[show abstract][hide abstract] ABSTRACT: European Alpine glaciology has a long tradition of studies and activities, in which researchers have often relied on the field work of some specialized volunteer operators. Despite the remarkable results of this cooperation, some problems in field data harmonization and in covering the whole range of monitored glaciers are still present. Moreover, dynamics of reduction, fragmentation and decline, which in recent decades characterize Alpine glaciers, make more urgent the need to improve spatial and temporal monitoring, still maintaining adequate quality standards. Scientific field monitoring activities on Alpine glaciers run parallel to a number of initiatives by individuals and amateur associations, keepers of alternative, experiential and para-scientific knowledge of the glacial environment. Problems of harmonization, coordination, recruitment and updating can be addressed with the help of a collaborative approach—citizen science-like—in which the scientific coordination guarantees information quality and web 2.0 tools operate as mediators between expert glaciologists and non-expert contributors. This paper gives an overview of glaciological information currently produced in the European Alpine region, representing it in an organized structure, functional to the discussion. An empowering solution is then proposed, both methodological and technological, for the integration of multisource data. Its characteristics, potentials and problems are discussed.
ISPRS International Journal of Geo-Information. 08/2013; 2:680-703.
[show abstract][hide abstract] ABSTRACT: In 2005, the EU made the strategic choice of developing a space-based
programme, called Global Monitoring for Environment and Security (GMES).
GMES is an independent Earth monitoring initiative led by the European
Union and carried out in partnership with the Member States and the
European Space Agency (ESA). Its primary objective is to provide
information services that give access to accurate data and information
in the field of the environment and security and are tailored to the
needs of users. However, at the regional level, stakeholders are often
not aware about the potential benefits of services Europe's GMES
initiative can provide; yet Europe's ca. 350 regions represent a large
reservoir of potential GMES users where GMES services can add value to
existing services. Refining data, products and services from global GMES
services in the various domains (i.e. land, marine, atmosphere,
emergency response, security and climate change), GMES downstream
services may be customised to individual user needs, many of which are
to be found a the regional level. Within a number of regions, links
between the different types of stakeholders have grown over the years.
Often, individual actors have developed inter-regional links but their
linkage is in most cases not formalised. When looking at the European
scale, that overall awareness of GMES downstream opportunities is still
very low with respect to the potential benefits regions could draw from
a wider participation. However, being aware of the potential of GMES, of
the important role they can play and of the need for exchanging
experiences, pioneering Local and Regional Authorities (LRAs) intending
to retrieve benefit from space technologies, including GMES, have now
started to collaborate within structured networks, NEREUS being the most
advanced example. The logically next step is that LRAs engage in a
dialogue with service-industry and European decision-makers to maximize
the benefits from these innovative tools which have significant impact
on the economy, environment and the quality of life of the citizens To
this aim since 2011 the system of Regional Contact Offices (RCOs) was
promoted by the EU FP7 DORIS_Net (Downsteam Observatory organized by
Regions Active in Space - Network, http://www.doris-net.eu/) project as
the regional link to the services provided by the European GMES
programme. Since then a first nucleus of 12 pilot European Regions were
working together establishing 6 first RCOs around Europe. This paper
will present RCOs network goals, achievements and perspectives as well
as its planned actions devoted to improve quality of Space Technology
products from one side, to promote awareness and use of them by
potential end-users (and particularly LRAs), from the other side.
