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Coevolutionary Algorithms Statistical Analysis Tool
Urban, Daniel ; Zachariášová, Marcela (referee) ; Drahošová, Michaela (advisor)
This bachelor thesis contains a theoretical basis that introduces evolutionary algorithms, genetic programming, coevolutioanary algorithms and methods for statistical evaluation. Furthermore, this work deals with the design and implementation of tool with graphical user interface, which allows the analysis of coevolutioanary algorithm for various parameters and also its statistical evaluation. The functionality of the implemented tool has been tested on data obtained from an external program performing evolutionary design of image filters with the use of the coevolution of tness predictors. The resulting graphs and statistics allow easy comparison of the progress and results for each program run.
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Automated Design Methodology for Approximate Low Power Circuits
Mrázek, Vojtěch ; Bosio, Alberto (referee) ; Fišer, Petr (referee) ; Sekanina, Lukáš (advisor)
Rozšiřování moderních vestavěných a mobilních systémů napájených bateriemi zvyšuje požadavky na návrh těchto systémů s ohledem na příkon. Přestože moderní návrhové techniky optimalizují příkon, elektrická spotřeba těchto obvodů stále roste díky jejich složitosti. Nicméně existuje celá řada aplikací, kde nepotřebujeme získat úplně přesný výstup. Díky tomu se objevuje technika zvaná aproximativní (přibližné) počítání, která umožňuje za cenu zanesení malé chyby do výpočtu významně redukovat příkon obvodů. V práci se zaměřujeme na použití evolučních algoritmů v této oblasti. Ačkoliv již tyto algoritmy byly úspěšně použity v syntéze přesných i aproximativních obvodů, objevují se problémy škálovatelnosti - schopnosti aproximovat složité obvody. Cílem této disertační práce je ukázat, že aproximační logická syntéza založená na genetickém programování umožňuje dosáhnout vynikajícího kompromisu mezi spotřebou a chybou. Byla provedena analýza čtyř různých aplikacích na třech úrovních popisu. Pomocí kartézského genetického programování s modifikovanou reprezentací jsme snížili spotřebu malých obvodů popsaných na úrovni tranzistorů použitelných například v technologické knihovně. Dále jsme zavedli novou metodu pro aproximaci aritmetických obvodů, jako jsou sčítačky a násobičky, popsaných na úrovni hradel. S využitím metod formální verifikace navíc celý návrhový proces umožňuje garantovat stanovenou chybu aproximace. Tyto obvody byly využity pro významné snížení příkonu v neuronových sítích pro rozpoznávání obrázků a v diskrétní kosinově transformaci v HEVC kodéru. Pomocí nové chybové metriky nezávislé na rozložení vstupních dat jsme navrhli komplexní aproximativní mediánové filtry vhodné pro zpracování signálů. Disertační práce reprezentuje ucelenou metodiku pro návrh aproximativních obvodů na různých úrovních popisu, která navíc garantuje nepřekročení zadané chyby aproximace.
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Evolutionary Design of Filters for Signal Processing
Dobiš, Tomáš ; Hrbáček, Radek (referee) ; Dobai, Roland (advisor)
Kalman filter is used for signal filtering dependent on filter configuration and prediction of values. It's configuration is difficult and requires experiences of mathematician. This thesis deals with implementation of method for signal processing with use of Cartesian genetic programming, which advantage includes the automated configuration of filter. Final method is compared on multiple testing examples with Kalman filter. From results we can infer, that implemented method works comparatively efficient on periodic and exponential signal inputs, and works significantly better on constant signal inputs than Kalman filter.
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Evolutionary Design for Circuit Approximation
Dvořáček, Petr ; Vašíček, Zdeněk (referee) ; Sekanina, Lukáš (advisor)
In recent years, there has been a strong need for the design of integrated circuits showing low power consumption. It is possible to create intentionally approximate circuits which don't fully implement the specified logic behaviour, but exhibit improvements in term of area, delay and power consumption. These circuits can be used in many error resilient applications, especially in signal and image processing, computer graphics, computer vision and machine learning. This work describes an evolutionary approach to approximate design of arithmetic circuits and other more complex systems. This text presents a parallel calculation of a fitness function. The proposed method accelerated evaluation of 8-bit approximate multiplier 170 times in comparison with the common version. Evolved approximate circuits were used in different types of edge detectors.
