Overview
A Survey of Decision-Theoretic Approaches for Robotic Environmental Monitoring
Sung, Yoonchang, Chen, Zhiang, Das, Jnaneshwar, Tokekar, Pratap
Robotics has dramatically increased our ability to gather data about our environments, creating an opportunity for the robotics and algorithms communities to collaborate on novel solutions to environmental monitoring problems. To understand a taxonomy of problems and methods in this realm, we present the first comprehensive survey of decision-theoretic approaches that enable efficient sampling of various environmental processes. We investigate representations for different environments, followed by a discussion of using these presentations to solve tasks of interest, such as learning, localization, and monitoring. To efficiently implement the tasks, decision-theoretic optimization algorithms consider: (1) where to take measurements from, (2) which tasks to be assigned, (3) what samples to collect, (4) when to collect samples, (5) how to learn environment; and (6) who to communicate. Finally, we summarize our study and present the challenges and opportunities in robotic environmental monitoring.
Deep Bayesian Reinforcement Learning for Spacecraft Proximity Maneuvers and Docking
Du, Desong, Qi, Naiming, Liu, Yanfang, Pan, Wei
In the pursuit of autonomous spacecraft proximity maneuvers and docking(PMD), we introduce a novel Bayesian actor-critic reinforcement learning algorithm to learn a control policy with the stability guarantee. The PMD task is formulated as a Markov decision process that reflects the relative dynamic model, the docking cone and the cost function. Drawing from the principles of Lyapunov theory, we frame the temporal difference learning as a constrained Gaussian process regression problem. This innovative approach allows the state-value function to be expressed as a Lyapunov function, leveraging the Gaussian process and deep kernel learning. We develop a novel Bayesian quadrature policy optimization procedure to analytically compute the policy gradient while integrating Lyapunov-based stability constraints. This integration is pivotal in satisfying the rigorous safety demands of spaceflight missions. The proposed algorithm has been experimentally evaluated on a spacecraft air-bearing testbed and shows impressive and promising performance.
Graph Neural Networks for Power Grid Operational Risk Assessment
Zhang, Yadong, Karve, Pranav M, Mahadevan, Sankaran
In this article, the utility of graph neural network (GNN) surrogates for Monte Carlo (MC) sampling-based risk quantification in daily operations of power grid is investigated. The MC simulation process necessitates solving a large number of optimal power flow (OPF) problems corresponding to the sample values of stochastic grid variables (power demand and renewable generation), which is computationally prohibitive. Computationally inexpensive surrogates of the OPF problem provide an attractive alternative for expedited MC simulation. GNN surrogates are especially suitable due to their superior ability to handle graph-structured data. Therefore, GNN surrogates of OPF problem are trained using supervised learning. They are then used to obtain Monte Carlo (MC) samples of the quantities of interest (operating reserve, transmission line flow) given the (hours-ahead) probabilistic wind generation and load forecast. The utility of GNN surrogates is evaluated by comparing OPF-based and GNN-based grid reliability and risk for IEEE Case118 synthetic grid. It is shown that the GNN surrogates are sufficiently accurate for predicting the (bus-level, branch-level and system-level) grid state and enable fast as well as accurate operational risk quantification for power grids. The article thus develops various tools for fast reliability and risk quantification for real-world power grids using GNNs.
Measuring Adversarial Datasets
Bai, Yuanchen, Huang, Raoyi, Viswanathan, Vijay, Kuo, Tzu-Sheng, Wu, Tongshuang
In the era of widespread public use of AI systems across various domains, ensuring adversarial robustness has become increasingly vital to maintain safety and prevent undesirable errors. Researchers have curated various adversarial datasets (through perturbations) for capturing model deficiencies that cannot be revealed in standard benchmark datasets. However, little is known about how these adversarial examples differ from the original data points, and there is still no methodology to measure the intended and unintended consequences of those adversarial transformations. In this research, we conducted a systematic survey of existing quantifiable metrics that describe text instances in NLP tasks, among dimensions of difficulty, diversity, and disagreement. We selected several current adversarial effect datasets and compared the distributions between the original and their adversarial counterparts. The results provide valuable insights into what makes these datasets more challenging from a metrics perspective and whether they align with underlying assumptions.
