MS Thesis Defense: Description Logic EL++Embeddings with Intersectional Closure by Xi Peng

Xi Peng MS Student under the supervision of Professor Robert Hoehndorf successfully defended his thesis "Description Logic EL++Embeddings with Intersectional Closure"

Abstract:
Many ontologies, in particular in the biomedical domain, are based on the Description Logic EL++. Several efforts have been made to interpret and exploit EL++ontologies by distributed representation learning. Specifically, concepts within EL++theories have been represented as n-balls within an n-dimensional embedding space. However, the intersec- tional closure is not satisfied when using n-balls to represent concepts because the intersec- tion of two n-balls is not an n-ball. This leads to challenges when measuring the distance between concepts and inferring equivalence between concepts. To this end, I developed EL Box Embedding (ELBE) to learn Description Logic EL++embeddings using axis-parallel boxes. I generate specially designed box-based geometric constraints from EL++axioms for model training. Since the intersection of boxes remains as a box, the intersectional closure is satisfied. I report extensive experimental results on three datasets and present a case study to demonstrate the effectiveness of the proposed method.Many ontologies, in particular in the biomedical domain, are based on the Description Logic EL++. Several efforts have been made to interpret and exploit EL++ontologies by distributed representa- tion learning. Specifically, concepts within EL++theories have been represented as n-balls within an n-dimensional embedding space. However, the intersectional closure is not sat- isfied when using n-balls to represent concepts because the intersection of two n-balls is not an n-ball. This leads to challenges when measuring the distance between concepts and inferring equivalence between concepts. To this end, I developed EL Box Embedding (ELBE) to learn Description Logic EL++embeddings using axis-parallel boxes. I generate specially designed box-based geometric constraints from EL++axioms for model training. Since the intersection of boxes remains as a box, the intersectional closure is satisfied. I report extensive experimental results on three datasets and present a case study to demon- strate the effectiveness of the proposed method.

Bio: 
Xi Peng received his BSc degree in Computer Science from the SUSTech China, in 2021.  Soon after, he was admitted at KAUST for M.S. in Computer Science and joined the Computational Bioscience Research Center (CBRC) to conduct his master’s thesis.  Currently, his research on description logic el++ embeddings is supervised by Prof. Robert Hoehndorf.