Compressed sensing (CS), breaking the constriction of Shannon-Nyquist sampling theorem, is a very promising data acquisition technique in the era of multimedia big data. However, the high complexity of CS reconstruction algorithm is a big trouble for endusers who are hardly provided with great computing power. The combination of CS and cloud has the potential of freeing endusers from the resource constraint by cleverly transforming computational workload from the local cilent to the cloud platform. As a result, the low-complexity encoding virtue of CS is fully leveraged in the resource-constrained sensing devices but its highcomplexity decoding problem is effectively addressed in cloud. It seems to be perfect but privacy and security concerns are ignored. In this paper, a secure outsourcing scheme for CS reconstruction service is proposed. Experimental results and security analyses demonstrate that the proposed scheme can restrict malicious access, verify the integrity of the recovered data, and resist brute-force attack, ciphertext-only attack, and plaintext attack.

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Abstract Study Objectives The frequency of cortical arousals is an indicator of sleep quality. Additionally, cortical arousals are used to identify hypopneic events. However, it is inconvenient to record electroencephalogram (EEG) data during home sleep testing. Fortunately, most cortical arousal events are associated with autonomic nervous system activity that could be observed on an electrocardiography (ECG) signal. ECG data have lower noise and are easier to record at home than EEG. In this study, we developed a deep learning-based cortical arousal detection algorithm that uses a single-lead ECG to detect arousal during sleep. Methods This study included 1,547 polysomnography records that met study inclusion criteria and were selected from the Multi-Ethnic Study of Atherosclerosis database. We developed an end-to-end deep learning model consisting of convolutional neural networks and recurrent neural networks which: (1) accepted varying length physiological data; (2) directly extracted features from the raw ECG signal; (3) captured long-range dependencies in the physiological data; and (4) produced arousal probability in 1-s resolution. Results We evaluated the model on a test set (n = 311). The model achieved a gross area under precision-recall curve score of 0.62 and a gross area under receiver operating characteristic curve score of 0.93. Conclusion This study demonstrated the end-to-end deep learning approach with a single-lead ECG has the potential to be used to accurately detect arousals in home sleep tests.

With continuously shrinking technology, reliability issues such as Negative Bias Temperature Instability (NBTI) has resulted in considerable degradation of device performance, and eventually the short mean-time-to-failure (MTTF) of the whole multicore system. This article proposes a new workload balancing scheme based on device-level fractional NBTI model to balance the workload among active cores while relaxing stressed ones. Starting with NBTI-induced threshold voltage degradation, we define a concept of Capacity Rate (CR) as an indication of one core's ability to accept workload. Capacity rate captures core's performance variability in terms of delay and power metrics under the impact of NBTI aging. The proposed workload balancing framework employs the capacity rates as workload constraints, applies a Dynamic Zoning (DZ) algorithm to group cores into zones to process task flows, and then uses Dynamic Task Scheduling (DTS) to allocate tasks in each zone with balanced workload and minimum communication cost. Experimental results on a 64-core system show that by allowing a small part of the cores to relax over a short time period, the proposed methodology improves multicore system yield (percentage of core failures) by 20%, while extending MTTF by 30% with insignificant degradation in performance (less than 3%).

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