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Competitive Coevolution in Cartesian Genetic Programming
Skřivánková, Barbora ; Petrlík, Jiří (referee) ; Drahošová, Michaela (advisor)
Symbolic regression is a function formula search approach dealing with isolated points of the function in plane or space. In this thesis, the symbolic regression is performed by Cartesian Genetic Programming and Competitive Coevolution. This task has already been resolved by Cartesian Genetic Programming using Coevolution of Fitness Predictors. This thesis is concerned with comparison of Coevolution of Fitness Predictors with simpler Competitive Coevolution approach in terms of approach effort. Symbolic regression has been tested on five functions with different complexity. It has been shown, that Competitive Coevolution accelerates the symbolic regression task on plainer functions in comparison with Coevolution of Fitness Predictors. However, Competitive Coevolution is not able to solve more complex functions in which Coevolution of Fitness Predictors succeeded.
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Coevolution of Image Filters and Fitness Predictors
Trefilík, Jakub ; Hrbáček, Radek (referee) ; Drahošová, Michaela (advisor)
This thesis deals with employing coevolutionary principles to the image filter design. Evolutionary algorithms are very advisable method for image filter design. Using coevolution, we can add the processes, which can accelerate the convergence by interactions of candidate filters population with population of fitness predictors. Fitness predictor is a small subset of the training set and it is used to approximate the fitness of the candidate solutions. In this thesis, indirect encoding is used for predictors evolution. This encoding represents a mathematical expression, which selects training vectors for candidate filters fitness prediction. This approach was experimentally evaluated in the task of image filters for various intensity of random impulse and salt and pepper noise design and the design of the edge detectors. It was shown, that this approach leads to adapting the number of target objective vectors for a particular task, which leads to computational complexity reduction.
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Evolutionary Circuit Design at the Transistor Level
Žaloudek, Luděk ; Vašíček, Zdeněk (referee) ; Sekanina, Lukáš (advisor)
This project deals with evolutionary design of electronic circuits with an emphasis on digital circuits. It describes the theoretical basics for the evolutionary design of circuits on computer systems, including the explanation of Genetic Programming and Evolutionary Strategies, possible design levels of electronic circuits, CMOS technology overview, also the overview of the most important evolutionary circuits design methods like development and Cartesian Genetic Programming. Next introduced is a new method of digital circuits design on the transistor level, which is based on CGP. Also a design system using this new method is introduced. Finally, the experiments performed with this system are described and evaluated.
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Hash Function Design Using Genetic Programming
Michalisko, Tomáš ; Piňos, Michal (referee) ; Sekanina, Lukáš (advisor)
This thesis deals with automated design of hash functions using Cartesian genetic programming. The chosen method for collision resolution is cuckoo hashing. Three variants of hash function encodings were compared. Experiments were performed with datasets containing network flows. The most suitable parameters of CGP, including the function set, were determined. The best evolved hash functions achieved comparable results to the functions designed by experts. The main finding is that hash functions consisting of 64-bit operations achieve the best results.
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A Tool for Visual Analysis of Circuit Evolution
Staurovská, Jana ; Minařík, Miloš (referee) ; Sekanina, Lukáš (advisor)
The main goal of the master's thesis is to compose a study on cartesian genetic programming with focus on evolution of circuits and to design a concept for visualisation of this evolution. Another goal is to create a program to visualise the circuit evolution in cartesian genetic programming, its generations and chromosomes. The program is capable of visualising the changes between generations and chromosomes and comparing more chromosomes at once. Several user cases had been prepared for the resulting program.
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Genetic Relatedness Analysis of Approximate Circuits
Krejčík, Vojtěch ; Mrázek, Vojtěch (referee) ; Sekanina, Lukáš (advisor)
The goal of this thesis is analyzing a large library of approximate circuits (EvoApproxLib) which was created using an evolutionary algorithm and used as a source of genetic data for the purposes of this thesis. More specifically it is a relatedness search in a file containing 24 912 8-bit approximate multipliers which were created by evolution from six different fully functioning parent implementations of multiplication. Gate counts and existence of 16 specific subcircuits were used as relatedness indicators. Various classifiers for assigning multipliers to one of six classes corresponding to parent implementations were trained based on these indicators. A classification success rate of up to 77% was achieved using said indicators. The results of this work show that combinations of specific subcircuits are a strong indicator for identifying which parent circuit the given approximate circuit comes from.
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