[show abstract][hide abstract] ABSTRACT: Since fire is a major threat to forests and wooded areas in the
Mediterranean environment of Southern Europe, systematic regional fire
monitoring is a necessity. Satellite data constitute a unique
cost-effective source of information on the occurrence of fire events
and on the extent of the area burned. Our objective is to develop a
(semi-)automated algorithm for mapping burned areas from medium spatial
resolution (30 m) satellite data. In this article we present a
multi-criteria approach based on Spectral Indices, soft computing
techniques and a region growing algorithm; theoretically this approach
relies on the convergence of partial evidence of burning provided by the
indices. Our proposal features several innovative aspects: it is
flexible in adapting to a variable number of indices and to missing
data; it exploits positive and negative evidence (bipolar information)
and it offers different criteria for aggregating partial evidence in
order to derive the layers of candidate seeds and candidate region
growing boundaries. The study was conducted on a set of Landsat TM
images, acquired for the year 2003 over Southern Europe and
pre-processed with the LEDAPS (Landsat Ecosystem Disturbance Adaptive
Processing System) processing chain for deriving surface spectral
reflectance ρi in the TM bands. The proposed method was
applied to show its flexibility and the sensitivity of the accuracy of
the resulting burned area maps to different aggregation criteria and
thresholds for seed selection. Validation performed over an entire
independent Landsat TM image shows the commission and omission errors to
be below 21% and 3%, respectively.
ISPRS Journal of Photogrammetry and Remote Sensing 04/2012; · 3.31 Impact Factor
[show abstract][hide abstract] ABSTRACT: A straightforward way to map burned areas from remotely sensed imagery is to integrate partial evidence of burn provided by multiple spectral indices (SIs). Our approach relies on fuzzy set theory to generate integrated layers of overall positive evidence (PE) and negative evidence (NE) scores. In order to reduce commission errors, we propose the use of NE for revising the overall PE. Revised layers are input for a region growing algorithm to produce a map of burned areas. Thematic Mapper (TM) images, acquired over the Mediterranean area, were used to derive the SIs and to define the soft constraints (membership functions). The performance of the revision process is tested for a TM image acquired over Portugal: The revision decreases the commission error from 59.5% to 1.3% and increases the overall accuracy from 42.6% up to 91.3%.
IEEE Geoscience and Remote Sensing Letters - IEEE GEOSCI REMOTE SENS LETT. 01/2012; 9(3):363-367.
[show abstract][hide abstract] ABSTRACT: Spatial assessment of environmental phenomena at regional/global scale involves the analysis and fusion of multiple, complex, multidisciplinary, and large-scale information. Since very often reliable models of such phenomena are lacking, the “syndrome approach” has been adapted to this purpose. In this context, there is a strong need for frameworks capable of handling data from heterogeneous sources in order to fuse them into synthetic indicators by modelling the uncertain and incomplete knowledge of the phenomenon.The approach here proposed models a syndrome by soft revision of bipolar information having heterogeneous role: a set of contextual conditions constraining the flourishing of the syndrome (negative information), identified on the basis of the expert's knowledge, and a typical pattern of notable symptoms (positive information) that are indeed proxies of observations of the syndrome occurrence. Specifically, three soft revision strategies are defined in the paper to combine negative and positive information whose overall aim is to define indicators of occurrence of an environmental syndrome with distinct objectives. The main concern of the first two revisions is to reduce the incoherence of bipolar information by taking into account the information reliability: the first strategy models a cautious decision attitude by eliminating incoherence and by modelling priorities of either negative or positive information and their partial trust, while the second strategy models a cautious and precautionary decision attitude giving credit to observations by taking into account False Negatives and False Positives. Finally, the third strategy models decision attitudes characterized by distinct level of risk. The proposed methodology is exemplified by a real case study whose objective is to define an indicator of the Rural Exodus syndrome for the Mediterranean region. In this case the method fuses biophysical related variables derived from Earth Observation (EO) data with geophysical and socioeconomic conditions based on the proposed strategies.
Environmental Modelling and Software 01/2012; 36:131-147. · 3.48 Impact Factor
[show abstract][hide abstract] ABSTRACT: Ill-known environmental phenomena are often modeled by means of multisource spatial data fusion. Generally, these fusion strategies
have to cope with distinct kinds of uncertainty, related to the ill-defined knowledge of the phenomenon, the lack of classified
data, the distinct trust of the information sources, the imprecision of the observed variables. In this chapter we discuss
the advantage of modeling multisource spatial data fusion in the environmental field based on the OWA operator, and overview
two applications. The first application is aimed at defining an environmental indicator of anomaly at continental scale based
on a fusion of partial hints of evidence of anomaly. The second application computes seismic hazard maps based on a consensual
fusion strategy defined by an extended OWA operator that accounts for data imprecision, and reliability of the data sources.
