Search results for "Model"
showing 10 items of 24058 documents
Numerical methods for a nonlinear impact model: A comparative study with closed-form corrections
2011
A physically based impact model-already known and exploited in the field of sound synthesis-is studied using both analytical tools and numerical simulations. It is shown that the Hamiltonian of a physical system composed of a mass impacting on a wall can be expressed analytically as a function of the mass velocity during contact. Moreover, an efficient and accurate approximation for the mass outbound velocity is presented, which allows to estimate the Hamiltonian at the end of the contact. Analytical results are then compared to numerical simulations obtained by discretizing the system with several numerical methods. It is shown that, for some regions of the parameter space, the trajectorie…
Reverberation still in business: Thickening and propagating micro-textures in physics-based sound modeling
2015
Artificial reverberation is usually introduced, as a digital audio effect, to give a sense of enclosing architectural space. In this paper we argue about the effectiveness and usefulness of diffusive reverberators in physically-inspired sound synthesis. Examples are given for the synthesis of textural sounds, as they emerge from solid mechanical interactions, as well as from aerodynamic and liquid phenomena.
Measuring the Task Induced Oscillatory Brain Activity Using Tensor Decomposition
2019
The characterization of dynamic electrophysiological brain activity, which form and dissolve in order to support ongoing cognitive function, is one of the most important goals in neuroscience. Here, we introduce a method with tensor decomposition for measuring the task-induced oscillations in the human brain using electroencephalography (EEG). The time frequency representation of source-reconstructed singletrail EEG data constructed a third-order tensor with three factors of time ∗ trails, frequency and source points. We then used a non-negative Canonical Polyadic decomposition (NCPD) to identify the temporal, spectral and spatial changes in electrophysiological brain activity. We validate …
The game of developing a game : hobbyist game developers as playful entrepreneurs in the Apple App Store
2015
The Industrial Applicability of PEA Space Charge Measurements, for Performance Optimization of HVDC Power Cables
2019
Cable manufacturing industries are constantly trying to improve the electrical performance of power cables. During the years, it was found that one of the most relevant degradation factors influencing the cable lifetime is the presence of space charge in the insulation layer. To detect the accumulated charge, the pulsed electro-acoustic (PEA) method is the most used technique. Despite the wide use of the PEA cell, several issues are still present. In particular, the PEA output signal is strongly disturbed by the acoustic waves reflections within the PEA cell. This causes the distortion of the output signal and therefore the misinterpretation of the charge profiles. This, in turn, may result…
Space-Time Forecasting of Seismic Events in Chile
2017
The aim of this work is to study the seismicity in Chile using the ETAS (epidemic type aftershock sequences) space‐time approach. The proposed ETAS model is estimated using a semi‐parametric technique taking into account the parametric and nonparametric components corresponding to the triggered and background seismicity, respectively. The model is then used to predict the temporal and spatial intensity of events for some areas of Chile where recent large earthquakes (with magnitude greater than 8.0 M) occurred.
Neighbourhood effects and determinants of population changes in Italy: a spatial perspective
2023
Population trends in Italy are strongly spatially differentiated, with some munic- ipalities showing a systematic loss of population, and others showing an equally continuous demographic increase. Here, we focus our attention on the spatial dimension of population change, looking at how different socio-economic and demographic dimensions affect population changes, as well as their spatial effects. After performing a preliminary descriptive analysis of the trends of population growth and decline in Italy over the last 40 years and the relevant demographic components, we used a spatial Durbin model (SDM) to investigate the potential existence of a diffusion process and the determinants of the…
THE EXPLORED ARCHITECTURE. THE VIRTUAL MODEL OF A HISTORICAL STRATIFICATION
2010
The present study deepens -through documents of historical iconography and critical studies on morphological, geometrical and structural aspects- spatial and volumetric relationships between the medieval Torre Pisana of Palazzo Reale to Palermo (also known as Palazzo dei Normanni) and the Astronomical Observatory, site on the summit of the tower. A brief historical and architectural description of the evolution of the tightly correlated structure to the historical-cultural vicissitudes, to the advancement of the scientific theories and to the innovation of the tools of observation and of survey, is a deepening of knowledge for the conservation and safeguard of the architectural testimony. T…
On the spatial configuration of scatterers for given delay-angle distributions
2014
Published version of an article in the journal: Engineering Letters. Also available from the publisher at: http://www.engineeringletters.com/issues_v22/issue_1/EL_22_1_05.pdf. Open access This paper investigates the distribution of scatterers located around the mobile station (MS) for given delay-angle distributions. The delay-angle distribution function represents the joint probability density function (PDF) of the time-ofarrival (TOA) and angle-of-arrival (AOA). Given such a joint PDF, we first derive a general expression for the distribution of the scatterers in both polar and Cartesian coordinates. We then analyze an important special case in which the TOA and the AOA follow the multipl…
Continuum: A spatiotemporal data model to represent and qualify filiation relationships
2013
International audience; This work introduces an ontology-based spatio-temporal data model to represent entities evolving in space and time. A dynamic phenomenon generates a complex relationship network between the entities involved in the process. At the abstract level, the relationships can be identity or topological filiations. The existence of an identity filiation depends on whether the object changes its identity or not. On the other hand, topological filiations are based exclusively on the spatial component, like in the case of growth, reduction, merging or splitting. When combining identity and topological filiations, six filiation relationships are obtained, forming a second abstrac…