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Robustness Certification of Visual Perception Models via Camera Motion Smoothing

arXiv.org Artificial Intelligence

A vast literature shows that the learning-based visual perception model is sensitive to adversarial noises, but few works consider the robustness of robotic perception models under widely-existing camera motion perturbations. To this end, we study the robustness of the visual perception model under camera motion perturbations to investigate the influence of camera motion on robotic perception. Specifically, we propose a motion smoothing technique for arbitrary image classification models, whose robustness under camera motion perturbations could be certified. The proposed robustness certification framework based on camera motion smoothing provides tight and scalable robustness guarantees for visual perception modules so that they are applicable to wide robotic applications. As far as we are aware, this is the first work to provide robustness certification for the deep perception module against camera motions, which improves the trustworthiness of robotic perception. A realistic indoor robotic dataset with a dense point cloud map for the entire room, MetaRoom, is introduced for the challenging certifiable robust perception task. We conduct extensive experiments to validate the certification approach via motion smoothing against camera motion perturbations. Our framework guarantees the certified accuracy of 81.7% against camera translation perturbation along depth direction within -0.1m ~ 0.1m. We also validate the effectiveness of our method on the real-world robot by conducting hardware experiments on the robotic arm with an eye-in-hand camera. The code is available at https://github.com/HanjiangHu/camera-motion-smoothing.


Radial Basis Function Approximation with Distributively Stored Data on Spheres

arXiv.org Artificial Intelligence

Noname manuscript No. (will be inserted by the editor) Abstract This paper proposes a distributed weighted regularized lea st squares algorithm (DWRLS) with radial basis functions to tackle spherical data that are stored acr oss numerous local servers and cannot be shared with each other. Via developing a novel integral operator approa ch based on spherical quadrature rules, we succeed in deriving optimal approximation rates for DWRLS and theor etically demonstrate that DWRLS performs similarly as running a weighted regularized least squares algo rithm on the whole data stored on a large enough machine. This interesting finding implies that distributed learning is capable of sufficiently exploiting potential values of distributively stored spherical data, even thoug h local servers cannot access the whole data. Keywords Distributed learning Scattered data approximation Sphere Integral operator 1 Introduction In geophysics, solar system, climate prediction, environm ent governance and meteorology, and image rendering, samples formed as input-output pairs are collected over spheres [13, 15, 49], such as the surface of the earth and the direction of radiance. Due to the storage bo ttleneck and data privacy, these spherical data are often distributively stored across numerous computati onal servers.


GAC: A Deep Reinforcement Learning Model Toward User Incentivization in Unknown Social Networks

arXiv.org Artificial Intelligence

In recent years, many applications have deployed incentive mechanisms to promote users' attention and engagement. Most incentive mechanisms determine specific incentive values based on users' attributes (e.g., preferences), while such information is unavailable in many real-world applications. Meanwhile, due to budget restrictions, realizing successful incentivization for all users can be challenging to complete. In this light, we consider leveraging social influence to maximize the incentivization result. We can directly incentivize influential users to affect more users, so the cost of incentivizing these users can be decreased. However, identifying influential users in a social network requires complete information about influence strength among users, which is impractical to acquire in real-world situations. In this research, we propose an end-to-end reinforcement learning-based framework, called Geometric Actor-Critic (GAC), to tackle the abovementioned problem. The proposed approach can realize effective incentive allocation without having prior knowledge about users' attributes. Three real-world social network datasets have been adopted in the experiments to evaluate the performance of GAC. The experimental results indicate that GAC can learn and apply effective incentive allocation policies in unknown social networks and outperform existing incentive allocation approaches.


Robust Task Scheduling for Heterogeneous Robot Teams under Capability Uncertainty

arXiv.org Artificial Intelligence

This paper develops a stochastic programming framework for multi-agent systems where task decomposition, assignment, and scheduling problems are simultaneously optimized. The framework can be applied to heterogeneous mobile robot teams with distributed sub-tasks. Examples include pandemic robotic service coordination, explore and rescue, and delivery systems with heterogeneous vehicles. Due to their inherent flexibility and robustness, multi-agent systems are applied in a growing range of real-world problems that involve heterogeneous tasks and uncertain information. Most previous works assume one fixed way to decompose a task into roles that can later be assigned to the agents. This assumption is not valid for a complex task where the roles can vary and multiple decomposition structures exist. Meanwhile, it is unclear how uncertainties in task requirements and agent capabilities can be systematically quantified and optimized under a multi-agent system setting. A representation for complex tasks is proposed: agent capabilities are represented as a vector of random distributions, and task requirements are verified by a generalizable binary function. The conditional value at risk (CVaR) is chosen as a metric in the objective function to generate robust plans. An efficient algorithm is described to solve the model, and the whole framework is evaluated in two different practical test cases: capture-the-flag and robotic service coordination during a pandemic (e.g., COVID-19). Results demonstrate that the framework is generalizable, scalable up to 140 agents and 40 tasks for the example test cases, and provides low-cost plans that ensure a high probability of success.


