Estratégia da Produção e Flexibilidade.

Vem-se tornando cada vez mais usual denominar a época que atravessamos, como a era do pós-taylorismo, ou da flexibilidade. As actuais condições de mercado, com instabilidade, aumento de concorrência e exigências específicas dos clientes, colocaram em questão a organização do trabalho taylorista-fordista, recorrendo-se, de forma crescente, à automatização flexível. Longe vai o tempo em que a organização do trabalho, marcada pela divisão rígida de funções, fragmentação de tarefas, especialização de conhecimentos, hierarquização e centralização de informações, deu lugar a uma precária flexibilização, frequentemente reduzida a uma componente técnico-empresarial e a uma flexibilidade quantitativa dos recursos humanos como forma de superar os disfuncionamentos tayloristas

Charge-density waves in one-dimensional Hubbard superlattices

We study the formation of charge density waves (CDW's) in one-dimensional Hubbard superlattices, modeled by a repeated pattern of repulsive (U>0) and free (U=0) sites. By means of Lanczos diagonalizations for the ground state, we calculate the charge structure factor. Our results show that while the superlattice structure affects the modulation of the charge density waves, the periodicity can still be predicted through an effective density. We also show that, for a fixed repulsive layer thickness, the periodicity of the CDW is an oscillatory function of the free layer thickness.Comment: 4 pages, 4 figure

Limits of space-times in five dimensions and their relation to the Segre Types

A limiting diagram for the Segre classification in 5-dimensional space-times is obtained, extending a recent work on limits of the energy-momentum tensor in general relativity. Some of Geroch's results on limits of space-times in general relativity are also extended to the context of five-dimensional Kaluza-Klein space-times.Comment: Late

Análise do comportamento in vitro de explantes foliares de pequizeiro (Caryocar brasiliense camb.) através de RAPD.

xEdição de resumos do 7º Congresso Brasileiro de Fisiologia Vegetal, Brasília, 1999

Bifinite Chu Spaces

This paper studies colimits of sequences of finite Chu spaces and their ramifications. Besides generic Chu spaces, we consider extensional and biextensional variants. In the corresponding categories we first characterize the monics and then the existence (or the lack thereof) of the desired colimits. In each case, we provide a characterization of the finite objects in terms of monomorphisms/injections. Bifinite Chu spaces are then expressed with respect to the monics of generic Chu spaces, and universal, homogeneous Chu spaces are shown to exist in this category. Unanticipated results driving this development include the fact that while for generic Chu spaces monics consist of an injective first and a surjective second component, in the extensional and biextensional cases the surjectivity requirement can be dropped. Furthermore, the desired colimits are only guaranteed to exist in the extensional case. Finally, not all finite Chu spaces (considered set-theoretically) are finite objects in their categories. This study opens up opportunities for further investigations into recursively defined Chu spaces, as well as constructive models of linear logic