Africa
Explainable deep learning for insights in El Ni\~no and river flows
Liu, Yumin, Duffy, Kate, Dy, Jennifer G., Ganguly, Auroop R.
The El Ni\~no Southern Oscillation (ENSO) is a semi-periodic fluctuation in sea surface temperature (SST) over the tropical central and eastern Pacific Ocean that influences interannual variability in regional hydrology across the world through long-range dependence or teleconnections. Recent research has demonstrated the value of Deep Learning (DL) methods for improving ENSO prediction as well as Complex Networks (CN) for understanding teleconnections. However, gaps in predictive understanding of ENSO-driven river flows include the black box nature of DL, the use of simple ENSO indices to describe a complex phenomenon and translating DL-based ENSO predictions to river flow predictions. Here we show that eXplainable DL (XDL) methods, based on saliency maps, can extract interpretable predictive information contained in global SST and discover SST information regions and dependence structures relevant for river flows which, in tandem with climate network constructions, enable improved predictive understanding. Our results reveal additional information content in global SST beyond ENSO indices, develop understanding of how SSTs influence river flows, and generate improved river flow prediction, including uncertainty estimation. Observations, reanalysis data, and earth system model simulations are used to demonstrate the value of the XDL-CN based methods for future interannual and decadal scale climate projections.
Deep Learning Mental Health Dialogue System
Brocki, Lennart, Dyer, George C., Gลadka, Anna, Chung, Neo Christopher
Mental health counseling remains a major challenge in modern society due to cost, stigma, fear, and unavailability. We posit that generative artificial intelligence (AI) models designed for mental health counseling could help improve outcomes by lowering barriers to access. To this end, we have developed a deep learning (DL) dialogue system called Serena. The system consists of a core generative model and post-processing algorithms. The core generative model is a 2.7 billion parameter Seq2Seq Transformer fine-tuned on thousands of transcripts of person-centered-therapy (PCT) sessions. The series of post-processing algorithms detects contradictions, improves coherency, and removes repetitive answers. Serena is implemented and deployed on \url{https://serena.chat}, which currently offers limited free services. While the dialogue system is capable of responding in a qualitatively empathetic and engaging manner, occasionally it displays hallucination and long-term incoherence. Overall, we demonstrate that a deep learning mental health dialogue system has the potential to provide a low-cost and effective complement to traditional human counselors with less barriers to access.
Multimodal learning with graphs
Ektefaie, Yasha, Dasoulas, George, Noori, Ayush, Farhat, Maha, Zitnik, Marinka
Deep learning on graphs has contributed to breakthroughs in biology [1, 2], chemistry [3, 4], physics [5, 6], and the social sciences [7]. The predominant use of graph neural networks [8] is to learn representations of various graph components--such as nodes, edges, subgraphs, and entire graphs--based on neural message passing strategies. The learned representations are used for downstream tasks, including label prediction via semi-supervised learning [9], self-supervised learning [10], and graph design and generation [11, 12]. In most existing applications, datasets explicitly describe graphs in the form of nodes, edges, and additional information representing contextual knowledge, such as node, edge, and graph attributes. Modeling complex systems requires measurements that describe the same objects from different perspectives, at different scales, or through multiple modalities, such as images, sensor readings, language sequences, and compact mathematical statements. Multimodal learning [13] studies how such heterogeneous, complex descriptors can be optimized to create learning systems that are broadly generalizable, robust to changes in the underlying data distributions, and can train more with less labeled data.
Earthquake Magnitude and b value prediction model using Extreme Learning Machine
Baveja, Gunbir Singh, Singh, Jaspreet
Earthquake prediction has been a challenging research area for many decades, where the future occurrence of this highly uncertain calamity is predicted. In this paper, several parametric and non-parametric features were calculated, where the non-parametric features were calculated using the parametric features. $8$ seismic features were calculated using Gutenberg-Richter law, the total recurrence, and the seismic energy release. Additionally, criterions such as Maximum Relevance and Maximum Redundancy were applied to choose the pertinent features. These features along with others were used as input for an Extreme Learning Machine (ELM) Regression Model. Magnitude and time data of $5$ decades from the Assam-Guwahati region were used to create this model for magnitude prediction. The Testing Accuracy and Testing Speed were computed taking the Root Mean Squared Error (RMSE) as the parameter for evaluating the mode. As confirmed by the results, ELM shows better scalability with much faster training and testing speed (up to a thousand times faster) than traditional Support Vector Machines. The testing RMSE came out to be around $0.097$. To further test the model's robustness -- magnitude-time data from California was used to calculate the seismic indicators which were then fed into an ELM and then tested on the Assam-Guwahati region. The model proves to be robust and can be implemented in early warning systems as it continues to be a major part of Disaster Response and management.
