1,721,052 research outputs found
Awada (Hassan) Le Liban et le flux islamiste
No full textAwada (Hassan) Le Liban et le flux islamiste. In: Archives de sciences sociales des religions, n°67/2, 1989. p. 212
Awada (Hassan) Le Liban et le flux islamiste
No full textAwada (Hassan) Le Liban et le flux islamiste. In: Archives de sciences sociales des religions, n°67/2, 1989. p. 212
Forested Infiltration Areas as a Natural Solution for Nitrate Mitigation in Contaminated Water
No full textA Managed Aquifer Recharge (MAR) approach is being utilized through a Forested Infiltration Area (FIA) to mitigate nitrate contamination in an aquifer situated within a Nitrate Vulnerable Zone. This innovative technique is deployed at a pilot site where the groundwater nitrate contents is higher than the threshold of regulatory limits defined by the EU Directive 91/676/EEC. Drainage water, sourced from a nearby dewatering pumping station and containing an average nitrate concentration of 70 mg L−1, is channeled into the area. The infiltration process occurs through six recharge trenches, totaling 300 m in length and one meter in depth, filled with a mixture of eucalyptus wood chips (50% by volume), inert material, clay and iron oxides. This blend termed the “Passive Treatment System” (PTS), enhances the activity of denitrifying bacteria that transform nitrate (NO3−) into nitrogen gas (N2). The objective is to lower nitrate levels in the drainage water entering the trenches and subsequently use this treated water to recharge and dilute the polluted underlying aquifer. Hydrogeochemical monitoring results indicate a notable decrease in NO3− in the infiltrated water, demonstrating that the FIA method can be an effective Nature-Based Solution for the remediation of nitrate-contaminated water
Modelling soil moisture and daily actual evapotranspiration: Integrating remote sensing surface energy balance and 1D Richards equation
No full textEvapotranspiration (ET) is a crucial component of the soil - plant-atmosphere system. In semi -arid Mediterranean regions, most land water loss occurs through ET, encompassing both evaporation from the earth ' s surface and plant transpiration. A comprehensive understanding of the actual ET spatiotemporal dynamics is critically important for hydrological modelling and effective water resource management. This significance is further pronounced considering the growing stress on water resources and the potential influence of climate change on water fluxes. Remote sensing (RS) provides long-term, high-resolution data that can contribute to the monitoring and management of natural ecosystems. Surface energy balance (SEB) methods relying on satellite remote sensing have proven effective in measuring actual evapotranspiration (ET a eb ) across different scales. However, their applicability may be constrained by interruptions in image acquisition caused by cloud cover and/or the spatio-temporal resolution limitations of satellites. In this research, a model-based methodology is suggested for simulating the dynamics of the soil - plant-atmosphere system and for estimating the daily actual evapotranspiration (ET p act ) of a Mediterranean Maquis ecosystem in northwest Sardinia. The model integrates ET a eb estimates obtained from the SEBAL model utilizing Landsat-8 data, satellite-derived vegetation indices, on-site measurements of potential evapotranspiration, and the mono-dimensional transient flow Richards equation for simulating soil moisture within the root zone. By combining these elements, the proposed model provides a more comprehensive and accurate estimate of the ET p act between Landsat acquisitions. The SEBAL model showed satisfactory performance in estimating actual evapotranspiration (ET a eb ) on satellite acquisition days, with an average error of 17 % compared to Eddy Covariance measurements. In addition, the integrated modelling approach yielded an ET p act average estimation error of +/- 37 % in the whole studied period. The soil moisture simulation by the model had a notable accuracy with an average error of 7.1 %. Temporal analysis showed that the model effectively simulated ET p act and soil moisture under both dry and wet conditions, exhibiting similar monthly and daily variations as observed data. Furthermore, a sensitivity analysis revealed that the stress index significantly improved the model ' s accuracy, while vegetation dynamics had a lower impact. Overall, the proposed model is a valuable tool for estimating ET p act in semi -arid Mediterranean regions, providing important information for water resource management and conservation efforts. Further application and validation of the model are recommended as new data becomes accessible, especially in areas characterized by cropped and irrigated agriculture. In future work, we aim to spatialize the Richards equation and integrate a multidimensional water balance hydrologic model
Satellite-Based Machine Learning for Soil Moisture Prediction and Land Conservation Practice Assessment in West African Drylands
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Assessing the performance of a large-scale irrigation system by estimations of actual evapotranspiration obtained by Landsat satellite images resampled with cubic convolution
No full textRemote sensing techniques allow monitoring the Earth surface and acquiring worthwhile information that can be used efficiently in agro-hydrological systems. Satellite images associated to computational models represent reliable resources to estimate actual evapotranspiration fluxes, ET a , based on surface energy balance. The knowledge of ET a and its spatial distribution is crucial for a broad range of applications at different scales, from fields to large irrigation districts. In single plots and/or in irrigation districts, linking water volumes delivered to the plots with the estimations of remote sensed ET a can have a great potential to develop new cost-effective indicators of irrigation performance, as well as to increase water use efficiency. With the aim to assess the irrigation system performance and the opportunities to save irrigation water resources at the “SAT Llano Verde” district in Albacete, Castilla-La Mancha (Spain), the Surface Energy Balance Algorithm for Land (SEBAL) was applied on cloud-free Landsat 5 Thematic Mapper (TM) images, processed by cubic convolution resampling method, for three irrigation seasons (May to September 2006, 2007 and 2008). The model allowed quantifying instantaneous, daily, monthly and seasonal ET a over the irrigation district. The comparison between monthly irrigation volumes distributed by each hydrant and the corresponding spatially averaged ET a , obtained by assuming an overall efficiency of irrigation network equal to 85%, allowed the assessment of the irrigation system performance for the area served by each hydrant, as well as for the whole irrigation district. It was observed that in all the investigated years, irrigation volumes applied monthly by farmers resulted generally higher than the corresponding evapotranspiration fluxes retrieved by SEBAL, with the exception of May, in which abundant rainfall occurred. When considering the entire irrigation seasons, it was demonstrated that a considerable amount of water could have been saved in the district, respectively equal to 26.2, 28.0 and 16.4% of the total water consumption evaluated in the three years
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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