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20212026
most citedConvolutional Neural Network Models and Interpretability for the Anisotropic Reynolds Stress Tensor in Turbulent One-dimensional Flows

3 citations · 7 across the 22 of their papers we have counts for

collaborators

23 papers

physics.flu-dyn2026

Airfoil2Vec: Spectral Geometry-Conditioned Neural Surrogate Models for Airfoil Aerodynamics and a Downforce-Generating CFD Dataset

Haitz Sáez de Ocáriz Borde, Flavio Savarino, Andrei Cristian Popescu +3

We introduce a dataset of approximately 10,000 Reynolds-Averaged Navier-Stokes (RANS) simulations of steady, incompressible, two-dimensional subsonic flow around downforce-generati…

cs.LG2026

Algorithmic Foundations of Deep Learning: Complexity-Theoretic Rates and a Characterization of Universal Approximation

Anastasis Kratsios, Simone Brugiapaglia, Bum Jun Kim +2

Feedforward neural network (NN) expressivity is typically studied by emulating optimal basis-expansion schemes. While powerful, this perspective is incomplete: it primarily capture…

stat.ML2026

Every Feedforward Neural Network Definable in an o-Minimal Structure Has Finite Sample Complexity

Anastasis Kratsios, Gregory Cousins, Haitz Sáez de Ocáriz Borde +2

We show that, in a precise sense, a broad class of feedforward neural networks learn (have finite sample complexity) in the PAC model: every fixed finite feedforward architecture w…

cs.LG2026

k-Maximum Inner Product Attention for Graph Transformers and the Expressive Power of GraphGPS

Jonas De Schouwer, Haitz Sáez de Ocáriz Borde, Xiaowen Dong

Graph transformers have shown promise in overcoming limitations of traditional graph neural networks, such as oversquashing and difficulties in modeling long-range dependencies. Ho…

cs.LG2025

Assessing the Geographic Generalization and Physical Consistency of Generative Models for Climate Downscaling

Carlo Saccardi, Maximilian Pierzyna, Haitz Sáez de Ocáriz Borde +6

Kilometer-scale weather data is crucial for real-world applications but remains computationally intensive to produce using traditional weather simulations. An emerging solution is…

cs.LG2025

Bridging Graph and State-Space Modeling for Intensive Care Unit Length of Stay Prediction

Shuqi Zi, Haitz Sáez de Ocáriz Borde, Emma Rocheteau +1

Predicting a patient's length of stay (LOS) in the intensive care unit (ICU) is a critical task for hospital resource management, yet remains challenging due to the heterogeneous a…

cs.LG2025

Mathematical Foundations of Geometric Deep Learning

Haitz Sáez de Ocáriz Borde, Michael Bronstein

We review the key mathematical concepts necessary for studying Geometric Deep Learning.

cs.CV2025

Structured Captions Improve Prompt Adherence in Text-to-Image Models (Re-LAION-Caption 19M)

Nicholas Merchant, Haitz Sáez de Ocáriz Borde, Andrei Cristian Popescu +1

We argue that generative text-to-image models often struggle with prompt adherence due to the noisy and unstructured nature of large-scale datasets like LAION-5B. This forces users…

cs.LG2025

LoRA Fine-Tuning Without GPUs: A CPU-Efficient Meta-Generation Framework for LLMs

Reza Arabpour, Haitz Sáez de Ocáriz Borde, Anastasis Kratsios

Low-Rank Adapters (LoRAs) have transformed the fine-tuning of Large Language Models (LLMs) by enabling parameter-efficient updates. However, their widespread adoption remains limit…

cs.LG2025

Beyond Parallelism: Synergistic Computational Graph Effects in Multi-Head Attention

Haitz Sáez de Ocáriz Borde

Multi-head attention powers Transformer networks, the primary deep learning architecture behind the success of large language models (LLMs). Yet, the theoretical advantages of mult…

cs.CV2025

Fine-Tuning Next-Scale Visual Autoregressive Models with Group Relative Policy Optimization

Matteo Gallici, Haitz Sáez de Ocáriz Borde

Fine-tuning pre-trained generative models with Reinforcement Learning (RL) has emerged as an effective approach for aligning outputs more closely with nuanced human preferences. In…

cs.LG2025

Towards Quantifying Long-Range Interactions in Graph Machine Learning: a Large Graph Dataset and a Measurement