Discretizing Numerical Attributes: An Analysis of Human Perceptions
Kaushik, Minakshi, Sharma, Rahul, Draheim, Dirk
Machine learning (ML) has employed various discretization methods to partition numerical attributes into intervals. However, an effective discretization technique remains elusive in many ML applications, such as association rule mining. Moreover, the existing discretization techniques do not reflect best the impact of the independent numerical factor on the dependent numerical target factor. This research aims to establish a benchmark approach for numerical attribute partitioning. We conduct an extensive analysis of human perceptions of partitioning a numerical attribute and compare these perceptions with the results obtained from our two proposed measures. We also examine the perceptions of experts in data science, statistics, and engineering by employing numerical data visualization techniques. The analysis of collected responses reveals that $68.7\%$ of human responses approximately closely align with the values generated by our proposed measures. Based on these findings, our proposed measures may be used as one of the methods for discretizing the numerical attributes.
Machine Learning-Based Tea Leaf Disease Detection: A Comprehensive Review
Ahmed, Faruk, Ahad, Md. Taimur, Emon, Yousuf Rayhan
Tea leaf diseases are a major challenge to agricultural productivity, with far-reaching implications for yield and quality in the tea industry. The rise of machine learning has enabled the development of innovative approaches to combat these diseases. Early detection and diagnosis are crucial for effective crop management. For predicting tea leaf disease, several automated systems have already been developed using different image processing techniques. This paper delivers a systematic review of the literature on machine learning methodologies applied to diagnose tea leaf disease via image classification. It thoroughly evaluates the strengths and constraints of various Vision Transformer models, including Inception Convolutional Vision Transformer (ICVT), GreenViT, PlantXViT, PlantViT, MSCVT, Transfer Learning Model & Vision Transformer (TLMViT), IterationViT, IEM-ViT. Moreover, this paper also reviews models like Dense Convolutional Network (DenseNet), Residual Neural Network (ResNet)-50V2, YOLOv5, YOLOv7, Convolutional Neural Network (CNN), Deep CNN, Non-dominated Sorting Genetic Algorithm (NSGA-II), MobileNetv2, and Lesion-Aware Visual Transformer. These machine-learning models have been tested on various datasets, demonstrating their real-world applicability. This review study not only highlights current progress in the field but also provides valuable insights for future research directions in the machine learning-based detection and classification of tea leaf diseases.
ArAIEval Shared Task: Persuasion Techniques and Disinformation Detection in Arabic Text
Hasanain, Maram, Alam, Firoj, Mubarak, Hamdy, Abdaljalil, Samir, Zaghouani, Wajdi, Nakov, Preslav, Martino, Giovanni Da San, Freihat, Abed Alhakim
We present an overview of the ArAIEval shared task, organized as part of the first ArabicNLP 2023 conference co-located with EMNLP 2023. ArAIEval offers two tasks over Arabic text: (i) persuasion technique detection, focusing on identifying persuasion techniques in tweets and news articles, and (ii) disinformation detection in binary and multiclass setups over tweets. A total of 20 teams participated in the final evaluation phase, with 14 and 16 teams participating in Tasks 1 and 2, respectively. Across both tasks, we observed that fine-tuning transformer models such as AraBERT was at the core of the majority of the participating systems. We provide a description of the task setup, including a description of the dataset construction and the evaluation setup. We further give a brief overview of the participating systems. All datasets and evaluation scripts from the shared task are released to the research community. (https://araieval.gitlab.io/) We hope this will enable further research on these important tasks in Arabic.
TAMPAR: Visual Tampering Detection for Parcel Logistics in Postal Supply Chains
Naumann, Alexander, Hertlein, Felix, Dörr, Laura, Furmans, Kai
Due to the steadily rising amount of valuable goods in supply chains, tampering detection for parcels is becoming increasingly important. In this work, we focus on the use-case last-mile delivery, where only a single RGB image is taken and compared against a reference from an existing database to detect potential appearance changes that indicate tampering. We propose a tampering detection pipeline that utilizes keypoint detection to identify the eight corner points of a parcel. This permits applying a perspective transformation to create normalized fronto-parallel views for each visible parcel side surface. These viewpoint-invariant parcel side surface representations facilitate the identification of signs of tampering on parcels within the supply chain, since they reduce the problem to parcel side surface matching with pair-wise appearance change detection. Experiments with multiple classical and deep learning-based change detection approaches are performed on our newly collected TAMpering detection dataset for PARcels, called TAMPAR. We evaluate keypoint and change detection separately, as well as in a unified system for tampering detection. Our evaluation shows promising results for keypoint (Keypoint AP 75.76) and tampering detection (81% accuracy, F1-Score 0.83) on real images. Furthermore, a sensitivity analysis for tampering types, lens distortion and viewing angles is presented. Code and dataset are available at https://a-nau.github.io/tampar.
