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Detection of Animal Movement from Weather Radar using Self-Supervised Learning

arXiv.org Artificial Intelligence

Detecting flying animals (e.g., birds, bats, and insects) using weather radar helps gain insights into animal movement and migration patterns, aids in management efforts (such as biosecurity) and enhances our understanding of the ecosystem.The conventional approach to detecting animals in weather radar involves thresholding: defining and applying thresholds for the radar variables, based on expert opinion. More recently, Deep Learning approaches have been shown to provide improved performance in detection. However, obtaining sufficient labelled weather radar data for flying animals to build learning-based models is time-consuming and labor-intensive. To address the challenge of data labelling, we propose a self-supervised learning method for detecting animal movement. In our proposed method, we pre-train our model on a large dataset with noisy labels produced by a threshold approach. The key advantage is that the pre-trained dataset size is limited only by the number of radar images available. We then fine-tune the model on a small human-labelled dataset. Our experiments on Australian weather radar data for waterbird segmentation show that the proposed method outperforms the current state-of-the art approach by 43.53% in the dice co-efficient statistic.


Scalable Transformer for High Dimensional Multivariate Time Series Forecasting

arXiv.org Artificial Intelligence

Deep models for Multivariate Time Series (MTS) forecasting have recently demonstrated significant success. Channel-dependent models capture complex dependencies that channel-independent models cannot capture. However, the number of channels in real-world applications outpaces the capabilities of existing channel-dependent models, and contrary to common expectations, some models underperform the channel-independent models in handling high-dimensional data, which raises questions about the performance of channel-dependent models. To address this, our study first investigates the reasons behind the suboptimal performance of these channel-dependent models on high-dimensional MTS data. Our analysis reveals that two primary issues lie in the introduced noise from unrelated series that increases the difficulty of capturing the crucial inter-channel dependencies, and challenges in training strategies due to high-dimensional data. To address these issues, we propose STHD, the Scalable Transformer for High-Dimensional Multivariate Time Series Forecasting. STHD has three components: a) Relation Matrix Sparsity that limits the noise introduced and alleviates the memory issue; b) ReIndex applied as a training strategy to enable a more flexible batch size setting and increase the diversity of training data; and c) Transformer that handles 2-D inputs and captures channel dependencies. These components jointly enable STHD to manage the high-dimensional MTS while maintaining computational feasibility. Furthermore, experimental results show STHD's considerable improvement on three high-dimensional datasets: Crime-Chicago, Wiki-People, and Traffic. The source code and dataset are publicly available https://github.com/xinzzzhou/ScalableTransformer4HighDimensionMTSF.git.


Ensemble BERT: A student social network text sentiment classification model based on ensemble learning and BERT architecture

arXiv.org Artificial Intelligence

The mental health assessment of middle school students has always been one of the focuses in the field of education. This paper introduces a new ensemble learning network based on BERT, employing the concept of enhancing model performance by integrating multiple classifiers. We trained a range of BERT-based learners, which combined using the majority voting method. We collect social network text data of middle school students through China's Weibo and apply the method to the task of classifying emotional tendencies in middle school students' social network texts. Experimental results suggest that the ensemble learning network has a better performance than the base model and the performance of the ensemble learning model, consisting of three single-layer BERT models, is barely the same as a three-layer BERT model but requires 11.58% more training time. Therefore, in terms of balancing prediction effect and efficiency, the deeper BERT network should be preferred for training. However, for interpretability, network ensembles can provide acceptable solutions.


Towards Explainable Network Intrusion Detection using Large Language Models

arXiv.org Artificial Intelligence

Large Language Models (LLMs) have revolutionised natural language processing tasks, particularly as chat agents. However, their applicability to threat detection problems remains unclear. This paper examines the feasibility of employing LLMs as a Network Intrusion Detection System (NIDS), despite their high computational requirements, primarily for the sake of explainability. Furthermore, considerable resources have been invested in developing LLMs, and they may offer utility for NIDS. Current state-of-the-art NIDS rely on artificial benchmarking datasets, resulting in skewed performance when applied to real-world networking environments. Therefore, we compare the GPT-4 and LLama3 models against traditional architectures and transformer-based models to assess their ability to detect malicious NetFlows without depending on artificially skewed datasets, but solely on their vast pre-trained acquired knowledge. Our results reveal that, although LLMs struggle with precise attack detection, they hold significant potential for a path towards explainable NIDS. Our preliminary exploration shows that LLMs are unfit for the detection of Malicious NetFlows. Most promisingly, however, these exhibit significant potential as complementary agents in NIDS, particularly in providing explanations and aiding in threat response when integrated with Retrieval Augmented Generation (RAG) and function calling capabilities.


FTF-ER: Feature-Topology Fusion-Based Experience Replay Method for Continual Graph Learning

arXiv.org Artificial Intelligence

Continual graph learning (CGL) is an important and challenging task that aims to extend static GNNs to dynamic task flow scenarios. As one of the mainstream CGL methods, the experience replay (ER) method receives widespread attention due to its superior performance. However, existing ER methods focus on identifying samples by feature significance or topological relevance, which limits their utilization of comprehensive graph data. In addition, the topology-based ER methods only consider local topological information and add neighboring nodes to the buffer, which ignores the global topological information and increases memory overhead. To bridge these gaps, we propose a novel method called Feature-Topology Fusion-based Experience Replay (FTF-ER) to effectively mitigate the catastrophic forgetting issue with enhanced efficiency. Specifically, from an overall perspective to maximize the utilization of the entire graph data, we propose a highly complementary approach including both feature and global topological information, which can significantly improve the effectiveness of the sampled nodes. Moreover, to further utilize global topological information, we propose Hodge Potential Score (HPS) as a novel module to calculate the topological importance of nodes. HPS derives a global node ranking via Hodge decomposition on graphs, providing more accurate global topological information compared to neighbor sampling. By excluding neighbor sampling, HPS significantly reduces buffer storage costs for acquiring topological information and simultaneously decreases training time. Compared with state-of-the-art methods, FTF-ER achieves a significant improvement of 3.6% in AA and 7.1% in AF on the OGB-Arxiv dataset, demonstrating its superior performance in the class-incremental learning setting.