In particular, the proposed fusion function models a consensual dynamics and is parameterized so as to consider a varying
spatial neighborhood of the data to fuse.
[show abstract][hide abstract] ABSTRACT: This study adopts the “syndrome approach”, originally defined by the Potsdam Institute for Climate Impact Research (PIK), (Downing et al., 2002) to assess and map rural land abandonment (RLA), that occurred during the period 1990–2005 within the wider Mediterranean area. The basic idea behind the syndrome approach is to describe change processes by archetypical, dynamic, and co-evolutionary patterns of civilization–nature interactions. In the frame of the Rural Exodus Syndrome the RLA can be interpreted as the occurrence of environmental degradation through the abandonment of traditional agricultural practices. Multi-source spatial data, including biophysical-related variables mainly derived from Earth Observation as well as socio-economical GIS-based data, were used to define proxies for expected underlying processes and drivers of the mentioned syndrome. The analysis of data is rooted in the fuzzy set theory and approximate reasoning techniques which allows for the handling of uncertain and imprecise knowledge of environmental systems. Generalized Conjunction/Disjunction operators (GCD) were applied to compute intermediate indicator score maps representing the conditions that may affect the RLA, and a bipolar operator was used to combine mandatory and favouring conditions with the aim of generating a RLA indicator. The indicator expresses the detailed location and severity, or degree, of the syndrome. The Northern Mediterranean was generally found to suffer from RLA to a distinctly higher degree than the Southern Mediterranean. Reported abandonment studies from the existing literature, the European CORINE land cover map, and the Less Favoured Areas (LFA) map all supported the findings by confirming plausibility through convergence of evidence from comparisons with different types of independent information. This spatially highly-detailed results obtained may be of particular interest to policy and decision makers involved in rural development planning in the conceived areas.
Global and Planetary Change 01/2011; 79(1–2):20-36. · 3.16 Impact Factor
[show abstract][hide abstract] ABSTRACT: In this paper we analyze the limitations of current recommendations of the INSPIRE (Infrastructure for Spatial Information in Europe) Directive as far as the temporal metadata definition for discovery purposes, and propose its extension so as to allow the representation and management of imperfect spatio- temporal metadata. We propose to extend the metadata in order to cope with the requirements of both metadata producers, who often are unable to specify precise values, and users who submit queries to catalog services for discovering interesting data, who may express soft selection conditions on metadata values. The proposal is illustrated and explained through an example taken from an active Spatial Data Infrastructure (SDI).
Proceedings of the Joint 2009 International Fuzzy Systems Association World Congress and 2009 European Society of Fuzzy Logic and Technology Conference, Lisbon, Portugal, July 20-24, 2009; 01/2009
[show abstract][hide abstract] ABSTRACT: Environmental status assessment and monitoring can be performed by the integration of multi-source datasets at continental and global scales. We propose a methodology for the development of a new anomaly indicator (AI) which can highlight the occurrence of anomalous conditions in a synthetic fashion by analysis of a set of spatial input data. Anomalous conditions are defined relative to long-term average assumed as normal or reference status of the vegetated land surface. The indicator is defined according to fuzzy set theory which is a powerful means of handling uncertain and imprecise knowledge of environmental systems. The indicator integrates, in an innovative way, the anomaly scores of a set of contributing factors extracted from the analysis of historical time series, mainly of Earth observations data. These time series are used to automatically derive the fuzzy membership functions that quantify the contribution of each factor to the final indicator. No reference data and expert knowledge are strictly required for the implementation of the AI although the methodology allows customization where this type of information is available. The method was tested over the African continent for the period 1996–2002; monthly AI values were derived with input datasets of vegetation phenology and rainfall estimates. The output AI continental maps bring new information by integrating multiple factors and they highlight patterns of anomalous conditions of the status of the environment. The analysis of the correlation with the El Niño Southern Oscillation (ENSO) shows that the AI is able to identify the effects of this phenomenon and its spatio-temporal dynamics. The 1997–1998 and 2000–2001 ENSO events are clearly highlighted by the highest AI values in specific regions of the continent. The indicator proposed is a valuable tool which can help guide in depth and detailed investigations of environmental conditions at local scale.
