Modeling Interacting Time-Series Signals

Many real-life systems consist of multiple information signals which might be potentially interacting with each other over time. These interactions can be estimated/modeled using techniques like Pearson Correlation (PC), Time lagged Cross Correlation (TLCC) and windowed TLCC, Dynamic Time Warping (DTW), and coupled Hidden Markov Model (cHMM). These techniques, excluding cHMM, cannot capture non-linear interactions and does not work well with multi-variate data. Although cHMM can capture the interactions effectively, it is bound by Markov property and other assumptions like latent variables, prior distributions, etc. These influence the performance of the model significantly. Recurrent Neural Network (RNN) is a variant of Neural Networks which can be used to model time-series data. RNN based architectures are the new state-of-the-art for complex tasks like machine translation. In this research, we explore techniques to extend RNNs to model interacting time-series signals. We propose architectures with coupling and attention mechanism. We evaluate the performance of the models on synthetically generated and real-life data sets. We compare the performance of our proposed architectures to similar ones in the literature. The goal of this exercise is to determine the most effective architecture to capture interaction information in the given interrelated time-series signals

Reactive Video:Adaptive Video Playback Based on User Motion for Supporting Physical Activity

Videos are a convenient platform to begin, maintain, or improve a ftness program or physical activity. Traditional video systems allow users to manipulate videos through specifc user interface actions such as button clicks or mouse drags, but have no model of what the user is doing and are unable to adapt in useful ways. We present adaptive video playback, which seamlessly synchronises video playback with the user’s movements, building upon the principle of direct manipulation video navigation. We implement adaptive video playback in Reactive Video, a vision-based system which supports users learning or practising a physical skill. The use of pre-existing videos removes the need to create bespoke content or specially authored videos, and the system can provide real-time guidance and feedback to better support users when learning new movements. Adaptive video playback using a discrete Bayes and particle flter are evaluated on a data set collected of participants performing tai chi and radio exercises. Results show that both approaches can accurately adapt to the user’s movements, however reversing playback can be problematic

A Survey of Deep Learning in Sports Applications: Perception, Comprehension, and Decision

Deep learning has the potential to revolutionize sports performance, with applications ranging from perception and comprehension to decision. This paper presents a comprehensive survey of deep learning in sports performance, focusing on three main aspects: algorithms, datasets and virtual environments, and challenges. Firstly, we discuss the hierarchical structure of deep learning algorithms in sports performance which includes perception, comprehension and decision while comparing their strengths and weaknesses. Secondly, we list widely used existing datasets in sports and highlight their characteristics and limitations. Finally, we summarize current challenges and point out future trends of deep learning in sports. Our survey provides valuable reference material for researchers interested in deep learning in sports applications

Multikernel convolutional neural network for sEMG based hand gesture classification

openIl riconoscimento dei gesti della mano è un argomento ampiamente discusso in letteratura, dove vengono analizzate diverse tecniche sia in termini di tipi di segnale in ingresso che di algoritmi. Tra i più utilizzati ci sono i segnali elettromiografici (sEMG), già ampiamente sfruttati nelle applicazioni di interazione uomo-macchina (HMI). Determinare come decodificare le informazioni contenute nei segnali EMG in modo robusto e accurato è un problema chiave per il quale è urgente trovare una soluzione. Recentemente, molti incarichi di riconoscimento dei pattern EMG sono stati affrontati utilizzando metodi di deep learning. Nonostante le elevate prestazioni di questi ultimi, le loro capacità di generalizzazione sono spesso limitate dall'elevata eterogeneità tra i soggetti, l'impedenza cutanea, il posizionamento dei sensori, ecc. Inoltre, poiché questo progetto è focalizzato sull'applicazione in tempo reale di protesi, ci sono maggiori vincoli sui tempi di risposta del sistema che riducono la complessità dei modelli. In questa tesi è stata testata una rete neurale convoluzionale multi-kernel su diversi dataset pubblici per verificare la sua generalizzabilità. Inoltre, è stata analizzata la capacità del modello di superare i limiti inter-soggetto e inter-sessione in giorni diversi, preservando i vincoli legati a un sistema embedded. I risultati confermano le difficoltà incontrate nell'estrazione di informazioni dai segnali emg; tuttavia, dimostrano la possibilità di ottenere buone prestazioni per un uso robusto di mani prostetiche. Inoltre, è possibile ottenere prestazioni migliori personalizzando il modello con tecniche di transfer learning e di adattamento al dominio.Hand gesture recognition is a widely discussed topic in the literature, where different techniques are analyzed in terms of both input signal types and algorithms. Among the most widely used are electromyographic signals (sEMG), which are already widely exploited in human-computer interaction (HMI) applications. Determining how to decode the information contained in EMG signals robustly and accurately is a key problem for which a solution is urgently needed. Recently, many EMG pattern recognition tasks have been addressed using deep learning methods. Despite their high performance, their generalization capabilities are often limited by high heterogeneity among subjects, skin impedance, sensor placement, etc. In addition, because this project is focused on the real-time application of prostheses, there are greater constraints on the system response times that reduce the complexity of the models. In this thesis, a multi-kernel convolutional neural network was tested on several public datasets to verify its generalizability. In addition, the model's ability to overcome inter-subject and inter-session constraints on different days while preserving the constraints associated with an embedded system was analyzed. The results confirm the difficulties encountered in extracting information from emg signals; however, they demonstrate the possibility of achieving good performance for robust use of prosthetic hands. In addition, better performance can be achieved by customizing the model with transfer learning and domain-adaptationtechniques

A Politics of Intellectual Property: Environmentalism for the Net?

This Essay argues that we need a politics, or perhaps a political economy, of intellectual property. Using the controversy over copyright on the Internet as a case study and the history of the environmental movement as a comparison, it offers a couple of modest proposals about what such a politics might look like-- what theoretical ideas it might draw upon, and what constituencies it might unite

Using deep learning for food recognition

Treballs Finals de Grau d'Enginyeria Informàtica, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2020, Director: Petia Radeva i Bhalaji Nagarajan[en] Image recognition is a very challenging and important problem in the computer vision field. And food image classification is one of the most challenging branches of this field. In real-world scenarios, it is more common for a food image to have more than one food item. As a result, the multi-label classification problem has generated significant interest in recent years. However, multi-label recognition is a much more difficult object recognition task compared to single-label recognition. In this work, we will study the multi-label food recognition problem by using deep learning algorithms, specifically Convolutional Neural Networks. We will show how redefining the loss function as well as augmenting the training dataset can leverage the multi-label food recognition problem. Extensive validation will be presented to show the strengths and limitations of multi-label food recognition