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Advantages of Task-Specific Multi-Objective Optimisation in Evolutionary Robotics
Get PDFThe application of multi-objective optimisation to evolutionary robotics is receiving increas- ing attention. A survey of the literature reveals the different possibilities it offers to improve the automatic design of efficient and adaptive robotic systems, and points to the successful demonstrations available for both task-specific and task-agnostic approaches (i.e., with or without reference to the specific design problem to be tackled). However, the advantages of multi-objective approaches over single-objective ones have not been clearly spelled out and experimentally demonstrated. This paper fills this gap for task-specific approaches: starting from well-known results in multi-objective optimisation, we discuss how to tackle commonly recognised problems in evolutionary robotics. In particular, we show that multi- objective optimisation (i) allows evolving a more varied set of behaviours by exploring multi- ple trade-offs of the objectives to optimise, (ii) supports the evolution of the desired behav- iour through the introduction of objectives as proxies, (iii) avoids the premature convergence to local optima possibly introduced by multi-component fitness functions, and (iv) solves the bootstrap problem exploiting ancillary objectives to guide evolution in the early phases. We present an experimental demonstration of these benefits in three different case studies: maze navigation in a single robot domain, flocking in a swarm robotics con- text, and a strictly collaborative task in collective robotics
Caratterizzazione tassonomica e funzionale della fauna ittica nel Lago Maggiore con particolare riferimento alla competizione per le risorse alimentari e alle specie alloctone invasive di recente comaparsa
Get PDFNot availableRicerche sull\u27evoluzione del Lago Maggiore. Aspetti limnologici. Programma triennale 2013-2015. Campagna 2014. Caratterizzazione tassonomica e funzionale della fauna ittica nel Lago Maggiore con particolare riferimento alla competizione per le risorse alimentari e alle specie alloctone invasive di recente comaparsa. Composizione della comunit? ittica del Lago Maggiore: abbondanze assolute e relative; distribuzione verticale; caratterizzazione della comunit? ittica. Sovrapposizione nella nicchia trofica
Progetto "Acque pulite"
Get PDFAbstract not availableLe aree montane, soprattutto in territori ricchi di acqua come quello del Verbano Cusio Ossola e del bacino del Lago Maggiore, sono da sempre oggetto di utilizzo per la produzione di energia elettrica da fonti rinnovabili, principalmente attraverso impianti idroelettrici. Il giusto equilibrio tra il mantenimento della qualit? ecologica degli ecosistemi torrentizi e la produzione di energia elettrica da fonti rinnovabili non ? di facile attuazione, soprattutto in assenza di studi e sperimentazioni dedicate. Lo sfruttamento delle acque a scopo idroelettrico pu? determinare l\u27alterazione e, a volte, la perdita di habitat, causando una riduzione della biodiversit?, con effetti negativi maggiori sui taxa pi? sensibili (ad esempio macroinvertebrati e fauna ittica), causando contestualmente, il degrado della qualit? ecologica di parte o addirittura dell\u27intero corso d\u27acqua a seconda delle tipologie di prelievo/i a cui ? stato sottoposto. Diventa quindi importante, nel contesto locale, ma anche nazionale e internazionale, dove le energie rinnovabili sono un punto focale per la futura produzione di energia, trovare il giusto equilibrio tra la qualit? ecologica degli ecosistemi, e la richiesta di energia pulita e di sviluppo economico. E\u27 proprio in questo contesto che nasce l\u27idea del Progetto "Acque Pulite", che grazie alla disponibilit? e al finanziamento di IDROENERGY S.r.l. ha visto la realizzazione di uno studio pilota sul Torrente San Giovanni. Il Torrente San Giovanni ? uno dei principali immissari del Lago Maggiore e per tale motivo risulta importante conoscere la sua qualit? ecologica e gli effetti su di essa delle diverse attivit? umane che insistono all\u27interno del suo bacino. In particolare, con il Progetto "Acque Pulite" si sono voluti verificare gli effetti della presenza di un\u27opera di presa e di una traversa, costruite per scopo idroelettrico, sulla qualit? idro-morfologica, chimica e biologica dei tratti di torrente a monte e a valle di tali opere
Geo-statistical modeling of bulk deposition of inorganic nitrogen to Italian forests
Get PDFOpen field bulk deposition of inorganic nitrogen (N-NO3 + N-NH4) measured at Level II sites in Italy over the period 2000-2011 ranged from 3.9 to 16.2 kg ha-1 per year. A positive effect on basal area increment and C sequestration was detected at the same sites (Ferretti et al. 2014), but uncertainty remains on the overall impact of N deposition on the Italian forests. Data on N deposition at national level are available only in the form of large-scale, emission based models with relatively coarse spatial resolution (EMEP model, 50 x 50 km), which may be not reliable, when scaled down to local scales. Here we attempted to use measured Level II data from the Italian network to: . Validate existing and freely available EMEP data; and . develop an independent, deterministic geo-statistical model based on actual data measured at Level II sites over the period 2000 - 2011. To validate existing model output we run a simple exercise comparing spatial and temporal pattern of measured and modelled N deposition in relation to those measured at the Level II sites. For the geo-statistical model, we used the following predictors: latitude, longitude, elevation, aspect, annual precipitation and land use within three different buffer ranges: 3, 16 and 50 km radius from the very plot. Here we present the first outputs of the study. These results will be used in three directions: to derive N deposition estimates for Level I plots (and other sites); to feed correlative studies on the effect of N deposition on forests; to re-design the Italian deposition monitoring program, in terms of number of sites and their spatial allocation (retrospective design)
