Performance Analysis
EEG-Driven AR-Robot System for Zero-Touch Grasping Manipulation
Wang, Junzhe, Xie, Jiarui, Hao, Pengfei, Li, Zheng, Cai, Yi
Reliable brain-computer interface (BCI) control of robots provides an intuitive and accessible means of human-robot interaction, particularly valuable for individuals with motor impairments. However, existing BCI-Robot systems face major limitations: electroencephalography (EEG) signals are noisy and unstable, target selection is often predefined and inflexible, and most studies remain restricted to simulation without closed-loop validation. These issues hinder real-world deployment in assistive scenarios. To address them, we propose a closed-loop BCI-AR-Robot system that integrates motor imagery (MI)-based EEG decoding, augmented reality (AR) neurofeedback, and robotic grasping for zero-touch operation. A 14-channel EEG headset enabled individualized MI calibration, a smartphone-based AR interface supported multi-target navigation with direction-congruent feedback to enhance stability, and the robotic arm combined decision outputs with vision-based pose estimation for autonomous grasping. Experiments are conducted to validate the framework: MI training achieved 93.1 percent accuracy with an average information transfer rate (ITR) of 14.8 bit/min; AR neurofeedback significantly improved sustained control (SCI = 0.210) and achieved the highest ITR (21.3 bit/min) compared with static, sham, and no-AR baselines; and closed-loop grasping achieved a 97.2 percent success rate with good efficiency and strong user-reported control. These results show that AR feedback substantially stabilizes EEG-based control and that the proposed framework enables robust zero-touch grasping, advancing assistive robotic applications and future modes of human-robot interaction.
Scaling Up ROC-Optimizing Support Vector Machines
Binary classification is a fundamental problem in machine learning. Given a pair (X, Y), where X is a p-dimensional predictor and Y is a binary response taking values in { 1, 1}, the goal is to learn a decision function f of X that predicts Y by ห Y = sign{f(X)}. A canonical approach is to choose f that minimizes the classification error, or equivalently, maximizes the accuracy. For instance, the support vector machine (SVM; Vapnik, 1999) determines the decision function by maximizing the geometric margin, which effectively aligns with maximizing accuracy [Lin, 2002]. However, in imbalanced settings where one class is substantially underrepresented, accuracy can be a misleading measure of performance. Even a trivial classifier that always predicts the majority class can achieve high accuracy while completely failing to detect samples from the minor class. As an alternative, the receiver operating characteristic (ROC) curve is widely used to evaluate classifier performance under class imbalance. By definition, the ROC curve plots the true positive rate (TPR) against the false positive rate (FPR) to summarize classification performance, and the area under the ROC curve (AUC) serves as a popular scalar summary. A classifier with a larger AUC value is generally regarded as having better classification performance.
Pediatric Appendicitis Detection from Ultrasound Images
Hosseinabadi, Fatemeh, Sharifi, Seyedhassan
Pediatric appendicitis remains one of the most common causes of acute abdominal pain in children, and its diagnosis continues to challenge clinicians due to overlapping symptoms and variable imaging quality. This study aims to develop and evaluate a deep learning model based on a pretrained ResNet architecture for automated detection of appendicitis from ultrasound images. We used the Regensburg Pediatric Appendicitis Dataset, which includes ultrasound scans, laboratory data, and clinical scores from pediatric patients admitted with abdominal pain to Children Hospital. Hedwig in Regensburg, Germany. Each subject had 1 to 15 ultrasound views covering the right lower quadrant, appendix, lymph nodes, and related structures. For the image based classification task, ResNet was fine tuned to distinguish appendicitis from non-appendicitis cases. Images were preprocessed by normalization, resizing, and augmentation to enhance generalization. The proposed ResNet model achieved an overall accuracy of 93.44, precision of 91.53, and recall of 89.8, demonstrating strong performance in identifying appendicitis across heterogeneous ultrasound views. The model effectively learned discriminative spatial features, overcoming challenges posed by low contrast, speckle noise, and anatomical variability in pediatric imaging.