[show abstract][hide abstract] ABSTRACT: The monitoring of the environment's status at continental scale involves the integration of information derived by the analysis of multiple, complex, multidisciplinary, and large‐scale phenomena. Thus, there is a need to define synthetic Environmental Indicators (EIs) that concisely represent these phenomena in a manner suitable for decision‐making. This research proposes a flexible system to define EIs based on a soft fusion of contributing environmental factors derived from multi‐source spatial data (mainly Earth Observation data). The flexibility is twofold: the EI can be customized based on the available data, and the system is able to cope with a lack of expert knowledge. The proposal allows a soft quantifier‐guided fusion strategy to be defined, as specified by the user through a linguistic quantifier such as ‘most of’. The linguistic quantifiers are implemented as Ordered Weighted Averaging operators. The proposed approach is applied in a case study to demonstrate the periodical computation of anomaly indicators of the environmental status of Africa, based on a 7‐year time series of dekadal Earth Observation datasets. Different experiments have been carried out on the same data to demonstrate the flexibility and robustness of the proposed method.
International Journal of Geographical Information Science. 01/2008; 22:781-799.
[show abstract][hide abstract] ABSTRACT: This paper is concerned with the problem of indexing remote sensing images. This kind of images has a semantics mainly related
to the image spectral properties. For these reasons the spectral properties can be considered as effective image descriptors.
The model proposed in this paper assumes that the image descriptors are spectral regions and their spectral signatures. By
the application of a clustering algorithm each image is segmented into a set of spectral regions to be associated to basic
(pre-defined) ground cover classes. To take into account the uncertainty that often affects the cluster labelling process
the indexing model generates for each region and each reference class a possibility degree indicating the possibility that
the region corresponds to that class. The uncertainty of this association is explicitly modelled, and allows the definition
of a more flexible image representation with respect to a crisp approach.
Image and Video Retrieval: Third International Conference, CIVR 2004, Dublin, Ireland, July 21-23, 2004. Proceedings; 01/2004
[show abstract][hide abstract] ABSTRACT: In this contribution a dual representation of spatio-temporal phenomena whose observation is affected by uncertainty is proposed in the context of fuzzy set and possibility theory. The concept of fuzzy time validity of a snapshot of a dynamic phenomenon is introduced as well as the concept of possible spatial reference of the phenomenon at a given time instant. Then some methods to answer queries imposing constraints on either the temporal information or the spatial information are defined. Finally a mechanism to generate virtual snapshots of the phenomenon, showing its possible spatial reference at consecutive time instants, is described.
Fuzzy Sets and Systems - IFSA 2003, 10th International Fuzzy Systems Association World Congress, Istanbul, Turkey, June 30 - July 2, 2003, Proceedings; 01/2003
[show abstract][hide abstract] ABSTRACT: This contribution aims to shortly describe a data structure for creating and managing archives of thematic maps derived by classifying remotely sensed images by soft techniques (soft maps). Unlike traditional models for managing spatial data, the main key feature for query formulation is time, thus improving the investigation on changes occurred in time ranges. The data structure originally extends time-based models to soft maps, thus promoting a retrieval by changes approach also in the monitoring of phenomena for which hard classifications are not sufficiently accurate nor complete.The data structure has been implemented in a system, which is also described, available today in a Windows version. It has been applied to the monitoring of variations of Alpine glaciers.