Interspecific interactions drive chitin and cellulose degradation by aquatic microorganisms
No full textComplex biopolymers (BPs) such as chitin and cellulose provide the majority of organic carbon in aquatic ecosystems, but the mechanisms by which communities of bacteria in natural systems exploit them are unclear. Previous degradation experiments in artificial systems predominantly used microcosms containing a single bacterial species, neglecting effects of interspecific interactions. By constructing simplified aquatic microbial communities, we tested how the addition of other bacterial species, of a nanoflagellate protist capable of consuming bacteria, or of both, affect utilization of BPs. Surprisingly, total abundance of resident bacteria in mixed communities increased upon addition of the protist. Concomitantly, bacteria shifted from free-living to aggregated morphotypes that seemed to promote utilization of BPs. In our model system, these interactions significantly increased productivity in terms of overall bacterial numbers and carbon transfer efficiency. This indicates that interactions on microbial aggregates may be crucial for chitin and cellulose degradation. We therefore suggest that interspecific microbial interactions must be considered when attempting to model the turnover of the vast pool of complex biopolymers in aquatic ecosystems
Again on the Excel sheet for testing water chemical analyses (atmospheric deposition, runoff, soil water)
Get PDFA simple Excel sheet to perform QA/QC on deposition and soil solutin sample
Designing Modelling Methods: The Learn PAd Scenario
No full textModelling methods are commodity to enable a conceptual knowledge base for smart and intelligent software. As programmes become more complex and requirements for such conceptual or semantic knowledge bases raises, the current development approaches reach their limits. The project Learn PAd applies a modeldriven approach for technology enhanced learning and knowledge management in the domain of public administration and elaborates a new way of designing and consequently in developing modelling methods. Based on the research of the Open Model Laboratory (OMiLAB) community, Learn PAd implemented a design and development tool for modelling methods. The result tested in the project, is currently used and improved in other projects and available for usage and contributions on the ADOxx.org portal
A single blueberry (Vaccinium corymbosum) portion does not affect markers of antioxidant defence and oxidative stress in healthy volunteers following cigarette smoking
No full textWe previously reported that a portion of blueberries reversed endothelial dysfunction induced by acute cigarette smoking. Since smoking-induced endothelial dysfunction is associated with a condition of oxidative stress, we evaluated whether the observed effect was mediated by modulation of markers of oxidative stress and antioxidant defence. Fourteen out of 16 male healthy smokers previously enrolled, participated in a three-armed randomized controlled study with the following experimental conditions: smoking treatment (one cigarette); blueberry treatment (300 g of blueberries) + smoking (one cigarette); control treatment (300 ml of water with sugar) + smoking (one cigarette).The cigarette was smoked 100 min after blueberry/control/ water consumption. Each treatment was separated by 1 week of washout period. Plasma vitamin (C, B12 and folate) and aminothiol concentrations, endogenous [formamidopyrimidine- DNA glycosylase (FPG)-sensitive sites] and oxidatively induced DNA damage (resistance to H2O2-induced DNA damage) in peripheral blood mononuclear cells (PBMCs) were measured at baseline and 20, 60, 90, 120 min and 24 h after smoking. In conclusion, the consumption of a single blueberry portion failed to modulate markers of oxidative stress and antioxidant defence investigated in our experimental conditions. Further studies are necessary to elucidate this finding and help clarifying the mechanisms of protection of blueberries against smoking-induced endothelial dysfunction
Interactional Leader-Follower sensorimotor communication strategies during repetitive joint actions
No full textNon-verbal communication is the basis of animal interactions. In dyadic leader-follower interactions, leaders master the ability to carve their motor behaviour in order to \u27signal\u27 their future actions and internal plans while these signals influence the behaviour of follower partners, who automatically tend to imitate the leader even in complementary interactions. Despite their usefulness, signalling and imitation have a biomechanical cost, and it is unclear how this cost-benefits trade-off is managed during repetitive dyadic interactions that present learnable regularities. We studied signalling and imitation dynamics (indexed by movement kinematics) in pairs of leaders and followers during a repetitive, rule-based, joint action. Trial-by-trial Bayesian model comparison was used to evaluate the relation between signalling, imitation and pair performance. The different models incorporate different hypotheses concerning the factors (past interactions versus online movements) influencing the leader\u27s signalling (or follower\u27s imitation) kinematics. This approach showed that (i) leaders\u27 signalling strategy improves future couple performance, (ii) leaders used the history of past interactions to shape their signalling, (iii) followers\u27 imitative behaviour is more strongly affected by the online movement of the leader. This study elucidates the ways online sensorimotor communication help individuals align their task representations and ultimately improves joint action performance