While preference modelling is becoming one of the pillars of machine learning, the problem of preference explanation remains challenging and underexplored. In this paper, we propose \textsc{Pref-SHAP}, a Shapley value-based model explanation framework for pairwise comparison data. We derive the appropriate value functions for preference models and further extend the framework to model and explain \emph{context specific} information, such as the surface type in a tennis game. To demonstrate the utility of \textsc{Pref-SHAP}, we apply our method to a variety of synthetic and real-world datasets and show that richer and more insightful explanations can be obtained over the baseline.

In the last years, the number of IoT devices deployed has suffered an undoubted explosion, reaching the scale of billions. However, some new cybersecurity issues have appeared together with this development. Some of these issues are the deployment of unauthorized devices, malicious code modification, malware deployment, or vulnerability exploitation. This fact has motivated the requirement for new device identification mechanisms based on behavior monitoring. Besides, these solutions have recently leveraged Machine and Deep Learning techniques due to the advances in this field and the increase in processing capabilities. In contrast, attackers do not stay stalled and have developed adversarial attacks focused on context modification and ML/DL evaluation evasion applied to IoT device identification solutions. This work explores the performance of hardware behavior-based individual device identification, how it is affected by possible context- and ML/DL-focused attacks, and how its resilience can be improved using defense techniques. In this sense, it proposes an LSTM-CNN architecture based on hardware performance behavior for individual device identification. Then, previous techniques have been compared with the proposed architecture using a hardware performance dataset collected from 45 Raspberry Pi devices running identical software. The LSTM-CNN improves previous solutions achieving a +0.96 average F1-Score and 0.8 minimum TPR for all devices. Afterward, context- and ML/DL-focused adversarial attacks were applied against the previous model to test its robustness. A temperature-based context attack was not able to disrupt the identification. However, some ML/DL state-of-the-art evasion attacks were successful. Finally, adversarial training and model distillation defense techniques are selected to improve the model resilience to evasion attacks, without degrading its performance.

Cybercriminals are moving towards zero-day attacks affecting resource-constrained devices such as single-board computers (SBC). Assuming that perfect security is unrealistic, Moving Target Defense (MTD) is a promising approach to mitigate attacks by dynamically altering target attack surfaces. Still, selecting suitable MTD techniques for zero-day attacks is an open challenge. Reinforcement Learning (RL) could be an effective approach to optimize the MTD selection through trial and error, but the literature fails when i) evaluating the performance of RL and MTD solutions in real-world scenarios, ii) studying whether behavioral fingerprinting is suitable for representing SBC's states, and iii) calculating the consumption of resources in SBC. To improve these limitations, the work at hand proposes an online RL-based framework to learn the correct MTD mechanisms mitigating heterogeneous zero-day attacks in SBC. The framework considers behavioral fingerprinting to represent SBCs' states and RL to learn MTD techniques that mitigate each malicious state. It has been deployed on a real IoT crowdsensing scenario with a Raspberry Pi acting as a spectrum sensor. More in detail, the Raspberry Pi has been infected with different samples of command and control malware, rootkits, and ransomware to later select between four existing MTD techniques. A set of experiments demonstrated the suitability of the framework to learn proper MTD techniques mitigating all attacks (except a harmfulness rootkit) while consuming <1 MB of storage and utilizing <55% CPU and <80% RAM.

Content moderation is the process of screening and monitoring user-generated content online. It plays a crucial role in stopping content resulting from unacceptable behaviors such as hate speech, harassment, violence against specific groups, terrorism, racism, xenophobia, homophobia, or misogyny, to mention some few, in Online Social Platforms. These platforms make use of a plethora of tools to detect and manage malicious information; however, malicious actors also improve their skills, developing strategies to surpass these barriers and continuing to spread misleading information. Twisting and camouflaging keywords are among the most used techniques to evade platform content moderation systems. In response to this recent ongoing issue, this paper presents an innovative approach to address this linguistic trend in social networks through the simulation of different content evasion techniques and a multilingual Transformer model for content evasion detection. In this way, we share with the rest of the scientific community a multilingual public tool, named "pyleetspeak" to generate/simulate in a customizable way the phenomenon of content evasion through automatic word camouflage and a multilingual Named-Entity Recognition (NER) Transformer-based model tuned for its recognition and detection. The multilingual NER model is evaluated in different textual scenarios, detecting different types and mixtures of camouflage techniques, achieving an overall weighted F1 score of 0.8795. This article contributes significantly to countering malicious information by developing multilingual tools to simulate and detect new methods of evasion of content on social networks, making the fight against information disorders more effective.

The deployment of robots in uncontrolled environments requires them to operate robustly under previously unseen scenarios, like irregular terrain and wind conditions. Unfortunately, while rigorous safety frameworks from robust optimal control theory scale poorly to high-dimensional nonlinear dynamics, control policies computed by more tractable "deep" methods lack guarantees and tend to exhibit little robustness to uncertain operating conditions. This work introduces a novel approach enabling scalable synthesis of robust safety-preserving controllers for robotic systems with general nonlinear dynamics subject to bounded modeling error by combining game-theoretic safety analysis with adversarial reinforcement learning in simulation. Following a soft actor-critic scheme, a safety-seeking fallback policy is co-trained with an adversarial "disturbance" agent that aims to invoke the worst-case realization of model error and training-to-deployment discrepancy allowed by the designer's uncertainty. While the learned control policy does not intrinsically guarantee safety, it is used to construct a real-time safety filter (or shield) with robust safety guarantees based on forward reachability rollouts. This shield can be used in conjunction with a safety-agnostic control policy, precluding any task-driven actions that could result in loss of safety. We evaluate our learning-based safety approach in a 5D race car simulator, compare the learned safety policy to the numerically obtained optimal solution, and empirically validate the robust safety guarantee of our proposed safety shield against worst-case model discrepancy.

