Strategies for Evolving Diverse and Effective Behaviours in Pursuit Domains

Evolutionary algorithms have a tendency to overuse and exploit particular behaviours in their search for optimality, even across separate runs. The resulting set of monotonous solutions caused by this tendency is a problem in many applications. This research explores different strategies designed to encourage an interesting set of diverse behaviours while still maintaining an appreciable level of efficacy. Embodied agents are situated within an open plane and play against each other in various pursuit game scenarios. The pursuit games consist of a single predator agent and twenty prey agents, with the goal always requiring the predator to catch as many prey as possible before the time limit is reached. The predator's controller is evolved through genetic programming while the preys' controllers are hand-crafted. The fitness of a solution is first calculated in a traditional manner. Inspired by Lehman and Stanley's novelty search strategy, the fitness is then combined with the diversity of the solution to produce the final fitness score. The original fitness score is determined by the number of captured prey, and the diversity score is determined through the combination of four behaviour measurements. Among many promising results, a particular diversity-based evaluation strategy and weighting combination was found to provide solutions that exhibit an excellent balance between diversity and efficacy. The results were analyzed quantitatively and qualitatively, showing the emergence of diverse and effective behaviours

Consumo e gênero: uma revisão da produção historiográfica recente sobre a América Latina no século XX

A partir de una revisión de la producción historiográfica reciente que estudia el siglo XX, este artículo muestra la relevancia del género para la construcción de una historia del consumo en América Latina. Con este objetivo, se enfoca el análisis en tres líneas de investigación que, desde una aproximación interseccional, aportan nuevas miradas y preguntas: la primera destaca la dimensión política del consumo, centrándose en la relación entre género y clase; la segunda aborda consumo y trabajo doméstico, señalando el vínculo entre género y nación; y la tercera analiza cultura material y corporalidades, destacando la articulación entre género y edad.Starting from a recent historiographical production’s revision studying the 20th Century, this article depicts the relevance of gender for the history of consumption-building in Latin America. Bearing that in mind, the analysis is geared to three researching lines, contributing with new perspectives and questions, as from an inter sectorial approach: the first one highlights the political dimension of consumption based upon the interaction between gender and class; the second addresses consumption and domestic work, displaying a link between gender and nation, and the third one analyses material culture and corporality emphasizing upon the articulation between gender and age.A partir de uma revisão da produção historiográfica recente que estuda o século XX, este artigo mostra a relevância do gênero para a construção de uma história do consumo na América Latina. Com esse objetivo, a análise está focada em três linhas de pesquisa que, sob uma aproximação interseccional, contribuem com novos olhares e perguntas: a primeira destaca a dimensão política do consumo e foca-se na relação gênero e classe; a segunda aborda consumo e trabalho doméstico, e sinaliza o vínculo entre gênero e nação; a terceira analisa cultura material e corporalidade, e destaca a articulação entre gênero e idade.Fil: Pérez, Inés. Universidad Nacional de Mar del Plata. Facultad de Humanidades. Departamento de Sociologia; Argentina. Universidad Nacional de Mar del Plata. Facultad de Humanidades. Departamento de Historia. Centro de Estudios Históricos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentin

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Towards a Fully Integrated Accelerator on a Chip: Dielectric Laser Acceleration (DLA) From the Source to Relativistic Electrons

Dielectric laser acceleration of electrons has recently been demonstrated with significantly higher accelerating gradients than other structure-based linear accelerators. Towards the development of an integrated 1 MeV electron accelerator based on dielectric laser accelerator technologies, development in several relevant technologies is needed. In this work, recent developments on electron sources, bunching, accelerating, focussing, deflecting and laser coupling structures are reported. With an eye to the near future, components required for a 1 MeV kinetic energy tabletop accelerator producing sub-femtosecond electron bunches are outlined