4,376 research outputs found
Rossini e il sublime: qualche spunto di riflessione/Rossini und das Erhabene: einige Denkanstoße
No full textNell’epoca della fulminea ascesa e affermazione europea di Rossini, così come nel momento culminante del Romanticismo, quando ancora le sue opere sono presenti nella vita musicale di molti centri del continente, una questione che traspare, in modo al tempo stesso evidente e ambiguo, nel dibattito che anima la recezione della musica rossiniana, è il rapporto di quest’ultima con il principio del sublime. Su questo aspetto, che si staglia sullo sfondo della complessa e problematica accoglienza delle opere di Rossini nell’area germanofona, si può forse ancora tornare con profitto anche in sede di riflessione storiografica. Cercherò di sviluppare qualche spunto rilevante in questo senso, concentrandomi essenzialmente sulle caratteristiche sonore e sull’orientamento comunicativo di alcuni brani rossiniani, in riferimento soprattutto al rapporto tra musica e rappresentazione. L’obbiettivo è contribuire al chiarimento di un tratto saliente, ma spesso travisato e facilmente travisabile dell’espressione in Rossini, centrale per comprendere anche il tratto di modernità della sua musica
Rossini - Beethoven: un conflitto d'interessi; Rossini - Beethoven: Ein Interessenkonflikt
No full textOffline and Online Planning and Control Strategies for the Multi-Contact and Biped Locomotion of Humanoid Robots
No full textIn the past decades, the Research on humanoid robots made progress forward accomplishing exceptionally dynamic and agile motions. Starting from the DARPA Robotic Challenge in 2015, humanoid platforms have been successfully employed to perform more and more challenging tasks with the eventual aim of assisting or replacing humans in hazardous and stressful working situations. However, the deployment of these complex machines in realistic domestic and working environments still represents a high-level challenge for robotics. Such environments are characterized by unstructured and cluttered settings with continuously varying conditions due to the dynamic presence of humans and other mobile entities, which cannot only compromise the operation of the robotic system but can also pose severe risks both to the people and the robot itself due to unexpected interactions and impacts. The ability to react to these unexpected interactions is therefore a paramount requirement for enabling the robot to adapt its behavior to the task needs and the characteristics of the environment. Further, the capability to move in a complex and varying environment is an essential skill for a humanoid robot for the execution of any task. Indeed, human instructions may often require the robot to move and reach a desired location, e.g., for bringing an object or for inspecting a specific place of an infrastructure. In this context, a flexible and autonomous walking behavior is an essential skill, study of which represents one of the main topics of this Thesis, considering disturbances and unfeasibilities coming both from the environment and dynamic obstacles that populate realistic scenarios.
Locomotion planning strategies are still an open theme in the humanoids and legged robots research and can be classified in sample-based and optimization-based planning algorithms. The first, explore the configuration space, finding a feasible path between the start and goal robot’s configuration with different logic depending on the algorithm. They suffer of a high computational cost that often makes difficult, if not impossible, their online implementations but, compared to their counterparts, they do not need any environment or robot simplification to find a solution and they are probabilistic complete, meaning that a feasible solution can be certainly found if at least one exists. The goal of this thesis is to merge the two algorithms in a coupled offline-online planning framework to generate an offline global trajectory with a sample-based approach to cope with any kind of cluttered and complex environment, and online locally refine it during the execution, using a faster optimization-based algorithm that more suits an online implementation. The offline planner performances are improved by planning in the robot contact space instead of the whole-body robot configuration space, requiring an algorithm that maps the two state spaces.
The framework proposes a methodology to generate whole-body trajectories for the motion of humanoid and legged robots in realistic and dynamically changing environments.
This thesis focuses on the design and test of each component of this planning framework, whose validation is carried out on the real robotic platforms CENTAURO and COMAN+ in various loco-manipulation tasks scenarios.  
