Search results for " web"
showing 10 items of 1173 documents
Mappe online e processi partecipativi innovativi per la costruzione di una nuova immagine del territorio
2013
Il presente research paper tratta le questioni relative al ruolo dell’informatica e della cartografia online in ambito geografico. A partire dai web-GIS si sono sviluppate e diffuse diverse tipologie di esperienze, meno tecniche e più vicine agli utenti non esperti: progetti di mappe partecipate, tools che permettono l’inserimento di informazioni georeferenziate sui social network, piattaforme e blog di città o di quartiere, software commerciali, e molto altro. In tale direzione si inserisce il percorso della mia ricerca di dottorato, sul rapporto tra i GIS, internet e i temi dell’etica e della giustizia sociale. La ricerca si pone l’obiettivo di un’analisi critica delle tecnologie citate, …
Recherche d'information dans les documents numériques : vers une variation des modalités d'exécution procédurale
2011
National audience; L'objectif de la recherche présentée est de tester l'efficacité cognitive d'un nouveau système technique facilitant la recherche d'information dans les documents numériques. Ce système utilise un dispositif de prévisualisation par transparence permettant à l'utilisateur de consulter aisément des pages en profondeur. Une étude expérimentale a été conduite auprès de 36 participants, dont 26 étudiants et 10 personnes âgées. La tâche de recherche d'information consistait à trouver un appartement cible possédant un ou plusieurs critères spécifiques dans un site web d'agence immobilière spécialement conçu et contrôlé pour l'étude. Deux versions de ce site ont été testées. L'une…
Responses of microbial-feeding nematodes to organic matter distribution and predation in experimental soil habitat
2001
Abstract Soils are spatially heterogeneous environments, a condition which is likely to affect the structure and function of soil food webs. To study the influence of soil organic matter distribution on decomposer food webs, we established microcosms that contained either: (1) large patches of initially sterile humus-litter mixture placed within sterile sand matrix (creating a large-patch habitat; LPH); or (2) blend of sand and humus-litter mixture (creating a small-patch habitat; SPH). Ten species of bacteria and ten species of fungi, and two bacterial-feeding ( Acrobeloides tricornis , Caenorhabditis elegans ) and two fungal-feeding ( Aphelenchus avenae , Aphelenchoides sp.) nematodes wer…
Widespread contribution of methane-cycle bacteria to the diets of lake profundal chironomid larvae.
2008
Reports of unexpectedly 13C-depleted chironomid larvae in lakes have led to an hypothesis that significant transfer of detrital organic matter to chironomid larvae may occur via methane-cycle bacteria. However, to date little is known of how such transfer might vary across species and lakes. We gathered data from 87 lakes to determine how widespread this phenomenon might be and to define boundaries for its likely magnitude. Carbon stable isotope values of chironomid larvae varied greatly between taxa. Very marked 13C-depletion was evident only in certain taxa, especially Chironomus plumosus, C. anthracinus, and C. tenuistylus, all characteristic of eutrophic or dystrophic lakes and known to…
Vertical stratification and trophic interactions among organisms of a soil decomposer food web – a field experiment using 15N as a tool
2002
Abstract In this field study, we explored the spatial segregation between the litter- and humus-inhabiting organisms of the detrital food web using 15 N-isotope technique. The study was established in 11 × 11 m plots fertilized with 15 N-labelled urea. Ten years after urea application, soil samples were taken, both from the litter layer and the combined F+H layer. The samples were analysed for N content and the proportion of 15 N in (i) the residual organic matter in the litter and F+H layer (excluding microbes), (ii) microbial biomass, and (iii) various feeding guilds of soil fauna. The basal resource, soil microbes, and the fauna were more enriched with 15 N in the F+H layer than in the l…
Sources of organic matter for inter-tidal consumers in Ascophyllum-shores (Sw Iceland): a multi stable isotope approach.
2007
Stable isotopes were used to examine the origin of organic matter in Icelandic Ascophyllum-based habitats, the role of different organic matters in filling intertidal food webs and the food preferences of the most abundant suspension feeders, grazers and predators. We selected three intertidal sites on the SW coast of Iceland where we sampled in early September 2004, organic matter sources (POM, SOM and most abundant primary producers, A. nodosum and F. vesciculosus) and the most abundant macrofauna species (barnacles, mussels, gastropods, sponge and crabs). Even though the primary production (Ascophyllum-based) was the same at the three study sites, the isotopic composition of common-among…
Mode I interlaminar fracture toughness of thin-ply laminates with CNT webs at the crack interface
2019
Abstract Pristine and functionalized carbon nanotube (CNT) webs were introduced at the interlaminar region of two different thin-ply carbon fibre reinforced polymer systems (NTPT 402 prepreg, and TeXtreme/SE84LV). The Mode I interlaminar fracture toughness (ILFT) for the NTPT 402 material was substantially lower. In contrast when SE84LV resin was used, the resistance curves were virtually unchanged and with no depreciation in the steady state value of the ILFT. This demonstrates that a careful choice of the resin is essential to permit the embedding of CNT webs in thin-ply laminates without compromising structural performance and opens a new way towards the development of multifunctional th…