About Me

I am an Assistant Professor in Health Informatics and Information Systems at the University of Ottawa. I also hold an Adjunct Faculty position at the Faculty of Computer Science at Dalhousie University. Before that, I was a Research Associate and Post-Doctoral Fellow at the NICHE Research Group at Dalhousie University. I was a teaching assistant for 6 years at the Vrije Universiteit Brussel, obtaining the degree of Doctor in Sciences in 2013.
Research Interests
My research interests lie at the crossroads of Knowledge Representation and Reasoning (KR), Information Systems (IS) engineering, and Mobile Computing. In particular, I am interested in applying these technologies to innovate domains such as healthcare, law, government and business.
Publications
2022
William Van Woensel; Samina Abidi; Karthik Tennankore; George Worthen; Syed Sibte Raza Abidi
Clinical Guidelines as Executable and Interactive Workflows with FHIR-Compliant Health Data Input using GLEAN Proceedings Article
In: 20th International Conference on Artificial Intelligence in Medicine (AIME 2022): Demo Track, June 14-17, Halifax, 2022, Springer, 2022.
BibTeX | Tags: Clinical Decision Support Systems, Clinical guidelines, Notation3, Semantic Web reasoning, Task Network Models
@inproceedings{glean-demo,
title = {Clinical Guidelines as Executable and Interactive Workflows with FHIR-Compliant Health Data Input using GLEAN},
author = {William Van Woensel and Samina Abidi and Karthik Tennankore and George Worthen and Syed Sibte Raza Abidi},
year = {2022},
date = {2022-06-17},
urldate = {2022-06-17},
booktitle = {20th International Conference on Artificial Intelligence in Medicine (AIME 2022): Demo Track, June 14-17, Halifax, 2022},
publisher = {Springer},
keywords = {Clinical Decision Support Systems, Clinical guidelines, Notation3, Semantic Web reasoning, Task Network Models},
pubstate = {published},
tppubtype = {inproceedings}
}
William Van Woensel; Samina Abidi; Karthik Tennankore; George Worthen; Syed Sibte Raza Abidi
Explainable Decision Support using Task Network Models in Notation3: Computerizing Lipid Management Clinical Guidelines as Interactive Task Networks Proceedings Article
In: 20th International Conference on Artificial Intelligence in Medicine (AIME 2022), June 14-17, 2022, Halifax, Springer, 2022.
BibTeX | Tags: Clinical Decision Support Systems, Clinical guidelines, Notation3, Semantic Web reasoning, Task Network Models
@inproceedings{glean_2022,
title = {Explainable Decision Support using Task Network Models in Notation3: Computerizing Lipid Management Clinical Guidelines as Interactive Task Networks},
author = {William Van Woensel and Samina Abidi and Karthik Tennankore and George Worthen and Syed Sibte Raza Abidi},
year = {2022},
date = {2022-06-17},
urldate = {2022-06-17},
booktitle = {20th International Conference on Artificial Intelligence in Medicine (AIME 2022), June 14-17, 2022, Halifax},
publisher = {Springer},
keywords = {Clinical Decision Support Systems, Clinical guidelines, Notation3, Semantic Web reasoning, Task Network Models},
pubstate = {published},
tppubtype = {inproceedings}
}
William Van Woensel; Floriano Scioscia; Giuseppe Loseto; Oshani Seneviratne; Evan Patton; Samina Abidi; Lalana Kagal
Explainable Clinical Decision Support: Towards Patient-Facing Explanations for Education and Long-term Behavior Change Proceedings Article
In: 20th International Conference on Artificial Intelligence in Medicine (AIME 2022): Demo Track, June 14-17, Halifax, 2022, Springer, 2022.
BibTeX | Tags: Explainability, Semantic Web reasoning
@inproceedings{explain_2022,
title = {Explainable Clinical Decision Support: Towards Patient-Facing Explanations for Education and Long-term Behavior Change},
author = {William Van Woensel and Floriano Scioscia and Giuseppe Loseto and Oshani Seneviratne and Evan Patton and Samina Abidi and Lalana Kagal},
year = {2022},
date = {2022-06-17},
urldate = {2022-06-17},
booktitle = {20th International Conference on Artificial Intelligence in Medicine (AIME 2022): Demo Track, June 14-17, Halifax, 2022},
publisher = {Springer},
keywords = {Explainability, Semantic Web reasoning},
pubstate = {published},
tppubtype = {inproceedings}
}
2018
William Van Woensel; Syed Sibte Raza Abidi
Benchmarking Semantic Reasoning on Mobile Platforms: Towards Optimization Using OWL2 RL Journal Article
In: Semantic Web Journal, 2018.
