Cismaşiu, C. The hybrid-{T}refftz Displacement Element for Static and Dynamic Structural Analysis Problems. Lisboa, Portugal: Instituto Superior Técnico, 2000.
AbstractThe displacement model of the hybrid-{T}refftz finite element formulation is applied to the solution of geometrically and physically linear static and dynamic problems. As the approximation bases solve locally the governing system of differential equations, the errors in the approximation affect only the implementation of the boundary conditions. Potential and elastostatic problems are used to illustrate the enforcement of the boundary conditions and the convergence of the solutions in energy, stresses and displacements, under both p- and h-refinement sequences and their insensitivity to mesh distortion, incompressibility and positioning of the coordinate system of the approximation basis. Also illustrated is the use of elements with arbitrary geometry and the efficiency that can be reached by including in the bases the solutions associated with dominant local effects, in particular those associated with singular stress fields. An adaptive p-refinement algorithm that exploits the naturally hierarchical nature of the approximation bases is presented and assessed. The formulation is generalised for elastodynamic analysis in the frequency domain of both bounded and unbounded domains, which are modelled either with absorbing boundary conditions or with semi-infinite elements that satisfy the Sommerfeld condition. The performance of the formulation is illustrated with tests on the convergence of the solutions in energy, stresses and displacements and on their insensitivity to mesh distortion, wave length and position of the absorbing boundary, for a wide spectrum of forcing frequencies and under both p- and h-refinement sequences.
Moniz, António, Sara Casaca, Mário Bairrada, and Conceição Moreno I&D, inovação e fomento de emprego: ideias chave de uma relação[R&D, innovation and job creation: key-ideas of a relation]. University Library of Munich, Germany, 2000.
AbstractThe increasing degree of inter-dependency and integration of economy at a global scale motivated the globalization of scientific and technological knowledge from manufacturing, to the marketing and the strategic management of companies that act as protagonists of these processes. Globalization of markets is inter-connected with intensive incorporation of knowledge in economy. In this sense the continuous evolution of the manufacturing industry structure for an increased high intensity technology elements, namely information and communication technologies, implies that these industrial sub-sectors are conditioning the global performance of economy, the productivity gains and as a consequence the levels of economical and employment growth. This study on “R&D, Innovation and Employment Creation” for the Portuguese Observatory of Employment and Vocational Training (IEFP-MQE) is updating information on the articulation between Job creation, innovation, technology, and R&D. A diagnosis of the state of national S&T research and of processes of technological and organizational innovation was made, as well of the interfacing structures between the knowledge sector and the economical activities. Were made 12 case studies at companies with some innovation activities, interviews to unionists and to Professional associations, and public offices. Was made also a survey to a selected sample of technological infrastructures.
Dias, JM, CA Cunha, S. Teixeira, G. Almeida, C. Costa, J. Lampreia, JJG Moura, I. Moura, and MJ Romao. "
Crystallization and preliminary X-ray analysis of a membrane-bound nitrite reductase from Desulfovibrio desulfuricans ATCC 27774."
ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY. 56 (2000): 215-217.
Abstract{Nitrite reductase from the sulfate-reducing bacterium Desulfovibrio desulfuricans ATCC 27774 is a multihaem (type c) membrane-bound enzyme that catalyzes the dissimilatory conversion of nitrite to ammonia. Crystals of the oxidized form of this enzyme were obtained using PEG and CaCl2 as precipitants in the presence of 3-(decylmethylammonium)propane-1-sulfonate and belong to the space group P2(1)2(1)2(1), With unit-cell parameters a = 78.94