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Discovering communities in attributed networks is an important research topic in complex network analysis. Community detection based on multi-objective evolutionary computing (MOEA) models community detection as a multi-objective optimization problem and searches the optimal solutions by simulating the evolution of a biological population. However, the existing multi-objective evolutionary algorithms for community detection faces two challenges: their encoding schemes are designed based on network topology and neglects the information in node attributes; and they are easy to fall into local optimum. In this article, we propose a community detection algorithm empowered by multi-objective evolutionary computing, named ECEVO-MOEA, which conducts edge closeness encoding and embedding vector optimization alternately. On the one hand, the evolution of a biological population is completed by employing a new edge closeness encoding scheme and multiple attribute-aware objective functions. On the other hand, the update of embedding vectors is used to calculate similarity matrix and communities to improve solution quality, avoiding it from early convergence. Experiments on real networks demonstrate that ECEVO-MOEA achieves higher accuracy than the baseline algorithms.

Mobile Crowdsensing (MCS) is a sensing paradigm that enables large-scale smart city applications, such as environmental sensing and traffic monitoring. However, traditional MCS often suffers from performance degradation due to the limited spatiotemporal coverage of collected data. In this context, Sparse MCS has been proposed, which utilizes data inference algorithms to recover full data from sparse data collected by users. However, existing Sparse MCS approaches often overlook spatiotemporal fractures, where no data is observed either for a sensing subarea across all sensing time slots (temporal fracture), or for a sensing time slot in all sensing subarea (spatial fracture). Such spatiotemporal fractures pose great challenges to the data inference algorithms, as it is difficult to capture the complex spatiotemporal correlations of the sensing data from very limited observations. To address this issue, we propose a Graph- and Attention-based Matrix Completion (GAMC) method for the spatiotemporal fracture data inference problem in Sparse MCS. Specifically, we first pre-fill the general missing values using the classical Matrix Factorization (MF) technique. Then, we propose a neural network architecture based on Graph Attention Networks (GAT) and Transformer to capture complex spatiotemporal dependencies in the sensing data. Finally, we recover the complete data with a projection layer. We conduct extensive experiments on three real-world urban sensing datasets. The experimental results show the effectiveness of the proposed method.

The intricate and dynamic nature of eye movements serves as a window into the realms of cognition, emotion, and physiological responses. Event detection, in turn, is instrumental in the precise recognition and categorization of these diverse eye movements. Deep learning methods have recently been applied to event detection, yielding promising results. However, the intrinsic multi-scale attributes of events have often been overlooked in existing approaches. To address this, we introduce “GazeUNet”, a novel network based on U-Net and Bi-GRU, which classifies gaze samples into three categories: fixation, saccade, and post-saccadic oscillations. Firstly, multi-scale spatial features are captured using a U-Net model, and then a hierarchical bidirectional gated recurrent unit (Bi-GRU) is employed to extract temporal correlations, followed by classification through fully connected layers. Our results, derived from the analysis of three publicly available datasets, consistently showcase the superiority of the proposed model compared with other state-of-the-art methods across all categories.

Sparse crowdsensing collects data from a subset of the sensing area and infers data for unsensed areas, reducing data collection costs. Previous works have primarily focused on independently collecting and inferring single types of data. However, real-world scenarios often involve multiple types of data that can complement each other by providing missing spatiotemporal distribution information. In this paper, we fully consider both intra-data correlations among data of the same type and inter-data correlations among data of different types, enabling collaborative execution of various tasks. In addition, we enhance the adaptability in practical application scenarios by utilizing real-time collected sparse data to guide task execution. For this purpose, we propose a multi-task adaptive budgeting framework for online sparse crowdsensing, called MTAB-SC. This framework consists of three parts: training data updating, data inference, and data collection. First, we propose a multi-task data updating method to keep models up-to-date. Second, we design a data inference network for multi-task data joint inference. Finally, to allocate suitable budgets for each task and facilitate collaborative data collection across multiple tasks, we propose an Adaptive Budgeting for Collaborative Data Collection model (AB-CoDC). The effectiveness of our proposals is demonstrated through extensive experiments on two real-world datasets.

This article presents a limited amplitude-disturbance observer (LADOB) as a means to counteract transient disturbance dynamics in a nonlinear control system with backlash. The core principle of this method involves directly constraining the linear output amplitude of the observer using a saturation function. This approach yields a high-bandwidth disturbance observer while ensuring the stability. By virtue of its rapid response, the LADOB effectively mitigates backlash spikes induced by speed reversal. Additionally, the saturation function within the LADOB control system addresses limit cycle oscillations stemming from backlash dynamics. An investigation is conducted to determine the optimal balance between stability and antidisturbance performance by examining the relationship between the saturation threshold and the system's bandwidth. Experimental validation is carried out on a belt-drive turntable, effectively demonstrating the efficacy of the proposed method in attenuating nonlinear backlash.

This article is concerned with the exact controllability of a linear stochastic game-based control system (SGBCS) with time-variant random coefficients. Some necessary conditions and sufficient conditions for the exact terminal controllability of the SGBCS are obtained. Then, it is proved that the exact controllability of the SGBCS, the nonsingularity of a generalized version of the Gramian matrix, the validity of an observability inequality for the adjoint equation, and the unique solvability of a family of minimization problems are all equivalent. An admissible control for the regulator is constructed in closed form, which can steer the macrostate from any existing initial vector to any desired terminal random variable.