2,763 research outputs found
Histogram of gradients of Time-Frequency Representations for Audio scene detection
This paper addresses the problem of audio scenes classification and
contributes to the state of the art by proposing a novel feature. We build this
feature by considering histogram of gradients (HOG) of time-frequency
representation of an audio scene. Contrarily to classical audio features like
MFCC, we make the hypothesis that histogram of gradients are able to encode
some relevant informations in a time-frequency {representation:} namely, the
local direction of variation (in time and frequency) of the signal spectral
power. In addition, in order to gain more invariance and robustness, histogram
of gradients are locally pooled. We have evaluated the relevance of {the novel
feature} by comparing its performances with state-of-the-art competitors, on
several datasets, including a novel one that we provide, as part of our
contribution. This dataset, that we make publicly available, involves
classes and contains about minutes of audio scene recording. We thus
believe that it may be the next standard dataset for evaluating audio scene
classification algorithms. Our comparison results clearly show that our
HOG-based features outperform its competitor
Flexible RDF data extraction from Wiktionary - Leveraging the power of community build linguistic wikis
We present a declarative approach implemented in a comprehensive opensource
framework (based on DBpedia) to extract lexical-semantic resources (an ontology about language use) from Wiktionary. The data currently includes language, part of speech, senses, definitions, synonyms, taxonomies (hyponyms, hyperonyms, synonyms, antonyms) and translations for each lexical word. Main focus is on flexibility to the loose schema and configurability towards differing language-editions ofWiktionary. This is achieved by a declarative mediator/wrapper approach. The goal is, to allow the addition of languages just by configuration without the need of programming, thus enabling the swift and resource-conserving adaptation of wrappers by domain experts. The extracted data is as fine granular as the source data in Wiktionary and additionally follows the lemon model. It enables use cases like disambiguation or machine translation. By offering a linked data service, we hope to extend DBpediaâs central role in the LOD infrastructure to the world of Open Linguistics.
Towards Commentary-Driven Soccer Player Analytics
Open information extraction (open IE) has been shown to be useful in a number of NLP Tasks, such as question answering, relation extraction, and information retrieval. Soccer is the most watched sport in the world. The dynamic nature of the game corresponds to the team strategy and individual contribution, which are the deciding factors for a teamâs success. Generally, companies collect sports event data manually and very rarely they allow free-access to these data by third parties. However, a large amount of data is available freely on various social media platforms where different types of users discuss these very events. To rely on expert data, we are currently using the live-match commentary as our rich and unexplored data-source.
Our aim out of this commentary analysis is to initially extract key events from each game and eventually key entities like players involved, player action and other player related attributes from these key events. We propose an end-to-end application to extract commentaries and extract player attributes from it. The study will primarily depend on an extensive crowd labelling of data involving precautionary periodical checks to prevent incorrectly tagged data. This research will contribute significantly towards analysis of commentary and acts as a cheap tool providing player performance analysis for smaller to intermediate budget soccer club
Development of sustainable tools (Database and software) for Marine Litter Data management
Entregable del proyecto CleanAtlanticEste entregable describe diversas herramientas de utilidad para la gestiĂłn de datos de basura marina
The Dictionary of Accessible Communication
Terminology on Accessible Communication has primarily evolved and been published within the borders of a given country with no or only little exchange across these borders. Since English can be regarded as the âlingua francaâ of science, this first GermanâEnglish dictionary of Accessible Communication will help to promote international exchange and an international discourse on this topic by attempting to define concepts that go beyond the scope of a single-country centered approach. The terminological work for this dictionary is based on the German Handbook of Accessible Communication. Most of the handbookâs contents are language-independent and applicable to other recipient communities. On the basis of the German terminology, the English equivalents, definitions and explanations were researched. The dictionary contributes to the development of a standardised terminology across languages and cultures
Packet analysis for network forensics: A comprehensive survey
Packet analysis is a primary traceback technique in network forensics, which, providing that the packet details captured are sufficiently detailed, can play back even the entire network traffic for a particular point in time. This can be used to find traces of nefarious online behavior, data breaches, unauthorized website access, malware infection, and intrusion attempts, and to reconstruct image files, documents, email attachments, etc. sent over the network. This paper is a comprehensive survey of the utilization of packet analysis, including deep packet inspection, in network forensics, and provides a review of AI-powered packet analysis methods with advanced network traffic classification and pattern identification capabilities. Considering that not all network information can be used in court, the types of digital evidence that might be admissible are detailed. The properties of both hardware appliances and packet analyzer software are reviewed from the perspective of their potential use in network forensics
Design of hardware architectures for HMMâbased signal processing systems with applications to advanced human-machine interfaces
In questa tesi viene proposto un nuovo approccio per lo sviluppo di interfacce uomoâmacchina. In particolare si
tratta il caso di sistemi di pattern recognition che fanno uso di Hidden Markov Models per la classificazione.
