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Federated Learning for Anomaly Detection in Maritime Movement Data

Graser, Anita, Weißenfeld, Axel, Heistracher, Clemens, Dragaschnig, Melitta, Widhalm, Peter

arXiv.org Artificial Intelligence

Abstract--This paper introduces M fed, a novel solution for federated learning of movement anomaly detection models. This innovation has the potential to improve data privacy and reduce communication costs in machine learning for movement anomaly detection. We present the novel federated learning (FL) strategies employed to train M fed, perform an example experiment with maritime AIS data, and evaluate the results with respect to communication costs and FL model quality by comparing classic centralized M and the new federated M fed. The deployment of machine learning approaches in practice often faces issues of data availability and communication bandwidth bottlenecks. Particularly in the mobility domain, data is often privacy sensitive and / or the communication network may be unreliable or rate limited. One approach to address these issues is Federated Learning (FL) since it can mitigate privacy risks and reduce communication costs compared to traditional centralized machine learning [1].


Faster Certified Symmetry Breaking Using Orders With Auxiliary Variables

Anders, Markus, Bogaerts, Bart, Bogø, Benjamin, Gontier, Arthur, Koops, Wietze, McCreesh, Ciaran, Myreen, Magnus O., Nordström, Jakob, Oertel, Andy, Rebola-Pardo, Adrian, Tan, Yong Kiam

arXiv.org Artificial Intelligence

Symmetry breaking is a crucial technique in modern combinatorial solving, but it is difficult to be sure it is implemented correctly. The most successful approach to deal with bugs is to make solvers certifying, so that they output not just a solution, but also a mathematical proof of correctness in a standard format, which can then be checked by a formally verified checker. This requires justifying symmetry reasoning within the proof, but developing efficient methods for this has remained a long-standing open challenge. A fully general approach was recently proposed by Bogaerts et al. (2023), but it relies on encoding lexicographic orders with big integers, which quickly becomes infeasible for large symmetries. In this work, we develop a method for instead encoding orders with auxiliary variables. We show that this leads to orders-of-magnitude speed-ups in both theory and practice by running experiments on proof logging and checking for SAT symmetry breaking using the state-of-the-art satsuma symmetry breaker and the VeriPB proof checking toolchain.


Environment Agnostic Goal-Conditioning, A Study of Reward-Free Autonomous Learning

Åström, Hampus, Topp, Elin Anna, Malec, Jacek

arXiv.org Artificial Intelligence

In this paper we study how transforming regular reinforcement learning environments into goal-conditioned environments can let agents learn to solve tasks autonomously and reward-free. We show that an agent can learn to solve tasks by selecting its own goals in an environment-agnostic way, at training times comparable to externally guided reinforcement learning. Our method is independent of the underlying off-policy learning algorithm. Since our method is environment-agnostic, the agent does not value any goals higher than others, leading to instability in performance for individual goals. However, in our experiments, we show that the average goal success rate improves and stabilizes. An agent trained with this method can be instructed to seek any observations made in the environment, enabling generic training of agents prior to specific use cases.


A Cartography of Open Collaboration in Open Source AI: Mapping Practices, Motivations, and Governance in 14 Open Large Language Model Projects

Linåker, Johan, Osborne, Cailean, Ding, Jennifer, Burtenshaw, Ben

arXiv.org Artificial Intelligence

The proliferation of open large language models (LLMs) is fostering a vibrant ecosystem of research and innovation in artificial intelligence (AI). However, the methods of collaboration used to develop open LLMs both before and after their public release have not yet been comprehensively studied, limiting our understanding of how open LLM projects are initiated, organized, and governed as well as what opportunities there are to foster this ecosystem even further. We address this gap through an exploratory analysis of open collaboration throughout the development and reuse lifecycle of open LLMs, drawing on semi-structured interviews with the developers of 14 open LLMs from grassroots projects, research institutes, startups, and Big Tech companies in North America, Europe, Africa, and Asia. We make three key contributions to research and practice. First, collaboration in open LLM projects extends far beyond the LLMs themselves, encompassing datasets, benchmarks, open source frameworks, leaderboards, knowledge sharing and discussion forums, and compute partnerships, among others. Second, open LLM developers have a variety of social, economic, and technological motivations, from democratizing AI access and promoting open science to building regional ecosystems and expanding language representation. Third, the sampled open LLM projects exhibit five distinct organizational models, ranging from single company projects to non-profit-sponsored grassroots projects, which vary in their centralization of control and community engagement strategies used throughout the open LLM lifecycle. We conclude with practical recommendations for stakeholders seeking to support the global community building a more open future for AI.


