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1. Time-Aware Subgroup Matrix Decomposition: Imputing Missing Data Using Forecasting Events

   Yang, X. Yuan (January 2018, IEEE International Conference on Big Data)

   Deep neural network models, especially Long Short Term Memory (LSTM), have shown great success in analyzing Electronic Health Records (EHRs) due to their ability to capture temporal dependencies in time series data. When applying the deep learning models to EHRs, we are generally confronted with two major challenges: high rate of missingness and time irregularity. Motivated by the original PACIFIER framework which utilized matrix decomposition for data imputation, we applied and further extended it by including three components: forecasting future events, a time-aware mechanism, and a subgroup basis approach. We evaluated the proposed framework with real-world EHRs which consists of 52,919 visits and 4,224,567 events on a task of early prediction of septic shock. We compared our work against multiple baselines including the original PACIFIER using both LSTM and Time-aware LSTM (T-LSTM). Experimental results showed that our proposed framework significantly outperformed all competitive baseline approaches. More importantly, the extracted interpretative latent patterns from subgroups could shed some lights for clinicians to discover the progression of septic shock patients. 

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2. Supervised Deep Learning Models for Detecting GPS Spoofing Attacks on Unmanned Aerial Vehicles

   https://doi.org/10.1109/eIT57321.2023.10187274  

   Khoei, Tala Talaei; Aissou, Ghilas; Al Shamaileh, Khair; Devabhaktuni, Vijaya Kumar; Kaabouch, Naima (October 2023, IEEE International Conference on Electro Information Technology (eIT))

   Unmanned Aerial Networks (UAVs) are prone to several cyber-attacks, including Global Positioning Spoofing attacks. For this purpose, numerous studies have been conducted to detect, classify, and mitigate these attacks, using Artificial Intelligence techniques; however, most of these studies provided techniques with low detection, high misdetection, and high bias rates. To fill this gap, in this paper, we propose three supervised deep learning techniques, namely Deep Neural Network, U Neural Network, and Long Short Term Memory. These models are evaluated in terms of Accuracy, Detection Rate, Misdetection Rate, False Alarm Rate, Training Time per Sample, Prediction Time, and Memory Size. The simulation results indicated that the U Neural Network outperforms other models with an accuracy of 98.80%, a probability of detection of 98.85%, a misdetection of 1.15%, a false alarm of 1.8%, a training time per sample of 0.22 seconds, a prediction time of 0.2 seconds, and a memory size of 199.87 MiB. In addition, these results depicted that the Long Short-Term Memory model provides the lowest performance among other models for detecting these attacks on UAVs. 

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3. A Fast and Accurate Myocardial Infarction Detector

   https://doi.org/10.1109/CSCI51800.2020.00147  

   Martin, Harold; Izquierdo, Walter; Morar, Ulyana; Cabrerizo, Mercedes; Cabrera, Anastasio; Adjouadi, Malek (December 2020, 2020 International Conference on Computational Science and Computational Intelligence (CSCI))

   null (Ed.)

   We propose a novel pipeline for the real-time detection of myocardial infarction from a single heartbeat of a 12-lead electrocardiograms. We do so by merging a real-time R-spike detection algorithm with a deep learning Long-Short Term Memory (LSTM) network-based classifier. A comparative assessment of the classification performance of the resulting system is performed and provided. The proposed algorithm achieves an inter-patient classification accuracy of 95.76% (with a 95% Confidence Interval (CI) of ±2.4%), a recall of 96.67% (±2.4% 95% CI), specificity of 93.64% (±5.7% 95% CI), and the average J-Score is 90.31% (±6.2% 95% CI). These state-of-the-art myocardial infarction detection metrics are extremely promising and could pave the wave for the early detection of myocardial infarctions. This high accuracy is achieved with a processing time of 40 milliseconds, which is most appropriate for online classification as the time between fast heartbeats is around 300 milliseconds. 

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4. ATTAIN: Attention-based Time-Aware LSTM Networks for Disease Progression Modeling.

   Zhang, Y. (January 2019, In Proceedings of the 28th International Joint Conference on Artificial Intelligence (IJCAI-2019), pp. 4369-4375, Macao, China.)

   Modeling patient disease progression using Electronic Health Records (EHRs) is critical to assist clinical decision making. Long-Short Term Memory (LSTM) is an effective model to handle sequential data, such as EHRs, but it encounters two major limitations when applied to EHRs: it is unable to interpret the prediction results and it ignores the irregular time intervals between consecutive events. To tackle these limitations, we propose an attention-based time-aware LSTM Networks (ATTAIN), to improve the interpretability of LSTM and to identify the critical previous events for current diagnosis by modeling the inherent time irregularity. We validate ATTAIN on modeling the progression of an extremely challenging disease, septic shock, by using real-world EHRs. Our results demonstrate that the proposed framework outperforms the state-of-the-art models such as RETAIN and T-LSTM. Also, the generated interpretative time-aware attention weights shed some lights on the progression behaviors of septic shock. 

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5. Short-Term Long-Term Compute-In-Memory Architecture: A Hybrid Spin/CMOS Approach Supporting Intrinsic Consolidation

   https://doi.org/10.1109/JXCDC.2020.2983450  

   Sheikhfaal, Shadi; DeMara, Ronald F. (March 2020, IEEE Journal on Exploratory Solid-State Computational Devices and Circuits)

   Biological memory structures impart enormous retention capacity while automatically providing vital functions for chronological information management and update resolution of domain and episodic knowledge. A crucial requirement for hardware realization of such cortical operations found in biology is to first design both Short-Term Memory (STM) and Long-Term Memory (LTM). Herein, these memory features are realized via a beyond-CMOS based learning approach derived from the repeated input information and retrieval of the encoded data. We first propose a new binary STM-LTM architecture with composite synapse of Spin Hall Effect-driven Magnetic Tunnel Junction (SHE-MTJ) and capacitive memory bit-cell to mimic the behavior of biological synapses. This STM-LTM platform realizes the memory potentiation through a continual update process using STM-to-LTM transfer, which is applied to Neural Networks based on the established capacitive crossbar. We then propose a hardware-enabled and customized STM-LTM transition algorithm for the platform considering the real hardware parameters. We validate the functionality of the design using SPICE simulations that show the proposed synapse has the potential of reaching ~30.2pJ energy consumption for STM-to-LTM transfer and 65pJ during STM programming. We further analyze the correlation between energy, array size, and STM-to-LTM threshold utilizing the MNIST dataset. 

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