mahalanobis
- North America > United States > Michigan (0.04)
- North America > Canada (0.04)
- Europe > Italy > Calabria > Catanzaro Province > Catanzaro (0.04)
- Government > Military (0.50)
- Information Technology > Security & Privacy (0.40)
- North America > United States > Massachusetts > Middlesex County > Cambridge (0.05)
- North America > Canada > Quebec > Montreal (0.04)
- Asia > Middle East > Israel (0.04)
Latent-space metrics for Complex-Valued VAE out-of-distribution detection under radar clutter
Rouzoumka, Y. A., Terreaux, E., Morisseau, C., Ovarlez, J. -P., Ren, C.
We therefore pursue a data-driven alternative based on complex-valued V AEs and latent-space OOD scores. In recent years, data-driven approaches have emerged to alleviate the need for precise clutter modeling. Among them, V AEs [4] have demonstrated promising capabilities for anomaly and OOD detection in diverse applications, including radar detection [5], speech enhancement [6], medical imaging [7], industrial monitoring [8], and acoustic signal analysis [9]. These models learn a latent representation of the training data and use reconstruction or probabilistic criteria to detect deviations. Despite their effectiveness, most V AE-based detectors operate in the real domain and often treat complex-valued radar data by separating real and imaginary components into distinct channels. Recent advances in Complex-V alued Neural Networks (CVNNs) have shown the benefits of directly modeling complex-valued signals [10, 11].
- Europe > France (0.05)
- North America > United States (0.04)
- Asia > South Korea > Seoul > Seoul (0.04)
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A Simple Unified Framework for Detecting Out-of-Distribution Samples and Adversarial Attacks
Kimin Lee, Kibok Lee, Honglak Lee, Jinwoo Shin
Detecting test samples drawn sufficiently far away from the training distribution statistically or adversarially is a fundamental requirement for deploying a good classifier in many real-world machine learning applications. However, deep neural networks with the softmax classifier are known to produce highly overconfident posterior distributions even for such abnormal samples. In this paper, we propose a simple yet effective method for detecting any abnormal samples, which is applicable to any pre-trained softmax neural classifier. We obtain the class conditional Gaussian distributions with respect to (low-and upper-level) features of the deep models under Gaussian discriminant analysis, which result in a confidence score based on the Mahalanobis distance. While most prior methods have been evaluated for detecting either out-of-distribution or adversarial samples, but not both, the proposed method achieves the state-of-the-art performances for both cases in our experiments. Moreover, we found that our proposed method is more robust in harsh cases, e.g., when the training dataset has noisy labels or small number of samples. Finally, we show that the proposed method enjoys broader usage by applying it to class-incremental learning: whenever out-of-distribution samples are detected, our classification rule can incorporate new classes well without further training deep models.
- North America > United States > Michigan (0.04)
- North America > Canada (0.04)
- Europe > Italy > Calabria > Catanzaro Province > Catanzaro (0.04)
AT-CXR: Uncertainty-Aware Agentic Triage for Chest X-rays
Li, Xueyang, Jiang, Mingze, Xu, Gelei, Xia, Jun, Jia, Mengzhao, Chen, Danny, Shi, Yiyu
Agentic AI is advancing rapidly, yet truly autonomous medical-imaging triage, where a system decides when to stop, escalate, or defer under real constraints, remains relatively underexplored. To address this gap, we introduce AT-CXR, an uncertainty-aware agent for chest X-rays. The system estimates per-case confidence and distributional fit, then follows a stepwise policy to issue an automated decision or abstain with a suggested label for human intervention. We evaluate two router designs that share the same inputs and actions: a deterministic rule-based router and an LLM-decided router. Across five-fold evaluation on a balanced subset of NIH ChestX-ray14 dataset, both variants outperform strong zero-shot vision-language models and state-of-the-art supervised classifiers, achieving higher full-coverage accuracy and superior selective-prediction performance, evidenced by a lower area under the risk-coverage curve (AURC) and a lower error rate at high coverage, while operating with lower latency that meets practical clinical constraints. The two routers provide complementary operating points, enabling deployments to prioritize maximal throughput or maximal accuracy. Our code is available at https://github.com/XLIAaron/uncertainty-aware-cxr-agent.
- Information Technology > Artificial Intelligence > Representation & Reasoning (1.00)
- Information Technology > Artificial Intelligence > Natural Language > Large Language Model (1.00)
- Information Technology > Artificial Intelligence > Machine Learning > Performance Analysis > Accuracy (0.34)
- Information Technology > Artificial Intelligence > Machine Learning > Neural Networks > Deep Learning (0.31)
SNAP-UQ: Self-supervised Next-Activation Prediction for Single-Pass Uncertainty in TinyML
Lamaakal, Ismail, Yahyati, Chaymae, Makkaoui, Khalid El, Ouahbi, Ibrahim, Maleh, Yassine
We introduce \textbf{SNAP-UQ}, a single-pass, label-free uncertainty method for TinyML that estimates risk from \emph{depth-wise next-activation prediction}: tiny int8 heads forecast the statistics of the next layer from a compressed view of the previous one, and a lightweight monotone mapper turns the resulting surprisal into an actionable score. The design requires no temporal buffers, auxiliary exits, or repeated forward passes, and adds only a few tens of kilobytes to MCU deployments. Across vision and audio backbones, SNAP-UQ consistently reduces flash and latency relative to early-exit and deep ensembles (typically $\sim$40--60\% smaller and $\sim$25--35\% faster), with competing methods of similar accuracy often exceeding memory limits. In corrupted streams it improves accuracy-drop detection by several AUPRC points and maintains strong failure detection (AUROC $\approx$0.9) in a single pass. Grounding uncertainty in layer-to-layer dynamics yields a practical, resource-efficient basis for on-device monitoring in TinyML.