Impact of Environmental Factors on LoRa 2.4 GHz Time of Flight Ranging Outdoors

Zhou, Yiqing, Zhou, Xule, Cheng, Zecan, Lu, Chenao, Chen, Junhan, Pan, Jiahong, Liu, Yizhuo, Li, Sihao, Kim, Kyeong Soo

arXiv.org Artificial Intelligence

In WSN/IoT, node localization is essential to long-running applications for accurate environment monitoring and event detection, often covering a large area in the field. Due to the lower time resolution of typical WSN/IoT platforms (e.g., 1 microsecond on ESP32 platforms) and the jitters in timestamping, packet-level localization techniques cannot provide meter-level resolution. For high-precision localization as well as world-wide interoperability via 2.4-GHz ISM band, a new variant of LoRa, called LoRa 2.4 GHz, was proposed by semtech, which provides a radio frequency (RF) time of flight (ToF) ranging method for meter-level localization. However, the existing datasets reported in the literature are limited in their coverages and do not take into account varying environmental factors such as temperature and humidity. To address these issues, LoRa 2.4 GHz RF ToF ranging data was collected on a sports field at the XJTLU south campus, where three LoRa nodes logged samples of ranging with a LoRa base station, together with temperature and humidity, at reference points arranged as a 3x3 grid covering 400 square meter over three weeks and uploaded all measurement records to the base station equipped with an ESP32-based transceiver for machine and user communications. The results of a preliminary investigation based on a simple deep neural network (DNN) model demonstrate that the environmental factors, including the temperature and humidity, significantly affect the accuracy of ranging, which calls for advanced methods of compensating for the effects of environmental factors on LoRa RF ToF ranging outdoors.


Normalizing Flows are Capable Visuomotor Policy Learning Models

Lind, Simon Kristoffersson, Li, Jialong, Stenmark, Maj, Krüger, Volker

arXiv.org Artificial Intelligence

Abstract-- The field of general purpose robotics has recently embraced powerful probabilistic models, such as diffusion models, to model and learn complex behaviors. However, these models often come with significant trade-offs, namely high computational costs for inference and a fundamental inability to quantify output uncertainty. We argue that a model's trustworthiness, a critical factor for reliable, general-purpose robotics, is inherently linked to its ability to provide confidence measures. In this work, we introduce Normalizing Flows Policy, a novel visuomotor policy learning model based on Normalizing Flows. We show that Normalizing Flows are a natural and powerful alternative to diffusion models, providing both a statistically sound measure of confidence and a highly efficient inference process. Through comprehensive experiments across four distinct simulated robotic tasks, we demonstrate that Normalizing Flows Policy achieves performance comparable to, and often surpassing, Diffusion Policy, and it does so not only with improved sample efficiency but also with up to 30 times faster inference. Additionally, our ablation study validates several key architectural and training techniques that enable Normalizing Flows to perform well in this domain.


Next-Generation Reservoir Computing for Dynamical Inference

Cestnik, Rok, Martens, Erik A.

arXiv.org Machine Learning

We present a simple and scalable implementation of next-generation reservoir computing for modeling dynamical systems from time series data. Our approach uses a pseudorandom nonlinear projection of time-delay embedded input, allowing an arbitrary dimension of the feature space, thus providing a flexible alternative to the polynomial-based projections used in previous next-generation reservoir computing variants. We apply the method to benchmark tasks -- including attractor reconstruction and bifurcation diagram estimation -- using only partial and noisy observations. We also include an exploratory example of estimating asymptotic oscillation phases. The models remain stable over long rollouts and generalize beyond training data. This framework enables the precise control of system state and is well suited for surrogate modeling and digital twin applications.


Query-Focused Extractive Summarization for Sentiment Explanation

Moubtahij, Ahmed, Ratté, Sylvie, Attabi, Yazid, Dumas, Maxime

arXiv.org Artificial Intelligence

Constructive analysis of feedback from clients often requires determining the cause of their sentiment from a substantial amount of text documents. To assist and improve the productivity of such endeavors, we leverage the task of Query-Focused Summarization (QFS). Models of this task are often impeded by the linguistic dissonance between the query and the source documents. We propose and substantiate a multi-bias framework to help bridge this gap at a domain-agnostic, generic level; we then formulate specialized approaches for the problem of sentiment explanation through sentiment-based biases and query expansion. We achieve experimental results outperforming baseline models on a real-world proprietary sentiment-aware QFS dataset.


