In electroencephalogram (EEG)-based emotion recognition, the applicability of most current models is limited by inter-subject variability and emotion complexity. This study proposes a multi-task adversarial domain adaptation (MTADA) network to enhance cross-subject emotion recognition performance. The model first employs a domain matching strategy to select the source domain that best matches the target domain. Then, adversarial domain adaptation is used to learn the difference between source and target domains, and a fine-grained joint domain discriminator is constructed to align them by incorporating category information. At the same time, a multi-task learning mechanism is utilized to learn the intrinsic relationships between different emotions and predict multiple emotions simultaneously. We conducted comprehensive experiments on two public datasets, DEAP and FACED. On DEAP, the average accuracies for valence, arousal and dominance are 76.39%, 69.74% and 68.26%, respectively. On FACED, the average accuracies for valence and arousal are 78.90% and 77.95%. When using the subject from DEAP as the source domain to predict the subjects in FACED, the accuracies for valence and arousal are 61.07% and 60.82%. These results show that our MTADA model improves cross-subject emotion recognition and outperforms most state-of-the-art methods, which may provide new approach for EEG-based emotion brain-computer interface systems.

The clinical assessment of patients with disorders of consciousness (DoC) still faces challenges due to the lack of objective and accurate methods. To address this issue, this paper proposes a multi-scale convolutional feature adaptive weighting (MC-FAW) fusion network, which aims to integrate multi-scale electroencephalogram (EEG) functional connectivity features to improve the classification performance of consciousness states. Based on resting-state EEG data from 15 healthy controls (HC), 15 patients in a minimally conscious state (MCS), and 17 patients in a vegetative state (VS), the MC-FAW model effectively captures multi-scale features of brain neural activity and dynamically weights these features to achieve a more comprehensive and accurate assessment of consciousness. The classification results demonstrate that this method achieves classification accuracies of 96.54% for distinguishing HC from MCS, 98.47% for HC from VS, and 85.25% for MCS from VS. These results indicate that our method has the potential to improve the objectivity and accuracy of clinical diagnosis, thereby providing important support for clinical decision-making.

Confidential virtual machines (CVM) use trusted hardware to encrypt data being processed in memory to prevent unauthorized access. Applications can be migrated to CVM without changes, i.e., lift and shift, to handle sensitive workloads securely in public clouds. AMD Secure Encrypted Virtualization (SEV) is one of the prominent technologies that provides hardware support for CVM. In this paper, we investigate various system operations, including CPU, memory, and disk and network I/O, to understand the performance overheads of SEV-supported CVMs. Our findings indicate that memory and I/O-intensive workloads can incur significant overhead. We then study the performance implications of running unmodified database applications, specifically Cock-roachDB, on CVMs by examining typical data access patterns of OLTP and OLAP workloads. A notable performance overhead of up to 18% is observed for TPC-C workload running on multinode database clusters, and an overhead of up to 13% is observed for TPC-H workload running on single-node database instances. The non-negligible overhead suggests the potential and necessity for database optimizations with respect to CVM, particularly for time-sensitive workloads. We offer a glimpse of the effect that CVM overhead can have in query planning using a simple join query: the optimal join algorithm becomes suboptimal on CVM, along with discussion of potential optimizations for reducing CVM overhead in the realm of database applications.

