Search results for "LESS"

Il monastero di Santa Caterina d’Alessandria di Palermo: conoscere per conservare

2019

Il saggio indaga il complesso monumentale di Santa Caterina d’Alessandria, di Palermo, che costituisce uno dei più antichi monasteri di clausura della città. Il contributo è il frutto della ricerca condotta da Renata Prescia e Rosario Scaduto e presentata nel catalogo della mostra Sacra et preziosa Orificeria dai monasteri di Palermo capitale, tenutasi nel Monastero di Santa Caterina d’Alessandria di Palermo, 28.12.2018-31.05.2019. Grazie alla convenzione sottoscritta dal Dipartimento di Architettura e la Soprintendenza per i Beni Culturali e Ambientali di Palermo è stato possibile effettuare un particolareggiato rilievo dello stato di conservazione del monumento e presentare dei progetti p…

Learning From Errors: Detecting Cross-Technology Interference in WiFi Networks

2018

In this paper, we show that inter-technology interference can be recognized using commodity WiFi devices by monitoring the statistics of receiver errors. Indeed, while for WiFi standard frames the error probability varies during the frame reception in different frame fields (PHY, MAC headers, and payloads) protected with heterogeneous coding, errors may appear randomly at any point during the time the demodulator is trying to receive an exogenous interfering signal. We thus detect and identify cross-technology interference on off-the-shelf WiFi cards by monitoring the sequence of receiver errors (bad PLCP, bad FCS, invalid headers, etc.) and propose two methods to recognize the source of in…

Evoluzione degli aromi varietali durante l’appassimento dell’uva Moscato d’Alessandria

2009

Using deep neural networks for kinematic analysis: Challenges and opportunities

2020

Kinematic analysis is often performed in a lab using optical cameras combined with reflective markers.\ud With the advent of artificial intelligence techniques such as deep neural networks, it is now possible\ud to perform such analyses without markers, making outdoor applications feasible. In this paper I summarise\ud 2D markerless approaches for estimating joint angles, highlighting their strengths and limitations.\ud In computer science, so-called ‘‘pose estimation” algorithms have existed for many years. These methods\ud involve training a neural network to detect features (e.g. anatomical landmarks) using a process called\ud supervised learning, which requires ‘‘training” images to be …

Viva voce: Voice and Voicelessness among Twelfth-Century Clerics

2015

Writing in his Summa on Gratian’s Decretum1 toward 1164, canonist Rufinus of Bologna2 evokes criminal prelates, saying, “vocem accusandi, reprehendi, docendi non habent” (they do not have a voice to accuse, punish, teach).3 Should this enumeration be understood as a commonplace statement about three possible functions of the voice, or should we suspect a set of deeper associations? Is Rufinus’s use of the word “voice” simply an alternative to other rhetorical or stylistic possibilities—such as the word “word” in particular—or is it truly a deliberate choice on the part of the canonist?

Multi-scale computational homogenization with applications to masonry structures

Enabling Retransmissions for Achieving Reliable Multicast Communications in WSNs

2016

To ensure end-to-end reliable multicast or broadcast transmissions in IEEE 802.15.4 based wireless sensor networks WSNs) is a challenging task since no retransmission and acknowledgment mechanisms are defined in such WSNs. In this paper, we propose three retransmission enabled multicast transmission schemes in order to achieve reliable packet transmissions in such networks. Different from the legacy CSMA/CA principle, these schemes allow a sending or forwarding node to retransmit a packet if necessary and enable implicit or/and explicit acknowledgment for multicast services. Simulations are performed in order to assess the performance of these schemes in terms of number of retransmissions, …

Priority-oriented multicast transmission schemes for heterogeneous traffic in WSNs

2016

To ensure quality of service (QoS) for heterogeneous traffic in IEEE 802.15.4 based wireless sensor networks (WSNs) is a challenging task since no traffic prioritization mechanism is defined in such WSNs. In this paper, we propose two priority-oriented multicast transmission schemes to provide QoS for heterogeneous traffic in WSNs. Contrary to the legacy CSMA/CA and FIFO principles, these schemes differentiate self-generated or received traffic and give priority to delay-sensitive traffic with respect to channel access and packet scheduling. Simulations are performed in order to assess the performance of these schemes in terms of end-to-end delay, energy consumption, packet delivery ratio, …

What's New for QoS in IEEE 802.11?

2013

Two amendments to IEEE 802.11 have recently been published: 802.11aa and 802.11ae. Both enhance Quality of Service (QoS) provisioning in Wi-Fi networks by providing support for multicast transmission, enhanced audio video streaming, coping with inter-network interference, and improved prioritization of management frames. The proposed solutions either extend mechanisms already existing in the standard or introduce new ones. Therefore, it is important for researchers to understand the new functionalities. To this end we provide the first description of these latest mechanisms: we present the motivation behind them, explain their design principles, provide examples of usage, and comment on com…

Evaluation and improvement of collective flooding in WSNs with various link correlations

2015

One of the main challenges confronted by wireless sensor networks (WSNs) is to reduce energy consumption of nodes for the purpose of network lifetime extension. In the literature, many backbone based protocols such as connected dominating set (CDS) and broadcast or multicast based protocols are employed in order to improve network performance in terms of metrics like energy consumption, number of transmissions and dissemination delay. In this paper, we evaluate the performance of a recently proposed transmission protocol known as collective flooding (CF), which is based on link correlation, under various link correlation conditions. Through simulations and analyses we demonstrate that altho…