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Automated Weight Tuning for Rule-Based Knowledge Bases
Valenta, Jan ; Pokorný, Miroslav (referee) ; Zbořil, František (referee) ; Jirsík, Václav (advisor)
This dissertation thesis introduces new methods of automated knowledge-base creation and tuning in information and expert systems. The thesis is divided in the two following parts. The first part is focused on the legacy expert system NPS32 developed at the Faculty of Electrical Engineering and Communication, Brno University of Technology. The mathematical base of the system is expression of the rule uncertainty using two values. Thus, it extends information capability of the knowledge-base by values of the absence of the information and conflict in the knowledge-base. The expert system has been supplemented by a learning algorithm. The learning algorithm sets weights of the rules in the knowledge base using differential evolution algorithm. It uses patterns acquired from an expert. The learning algorithm is only one-layer knowledge-bases limited. The thesis shows a formal proof that the mathematical base of the NPS32 expert system can not be used for gradient tuning of the weights in the multilayer knowledge-bases. The second part is focused on multilayer knowledge-base learning algorithm. The knowledge-base is based on a specific model of the rule with uncertainty factors. Uncertainty factors of the rule represents information impact ratio. Using a learning algorithm adjusting weights of every single rule in the knowledge base structure, the modified back propagation algorithm is used. The back propagation algorithm is modified for the given knowledge-base structure and rule model. For the purpose of testing and verifying the learning algorithm for knowledge-base tuning, the expert system RESLA has been developed in C#. With this expert system, the knowledge-base from medicine field, was created. The aim of this knowledge base is verify learning ability for complex knowledge-bases. The knowledge base represents heart malfunction diagnostic base on the acquired ECG (electrocardiogram) parameters. For the purpose of the comparison with already existing knowledge-basis, created by the expert and knowledge engineer, the expert system was compared with professionally designed knowledge-base from the field of agriculture. The knowledge-base represents system for suitable cultivar of winter wheat planting decision support. The presented algorithms speed up knowledge-base creation while keeping all advantages, which arise from using rules. Contrary to the existing solution based on neural network, the presented algorithms for knowledge-base weights tuning are faster and more simple, because it does not need rule extraction from another type of the knowledge representation.
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Numerical solution of index-2 differenial-algebraic equations
Kroulíková, Tereza ; Opluštil, Zdeněk (referee) ; Zatočilová, Jitka (advisor)
This bachelor´s thesis deals with numerical solution of differential-algebraic equations. At first these equations are described theoretically and their basic properties are presented. Main attention is paid to index and the most used indexes are described in details. Then the thesis concentrates on numerical solution of Hessenberg forms index-2 differential-algebraic equations. Implicit Runge-Kutta methods and backward differentiation formulas are derived. Those are used for solution of index-2 differential-algebraic equations.
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Automatic hp-adaptivity on Meshes with Arbitrary-Level Hanging Nodes in 3D
Kůs, Pavel
The thesis is concerned with theoretical and practical aspects of the hp- adaptive finite element method for solving elliptic and electromagnetic prob- lems described by partial differential equations in three spatial dimensions. Besides the standard element refinements, the hp-adaptivity allows indepen- dent adaptation of degrees of the polynomial approximation as well. This leads to exponentially fast convergence even for problems with singularities. The efficiency of the hp-adaptivity is enhanced even more by the ability of the algorithm to work with meshes with arbitrary-level hanging nodes. This generality, however, leads to great complexity of the implementation. There- fore, the thesis concentrates on the mathematical analysis of algorithms that have led to successful implementation of the method. In addition, the the- sis discusses the numerical integration in 3D and the implementation of the method itself. Finally, numerical results obtained by this new implemen- tation are presented. They confirm advantages of hp-adaptivity on meshes with arbitrary-level hanging nodes. 1
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HP-FEM for Coupled Problems in Fluid Dynamics
Dubcová, Lenka
of dissertation hp-FEM FOR COUPLED PROBLEMS IN FLUID DYNAMICS Lenka Dubcová The thesis is concerned with the solution of multiphysics problems de- scribed by partial differential equations using higher-order finite element method (hp-FEM). Basics of hp-FEM are described, together with some practical details and challenges. The hp-adaptive strategy, based on the reference solution and meshes with arbitrary level hanging nodes, is dis- cussed. The thesis is mainly concerned with the extension of this strategy to monolithical solution of coupled multiphysics problems, where each physical field exhibits different qualitative behavior. In such problems, each physical field is discretized on an individual mesh automatically obtained by the adaptive algorithm to suit the best the corresponding so- lution component. Moreover, the meshes can change in time, following the needs of the solution components. All described methods and tech- nologies are demonstrated on several examples throughout the thesis, where comparisons with traditionally used approaches are shown.