LitSumm: Large language models for literature summarisation of non-coding RNAs
Green, Andrew, Ribas, Carlos, Ontiveros-Palacios, Nancy, Petrov, Anton I., Bateman, Alex, Sweeney, Blake
Motivation: Curation of literature in life sciences is a growing challenge. The continued increase in the rate of publication, coupled with the relatively fixed number of curators worldwide presents a major challenge to developers of biomedical knowledgebases. Very few knowledgebases have resources to scale to the whole relevant literature and all have to prioritise their efforts. Results: In this work, we take a first step to alleviating the lack of curator time in RNA science by generating summaries of literature for non-coding RNAs using large language models (LLMs). We demonstrate that high-quality, factually accurate summaries with accurate references can be automatically generated from the literature using a commercial LLM and a chain of prompts and checks. Manual assessment was carried out for a subset of summaries, with the majority being rated extremely high quality. We also applied the most commonly used automated evaluation approaches, finding that they do not correlate with human assessment. Finally, we apply our tool to a selection of over 4,600 ncRNAs and make the generated summaries available via the RNAcentral resource. We conclude that automated literature summarization is feasible with the current generation of LLMs, provided careful prompting and automated checking are applied. Availability: Code used to produce these summaries can be found here: https://github.com/RNAcentral/litscan-summarization and the dataset of contexts and summaries can be found here: https://huggingface.co/datasets/RNAcentral/litsumm-v1. Summaries are also displayed on the RNA report pages in RNAcentral (https://rnacentral.org/)
Exploring Active Learning in Meta-Learning: Enhancing Context Set Labeling
Bae, Wonho, Wang, Jing, Sutherland, Danica J.
Most meta-learning methods assume that the (very small) context set used to establish a new task at test time is passively provided. In some settings, however, it is feasible to actively select which points to label; the potential gain from a careful choice is substantial, but the setting requires major differences from typical active learning setups. We clarify the ways in which active meta-learning can be used to label a context set, depending on which parts of the meta-learning process use active learning. Within this framework, we propose a natural algorithm based on fitting Gaussian mixtures for selecting which points to label; though simple, the algorithm also has theoretical motivation. The proposed algorithm outperforms state-of-the-art active learning methods when used with various meta-learning algorithms across several benchmark datasets. Meta-learning has gained significant prominence as a substitute for traditional "plain" supervised learning tasks, with the aim to adapt or generalize to new tasks given extremely limited data. There has been enormous success compared to learning "from scratch" on each new problem, but could we do even better, with even less data? One major way to improve data-efficiency in standard supervised learning settings is to move to an active learning paradigm, where typically a model can request a small number of labels from a pool of unlabeled data; these are collected, used to further train the model, and the process is repeated. Although each of these lines of research are quite developed, their combination - active meta-learning - has seen comparatively little research attention. Given that both focus on improving data efficiency, it seems very natural to investigate further. How can a meta-learner exploit an active learning setup to learn the best model possible, using only a very small number of labels in its context sets? We are aware of two previous attempts at active selection of context sets in meta-learning: Müller et al. (2022) do so at meta-training time for text classification, while Boney & Ilin (2017) do it at meta-test time in semi-supervised few-shot image classification with ProtoNet (Snell et al., 2017). "Active meta-learning" thus means very different things in their procedures; these approaches are also entirely different from work on active selection of tasks during meta-training (as in Kaddour et al., 2020; Nikoloska & Simeone, 2022; Kumar et al., 2022). Our first contribution is therefore to clarify the different ways in which active learning can be applied to meta-learning, for differing purposes.