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- North America > United States > California > Santa Clara County > Palo Alto (0.04)
- Africa > Middle East > Morocco (0.04)
YOLOatr : Deep Learning Based Automatic Target Detection and Localization in Thermal Infrared Imagery
Safdar, Aon, Akram, Usman, Anwar, Waseem, Malik, Basit, Ali, Mian Ibad
Automatic Target Detection (ATD) and Recognition (ATR) from Thermal Infrared (TI) imagery in the defense and surveillance domain is a challenging computer vision (CV) task in comparison to the commercial autonomous vehicle perception domain. Limited datasets, peculiar domain-specific and TI modality-specific challenges, i.e., limited hardware, scale invariance issues due to greater distances, deliberate occlusion by tactical vehicles, lower sensor resolution and resultant lack of structural information in targets, effects of weather, temperature, and time of day variations, and varying target to clutter ratios all result in increased intra-class variability and higher inter-class similarity, making accurate real-time ATR a challenging CV task. Resultantly, contemporary state-of-the-art (SOTA) deep learning architectures underperform in the ATR domain. We propose a modified anchor-based single-stage detector, called YOLOatr, based on a modified YOLOv5s, with optimal modifications to the detection heads, feature fusion in the neck, and a custom augmentation profile. We evaluate the performance of our proposed model on a comprehensive DSIAC MWIR dataset for real-time ATR over both correlated and decorrelated testing protocols. The results demonstrate that our proposed model achieves state-of-the-art ATR performance of up to 99.6%.
- North America > United States (0.28)
- Europe > Sweden > Västmanland County > Västerås (0.04)
- Europe > Ireland > Connaught > County Galway > Galway (0.04)
- Asia > Pakistan > Islamabad Capital Territory > Islamabad (0.04)
Damage detection in an uncertain nonlinear beam based on stochastic Volterra series
Villani, Luis Gustavo Giacon, da Silva, Samuel, Cunha, Americo Jr
The damage detection problem in mechanical systems, using vibration measurements, is commonly called Structural Health Monitoring (SHM). Many tools are able to detect damages by changes in the vibration pattern, mainly, when damages induce nonlinear behavior. However, a more difficult problem is to detect structural variation associated with damage, when the mechanical system has nonlinear behavior even in the reference condition. In these cases, more sophisticated methods are required to detect if the changes in the response are based on some structural variation or changes in the vibration regime, because both can generate nonlinearities. Among the many ways to solve this problem, the use of the Volterra series has several favorable points, because they are a generalization of the linear convolution, allowing the separation of linear and nonlinear contributions by input filtering through the Volterra kernels. On the other hand, the presence of uncertainties in mechanical systems, due to noise, geometric imperfections, manufacturing irregularities, environmental conditions, and others, can also change the responses, becoming more difficult the damage detection procedure. An approach based on a stochastic version of Volterra series is proposed to be used in the detection of a breathing crack in a beam vibrating in a nonlinear regime of motion, even in reference condition (without crack). The system uncertainties are simulated by the variation imposed in the linear stiffness and damping coefficient. The results show, that the nonlinear analysis done, considering the high order Volterra kernels, allows the approach to detect the crack with a small propagation and probability confidence, even in the presence of uncertainties.
- North America > United States > New York > New York County > New York City (0.14)
- South America > Brazil > Rio de Janeiro > Rio de Janeiro (0.04)
- South America > Brazil > São Paulo (0.04)
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Can an unsupervised clustering algorithm reproduce a categorization system?
Castellanos, Nathalia, Desai, Dhruv, Frank, Sebastian, Pasquali, Stefano, Mehta, Dhagash
Peer analysis is a critical component of investment management, often relying on expert-provided categorization systems. These systems' consistency is questioned when they do not align with cohorts from unsupervised clustering algorithms optimized for various metrics. We investigate whether unsupervised clustering can reproduce ground truth classes in a labeled dataset, showing that success depends on feature selection and the chosen distance metric. Using toy datasets and fund categorization as real-world examples we demonstrate that accurately reproducing ground truth classes is challenging. We also highlight the limitations of standard clustering evaluation metrics in identifying the optimal number of clusters relative to the ground truth classes. We then show that if appropriate features are available in the dataset, and a proper distance metric is known (e.g., using a supervised Random Forest-based distance metric learning method), then an unsupervised clustering can indeed reproduce the ground truth classes as distinct clusters.
- North America > United States > New York > New York County > New York City (0.05)
- North America > United States > Massachusetts > Middlesex County > Cambridge (0.04)
- North America > United States > Georgia > Fulton County > Atlanta (0.04)
- (2 more...)