Feature-based Image Matching for Identifying Individual K\=ak\=a
O'Sullivan, Fintan, Escott, Kirita-Rose, Shaw, Rachael C., Lensen, Andrew
This report investigates an unsupervised, feature-based image matching pipeline for the novel application of identifying individual k\=ak\=a. Applied with a similarity network for clustering, this addresses a weakness of current supervised approaches to identifying individual birds which struggle to handle the introduction of new individuals to the population. Our approach uses object localisation to locate k\=ak\=a within images and then extracts local features that are invariant to rotation and scale. These features are matched between images with nearest neighbour matching techniques and mismatch removal to produce a similarity score for image match comparison. The results show that matches obtained via the image matching pipeline achieve high accuracy of true matches. We conclude that feature-based image matching could be used with a similarity network to provide a viable alternative to existing supervised approaches.
A Comprehensive Survey on Heart Sound Analysis in the Deep Learning Era
Ren, Zhao, Chang, Yi, Nguyen, Thanh Tam, Tan, Yang, Qian, Kun, Schuller, Bjรถrn W.
Heart sound auscultation has been demonstrated to be beneficial in clinical usage for early screening of cardiovascular diseases. Due to the high requirement of well-trained professionals for auscultation, automatic auscultation benefiting from signal processing and machine learning can help auxiliary diagnosis and reduce the burdens of training professional clinicians. Nevertheless, classic machine learning is limited to performance improvement in the era of big data. Deep learning has achieved better performance than classic machine learning in many research fields, as it employs more complex model architectures with stronger capability of extracting effective representations. Deep learning has been successfully applied to heart sound analysis in the past years. As most review works about heart sound analysis were given before 2017, the present survey is the first to work on a comprehensive overview to summarise papers on heart sound analysis with deep learning in the past six years 2017--2022. We introduce both classic machine learning and deep learning for comparison, and further offer insights about the advances and future research directions in deep learning for heart sound analysis.
Learning to View: Decision Transformers for Active Object Detection
Ding, Wenhao, Majcherczyk, Nathalie, Deshpande, Mohit, Qi, Xuewei, Zhao, Ding, Madhivanan, Rajasimman, Sen, Arnie
Active perception describes a broad class of techniques that couple planning and perception systems to move the robot in a way to give the robot more information about the environment. In most robotic systems, perception is typically independent of motion planning. For example, traditional object detection is passive: it operates only on the images it receives. However, we have a chance to improve the results if we allow planning to consume detection signals and move the robot to collect views that maximize the quality of the results. In this paper, we use reinforcement learning (RL) methods to control the robot in order to obtain images that maximize the detection quality. Specifically, we propose using a Decision Transformer with online fine-tuning, which first optimizes the policy with a pre-collected expert dataset and then improves the learned policy by exploring better solutions in the environment. We evaluate the performance of proposed method on an interactive dataset collected from an indoor scenario simulator. Experimental results demonstrate that our method outperforms all baselines, including expert policy and pure offline RL methods. We also provide exhaustive analyses of the reward distribution and observation space.
Modeling and Design of Longitudinal and Lateral Control System with a FeedForward Controller for a 4 Wheeled Robot
koudia, Younes El, Tarik, Jarou, Jawad, Abdouni, Idrissi, Sofia El, Nasri, Elmahdi
The work show in this paper progresses through a sequence of physics-based increasing fidelity models that are used to design the robot controllers that respect the limits of the robot capabilities, develop a reference simple controller applicable to a large subset of tracking conditions, which include mostly non-invasive or highly dynamic movements and define path geometry following the control problem and develop both a simple geometric control and a dynamic model predictive control approach. In this paper, we propose for a nonlinear model with disturbance effect, the mathematical modeling of the longitudinal and lateral movements using PID with a feed-forward controller. This study proposes a feedforward controller to eliminate the disturbance effect.
Transcending XAI Algorithm Boundaries through End-User-Inspired Design
Jin, Weina, Fan, Jianyu, Gromala, Diane, Pasquier, Philippe, Li, Xiaoxiao, Hamarneh, Ghassan
The boundaries of existing explainable artificial intelligence (XAI) algorithms are confined to problems grounded in technical users' demand for explainability. This research paradigm disproportionately ignores the larger group of non-technical end users, who have a much higher demand for AI explanations in diverse explanation goals, such as making safer and better decisions and improving users' predicted outcomes. Lacking explainability-focused functional support for end users may hinder the safe and accountable use of AI in high-stakes domains, such as healthcare, criminal justice, finance, and autonomous driving systems. Built upon prior human factor analysis on end users' requirements for XAI, we identify and model four novel XAI technical problems covering the full spectrum from design to the evaluation of XAI algorithms, including edge-case-based reasoning, customizable counterfactual explanation, collapsible decision tree, and the verifiability metric to evaluate XAI utility. Based on these newly-identified research problems, we also discuss open problems in the technical development of user-centered XAI to inspire future research. Our work bridges human-centered XAI with the technical XAI community, and calls for a new research paradigm on the technical development of user-centered XAI for the responsible use of AI in critical tasks.
Ai is the Future: Exploring the Exciting Possibilities of Artificial Intelligence
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