PLLuM: A Family of Polish Large Language Models
Kocoล, Jan, Piasecki, Maciej, Janz, Arkadiusz, Ferdinan, Teddy, Radliลski, ลukasz, Koptyra, Bartลomiej, Oleksy, Marcin, Woลบniak, Stanisลaw, Walkowiak, Paweล, Wojtasik, Konrad, Moska, Julia, Naskrฤt, Tomasz, Walkowiak, Bartosz, Gniewkowski, Mateusz, Szyc, Kamil, Motyka, Dawid, Banach, Dawid, Dalasiลski, Jonatan, Rudnicka, Ewa, Alberski, Bartลomiej, Walkowiak, Tomasz, Szczฤsny, Aleksander, Markiewicz, Maciej, Bernaล, Tomasz, Mazur, Hubert, ลปyta, Kamil, Tykierko, Mateusz, Chodak, Grzegorz, Kajdanowicz, Tomasz, Kazienko, Przemysลaw, Karliลska, Agnieszka, Seweryn, Karolina, Koลos, Anna, Chrabฤ szcz, Maciej, Lorenc, Katarzyna, Krasnodฤbska, Aleksandra, Wilczek, Artur, Dziewulska, Katarzyna, Betscher, Paula, Cieลliลska, Zofia, Kowol, Katarzyna, Mikoล, Daria, Trzciลski, Maciej, Krutul, Dawid, Kozลowski, Marek, Dadas, Sลawomir, Poลwiata, Rafaล, Pereลkiewicz, Michaล, Grฤbowiec, Maลgorzata, Kazuลa, Maciej, Biaลas, Marcin, Roszko, Roman, Roszko, Danuta, Vaiฤenonienฤ, Jurgita, Utka, Andrius, Levchuk, Paweล, Kowalski, Paweล, Prawdzic-Jankowska, Irena, Ogrodniczuk, Maciej, Borys, Monika, Buliลska, Anna, Gumienna, Wiktoria, Kieraล, Witold, Komosiลska, Dorota, Krasnowska-Kieraล, Katarzyna, Kobyliลski, ลukasz, Lewandowska, Martyna, ลaziลski, Marek, ลฤ tkowski, Mikoลaj, Mastalerz, Dawid, Milewicz, Beata, Mykowiecka, Agnieszka Anna, Peljak-ลapiลska, Angelika, Penno, Sandra, Przybysz, Zuzanna, Rudolf, Michaล, Rybak, Piotr, Saputa, Karolina, Tomaszewska, Aleksandra, Wawer, Aleksander, Woliลski, Marcin, Woลoszyn, Joanna, Wrรณblewska, Alina, ลปuk, Bartosz, ลปarnecki, Filip, Kaczyลski, Konrad, Cichosz, Anna, Deckert, Zuzanna, Garnys, Monika, Grabarczyk, Izabela, Janowski, Wojciech, Karasiลska, Sylwia, Kujawiak, Aleksandra, Misztela, Piotr, Szymaลska, Maria, Walkusz, Karolina, Siek, Igor, Kwiatkowski, Jakub, Pฤzik, Piotr
Large Language Models (LLMs) play a central role in modern artificial intelligence, yet their development has been primarily focused on English, resulting in limited support for other languages. We present PLLuM (Polish Large Language Model), the largest open-source family of foundation models tailored specifically for the Polish language. Developed by a consortium of major Polish research institutions, PLLuM addresses the need for high-quality, transparent, and culturally relevant language models beyond the English-centric commercial landscape. We describe the development process, including the construction of a new 140-billion-token Polish text corpus for pre-training, a 77k custom instructions dataset, and a 100k preference optimization dataset. A key component is a Responsible AI framework that incorporates strict data governance and a hybrid module for output correction and safety filtering. We detail the models' architecture, training procedures, and alignment techniques for both base and instruction-tuned variants, and demonstrate their utility in a downstream task within public administration. By releasing these models publicly, PLLuM aims to foster open research and strengthen sovereign AI technologies in Poland.