Know Your Limits: A Survey of Abstention in Large Language Models

arXiv.org Artificial Intelligence

But questions of Large language models (LLMs) have demonstrated human values and the answerability of the query generalization capabilities across NLP tasks such itself are difficult to model in terms of model confidence as question answering (QA) (Wei et al., 2022; (Yang et al., 2023). Chowdhery et al., 2022), abstractive summarization (Zhang et al., 2023a), and dialogue generation While prior work demonstrates the potential of (Yi et al., 2024). But these models are also unreliable, abstention in enhancing model safety and reliability having a tendency to "hallucinate" false information (Varshney et al., 2023; Wang et al., 2024c; in their responses (Ji et al., 2023b), generate Zhang et al., 2024a), the study of abstention has overly certain or authoritative responses (Zhou also been constrained to specific QA tasks. This et al., 2024b), answer with incomplete information task-specific approach limits the broader applicability (Zhou et al., 2023b), or produce harmful or of abstention strategies across the diverse dangerous responses (Anwar et al., 2024). In these range of scenarios encountered by general-purpose situations, the model should ideally abstain: to chatbots engaging in open-domain interactions.


Human Speech Perception in Noise: Can Large Language Models Paraphrase to Improve It?

arXiv.org Artificial Intelligence

Large Language Models (LLMs) can generate text by transferring style attributes like formality resulting in formal or informal text. However, instructing LLMs to generate text that when spoken, is more intelligible in an acoustically difficult environment, is an under-explored topic. We conduct the first study to evaluate LLMs on a novel task of generating acoustically intelligible paraphrases for better human speech perception in noise. Our experiments in English demonstrated that with standard prompting, LLMs struggle to control the non-textual attribute, i.e., acoustic intelligibility, while efficiently capturing the desired textual attributes like semantic equivalence. To remedy this issue, we propose a simple prompting approach, prompt-and-select, which generates paraphrases by decoupling the desired textual and non-textual attributes in the text generation pipeline. Our approach resulted in a 40% relative improvement in human speech perception, by paraphrasing utterances that are highly distorted in a listening condition with babble noise at a signal-to-noise ratio (SNR) -5 dB. This study reveals the limitation of LLMs in capturing non-textual attributes, and our proposed method showcases the potential of using LLMs for better human speech perception in noise.


pyBregMan: A Python library for Bregman Manifolds

arXiv.org Artificial Intelligence

A Bregman manifold is a synonym for a dually flat space in information geometry which admits as a canonical divergence a Bregman divergence. Bregman manifolds are induced by smooth strictly convex functions like the cumulant or partition functions of regular exponential families, the negative entropy of mixture families, or the characteristic functions of regular cones just to list a few such convex Bregman generators. We describe the design of pyBregMan, a library which implements generic operations on Bregman manifolds and instantiate several common Bregman manifolds used in information sciences. At the core of the library is the notion of Legendre-Fenchel duality inducing a canonical pair of dual potential functions and dual Bregman divergences. The library also implements the Fisher-Rao manifolds of categorical/multinomial distributions and multivariate normal distributions. To demonstrate the use of the pyBregMan kernel manipulating those Bregman and Fisher-Rao manifolds, the library also provides several core algorithms for various applications in statistics, machine learning, information fusion, and so on.


A Guide to Similarity Measures

arXiv.org Artificial Intelligence

Similarity measures play a central role in various data science application domains for a wide assortment of tasks. This guide describes a comprehensive set of prevalent similarity measures to serve both non-experts and professional. Non-experts that wish to understand the motivation for a measure as well as how to use it may find a friendly and detailed exposition of the formulas of the measures, whereas experts may find a glance to the principles of designing similarity measures and ideas for a better way to measure similarity for their desired task in a given application domain.


Advancing Multimodal Large Language Models with Quantization-Aware Scale Learning for Efficient Adaptation

arXiv.org Artificial Intelligence

This paper presents the first study to explore the potential of parameter The remarkable performance of large language models (LLMs) has quantization for multimodal large language models to alleviate been well-established in recent literature [4, 9, 35, 36, 39], sparking the significant resource constraint encountered during visionlanguage a growing interest in the development of multimodal large language instruction tuning. We introduce a Quantization-aware models (MLLMs) [2, 3, 5, 24, 28, 32, 42]. This burgeoning field has Scale LeArning method based on multimodal Warmup, termed QS-led to substantial progress in a wide array of vision-language (VL) LAW. This method is grounded in two key innovations: (1) The tasks. To accomplish this, contemporary MLLMs primarily utilize learning of group-wise scale factors for quantized LLM weights multimodal instruction following examples for VL instruction tuning to mitigate the quantization error arising from activation outliers and adopt modular architectures [2, 21, 24, 28] to transform and achieve more effective vision-language instruction tuning; (2) visual features into the word embedding space of the LLM. This The implementation of a multimodal warmup that progressively innovative approach enables LLMs to execute multimodal tasks in integrates linguistic and multimodal training samples, thereby preventing an autoregressive fashion. One notable example of this technique is overfitting of the quantized model to multimodal data while LLaVA [24], which employs a linear projection layer to bridge the ensuring stable adaptation of multimodal large language models to gap between the visual encoder and the LLM.