Abstract Deep learning has achieved remarkable success in various domains including time series analysis, computer vision and natural language processing. However, high computational and memory demands of state-of-the-art architectures pose challenges for deployment in resource-limited environments. Knowledge Distillation (KD) addresses this by transferring knowledge from a large teacher model to a smaller, more efficient student model while maintaining competitive performance. In this work, we investigate the effectiveness of KD for Time Series Classification (TSC) across three architectures: the classical Fully Convolutional Network (FCN), the convolutional Inception model and the transformer-based ConvTran model. We evaluate our approach on UCR Archive, the largest benchmark repository of time series datasets, by modifying architectural components such as convolutional filters, Inception modules and attention heads across the three architectures. Our results consistently show that KD most effectively benefits student models of intermediate complexity across all three architectures, with the distilled FCN student reducing parameters by a factor of 38, the distilled Inception student achieving nearly the same performance as the teacher with 42% fewer parameters and the distilled ConvTran student with 2 attention heads showing the most significant improvement through distillation. To encourage further research and reproducibility, we provide our implementation at https://github.com/MSD-IRIMAS/KD-4-TSC.

Time series classification has achieved significant advancements through deep learning models; however, these models often suffer from high complexity and computational costs. To address these challenges while maintaining effectiveness, we introduce COCALITE, an innovative hybrid model that combines the efficient LITE model with an augmented version incorporating Catch22 features during training. COCALITE operates with only 4.7% of the parameters of the state-of-the-art Inception model, significantly reducing computational overhead. By integrating these complementary approaches, COCALITE leverages both effective feature engineering and deep learning techniques to enhance classification accuracy. Our extensive evaluation across 128 datasets from the UCR archive demonstrates that COCALITE achieves competitive performance, offering a compelling solution for resource-constrained environments.

International audience

In self-navigation problems for autonomous vehicles, the variability of environmental conditions, complex scenes with vehicles and pedestrians, and the high-dimensional or real-time nature of tasks make segmentation challenging. Sensor fusion can representatively improve performances. Thus, this work highlights a late fusion concept used for semantic segmentation tasks in such perception systems. It is based on two approaches for merging information coming from two neural networks, one trained for camera data and one for LiDAR frames. The first approach involves fusing probabilities along with calculating partial conflicts and redistributing data. The second technique focuses on making individual decisions based on sources and fusing them later with weighted Shannon entropies. The two segmentation models are trained and evaluated on a particular KITTI semantic dataset. In the realm of multi-class segmentation tasks, the two fusion techniques are compared and evaluated with illustrative examples. Intersection over union metric and quality of decision are computed to assess the performance of each methodology.

Deep learning models have been shown to be a powerful solution for Time Series Classification (TSC). State-of-the-art architectures, while conducting promising results on the UCR archive, present a high number of trainable parameters. This can lead to long training with a high CO2, Power consumption and possible increase in the number of FLoat-point Operation Per Second (FLOPS). In this paper, we present a new architecture for TSC, the Light Inception with boosTing tEchnique (LITE) with only 2.34% of the state-of-the-art model InceptionTime’s number of parameters, while preserving performance. This architecture, with only 9, 814 trainable parameters due to the usage of DepthWise Separable Convolutions (DWSC), is boosted by three techniques: multiplexing, custom filters, and dilated convolution. The LITE architecture, trained on the UCR, is 2.78 times faster than InceptionTime and consumes 2.79 times less CO2 and Power.

In recent years, there has been an increasing interest in Deep Learning models for time series classification. In this field, state-of-the-art architectures rely on convolution neural networks that learn one dimensional filters in order to capture patterns allowing to discriminate between the different classes. These filters are randomly initialized and modified throughout model training. In this paper, we explore the creation of handcrafted (non learned) filters in order to capture specific patterns in a time series. We propose a set of filters whose values are fixed and not modified during the training step. Our goal with these filters is to captures pecific patterns in a time series (increase, decrease, peaks) and study the relevance of adding such filters to existing architectures ranging from simple architecture (Fully Convolutional Network (FNC)) to state-of-the-art architecture (InceptionTime). Experiments reveal that adding our manually created filters increase the prediction accuracy on a majority of the 128 datasets of the UCR Archive. They also show that handcrafted filters and learned filters are complementary to obtain the best preforming models. This work is the first step in proposing a catalog of generic and fixed filters that could be useful in a large range of applications to improve deep models accuracy for time series classification.

XML is currently a well established and widely used document format. It is used as a core data container in collaborative writing suites and other modern information architectures. The extraction and analysis of differences between two XML document versions is an attractive topic, and has already been tackled by several research groups. The goal of this study is to compare 12 existing state-of-the-art and commercial XML diff algorithms by applying them to JATS documents in order to extract and evaluate changes between two versions of the same academic article. Understanding changes between two article versions is important not only regarding data, but also semantics. Change information consumers in our case are editorial teams, and thus they are more generally interested in change semantics than in the exact data changes. The existing algorithms are evaluated on the following aspects: their edit detection suitability for both text and tree changes, execution speed, memory usage and delta file size. The evaluation process is supported by a Python tool available on Github.