A simple but strong baseline for online continual learning: Repeated Augmented Rehearsal

arXiv.org Artificial Intelligence

Online continual learning (OCL) aims to train neural networks incrementally from a non-stationary data stream with a single pass through data. Rehearsal-based methods attempt to approximate the observed input distributions over time with a small memory and revisit them later to avoid forgetting. Despite their strong empirical performance, rehearsal methods still suffer from a poor approximation of past data's loss landscape with memory samples. This paper revisits the rehearsal dynamics in online settings. We provide theoretical insights on the inherent memory overfitting risk from the viewpoint of biased and dynamic empirical risk minimization, and examine the merits and limits of repeated rehearsal. Inspired by our analysis, a simple and intuitive baseline, repeated augmented rehearsal (RAR), is designed to address the underfitting-overfitting dilemma of online rehearsal. Surprisingly, across four rather different OCL benchmarks, this simple baseline outperforms vanilla rehearsal by 9%-17% and also significantly improves the state-of-the-art rehearsal-based methods MIR, ASER, and SCR. We also demonstrate that RAR successfully achieves an accurate approximation of the loss landscape of past data and high-loss ridge aversion in its learning trajectory. Extensive ablation studies are conducted to study the interplay between repeated and augmented rehearsal, and reinforcement learning (RL) is applied to dynamically adjust the hyperparameters of RAR to balance the stability-plasticity trade-off online.


Transformers on Multilingual Clause-Level Morphology

arXiv.org Artificial Intelligence

This paper describes our winning systems in MRL: The 1st Shared Task on Multilingual Clause-level Morphology (EMNLP 2022 Workshop) designed by KUIS AI NLP team. We present our work for all three parts of the shared task: inflection, reinflection, and analysis. We mainly explore transformers with two approaches: (i) training models from scratch in combination with data augmentation, and (ii) transfer learning with prefix-tuning at multilingual morphological tasks. Data augmentation significantly improves performance for most languages in the inflection and reinflection tasks. On the other hand, Prefix-tuning on a pre-trained mGPT model helps us to adapt analysis tasks in low-data and multilingual settings. While transformer architectures with data augmentation achieved the most promising results for inflection and reinflection tasks, prefix-tuning on mGPT received the highest results for the analysis task. Our systems received 1st place in all three tasks in MRL 2022.


Send in the drones: how to transform Australia's fight against bushfires and floods

The Guardian

In the wake of storms of the near future, swarms of drones could replace helicopters and planes, providing emergency crews with more rapid and accurate data on the coming threats of lightning-sparked bushfires or flash floods heading for homes. Authorities now rely on satellites, which require clear weather during daytime and may only provide resolution down to 10 metres. Alternatively, pilots of aircraft may burn as much as $3,400 worth of fuel an hour and often can't fly for safety reasons. Enter firms such as Sydney-based Carbonix, a developer that started out designing America's Cup racing yachts before changing tack to make drones capable of flying eight hours or longer with resolution fine enough to read words on a piece of paper. Dario Valenza, chief technology officer and founder of Carbonix, says thermal cameras on the drones could quickly verify fires started by lightning in remote regions, helping to direct fire crews to the scene "with only a few per cent of the fuel" used by conventional aircraft that might have their operations curtailed by weather.


Australia bets on facial recognition for problem gamblers

The Japan Times

MELBOURNE – As guests arrive at eastern Australia's Warilla Hotel, a small camera equipped with facial recognition software scans their faces as part of a plan to tackle problem gambling. The tech -- which uses artificial intelligence to identify addicts who have asked to be barred from betting sites -- is set to be rolled out across gambling venues in the state of New South Wales next year. This could be due to a conflict with your ad-blocking or security software. Please add japantimes.co.jp and piano.io to your list of allowed sites. If this does not resolve the issue or you are unable to add the domains to your allowlist, please see this support page.


Artificial Intelligence Goes Vegan - Forbes India

#artificialintelligence

Artificial intelligence can be used to generate pro-vegan copy. Artificial intelligence can be used to generate pro-vegan copy. Image: Shutterstock What if, in the future, robots were the ones starting petitions to defend the rights of animals? It may sound like science fiction, yet artificial intelligence that can specifically generate vegan content has been developed in New Zealand. Will future advertising campaigns promoting meat-free alternatives or soy milk be written by artificial intelligence? The question is especially relevant because a New Zealand start-up has developed the very first AI tool capable of automatically generating content in support of veganism.


Online Anomalous Subtrajectory Detection on Road Networks with Deep Reinforcement Learning

arXiv.org Artificial Intelligence

Detecting anomalous trajectories has become an important task in many location-based applications. While many approaches have been proposed for this task, they suffer from various issues including (1) incapability of detecting anomalous subtrajectories, which are finer-grained anomalies in trajectory data, and/or (2) non-data driven, and/or (3) requirement of sufficient supervision labels which are costly to collect. In this paper, we propose a novel reinforcement learning based solution called RL4OASD, which avoids all aforementioned issues of existing approaches. RL4OASD involves two networks, one responsible for learning features of road networks and trajectories and the other responsible for detecting anomalous subtrajectories based on the learned features, and the two networks can be trained iteratively without labeled data. Extensive experiments are conducted on two real datasets, and the results show that our solution can significantly outperform the state-of-the-art methods (with 20-30% improvement) and is efficient for online detection (it takes less than 0.1ms to process each newly generated data point).