Goto

Collaborating Authors

 South America


Physics-Aware Neural Networks for Boundary Layer Linear Problems

arXiv.org Artificial Intelligence

Physics-Informed Neural Networks (PINNs) are machine learning tools that approximate the solution of general partial differential equations (PDEs) by adding them in some form as terms of the loss/cost function of a Neural Network. Most pieces of work in the area of PINNs tackle non-linear PDEs. Nevertheless, many interesting problems involving linear PDEs may benefit from PINNs; these include parametric studies, multi-query problems, and parabolic (transient) PDEs. The purpose of this paper is to explore PINNs for linear PDEs whose solutions may present one or more boundary layers. More specifically, we analyze the steady-state reaction-advection-diffusion equation in regimes in which the diffusive coefficient is small in comparison with the reactive or advective coefficients. We show that adding information about these coefficients as predictor variables in a PINN results in better prediction models than in a PINN that only uses spatial information as predictor variables. This finding may be instrumental in multiscale problems where the coefficients of the PDEs present high variability in small spatiotemporal regions of the domain, and therefore PINNs may be employed together with domain decomposition techniques to efficiently approximate the PDEs locally at each partition of the spatiotemporal domain, without resorting to different learned PINN models at each of these partitions.


Domain Adaptation for Time-Series Classification to Mitigate Covariate Shift

arXiv.org Artificial Intelligence

The performance of a machine learning model degrades when it is applied to data from a similar but different domain than the data it has initially been trained on. To mitigate this domain shift problem, domain adaptation (DA) techniques search for an optimal transformation that converts the (current) input data from a source domain to a target domain to learn a domain-invariant representation that reduces domain discrepancy. This paper proposes a novel supervised DA based on two steps. First, we search for an optimal class-dependent transformation from the source to the target domain from a few samples. We consider optimal transport methods such as the earth mover's distance, Sinkhorn transport and correlation alignment. Second, we use embedding similarity techniques to select the corresponding transformation at inference. We use correlation metrics and higher-order moment matching techniques. We conduct an extensive evaluation on time-series datasets with domain shift including simulated and various online handwriting datasets to demonstrate the performance.


Sequence-aware multimodal page classification of Brazilian legal documents

arXiv.org Artificial Intelligence

The Brazilian Supreme Court receives tens of thousands of cases each semester. Court employees spend thousands of hours to execute the initial analysis and classification of those cases -- which takes effort away from posterior, more complex stages of the case management workflow. In this paper, we explore multimodal classification of documents from Brazil's Supreme Court. We train and evaluate our methods on a novel multimodal dataset of 6,510 lawsuits (339,478 pages) with manual annotation assigning each page to one of six classes. Each lawsuit is an ordered sequence of pages, which are stored both as an image and as a corresponding text extracted through optical character recognition. We first train two unimodal classifiers: a ResNet pre-trained on ImageNet is fine-tuned on the images, and a convolutional network with filters of multiple kernel sizes is trained from scratch on document texts. We use them as extractors of visual and textual features, which are then combined through our proposed Fusion Module. Our Fusion Module can handle missing textual or visual input by using learned embeddings for missing data. Moreover, we experiment with bi-directional Long Short-Term Memory (biLSTM) networks and linear-chain conditional random fields to model the sequential nature of the pages. The multimodal approaches outperform both textual and visual classifiers, especially when leveraging the sequential nature of the pages.


Local Approximations, Real Interpolation and Machine Learning

arXiv.org Artificial Intelligence

We suggest a novel classification algorithm that is based on local approximations and explain its connections with Artificial Neural Networks (ANNs) and Nearest Neighbour classifiers. We illustrate it on the datasets MNIST and EMNIST of images of handwritten digits. We use the dataset MNIST to find parameters of our algorithm and apply it with these parameters to the challenging EMNIST dataset. It is demonstrated that the algorithm misclassifies 0.42% of the images of EMNIST and therefore significantly outperforms predictions by humans and shallow artificial neural networks (ANNs with few hidden layers) that both have more than 1.3% of errors


