Predicting remaining useful life (RUL) plays a crucial role in the prognostics and health management of industrial systems that involve a variety of interrelated sensors. Given a constant stream of time-series sensory data from such systems, deep learning (DL) models have risen to prominence at identifying complex, nonlinear temporal dependencies in these data. In addition to the temporal dependencies of individual sensors, spatial dependencies emerge as important correlations among these sensors, which can be naturally modeled by a temporal graph that describes time-varying spatial relationships. However, the majority of existing studies have relied on capturing discrete snapshots of this temporal graph, a coarse-grained approach that leads to a loss of temporal information. Moreover, given the variety of heterogeneous sensors, it becomes vital that such inherent heterogeneity is leveraged for RUL prediction in temporal sensor graphs. To capture the nuances of the temporal and spatial relationships and heterogeneous characteristics in an interconnected graph of sensors, we introduce a novel model named temporal and heterogeneous graph neural networks (THGNNs). Specifically, THGNN aggregates historical data from neighboring nodes to accurately capture the temporal dynamics and spatial correlations within the stream of sensor data in a fine-grained manner. Moreover, the model leverages feature-wise linear modulation (FiLM) to address the diversity of sensor types, significantly improving the model’s capacity to learn the heterogeneity in the data sources. Finally, we have validated the effectiveness of our approach through comprehensive experiments. Our empirical findings demonstrate significant advancements on the N-CMAPSS dataset, achieving improvements of up to 19.2% and 31.6% in terms of two different evaluation metrics over state-of-the-art methods.

Most of the existing distributed feature selection schemes neglect how good the subsets are that are mapped to the computational nodes, which causes a waste of time and hardware resources. A distributed integrated feature selection scheme (DIFS) with Subset Quality Evaluation (SQE) is proposed. SQE studies the relevance between the quality of a subset and the number of selected features from this subset, which helps shorten the feature selection time efficiently. We have given the implementation of our scheme for the Column Subset Selection (CSS) problem. We integrate a CSS algorithm in DIFS and information entropy as the SQE metric. We prove that the speedup of DIFS can reach m^3 compared to the centralized algorithm in ideal situations where m is the number of computational nodes, and give a well bounded approximation guarantee of the solution for CSS problem. Extensive experiments on eight data sets are used to verify the performance of scheme. Experiments results demonstrate the effectiveness of SQE and the impressive speedup DIFS can achieve. Although there is a slight increase of the reconstruction error value in some situations. Additional experiments of classification tasks reveal that the performance of DIFS is better than existing state-of-the-art distributed algorithms.

In vehicular cooperative perception (CP), numerous resource allocation strategies have been proposed to enhance urban autonomous driving. However, existing studies often overlook the competition between self-perception and cooperative perception, where degrading a ground vehicle’s (GV’s) self-perception may introduce safety risks and reduce passenger comfort. Moreover, air-ground cooperation—which can improve sensing precision, reduce task execution delay, and enhance CP service availability—has received limited attention. It is worth noting that autonomous aerial vehicles are unavailable for cooperative perception during the recharging process.To address these issues, this paper investigates on-demand scheduling strategy in air-ground cooperative perception. At the millisecond timescale, resource competition is considered in real-time sensing, communication, and computation (SC$^{2}$) resource allocation. At the minute timescale, the idle flying period between consecutive tasks is utilized for autonomous aerial vehicles’ recharging through attachment to GVs along the route. Specifically, we first develop a model that captures the mutual influence between autonomous aerial vehicles and GVs on perception performance under resource constraints. Then, a mixed-timescale solution is proposed: at the small timescale, a multi-agent deep reinforcement learning algorithm with gradient-free projection and auxiliary supervision is designed to schedule SC² resources; at the large timescale, a Hungarian-based algorithm is employed to control autonomous aerial vehicles’ recharging. Simulation results show that the proposed approach outperforms benchmark schemes by reducing task execution delay and energy consumption, and enhancing CP service availability, while satisfying sensing precision, GV safety, and passenger comfort requirements.