🤖 AI Summary
This study addresses the challenges of high noise levels and sparse semantics in raw vessel AIS trajectory data by proposing a context-aware trajectory abstraction framework. The method segments trajectories into voyages and movement segments, integrates multi-source contextual information—including geographic entities, navigational characteristics, and weather conditions—and leverages semantic annotation combined with a large language model (LLM)-guided generation mechanism. This approach enables, for the first time, the production of natural language descriptions with high semantic density driven by heterogeneous contextual cues. The resulting structured and interpretable trajectory representations substantially reduce spatiotemporal complexity, thereby enhancing the usability of maritime data and supporting more effective high-level reasoning.
📝 Abstract
We address the problem of transforming raw vessel trajectory data collected from AIS into structured and semantically enriched representations interpretable by humans and directly usable by machine reasoning systems. We propose a context-aware trajectory abstraction framework that segments noisy AIS sequences into distinct trips each consisting of clean, mobility-annotated episodes. Each episode is further enriched with multi-source contextual information, such as nearby geographic entities, offshore navigation features, and weather conditions. Crucially, such representations can support generation of controlled natural language descriptions using LLMs. We empirically examine the quality of such descriptions generated using several LLMs over AIS data along with open contextual features. By increasing semantic density and reducing spatiotemporal complexity, this abstraction can facilitate downstream analytics and enable integration with LLMs for higher-level maritime reasoning tasks.