Huidong Liang, Haitz Sáez de Ocáriz Borde, Baskaran Sripathmanathan +2

Long-range dependencies are critical for effective graph representation learning, yet most existing datasets focus on small graphs tailored to inductive tasks, offering limited ins…

cs.CV2025

Keep It Light! Simplifying Image Clustering Via Text-Free Adapters

Yicen Li, Haitz Sáez de Ocáriz Borde, Anastasis Kratsios +1

In the era of pre-trained models, effective classification can often be achieved using simple linear probing or lightweight readout layers. In contrast, many competitive clustering…

cs.LG2024

Scalable Message Passing Neural Networks: No Need for Attention in Large Graph Representation Learning

Haitz Sáez de Ocáriz Borde, Artem Lukoianov, Anastasis Kratsios +2

We propose Scalable Message Passing Neural Networks (SMPNNs) and demonstrate that, by integrating standard convolutional message passing into a Pre-Layer Normalization Transformer-…

cs.LG2024★ 2 cited

Neural Spacetimes for DAG Representation Learning

Haitz Sáez de Ocáriz Borde, Anastasis Kratsios, Marc T. Law +2

We propose a class of trainable deep learning-based geometries called Neural Spacetimes (NSTs), which can universally represent nodes in weighted directed acyclic graphs (DAGs) as…

cs.CV2024★ 1 cited

Score Distillation via Reparametrized DDIM

Artem Lukoianov, Haitz Sáez de Ocáriz Borde, Kristjan Greenewald +4

While 2D diffusion models generate realistic, high-detail images, 3D shape generation methods like Score Distillation Sampling (SDS) built on these 2D diffusion models produce cart…

cs.LG2024

Asymmetry in Low-Rank Adapters of Foundation Models

Jiacheng Zhu, Kristjan Greenewald, Kimia Nadjahi +6

Parameter-efficient fine-tuning optimizes large, pre-trained foundation models by updating a subset of parameters; in this class, Low-Rank Adaptation (LoRA) is particularly effecti…

stat.ML2024

Approximation Rates and VC-Dimension Bounds for (P)ReLU MLP Mixture of Experts

Anastasis Kratsios, Haitz Sáez de Ocáriz Borde, Takashi Furuya +1

Mixture-of-Experts (MoEs) can scale up beyond traditional deep learning models by employing a routing strategy in which each input is processed by a single "expert" deep learning m…

cs.LG2023

AMES: A Differentiable Embedding Space Selection Framework for Latent Graph Inference

Yuan Lu, Haitz Sáez de Ocáriz Borde, Pietro Liò

In real-world scenarios, although data entities may possess inherent relationships, the specific graph illustrating their connections might not be directly accessible. Latent graph…

cs.LG2023★ 1 cited

Neural Snowflakes: Universal Latent Graph Inference via Trainable Latent Geometries

Haitz Sáez de Ocáriz Borde, Anastasis Kratsios

The inductive bias of a graph neural network (GNN) is largely encoded in its specified graph. Latent graph inference relies on latent geometric representations to dynamically rewir…

cs.LG2023

Capacity Bounds for Hyperbolic Neural Network Representations of Latent Tree Structures

Anastasis Kratsios, Ruiyang Hong, Haitz Sáez de Ocáriz Borde

We study the representation capacity of deep hyperbolic neural networks (HNNs) with a ReLU activation function. We establish the first proof that HNNs can -isometrical…

physics.flu-dyn2021

Multi-Task Learning based Convolutional Models with Curriculum Learning for the Anisotropic Reynolds Stress Tensor in Turbulent Duct Flow

Haitz Sáez de Ocáriz Borde, David Sondak, Pavlos Protopapas

The Reynolds-averaged Navier-Stokes (RANS) equations require accurate modeling of the anisotropic Reynolds stress tensor. Traditional closure models, while sophisticated, often onl…

physics.flu-dyn2021★ 3 cited

Convolutional Neural Network Models and Interpretability for the Anisotropic Reynolds Stress Tensor in Turbulent One-dimensional Flows

Haitz Sáez de Ocáriz Borde, David Sondak, Pavlos Protopapas

The Reynolds-averaged Navier-Stokes (RANS) equations are widely used in turbulence applications. They require accurately modeling the anisotropic Reynolds stress tensor, for which…