With 84.75 million Filipinos online, the ability for models to process online text is crucial for developing Filipino NLP applications. To this end, spelling correction is a crucial preprocessing step for downstream processing. However, the lack of data prevents the use of language models for this task. In this paper, we propose an N-Gram + Damerau Levenshtein distance model with automatic rule extraction. We train the model on 300 samples, and show that despite limited training data, it achieves good performance and outperforms other deep learning approaches in terms of accuracy and edit distance. Moreover, the model (1) requires little compute power, (2) trains in little time, thus allowing for retraining, and (3) is easily interpretable, allowing for direct troubleshooting, highlighting the success of traditional approaches over more complex deep learning models in settings where data is unavailable.

基于视觉的导航需要处理复杂的信息以做出以任务为导向的决策。应用包括自动驾驶机器人，自动驾驶汽车以及对人类的辅助愿景。该过程中的关键要素之一是在像素空间中提取和选择相关特征，以便基于操作选择，适合哪种机器学习技术。但是，在模拟中接受培训的深度强化学习代理人在现实世界中部署在现实世界中通常会表现出不满意的结果，这是因为感知差异称为$ \ textit {现实gap} $。尚未探索以弥合这一差距的方法是自我注意力。在本文中，我们（1）对基于3D环境的基于自我注意力的导航进行系统探索，并从不同的超参数集中观察到的行为，包括它们的概括能力； （2）目前的策略来提高代理的概括能力和导航行为； （3）展示在模拟中训练的模型如何能够实时处理现实世界图像。据我们所知，这是使用少于4000个参数成功导航3D动作空间的基于自我注意力的代理的首次演示。

嗜睡是驾驶员和交通事故主要原因之一的主要关注点。认知神经科学和计算机科学的进步已通过使用脑部计算机界面（BCIS）和机器学习（ML）来检测驾驶员的嗜睡。然而，几个挑战仍然开放，应该面对。首先，文献中缺少使用一组ML算法的多种ML算法对嗜睡检测性能的全面评估。最后，需要研究适合受试者组的可扩展ML模型的检测性能，并将其与文献中提出的单个模型进行比较。为了改善这些局限性，这项工作提出了一个智能框架，该框架采用了BCIS和基于脑电图（EEG）的功能，以检测驾驶场景中的嗜睡。 SEED-VIG数据集用于喂食不同的ML回归器和三类分类器，然后评估，分析和比较单个受试者和组的表现最佳模型。有关单个模型的更多详细信息，随机森林（RF）获得了78％的F1分数，改善了通过文献中使用的模型（例如支持向量机（SVM））获得的58％。关于可扩展模型，RF达到了79％的F1得分，证明了这些方法的有效性。所学的经验教训可以总结如下：i）不仅SVM，而且文献中未充分探索的其他模型与嗜睡检测有关，ii）ii）适用于受试者组的可伸缩方法也有效地检测嗜睡，即使新受试者也是如此评估模型培训中未包括的。

从单个图像中恢复人头的几何形状，同时对材料和照明进行分解是一个严重不良的问题，需要事先解决。基于3D形态模型（3DMM）及其与可区分渲染器的组合的方法已显示出令人鼓舞的结果。但是，3DMM的表现力受到限制，它们通常会产生过度平滑和身份敏捷的3D形状，仅限于面部区域。最近，使用多层感知器参数化几何形状的神经场获得了高度准确的全头部重建。这些表示形式的多功能性也已被证明可有效解开几何形状，材料和照明。但是，这些方法需要几十个输入图像。在本文中，我们介绍了Sira，该方法从单个图像中，从一个图像中重建了具有高保真度几何形状和分解的灯光和表面材料的人头头像。我们的关键成分是基于神经场的两个数据驱动的统计模型，这些模型可以解决单视3D表面重建和外观分解的歧义。实验表明，Sira获得了最新的状态导致3D头重建，同时它成功地解开了全局照明以及弥漫性和镜面反照率。此外，我们的重建适合基于物理的外观编辑和头部模型重新构建。

尽管变压器语言模型（LMS）是信息提取的最新技术，但长文本引入了需要次优的预处理步骤或替代模型体系结构的计算挑战。稀疏注意的LMS可以代表更长的序列，克服性能障碍。但是，目前尚不清楚如何解释这些模型的预测，因为并非所有令牌都在自我发项层中相互参加，而在运行时，长序列对可解释性算法提出了计算挑战，而当运行时取决于文档长度。这些挑战在文档可能很长的医学环境中是严重的，机器学习（ML）模型必须是审核和值得信赖的。我们介绍了一种新颖的蒙版抽样程序（MSP），以识别有助于预测的文本块，将MSP应用于预测医学文本诊断的背景下，并通过两位临床医生的盲目审查来验证我们的方法。我们的方法比以前的最先进的临床信息块高约1.7倍，速度更快100倍，并且可用于生成重要的短语对。 MSP特别适合长LMS，但可以应用于任何文本分类器。我们提供了MSP的一般实施。