PARROT: An Open Multilingual Radiology Reports Dataset

Guellec, Bastien Le, Adambounou, Kokou, Adams, Lisa C, Agripnidis, Thibault, Ahn, Sung Soo, Chalal, Radhia Ait, Antonoli, Tugba Akinci D, Amouyel, Philippe, Andersson, Henrik, Bentegeac, Raphael, Benzoni, Claudio, Blandino, Antonino Andrea, Busch, Felix, Can, Elif, Cau, Riccardo, Cavallo, Armando Ugo, Chavihot, Christelle, Chiquete, Erwin, Cuocolo, Renato, Divjak, Eugen, Ivanac, Gordana, Macek, Barbara Dziadkowiec, Elogne, Armel, Fanni, Salvatore Claudio, Ferrarotti, Carlos, Fossataro, Claudia, Fossataro, Federica, Fulek, Katarzyna, Fulek, Michal, Gac, Pawel, Gachowska, Martyna, Juarez, Ignacio Garcia, Gatti, Marco, Gorelik, Natalia, Goulianou, Alexia Maria, Hamroun, Aghiles, Herinirina, Nicolas, Kraik, Krzysztof, Krupka, Dominik, Holay, Quentin, Kitamura, Felipe, Klontzas, Michail E, Kompanowska, Anna, Kompanowski, Rafal, Lefevre, Alexandre, Lemke, Tristan, Lindholz, Maximilian, Muller, Lukas, Macek, Piotr, Makowski, Marcus, Mannacio, Luigi, Meddeb, Aymen, Natale, Antonio, Edzang, Beatrice Nguema, Ojeda, Adriana, Park, Yae Won, Piccione, Federica, Ponsiglione, Andrea, Poreba, Malgorzata, Poreba, Rafal, Prucker, Philipp, Pruvo, Jean Pierre, Pugliesi, Rosa Alba, Rabemanorintsoa, Feno Hasina, Rafailidis, Vasileios, Resler, Katarzyna, Rotkegel, Jan, Saba, Luca, Siebert, Ezann, Stanzione, Arnaldo, Tekin, Ali Fuat, Yanchapaxi, Liz Toapanta, Triantafyllou, Matthaios, Tsaoulia, Ekaterini, Vassalou, Evangelia, Vernuccio, Federica, Wasselius, Johan, Wang, Weilang, Urban, Szymon, Wlodarczak, Adrian, Wlodarczak, Szymon, Wysocki, Andrzej, Xu, Lina, Zatonski, Tomasz, Zhang, Shuhang, Ziegelmayer, Sebastian, Kuchcinski, Gregory, Bressem, Keno K

arXiv.org Artificial Intelligence

Rationale and Objectives: To develop and validate PARROT (Polyglottal Annotated Radiology Reports for Open Testing), a large, multicentric, open-access dataset of fictional radiology reports spanning multiple languages for testing natural language processing applications in radiology. Materials and Methods: From May to September 2024, radiologists were invited to contribute fictional radiology reports following their standard reporting practices. Contributors provided at least 20 reports with associated metadata including anatomical region, imaging modality, clinical context, and for non-English reports, English translations. All reports were assigned ICD-10 codes. A human vs. AI report differentiation study was conducted with 154 participants (radiologists, healthcare professionals, and non-healthcare professionals) assessing whether reports were human-authored or AI-generated. Results: The dataset comprises 2,658 radiology reports from 76 authors across 21 countries and 13 languages. Reports cover multiple imaging modalities (CT: 36.1%, MRI: 22.8%, radiography: 19.0%, ultrasound: 16.8%) and anatomical regions, with chest (19.9%), abdomen (18.6%), head (17.3%), and pelvis (14.1%) being most prevalent. In the differentiation study, participants achieved 53.9% accuracy (95% CI: 50.7%-57.1%) in distinguishing between human and AI-generated reports, with radiologists performing significantly better (56.9%, 95% CI: 53.3%-60.6%, p<0.05) than other groups. Conclusion: PARROT represents the largest open multilingual radiology report dataset, enabling development and validation of natural language processing applications across linguistic, geographic, and clinical boundaries without privacy constraints.


Impact of Gaze-Based Interaction and Augmentation on Human-Robot Collaboration in Critical Tasks

Jena, Ayesha, Reitmann, Stefan, Topp, Elin Anna

arXiv.org Artificial Intelligence

-- We present a user study analyzing head-gaze-based robot control and foveated visual augmentation in a simulated search-and-rescue task. Results show that foveated augmentation significantly improves task performance, reduces cognitive load by 38%, and shortens task time by over 60%. Head-gaze patterns analysed over both the entire task duration and shorter time segments show that near and far attention capture is essential to better understand user intention in critical scenarios. Our findings highlight the potential of foveation as an augmentation technique and the need to further study gaze measures to leverage them during critical tasks. I. INTRODUCTION Advancements in the field of robotics have led to a need for seamless collaboration and effective communication between humans and robots in different scenarios [1].