447 research outputs found
Paesaggi marginali e paesaggi mediati
L’evoluzione socio-economica ha radicalmente cambiato i paesaggi dell’europa, che erano stati plasmati dalle comunità rurali. Il recupero, con una valorizzazione economica e simbolica, è possibile solo con una nuova consapevolezza e responsabilità dell’intera società
Educational or emotional languages? An interactive experiment with the Lucanian flora (S-Italy)
In the frame of dissemination activities for a still-in-progress work
on the Sites of Community Importance (see EU Directive 92/43) of Basilicata
(a region of Southern Italy), an interactive tool (IIT) for the identification of
vascular plants growing there has been illustrated to two groups of people,
following two different approaches: one focused on textual parts and on
scientific accuracy, the other on images and on the visual comparison
of different objects. The reactions were measured in terms of number of
accesses to the IIT, elapsed time from the demonstration to the first individual
access, and number of queries in the first week after the IIT was distributed.
The most clicked options were recorded as well. People who followed the
emotional/visual approach proved to be significantly more interested in the
IIT than those who followed the descriptive/scientific approach. It seems that
to raise the interest of non-experts to the identification of plant species and,
more in general, to the study of biodiversity, words should be kept at minimum,
while the quality of the images and their “appeal” are essential
Plant communities, synusiae and the arithmetic of a sustainable classification
We propose an equation to evaluate the efficiency of a classification as a function of the effort required and the population size of data collectors. The formula postulates a “classification efficiency coefficient”, which relates not only to the complexity of the object to be classified, but also to the data availability and representativeness. When applied to the classification of phytocoenoses, the equation suggests that a classification system based on vascular plants offers the best compromise between sampling effort, resolution power and data availability. We discuss the possibility of basing a vegetation classification on plot records for all macroscopic photoautotrophic organisms co-occurring in the vertical projection of a given ground area, as recently suggested by some authors. We argue that the inclusion of cryptogams in the description of phytocoenoses dominated by vascular plants should rely on a synusial approach, conceived as complementary to the traditional Braun-Blanquet approach
A new species of Anthemis sect. Hiorthia (Asteraceae) from SE Sicily
A new species of Anthemis sect. Hiorthia (Asteraceae) is described from Sicily. This taxon, named A. pignattiorum, is confined to a restricted area of the Hyblaean territory (SE Sicily), in the Natural Reserve of Cava Grande (Cassibile, Siracuse), where it takes shelter on carbonate rocky habitat and participates, with other Sicilian endemic taxa, to the composition of a termophilous chasmophytic community (Putorio calabricae–Micromerietum microphyllae)
I tetti verdi di tipo estensivo : biodiversità ad alta quota
Le città sono state paragonate da Odum a degli organismi eterotrofi che basano la loro crescita ed espansione sull’uso indiscriminato di risorse e sono causa di perdita irreversibile e frammentazione degli habitat naturali. I tetti verdi rappresentano uno strumento essenziale di mitigazione e compensazione ambientale all’interno del tessuto urbano dove, l’alta densità edilizia e l’elevato disturbo antropico concedono poco spazio alle dinamiche naturali. In particolare, i tetti verdi per la biodiversità caratterizzati da mosaici di micro-habitat diversi e contigui tra loro, possano ospitare specie con caratteristiche morfo-funzionali diverse. L’approccio noto come habitat template, consiste nel selezionare le specie vegetali adatte alle condizioni sui tetti estensivi tra quelle che in natura crescono in condizioni simili e.g. spessore di substrato ridotto e povero di sostanze nutritive, lunghi periodi di aridità. L’approccio fitosociologico prevede l’individuazione di habitat analoghi non solo come riferimento da cui estrapolare le specie vegetali, ma come modello per aggregare le piante in consorzi specifici, così come suggerisce l’interpretazione fitosociologica della natura.Cities are defined as heterotrophic organisms (Odum, 1983) as they consumes a huge amount of resources and causes habitat loss and fragmentation. Green roofs represents a fundamental mean of ecological compensation within the built environment, i.e. in highly altered and disturbed places by humans. In particular, green roofs for biodiversity (or biodiversity green roofs), being characterised by different but contiguous microhabitat (habitat mosaics or patches), can host several species with different functional traits. The methods known as habitat template consists of choosing suitable plant species for green roofs among the one that live in nature under similar conditions e.g. shallow and nutrient poor substrate, high drought. The phytosociological approach considers habitat analogue not only as species pools, but also as a model to group plants in specific associations as suggested in the phytosociological interpretation of nature
The cooperative effect of load and disorder in thermally activated rupture of a two-dimensional random fuse network
A random fuse network, or equivalently a two-dimensional spring network with
quenched disorder, is subjected to a constant load and thermal noise, and
studied by means of numerical simulations. Rupture is thermally activated and
the lifetime follows an Arrhenius law where the energy barrier is reduced by
disorder. Due to the non-homogeneous distribution of forces from the stress
concentration at microcrack tips, spatial correlations between rupture events
appear, but they do not affect the energy barrier's dependence on the disorder;
they affect only the coupling between the disorder and the applied load
A real-time 3D reconstruction of staircases for rehabilitative exoskeletons
In medical contexts, the use of assistive exoskeletons
for the rehabilitation of people with impaired mobility represents
a common practice. Recent advances suggest that, soon, such
mechatronic systems will also be used to assist people in their
everyday life. In order to reach such target, exoskeletons must
become able to perceive the environment. To this purpose, a
system for the parametric identification of a staircase is proposed
in this paper. More precisely, given a staircase of unknown
geometry, the system identifies its 3D shape. Furthermore, it
also estimates the reciprocal orientation and distance between the
exoskeleton and the staircase. Differently from other approaches,
this result is achieved by means of low cost devices: an inertial
measurement unit, two ranging sensors, and an Arm-Cortex
processor. Starting from the ranging sensors acquisitions, the
staircase model is identified in real time, during the execution
of a step. The proposed procedure is based on an extended
recursive total least squares strategy, in order to fully exploit
the computational capabilities of the Arm processor, and it
is characterized by execution times smaller than 10 −3 s. The
estimation algorithm has been tested on an actual exoskeleton
and the resulting experimental outcomes are compared with the
results obtained through alternative methods
Impact of information technology on future floras
Some important facilities offered by the information technology to innovate the development of traditional floras are illustrated and discussed. These include: random access interactive tools for the identification of species, low cost, easy updating, virtually unlimited space for high resolution images and texts, on-line utilities, strong synergy between authors and users. It is argued
that the combination of printed books with integrated digital utilities and data-sources is the most desirable structure for future floras
“Flora Italiana Digitale”: an interactive identification tool for the Flora of Italy
The digital facilities of the second edition of Pignatti’s “Flora d’Italia”
are presented. A software, called FID (i.e. “Flora Italiana Digitale”) will link
together a random-access interactive identification tool, a thesaurus, synoptic
tables and one template for each single species, including a distribution map
(referred to the Italian regions), “ecograms”, a text-box and up to 24 highresolution
colour images. The FID follows a “shareware phylosophy”. All
contents and images can be integrated and/or replaced over time, in order
to continuously improve the diagnostic and qualitative performance of the
provided utilities. Ideally, the community of users should interact on the web,
so that every user could easily become content provider
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