Abstract | Links | BibTeX | Tags: Mobile Computing, OWL2 RL, Semantic Web reasoning
@article{SWJ-WVW-2018,
title = {Benchmarking Semantic Reasoning on Mobile Platforms: Towards Optimization Using OWL2 RL},
author = {William Van Woensel and Syed Sibte Raza Abidi},
url = {http://www.semantic-web-journal.net/system/files/swj1881.pdf},
year = {2018},
date = {2018-08-06},
journal = {Semantic Web Journal},
abstract = {Mobile hardware has advanced to a point where apps may consume the Semantic Web of Data, as exemplified in domains such as mobile context-awareness, m-Health, m-Tourism and augmented reality. However, recent work shows that the performance of ontology-based reasoning, an essential Semantic Web building block, still leaves much to be desired on mobile platforms. This presents a clear need to provide developers with the ability to benchmark mobile reasoning performance, based on their particular application scenarios, i.e., including reasoning tasks, process flows and datasets, to establish the feasibility of mobile deployment. In this regard, we present a mobile benchmark framework called MobiBench to help developers to benchmark semantic reasoners on mobile platforms. To realize efficient mobile, ontology-based reasoning, OWL2 RL is a promising solution since it (a) trades expressivity for scalability, which is important on resource-constrained platforms; and (b) provides unique opportunities for optimization due to its rule-based axiomatization. In this vein, we propose selections of OWL2 RL rule subsets for optimization purposes, based on several orthogonal dimensions. We extended MobiBench to support OWL2 RL and the proposed ruleset selections, and benchmarked multiple OWL2 RL-enabled rule engines and OWL reasoners on a mobile platform. Our results show significant performance improvements by applying OWL2 RL rule subsets, allowing performant reasoning for small datasets on mobile systems.},
keywords = {Mobile Computing, OWL2 RL, Semantic Web reasoning},
pubstate = {published},
tppubtype = {article}
}
Hossein Mohammadhassanzadeh; Samina Abidi; William Van Woensel; Syed Sibte Raza Abidi
Investigating Plausible Reasoning over Knowledge Graphs for Semantics-based Health Data Analytics Proceedings Article
In: Data Exploration in the Web 3.0 Age (DEW) conference track at 27th IEEE International Conference on Enabling Technologies: Infrastructure for Collaborative Enterprises (WETICE’18), IEEE, Paris, France, 2018.
Links | BibTeX | Tags: Plausible reasoning, Query Rewriting, Semantic Analytics, Semantic Web reasoning
@inproceedings{Mohammadhassanzadeh;2018,
title = {Investigating Plausible Reasoning over Knowledge Graphs for Semantics-based Health Data Analytics},
author = {Hossein Mohammadhassanzadeh and Samina Abidi and William Van Woensel and Syed Sibte Raza Abidi},
url = {https://ieeexplore.ieee.org/document/8495925},
year = {2018},
date = {2018-06-27},
booktitle = {Data Exploration in the Web 3.0 Age (DEW) conference track at 27th IEEE International Conference on Enabling Technologies: Infrastructure for Collaborative Enterprises (WETICE’18)},
publisher = {IEEE},
address = {Paris, France},
keywords = {Plausible reasoning, Query Rewriting, Semantic Analytics, Semantic Web reasoning},
pubstate = {published},
tppubtype = {inproceedings}
}
William Van Woensel; Syed Sibte Raza Abidi
Optimizing Semantic Reasoning on Memory-Constrained Platforms using the RETE Algorithm Proceedings Article
In: 15th Extended Semantic Web Conference (ESWC 2018), pp. 682-696, Springer LNCS, Heraklion, Greece, 2018.
Abstract | Links | BibTeX | Tags: Mobile Computing, OWL2 RL, RETE, Semantic Web reasoning
@inproceedings{ESWC-WVW-2018,
title = {Optimizing Semantic Reasoning on Memory-Constrained Platforms using the RETE Algorithm},
author = {William Van Woensel and Syed Sibte Raza Abidi},
doi = {10.1007/978-3-319-93417-4_44},
year = {2018},
date = {2018-06-07},
booktitle = {15th Extended Semantic Web Conference (ESWC 2018)},
pages = {682-696},
publisher = {Springer LNCS},
address = {Heraklion, Greece},
abstract = {Mobile hardware improvements have opened the door for deploying rule systems on ubiquitous, mobile platforms. By executing rule-based tasks locally, less re-mote (cloud) resources are needed, bandwidth usage is reduced, and local, time-sensitive tasks are no longer influenced by network conditions. Further, with data being increasingly published in semantic format, an opportunity arises for rule systems to leverage the embedded semantics of semantic, ontology-based data. To support this kind of ontology-based reasoning in rule systems, rule-based axiomatizations of ontology semantics can be utilized (e.g., OWL 2 RL). Nonetheless, recent benchmarks have found that any kind of ontology-based reasoning on mobile platforms still lacks scalability, at least when directly re-using existing (PC- or server-based) technologies. To create a tailored solution for resource-constrained platforms, we propose changes to RETE, the mainstay algorithm for production rule systems. In particular, we present an adapted algorithm that, by selectively pooling RETE memories, aims to better balance memory usage with performance. Further, we show that this algorithm is well-suited towards many typical Semantic Web scenarios. Using our custom algorithm, we perform an extensive evaluation of semantic reasoning both on the PC and mobile platform.},
keywords = {Mobile Computing, OWL2 RL, RETE, Semantic Web reasoning},
pubstate = {published},
tppubtype = {inproceedings}
}
2017
William Van Woensel; Patrice C. Roy; Syed Sibte Raza Abidi
Achieving Pro-Active Guidance of Patients through ADL via Knowledge-Driven Activity Recognition and Complex Semantic Workflows Proceedings Article
In: 10th International Conference on Semantic Web Applications and Tools for Life Sciences, CEUR, Rome, Italy, 2017.
