2,387 research outputs found
3D hydrodynamic model as a tool for more efficient port management and operations.
Ports have been attempting to increase their competitiveness by enhancing their productivity and operate in a more environmentally friendly way. The Port of Seville is located in the Guadalquivir River in the south of Spain and it is the unique Spanish inland port. The estuary has generated and is still generating conflicts of interests. The access channel to the port is being periodically dredged, the natural course has been anthropologically modified several times, original salt marshes have been transformed to grow rice and approximately one-fourth of the total surface of the estuary is now part of two protected areas, one of them is a UNESCO_MAB Biosphere Reserve. Despite its socio-economic and environmental significance there is a surprising lack of scientific and technical information about the environmental interactions between the port activities and the Guadalquivir estuary stakeholders.
A 3D hydrodynamic model has been developed to study the tidal regime, water circulation, temperature and salinity distributions, flooding areas and the sediment dynamics in the estuary. The model output has been validated with in situ current speed, direction, water elevation and also with temperature and salinity measurements. Good agreement between modeled and real measurements have been obtained. Our preliminary results show that the vessel traffic management could be improved by using the tidal elevations and currents calculated by the model in the whole estuary. The interactions among the port activities (mainly due of changes in the sediments dynamics), the watershed management and the saline intrusion evolution will be studied in detail.
3D Hydrodynamic Modelling provide spatially explicit information on the key variables governing the dynamics of estuarine areas. The numerical model is a powerful tool to effectively guide the management and operations of ports located in a complex socio-ecological systems.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
Affine convex body semigroups
In this paper we present a new kind of semigroups called convex body
semigroups which are generated by convex bodies of R^k. They generalize to
arbitrary dimension the concept of proportionally modular numerical semigroup
of [7]. Several properties of these semigroups are proven. Affine convex body
semigroups obtained from circles and polygons of R^2 are characterized. The
algorithms for computing minimal system of generators of these semigroups are
given. We provide the implementation of some of them
Theoretical and experimental study of the vibrational spectra of 1.5-dimethylcytosine
The Raman spectra of the solid 1,5-dimethylcytosine and the FTIR spectra at room and low temperatures respectively have been registered. Quantum mechanical calculations of energies, geometries and vibrational wavenumbers were carried out by using ab initio (HF) and Density Functional Theory (DFT/BLYP and B3LYP) methods with different basis sets. The best level of theory in order to reproduce the experimental wavenumbers is the BLYP method with the 6-31G* basis set. The theoretical calculations indicate the presence of four stable tautomers of 1,5-dimethylcytosine: amino-oxo; imino-oxo (a and b) and imino-hidroxy. Their geometries were optimised by using the BLYP/6-31G* method, being the amino-oxo tautomer the most stable, followed by the imino-oxo tautomer, while the imino-hidroxy one is the most unstable. The complete assignment of the observed bands in the vibrational spectra of the amino-oxo tautomer is proposed in this work. © 2007 Elsevier B.V. All rights reserved.Fil: BrandĂĄn, S.A.. Universidad Nacional de TucumĂĄn; ArgentinaFil: Benzal, MarĂa Graciela. Universidad Nacional de TucumĂĄn; ArgentinaFil: GarcĂa Ramos, J.V.. Csic - Instituto de Estructura de la Materia (iem);Fil: Otero, J.C.. Universidad de MĂĄlaga; EspañaFil: Ben Altabef, Aida. Universidad Nacional de TucumĂĄn; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - TucumĂĄn. Instituto de QuĂmica del Noroeste. Universidad Nacional de TucumĂĄn. Facultad de BioquĂmica, QuĂmica y Farmacia. Instituto de QuĂmica del Noroeste; Argentin
Sustainable forest management of miombo woodlands in Niassa National Reserve, northern Mozambique: a multidisciplinary approach of fire resistance analysis.
Poster presented at XIII World Forestry Congress. Buenos Aires (Argentina). 18 - 23 Oct 2009
Forward and Inverse Dynamics and Quasi-Static Analysis of Mechanizes with MATLABÂź
There are many potential advantages of direct and inverse dynamic and quasi-static analysis of mechanisms, namely control the risk of slippage, improve stability, better adaptation to the environment, obtaining smooth movements and optimizing energy consumption. This chapter proposes new analysis methods and algorithms to bring new solutions to the mechanics of the machines under consideration. The methodology has been developed in modular programs thanks to the flexibility of MATLABÂź
Climatic and tectonic controls on carbonate deposition in syn-rift siliciclastic fluvial systems: A case of microbialites and associated facies in the Late Jurassic
This work provides new insights to assess the factors controlling carbonate deposition in the siliciclastic fluvial systems of rift basins. Sedimentological and stable-isotope data of microbialites and associated carbonate facies, along with regional geological information, are shown to reveal the influence of climate and tectonics on the occurrence and attributes of carbonate deposits in these settings. The Vega Formation â a 150 m thick Lower Kimmeridgian siliciclastic fluvial sequence in Asturias Province (northern Spain) â constitutes a candidate for this approach. This unit includes varied facies (stromatolites; rudstones, packstones and wackestones containing oncoids, intraclasts, charophytes and shell bioclasts; marlstones and polygenic calcareous conglomerates) that formed in a low-gradient fluvialâlacustrine system consisting of shallow, low-sinuosity oncoid-bearing channels and pools within marshy areas, with sporadic coarse alluvial deposition. The sedimentological attributes indicate common erosion by channel overflow and rapid lateral changes of subenvironments caused by water-discharge variations. The carbonate fluvialâlacustrine system developed near uplifted marine Jurassic rocks. The occurrence of the system was conditioned by normal faults (active during the deposition of the unit) that favoured: (i) springs of HCO3âCa-rich water from a RhaetianâSinemurian carbonate rock aquifer; and (ii) carbonate deposition in areas partially isolated from the adjacent siliciclastic fluvial system. The microbialite d13C and d18O values support deposition in a hydrologically open system, fed by ambient-temperature meteoric water, with riparian vegetation. Three types of lamination in the stromatolites and oncoids reflect distinct morphological types of cyanobacterial communities. The textural pattern of lamination parallels d13C and d18O changes, suggesting short-term cycles of precipitation and temperature. A moderately to strongly contrasted seasonal and/or pluriannual precipitation regime is inferred from the cyclic d13C pattern of the lamination and from the discontinuous and asymmetrical growth of oncoids. Thus, the isotopic and sedimentological attributes of the carbonate deposits were linked to short-term climate changes associated with semi-arid conditions, consistent with the studied climatic zone
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