17,790 research outputs found
Tecnologia para biodegradação da casca de coco sem gerar outros resíduos.
bitstream/CPATC/19770/1/f_07_2007.pdfExiste o documento impresso
Tecnologia para biodegradação da casca de coco seco e de outros resíduos do coqueiro.
bitstream/item/158629/1/ct-46.pd
Metodologia para análise de rentabilidade e riscos de sistemas agroflorestais.
Este trabalho propõe uma metodologia para avaliação da rentabilidade e riscos de sistemas agroflorestais e de cada um dos seus componentes culturais, através da combinação da técnica Monte Carlo, comumente utilizada para avaliar riscos em investimentos, com um método de rateio dos custos comuns entre os componentes culturais, possibilitando a análise do sistema como um todo e a análise isolada de cada um desses componentes.bitstream/CPAF-AC/3989/1/doc47.pd
Emergence of Hierarchy on a Network of Complementary Agents
Complementarity is one of the main features underlying the interactions in
biological and biochemical systems. Inspired by those systems we propose a
model for the dynamical evolution of a system composed by agents that interact
due to their complementary attributes rather than their similarities. Each
agent is represented by a bit-string and has an activity associated to it; the
coupling among complementary peers depends on their activity. The connectivity
of the system changes in time respecting the constraint of complementarity. We
observe the formation of a network of active agents whose stability depends on
the rate at which activity diffuses in the system. The model exhibits a
non-equilibrium phase transition between the ordered phase, where a stable
network is generated, and a disordered phase characterized by the absence of
correlation among the agents. The ordered phase exhibits multi-modal
distributions of connectivity and activity, indicating a hierarchy of
interaction among different populations characterized by different degrees of
activity. This model may be used to study the hierarchy observed in social
organizations as well as in business and other networks.Comment: 13 pages, 4 figures, submitte
Immunization and Aging: a Learning Process in the Immune Network
The immune system can be thought as a complex network of different
interacting elements. A cellular automaton, defined in shape-space, was
recently shown to exhibit self-regulation and complex behavior and is,
therefore, a good candidate to model the immune system. Using this model to
simulate a real immune system we find good agreement with recent experiments on
mice. The model exhibits the experimentally observed refractory behavior of the
immune system under multiple antigen presentations as well as loss of its
plasticity caused by aging.Comment: 4 latex pages, 3 postscript figures attached. To be published in
Physical Review Letters (Tentatively scheduled for 5th Oct. issue
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