4,490 research outputs found
Pain-Inspired Intrinsic Reward For Deep Reinforcement Learning
abstract: Reinforcement learning (RL) is a powerful methodology for teaching autonomous agents complex behaviors and skills. A critical component in most RL algorithms is the reward function -- a mathematical function that provides numerical estimates for desirable and undesirable states. Typically, the reward function must be hand-designed by a human expert and, as a result, the scope of a robot's autonomy and ability to safely explore and learn in new and unforeseen environments is constrained by the specifics of the designed reward function. In this thesis, I design and implement a stateful collision anticipation model with powerful predictive capability based upon my research of sequential data modeling and modern recurrent neural networks. I also develop deep reinforcement learning methods whose rewards are generated by self-supervised training and intrinsic signals. The main objective is to work towards the development of resilient robots that can learn to anticipate and avoid damaging interactions by combining visual and proprioceptive cues from internal sensors. The introduced solutions are inspired by pain pathways in humans and animals, because such pathways are known to guide decision-making processes and promote self-preservation. A new "robot dodge ball' benchmark is introduced in order to test the validity of the developed algorithms in dynamic environments.Dissertation/ThesisMasters Thesis Computer Science 201
Densely connected GCN model for motion prediction
© 2020 The Authors. Computer Animation and Virtual Worlds published by John Wiley & Sons, Ltd. Human motion prediction is a fundamental problem in understanding human natural movements. This task is very challenging due to the complex human body constraints and diversity of action types. Due to the human body being a natural graph, graph convolutional network (GCN)-based models perform better than the traditional recurrent neural network (RNN)-based models on modeling the natural spatial and temporal dependencies lying in the motion data. In this paper, we develop the GCN-based models further by adding densely connected links to increase their feature utilizations and address oversmoothing problem. More specifically, the GCN block is used to learn the spatial relationships between the nodes and each feature map of the GCN block propagates directly to every following block as input rather than residual linked. In this way, the spatial dependency of human motion data is exploited more sufficiently and the features of different level of scale are fused more efficiently. Extensive experiments demonstrate our model achieving the state-of-the-art results on CMU dataset
Modeling competition between two pharmaceutical drugs using innovation diffusion models
The study of competition among brands in a common category is an interesting
strategic issue for involved firms. Sales monitoring and prediction of
competitors' performance represent relevant tools for management. In the
pharmaceutical market, the diffusion of product knowledge plays a special role,
different from the role it plays in other competing fields. This latent feature
naturally affects the evolution of drugs' performances in terms of the number
of packages sold. In this paper, we propose an innovation diffusion model that
takes the spread of knowledge into account. We are motivated by the need of
modeling competition of two antidiabetic drugs in the Italian market.Comment: Published at http://dx.doi.org/10.1214/15-AOAS868 in the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Semantic guided multi-future human motion prediction
L'obiettivo della tesi è quello di esplorare il possibile utilizzo di un modello basato su reti neurali già sviluppato per la previsione multi-futuro del moto di un agente umano. Data una traiettoria con informazione spaziale (sotto forma di angoli relativi dei giunti) di una struttura semplificata di scheletro umano, si cerca di aumentare l'accuratezza di previsione del modello grazie all'aggiunta di informazione semantica. Per informazione semantica si intende il significato ad alto livello dell'azione che l'agente umano sta compiendo.Investigate the potential utilization of a pre-existing neural network model, originally designed for multi-future prediction of human agent motion in a static camera scene, adapted to forecast rotational trajectories of human joints. By incorporating semantic information, pertaining to the higher-level depiction of the human agent's action, the objective is to enhance the prediction accuracy of the model. The study made use of the AMASS and BABEL datasets to achieve this purpose
Survey on video anomaly detection in dynamic scenes with moving cameras
The increasing popularity of compact and inexpensive cameras, e.g.~dash
cameras, body cameras, and cameras equipped on robots, has sparked a growing
interest in detecting anomalies within dynamic scenes recorded by moving
cameras. However, existing reviews primarily concentrate on Video Anomaly
Detection (VAD) methods assuming static cameras. The VAD literature with moving
cameras remains fragmented, lacking comprehensive reviews to date. To address
this gap, we endeavor to present the first comprehensive survey on Moving
Camera Video Anomaly Detection (MC-VAD). We delve into the research papers
related to MC-VAD, critically assessing their limitations and highlighting
associated challenges. Our exploration encompasses three application domains:
security, urban transportation, and marine environments, which in turn cover
six specific tasks. We compile an extensive list of 25 publicly-available
datasets spanning four distinct environments: underwater, water surface,
ground, and aerial. We summarize the types of anomalies these datasets
correspond to or contain, and present five main categories of approaches for
detecting such anomalies. Lastly, we identify future research directions and
discuss novel contributions that could advance the field of MC-VAD. With this
survey, we aim to offer a valuable reference for researchers and practitioners
striving to develop and advance state-of-the-art MC-VAD methods.Comment: Under revie
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