In recent years, unmanned aerial vehicle (UAV) related technology has expanded knowledge in the area, bringing to light new problems and challenges that require solutions. Furthermore, because the technology allows processes usually carried out by people to be automated, it is in great demand in industrial sectors. The automation of these vehicles has been addressed in the literature, applying different machine learning strategies. Reinforcement learning (RL) is an automation framework that is frequently used to train autonomous agents. RL is a machine learning paradigm wherein an agent interacts with an environment to solve a given task. However, learning autonomously can be time consuming, computationally expensive, and may not be practical in highly-complex scenarios. Interactive reinforcement learning allows an external trainer to provide advice to an agent while it is learning a task. In this study, we set out to teach an RL agent to control a drone using reward-shaping and policy-shaping techniques simultaneously. Two simulated scenarios were proposed for the training; one without obstacles and one with obstacles. We also studied the influence of each technique. The results show that an agent trained simultaneously with both techniques obtains a lower reward than an agent trained using only a policy-based approach. Nevertheless, the agent achieves lower execution times and less dispersion during training.

Detecting anomalous data within time series is a very relevant task in pattern recognition and machine learning, with many possible applications that range from disease prevention in medicine, e.g., detecting early alterations of the health status before it can clearly be defined as "illness" up to monitoring industrial plants. Regarding this latter application, detecting anomalies in an industrial plant's status firstly prevents serious damages that would require a long interruption of the production process. Secondly, it permits optimal scheduling of maintenance interventions by limiting them to urgent situations. At the same time, they typically follow a fixed prudential schedule according to which components are substituted well before the end of their expected lifetime. This paper describes a case study regarding the monitoring of the status of Laser-guided Vehicles (LGVs) batteries, on which we worked as our contribution to project SUPER (Supercomputing Unified Platform, Emilia Romagna) aimed at establishing and demonstrating a regional High-Performance Computing platform that is going to represent the main Italian supercomputing environment for both computing power and data volume.

The broad usage of mobile devices nowadays, the sensitiveness of the information contained in them, and the shortcomings of current mobile user authentication methods are calling for novel, secure, and unobtrusive solutions to verify the users' identity. In this article, we propose TypeFormer, a novel Transformer architecture to model free-text keystroke dynamics performed on mobile devices for the purpose of user authentication. The proposed model consists in Temporal and Channel Modules enclosing two Long Short-Term Memory (LSTM) recurrent layers, Gaussian Range Encoding (GRE), a multi-head Self-Attention mechanism, and a Block-Recurrent structure. Experimenting on one of the largest public databases to date, the Aalto mobile keystroke database, TypeFormer outperforms current state-of-the-art systems achieving Equal Error Rate (EER) values of 3.25% using only 5 enrolment sessions of 50 keystrokes each. In such way, we contribute to reducing the traditional performance gap of the challenging mobile free-text scenario with respect to its desktop and fixed-text counterparts. Additionally, we analyse the behaviour of the model with different experimental configurations such as the length of the keystroke sequences and the amount of enrolment sessions, showing margin for improvement with more enrolment data. Finally, a cross-database evaluation is carried out, demonstrating the robustness of the features extracted by TypeFormer in comparison with existing approaches.

The detection and prevention of illegal fishing is critical to maintaining a healthy and functional ecosystem. Recent research on ship detection in satellite imagery has focused exclusively on performance improvements, disregarding detection efficiency. However, the speed and compute cost of vessel detection are essential for a timely intervention to prevent illegal fishing. Therefore, we investigated optimization methods that lower detection time and cost with minimal performance loss. We trained an object detection model based on a convolutional neural network (CNN) using a dataset of satellite images. Then, we designed two efficiency optimizations that can be applied to the base CNN or any other base model. The optimizations consist of a fast, cheap classification model and a statistical algorithm. The integration of the optimizations with the object detection model leads to a trade-off between speed and performance. We studied the trade-off using metrics that give different weight to execution time and performance. We show that by using a classification model the average precision of the detection model can be approximated to 99.5% in 44% of the time or to 92.7% in 25% of the time.

