197,365 research outputs found
Cognitive change in learning from text : gesturing enhances the construction of the text mental model
No full textThe literature on co-speech gestures has revealed a facilitating effect of gestures on both the listener’s discourse comprehension and memory, and the speaker’s discourse production. Bucciarelli (2007) and Cutica and Bucciarelli (2008) advanced a mental model account for the cognitive change produced by gestures: Gestures, whether observed or produced, favour the construction of a mental model of the discourse they accompany. In this paper, we focus on gesturing while studying, assuming that gesturing
while reading a text also favours the construction of a mental model of the text. In two experiments we
invited adult participants to study two scientific texts and confirmed the predictions deriving from the
assumption that gestures favour the construction of a mental model of the text: Gesturing while studying
resulted in more correct recollections and text-based inferences (Experiment 1) and loss of verbatim
recall (Experiment 2)
Dealing with uncertainty in planning of energy storage systems in power distribution networks
No full textIn the last decades, power systems are undergoing major modifications, mostly driven by the climate change. This increasing awareness has brought national policies to meet the necessities of reducing CO2 emissions and the use of fossil fuels by incentivizing renewable energy sources. At the same time, the latest advances in the field of distributed energy resources, including more efficient photovoltaic, wind and energy storage systems, have raised the interest in taking full advantage of these technologies, for instance to reduce grid power losses.
As a consequence, these new challenging environmental and economic targets set by government policies are driving a dramatic transformation of power supply in electricity systems, with traditional thermal power plants getting off the stage, replaced by distributed generation. Moreover, non-dispatchable distributed energy resources such as wind and photovoltaic systems, with their dependance on weather and climate conditions, introduce new sources of uncertainty in power system operation.
Energy storage systems represent a solution for enhancing grid performance, reliability, flexibility and security in the presence of renewables. Charging of the storage devices installed in a distribution grid may help avoid or mitigate the reverse power flow upstream the transformers in case of an excess of generation from distributed generators, without resort to curtailment of generated power. Moreover, use of ESSs may help smooth the fast voltage variations arising as one of the tangible effects of sudden changes in energy production and/or demand patterns.
This thesis addresses the problem of the optimal energy storage system allo- cation in power distribution networks with high penetration of renewables. This is a problem which has received increasing attention in the literature, due to the numerous benefits that the use of energy storage systems brings to the power system and its stakeholders. The considered decision problem consists of defining the number of storage units to be deployed, their locations (placement) and sizes (sizing). This decision is made at the planning stage, when the future realizations of demand and generation in the network are unknown.
In this thesis uncertainty is accounted for by formulating the allocation problem in a scenario-based stochastic optimal power flow framework. The high dimensionality of the sources of uncertainty involved, puts additional burden on the solution of the allocation problem which, even in the deterministic case, is subject to the combinatorial complexity intrinsic in the placement problem, and the nonconvexity of power flow equations. The main contribution of this thesis is therefore to cope with the prohibitive computational complexity of the large-scale mixed-integer nonconvex optimization problems formulated for optimal allocation. This is done along two directions. On the one hand, the thesis proposes a scenario- reduction technique which makes it possible to solve at the optimum the sizing problem over a large set of scenarios by solving a smaller problem over a selected set of scenarios. On the other hand, the combinatorial nature of optimal placement problems is overcome through a near-optimal placement strategy with well-defined performance guarantees based on submodularity theory and greedy methods. The proposed techniques take advantage of recent developments on convex relaxations and linear approximations of power flow equations to tackle the solution of the considered optimal power flow problems.
Numerical results and sensitivity analyses are reported to show the effectiveness of all the procedures and approaches presented in this thesis
Homemade podcast: il caso del liceo Melchiorre Gioia di Piacenza
No full textQuesto contributo ha preso forma nel gruppo di co-ricerca sulla flipped classroom del Movimento Avanguardie Educative, un progetto nato dall’iniziativa di INDIRE e di ventidue scuole con l’obiettivo di investigare possibili strategie di disseminazione e messa a sistema dell’innovazione all’interno della scuola italiana. Il Liceo M. Gioia di Piacenza, una delle scuole fondatrici del Movimento, da settembre 2013 ha attivato la sezione E-SCHOOL, sperimentazione di insegnamento in modalità flipped classroom. Nel Maggio del 2019 sono stati realizzati due focus group e due interviste strutturate finalizzati a ricostruire il percorso della sperimentazione, giunta al termine del secondo quinquennio (a.s. 2018/2019), a partire dalle motivazioni originarie che hanno spinto i suoi protagonisti a prendervi parte, e a metterne in luce punti di forza e di debolezza
Effect of prothrombin 19911 A>G polymorphism on the risk of cerebralsinus-venous thrombosis.
No full textEur J Neurol. 2010 Dec;17(12):1482-5.
Effect of prothrombin 19911 A>G polymorphism on the risk of cerebral
sinus-venous thrombosis.
Martinelli I, Bucciarelli P, De Stefano V, Passamonti SM, Menegatti M, Tormene D,
Tosetto A, Mannucci PM.