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Automatic Computation Control
Opálka, Jan ; Šátek, Václav (referee) ; Kunovský, Jiří (advisor)
This work deals with the automatic control of numerical calculations. The reader is acquainted with the numerical solution of differential equations and the parallel, serial, and series-parallel numerical integrator. The practical aim of this work is to design control circuits for the three mentioned variants of integrators. The design includes the development of a software simulator of the control circuit for the series-parallel integrator in a fixed point.
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Driver of Semiconductor laser for 1Gbit/s
Melichárek, Radek ; Vařacha, František (referee) ; Prokeš, Aleš (advisor)
This thesis describes a design of a driver for a specific type of laser VCSEL. Models for simulation in PSpice OrCAD have been developed for this type of laser. The qualities of the designed driver aim to be equal to the integrated drivers that are available and to remove some of their drawbacks. It consists of the following components: input LVPECL receiver/driver, differential amplifier, fixed source of a modulation current, circuit of automatic power control. Regulation of the modulation current is dealt with atypically using an aptly selected input LVPECL receiver/driver which enables to control the voltage amplitude on its output by means of voltage. The thesis also describes different types of coupling between laser and driver. The most appropriate alternative is selected taking into consideration the unconventional design of the driver. The connection of the driver is supplemented by a microcontroller which secures control of output optical power by means of a serial bus RS232.
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Designing an automated workplace for charge and high-impedance measurement
Nemček, Jakub ; Bartušek, Karel (referee) ; Gescheidtová, Eva (advisor)
This barchelor thesis is about Desig an automated workplace forchargeable and high-impedant measurements. This automated workplace is realized by tubular aspiration capacitor, which is connected via differential converter U/I to data acquisition switch unit HP 34970A. The data acquisition switch unit HP 34970A is also connected by serial line RS-232 to Computer (PC), on which the directed program Agilent VEE Pro 7.0 is installed. To the right connection data acquisition switch unit HP 34970A and PC is necessary to set the same parameters on data acquisition switch unit HP 34970A, such in I/O config and also in Instrument manager too. In Instrument manager is requisite to set Plug und Play driver for data acquisition switch unit HP 34970A. The programing in Agilent VEE Pro 7.0 is based on object oriented programming. To start the program press the button “START“ and automatic measuring of concentration air ionts, will start the process (the trend is marked to the graph). The program is indicated if the ventilator blows an air in the aspiration capacitor and draws the trend of voltage on this ventilator to the graph. To stop the program press the buton “STOP“. Measured data are exported to program Excel. For the export Excel has to be running before the process. The function is verifing by measuring of background negativ a positiv ionts, by influence of position the source of ionts behind the aspiration capacitor and by influence of materials (metal plate, paper carton, wood, conductive paint) to the concentration of negativ ionts.
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Electric Circuits Simulations
Šulc, Jiří ; Šátek, Václav (referee) ; Kunovský, Jiří (advisor)
The aim of this bachelor's thesis was the design of elementary graphic computational editor in which quality schema designs of electrical circuits can be created easily and fast. The application is further able to automatically generate the system of equations describing the designed circuit which can be used in the TKSL simulation system for displaying of the solutions. The application is designed for student's use in order to support the teaching of the Circuit Theory. The bachelor's thesis further deals with the problem solving of differential equations by the way of numerical integration methods with direct use of the Taylor series. The complexity of the analytical and numerical algorithm of the differential equations in solving electrical circuits is analyzed on the examples.
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Integration patterns and its automatic evaluation
Krsička, D. ; Šárek, Milan
This paper presents a research project on the integration of information systems in medicine. The area of research interest was specified - optimization of architecture linking of medical information systems. Featured topic is a part of the problems of architecture management in health information systems (so-called Enterprise Architecture).
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