current regulators designed according to the symmetric optimization criterion. These regulators have been determined using a simple design procedure that will be presented in this paper. A DC control level voltage VCC (0-10[V]) connected to the pins 11 of the TCAÔs 780 makes possible the modification of the firing angle (alfa), in a way that for a VCC of 10[V] there is an alfa of 180 degrees, and for a VCC of 0[V], alfa equals 0 degrees. An intermediary value of alfa can be obtained by modifying VCC, so that the relationship between alfa and VCC remains linear. The DC control voltage of the rectifier (VCCR)) is varying, but the control voltage of the inverter (VCCI) remains always 0[V]. In this case a zero crossing machine terminal voltage has been used to fire the inverter. The synchronizing transformer used in this case has been a special transformer delta/zig-zag 195 degrees, so the inverter firing angle is constant and equals 165 degrees. The rectifier synchronizing transformer is delta zig-zag z-30 degrees and the firing angle of this unit is varying. The inner proportional integral (PI) regulator makes possible the limitation of the motor current and both PI speed and current regulators act when a load disturbance torque occurs or in a drop in the rectifier voltage. The motor current and speed signals, have been registered in these cases, by using a storage oscilloscope, and the experimental results discussed. Presently digital PI and fuzzy regulators are being implemented to compare the results of the dynamic behavior of the controlled system. |
| 127 Adjustment Methods and Without Replacement Bootstrap: Applications to a Business Survey |
pp. 1271-1275 |
|
|
by : A.C.M.Costa
Abstract: - Applications of several adjustment methods and the Without Replacement Bootstrap (BWO) are presented, using data from the 1997 Annual Business Survey, conducted by PortugalÔs National Statistics Institute. The application of these methods is motivated by issues related with frame problems and total nonresponse. The BWO algorithm is used for variance estimation of the considered estimators: the adjustment cell estimator, the post-stratified estimator and the post-stratified estimator with adjustment cells. The results agree with the theoretical evidences referred in the literature. |
| 128 Fuzzy web-based information retrieval systems |
pp. 1281-1284 |
|
|
by : Dulce MagalhÞes de SÜ
Abstract: - The main problem on the Web is to locate information. Some reasons for this arise from the inefficiency of interfaces, incorrect information organization and data structure issues. A fuzzy approach to information retrieval systems can mitigate these problems. Advantages of fuzzy logic over sharp ones are the retrieval of information items which partial match the query and their ranking of importance, because in fuzzy logic an information element can reside in more than one set of different degrees of similarity. This provides a tool for natural language interfaces in retrieval systems and a solution for some Web-based information retrieval problems. |
| 129 On the essential spectrum of the operators generated by PDE systems of stratified fluids |
pp. 1291-1295 |
|
|
by : Andrei Giniatoulline
Abstract: - We establish the localization and the structure of the spectrum of normal vibrations described by systems of partial differential equations modelling small displacements of stratified fluid in the homogeneous gravity field. We also compare the spectral properties of gravitational and rotational operators. The similarity of the essential spectrum for stratified and rotational flows corresponds to the analogy in the propagation of gravitational and Coriolis waves in viscous fluids, whose consideration includes the study of qualitative properties of the solutions, such as existence, uniqueness, smoothness, asymptotics, etc. |
| 135 Testing with Model Checker: Insuring Fault Visibility |
pp. 1351-1356 |
|
|
by : Vadim Okun, Paul E. Black, Yaacov Yesha
Abstract: - To detect a fault in software, a test case execution must enable an intermediate error to propagate to the output. We describe two specification-based mutation testing methods that use a model checker to guarantee propagation of faults to the visible outp |
| 136 A Hydrothermal Optimal Power Flow Problem Solved by Lagrangian Relaxation Approach |
pp. 1361-1366 |
|
|
by : Leonardo Nepomuceno, Secundino Soares, Takaaki Ohishi
Abstract: - Short-term Generation Scheduling models (STGS) are concerned with the calculation of an optimal generation policy while taking into account various operational limits in transmission and generation systems. Most STGS models described in the literature totally ignore representation of reactive portions of the transmission system. Such purely active models tend to calculate generation policies that may lead the system to operating points presenting security problems associated with reactive aspects (such as voltage instability, etc.). A class of problems denominated Hydrothermal Optimal Power Flow (HOPF) models have been proposed to represent active/reactive STGS studies. This paper proposes a HOPF model concerned with detailed representation of active and reactive aspects of the transmission system. Lagrangian Relaxation is applied to solve the proposed HOPF model. This technique is based on relaxation of dynamic constraints together with the coordination of such constraints using Lagrange multipliers. HOPF and the proposed solution technique are applied to IEEE 30 bus test system. Solutions obtained by the HOPF model are compared with those obtained by purely active dispatch models. Results point-out the importance of the representation of reactive aspects in dispatch studies. Results also confirm robustness of the proposed solution methodology. |
| 137 Application of the wavelets in 2D scattering problems |
pp. 1371-1373 |
|
|
by : A.Anuytin,V.Stasevich
Abstract: - - Wavelets technique is applied for solving of 2D Dirichlet, Neumann and mix boundary problems. The developed method utilizes Haar or linear B-spline functions and Fredholm integral equations (-or a system of the Fredholm integral equations) of fist kind with smooth or singular kernels. The problems of accuracy, choosing auxiliary surfaces end stable results are discussed. |
| 139 Parallel Genetic Algorithms Applied to Damping Controllers Tuning on a Linux Cluster of PCs |
pp. 1391-1396 |
|
|
by : Carmen L. T. Borges, Enrique C. Viveros, Glauco N. Taranto
Abstract: - The coordinated tuning of power system stabilizers (PSS) consists of an optimization problem where the objective function is to maximize system damping. Since conventional optimization methods tend to obtain a local optimum instead of a global one, the application of Genetic Algorithms (GA) to this problem has been considered. However, the computational effort required by the GA approach is very high and may become prohibitive for large-scale systems. This paper presents the implementation of two categories of Parallel Genetic Algorithms (PGA) applied to the PSS tuning problem, namely: master-slave and multi-population. In the master-slave PGA, the evaluation of the many chromosomes within a sole population is performed in parallel, whereas in the multi-population PGA, many populations are evaluated concurrently on different processors. Different communication topologies, migration rates and substitution strategies have been exploited in the multi-population PGA in order to evaluate the parallel speedup. The parallel platform utilized is a Linux cluster of PCs composed of 24 microcomputers interconnected by a switched Fast-Ethernet network. The results obtained show high speedup and good parallel efficiency on actual power system models. |
| 140 Particle Swarm Optimization versus Genetic Algorithms for Fitting Fuzzy Membership Functions |
pp. 1401-1406 |
|
|
by : Ahmed Ali Abdalla Esmin, Alexandre Rasi Aoki, and Germano Lambert-Torres
