Search results for "Flood"
showing 10 items of 256 documents
Spatial variability of channel changes in a mediterranean ephemeral stream in the last six decades (1946-2006)
2014
An analysis of morphological changes during the last six decades is presented for the Rambla de Cervera, a Mediterranean ephemeral stream located in the eastern sector of the Iberian Mountain Range. The studied channel (16.5 km) has two contrasted sectors: a horst confined sector (5.5 km) and a graben sector (11 km). Channel changes were analysed through the analysis of aerial photographs, with geographical information systems (GIS) and comparison of topographic surveys made with a GPS-RTK. Between 1946 and 2006 the Rambla de Cervera, underwent channel adjustments comparable to those observed in other Mediterranean rivers. The gravel channel markedly narrowed, losing width (68.5%) and chann…
The impact of agricultural management on selected soil properties in citrus orchards in Eastern Spain: A comparison between conventional and organic …
2017
The agricultural management of citrus orchards is changing from flood irrigated managed orchards to drip irrigated organic managed orchards. Eastern Spain is the oldest and largest European producer of citrus, and is representative of the environmental changes triggered by innovations in orchard management. In order to determine the impact of land management on different soil quality parameters, twelve citrus orchards sites were selected with different land and irrigation management techniques. Soil samples were taken at two depths, 0-2. cm and 5-10. cm for studying soil quality parameters under the different treatments. Half of the studied orchards were organically managed and the other si…
A comparison of statistical methods and multi-criteria decision making to map flood hazard susceptibility in Northern Iran
2018
In north of Iran, flood is one of the most important natural hazards that annually inflict great economic damages on humankind infrastructures and natural ecosystems. The Kiasar watershed is known as one of the critical areas in north of Iran, due to numerous floods and waste of water and soil resources, as well as related economic and ecological losses. However, a comprehensive and systematic research to identify flood-prone areas, which may help to establish management and conservation measures, has not been carried out yet. Therefore, this study tested four methods: evidential belief function (EBF), frequency ratio (FR), Technique for Order Preference by Similarity To ideal Solution (TOP…
Coarse-Grained Barrier Trees of Fitness Landscapes
2016
Recent literature suggests that local optima in fitness landscapes are clustered, which offers an explanation of why perturbation-based metaheuristics often fail to find the global optimum: they become trapped in a sub-optimal cluster. We introduce a method to extract and visualize the global organization of these clusters in form of a barrier tree. Barrier trees have been used to visualize the barriers between local optima basins in fitness landscapes. Our method computes a more coarsely grained tree to reveal the barriers between clusters of local optima. The core element is a new variant of the flooding algorithm, applicable to local optima networks, a compressed representation of fitnes…
Climatic and anthropogenic influences on three burgundian watercourses : geoarchaelogy of crossing sites on Loire, Saône and Doubs during the Holocene
2015
A geoarchaeological study was led on four sections of the valleys of the Loire, Saône and Doubs rivers (Burgundy, France) in order to point out the factors influencing the alluvial dynamics on a multimillennial scale, and their effects on the preservation of archaeological information. Investigations started by roman and medieval remains of bridges discovered in active channels, were then carried out on larger parts of alluvial plains, and altogether allowed the evolutions of the channels during the Holocene period to be deducted. Various types of information on alluvial characteristics were crossed through time and space: ancient maps and XXth century or aerial photographs for centennial s…
Social support provided by adolescents following a disaster and perceived social support, sense of community at school, and proactive coping.
2012
Heightened levels of support provision are systematically observed in adults immediately following natural disasters, yet knowledge about adolescents' social support provision is less extensive. This longitudinal study of 262 adolescents assessed their help-providing behaviors during and after a flood. It was hypothesized that social support provided by adolescents would relate to subsequent perceptions of their relationships with others and perceptions of the self. Descriptive analyses demonstrated that the majority of respondents reported that they provided tangible, emotional, and informational support to others in need. A series of hierarchical multiple regression analyses indicated tha…
Drastic innovation reduces firms’ incentives to create divisions
2020
I study a game in which two firms create independent divisions, then they choose whether to do R&D so as to reduce their divisions’ marginal costs, and then the divisions compete in the market. I provide necessary and sufficient conditions under which the game has an equilibrium in pure strategies, and I show that the game has an equilibrium only if each firm threatens that if the rival creates more divisions it will use R&D to foreclose the market. The case we find in the literature, in which firms flood the market with their divisions, should happen only in industries with low returns to R&D.
R&D Reduces Firms' Incentives to Create Divisions
2017
I study a game in which two firms create independent divisions, then they choosewhether to do R&D so as to reduce their divisions' marginal costs, and then the divisions compete in the market. I provide necessary and sufficient conditions under which the game has an equilibrium in pure strategies, and I show that the game has an equilibrium only if each firm threatens that if the rival creates more divisions it will use R&D to foreclose the market. The case we find the literature, in which firms flood the market with their divisions, should happen only in industries with low returns to R&D.
Bio-imaging with the helium-ion microscope: A review
2021
Scanning helium-ion microscopy (HIM) is an imaging technique with sub-nanometre resolution and is a powerful tool to resolve some of the tiniest structures in biology. In many aspects, the HIM resembles a field-emission scanning electron microscope (FE-SEM), but the use of helium ions rather than electrons provides several advantages, including higher surface sensitivity, larger depth of field, and a straightforward charge-compensating electron flood gun, which enables imaging of non-conductive samples, rendering HIM a promising high-resolution imaging technique for biological samples. Starting with studies focused on medical research, the last decade has seen some particularly spectacular …
Maximum flood area during MIS 1 in the Almenara marshland (Western Mediterranean): Benthic foraminifera and sedimentary record
2018
The sedimentological and micropaleontological analysis of three mechanical cores in the marshland of Almenara (Valencian Community, Spain) has allowed the reconstruction of the Holocene evolution of this wetland. The cold and dry 8.2-ka event might be represented in Almenara by a massive carbonate precipitation bed, upon which mid- and late-Holocene sediments were subsequently deposited. The direct influence of sea-level changes has been recorded in the two cores (S-4 and S-5) located near the marsh barrier, at 400–450 m from the current coastline. The maximum flood area during MIS 1 (last 11,600 years) is represented in these cores by sediments indicative of different littoral subenvironm…