Fine-Grained Population Mobility Data-Based Community-Level COVID-19 Prediction Model

arXiv.org Artificial Intelligence

Predicting the number of infections in the anti-epidemic process is extremely beneficial to the government in developing anti-epidemic strategies, especially in fine-grained geographic units. Previous works focus on low spatial resolution prediction, e.g., county-level, and preprocess data to the same geographic level, which loses some useful information. In this paper, we propose a fine-grained population mobility data-based model (FGC-COVID) utilizing data of two geographic levels for community-level COVID-19 prediction. We use the population mobility data between Census Block Groups (CBGs), which is a finer-grained geographic level than community, to build the graph and capture the dependencies between CBGs using graph neural networks (GNNs). To mine as finer-grained patterns as possible for prediction, a spatial weighted aggregation module is introduced to aggregate the embeddings of CBGs to community level based on their geographic affiliation and spatial autocorrelation. Extensive experiments on 300 days LA city COVID-19 data indicate our model outperforms existing forecasting models on community-level COVID-19 prediction.


7 Things You Need to Know About Marketing Using Artificial Intelligence

#artificialintelligence

Artificial Intelligence (AI) is not a new concept. The term was coined in 1956 by John McCarthy and Marvin Minsky, who defined it as "the science and engineering of making intelligent machines." Since then, AI has made tremendous advances, and we're still seeing even more growth today. Fortune Business Insights projects the global AI market will grow from $387 billion in 2022 to $1.4 billion by 2029. The movie iRobot was set in 2035 and told the story of a future where highly intelligent robots fill public service positions. Unfortunately, the robots in this movie turned out to be a more significant threat to humanity than expected.


Artificial Intelligence (AI) in Insurance Market May See a Big Move : Google, Microsoft , IBM: Long Term Growth Story

#artificialintelligence

New Jersey, NJ---- 07/14/2022-- The Global Artificial Intelligence in Insurance Market Report assesses developments relevant to the insurance industry and identifies key risks and vulnerabilities for the Artificial Intelligence in Insurance Industry to make stakeholders aware with current and future scenarios. To derive complete assessment and market...


No Language Left Behind

#artificialintelligence

Originally published on Towards AI the World's Leading AI and Technology News and Media Company. If you are building an AI-related product or service, we invite you to consider becoming an AI sponsor. At Towards AI, we help scale AI and technology startups. Let us help you unleash your technology to the masses. The limits of my language mean the limits of my world.


MeetKai launches AI-powered metaverse, beginning with a billboard in Occasions Sq. - Channel969

#artificialintelligence

Be a part of gaming executives to debate rising components of the business this October at GamesBeat Summit Subsequent. MeetKai is a conversational AI firm that has expanded into constructing a real-world metaverse, beginning with a billboard in Occasions Sq.. MeetKai is accessible by way of digital actuality in addition to any sensible system, and its model of the metaverse is akin to Pokémon Go creator Niantic's view, because it blends the actual world with the digital. MeetKai is the brainchild of CEO James Kaplan and billionaire Weili Dai, government chair. They spent their early years at MeetKai constructing foundational AI know-how, and now they're marrying it with the metaverse. They traveled to New York this week to unveil the MeetKai metaverse, which you'll entry in your telephone by way of a QR code on a billboard in Occasions Sq..


Have we been Naive to Select Machine Learning Models? Noisy Data are here to Stay!

arXiv.org Artificial Intelligence

The model selection procedure is usually a single-criterion decision making in which we select the model that maximizes a specific metric in a specific set, such as the Validation set performance. We claim this is very naive and can perform poor selections of over-fitted models due to the over-searching phenomenon, which over-estimates the performance on that specific set. Futhermore, real world data contains noise that should not be ignored by the model selection procedure and must be taken into account when performing model selection. Also, we have defined four theoretical optimality conditions that we can pursue to better select the models and analyze them by using a multi-criteria decision-making algorithm (TOPSIS) that considers proxies to the optimality conditions to select reasonable models.