Fair and Explainable Credit-Scoring under Concept Drift: Adaptive Explanation Frameworks for Evolving Populations
Evolving borrower behaviors, shifting economic conditions, and changing regulatory landscapes continuously reshape the data distributions underlying modern credit-scoring systems. Conventional explainability techniques, such as SHAP, assume static data and fixed background distributions, making their explanations unstable and potentially unfair when concept drift occurs. This study addresses that challenge by developing adaptive explanation frameworks that recalibrate interpretability and fairness in dynamically evolving credit models. Using a multi-year credit dataset, we integrate predictive modeling via XGBoost with three adaptive SHAP variants: (A) per-slice explanation reweighting that adjusts for feature distribution shifts, (B) drift-aware SHAP rebaselining with sliding-window background samples, and (C) online surrogate calibration using incremental Ridge regression. Each method is benchmarked against static SHAP explanations using metrics of predictive performance (AUC, F1), directional and rank stability (cosine, Kendall tau), and fairness (demographic parity and recalibration). Results show that adaptive methods, particularly rebaselined and surrogate-based explanations, substantially improve temporal stability and reduce disparate impact across demographic groups without degrading predictive accuracy. Robustness tests, including counterfactual perturbations, background sensitivity analysis, and proxy-variable detection, confirm the resilience of adaptive explanations under real-world drift conditions. These findings establish adaptive explainability as a practical mechanism for sustaining transparency, accountability, and ethical reliability in data-driven credit systems, and more broadly, in any domain where decision models evolve with population change.
What's in Common? Multimodal Models Hallucinate When Reasoning Across Scenes
Ross, Candace, Bordes, Florian, Williams, Adina, Kirichenko, Polina, Ibrahim, Mark
Multimodal language models possess a remarkable ability to handle an open-vocabulary's worth of objects. Yet the best models still suffer from hallucinations when reasoning about scenes in the real world, revealing a gap between their seemingly strong performance on existing perception benchmarks that are saturating and their reasoning in the real world. To address this gap, we build a novel benchmark of in-the-wild scenes that we call Common-O. With more than 10.5k examples using exclusively new images not found in web training data to avoid contamination, Common-O goes beyond just perception, inspired by cognitive tests for humans, to probe reasoning across scenes by asking "what's in common?". We evaluate leading multimodal language models, including models specifically trained to perform chain-of-thought reasoning. We find that perceiving objects in single images is tractable for most models, yet reasoning across scenes is very challenging even for the best models, including reasoning models. Despite saturating many leaderboards focusing on perception, the best performing model only achieves 35% on Common-O -- and on Common-O Complex, consisting of more complex scenes, the best model achieves only 1%. Curiously, we find models are more prone to hallucinate when similar objects are present in the scene, suggesting models may be relying on object co-occurrence seen during training. Among the models we evaluated, we found scale can provide modest improvements while models explicitly trained with multi-image inputs show bigger improvements, suggesting scaled multi-image training may offer promise. We make our benchmark publicly available to spur research into the challenge of hallucination when reasoning across scenes.
Machine Learning for Electron-Scale Turbulence Modeling in W7-X
Farcas, Ionut-Gabriel, Fernando, Don Lawrence Carl Agapito, Navarro, Alejandro Banon, Merlo, Gabriele, Jenko, Frank
Constructing reduced models for turbulent transport is essential for accelerating profile predictions and enabling many-query tasks such as uncertainty quantification, parameter scans, and design optimization. This paper presents machine-learning-driven reduced models for Electron Temperature Gradient (ETG) turbulence in the Wendelstein 7-X (W7-X) stellarator. Each model predicts the ETG heat flux as a function of three plasma parameters: the normalized electron temperature radial gradient ($ฯ_{T_e}$), the ratio of normalized electron temperature and density radial gradients ($ฮท_e$), and the electron-to-ion temperature ratio ($ฯ$). We first construct models across seven radial locations using regression and an active machine-learning-based procedure. This process initializes models using low-cardinality sparse-grid training data and then iteratively refines their training sets by selecting the most informative points from a pre-existing simulation database. We evaluate the prediction capabilities of our models using out-of-sample datasets with over $393$ points per location, and $95\%$ prediction intervals are estimated via bootstrapping to assess prediction uncertainty. We then investigate the construction of generalized reduced models, including a generic, position-independent model, and assess their heat flux prediction capabilities at three additional locations. Our models demonstrate robust performance and predictive accuracy comparable to the original reference simulations, even when applied beyond the training domain.
