123 research outputs found

    Cognitive architectures as Lakatosian research programmes: two case studies

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    Cognitive architectures - task-general theories of the structure and function of the complete cognitive system - are sometimes argued to be more akin to frameworks or belief systems than scientific theories. The argument stems from the apparent non-falsifiability of existing cognitive architectures. Newell was aware of this criticism and argued that architectures should be viewed not as theories subject to Popperian falsification, but rather as Lakatosian research programs based on cumulative growth. Newell's argument is undermined because he failed to demonstrate that the development of Soar, his own candidate architecture, adhered to Lakatosian principles. This paper presents detailed case studies of the development of two cognitive architectures, Soar and ACT-R, from a Lakatosian perspective. It is demonstrated that both are broadly Lakatosian, but that in both cases there have been theoretical progressions that, according to Lakatosian criteria, are pseudo-scientific. Thus, Newell's defense of Soar as a scientific rather than pseudo-scientific theory is not supported in practice. The ACT series of architectures has fewer pseudo-scientific progressions than Soar, but it too is vulnerable to accusations of pseudo-science. From this analysis, it is argued that successive versions of theories of the human cognitive architecture must explicitly address five questions to maintain scientific credibility

    Efeito de fontes e doses de acidificantes no pH do solo coletado do piso de galinheiros

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    A acidificação de resíduo de animais vem sendo uma das maneiras de combater proliferação de bactérias e a alta volatilização de amônia (NH3). No Brazil, contrariamente, procede a alcalinização com óxidos básicos com elevação do pH da cama e solo do piso dos aviários, criando neste último uma fonte constante de contaminação. Neste sentido, este estudo teve como objetivo verificar o efeito de Bissulfato de sódio (SB) e enxofre elementar (ES) na acidificação de diferentes solos de aviário, quanto a eficiência e tempo de reação. Utilizou-se três solos coletados dentro de galpões de criação de frango (6, 36 e 60 meses de ocupação), além da coleta do solo externo ao aviário, totalizando quatro locais de amostragens. As duas fontes de acidificantes, o SB e o ES foram aplicadas em 6 doses crescentes (0, 2, 3, 6, 12 e 24 cmolc/kg de H+ na camada de 3 cm de solo), incubados até 53 dias. Ao final de cada período de incubação determinou-se o pH do solo. Os resultados do presente estudo permitiram concluir que o SB é eficiente na redução do pH do solo de aviário com reação imediata após sua aplicação. Nas condições do presente estudo a dose indicada de SB para reduzir o pH para 5,0 foi de 6 cmolc kg-1 H+ que correspondeu a aplicação de 7,2 g do produto em 500 g de solo. O ES elementar mostrou reação lenta e baixa eficiência. Acidificação do solo do aviário pode ser obtido rapidamente e eficientemente com uso de SB

    Observations of Toroidal Coupling for Low-N Alfven Modes in the Tca Tokamak

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    The antenna structure in the TCA tokamak is phased to excite preferentially Alfven waves with known toroidal and poloidal wave numbers. Surprisingly, the loading spectrum includes both discrete and continuum modes with poloidal wave numbers incompatible with the antenna phasing. These additional modes, which are important for our heating experiments, can be attributed to linear mode coupling induced by the toroidicity of the plasma column, when we take into account ion-cyclotron effects

    Adaptability, stability, productivity and genetic parameters in slash pine second-generation families in early age.

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    Made available in DSpace on 2017-11-29T23:22:24Z (GMT). No. of bitstreams: 1 2016ValderesSGAdaptability.pdf: 1280522 bytes, checksum: aac11aecc16c66ff96fa6a9035c99e71 (MD5) Previous issue date: 2017-11-29bitstream/item/167754/1/2016-Valderes-SG-Adaptability.pd
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