A. Bianchi Bonomi Haemophilia and Thrombosis Center, Department of Internal
Medicine and Medical Specialties, Fondazione IRCCS Ca' Granda - Ospedale Maggiore
Policlinico, University of Milan, Milan, Italy. [email protected]
BACKGROUND AND PURPOSE: The A>G polymorphism at position 19911 of the prothrombin
gene is associated with a mildly increased risk of venous thromboembolism, alone
or in association with such common thrombophilia mutations as factor V Leiden and
prothrombin 20210 GA. Its role in cerebral sinus-venous thrombosis (CSVT) is not
known.
METHODS: The presence of prothrombin 19911 A>G was investigated in a case–control
study of 107 patients with cerebral thrombosis and factor V Leiden (n = 25),
prothrombin 20210 GA (n = 47), without known thrombophilia (n = 35) and 842
healthy individuals with the corresponding coagulation profile.
RESULTS: Prothrombin 19911 A>G did not increase the risk of CSVT in carriers of
factor V Leiden (adjusted odds ratio 1.6, 95%CI 0.6–4.7), prothrombin 20210 GA
(odds ratio 1.1, 95%CI 0.6–2.2), nor in patients without known thrombophilia
(odds ratio 1.3, 95%CI 0.5–3.1).
CONCLUSIONS: Prothrombin 19911 A>G polymorphism does not appear to be a risk
factor for CSVT, alone or in association with factor V Leiden or prothrombin
20210GA.
© 2010 The Author(s). European Journal of Neurology © 2010 EFNS.
PMID: 20482605 [PubMed - indexed for MEDLINE
The deep versus the shallow : effects of co-speech gestures in learning from discourse
No full textThis study concerned the role of gestures that accompany discourse in deep learning processes. We assumed that co-speech gestures favor the construction of a complete mental representation of the discourse content, and we tested the predictions that a discourse accompanied by gestures, as compared with a discourse not accompanied by gestures, should result in better recollection of conceptual information, a greater number of discourse-based inferences drawn from the information explicitly stated in the discourse, and poorer recognition of verbatim of the discourse. The results of three experiments confirmed these predictions
Integration of frequency domain wideband antenna nulling and wavenumber domain image formation for multi-channel SAR
No full textA Multichannel Synthetic Aperture Radar (M-SAR) exploiting an antenna nulling based Electronic Counter-Counter Measures (ECCM) technique shall be able to cancel the effects of noise-like interferences over the collected SAR data. Since SAR systems often work with wide bandwidths to provide high resolution images, ECCM technique must account for the presence of wideband interference signal. In this paper we consider a wideband antenna nulling technique based on space-frequency adaptive nulling and we propose an integration of the WB antenna nulling scheme within the focusing algorithm for M-SAR systems, thus allowing a fusion between ECCM and usual SAR processing steps. The computational cost of the integrated algorithm is compared with the cost of more traditional sequence of the wideband extension of the Side-Lobe Canceller and the focusing operation, to show the computational feasibility of the proposed integrated algorithm. The possibility to perform suboptimally the space-frequency adaptive nulling is also considered
Non-determinism in the Uptake of Gestural Information
No full textIt is well established that gestures and speech form an integrated system of communication; gestures that match the meaning of the speech they accompany favor the listener's discourse comprehension, whereas mismatching gestures whose meaning conveys information contradicting that conveyed by speech, impair comprehension. A less investigated issue is whether or not the uptake of gestural information is a deterministic process. In line with recent studies in the literature, we purport that the process may be modulated by certain factors. In particular, we investigate the role of unrelated gestures whose meaning, which is irrelevant to the speech they accompany, could be neglected. The results of four experiments led us to conclude that unrelated gestures are not processed, and that the uptake of gestural information is a non-deterministic process
Flipped classroom e social learning: il caso E-School
No full textThis article aims to illustrate a flipped classroom experimentation that took place in a high school in the city of Piacenza, in northern Italy. The “E-school” section has been activated in this school since 2013. This research began at the end of the second five-year period of the experimentation (2018/2019) with the aim of carrying out a first evaluation and returning a description that allows to highlight elements of interest and any critical issue with reference to four emerging dimensions:
● activelearningandinclassactivities;
● contentandaudiovisualpodcasts;
● autonomous learning, responsibility, evaluation;
● social learning and key competencies.
"The more you Gesture, the less I Gesture": co-speech gestures as a measure of mental model quality
No full textStudies in the literature have revealed that a speaker's co-speech gestures favor the construction of a complete and articulated mental model of the discourse by the listener; moreover, from the literature on co-speech gestures we know that they help the speaker to organize the stream of thought. Given these data, we hypothesized that a person who listens to a discourse accompanied by gestures would produce fewer co-speech gestures in recollecting the discourse compared to a person who listens to a discourse not accompanied by gestures. The analysis of the co-speech gestures produced by the participants in two experiments while recollecting the content of a discourse confirmed our predictions
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