Guided by Stars: Interpretable Concept Learning Over Time Series via Temporal Logic Semantics
Ferfoglia, Irene, Silvetti, Simone, Saveri, Gaia, Nenzi, Laura, Bortolussi, Luca
Time series classification is a task of paramount importance, as this kind of data often arises in safety-critical applications. However, it is typically tackled with black-box deep learning methods, making it hard for humans to understand the rationale behind their output. To take on this challenge, we propose a novel approach, STELLE (Signal Temporal logic Embedding for Logically-grounded Learning and Explanation), a neuro-symbolic framework that unifies classification and explanation through direct embedding of trajectories into a space of temporal logic concepts. By introducing a novel STL-inspired kernel that maps raw time series to their alignment with predefined STL formulae, our model jointly optimises accuracy and interpretability, as each prediction is accompanied by the most relevant logical concepts that characterise it. This yields (i) local explanations as human-readable STL conditions justifying individual predictions, and (ii) global explanations as class-characterising formulae. Experiments demonstrate that STELLE achieves competitive accuracy while providing logically faithful explanations, validated on diverse real-world benchmarks.
CantoASR: Prosody-Aware ASR-LALM Collaboration for Low-Resource Cantonese
Chen, Dazhong, Lin, Yi-Cheng, Huang, Yuchen, Gong, Ziwei, Jiang, Di, Xie, Zeying, R., Yi, Fung, null
Automatic speech recognition (ASR) is critical for language accessibility, yet low-resource Cantonese remains challenging due to limited annotated data, six lexical tones, tone sandhi, and accent variation. Existing ASR models, such as Whisper, often suffer from high word error rates. Large audio-language models (LALMs), in contrast, can leverage broader contextual reasoning but still require explicit tonal and prosodic acoustic cues. We introduce CantoASR, a collaborative ASR-LALM error correction framework that integrates forced alignment for acoustic feature extraction, a LoRA-finetuned Whisper for improved tone discrimination, and an instruction-tuned Qwen-Audio for prosody-aware correction. Evaluations on spontaneous Cantonese data show substantial CER gains over Whisper-Large-V3. These findings suggest that integrating acoustic cues with LALM reasoning provides a scalable strategy for low-resource tonal and dialectal ASR.
Automated and Explainable Denial of Service Analysis for AI-Driven Intrusion Detection Systems
Yakubu, Paul Badu, Santana, Lesther, Rahouti, Mohamed, Xin, Yufeng, Chehri, Abdellah, Aledhari, Mohammed
With the increasing frequency and sophistication of Distributed Denial of Service (DDoS) attacks, it has become critical to develop more efficient and interpretable detection methods. Traditional detection systems often struggle with scalability and transparency, hindering real-time response and understanding of attack vectors. This paper presents an automated framework for detecting and interpreting DDoS attacks using machine learning (ML). The proposed method leverages the Tree-based Pipeline Optimization Tool (TPOT) to automate the selection and optimization of ML models and features, reducing the need for manual experimentation. SHapley Additive exPlanations (SHAP) is incorporated to enhance model interpretability, providing detailed insights into the contribution of individual features to the detection process. By combining TPOT's automated pipeline selection with SHAP interpretability, this approach improves the accuracy and transparency of DDoS detection. Experimental results demonstrate that key features such as mean backward packet length and minimum forward packet header length are critical in detecting DDoS attacks, offering a scalable and explainable cybersecurity solution.