Graph neural networks (GNNs) have emerged as the mainstream paradigm for graph representation learning due to their effective message aggregation. However, this advantage also amplifies biases inherent in graph topology, raising fairness concerns. Existing fairness-aware GNNs provide satisfactory performance on fairness metrics such as Statistical Parity and Equal Opportunity while maintaining acceptable accuracy trade-offs. Unfortunately, we observe that this pursuit of fairness metrics neglects the GNN's ability to predict negative labels, which renders their predications with extremely high False Positive Rates (FPRs), resulting in negative effects in high-risk scenarios. To this end, we advocate that classification performance should be carefully calibrated while improving fairness, rather than simply constraining accuracy loss. Furthermore, we propose Fair GNN via Structural Entropy (FairGSE), a novel framework that maximizes two-dimensional structural entropy (2D-SE) to improve fairness without neglecting false positives. Experiments on several real-world datasets show FairGSE reduces FPR by 39% vs. state-of-the-art fairness-aware GNNs, with comparable fairness improvement.

Recently, data-driven approaches have brought both opportunities and challenges for Inertial Navigation Systems. In this paper, we propose a novel data-driven method which is composed of cascading orientation and translation estimation with IMU-only measurements. For robust orientation estimation, we combine a CNN-based neural network with an EKF to eliminate orientation errors caused by sensor noises. We additionally propose a hybrid CNN-Transformer-based neural network which exploits both spatial and long-term temporal information to regress accurate translations. Specifically, we conduct detailed evaluations on datasets acquired by iPhone and Android devices. The result demonstrates that our method outperforms state-of-the-art methods in both orientation and translation errors.

This paper proposes a multi-sensor fusion system, named ONavi, that fuses WiFi and IMU to provide an accurate positioning service on smartphones in indoor environments. In this system, a hybrid CNN-Transformer-based neural network is proposed for our Pedestrian Dead Reckoning(PDR), which outperforms existing state-of-the-art methods. Additionally, in our data-driven WiFi positioning module, instead of pure RSSI based WiFi feature, a “Fusion BSSID-RSSI” feature is proposed, which significantly improves positioning accuracy. Eventually, we use a loosely coupled optimization-based framework to fuse the aforementioned positioning results. Quantitative evaluations demonstrate that ONavi is capable of achieving outstanding performance of positioning estimation in real indoor environment.

Co-location pattern mining refers to discovering neighboring relationships of spatial features distributed in geographic space. With the rapid growth of spatial datasets, the usefulness of co-location patterns is strongly limited by the large number of discovered patterns containing multiple redundancies. To address this problem, in this article, we propose a novel approach for discovering the super participation index-closed (SPI-closed) co-location patterns which are a newly proposed lossless condensed representation of co-location patterns by considering distributions of the spatial instances. In the proposed approach, first, a linear-time method is designed to generate complete and correct neighboring cliques using extended neighboring relationships. Based on these cliques, a hash structure is then constructed to store the distributions of the co-location patterns in a condensed way. Finally, using this hash structure, the SPI-closed co-location patterns (SCPs) are efficiently discovered even if the prevalence threshold is changed, while similar approaches have to restart their mining processes. To confirm the efficiency of the proposed method, we compared its performance with similar approaches in the literature on multiple real and synthetic spatial datasets. The experiments confirm that our new approach is more efficient, effective, and flexible than similar approaches.

In datacenter networks, bandwidth-demanding elephant flows without deadline and delay-sensitive mice flows with strict deadline coexist. They compete with each other for limited network resources, and the effective scheduling of such mix-flows is extremely challenging. We propose a deep reinforcement learning with private link approach (DRL-PLink), which combines the software-defined network and deep reinforcement learning (DRL) to schedule mix-flows. DRL-PLink divides the link bandwidth and establishes some corresponding private-links for different types of flows to isolate them such that the competition among different types of flows can decrease accordingly. DRL is used to adaptively and intelligently allocate bandwidth resources for these private-links. Furthermore, to improve the scheduling policy, DRL-PLink introduces the novel clipped double Q-learning, exploration with noise, and prioritized experience replay technology for DDPG to address function approximation error, to induce lager and more randomness for exploration, as well as more effective and efficient experience replay in DRL respectively. The experiment results under actual datacenter network workloads (including Web search and data mining workload) indicate that DRL-PLink can effectively schedule mix-flows at a small system overhead. Compared with ECMP, pFabric, and Karuna, the average flow completion time of DRL-PLink decreased by 77.79%, 65.61%, and 23.34% respectively, when the deadline meet rate is increased by 16.27%, 0.02%, and 0.836% respectively. Additionally, DRL-PLink can also well achieve load balance between paths.

In software-defined datacenter networks, there are bandwidth-demanding elephant flows without deadline and delay-sensitive mice flows with strict deadline. They compete with each other for limited network resources, and how to effectively schedule such mix-flow is a huge challenge. We propose DRL-PLink (deep reinforcement learning with private link) that combines software-defined network and deep reinforcement learning (DRL) to schedule mix-flow. It divides the link bandwidth and establishes some corresponding private links for different types of flows respectively to isolate them. DRL is used to adaptively allocate bandwidth resources for these private links. Furthermore, DRL-PLink introduces Clipped Double Q-learning and parameter exploration NoisyNet technology to improve the scheduling policy for overestimated value estimates and action exploration problems in DRL. The simulation results show that DRL-PLink can effectively schedule mix-flow. Compared with ECMP and pFabric, the average flow completion time of DRL-PLink has decreased by 68.87% and 52.18% respectively. At the same time, it maintains a high deadline meet rate (>96.6%) close to pFabric and Karuna very much.