Ergonomic risk assessment (ERA) is commonly used to identify and analyze postures that are detrimental to the health of workers in industrial workplaces, which is vital to prevent work-related musculoskeletal disorders (WMSDs). Among the automatic approaches, algorithms based on graph convolutional networks (GCNs) have shown promising results in ERA using skeleton sequence as input. However, previous GCN-based methods still have certain limitations. First, the separated modeling of spatial and temporal information and the manually pre-defined topology of graph may restrict the representation diversity of the networks. Additionally, RNN-based temporal modeling often incurs high computational costs and fails to capture long-range temporal dependencies, thereby reducing flexibility in describing long videos. To overcome these challenges, in this study, we propose an attention-based adaptive spatial–temporal graph convolutional network (AAST-GCN), aiming to achieve effective and efficient action representation for ERA in long video. First, we employ an alternate modeling strategy to effectively capture the spatial–temporal information, and propose an improved adaptive adjacency matrix scheme to learn various coordination and relations of body-joints, thus enhancing the flexibility to model diverse postures. Furthermore, we introduce an efficient multi-scale temporal convolutional network as a replacement for RNN-based algorithms, enabling the network to extract various granularities of temporal features. Moreover, to make the network focuses on more valuable information, we employ a spatial–temporal interaction attention (STIA) module. Finally, the aforementioned modules are aggregated within a multi-task learning framework, with the action segmentation serving as the auxiliary task to further improve the accuracy of ERA. We conducted the ergonomic risk assessment on the UW-IOM and TUM Kitchen datasets using our network. Extensive experiments conducted on the most popular datasets UW-IOM and TUM Kitchen demonstrated that our proposed AAST-GCN outperforms other GCN-based methods. Ablation studies and visualization also prove the effectiveness of the individual sub-modules.

Secure collaborative analytics (SCA) enables the processing of analytical SQL queries across data from multiple owners, even when direct data sharing is not possible. While traditional SCA provides strong privacy through data-oblivious methods, the significant overhead has limited its practical use. Recent SCA variants that allow controlled leakages under differential privacy (DP) strike balance between privacy and efficiency but still face challenges like unbounded privacy loss, costly execution plan, and lossy processing. To address these challenges, we introduce SPECIAL, the first SCA system that simultaneously ensures bounded privacy loss, advanced query planning, and lossless processing. SPECIAL employs a novel synopsis-assisted secure processing model , where a one-time privacy cost is used to generate private synopses from owner data. These synopses enable SPECIAL to estimate compaction sizes for secure operations (e.g., filter, join) and index encrypted data without additional privacy loss. These estimates and indexes can be prepared before runtime, enabling efficient query planning and accurate cost estimations. By leveraging one-sided noise mechanisms and private upper bound techniques, SPECIAL guarantees lossless processing for complex queries (e.g., multi-join). Our comprehensive benchmarks demonstrate that SPECIAL outperforms state-of-the-art SCAs, with up to 80× faster query times, 900× smaller memory usage for complex queries, and up to 89× reduced privacy loss in continual processing.

Most cloud service providers offer limited data privacy guarantees, discouraging clients from using them for managing their sensitive data. Cloud providers may use servers with Trusted Execution Environments (TEEs) to protect outsourced data, while supporting remote querying. However, TEEs may leak access patterns and allow communication volume attacks, enabling an honest-but-curious cloud provider to learn sensitive information. Oblivious algorithms can be used to completely hide data access patterns, but their high overhead could render them impractical. To alleviate the latter, the notion of Differential Obliviousness (DO) has been recently proposed. DO applies differential privacy (DP) on access patterns while hiding the communication volume of intermediate and final results; it does so by trading some level of privacy for efficiency. We present Doquet: D ifferentially O blivious Range and Join Que ries with Private Data Struc t ures, a framework for DO outsourced database systems. Doquet is the first approach that supports private data structures, indices, selection, foreign key join, many-to-many join, and their composition select-join in a realistic TEE setting, even when the accesses to the private memory can be eavesdropped on by the adversary. We prove that the algorithms in Doquet satisfy differential obliviousness. Furthermore, we implemented Doquet and tested it on a machine having a second generation of Intel SGX (TEE); the results show that Doquet offers up to an order of magnitude speedup in comparison with other fully oblivious and differentially oblivious approaches.

Numerous static taint analysis techniques have recently been proposed for identifying information flows in mobile applications. These techniques are often optimized and evaluated on a set of synthetic benchmarks, which makes the comparison results difficult to generalize. Moreover, the techniques are commonly compared under different configuration setups, rendering the comparisons inaccurate. In this paper, we provide a large, controlled, and independent comparison of the three most prominent static taint analysis tools:FlowDroid,Amandroid, andDroidSafe. We align the configuration setup for the tools and evaluate them on both a set of common benchmarks and on real applications from the Google Play app store. We further evaluate the effectiveness of additional reflection handling mechanism implemented byDroidRA, applying it to each of the evaluated tools. We compare the results of our analysis to the results reported in previous studies, identify main reasons for inaccuracy in existing tools, and provide suggestions for future research.

