We present a knowledge integration framework (called KIF) that uses Wikidata as a lingua franca to integrate heterogeneous knowledge bases. These can be triplestores, relational databases, CSV files, etc., which may or may not use the Wikidata dialect of RDF. KIF leverages Wikidata's data model and vocabulary plus user-defined mappings to expose a unified view of the integrated bases while keeping track of the context and provenance of their statements. The result is a virtual knowledge base which behaves like an "extended Wikidata" and which can be queried either through an efficient filter interface or using SPARQL. We present the design and implementation of KIF, discuss how we have used it to solve a real integration problem in the domain of chemistry (involving Wikidata, PubChem, and IBM CIRCA), and present experimental results on the performance and overhead of KIF.

Machine Learning (ML) has been fundamentally transforming several industries and businesses in numerous ways. More recently, it has also been impacting computational science and engineering domains, such as geoscience, climate science, material science, and health science. Scientific ML, i.e., ML applied to these domains, is characterized by the combination of data-driven techniques with domain-specific data and knowledge to obtain models of physical phenomena [1], [2], [3], [4], [5]. Obtaining models in scientific ML works similarly to conducting traditional large-scale computational experiments [6], which involve a team of scientists and engineers that formulate hypotheses, design the experiment and predefine parameters and input datasets, analyze the experiment data, do observations, and calibrate initial assumptions in a cycle until they are satisfied with the results. Scientific ML is naturally large-scale because multiple people collaborate in a project, using their multidisciplinary domain-specific knowledge to design and perform data-intensive tasks to curate (i.e., understand, clean, enrich with observations) datasets and prepare for learning algorithms. They then plan and execute compute-intensive tasks for computational simulations or training ML models affected by the scientific domain's constraints. They utilize specialized scientific software tools running either on their desktops, on cloud clusters (e.g., Docker-based), or large HPC machines.