Publication Date
Spring 2026
Degree Type
Master's Project
Degree Name
Master of Science in Computer Science (MSCS)
Department
Computer Science
First Advisor
Amith Kamath Belman
Second Advisor
Fabio Di Troia
Third Advisor
Genya Ishigaki
Keywords
Object Detection, YOLO, Attention Mechanisms, Anchor Assignment, Out-of-Distribution Detection, Traffic Sign Detection
Abstract
In this work, we built a YOLO11-nano architecture fully from scratch without pretrained weights or the Ultralytics framework. We introduced C2DSA (a dual-stream attention module), SAAL (Size-Adaptive Anchor-Assignment Logic), and a contrastive OOD scoring head. C2DSA increased the mAP@0.5 from 0.746 to 0.764 by adding spatial-only self-attention and channel-wise cross-covariance. The OOD head achieves a 0.997 AUROC at very low computational and inference cost. We validated these improvements on the German Traffic Sign Detection Benchmark (GTSDB). These enhancements, combined with test-time augmentation, raised the baseline mAP@0.5 from 0.492 to 0.792 (+61% relative). Crucially, we further validated these enhancements by integrating them with the official pretrained Ultralytics YOLO11-nano through module injection. All of these improvements combined with TTA raised mAP@0.5 from 0.956 to 0.979 (+2.5%).
Recommended Citation
Bhatnagar, Ashwabh, "Exploring Architectural Enhancements for YOLO Object Detection: Dual-Stream Attention, Size-Adaptive Assignment, and OOD Awareness" (2026). Master's Projects. 1826.
DOI: https://doi.org/10.31979/etd.akrx-4js8
https://scholarworks.sjsu.edu/etd_projects/1826