Internet Protocol TV (IPTV) normally has the advantage of providing far more TV channels than the traditional TV services, while as the other side of the coin it has the problem of information overload. Users of IPTV usually have difficulties finding channels matching their interests. In this paper, using a large IPTV dataset, we analyze channel zapping behaviors of IPTV users and discover various patterns that can be used to generate more accurate channel zapping recommendations. Based on user behavior analysis, we develop several base and fusion recommender systems that generate in real-time a short list of channels for users to consider whenever they want to switch channels. A deep neural network model that consists of a “Recommender System Attention (RS Attention)” module and a “Channel Attention” module capturing the static and dynamic user switching behaviors is also developed to further improve the recommendation accuracy. Evaluation on the IPTV dataset demonstrates that our fusion recommender can achieve 41% hit ratio with only three candidate channels, and our attention neural network model further pushes it up to 45%. Our recommender systems only take as input user channel zapping sequences, and can be easily adopted by IPTV systems with low data and computation overheads.

In the field of data science, utility-driven data mining has become an emergent intelligent technique with wide applications. The existing utility mining algorithms usually discover all the patterns satisfying a given minimum utility threshold. However, a huge number of return results is not intuitive, not interpretable, and not easy for users to understand. Besides, it is often difficult and time-consuming for users to set a proper minimum utility threshold that is quite sensitive to the mining results. To address these issues, the problem of top-k high-utility itemset mining has been studied. In this paper, we present an efficient algorithm (named TopHUI) for finding top-k high-utility itemsets from transactional database that contains both positive and negative utility. This algorithm utilizes the positive-and-negative utility-list (PNU-list) to store the compress information, including positive, negative, and remaining utility. Besides, several threshold raising strategies and pruning strategies are proposed to prune the search space. Finally, some extensive experiments were conducted to evaluate the performance of the proposed TopHUI algorithm on both real-life and synthetic datasets, particularly in terms of effectiveness and efficiency.

It is widely known that there is a lot of useful information hidden in big data, and it is prevalent for individuals to mine crucial information for utilization in many real-world applications. To find patterns that can represent the supporting transaction, a recent study was conducted to mine high-utility occupancy patterns whose contribution to the utility of the entire transaction is greater than a certain value. Moreover, in realistic applications, patterns may not exist in transactions but be connected to an existence probability. In this paper, a novel algorithm, called High Utility-Occupancy Pattern Mining in Uncertain databases (UHUOPM), is proposed. The patterns found by this algorithm are called Potential High Utility Occupancy Patterns (PHUOPs). To reduce memory cost and time consumption and to prune the search space in the algorithm as mentioned above, probability-utility-occupancy list (PUO-list) and probability-frequency-utility table (PFU-table) are used. Finally, substantial experiments were conducted to evaluate the performance of proposed UHUOPM algorithm on both real-life and synthetic datasets.

While previous work on smartphone (un)locking has revealed real world usage patterns, several aspects still need to be explored. In this paper, we fill one of these knowledge gaps: the interplay between age and smartphone authentication behavior. To do this, we performed a two-month long field study (N = 134). Our results indicate that there are indeed significant differences across age. For instance, younger participants were more likely to use biometric unlocking mechanisms and older participants relied more on auto locks.

Numerous static analysis techniques have recently been proposed for identifying information flows in mobile applications. These techniques are compared to each other, usually on a set of syntactic benchmarks. Yet, configurations used for such comparisons are rarely described. Our experience shows that tools are often compared under different setup, rendering the comparisons irreproducible and largely inaccurate. In this paper, we provide a large, controlled, and independent comparison of the three most prominent static analysis tools: FlowDroid combined with IccTA, Amandroid, and DroidSafe. We evaluate all tools using common configuration setup and the same set of benchmark applications. We compare the results of our analysis to the results reported in previous studies, identify main reasons for inaccuracy in existing tools, and provide suggestions for future research.