We present MCGS (Markov Chain Gaussian Splatting), a novel approach for high-fidelity dynamic scene reconstruction via combining Markov chain and 3D Gaussian splatting. Our method addresses the critical challenge of artifact-free temporal consistency in dynamic neural rendering. By integrating a Markov chain-based deformation network with multi-head temporal attention, MCGS effectively captures motion patterns and temporal dependencies, producing more accurate and stable 3D representations over time. The key innovations include: (1) a Markov Deform Network that models state transitions while preserving temporal coherence, (2) a temporal attention mechanism that adaptively weights historical states within a sliding window, and (3) strategic noise injection during training to enhance model robustness and generalization. Experiments on representative dynamic scene datasets demonstrate that MCGS outperforms previous methods in both visual quality and temporal coherence, while maintaining competitive rendering speed and efficiency. These results suggest the practical applicability of our approach to real-world dynamic scene understanding and synthesis.

Point cloud tasks have recently benefited from Mamba-based architecture, which leverage state space modeling to achieve strong performance. Previous studies have primarily focused on network design while overlooking the importance of position encoding and relying on coarse-grained geometric feature aggregation. The former leads to semantic ambiguity due to inconsistent spatial relationships, while the latter results in geometric feature dispersion by overlooking fine-grained local geometric details. To tackle the above problem, we propose a novel framework, PointMC, including Multi-view Consistent Learnable Position Encoding (MCLPE) and Center-Global Feature Fusion (CGFF), to provide semantically coherent positional guidance for inter-patch and enable fine-grained geometric structure aggregation within intra-patch regions. Specifically, the proposed MCLPE module is inspired by a spatial structure modeling mechanism guided by physical constraints, leverages multi-view virtual reconstruction and a learnable strategy to dynamically constrain spatial relationships along patch boundaries, thereby enhancing the semantic consistency and representational clarity across inter-patch regions. Furthermore, considering the lack of local structural information within each patch, the CGFF module employs a dual-guidance mechanism based on center and global structures to effectively promote the aggregation of local geometric features. Extensive experiments on multiple benchmark datasets validate the effectiveness of PointMC, consistently outperforming existing state-of-the-art methods, and demonstrating superior capability in capturing both inter-patch semantic consistency and intra-patch geometric details.

Point cloud completion aims to infer complete point clouds based on partial 3D point cloud inputs. Various previous methods apply coarse-to-fine strategy networks for generating complete point clouds. However, such methods are not only relatively time-consuming but also cannot provide representative complete shape features based on partial inputs. In this paper, a novel feature alignment fast point cloud completion network (FACNet) is proposed to directly and efficiently generate the detailed shapes of objects. FACNet aligns high-dimensional feature distributions of both partial and complete point clouds to maintain global information about the complete shape. During its decoding process, the local features from the partial point cloud are incorporated along with the maintained global information to ensure complete and time-saving generation of the complete point cloud. Experimental results show that FACNet outperforms the state-of-the-art on PCN, Completion3D, and MVP datasets, and achieves competitive performance on ShapeNet-55 and KITTI datasets. Moreover, FACNet and a simplified version, FACNet-slight, achieve a significant speedup of 3–10 times over other state-of-the-art methods.

Pre-trained models (PTMs) with parameter-efficient fine-tuning (PEFT) techniques have been extensively utilized in class-incremental learning (CIL) scenarios. However, they still remain susceptible to performance degradation as the individual PEFT module operates as an independent learning entity during the incremental process. To this end, this work proposes a novel class-incremental collaborative adapter experts (CICAE) model, which incorporates multiple adapters operating collaboratively to facilitate CIL. Specifically, our model primarily consists of two phases. Initially, multiple adapters are employed to establish a multi-expert system aimed at acquiring diverse incremental knowledge. Through the collaborative knowledge sharing (CKS) mechanism, the expertise of each adapter expert is transferable, promoting collaborative development and mutual advancement. Subsequently, with the category prototype distributions, collaborative classifier alignment (CCA) is proposed to further align the classifiers with the representation space in a cooperative manner. Extensive experiments on CIL benchmarks validate the superior performance of our model.

Modeling large scale and rare-interaction users are the two major challenges in recommender systems, which derives big gaps between researches and applications. Facing to millions or even billions of users, it is hard to store and leverage personalized preferences with a user embedding matrix in real scenarios. And many researches pay attention to users with rich histories, while users with only one or several interactions are the biggest part in real systems. Previous studies make efforts to handle one of the above issues but rarely tackle efficiency and cold-start problems together.

Most recommendation algorithms mainly make use of user history interactions in the model, while these methods often suffer from the cold-start problem (user/item has no history information). On the other sides, content features help on cold-start scenarios for modeling new users or items. So it is essential to utilize content features to enhance different recommendation models. To take full advantage of content features, feature interactions such as cross features are used by some models and outperform than using raw features. However, in real-world systems, many content features are incomplete, e.g., we may know the occupation and gender of a user, but the values of other features (location, interests, etc.) are missing. This missing-feature-value (MFV) problem is harmful to the model performance, especially for models that rely heavily on rich feature interactions. Unfortunately, this problem has not been well studied previously.