A tractogram is a virtual representation of the brain white matter. It is composed of millions of virtual fibers, encoded as 3D polylines, which approximate the white matter axonal pathways. To date, tractograms are the most accurate white matter representation and thus are used for tasks like presurgical planning and investigations of neuroplasticity, brain disorders, or brain networks. However, it is a well-known issue that a large portion of tractogram fibers is not anatomically plausible and can be considered artifacts of the tracking procedure. With Verifyber, we tackle the problem of filtering out such non-plausible fibers using a novel fully-supervised learning approach. Differently from other approaches based on signal reconstruction and/or brain topology regularization, we guide our method with the existing anatomical knowledge of the white matter. Using tractograms annotated according to anatomical principles, we train our model, Verifyber, to classify fibers as either anatomically plausible or non-plausible. The proposed Verifyber model is an original Geometric Deep Learning method that can deal with variable size fibers, while being invariant to fiber orientation. Our model considers each fiber as a graph of points, and by learning features of the edges between consecutive points via the proposed sequence Edge Convolution, it can capture the underlying anatomical properties. The output filtering results highly accurate and robust across an extensive set of experiments, and fast; with a 12GB GPU, filtering a tractogram of 1M fibers requires less than a minute. Verifyber implementation and trained models are available at https://github.com/FBK-NILab/verifyber.

We present edBB-Demo, a demonstrator of an AI-powered research platform for student monitoring in remote education. The edBB platform aims to study the challenges associated to user recognition and behavior understanding in digital platforms. This platform has been developed for data collection, acquiring signals from a variety of sensors including keyboard, mouse, webcam, microphone, smartwatch, and an Electroencephalography band. The information captured from the sensors during the student sessions is modelled in a multimodal learning framework. The demonstrator includes: i) Biometric user authentication in an unsupervised environment; ii) Human action recognition based on remote video analysis; iii) Heart rate estimation from webcam video; and iv) Attention level estimation from facial expression analysis.

在许多现实世界和高影响力决策设置中，从分类过程中说明预测性不确定性的神经网络的概率预测至关重要。但是，实际上，大多数数据集经过非稳定神经网络的培训，默认情况下，这些神经网络不会捕获这种固有的不确定性。这个众所周知的问题导致了事后校准程序的开发，例如PLATT缩放（Logistic），等渗和β校准，这将得分转化为校准良好的经验概率。校准方法的合理替代方法是使用贝叶斯神经网络，该网络直接建模预测分布。尽管它们已应用于图像和文本数据集，但在表格和小型数据制度中的采用有限。在本文中，我们证明了与校准神经网络相比，贝叶斯神经网络在各种数据集中进行实验，从而产生竞争性能。

实验数据的获取成本很高，这使得很难校准复杂模型。对于许多型号而言，鉴于有限的实验预算，可以产生最佳校准的实验设计并不明显。本文介绍了用于设计实验的深钢筋学习（RL）算法，该算法通过Kalman Filter（KF）获得的Kullback-Leibler（KL）差异测量的信息增益最大化。这种组合实现了传统方法太昂贵的快速在线实验的实验设计。我们将实验的可能配置作为决策树和马尔可夫决策过程（MDP），其中每个增量步骤都有有限的操作选择。一旦采取了动作，就会使用各种测量来更新实验状态。该新数据导致KF对参数进行贝叶斯更新，该参数用于增强状态表示。与NASH-SUTCLIFFE效率（NSE）指数相反，该指数需要额外的抽样来检验前进预测的假设，KF可以通过直接估计通过其他操作获得的新数据值来降低实验的成本。在这项工作中，我们的应用集中在材料的机械测试上。使用复杂的历史依赖模型的数值实验用于验证RL设计实验的性能并基准测试实现。

我们提出了一种在多孔培养基中使用物理知识的神经网络（PINNS）中多相热力学（THM）过程中的参数鉴定的解决方案策略。我们采用无量纲的理事方程式，特别适合逆问题，我们利用了我们先前工作中开发的顺序多物理Pinn求解器。我们在多个基准问题上验证了所提出的反模型方法，包括Terzaghi的等温固结问题，Barry-Mercer的等温注射产生问题以及非饱和土壤层的非等热整合。我们报告了提出的顺序PINN-THM逆求器的出色性能，从而为将PINNS应用于复杂非线性多物理问题的逆建模铺平了道路。

论证挖掘任务需要知情的低到高复杂性语言现象和常识性知识的知情范围。先前的工作表明，预训练的语言模型在使用转移学习技术应用并建立在不同的训练前目标上时，在编码语法和语义语言现象方面非常有效。它仍然是一个问题，即现有的预训练的语言模型涵盖了参数挖掘任务的复杂性。我们依靠实验来阐明从不同词汇语义家族获得的语言模型如何利用识别论证话语单位任务的绩效。实验结果表明，转移学习技术对任务有益，并且当前的方法可能不足以利用来自不同词汇语义家族的常识性知识。