Abstract: - The use of Fuzzy Control has been increasing considerably, and its success depends on a number of parameters, such as fuzzy membership functions, that are usually decided upon subjectively. The objective of this paper is to describe and discuss how to improve the performance of the fuzzy reasoning model through fitting fuzzy membership functions using Particle Swarm Optimization algorithm and Genetic Algorithms. An application designed to park a vehicle into a garage; beginning from any start position is used as a case study. Finally the obtained results are discussed and the performance is compared. |
| 142 Multilevel Adaptive Prefilter for MW Contingency Selection |
pp. 1421-1426 |
|
|
by : Antonio F. Guerra, Carlos A. Castro
Abstract: - This paper focuses on the MW contingency selection problem. It is assumed a real time operation environment. A multilevel prefilter is proposed, so as to discard the contingencies that are certainly harmless to the system operation from the standpoint of MW power overflows. The prefilter is also adaptive, since information from one operation cycle can be used in the next operation cycle, provided that the change in the system operating conditions is small, which is often the case. Simulation results show that the proposed prefilter is accurate and results in significant computational time savings. |
| 143 An Investigation of TCSC and Load Dynamics Influence on Power System Inter-Area Mode Oscillations |
pp. 1431-1436 |
|
|
by : Adriana F. Domingues, Vivaldo F. da Costa, Luiz C. P. da Silva
Abstract: - Thyristor Controlled Series Capacitor (TCSC) is a prominent FACTS (Flexible AC Transmission Systems) device that can rapidly modulate the reactance of a transmission line, resulting in improvement of system performance. In this paper, simulations studies of a simple two-area power system model were conducted to investigate the damping effects of the TCSC and load dynamics on inter-area mode oscillations. The study is based on investigation of the eigenvalues of the linearized power system model in the framework of dynamic bifurcation theory. |
| 144 Experimental Setup for Autonomous Induction Generator System with Voltage and Frequency Regulation Studies |
pp. 1441-1446 |
|
|
by : Pereira, V. M., Pomilio, J. A. and Ferreira, P. A.V.
Abstract: - A Diesel engine is commonly used to drive a generator for autonomous production of electricity. An induction generator associated with a PWM inverter can substitute the synchronous generator. The inverter allows stabilizing voltage and frequency, while the power flow is controlled adjusting the speed. This paper presents an investigation of a self-excited induction generator system with adjustable speed. The system uses a PWM inverter connected at the generator output and it is able to maintain constant three-phase voltage and frequency, eliminating the drawbacks of the induction generator isolated systems. For experimental purposes, a DC motor emulates the dynamic behavior of the Diesel motor. Considering the models and open-loop transfer functions of both motors, reduced-order dynamic representations and the necessary filters to match the models are obtained. Simulated and experimental results confirm that the system presents satisfactory behavior at steady state and under load transients. The experimental setup based on a DC motor can be used for laboratorial studies of the system. |
| 146 48-Pulse Based SSSC (Static Synchronous Series Compensator), an Evaluation of its Performance |
pp. 1461-1466 |
|
|
by : Ricardo Arnez, Luiz Zanetta
Abstract: - This paper presents a performance comparison between a 24-pulse and a 48-pulse phase-shift VSI based SSSC. Initially a brief but useful description of the SSSC basic operation, is presented. Simulations of the two configurations have been carried out using the EMTP program. It has been found that the 48-pulse based SSSC, may well avoid the presence of harmonic filters, because it presents a nearly sinusoidal set of three-phase voltage waveforms which clearly agree with power quality standards. It is also shown the SSSC ability in modifying instantaneously both active and reactive power. Within the current electric market, a continuous assessment of the technical performance of this device and the other FACTS members, is needed. |
| 148 Finite dynamical systems, linear automata, and finite fields |
pp. 1481-1483 |
|
|
by : O. Moreno, D. Bollman, M.A. Andino
Abstract: - We establish a connection between finite fiels and finite dynamical systems. We show how this connection can be used to shed light on some problems in finite dynamical systems and in particular, in linear systems. |
| 150 Proposal of a Framework for Workflow Processs Automation Systems based on .NET Framework and XML Web Services |
pp. 1501-1508 |
|
|
by : Rogerio Nascimento, Arnaldo Martins, Joaquim Pinto, Eduardo Carrillo
Abstract: - Our main goal is the interrelation amongst the new metadata paradigm - the XML family - and the Workflow Process Automation, and its integration and interaction with database legacy systems. We intend to answer two fundamental subjects: the granularity of XML documents that support the framework, and the cross-reference capacity with other files or databases in a system, being both supported by XML databases. We used TEXTML Server as a back end system for intermediating and recovering information from binary and XML files. In out case study, we implemented a multimedia and heterogeneous distributed system based on Web Services, SOAP and WSDL. The main idea in the proposal of the framework was separate the problem and the solution. For that, we used workflow process management techniques and Web Services. We also built XML Schemas to generated XML files, indexes for TEXTML Server and XSL files to format data for each system front-end like PDAÔs, third generation mobile phones (GPRS, UMTS) and personal computers. We based on WFMC reference model we are testing a workflow process automation prototype to be used in the information management system of legislative data of the portuguese parliament. All this was embedded in the new MicrosoftÔs platform for software components: the .NET Framework. |
| 156 Domain Estimation Techniques Applied to an Agricultural Survey |
pp. 1561-1565 |
|
|
by : Maria Helena Guerra
Abstract: - Several methods of domain estimation are analysed and tested according to the specific problem of an agricultural survey conducted by the Portuguese National Statistics Institute. The importance of use of appropriate auxiliary information in the scope of the domain estimation is emphasized. It is shown that, the choice of auxiliary variables that are correlated with the variables of interest and its use through several techniques of domain estimation, allows getting considerable gains of accuracy. The bootstrap algorithm and the Taylor linearization are used for variance estimation. The precision of the analyzed estimators is discussed and some recommendations are made regarding their applications under this survey. |
| 157 Impact of Stator Pole Shape of Synchronous Motor on Torque |
pp. 1571-1574 |
|
|
by : Anton Hamler, Mladen Trlep, Bojan Ëtumberger, Marko Jesenik
Abstract: - The paper presents pole modelling of small one phase 10 poles synchronous motor with permanent magnets. The purpose of stator pole modelling is to provide a reliable operation of the motor with in advance prescribed direction of rotation with 80 % of the rated voltage. For analysis of magnetic conditions the 2D finite element method was used. Intuitive and trial modelling procedures were used for pole modelling. |
| 158 Solution of Simultaneous Non-Linear Equations using Genetic Algorithms |
pp. 1581-1588 |
|
|
by : Angel Fernando Kuri-Morales
