A integração Google Earth-SIG-Servidor de mapas e o monitoramento ambiental.

bitstream/item/79549/1/circ-183.pd

Avaliação da absorção de água e viabilidade de três genótipos de sementes de Jatropha curcas L.

Edição dos resumos do 18º Congresso Brasileiro de Sementes, 2013, Florianópolis. CD-ROM

Caracterização das potencialidades germinativas de três genótipos de sementes de Jatropha curcas L.

Edição dos resumos do 18º Congresso Brasileiro de Sementes, 2013, Florianópolis. CD-ROM

Studies on on-line state and parameter estimation through a real-time process simulator

A PC-based simulator of non-linear multiple-input multiple-output dynamic systems was employed for studies concerning the on-line estimation of both 'non-measured' state variables and multiple specific growth rates of a virtual baker´s yeast fed-batch fermentation. The identification algorithms were implemented in an 'Observer Computer' which received, optionally in 'real-time', in 'scaled time' or in 'simulation time', the 'measured' state variables generated by the process simulator in the 'Process Computer'. The state observer showed a robust behaviour under different situations where process parameters, operating variables and measuring characteristics (noise and delays) were changed in the process computer. The simulation package was seen to be an efficient and cheap tool for the simulation of non-linear processes with time varying parameters, providing a realistic environment for tests of identification, estimation and control strategies.Junta Nacional de Investigação Científica e Tecnológica (JNICT) - BD/224/90-IF, BD/1476/91-RM.Instituto Nacional de Investigação Científica (INIC)

Model-based identification and control on baker's yeast fed-batch fermentation

A theoretical and experimental study is reported concerning the control of baker's yeast fed-batch fermentation. The overall approach follows the methodology proposed by Bastin & Dochain (1990) which exploits the structure of a general nonlinear deterministic model for bioreactors. Software-sensors have been developed and employed for the on-line estimation of 'non-measured' state variables (Feyo de Azevedo et al., 1992). An adaptive linearizing control cheme, based as well on the general model structure, utilises the observed state to compute the control action. The strategy was tested theoretically through a 'real-time process simulator' (Pimenta & Feyo de Azevedo, 1993) acting as the baker's yeast fermentation, linked to a 'control computer' via serial RS232C communications. Experimental work was carried out in parallel in a 5 litre laboratory rig (B. Braun Biostat MD5) locally controlled by a 'digital control unit' and supervised by a control computer. The main results to be reported address the overall performance of the control scheme, particularly in what concerns its sensitivity to model uncertainty, the noises in measurements and to slow and fast changing process parameters. As well it is relevant to emphasise that the 'process simulator' employed has proved to be an important tool for studies on process control and for experiment planning

Computer-based studies on bioprocess engineering : II - Tools for process operation

In this paper we review recent advances on the practice and theory of process control with particular emphasis to the operation of bioreactors. We present in detail a case-study on the modelling, model-based identification and adaptive control of fed-batch baker's yeast fermentation.Junta Nacional de Investigação Científica e Tecnológica (JNICT) - contract numbers BD/224/90-IF, BD/1476/91-RM.Instituto Nacional de Investigação Científica (INIC)

Programação de servidor de mapas para disponibilização de dados geográficos multidisciplinares utilizando tecnologias livres.

A crescente utilização de geotecnologias, e consequente elaboração de bases cartográficas, vem demandando a implementação de ferramentas para acesso dinâmico e interativo às informações organizadas. Servidores de mapas possibilitam a integração de informações geográficas representadas por mapas temáticos, imagens de satélite, fotografias aéreas ortorretificadas, e modelos 3D ou de realidade virtual georreferenciados. Nesse contexto, o presente trabalho apresenta procedimentos adotados para a programação do servidor de mapas desenvolvido para facilitar o acesso a informações georreferenciadas disponibilizadas no GeoPortal da Embrapa Milho e Sorgo. O servidor de mapas permite o acesso a bases cartográficas digitais na internet de forma interativa e dinâmica, utilizando software livres, considerando as plataformas Windows e Linux e possibilitando a integração espacial de informações geográficas multidisciplinares provenientes de diferentes fontes e formatos.bitstream/item/95877/1/doc-158.pd

Edge phonons in black phosphorus

Exfoliated black phosphorus has recently emerged as a new two-dimensional crystal that, due to its peculiar and anisotropic crystalline and electronic band structures, may have potentially important applications in electronics, optoelectronics and photonics. Despite the fact that the edges of layered crystals host a range of singular properties whose characterization and exploitation are of utmost importance for device development, the edges of black phosphorus remain poorly characterized. In this work, the atomic structure and the behavior of phonons near different black phosphorus edges are experimentally and theoretically studied using Raman spectroscopy and density functional theory calculations. Polarized Raman results show the appearance of new modes at the edges of the sample, and their spectra depend on the atomic structure of the edges (zigzag or armchair). Theoretical simulations confirm that the new modes are due to edge phonon states that are forbidden in the bulk, and originated from the lattice termination rearrangements.Comment: 15 pages, 4 figure

Probing the Electronic Structure of Bilayer Graphene by Raman Scattering

The electronic structure of bilayer graphene is investigated from a resonant Raman study using different laser excitation energies. The values of the parameters of the Slonczewski-Weiss-McClure model for graphite are measured experimentally and some of them differ significantly from those reported previously for graphite, specially that associated with the difference of the effective mass of electrons and holes. The splitting of the two TO phonon branches in bilayer graphene is also obtained from the experimental data. Our results have implications for bilayer graphene electronic devices.Comment: 4 pages, 4 figure