Search results for "CODE"

DESIGN ZINGARO. Un'esperienza di progettazione e didattica partecipata presso la Riserva Naturale Orientata “Zingaro”. Creazioni di Land Art e Design…

2009

Formazione e sostenibilità: didattica partecipata e aree protette, arte dell'intreccio e ecodesign

2009

A multidimensional hydrodynamic code for structure evolution in cosmology

1996

A cosmological multidimensional hydrodynamic code is described and tested. This code is based on modern high-resolution shock-capturing techniques. It can make use of a linear or a parabolic cell reconstruction as well as an approximate Riemann solver. The code has been specifically designed for cosmological applications. Two tests including shocks have been considered: the first one is a standard shock tube and the second test involves a spherically symmetric shock. Various additional cosmological tests are also presented. In this way, the performance of the code is proved. The usefulness of the code is discussed; in particular, this powerful tool is expected to be useful in order to study…

3-Dimensional Hydrodynamic Interaction of a Supernova Remnant Shock with an Isolated Cloud

2006

We report on a computational key-project in astrophysics. The project is aimed at studying the interaction of a supernova shock wave with interstellar clouds. We describe the numerical code used, namely FLASH, a multi-dimensional astrophysical hydrodynamics code for parallel computers developed at the FLASH center (The University of Chicago); our team collaborates with, and contributes to, the FLASH project. We discuss the resources required for the whole project, the I/O management, the performance and the scalability of the code on IBM/Sp4 at CINECA. Finally, we present a selection of results. © 2005 IEEE.

A Configuration of 3-phase Traction Inverter Employing {SiC} Devices

2022

In the scenario of a more and more sustainable society, an increasing electrification in different fields, such as mobility and industrial applications, is foreseen in the next decades. As far as power electronics is concerned, a challenging perspective is represented by achieving higher and higher switching frequencies while maintaining high voltage and low power losses. To do that, emerging semiconductor technologies are supposed to be increasingly employed, as well as innovative topologies of connections among switching devices. Among them, the cascode configuration can notably contribute to achieve high levels of dV/dt without losing efficiency. In this paper, a 3-phase Pulse Width Modu…

Deep Completion Autoencoders for Radio Map Estimation

2022

Radio maps provide metrics such as power spectral density for every location in a geographic area and find numerous applications such as UAV communications, interference control, spectrum management, resource allocation, and network planning to name a few. Radio maps are constructed from measurements collected by spectrum sensors distributed across space. Since radio maps are complicated functions of the spatial coordinates due to the nature of electromagnetic wave propagation, model-free approaches are strongly motivated. Nevertheless, all existing schemes for radio occupancy map estimation rely on interpolation algorithms unable to learn from experience. In contrast, this paper proposes a…

Rapid parameter estimation of discrete decaying signals using autoencoder networks

2021

Machine learning: science and technology 2(4), 045024 (2021). doi:10.1088/2632-2153/ac1eea

Fast Channel Estimation in the Transformed Spatial Domain for Analog Millimeter Wave Systems

2021

Fast channel estimation in millimeter-wave (mmWave) systems is a fundamental enabler of high-gain beamforming, which boosts coverage and capacity. The channel estimation stage typically involves an initial beam training process where a subset of the possible beam directions at the transmitter and receiver is scanned along a predefined codebook. Unfortunately, the high number of transmit and receive antennas deployed in mmWave systems increase the complexity of the beam selection and channel estimation tasks. In this work, we tackle the channel estimation problem in analog systems from a different perspective than used by previous works. In particular, we propose to move the channel estimati…

Secrecy analysis and learning-based optimization of cooperative NOMA SWIPT systems

2019

Non-orthogonal multiple access (NOMA) is considered to be one of the best candidates for future networks due to its ability to serve multiple users using the same resource block. Although early studies have focused on transmission reliability and energy efficiency, recent works are considering cooperation among the nodes. The cooperative NOMA techniques allow the user with a better channel (near user) to act as a relay between the source and the user experiencing poor channel (far user). This paper considers the link security aspect of energy harvesting cooperative NOMA users. In particular, the near user applies the decode-and-forward (DF) protocol for relaying the message of the source no…

Design of SCMA Codebooks using Differential Evolution

2020

Non-orthogonal multiple access (NOMA) is a promising technology which meets the demands of massive connectivity in future wireless networks. Sparse code multiple access (SCMA) is a popular code-domain NOMA technique. The effectiveness of SCMA comes from: (1) the multi-dimensional sparse codebooks offering high shaping gain and (2) sophisticated multi-user detection based on message passing algorithm (MPA). The codebooks of the users play the main role in determining the performance of SCMA system. This paper presents a framework to design the codebooks by taking into account the entire system including the SCMA encoder and the MPA-based detector. The symbol-error rate (SER) is considered as…