Abstract: - . The solution of Systems of Simultaneous Non-Linear Equations (SNLE) remains a complex and as yet not closed problem. Although analytical methods to tackle such problems do exist, they are limited in scope and, in general, demand certain prior knowledge of the functions under study. In this paper we propose a novel method to numerically solve such systems by using a Genetic Algorithm (GA). In order to show the generality of the method we first prove a theorem which allows us to equate the SNLE problem to that of minimizing a linear combination of the equations to be solved, subject to a set of constraints. Then we describe a rugged GA (the so-called Vasconcelos GA or VGA) which has been proved to perform optimally in a controlled but unbounded problem space. Next, we show how the VGA may be efficiently utilized to adapt its behavior (which is inherently adequate to solve unconstrained minimization problems) to a constrained solution space. Finally, we offer some examples of systems of non-linear equations which were solved using the proposed methodology. |
| 167 Regularization Algotithms for Electric Tomography Images Reconstruction |
pp. 1671-1676 |
|
|
by : Alexandre Grebennikov
Abstract: - Abstract: - Electrical Tomography consists in reconstruction the image of the body interior on the measuraments made on the it's surface. Mathematically it can be described as a coefficient inverse problem for the Laplace equation, written in the divergent form. The coefficient is the functions of the space variables and characterize the electrical properties of a media. Well know and the most developed now approach is Electrical Impedance Tomography, that includes the resistence and capacitance tomographies. It use the measuraments of the voltages on the surface produced under the the known injected currents. This method has some advantiges, but it's algorithmic realization is sufficiently hard, because of nonlinear structure of the mathematical model. We propose here another approach for the plane case, based on the original use of the Radon transformation. We use regularization by spline-approximation method for the explicit realization of the inverse Radon transformation, that leads to the fast algorithm of the image reconstruction. These approach and algotithms are justified with the numerical experiments on the simulated model problems. |
| 172 An HMM based phonetic vocoder using mixed exitation |
pp. 1721-1724 |
|
|
by : Ranniery Maia, Ricardo Cirigliano, Daniel Rojtenberg, Fernando Resende
Abstract: - This work describes a phonetic vocoder at an average bit rate of 1.3 kbps using HMM-based speech recognition/synthesis techniques.Mixed excitation is applied during the synthesis procedure in order to solve the problem of having unnatural synthetic speech when the traditional binary excitation pulse train/random noise is applied. The new excitation efficiently produces more natural speech while reducing the bit rate when compared to the traditional excitation. |
| 173 robust h-infinity fuzzy filtering for a class of state-delayed nonlinear systems in an lmi setting |
pp. 1731-1736 |
|
|
by : Reinaldo Palhares, Michel Hell, Lauro Duraes, Joao Ribeiro Neto, Petr Ekel, Marcelo Teixeira, Edvaldo Assuncao
Abstract: - The problem of H-infinity filtering design for a class of nonlinear systems with time-delay via Takagi-Sugeno fuzzy models is investigated in this paper. Sufficient conditions for the existence of a stable nonlinear filter assuring global asymptotic stability and a prescribed H-infinity noise attenuation level to the filtering error are established in terms of linear matrix inequalities. Moreover, it is shown how to consider the proposed approach to deal with uncertain parameters or systems without delay. Finally, a discrete-time nonlinear system with time-delay is investigated as a numerical example. |
| 179 A Visual Tool to Distribution Network Reconfiguration |
pp. 1791-1795 |
|
|
by : Marcelo E. de Oliveira, Luis F. Ochoa, Antonio Padilha, Jose Roberto S. Mantovani
Abstract: - Power distribution network reconfiguration is performed with open/close operations of sectionalizing switches, maintaining the feeder's radial topology, aimed to losses minimization and load balancing. A distribution networks simulator with a friendly graphic interface and reconfiguration functions, developed in Visual Basic language, is presented. The simulator shows quick response, based on load flow and losses calculation, with the best configurations for each load situation, obtained by an algorithm previously developed using Fortran language. This approach is a great tool for training, education, but it is also useful for distribution networks planning and operation. The user can easily see the network configuration with different values of voltage drop and power losses for each situation |
| 180 Compression criteria for voltage sags analysis using wavelets |
pp. 1801-1806 |
|
|
by : Gustavo Castro,Sigmar Deckmann, Andre Ferreira
Abstract: - The use of wavelet decomposition to provide data recording and analysis of Power Quality disturbances depends on establishing an acceptable compromise between high data compression and low energy loss capability, in order to preserve the basic waveform features during signal reconstruction. This paper compares three threshold rules to evaluate compression efficiency, using the retained energy indicator as a signal reconstruction quality index. |
| 181 Design and Construction of 150 kV/300 A/ 1us Blumlein Pulser |
pp. 1811-1815 |
|
|
by : Rossi JO, Ueda M, Barroso JJ
Abstract: - Blumlein pulsers are well suited devices for high voltage pulse generation in the range of nanoseconds or microseconds. They consist of pieces of transmission lines charged in parallel and discharged synchronously in series into the load by using a single switch. The main problems with this type of circuit are the presence of the shield cable impedance that contributes to the power loss of the device and the requirement of long lengths of lines for operation in the microsecond range. In view of that, this paper presents a construction method that minimizes these losses and reduces the generator size by using coaxial lines coiled up on cylindrical tubes. In particular, we report the construction of a 150kV/300A/1us Blumlein pulser that has been carried out in our laboratory, including a PSPICE simulation of the output pulse voltage of the generator. |
| 183 A hybrid artificial life system for optimization of functions |
pp. 1831-1836 |
|
|
by : Chen Yang,Hong Yu Su, Hao Ye
Abstract: - In this paper, a hybrid Artificial Life (ALife) system for function optimization that combines ALife colonization with Genetic Algorithm (GA) is proposed. The method includes two stages. In the first stage, the emergent colonization of ALife system is used to provide an excellent initial population for GA, and GA is further used to find the optimal solution in the second stage. The hybrid method is compared with ordinary ALife based optimization approach and ordinary GA approach respectively by simulation. |
| 191 Liberalization of Croatian Electricity Market and Restructuring of Croatian Power Utility |
pp. 1911-1917 |
|
|
by : Slavko Krajcar, Ante Curkovic, Davor Skrlec
Abstract: - Depending on the obligation to open its electricity and gas markets to competition, in line with EU-wide minimum levels, most of the transitional countries of central and eastern Europe including Croatia are in the throes of electricity privatization and deregulation. Economic stability, EU-compatible legislation and competition laws are prerequisite conditions in establishing deregulated electricity market. The deregulation process requests prior restructuring of the state-owned electric utility with a view to carry out successful privatization process and utility make competent for the competition on the liberalized market. High diversity of restructuring process of the state-owned electric utilities, both at the regulatory regime and firm level, causes a multiplicity of strategic configuration and strategic developments. This paper presents the basic concept of the evolution of the Croatian State Power Utility (HEP) from a classic monopolistic state-owned electric utility to a modern corporation. |
| 195 An Intelligent Distributed System Applied on Automated Lift System |
pp. 1951-1955 |
|
|
