67 research outputs found

    The Use of Data and Models for Assessing the Equilibrium Partitioning Approach for Analysising Environmental Quality Standards in the Water Column and in the Sediments

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    An analysis of experimental and simulated data has been performed to study the relationships between EQS defined for surface waters in the Daughter Directive (COM (2006) 397) and possible EQS defined for sediments. From the above analysis of experimental and simulated data, it is clear that even though there is a coupling between water column and sediments, it is not possible to assess the chemical quality status of sediments based on water column data and viceversa. At the moment EQS have been defined for the water column and therefore these EQS will assess only the compliance with good chemical status of surface waters. If EQS were to be defined for sediments, these EQS will not reflect systematically the surface water quality and therefore they could not be used for this purpose, being the contrary is also true, i.e. compliance with EQS values for water column does not reflect sediment chemical status. However, it is clear that the good chemical quality of a water body will depend on having good chemical quality of surface water and sediments and that to assess both it is necessary to measure in both media. The same EQS developed for water could, in principle, be applied to porewater, hence, there is no need of developing another set of EQS. If porewater could not be measured, then the partitioning approach to pass to sediment concentrations should be applied. However, in this case an additional uncertainty is added to the procedure and therefore it is necessary to develop to develop new techniques and better databases since at the moment the predictions are between several orders of magnitude, which are not adequate for setting EQS. Additionally, the use of this approach would certainly require the characterization of the sediments in terms of its physical (grain size, material, temperature), chemical (organic matter content, black carbon, pH, redox, etc.) and biological (e.g. bioturbation), which at the moment are not obtained from standard environmental monitoring.JRC.H.5-Rural, water and ecosystem resource

    Comparison of Monitoring Approaches for Selected Priority Pollutants in Surface Water - An Initiative in support to the Water Framework Directive Chemical Monitoring Activity

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    Laboratories from seven EU Member States under the coordination of the Joint Research Centre and in collaboration with the Provincia di Ferrara participated in a technical on-site project during which sampling and analytical methodologies for chemical monitoring according to proposed WFD provisions have been compared. Laboratories had been invited to take samples from a river according to their standard protocols and to analyse them for PAHs, PBDE and Nonyl-, Octylphenol. It was shown that it is possible to analyse contaminants at relevant levels. Results showed also that currently only experienced laboratories can achieve the required performance, indicating the need for improvement at European level.JRC.H.5-Rural, water and ecosystem resource

    Realidades interculturales, miradas hacia el género y la educación

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    Este texto contribuye al análisis científico de varias áreas del conocimiento como la filosofía social, la patología, la educación para el cuidado del medio ambiente y la sustentabilidad que inciden en diversas unidades de aprendizaje de la Licenciatura en Educación para la Salud y de la Maestría en Sociología de la SaludLa presente obra, es la reunión de varias investigaciones que se han dado cita para construir un libro que representa el horizonte de autores y lectores en la pasión del dialogo. Se trata de experiencias de los observadores e interpretes de la realidad de los observadores e interpretes de la realidad social quienes se aventuraron a reunir las voces de los informantes que resguardan los secretos de sus comunidades acerca de su cultura, organización simbólica, y de sus practicas y rituales engarzados en la vida cotidiana

    El filtraje aplicado al seguimiento visual de objetos

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    El filtro de Kalman ha sido usado exitosamente en diferentes aplicaciones de predicción o determinación del estado de un sistema. Un campo importante en la visión por computadora es el seguimiento de objetos. Diferentes tipos de movimiento así como el ocultamiento de objetos a seguir pueden obstaculizar la labor de seguimiento. En este trabajo, se presenta el uso del filtro de Kalman para el seguimiento de objetos. Además se considera tanto la capacidad del filtro para tolerar pequeños ocultamientos del objeto así como el uso del filtro de Kalman extendido para el modelaje de movimientos complejos

    Modelling the Influence of Thermal Stratification and Complete Mixing on the Distribution and Fluxes of Polychlorinated Biphenyls in the Water Column of Ispra Bay (Lake Maggiore)

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    A 1D coupled hydrodynamic and contaminant fate model was applied to simulate the distribution of polychlorinated biphenyls (PCBs) in the Ispra Bay located in the southern part of Lake Maggiore (Italy). The model succeeded in representing the hydrodynamic processes occurring in the lake such as thermal stratification during summer 2005 followed by the complete mixing of the water column in February 2006. The results of the PCB fate model highlighted that these processes play a key role for the settling of particles and consequently for the distribution of PCBs in the water column as well as for the contaminant flux at the sediment¿water interface. On the air¿water front, the simulations emphasised that the net atmospheric PCB input fluxes are generally more important during the cold season and show peaks during periods of high wet deposition. Finally, the seasonal variability of the distribution of PCB in the water column was assessed.JRC.H.1-Water Resource

    On the Use of the Partitioning Approach to Derive Environmental Quality Standards (EQS) for Persistent Organic Pollutants (POPs) in Sediments: A Review of Existing Data

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    A review of experimental data has been performed to study the relationships between EQS defined for surface waters in the Daughter Directive (COM (2006) 397) and possible EQS defined for sediments. The analysis of experimental data showed that even though in some specific cases there is a coupling between water column and sediments, this coupling is rather the exception. Therefore it is not recommendable to use water column data to assess the chemical quality status of sediments. At the moment EQS have been defined for the water column and therefore these EQS will assess only the compliance with good chemical status of surface waters. It is clear that the good chemical quality of a water body will depend on having good chemical quality of surface water and sediments and that to assess both it is necessary to measure in both media. The EQS developed for water could be applied to pore water (interstitial water); hence, there would be no need of developing another set of EQS. However, the measurement of pore water concentrations faces several technical problems. Therefore, the partitioning approach has been proposed as a solution to calculate sediment EQS from water EQS. Unfortunately, in this case an uncertainty between 2-3 orders of magnitude is added to the procedure and this is not adequate for setting sediment EQS. It is expected that analytical developments will improve the actual situation.JRC.H.5-Rural, water and ecosystem resource

    Alternative way to compute the euler number of a binary image

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    In this paper an alternative way to compute the (E) Euler number of a binary image via information about its pixels is presented. The P perimeter of the objects in the image, their P c contact perimeter and the T-type pixel are used to obtain this important invariant. This is the second time the Euler number is described in terms of the contact perimeter of the objects in an image but with new results. The first paper that reports computing the Euler number of a binary shape in terms of the P and P c is in [E. Bribiesca, Computation of the Euler number using the contact perimeter, Computers and Mathematics with Applications 60:1364-137 (2010)]. Bribiesca's proposal is useful only for unit-width shapes. In this paper, we extend Bribiesca's method for non-unit-width shapes
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