Architectural design digital change: interactivity policy

Several researches have been focused on digital architecture historical perspectives of the design throughout the sixties. This paper purposes a different view based on the influence of art, science and computation in architecture that contributed to the use of interactivity in architectural design. The aim is to describe the evolution of interactive CAD from MIT’s Project CAD and Ivan Sutherland’s Sketchpad to the early digital architectural design pioneers: Steven Coons, Gyorgy Kepes and Nicholas Negroponte.info:eu-repo/semantics/publishedVersio

Análise evolutiva da produção de coco no estado de sergipe frente ao crescimento da cultura no Nordeste e no Brasil.

O cultivo do coqueiro é realizado em vários países, sendo que no Brasil é considerada uma frutífera de grande importância econômica e social em virtude da ampla variabilidade de produtos que podem ser obtidos com a sua exploração, além de desempenhar papel ecológico em ambientes fragilizados. Nos últimos anos no Brasil o cultivo de coco vem desencadeando transformações em termos econômicos e produtivos promovendo um novo arranjo geo-produtivo. O objetivo deste trabalho é contextualizar a evolução da cultura do coco no estado de Sergipe frente aos cenários produtivos da região Nordestina e Brasileira. A metodologia utilizada foi embasada na estatística descritiva como método de sintetizar uma série de valores, de 1990 a 2009, obtido através de órgão oficial brasileiro. No Brasil as maiores plantações e produções de coco se concentram na região do Nordeste. A cocoicultura no estado de Sergipe representa importante fonte de renda para muitos produtores, ocupando aproximadamente 42.000 mil ha, dos quais 80% estão localizados em área de baixada litorânea e tabuleiros costeiros. Atualmente é o estado com a segunda maior produção de coco no país e o terceiro em área plantada, destinado principalmente a produção de coco seco. Embora nos últimos anos haja uma redução de participação do estado de Sergipe em termos de área plantada com a fruta, observa-se que a contribuição do estado para a produção nordestina e brasileira aumentou substancialmente, graças ao incremento em produtividade. Fato este que demonstra a evolução tecnológica nos últimos 20 anos com a cultura do coqueiro. Mesmo assim o cenário geoeconômico e político do estado de Sergipe demonstram caráter de preocupação frente as transformações que se evidenciam, como expansão do cultivo de coco à outras regiões e, possivelmente na maior importação de coco beneficiado de outros países, que culminam no aumento de competitividade do setor

A dynamic method for charging-up calculations: the case of GEM

The simulation of Micro Pattern Gaseous Detectors (MPGDs) signal response is an important and powerful tool for the design and optimization of such detectors. However, several attempts to simulate exactly the effective charge gain have not been completely successful. Namely, the gain stability over time has not been fully understood. Charging-up of the insulator surfaces have been pointed as one of the responsible for the difference between experimental and Monte Carlo results. This work describes two iterative methods to simulate the charging-up in one MPGD device, the Gas Electron Multiplier (GEM). The first method uses a constant step for avalanches time evolution, very detailed, but slower to compute. The second method uses a dynamic step that improves the computing time. Good agreement between both methods was reached. Despite of comparison with experimental results shows that charging-up plays an important role in detectors operation, should not be the only responsible for the difference between simulated and measured effective gain, but explains the time evolution in the effective gain.Comment: Minor changes in grammatical statements and inclusion of some important information about experimental setup at section "Comparison with experimental results

Pressure effect in the X-ray intrinsic position resolution in noble gases and mixtures

A study of the gas pressure effect in the position resolution of an interacting X- or gamma-ray photon in a gas medium is performed. The intrinsic position resolution for pure noble gases (Argon and Xenon) and their mixtures with CO2 and CH4 were calculated for several gas pressures (1-10bar) and for photon energies between 5.4 and 60.0 keV, being possible to establish a linear match between the intrinsic position resolution and the inverse of the gas pressure in that energy range. In order to evaluate the quality of the method here described, a comparison between the available experimental data and the calculated one in this work, is done and discussed. In the majority of the cases, a strong agreement is observed

Geomechanical parameters updating in an underground work

In geotechnical engineering, and in the particular case of underground works, a great number of uncertainties arise due to the lack of knowledge of the involved formations and their variability. Geomechanical parameters are one of the main issues in the underground works design. In the initial stages, the available information about the rock masses characteristics is scarce. As the project advances to other stages more and more information from different sources becomes available and can be used for updating the geomechanical model. Bayesian methodologies use probability as the main tool to deal with uncertainty and manage to reduce it using new data via the Bayes theorem. In this work, a part of a developed Bayesian framework to the updating of the deformability modulus (E) in an underground structure is presented. Assuming E as a random variable, data from LFJ tests is used to obtain a posterior and less uncertain distribution of E. This approach led to good results and considerable uncertainty reduction and increased reliability. The developed Bayesian framework constitutes a rational and structured way of dealing with data with different sources and uncertainty levels.Fundação para a Ciência e a Tecnologia (FCT) - projecto POCI/ECM/57495/2004 entitled “Geotechnical Risk inTunnels for High Speed Trains”

Determination of geomechanical parameters using a KBS system and application to an underground station

In this paper a KBS computational system, designated by GEOPAT, for the calculation of geomechanical parameters for modelling underground structures in rock and soil formations is presented. To congregate the specialists' knowledge in rock and soil domains, and in particular in the tunnel engineering, causal nets have been established for decision support. GEOPAT determines the parameters for rock and soil formations, as well as heterogeneous rock formations. The developed GEOPAT system was applied to a large underground station in urban environment, excavated in granite formations, in order to obtain the deformability and strength parameters of the surrounding rock masses. Numerical models were developed considering either the obtained geomechanical parameters using artificial intelligence techniques or the parameters used in design. The numerical results obtained with the two sets of parameters are compared, as well as with the monitoring results. Some conclusions are drawn

Determinação de parâmetros geomecânicos em formações rochosas e maciços heterogéneos

Neste trabalho apresentam-se metodologias desenvolvidas para a obtenção de parâmetros geomecânicos em formações rochosas, incluindo-se a situação de maciços heterogéneos. No caso das formações rochosas, a quantificação desses parâmetros é analisada com base nos principais ensaios in situ e de laboratório e com recurso aos sistemas empíricos, com destaque para os sistemas RMR (Rock Mass Rating), Q e GSI (Geological Strength Index). No que se refere aos maciços rochosos claramente heterogéneos como acontece nas formações graníticas da região do Porto, faz-se uma referência às possíveis abordagens do problema, identificando-se, contudo, ainda a necessidade de investigação neste domínio

Simulation of gain stability of THGEM gas-avalanche particle detectors

Charging-up processes affecting gain stability in Thick Gas Electron Multipliers (THGEM) were studied with a dedicated simulation toolkit. Integrated with Garfield++, it provides an effective platform for systematic phenomenological studies of charging-up processes in MPGD detectors. We describe the simulation tool and the fine-tuning of the step-size required for the algorithm convergence, in relation to physical parameters. Simulation results of gain stability over time in THGEM detectors are presented, exploring the role of electrode-thickness and applied voltage on its evolution. The results show that the total amount of irradiated charge through electrode's hole needed for reaching gain stabilization is in the range of tens to hundreds of pC, depending on the detector geometry and operational voltage. These results are in agreement with experimental observations presented previously

Use of aI techniques and updating in geomechanical characterisation

Fundação para a Ciência e a Tecnologia (FCT) - projecto POCI/ECM/57495/2004 "Geotechnical Risk in Tunnels for High Speed Trains