by : Jes Cerqueira, Arnaldo de Jesus, Eduardo Dantas, Carlos Pereira, Gabriel Albuquerque, Madalena Frisch, Herman Lepkison, Antonio Bitencourt, Fernando Pereira, Jose Correa
Abstract: - This paper introduces the application of Symbolic Neural Network in an intelligent distributed system for automated petroleum lift systems. It also introduces the application of a special kind of perceptron for the pattern recognition of graphic cards applied on the lift system analysis. Applications on rod-pumb wells are illustraded |
| 196 The Influence of Generator Voltage Control Modeling on Transmission Network Loading Assessment |
pp. 1961-1966 |
|
|
by : R.B. Prada, B.T. Seelig, J.O.R. dos Santos, L.S. Pilotto, A. Bianco
Abstract: - Generator voltage control may be modeled assuming the terminal bus as a PV bus or a variable voltage source behind the synchronous reactance connected to the voltage controlled terminal bus. Voltage control is lost when generator reactive power is exhausted. Generator terminal bus should be a PQ bus or a fixed voltage behind the synchronous reactance connected to the terminal bus. This paper shows that maximum transmission of active and reactive power to the load is the same, provided the terminal voltage is kept controlled. However, if voltage control is not maintained in the terminal bus, different models lead to different maximum loads that can be supplied by the network. |
| 199 A multi-blackboard approach to the control/monitoring of APS |
pp. 1991-1996 |
|
|
by : Insaf Tnazefti, Luciana Arantes and Olivier Marin
Abstract: - This paper presents a multi-blackboard approach to design and implement a control/monitoring system for the Automation of Production Systems. The proposed architecture is composed of several control/monitoring agents (CMAs) organised hierarchically. Communication between agents is done through a corresponding hierarchy of blackboards, in which the consistency of replicated data is maintained. |
| 203 a four-quadrant analog multiplier biased at 1.2v working in current-mode |
pp. 2031-2034 |
|
|
by : Alejandro Diaz-M., Juan Carlos Sanchez-G., Miguel Garcia-A., Esteban Tlelo-C.
Abstract: - Analog multipliers are widely used in fuzzy logic, analog signal, and parallel processing systems. The most important is that, since low-voltage applications have become popular, several efforts have been oriented to improve the performance of the proposed designs. In that way, a design of a current-mode four-quadrant analog multiplier, based on the translinear principle, and biased at 1.2V, is presented. Simulation results using HSPICE show an improvement on the linearity. The proposed circuit was designed using CMOS technology of 0.8mm process parameters from AMS. |
| 204 Solving the Welch-Berlekamp key equation over a Galois ring |
pp. 2041-2045 |
|
|
by : Marc A. Armand
Abstract: - The Welch-Berlekamp (WB) key equation arises in the decoding of Reed-Solomon (RS) codes over finite fields where the decoding problem is viewed as a rational interpolation problem. The significance of this decoding approach lies in the fact that it does not require the prior evaluation of power sum symmetric functions, i.e. the so-called syndrome vector corresponding to a received word. It has recently been shown that RS codes over Z_q, q a prime power, can also be decoded in the same way as their field counterparts. The purpose of this paper is therefore to present a generalization of a WB-type algorithm for solving the key equation over a Galois ring. |
| 207 A neural network applied to map and to compute overvoltages related to lightning in power systems |
pp. 2071-2075 |
|
|
by : Andre Nunes de Souza, Fernando Carneiro L. Amaral,Ivan Nunes da Silva,Maria Goretti Zago
Abstract: - This paper describes a novel approach for mapping overvoltages related to lightning in power system using artificial neural networks. The network acts as identifier of structural features of the grounding processes. So that output parameters can be estimated and generalized from an input parameter set. Simulation examples are presented to validate the proposed approach. More specifically, the neural networks are used to compute the overvoltages of grounding system taking into account time, waveform, soil resistivity and impulse current. The results obtained by the network are compared with other approaches also used to model grounding systems related to lightning. |
| 208 A derivation of interactor for non-square plants and pseudo inverted interactorizing by state feedback |
pp. 2081-2087 |
|
|
by : Wataru Kase, Takuya Watanabe
Abstract: - An interactor matrix plays some important roles in control system analysis and synthesis. Recently, a simple derivation of the interactor matrix using pseudoinverse. Unfortunately, this method is limited to square systems. In this paper, it will be presented a simple derivation of an interactor matrix for non-square transfer function matrices. A pseudo inverted interactorizing will be proposed and achieved by using state feedback. |
| 213 Statistical and Neural Network Modeling and predictions of Tides in the Shallow Waters of the Gulf of Mexico |
pp. 2131-2136 |
|
|
by : Alexey L. Sadovski, Phillippe Tissot, Patrick Michaud, Carl Steidley
Abstract: - Abstract: - This paper presents a preliminary report of statistical modeling for filling gaps in the data collected to make predictions of tides in the shallow waters of the Gulf of Mexico. The approach discussed is based on data gathered by the Texas Coastal Ocean Observation Network (TCOON). By applying multiple regression and factor analysis to different kinds of data (water level, wind speed and direction, water temperature) we were able to make quite reliable predictions from 6 to 72 hours. Results of this investigation were compared with predictions based on the usage of Neural Networks, and integration of these two approaches looks very promising. |
| 214 Defensive Programming for Safety-Critical Systems |
pp. 2141-2146 |
|
|
by : Jorge R. de Almeida Jr., Selma S. S. Melnikoff, Joao B. de Camargo Jr., Benicio Jose de Souza
Abstract: - This paper presents some techniques of defensive programming to be used in software based safety-critical systems. The use of defensive programming in such systems is important and it is totally justified because some problems can cause serious consequences. The use of defensive programming can reduce the risk level of safety-critical systems, contributing to produce high quality software demanded by international standards. Main problems found in software of safety-critical systems are also presented, with the correspondent way of treatment, based in the described techniques |
| 216 Calculation of Operational Parameters in Primary Distribution Networks using Artificial Neural Networks |
pp. 2161-2166 |
|
|
by : Ana Garcia Hernan Prieto
Abstract: - Abstract: A new methodology for estimation of performance parameters in electricity distribution systems is presented in this paper. These parameters include maximum voltage drop, maximum power losses and length of feeders. The methodology, which can used in both planning and operational studies, is based on the MLP - Multi Layer Perceptron paradigm of Artificial Neural Networks. A second methodology was developed so as to improve MLP performance in the parameter estimation process, as well as to improve the statistical expressions used in the training and validation of the MLP model. This methodology is based on probabilistic simulation and represents an alternative way of generating scenarios for the establishment of statistical expressions. The differences arising between the conventional scenario generation (through enumeration of parameter combinations) and the probabilistic simulation motivated the inclusion of a detailed analysis of the statistical expressions themselves. |
| 220 an adaptative neuro-fuzzy inference system based on dissolved gas analysis for faults diagnosis in power transformers |
pp. 2201-2203 |
|
|
by : Michel B. Hell, Marcos F. S. V. D/Angelo, Guilherme I. B. da Fonseca, Neymard A. Silva and Pyramo P. Costa Jr.