[show abstract][hide abstract] ABSTRACT: This paper introduces BANCO (Browsing Adaptive Network for Changing user Operativity) - a software prototype designed to explore how to support users in their interaction with remote sensing, spatial and multimedia data accessed from remote Web servers - and how standard technologies evolve spatial and non-spatial Web sites. Meeting the request of new software environments, technologically up to date and handling both remote sensing and spatial data, BANCO proposes a novel architecture, in which users can, at the client side, customize their environment according to their role, culture and needs. As far as new technologies are concerned, BANCO relies on Scalable Vector Graphics (SVG) - the recommendation of W3C for representing vector graphics on the Web - which is applied to specify not only the display properties but also the interaction mechanisms and the behaviour of 'objects' and tools, well beyond its original scope of mark-up language for vector graphics. The prototype is illustrated within a case study aimed at monitoring Alpine glaciers on the Web via information derived from remote sensing images.
International Journal of Remote Sensing 01/2003; 24(20):3903-3916. · 1.14 Impact Factor
[show abstract][hide abstract] ABSTRACT: This paper proposes a design methodology, aimed at bridging the communicational gap often existing between users and visual interactive system (VIS) designers. The methodology is based on a novel design strategy, here called the 'visual workshop hierarchy' strategy and recognizes that the users of a VIS are experts in some domain different from computer science, who need to perform some task. The strategy allows some users to directly collaborate to the VIS design process. The strategy feasibility is discussed outlining its implementation through BANCO, a Web-based prototype.
Human Centric Computing Languages and Environments, 2002. Proceedings. IEEE 2002 Symposia on; 02/2002
[show abstract][hide abstract] ABSTRACT: The purpose of this paper is to describe a system for creating and managing archives of thematic maps derived from remote sensing images by soft classification techniques. Unlike the traditional spatial approach, the main key feature for query formulation is time. This improves the investigation on changes that occurred in time ranges. Both the functionalities of the system and the data structure on which it is based are described. Since the system has been tested in monitoring Alpine glacier variations with the purpose of exploring the effects of climate change, the validation methodology and its results are illustrated as well.
[show abstract][hide abstract] ABSTRACT: This paper proposes a new effective strategy for designing and implementing interactive systems overcoming culture, skill and situation hurdles in Human-Computer Interaction (HCI). The strategy to identify and reduce these hurdles is developed in the framework of a methodology based on a recently introduced model of HCI, and exploits the technological innovations of XML (Extensible Markup Language). HCI is modelled as a cyclic process in which the user and the interactive system communicate by materializing and interpreting a sequence of messages. The interaction process is formalized by specifying both the physical message appearance and the computational aspect of the interaction. This formalization allows the adoption of notation traditionally adopted by users in their workplaces as the starting point of the interactive system design. In this way, the human–system interaction language takes into account the users’ culture. Moreover, the methodology permits user representatives to build a hierarchy of systems progressively adapted to users’ situations, skills and habits, according to the work organization in the domain considered. The strategy is proved to be effective by describing how to implement it using BANCO (Browsing Adaptive Network for Changing user Operativity), a feasibility prototype based on XML, which allows the hierarchy implementation and system adaptations. Several examples from an environmental case under study are used throughout the paper to illustrate the methodology and the effectiveness of the technology adopted.
Universal Access in the Information Society 01/2002; 1:288-304. · 0.53 Impact Factor
[show abstract][hide abstract] ABSTRACT: This paper proposes a new strategy for designing e-documents adaptable to user’s aims and habits. This strategy is based on
the creation of a cascade of interaction environments requiring the local adaptation of the e-documents. The strategy is supported
by a recently introduced model of Human Computer Interaction, and made effective by the development of BANCO, an environment
allowing Web modification by the users at the client side.
Adaptive Hypermedia and Adaptive Web-Based Systems, Second International Conference, AH 2002, Malaga, Spain, May 29-31, 2002, Proceedings; 01/2002