Publications

Multi-purpose tactile perception based on deep learning in a new tendon-driven optical tactile sensor

By Zhou Zhao, Zhenyu Lu

2022-10-01

In 2022 IEEE/RSJ international conference on intelligent robots and systems

Abstract

In this paper, we create a new tendon-connected multi-functional optical tactile sensor, MechTac, for object perception in field of view (TacTip) and location of touching points in the blind area of vision (TacSide). In a multi-point touch task, the information of the TacSide and the TacTip are overlapped to commonly affect the distribution of papillae pins on the TacTip. Since the effects of TacSide are much less obvious to those affected on the TacTip, a perceiving out-of-view neural network (O$^2$VNet) is created to separate the mixed information with unequal affection. To reduce the dependence of the O$^2$VNet on the grayscale information of the image, we create one new binarized convolutional (BConv) layer in front of the backbone of the O$^2$VNet. The O$^2$VNet can not only achieve real-time temporal sequence prediction (34 ms per image), but also attain the average classification accuracy of 99.06%. The experimental results show that the O$^2$VNet can hold high classification accuracy even facing the image contrast changes.

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Discovering and visualizing tactics in table tennis games based on subgroup discovery

By Pierre Duluard, Xinqing Li, Marc Plantevit, Céline Robardet, Romain Vuillemot

2022-09-19

In Machine learning and data mining for sports analytics - 9th international workshop, MLSA 2022

Abstract

We report on preliminary results to automatically identify efficient tactics of elite players in table tennis games. We define such tactics as subgroups of winning strokes which table tennis experts sought to obtain to train players and adapt their strategy during games. We first report on the creation of such subgroups and their ranking by weighted relative accuracy measure (WRAcc). We then report on representation of the subgroups using visualizations that enabled our expert to provide rapid feedback and hence provided us with guidance towards further improvements of our discoveries

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Improving the quality of rule-based GNN explanations

By Ataollah Kamal, Elouan Vincent, Marc Plantevit, Céline Robardet

2022-09-12

In Workshop on eXplainable knowledge discovery in data mining. Machine learning and principles and practice of knowledge discovery in databases - international workshops of ECML PKDD 2022, grenoble, france, september 19-23, 2022, proceedings, part I

Abstract

Recent works have proposed to explain GNNs using activation rules. Activation rules allow to capture specific configurations in the embedding space of a given layer that is discriminant for the GNN decision. These rules also catch hidden features of input graphs. This requires to associate these rules to representative graphs. In this paper, we propose on the one hand an analysis of heuristic-based algorithms to extract the activation rules, and on the other hand the use of transport-based optimal graph distances to associate each rule with the most specific graph that triggers them.

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A Kleene theorem for higher-dimensional automata

By Uli Fahrenberg, Christian Johansen, Georg Struth, Krzysztof Ziemiański

2022-09-06

In 33rd international conference on concurrency theory (CONCUR 2022)

Abstract

We prove a Kleene theorem for higher-dimensional automata (HDAs). It states that the languages they recognise are precisely the rational subsumption-closed sets of interval pomsets. The rational operations include a gluing composition, for which we equip pomsets with interfaces. For our proof, we introduce HDAs with interfaces as presheaves over labelled precube categories and use tools inspired by algebraic topology, such as cylinders and (co)fibrations. HDAs are a general model of non-interleaving concurrency, which subsumes many other models in this field. Interval orders are used as models for concurrent or distributed systems where events extend in time. Our tools and techniques may therefore yield templates for Kleene theorems in various models and applications.

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A machine learning based approach for the detection of sybil attacks in c-ITS

By Badis Hammi, Mohamed Yacine Idir, Rida Khatoun

2022-09-01

In The 23rd asia-pacific network operations and management symposium

Abstract

The intrusion detection systems are vital for the sustainability of Cooperative Intelligent Transportation Systems (C-ITS) and the detection of sybil attacks are particularly challenging. In this work, we propose a novel approach for the detection of sybil attacks in C-ITS environments. We provide an evaluation of our approach using extensive simulations that rely on real traces, showing our detection approach?s effectiveness.

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Comparing use-cases of tree-fold vs fold-left, how to fold and color a map

Abstract

In this article we examine some consequences of computation order of two different conceptual implementations of the fold function. We explore a set of performance- and accuracy-based experiments on two implementations of this function. In particular, we contrast the traditional fold-left implementation with another approach we refer to as tree-fold. It is often implicitly supposed that the binary operation in question has constant complexity. We explore several application areas which diverge from that assumption: rational arithmetic, floating-point arithmetic, and Binary Decisions Diagram construction. These are binary operations which degrade in performance as the fold iteration progresses. We show that these types of binary operations are good candidates for tree-fold.

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Label-efficient self-supervised speaker verification with information maximization and contrastive learning

By Théo Lepage, Réda Dehak

2022-08-28

In Proceedings of the 23rd annual conference of the international speech communication association (interspeech 2022)

Abstract

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Using subgroup discovery to relate odor pleasantness and intensity to peripheral nervous system reactions

By Maelle Moranges, Marc Plantevit, Moustafa Bensafi

2022-07-24

In IEEE Transactions on Affective Computing

Abstract

Activation of the autonomic nervous system is a primary characteristic of human hedonic responses to sensory stimuli. For smells, general tendencies of physiological reactions have been described using classical statistics. However, these physiological variations are generally not quantified precisely; each psychophysiological parameter has very often been studied separately and individual variability was not systematically considered. The current study presents an innovative approach based on data mining, whose goal is to extract knowledge from a dataset. This approach uses a subgroup discovery algorithm which allows extraction of rules that apply to as many olfactory stimuli and individuals as possible. These rules are described by intervals on a set of physiological attributes. Results allowed both quantifying how each physiological parameter relates to odor pleasantness and perceived intensity but also describing the participation of each individual to these rules. This approach can be applied to other fields of affective sciences characterized by complex and heterogeneous datasets.

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What does my GNN really capture? On exploring internal GNN representations

By Luca Veyrin-Forrer, Ataollah Kamal, Stefan Duffner, Marc Plantevit, Céline Robardet

2022-07-23

In Proceedings of the 31st international joint conference on artificial intelligence (IJCAI’22)

Abstract

GNNs are efficient for classifying graphs but their internal workings is opaque which limits their field of application. Existing methods for explaining GNN focus on disclosing the relationships between input graphs and the model’s decision. In contrary, the method we propose isolates internal features, hidden in the network layers, which are automatically identified by the GNN to classify graphs. We show that this method makes it possible to know the parts of the input graphs used by GNN with much less bias than the SOTA methods and therefore to provide confidence in the decision process.

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