Abstract: - This paper present a methodology for fault diagnosis in power transformers using an Adaptative Neuro-Fuzzy Inference System . In the development and training of the system was used a real data base of gases concentration in power transformers. |
| 221 Modified RSD Analog Digital Converter with BIST Technology |
pp. 2211-2213 |
|
|
by : Radimir Vrba, Ivo Vecera, Jan Ludvik
Abstract: - Paper deals with pipelined switched-current A/D converter designed in 0.6 im BiCMOS technology with embedded BIST features. Modified RSD redundant-sign-digit conventional-restoring algorithm was implemented what decreases the amount of high-precision components. By changing from pipeline conversion to cycling mode, less power dissipation is obtained at the expense of conversion time (less than 1 iA current consumption in sleep mode). Since the switched-current structure changes the mode of operation of current copiers, large fault coverage can be reached if creating proper design-for-test. Proposed A/D converter is suitable for conversion of the current with very low amplitude from analog into digital domain. Current mode enables operation down to 3V thus is suitable for battery powered applications. The system integrates band-gap reference and independent supervisory circuit with 1% accuracy. A/D converter is prepared to meet 1451.2 specifications. The models developed were utilized and SPICE simulations performed to verify theoretical proposals. |
| 225 A Couple of Advanced MI Applications |
pp. 2251-2254 |
|
|
by : Matjaz Gams
Abstract: - Machine intelligence (MI) systems offer several advantages over classical computer systems, but applications in real-life are not as common as they should be. We present a couple of advanced MI applications developed or being developed in our group: an employment agent, a speech agent, a semantic web speaking system, a still-mill application, an agent for OS help, an agent-based group server, and an e-commerce agent. Based on past experience, we highlight the principal advantages in the development and exploitation of the MI approach, and some problems. |
| 226 On Sizes of Mincuts in a Fibonacci Graph |
pp. 2261-2265 |
|
|
by : Mark Korenblit and Vadim E. Levit
Abstract: - The structure of mincuts of a Fibonacci graph is investigated. We show that an n-vertex Fibonacci graph has mincuts of all sizes from 2 to ceiling[(n+1)/2]. |
| 227 A Rough Sets Based Classifier for Induction Motors Fault Diagnosis |
pp. 2271-2278 |
|
|
by : Erik Bonaldi, Luiz Eduardo Borges da Silva, Germano Lambert-Torres, Levy de Oliveira
Abstract: - This paper describes the ongoing research on Rough Sets based classifier applied to Induction Motors fault diagnosis through Motor Current Signature Analysis (MCSA). The results of mechanical failures detection and how a Rough Sets based classifier is used as a monitoring system using current signature analysis in predictive maintenance are also described in this paper. |
| 229 On the Sylvester, Lyapunov and Stein equations over rngs |
pp. 2291-2295 |
|
|
by : M.C.Gouveia
Abstract: - The theory of generalized inverses is used to discuss the consistency of each of the matrix equations AX-YB=C, AX-XB=C and AXB=C, over a non commutative rng. Some explicit general solutions are also presented. |
| 233 Active Power Filter For Harmonic Current Compensation Using The Id-Iq Control Method Without PLL And With The Best Transient Time |
pp. 2331-2336 |
|
|
by : Levy Oliveira, Luiz Silva, Valberto Silva, Germano Torres, Erik Bonaldi
Abstract: - The id-iq control method are one of the most widespread control methods for active power filters. Two improvements to this method are presented: the elimination of the PLL (Phase Locked Loop) in active power filters for harmonic current compensation only and a strategy for achieving the best transient time. PLL elimination is an important simplification for reducing the computational effort in a digital implementation as well as for improving transient time. The achievement of the best transient time is essential for an efficient compensation of currents with time-varying harmonic content. The paper describes both improvements and presents simulations and experimental results. |
| 234 Equations in involution with a scalar second-order hyperbolic equation in the plane |
pp. 2341-2346 |
|
|
by : Martin Juras
Abstract: - We find necessary and sufficient conditions for a scalar second-order hyperbolic equation in the plane F(x,y,u,u_x, u_y, u_{xx}, u_{xy}, u_{yy}) =0 to admit an equation in involution of order k. |
| 236 On the commutation process of capacitor commutated converter (CCC) |
pp. 2361-2366 |
|
|
by : Angelo J. J. Rezek; Adriana A. S. Izidoro; Jocelio S. Sa
Abstract: - Series compensated commutation is obtained by insertion a capacitor between the converter transformer and the six pulse thyristorized Graetz bridge. This arrangement will able a reduction in the impedance of the commutation circuit. This can permit greater efficiency of commutation, reducing the reactive power consumption of the converter and the consequent necessity of large shunt compensation banks. An improvement in the susceptibility of the converter to commutation failure is achieved, when the converter is operating in the inverter mode. In this paper the valve commutation process will be studied and discussed taking into account the use of series compensated capacitor. |
| 237 Performance Analysis of Binary and Quaternary Modulations |
pp. 2371-2375 |
|
|
by : Rausley Souza, Sandro Fasolo, Cesar d/Avila
Abstract: - This paper presents the performance analysis of binary and quaternary modulations on a k-u nonselective fading channel. The k-u distribution is used to model a frequency-nonselective fading channel considering similar time delays for the scattered waves arriving at the receiver. The modulations analyzed are: BPSK, BFSK Coherent, BFSK Noncoherent, DPSK, QPSK, OQPSK and pi/4 DQPSK. This analysis shows that BPSK, QPSK and OQPSK present a better performance than the other modulations with respect to the average bit error probability. It will be shown that for one value of the Nakagami parameter, m, it is possible to obtain different average bit error probability performance. Thus, it permits better fit of the experimental data to the theoretical curves, by choosing the appropriates values of the k-u parameters. |
| 239 Computer generation of Generalized Numerical Ranges of Linear Operators in Indefinite Inner Product Spaces |
pp. 2391-2396 |
|
|
by : N. Bebiano, J. da Providencia Jr. and J. da Providencia
Abstract: - One of the possible generalizations of the classical numerical range of a given linear operator in an indefinite inner product space is the so-called J,C-tracial range. We present an algorithm to generate this generalized numerical range and give simple examples for illustration. |
| 240 Development of a Digital Electronic Transformer Turn Ratio (TTR) |
pp. 2401-2403 |
|
|
by : Jose Manuel Esteves Vicente; Angelo Jose Junqueira Rezek; Carlos Alberto Mohallem Guimaraes; Antonio Tadeu Lyrio de Almeida.
