Different from the traditional semi-supervised learning paradigm that is constrained by the close-world assumption, Generalized Category Discovery (GCD) presumes that the unlabeled dataset contains new categories not appearing in the labeled set, and aims to not only classify old categories but also discover new categories in the unlabeled data. Existing studies on GCD typically devote to transferring the general knowledge from the self-supervised pretrained model to the target GCD task via some fine-tuning strategies, such as partial tuning and prompt learning. Nevertheless, these fine-tuning methods fail to make a sound balance between the generalization capacity of pretrained backbone and the adaptability to the GCD task. To fill this gap, in this paper, we propose a novel adapter-tuning-based method named AdaptGCD, which is the first work to introduce the adapter tuning into the GCD task and provides some key insights expected to enlighten future research. Furthermore, considering the discrepancy of supervision information between the old and new classes, a multi-expert adapter structure equipped with a route assignment constraint is elaborately devised, such that the data from old and new classes are separated into different expert groups. Extensive experiments are conducted on 7 widely-used datasets. The remarkable performance improvements highlight the efficacy of our proposal and it can be also combined with other advanced methods like SPTNet for further enhancement.

Survival analysis is extensively employed to analyze the probability of the event of interest, particularly in the medical field. Most current research treats patients as isolated entities, neglecting the complex associations among them, which leads to underutilization of valuable information. Recently, several studies address this limitation by incorporating patient graph structures. However, these approaches generally overlook two critical issues: 1) the exploration of heterogeneous inter-patient relationships, and 2) flexible and scalable inductive inference for test samples. To overcome these challenges, this study introduces a novel framework, Multiplex Graph Guided Deep Survival Analysis (MGG-Surv). Specifically, we employ multiplex patient graphs to capture comprehensive inter-patient associative information. Furthermore, we propose a teacher-student dual network architecture, where the teacher network encodes multiplex graphs, and the learned graph knowledge is transferred to the student network via a unidirectional connection termed Graph-Guided Distillation. The student network integrates this graph knowledge to predict survival outcomes without requiring the patient graphs. These innovative designs facilitate comprehensive integration of inter-patient relationships while achieving flexible and scalable graph-free inference. Experiments on four datasets, encompass-ing both single and competing risks, demonstrate the superior performance of our framework.

Despite recent progress in semi-supervised learning (SSL), its scalability remains limited in realistic scenarios where unseen classes may appear in the unlabeled data. To address this challenge, open-world SSL (OWSSL) is proposed in recent years and attracts much attention. One core difficulty in OWSSL is to enhance the representative ability for unlabeled samples, especially for those in novel classes. More recently, several works introduce contrastive learning into OWSSL and achieve impressive performance. However, they mainly focus on conducting contrastive learning solely in either feature or prediction spaces, while ignoring the thorough exploration of information potentials in dual spaces. In this study, we propose a novel method to handle OWSSL tasks via dual-space contrastive learning (DSCL). DSCL contains two modules: intraspace contrastive learning and interspace contrastive learning. In the intraspace module, we bridge the two spaces with a learnable classifier and impose contrastive learning in the dual spaces, such that the category discriminative information could be effectively utilized to improve the representative ability. In interspace module, to further enhance the utilization of complementary information from dual spaces, we introduce neighborhood information from feature space to enhance predictive learning and meanwhile utilize the cluster structure from the prediction spaces to improve intraclass compactness of the features. Compared with state-of-the-art competitors, the proposed DSCL achieves superior performance on the popular benchmarks, i.e., CIFAR100, Imagenet100, CIFAR10, CUB-200, and Scar.

Classification of nonprecipitation echoes of radar is an inevitable step in radar-based precipitation estimation. Among nonprecipitation echoes, clear air echoes are specifically difficult to distinguish for their similarity to precipitation echoes. This letter aims to conduct a pixelwise classification of clear air echoes for image sequences of the radar reflectivity. We propose the Static and Motion streams Network (SMNet) to simultaneously utilize the static and motion features. SMNet realizes capturing the spatiotemporal characteristics while maintaining the details of the current frame via a fusion structure and a novel training method. For feature fusion, the static and motion streams are concatenated. Then, for model training, we adopt a dynamic weight assignment strategy to further extract rich information. Finally, we validate our method on an S-band single-polarization radar in Beijing, China, from May to September 2018. The results demonstrate that the overall performance of SMNet is superior to other competitors.