Resting state cortical electroencephalographic rhythms in covert hepatic encephalopathy and Alzheimer's disease
Full text linkPatients suffering from prodromal (i.e., amnestic mild cognitive impairment, aMCI) and overt Alzheimer's disease (AD) show abnormal cortical sources of resting state electroencephalographic (EEG) rhythms. Here we tested the hypothesis that these sources show extensive abnormalities in liver cirrhosis (LC) patients with a cognitive impairment due to covert and diffuse hepatic encephalopathy (CHE). EEG activity was recorded in 64 LC (including 21 CHE), 21 aMCI, 21 AD, and 21 cognitively intact (Nold) subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. Widespread sources of theta (all but frontal), alpha 1 (all but occipital), and alpha 2 (parietal, temporal) rhythms were higher in amplitude in all LC patients than in the Nold subjects. In these LC patients, the activity of central, parietal, and temporal theta sources correlated negatively, and parietal and temporal alpha 2 sources correlated positively with an index of global cognitive status. Finally, widespread theta (all but frontal) and alpha 1 (all but occipital) sources showed higher activity in the sub-group of LC patients with CHE than in the patients with aMCI or AD. These results unveiled the larger spatial-frequency abnormalities of the resting state EEG sources in the CHE compared to the AD condition
Bayesian semiparametric inference for TVP-SVAR models with asymmetry and fat tails
No full textTime-varying parameter (TVP) structural vector autoregressive models with stochastic volatility (SVAR-SV) usually assume Gaussian innovations and a smooth or discrete path for the coefficients. To account for possible skewness and fat tails, this work introduces a semiparametric mixture of multivariate restricted skew-t innovation distributions, also permitting the inference of clusters of asymmetry across data series. Moreover, a dynamic shrinkage prior is designed for the coefficients of the contemporaneous and lagged variables to model the path of the parameters flexibly. Inference in high-dimensional settings is performed via a Markov chain Monte Carlo algorithm that leverages the stochastic representation of the skew-t distribution for obtaining a conditional linear Gaussian state-space model. Then, the algorithm alternates between the centred and non-centred parametrizations to improve the mixing and samples from the joint smoothed distribution without loops. The proposed semiparametric approach is combined with a sparsification method to extract time-varying Granger-causal networks in different applications regarding the COVID-19 pandemic across Europe and financial contagion transmission in Europe and the world
An assessment of the impact of possible CAP reform scenarios on Romanian agriculture
Full text linkUsing a simplified model, with key-variable the prices of two different possible scenarios of CAP reform after 2013 (moderate and radical), this paper present a comparison between the price effects of implementation of each reform scenario at 2015 horizon on Romanian agriculture. This short analysis shows that, under the presented hypotheses, the net welfare effect, due to the price changes, for the selected products, is positive in both reform scenarios, yet greater in the case of the radical reform. Integrated in the large context of Romanian development, it seems that the influence of CAP reform upon agriculture and rural areas will be most likely a gradual one: an interpenetration between the two scenarios is foreseeable, starting with the moderate reform that will dominate the period around 2013, the reform measures acquiring a more radical character afterwards.CAP reform, Romania, welfare effects, Agricultural and Food Policy,
Financing flexibility: The case of outsourcing
Full text linkWe investigate the relationship between the extent and timing of vertical flexibility and the financial choices of a firm. By vertical flexibility we mean partial/total and reversible outsourcing of a necessary input. A firm simultaneously selects the vertical setting and the financial sources of investment in flexibility, in particular debt and venture capital. A loan may come from a lender that requires the payment of a fixed coupon over time and an option to buy out the firm in certain circumstances. Debt leads to the same level of flexibility of an unlevered firm. Yet investment occurs earlier. The injection of venture capital reduces the quest for vertical flexibility and speeds up investment. Then, there arises a fresh substitutability between a financial (venture capital) and a real variable (vertical flexibility)
Flexible and objective time series analysis: a loss-based approach with two-piece location-scale distributions
No full textTwo-piece location-scale models are used for modeling data presenting\ud
departures from symmetry. In this paper, we propose an objective Bayesian\ud
methodology for the tail parameter of two particular distributions of the above\ud
family: the skewed exponential power distribution and the skewed generalised\ud
logistic distribution. We apply the proposed objective approach to time series\ud
models and linear regression models where the error terms follow the\ud
distributions object of study. The performance of the proposed approach is\ud
illustrated through simulation experiments and real data analysis. The\ud
methodology yields improvements in density forecasts, as shown by the analysis\ud
we carry out on the electricity prices in Nordpool markets
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