1,721,039 research outputs found
Computação evolutiva aplicada a problemas inversos com preservação da especialidade na representação dos indivíduos
Full text linkTese (doutorado) - Universidade Federal de Santa Catarina, CentroTecnológico. Programa de Pós-Graduação em Engenharia ElétricaO presente trabalho estuda a utilização de representações espaciais em engenhos de computação evolutiva, como ferramenta para a solução numérica de problemas inversos. A tese se inicia descrevendo a computação evolutiva e mostrando algumas técnicas de otimização convencional. A seguir são apresentados os problemas inversos utilizados para estudo e para o desenvolvimento da metodologia de seu tratamento: condutividade geomagnética, transmissão de calor e de condutividade térmica. Seguem-se resultados numéricos obtidos para o primeiro deles, na comparação de uma abordagem clássica com regularização versus a otimização evolutiva. Citam-se alguns resultados obtidos para os outros dois problemas. Finalmente, conclui-se afirmando que o método evolutivo quando aplicado aos problemas inversos aqui estudados, nos quais as soluções possuem relações espaciais de vizinhança, é eficaz e robusto quanto aos parâmetros, quanto à inicialização e em relação ao ruído, tendo uma eficiência computacional aceitável
Układ stabilizujący prowadniki szybowe opis patentowy nr 147148 /
No full textZgłoszono 30 maja 1985 r.Zgłoszenie ogłoszono 2 grudnia 1986 r.Opublikowano 29 kwietnia 1989 r.Nr zgłosz. P 253743.Tyt. z ekranu tyt.Pozostali współtwórcy wynalazku: Józef Haneel, Andrzej Wójoicki, Mieczysław Michalewicz, Zbigniew Maj.Dostępny także w wersji drukowanej.Tryb dostępu: Internet
A parallel ant colony optimization algorithm based on crossover operation
No full textIn this work, we introduce a new parallel ant colony optimization algorithm based on an ant metaphor and the crossover operator from genetic algorithms.The performance of the proposed model is evaluated usingwell-known numerical test problems and then it is applied to train recurrent neural networks to identify linear and nonlinear dynamic plants. The simulation results are compared with results using other algorithms
Relational databases with set-valued attributes
No full textIn this thesis, we investigate the use of sets in the relational model. In particular, we look at two separate appproaches. The first approach involves using collective sets as a collection of discrete data elements, while the second approach involves using disjunctive sets to represent incomplete information. We generalize these two approaches, proposing generalized sets, and consider a relational model which combines all three types of set — collective, disjunctive and generalized. Finally, we present a further generalization of the above approaches and introduce a relational model with restricted cardinality set. In this model, we explicitly store the minimum and maximum number of actual values in each set. This results in a model which is more simple, flexible, and enhances the richness of information that can be represented
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A reinforcement learning based hybrid evolutionary algorithm for ship stability design
No full textOver the past decades, various search and optimisation methods have been used for ship design – a dynamic and complicated process. While several advantages of using these methods have been demonstrated, one of the main limiting factors of optimisation applications in ship design is the high runtime requirement of the involved simulations. This severely restricts the number of real applications in this area. This chapter presents a hybrid evolutionary algorithm that uses reinforcement learning to guide the search. Through giving and correcting the search direction, the runtime of optimisation can be effectively reduced. The NSGA-II, a well known multi-objective evolutionary algorithm, is utilised together with reinforcement learning to form the hybrid approach. As an important optimisation application field, the ship stability design problem has been selected for evaluating the performance of this new method. A Ropax (roll on/roll off passenger ship) damage stability problem is selected as a case study to demonstrate the effectiveness of the proposed approach
Coevolving a computer player for resource allocation games : using the game of Tempo as a test space.
Full text linkDecision-making in resource allocation can be a complex and daunting task. Often there exist circumstances where there is no clear optimal path to choose, and instead the decision maker must predict future need and allocate accordingly. The application of resource allocation can be seen in many organizations, from military, to high end commercial and political, and even individuals living their daily life. We define resource allocation as follows: the allocation of owner’s assets to further the particular cause of the owner.
We propose two ways that computers can assist with the task of resource allocation. Firstly they can provide decision support mechanisms, with alternate strategies for the allocations that might not have been previously considered. Secondly, they can provide training mechanisms to challenge human decision makers in learning better resource allocation strategies. In this research we focus on the latter, and provide the following general hypothesis: Coevolutionary algorithms are an effective mechanism for the creation of a computer player for strategic decision-making games.
To address this hypothesis, we present a system that uses coevolution to learn new strategies for the resource allocation game of TEMPO. The game of TEMPO provides a perfect test bed for this research, as it abstracts real-world military resource allocation, and was developed for training Department of Defence personnel. The environment created allows players to practice their strategic decision-making skills, providing an opportunity to analyse and improve their technique. To be truly effective in this task, the computer player the human plays against must be continuously challenging, so the human can steadily improve. In our research the computer player is represented as a fuzzy logic rule base, which allows us investigation into the strategies being created. This provides insight into the ways the coevolution addresses strategic decision-making.
Importantly, TEMPO also gives us an abstraction of another component of strategic decision-making that is not directly available in other games – that of intelligence (INTEL) and counter intelligence (CI). When resource allocation is occurring in a competitive circumstance, it is often beneficial to gain insight into what your opponent is doing through intelligence. In turn, an opponent may seek to halt or skew the information being gained. The use of INTEL and CI in TEMPO allows research into the effects this has on the resource allocation process and the coevolved computer player.
The development of a computer player for the game of TEMPO gives us endless possibilities of research. In this research, we have focused on the creation a computer player that can provide a fun and challenging environment for humans learning resource allocation strategies. We investigate the addition of memory to a coevolutionary algorithm for strategy creation. This includes mechanisms to select memory individuals for evaluation of coevolutionary individuals. We describe a successful strategy of selection, based on the way a human’s short and long term memory works. We then investigate the use of INTEL and CI in the game of TEMPO, and the way it is used by the coevolved computer players. Through this work, we present a new version of the TEMPO game that more realistically represents INTEL and CI. Finally, we describe a process that uses coevolution to adapt to a human player real-time, to create a tailored game-play experience. This process was tested in a user study, and showed a distinct advantage through the adaptive mechanism. Overall, we have made some important discoveries, and described some limitations that leave future research open. Ultimately, we have shown that our hypothesis is an achievable goal, with an exciting future.Thesis (Ph.D.) - University of Adelaide, School of Computer Science, 200
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
