Repository der Technischen Hochschule Ingolstadt
Not a member yet
4170 research outputs found
Sort by
Charging Communication Sniffing and Man-in-the-Middle Attacks
In recent years an increasing amount of electric vehicle fast charging stations have been built to meet the growing demand from rising electric vehicle numbers. The standard for fast charging communication in europe is ISO 15118. In theory the standard includes security controls for authentication and transport encryption. In reality difficulties with implementing those security controls as well as insecure design within the standard lead to multiple possible attack vectors compromising the confidentiality and authenticity of charging communication sessions. The goal of this research is to present different approaches towards performing sniffing and man-in-the-middle attacks against charging communication. We also provide a novel approach, which does not rely on race conditions and thus is more reliable than previous approaches
Reachability of Koopman linearized systems using explicit kernel approximation and polynomial zonotope refinement
Robust Identification of Hybrid Automata from Noisy Data
In recent years, many different methods for identifying hybrid automata from data have been proposed. However, most of these methods consider clean simulator data, and consequently do not perform well for noisy data measured from real systems. We address this shortcoming with a new approach for the identification of hybrid automata that is specifically designed to be robust to noise. In particular, we propose a new high-level strategy consisting of the following three steps: clustering based on the dynamics identified from a local dataset, state space partitioning using decision trees, and conversion of the decision tree to a hybrid automaton. In addition, we introduce several new concepts for the realization of the single steps. For example, we propose an automated regularization of the dynamic models used for clustering via rank adaption, as well as a new variant of the Gini impurity index for decision tree learning, tailored toward hybrid systems where different dynamics can be active within the same state space region. As our experiments on 19 challenging benchmarks with different characteristics demonstrate, in addition to being robust to both process and measurement noise, our approach avoids the need for extensive hyper-parameter tuning and also performs well for clean data without noise
ARCH-COMP20 Category Report: Continuous and Hybrid Systems with Linear Continuous Dynamics
“Let me explain!”: exploring the potential of virtual agents in explainable AI interaction design
While the research area of artificial intelligence benefited from increasingly sophisticated machine learning techniques in recent years, the resulting systems suffer from a loss of transparency and comprehensibility, especially for end-users. In this paper, we explore the effects of incorporating virtual agents into explainable artificial intelligence (XAI) designs on the perceived trust of end-users. For this purpose, we conducted a user study based on a simple speech recognition system for keyword classification. As a result of this experiment, we found that the integration of virtual agents leads to increased user trust in the XAI system. Furthermore, we found that the user’s trust significantly depends on the modalities that are used within the user-agent interface design. The results of our study show a linear trend where the visual presence of an agent combined with a voice output resulted in greater trust than the output of text or the voice output alone. Additionally, we analysed the participants’ feedback regarding the presented XAI visualisations. We found that increased human-likeness of and interaction with the virtual agent are the two most common mention points on how to improve the proposed XAI interaction design. Based on these results, we discuss current limitations and interesting topics for further research in the field of XAI. Moreover, we present design recommendations for virtual agents in XAI systems for future projects
GANterfactual—Counterfactual Explanations for Medical Non-experts Using Generative Adversarial Learning
With the ongoing rise of machine learning, the need for methods for explaining decisions made by artificial intelligence systems is becoming a more and more important topic. Especially for image classification tasks, many state-of-the-art tools to explain such classifiers rely on visual highlighting of important areas of the input data. Contrary, counterfactual explanation systems try to enable a counterfactual reasoning by modifying the input image in a way such that the classifier would have made a different prediction. By doing so, the users of counterfactual explanation systems are equipped with a completely different kind of explanatory information. However, methods for generating realistic counterfactual explanations for image classifiers are still rare. Especially in medical contexts, where relevant information often consists of textural and structural information, high-quality counterfactual images have the potential to give meaningful insights into decision processes. In this work, we present GANterfactual, an approach to generate such counterfactual image explanations based on adversarial image-to-image translation techniques. Additionally, we conduct a user study to evaluate our approach in an exemplary medical use case. Our results show that, in the chosen medical use-case, counterfactual explanations lead to significantly better results regarding mental models, explanation satisfaction, trust, emotions, and self-efficacy than two state-of-the art systems that work with saliency maps, namely LIME and LRP