Wang-Chien Lee

Guo-Wei Wong, Ming-Chuan Yang, Shou-De Lin et al.

In enterprise environments, multiple Advanced Persistent Threat (APT) campaigns often unfold concurrently, producing audit logs in which attack techniques across actors (sources) are interleaved over time. This setting naturally gives rise to an Unknown-K Interleaved Sequence Demixing (UKISD) problem: recovering multiple latent campaigns from an interleaved technique sequence while jointly inferring their number and technique-level assignments. Existing approaches, ranging from statistical pattern mining to provenance-based analysis, typically assume single-campaign settings or rely on rigid heuristics, limiting their effectiveness under realistic conditions involving overlapping campaigns, shared techniques, and variable execution lengths. We present Topic-Guided Consistency Modeling (TGCM), a generative disentanglement framework to tackle the UKSID problem. TGCM leverages Consistency Models to learn a direct inverse mapping from interleaved multi-campaign observations to structured single-campaign sequences in a single inference step. To favor semantically coherent attack chains, TGCM incorporates a topic-guided prior derived from MITRE ATT\&CK narratives, providing high-level tactical constraints during decomposition. We evaluate TGCM on synthetic datasets, established mixed datasets, and incident traces from DARPA TC-E3 and TC-E5, comparing against 15 representative baselines spanning pattern mining, deep learning, and LLM-based methods. Results indicate improved separation robustness over baselines under heavy interleaving and technique sharing, and show that TGCM generalizes zero-shot to a naturally interleaved in-the-wild benchmark (DARPA TC-E5) without retraining.

Zhao Liu, Wei Liu, Huajie Zhu et al.

The next Point-of-Interest (POI) recommendation task aims to predict users' next destinations based on their historical movement data and plays a key role in location-based services and personalized applications. Accurate next POI recommendation depends on effectively modeling geographic information and POI transition relations, which are crucial for capturing spatial dependencies and user movement patterns. While Large Language Models (LLMs) exhibit strong capabilities in semantic understanding and contextual reasoning, applying them to spatial tasks like next POI recommendation remains challenging. First, the infrequent nature of specific GPS coordinates makes it difficult for LLMs to model precise spatial contexts. Second, the lack of knowledge about POI transitions limits their ability to capture potential POI-POI relationships. To address these issues, we propose GA-LLM (Geography-Aware Large Language Model), a novel framework that enhances LLMs with two specialized components. The Geographic Coordinate Injection Module (GCIM) transforms GPS coordinates into spatial representations using hierarchical and Fourier-based positional encoding, enabling the model to understand geographic features from multiple perspectives. The POI Alignment Module (PAM) incorporates POI transition relations into the LLM's semantic space, allowing it to infer global POI relationships and generalize to unseen POIs. Experiments on three real-world datasets demonstrate the state-of-the-art performance of GA-LLM.

Weilin Cong, William Wang, Wang-Chien Lee

Despite the great success object detection and segmentation models have achieved in recognizing individual objects in images, performance on cognitive tasks such as image caption, semantic image retrieval, and visual QA is far from satisfactory. To achieve better performance on these cognitive tasks, merely recognizing individual object instances is insufficient. Instead, the interactions between object instances need to be captured in order to facilitate reasoning and understanding of the visual scenes in an image. Scene graph, a graph representation of images that captures object instances and their relationships, offers a comprehensive understanding of an image. However, existing techniques on scene graph generation fail to distinguish subjects and objects in the visual scenes of images and thus do not perform well with real-world datasets where exist ambiguous object instances. In this work, we propose a novel scene graph generation model for predicting object instances and its corresponding relationships in an image. Our model, SG-CRF, learns the sequential order of subject and object in a relationship triplet, and the semantic compatibility of object instance nodes and relationship nodes in a scene graph efficiently. Experiments empirically show that SG-CRF outperforms the state-of-the-art methods, on three different datasets, i.e., CLEVR, VRD, and Visual Genome, raising the Recall@100 from 24.99% to 49.95%, from 41.92% to 50.47%, and from 54.69% to 54.77%, respectively.