Abstract: - This work describes a digital instrument for measuring the transform ratio of three-phase and single-phase transformers. The operation technique allows to perform the test simultaneously in coils of the same tap. As the instrument is controlled by computer, the tests are made quickly, requiring only that the operator makes the commutation of the taps. Nowadays this instrument is being used by some manufactures of transformers, with quite satisfactory results. |
| 242 Adjoint Transformations In OTA-C Filters Using Nullors |
pp. 2421-2424 |
|
|
by : Tlelo-Cuautle E., Diaz-Mendez A.
Abstract: - A method focused on transforming an OTA-C f ilter working in voltage-mode to current-mode using nullors, is presented. First, the ideal behavior of the OTA is modeled using the nullor concept. Second, the transformation process is done by applying a set of four basic rules related to the interconnection pattern of the nullors. Third, the nullors of the transformed circuit are synthesized by OTAs. Finally, the computation of the transfer function of the given and the transformed circuit demonstrates the suitability of the method based on adjoint transformations. |
| 243 Symbolic Noise Analysis For Most Circuits Using Nullors |
pp. 2431-2434 |
|
|
by : Sanchez-Lopez C., Tlelo-Cuautle E., Diaz-Sanchez A.
Abstract: - A novel technique oriented to compute Noise Figure (NF) for MOS Transistor (MOST) circuits, is presented. The proposed method uses the features of symbolic analysis. In order to improve the computation time, a pure-nodal-analysis (PNA) method is applied by modeling all elements using the nullor. Two illustrative examples, where the NF is computed using the proposed method and HSPICE, demonstrates the suitability of the proposed method. |
| 245 A simulation and a study of random walks |
pp. 2451-2458 |
|
|
by : M.Hamada
Abstract: - Random walk model has many useful applications in the study of stochastic (probabilistic) processes including: modeling the transport of molecules in physics, modeling the locomotion of organisms in biology, and modeling the behavior over time of financial markets in economy. In this paper we introduce a visualized simulation of a random walk in d-dimensional lattice. We also introduce a numerical analysis of the d-dimensional lattice walk. A two- and three-dimension off-lattice walks are also discussed. In addition to simulating self-avoiding walks. |
| 246 Comparative analyses of spectrum and pitch modeling by HMMs applied to a Brazilian Portuguese TTS |
pp. 2461-2465 |
|
|
by : Filipe Barbosa, Guilherme Pinto, Ranniery Maia, Fernando Resende
Abstract: - This work presents a Brazilian Portuguese TTS based on HMM modeling of spectrum and pitch. A major advantage of HMM-based TTS systems is the possibility of fast speaker adaptation. During the HMM training, mel-cepstral coefficients are used to represent the vocal tract and pitch information is obtained through the autocorrelation method. Comparative analysis show the effectiveness of the proposed HMM-based TTS, as well as the impact of HMM modeling for spectrum, and pitch. |
| 247 A New Multivariable Robust Model Reference Adaptive Controller |
pp. 2471-2476 |
|
|
by : Carlos Richter and Hilton Grundling
Abstract: - This paper proposes a new multivariable model reference adaptive controller (MIMO RMRAC), which consists of two parts: the first part involves the characterization of the integral structure of the modeled part of the plant, and the associated parameterization of the controller structure; and the second part involves the development of a robust adaptive law based on a modified least-squares algorithm for adjusting the controller parameters so that the closed-loop plant is globally stable despite the presence of unmodeled dynamics and bounded disturbances. |
| 251 Three Dimensional Modeling of a Virtual Medical Office in a Medical Area |
pp. 2511-2514 |
|
|
by : R. A. Farias, L. M. Brasil, I. M. L. Araujo, C. B. Melo
Abstract: - The main objective of this paper is to provide information on the development of an interface for a Virtual Medical Office, for application in a specific medical area. Apart from the tree dimensional modeling of the virtual environment, a humanoid figure will be mapped and applied to the navigation in the Virtual Medical Office. The system itself supports three different levels of users: the specialist, the patient and the student, and will have the interface developed for VRML application, so it can be accessible in the World Wide Web. In addition to the modeling of the human shape, other medical domains will also have their proper systems mapped, so that the Virtual Medical Office may become increasingly complete in terms of general medical information. |
| 253 Analog Implementation of MOS-Translinear Morlet Wavelets |
pp. 2531-2535 |
|
|
by : Carlos Sanchez-Lopez , Alejandro Diaz-Sanchez and Esteban Tlelo-Cuautle
Abstract: - The design of a low-voltage current-mode Morlet Wavelet, using MOS transistors in weak inversion, is presented. The proposed design is based on two translinear building blocks: a normalized gaussian-function generator and a four-quadrant analog-multiplier. Simulation results using BSIM3.v3 model for a 0.6um AMS process parameters, in a CADENCE environment, are presented. |
| 255 A 1.35 GHz CMOS Wideband Frequency Synthesizer |
pp. 2551-2555 |
|
|
by : Esdras Juarez-Hernandez and Alejandro Diaz-Sanchez
Abstract: - The design and simulation of a 1.35 GHz CMOS frequency synthesizer for a double band receiver is presented. The proposed synthesizer is based in a wideband PLL topology with a high frequency reference, giving as result low phase noise, fast switching time, a low divider ratio and a reduction in the chip area. Besides, the use of a novel charge-pump circuit with positive feedback and current reuse allows a further reduction in both, chip area and power consumption, making the structure desirable for high-frequency low-voltage phase-locked loops. |
| 256 Analog Implementation of Nonlinear Mean Filters |
pp. 2561-2565 |
|
|
by : Rogelio De Jesús-Peregrina and Alejandro Díaz-Sánchez
Abstract: - The implementation of a family of nonlinear analog filters for image applications, by using MOS-translinear current mode circuits, is presented. Versatility and low power consumption characteristics of MOS transistors operating in weak inversion are used in the reported filter applications. HSPICE simulations have been carried out using 1.6 ƒYm CMOS level 49 parameters. |
| 257 Ensembles of Support Vector Machines for Classification Tasks with Reduced Training Sets |
pp. 2571-2578 |
|
|
by : Clodoaldo Lima, Andre Coelho, Fernando Von Zuben
Abstract: - Support vector machines (SVMs) tackle classification and regression problems by non-linearly mapping input data into high-dimensional feature spaces, wherein a linear decision surface is designed. Even though the high potential of these techniques has been demonstrated, their applicability has been swamped by the necessity of the a priori choice of the kernel function to realize the non-linear mapping, which, sometimes, turns to be a complex and non-effective process as each kernel has its pros and cons. In a previous work, we have conceived ensembles of SVMs (E-SVMs) in order to alleviate the performance bottlenecks incurred with the “kernel function choice” problem. By this means, different component networks (single SVMs) with distinct kernel functions, such as polynomials or radial basis functions, may be created and properly combined into the same neural structure. E-SVMs have already been applied to a number of regression problems, yielding significantly improved generalization performance. In this paper, we extend the E-SVM methodology to also address classification tasks. Some experiments are conducted to assess E-SVM capabilities on a well-known classification problem with reduced training set (intertwined spirals). |