Il progetto di ricerca Ăš partito dallâideazione di nuove tecniche per la realizzazione di sistemi di riconoscimento
vocale per parlato spontaneo. Gli HMM sono stati scelti come lo strumento algoritmico di base per la realizzazione
del sistema. Dopo una fase di studio preliminare gli obiettivi sono stati estesi alla realizzazione di una architettura
hardware in grado di fornire uno strumento riconfigurabile che possa essere utilizzato non solo per il riconoscimento
vocale, ma in qualsiasi tipo di classificatore basato su HMM.
Il lavoro si concentra quindi sullo sviluppo di architetture hardware dedicate, ma nuovi risultati sono stati ottenuti
anche a livello di applicazione per quanto riguarda la classificazione di segnali elettroencefalografici attraverso
gli HMM.
Innanzitutto state sviluppata una architettura a livello di sistema applicabile a qualsiasi sistema di pattern
recognition che faccia usi di HMM. Lâarchitettura stata concepita in modo tale da essere utilizzabile come un
sistema standâalone. Definita lâarchitettura, un processore hardware per HMM, completamente riconfigurabile,
stato decritto in linguaggio VHDL e simulato con successo. Un array parallelo di questi processori costituisce di
fatto il nucleo di processamento dellâarchitettura sviluppata.
Sulla base del progetto in VHDL, due piattaforme di prototipaggio rapido basate su FPGA sono state selezionate
per dei test di implementazione. Diverse configurazioni costituite da array paralleli di processori HMM sono state
implementate su FPGA. Le soluzioni che offrivano un miglior compromesso tra prestazioni e quantitĂ di risorse
hardware utilizzate sono state selezionate per ulteriori analisi.
Un sistema software per il pattern recognition basato su HMM stato scelto come sistema di riferimento per
verificare la corretta funzionalitĂ delle architetture implementate. Diversi test sono stati progettati per validare che
il funzionamento del sistema corrispondesse alle specifiche iniziali. Le versioni implementate del sistema sono state
confrontate con il software di riferimento sulla base dei risultati forniti dai test. Dal confronto Ăš stato possibile
appurare che le architetture sviluppate hanno un comportamento corrispondente a quello richiesto.
Infine le implementazioni dellâarray parallelo di processori HMM `e sono state applicate a due applicazioni reali:
un riconoscitore vocale, ed un classificatore per interfacce basate su segnali elettroencefalografici. In entrambi i
casi lâarchitettura si Ăš dimostrata in grado di gestire lâapplicazione senza alcun problema. Lâuso del processamento
hardware per il riconoscimento vocale apre di fatto la strada a nuovi sviluppi nel campo grazie al notevole incremento
di prestazioni ottenibili in termini di tempo di esecuzione. Lâapplicazione al processamento dellâEEG, invece,
introduce di fatto un approccio completamente nuovo alla classificazione di questo tipo di segnali, e mostra come in
futuro potrebbe essere possibile lo sviluppo di interfacce basate sulla classificazione dei segnali generati dal pensiero
spontaneo.
I possibili sviluppi del lavoro iniziato con questa tesi sono molteplici. Una direzione possibile Ăš quella dellâimplementazione
completa dellâarchitettura proposta come un sistema standâalone riconfigurabile per lâaccelerazione
di sistemi per pattern recognition di qualsiasi natura purchĂš basati su HMM. Le potenzialitĂ di tale sistema renderebbero
possibile la realizzazione di classificatiori in tempo reale con un alto grado di complessitĂ , e quindi allo
sviluppo di interfacce realmente multimodali, con una vasta gamma di applicazioni, dai sistemi di per lo spazio a
quelli di supporto per persone disabili.In this thesis a new approach is described for the development of humanâcomputer interfaces. In particular
the case of pattern recognition systems based on Hidden Markov Models have been taken into account.
