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The purpose of this thesis is to design, implement and analyse a hybrid genetic algorithm for solving the MAX-3SAT problem. The problem is a well known NP-complete decision problem. Solving this type of problems is highly motivated by its practical use in industry. The main field of 3SAT solver application ranges from integrated circuit delay optimization to FPGA routing. See section 1.9 for details on practical applications of the MAX- 3SAT solver. The idea behind this hybrid genetic algorithm, is to see just when and how much of local search can still prove beneficial to the overall solution quality. In the results section 4.4, we have shown that this algorithm performs best when the local search is applied periodically and with our best run results (presented in section 4.6) we came very close to a similar implementation described in [14]. Our best average run time on the biggest test instances was trailing behind aforementioned article by about 30 percent. The reason, why our average running time is fairly close to the aforementioned imple- mentation, lies in exploiting parallelism. We used a simple parallelization technique of local searching, which is described in section 4.2. Moreover, our solution quality - that is the number of unsatisfied clauses, was pretty much as good as the one reported in [14]. Ours was worse by only 0,6 percent. It is important to point out that we used exactly the same test instances as used in [14].

ENGLISH: Knowledge of the kinds of organisms eaten by tunas, and the relative importance of different kinds of organisms in different situations, is of importance to our understanding of regional and local aggregations and of the behavior of the tropical tunas. Determination of the relative importance of benthic forms in the stomachs of tunas captured in the vicinity of islands and offshore banks, compared with the forms found in the stomachs of those from oceanic areas, distant from these shoal areas, is useful to the understanding of the mechanisms by which the islands and banks attract tuna. A thorough knowledge of the diet may also reveal more about the seasonal and annual variations in the distribution of these fish along the coasts of Mexico, Central America and elsewhere. A knowledge of the diet of the tunas is basic to quantitative studies of the zooplankton and nekton in the Eastern Pacific Ocean with reference to the production of tunas. Studies of the diet of the tropical tunas by examination of stomach contents was, therefore, commenced in late 1957. SPANISH: El conocimiento de las clases de organismos de que se alimentan los atunes, y la importancia relativa de las diferentes clases de organismos en situaciones diferentes, es de valor para nuestra comprensión de las agrupaciones regionales y locales, y de los hábitos de los atunes tropicales. La determinación de la importancia relativa de las formas bénticas en los estómagos de los atunes capturados en la vecindad de las islas y de los bancos apartados de la costa, comparadas con las formas encontradas en los estómagos de los atunes procedentes de áreas oceánicas, distantes de estas áreas poco profundas, es útil para comprender el mecanismo por el cual las islas y los bancos atraen al atún. Un conocimiento completo de la dieta puede revelar también algo más acerca de las variaciones estacionales y anuales en la distribución de estos peces a lo largo de las costas de México, América Central y otras partes. El conocimiento de la dieta del atún es básico para los estudios cuantitativos del zooplancton y del necton en el Océano Pacífico Oriental, con referencia a la producción de los atunes. El estudio de la dieta de los atunes tropicales mediante el examen del contenido estomacal, fué comenzado, por lo tanto, a fines de 1957. This article is bilingual and contains both Spanish and English translations.