| 258 A Second Generation Low-Voltage Current Conveyor |
pp. 2581-2584 |
|
|
by : Juan Lopez-Hernandez, Jose Alejandro Diaz-Mendez and Alejandro Diaz-Sanchez
Abstract: - A Low-Voltage/Low-Power rail-to-rail Second Generation Current Conveyor is presented. The CCII is implemented using two techniques: MOS Transistors in weak inversion, which allows the use of small Ib, and Floating Gates, to obtain an extended dynamic range operation. The concept of Partial Positive Feedback is used in the implementation of the required OTA. |
| 259 A Neural Approach for Load Torque Identification in Electrical Machinery |
pp. 2591-2596 |
|
|
by : Alessandro Goedtel, Ivan Nunes Da Silva, Paulo Jose A. Serni
Abstract: - The induction motors are largely used in several industry sectors. The dimensioning of an induction motor has still been inaccurate because in most of the cases the load behavior in its shaft is completely unknown. The proposal of this paper is to use artificial neural networks as tool for dimensioning of induction motors rather than conventional methods, which use classical identification techniques and mechanical load modeling. Simulation results are also presented to validate the proposed approach. |
| 260 An Application of Artificial Neural Networks in Brake Light Design for the Automobile Industry |
pp. 2601-2606 |
|
|
by : Antonio Vanderlei Ortega, Ivan Nunes Da Silva
Abstract: - The advantages offered by the electronic component LED (Light Emitting Diode) have caused a quick and wide application of this device in replacement of incandescent lights. However, in its combined application, the relationship between the design variables and the desired effect or result is very complex and it becomes difficult to model by conventional techniques. This work consists of the development of a technique, through artificial neural networks, to make possible to obtain the luminous intensity values of brake lights using LEDs from design data. |
| 261 Tuning of Fuzzy Inference Systems Through Unconstrained Optimization Techniques |
pp. 2611-2616 |
|
|
by : Rogerio Andrade Flauzino, Ivan Nunes Da Silva
Abstract: - This paper presents a new methodology for the adjustment of fuzzy inference systems. A novel approach, which uses unconstrained optimization techniques, is developed in order to adjust the free parameters of the fuzzy inference system, such as its own parameters of the membership function, and the weight of the inference rules. This methodology is interesting, not only for the results presented and obtained through computer simulations, but also for its generality concerning to the kind of fuzzy inference system used. Therefore, this methodology is expandable either to the Mandani architecture or also to that suggested by Takagi-Sugeno. The validation of the presented methodology is accomplished through estimation of time series. More specifically, the Mackey-Glass chaotic time series is used for the validation of the proposed methodology. |
| 263 Image Processing Noise Removal using a Cellular Neural Network |
pp. 2631-2634 |
|
|
by : Jan Ludvik - Radimir vrba
Abstract: - The cellular neural network problem is nowadays a well-known theory. This paper describes some problems with a CMOS implementation on a chip. Some designs of a cell circuit is designed a simulated in HSpice simulator. The microelectronic structure is designed with these assumptions: simple structure, low number of transistor, small occupied area on the chip and as fast as possible. The structure is designed in the CMOS technology Alcatel Mietec 0.35mm. A functionality of the network for nose removing is proved on the network 3/3 cells and on the network 8/8 cells, both networks have the same neuron with fixed synaptic weights. This network 8/8 cells has an added functions – the horizontal and vertical line detection. The solution of the microelectronic structure is in this paper, except the linear resistors in the neuron. |
| 264 Map-based variable rate applicator of liquid fertilizers based on artificial neural networks identification techniques |
pp. 2641-2646 |
|
|
by : Jose Alfredo Ulson, Roberta S. Ulson, Andre N. de Souza, Ivan N. da Silva
Abstract: - Variable rate fertilization aims to improve fertilizer use efficiency and reduce leaching by varying the fertilizer rates according to the needs of each portion of the crop and the soil. The application of liquid fertilizers through variable rate techniques implemented by classical control approaches needs a electromagnetic flow meter in the primary controlled variable. This paper proposes an intelligent control system based on Artificial Neural Networks of the type multilayer perceptron for the identification and control the fertilizer flow rate. In this approach, there is no flow meter since the control is made through secondary variables. The neural network training is made by the algorithm of Levenberg-Marquardt with training data obtained from laboratory measurements. The results indicate an accurate, fast, stable and low cost control system for variable rate applicators. |
| 268 Wavelet-based Solution to Time-Dependent Two-Point Initial Boundary value Problems with Non-Periodic Boundary Conditions Involving Advection |
pp. 2681-2689 |
|
|
by : Rajiv Nekkanti
Abstract: - The Wavelet solution for boundary-value problems is relatively new and has been mainly restricted to the solutions in data compression, image processing and recently to the solution of differential equations with periodic boundary conditions. This paper is concerned with the wavelet-based Galerkin solution to two-point boundary-value problems involving advection with non-periodic boundary conditions. The wavelet method can offer several advantages in solving the boundary-value problems than the traditional methods such as Fourier series, Finite Differences and Finite Elements by reducing the computational time near singularities because of its multi-resolution character. In order to demonstrate the wavelet technique to non-periodic boundary value problems, we have now extended our prior research of solution of hyperbolic, elliptic and parabolic problems with non-linear boundary conditions to diffusion problems involving advection: a simple diffusion-advection and a nonlinear advection (Burgers’ Equation). The results of the wavelet solutions are examined and they are found to compare favorably to the exact solutions. This paper on the whole indicates that the wavelet technique is a strong contender for solving two point boundary value problems with non-periodic conditions involving advection. |
| 270 A Transformational Approach for Legacy Systems' Evolution |
pp. 2701-2709 |
|
|
by : Maseud Rahgozar, Farhad Oroumchian
Abstract: - The evolution of the Legacy Information Systems (LIS) is a critical issue for many organizations world wide. A Large number of organizations for their daily activities depend on the business critical applications that have been developed over the last two decades or more. They mostly run on old software and hardware technology tools and environments. They are hard to modify, expensive to maintain and difficult to integrate with new technology tools and programs. They need to be evolved into modern environments. This paper suggests guidelines for an optimal transformation of legacy systems into Unix-RDBMS architectures, based on many years of professional experiences of the authors in the area. |