The research started from he development of techniques for the realization of natural language speech
recognition systems. The Hidden Markov Model (HMM) was chosen as the main algorithmic tool to be
used to build the system. After the early work the goal was extended to the development of an hardware
architecture that provided a reconfigurable tool to be used in any pattern recognition task, and not only in
speech recognition.
The whole work is thus focused on the development of dedicated hardware architectures, but also some
new results have been obtained on the classification of electroencephalographic signals through the use of
HMMs.
Firstly a systemâlevel architecture has been developed to be used in HMM based pattern recognition
systems. The architecture has been conceived in order to be able to work as a standâalone system. Then a
VHDL description has been made of a flexible and completely reconfigurable hardware HMM processor and
the design was successfully simulated. A parallel array of these processors is actually the core processing
block of the developed architecture.
Then two suitable FPGA based, fast prototyping platforms have been identified to be the targets for
the implementation tests. Different configurations of parallel HMM processor arrays have been set up and
mapped on the target FPGAs. Some solutions have been selected to be the best in terms of balance between
performance and resources utilization.
Furthermore a software HMM based pattern recognition system has been chosen to be the reference system
for the functionality of the implemented subsystems. A set of tests have been developed with the aim to test
the correct functionality of the hardware. The implemented system was compared to the reference system
on the basis of the testsâ results, and it was found that the behavior was the one expected and the required
functionality was correctly achieved.
Finally the implementation of the parallel HMM array was tested through its application to two realâworld
applications: a speech recognition task and a brainâcomputer interface task. In both cases the architecture
showed to be functionally suitable and powerful enough to handle the task without problems. The application
of the hardware processing to speech recognition opens new perspectives in the design of this kind of systems
because of the dramatic increment in performance. The application to brainâcomputer interface is really
interesting because of a new approach in the classification of EEG that shows how could be possible a future
development of interfaces based on the classification of spontaneous thought.
The possible evolution directions of the work started with this thesis are many. Effort could be spent of
the implementation of the developed architecture as a standâalone reconfigurable system suitable for any kind
of HMMâbased pattern recognition task. The potential performance of such a system could open the way
to extremely complex realâtime pattern recognition systems, and thus to the realization of truly multimodal
interfaces, with a variety of applications, from space to aid systems for the impaired
A Distributed Ledger based infrastructure for Intelligent Transportation Systems
Intelligent Transportation Systems (ITS) are proposed as an efficient way to improve performances in transportation systems applying information, communication, and sensor technologies to vehicles and transportation infrastructures. The great amount of vehicles produced data, indeed, can potentially lead to a revolution in ITS development, making them more powerful multifunctional systems. To this purpose, the use of Vehicular Ad-hoc Networks (VANETs) can provide comfort and security to drivers through reliable communications. Meanwhile, distributed ledgers have emerged in recent years radically evolving the way that we used to consider finance, trust in communication and even renewing the concept of data sharing and allowing to establish autonomous, secured, trusted and decentralized systems. In this work an ITS infrastructure based on the combination of different emerging Distributed Ledger Technologies (DLTs) and VANETs is proposed, resulting in a transparent, self-managed and self-regulated system, that is not fully managed by a central authority. The intended design is focused on the user ability to use any type of DLT-based application and to transact using Smart Contracts, but also on the access control and verification over userâs vehicle produced data. Users "smart" transactions are achieved thanks to the Ethereum blockchain, widely used for distributed trusted computation, whilst data sharing and data access is possible thanks to the use of IOTA, a DLT fully designed to operate in the Internet of Things landscape, and IPFS, a protocol and a network that allows to work in a distributed file system. The aim of this thesis is to create a ready-to-work infrastructure based on the hypothesis that every user in the ITS must be able to participate. To evaluate the proposal, an infrastructure implementation is used in different real world use cases, common in Smart Cities and related to the ITS, and performance measurements are carried out for DLTs used
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