Observations of ammonia in galacticHii regions     

J. W. S. Vilas Boas  E. Scalise Jr.  J. L. Monteiro Do Vale 《Astrophysics and Space Science》1988,141(2):339-346

The ammonia emission associated with southern galacticHii regions have been studied. Some physical parameters, computed for each individual sources, were derived and a brief discussion follows.  相似文献   

An Algebra for Spatiotemporal Data: From Observations to Events     

Karine Reis Ferreira  Gilberto Camara  Antônio Miguel Vieira Monteiro 《Transactions in GIS》2014,18(2):253-269

Recent technological advances in geospatial data gathering have created massive data sets with better spatial and temporal resolution than ever before. These large spatiotemporal data sets have motivated a challenge for Geoinformatics: how to model changes and design good quality software. Many existing spatiotemporal data models represent how objects and fields evolve over time. However, to properly capture changes, it is also necessary to describe events. As a contribution to this research, this article presents an algebra for spatiotemporal data. Algebras give formal specifications at a high‐level abstraction, independently of programming languages. This helps to develop reliable and expressive applications. Our algebra specifies three data types as generic abstractions built on real‐world observations: time series, trajectory and coverage. Based on these abstractions, it defines object and event types. The proposed data types and functions can model and capture changes in a large range of applications, including location‐based services, environmental monitoring, public health, and natural disasters.  相似文献   

Numerical modelling assessment of climate-change impacts and mitigation measures on the Querença-Silves coastal aquifer (Algarve,Portugal)     

Rui Hugman  Tibor Stigter  Luis Costa  José Paulo Monteiro 《Hydrogeology Journal》2017,25(7):2105-2121

Predicted changes in climate will lead to seawater intrusion in the Querença-Silves (QS) coastal aquifer (south Portugal) during the coming century if the current water-resource-management strategy is maintained. As for much of the Mediterranean, average rainfall is predicted to decrease along with increasing seasonal and inter-annual variability and there is a need to understand how these changes will affect the sustainable use of groundwater resources. A density-coupled flow and transport model of the QS was used to simulate an ensemble of climate, water-use and adaptation scenarios from 2010 to 2099 taking into account intra- and inter-annual variability in recharge and groundwater use. By considering several climate models, bias correction and recharge calculation methods, a degree of uncertainty was included. Changes in rainfall regimes will have an immediate effect on groundwater discharge; however, the effect on saltwater intrusion is attenuated by the freshwater–saltwater interfaces’ comparatively slow rate of movement. Comparing the effects of adaptation measures demonstrates that the extent of intrusion in the QS is controlled by the long-term water budget, as the effectiveness of both demand and supply oriented measures is proportional to the change in water budget, and that to maintain the current position, average groundwater discharge should be in the order of 50 × 10⁶ m³ yr^?1.  相似文献   

Effect of tooth spacing and mesh size on the catch of the Portuguese clam and razor clam dredge   总被引：1，自引：1，他引：0  

Gaspar  M. B.; Castro  M.; Monteiro  C. C. 《ICES Journal of Marine Science》1999,56(1):103-110

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Probabilistic models for structures with bilinear demand-intensity relationships     

Gerard J. O'Reilly  Ricardo Monteiro 《地震工程与结构动力学》2019,48(2):253-268

An extension to the existing SAC/FEMA expressions to estimate mean annual frequency of exceedance (MAFE) for a given limit state is described. In specific, this study pertains to structural systems whose demand versus seismic intensity relationship cannot be reasonably represented by a linear fit in logspace, but rather a bilinear fit over the entire range of structural response. Using a predefined limiting intensity, the median demand is separated into two distinct zones of response. These expressions are derived using a second-order polynomial hazard model fit and can be considered a further extension of the closed-form expressions available in the literature. The steps in the derivation are described along with an example application of the proposed expressions. Comparing different models shows that the MAFE can be significantly misrepresented when using a linear demand-intensity model for systems whose behaviour deviates from this assumption in logspace. Similarly, a logarithmic function demand-intensity fit is examined and seen not to be suitable in the specific situations focused on here. Furthermore, significant underestimation or overestimation is observed when using local fits in the vicinity of the behaviour transition point, which highlights the need for such a bilinear model when assessing the structural performance at the transition point's vicinity. Adopting a bilinear model is shown to better represent structural systems with complex response characteristics, also allowing the use of a single demand model for the entire range of response. This is at the same time still compatible with the existing framework for performance-based seismic design and assessment.  相似文献   

Presence of Anthropogenic Markers in Water: A Case Study of the Guaporé River Watershed,Brazil          下载免费PDF全文

Marilia Camotti Bastos  Danilo Rheinheimer dos Santos  José A. Monteiro de Castro Lima  Thibaut le Guet  Maria A. Santanna dos Santos  Renato Zanella  Elodie Aubertheau  Leslie Mondamert  Laurent Caner  Jérôme Labanowski 《洁净——土壤、空气、水》2018,46(3)

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