| 271 Automatic Evolution of Legacy Data Objects |
pp. 2711-2718 |
|
|
by : Maseud Rahgozar, Farhad Oroumchian
Abstract: - The modernization of the Legacy Information Systems (LIS) is a critical issue for many organizations world wide. The successful migration of the legacy data stored in the old data formats is a challenging issue with respect to backward compatibility and future extendibility. By migration, we mean translating legacy data and related programs to native data and programs running on modern platforms such as Unix (or NT). Currently, in most migration projects, converting all legacy data objects (traditionally stored in flat and indexed files) to RDBMS tables is considered to be unrealistic and out of question because of the expected performance problems. While in our experience, those legacy data objects have to be converted to the modern database (RDBMS) tables and fully integrated in the Global Information System schema. Otherwise those data objects will not be ready for the application of novel technology tools and soon will become a new bottle neck in the system. This is, not only to create a unified schema of the new Information System, but also to take full advantage of transaction management and recovery services provided by the database management systems. In order to guarantee performance, efficiency, share ability and ease of future enhancements, the legacy data has to be fully normalized too. This paper examines the issues concerning the migration of legacy data objects to RDMS environment and offers a practical approach. |
| 273 Crazy Rollers |
pp. 2731-2733 |
|
|
by :
Jose Carlos Teixeira, Natalia Providencia, Joao Da Providencia, Goncalo Carvalho, Joao Da Providencia Jr
Abstract: - The cars we are familiar with have circular wheels. Here, we consider cars whose wheels are not circular and nevertheless these cars move smoothly. A mathematical development characterizing the condition for a smooth motion of exotic wheels is presented. This mathematical development has been tested on different simulation environments. Finally, we introduce a specific virtual environment developed to support an easy presentation of mathematical conceps related with this situation. |
| 275 Analysis of a Decoding Approach for Goppa Codes |
pp. 2751-2754 |
|
|
by : Lirida Alves de Barros Naviner and Zouhair Belkoura
Abstract: - Algebraic-geometry family of codes contains sequences with excellent asymptotic behaviour, but few work have been reported in the literature concerning their hardware implementation. In this paper, we investigate an algorithm for decoding AG codes under the hardware feasibility point of view. We modify the original strategy in order to obtain a new structure more suitable for hardware implementation |
| 277 An efficient recovery technique using global buffer on SAN environments |
pp. 2771-2777 |
|
|
by : Choon seo Park, Gyoung bae Kim, Yong ju Lee
Abstract: - The shared disk file systems use a technique known as file system journaling to support recovery of metadata on the SAN(Storage Area Network). In the existing journaling technique, the metadata that is dirtied by one host must be updated to disk space before some hosts access it. The system performance is decreased because the disk access number is increased. In this paper, we describe a new recovery technique using a global buffer to decrease disk I/O. It transmits the dirtied metadata into the other hosts through Fibre Channel network on the SAN instead of disk I/O and supports recovery of a critical data by journaling a data as well as metadata |
| 280 Biological System of Analysis of Systems Mathematics |
pp. 2801-2806 |
|
|
by : Hugh R. MacMillan, Mike J. McConnell, Kaihsu Tai
Abstract: - We present two examples of computational cellular biology that provide perspective on the complexity of creating predictive models of cell behaviors as they emerge from the interaction of molecular species. The first is a model of the diffusion and reaction of neurotransmitter in a neuromuscular junction using a continuum based finite element formulation. Whereas this formulation accounts for spatial variation of neurotransmitter concentration, the single unknown, the second example is a system of ordinary differential equations to describe the biochemical state of an embryonic mouse neuron in relation to the observed behaviors of death, division, or differentiation. Each model, born of a deterministic mathematical perspective, is early in its own evolution as it grows to reflect true biology. The necessarily organic nature of these models, in simultaneouslly incorporating and stimulating understanding, is the thrust of the perspective they provide on the future of computational cellular biology. Whereas in written form, this material must be presented linearly, live presentation is done in hypertext format to more suitably portray the interconnected issues and methods on a multiplicity of scales. |
| 281 A Three-Phase Uninterruptible Power Supply using Multivariable Repetitive Robust Model Reference Adaptive Control |
pp. 2811-2816 |
|
|
by : Carlos Richter, Emerson Carati and Hilton Grundling
Abstract: - This paper presents a repetitive multivariable robust model reference adaptive controller (MIMO RMRAC-RP) applied to a three-phase uninterruptible power supply (UPS). Using ab0 transformation and balanced three-phase load, the plant can be considered weakly coupled, and then a multivariable law may have its parameters reduced in number, reducing the computational effort to adapt them. For this MIMO RMRAC-RP with reduced number of parameters, the augmented error equation is written and the adaptation algorithm convergence mathematical proves as well as the proof of the overall closed-loop system stability are developed, despite the presence of unmodeled dynamics and bounded disturbances. Experimental results confirm good performance for linear and non-linear balanced three-phase loads. |
| 282 On level-compatible algebra functions and their transformers |
pp. 2821-2828 |
|
|
by : Zhuhan Jiang
Abstract: - We develop the mathematical theory of algebra functions on $A^*$ for a finite alphabet $A$, such that the functions are level-compatible when they are restricted to the different levels $m$ according to $A^m$. We shall first establish the fundamentals and the structure of such function spaces and the related properties, and propose and study the all important level-preserving transformers there. We shall then look into the the automaton representations of the level-compatible algebra functions, the characterisation of the level-preserving transformers, as well as the potential applications at calculation of eal-valued functions, fractal generations and even the compression of natural images. |
| 283 Rules extraction via neural networks previously trained |
pp. 2831-2836 |
|
|
by : Luis Zarate, Alexandra Costa, Elisangela Maia
Abstract: - In this paper, two methods for extraction of knowledge rules through Artificial Neural Networks, with continuous activation functions are presented. Those rules are extracted from neural networks previously trained and of the sensitivity factors obtained by the differentiation of a neural network. The rules can be used when analytic models of the physical processes lead to equations of difficult numerical and analytical solutions. In the operation of industrial processes, the rules can help for the taking of decision of less experienced operators. The proposed methods will be applied for the obtaining of knowledge rules for the cold rolling process. |