Links | BibTeX | Tags: Activity Recognition, Ambient Intelligence, Semantic Web reasoning
@inproceedings{ADL201,
title = {Achieving Pro-Active Guidance of Patients through ADL via Knowledge-Driven Activity Recognition and Complex Semantic Workflows},
author = {William Van Woensel and Patrice C. Roy and Syed Sibte Raza Abidi},
url = {https://niche.cs.dal.ca/wp-content/uploads/2017/12/paper_camera-ready.pdf},
year = {2017},
date = {2017-12-06},
booktitle = {10th International Conference on Semantic Web Applications and Tools for Life Sciences},
publisher = {CEUR},
address = {Rome, Italy},
keywords = {Activity Recognition, Ambient Intelligence, Semantic Web reasoning},
pubstate = {published},
tppubtype = {inproceedings}
}
Hossein Mohammadhassanzadeh; William Van Woensel; Samina Raza Abidi; Syed Sibte Raza Abidi
Semantics-based Plausible Reasoning to Extend the Knowledge Coverage of Medical Knowledge Bases for Improved Clinical Decision Support Journal Article
In: Journal of BioData Mining, vol. 10, no. 7, 2017.
Abstract | Links | BibTeX | Tags: Analogical reasoning, Inductive generalization, Medical knowledge bases, Plausible reasoning, Semantic Web reasoning
@article{Mohammadhassanzadeh2017,
title = {Semantics-based Plausible Reasoning to Extend the Knowledge Coverage of Medical Knowledge Bases for Improved Clinical Decision Support},
author = {Hossein Mohammadhassanzadeh and William Van Woensel and Samina Raza Abidi and Syed Sibte Raza Abidi},
url = {http://rdcu.be/paPY},
doi = {10.1186/s13040-017-0123-y},
year = {2017},
date = {2017-02-10},
journal = {Journal of BioData Mining},
volume = {10},
number = {7},
abstract = {Background
Capturing complete medical knowledge is challenging-often due to incomplete patient Electronic Health Records (EHR), but also because of valuable, tacit medical knowledge hidden away in physicians’ experiences. To extend the coverage of incomplete medical knowledge-based systems beyond their deductive closure, and thus enhance their decision-support capabilities, we argue that innovative, multi-strategy reasoning approaches should be applied. In particular, plausible reasoning mechanisms apply patterns from human thought processes, such as generalization, similarity and interpolation, based on attributional, hierarchical, and relational knowledge. Plausible reasoning mechanisms include inductive reasoning, which generalizes the commonalities among the data to induce new rules, and analogical reasoning, which is guided by data similarities to infer new facts. By further leveraging rich, biomedical Semantic Web ontologies to represent medical knowledge, both known and tentative, we increase the accuracy and expressivity of plausible reasoning, and cope with issues such as data heterogeneity, inconsistency and interoperability. In this paper, we present a Semantic Web-based, multi-strategy reasoning approach, which integrates deductive and plausible reasoning and exploits Semantic Web technology to solve complex clinical decision support queries.
Results
We evaluated our system using a real-world medical dataset of patients with hepatitis, from which we randomly removed different percentages of data (5%, 10%, 15%, and 20%) to reflect scenarios with increasing amounts of incomplete medical knowledge. To increase the reliability of the results, we generated 5 independent datasets for each percentage of missing values, which resulted in 20 experimental datasets (in addition to the original dataset). The results show that plausibly inferred knowledge extends the coverage of the knowledge base by, on average, 2%, 7%, 12%, and 16% for datasets with, respectively, 5%, 10%, 15%, and 20% of missing values. This expansion in the KB coverage allowed solving complex disease diagnostic queries that were previously unresolvable, without losing the correctness of the answers. However, compared to deductive reasoning, data-intensive plausible reasoning mechanisms yield a significant performance overhead.
Conclusions
We observed that plausible reasoning approaches, by generating tentative inferences and leveraging domain knowledge of experts, allow us to extend the coverage of medical knowledge bases, resulting in improved clinical decision support. Second, by leveraging OWL ontological knowledge, we are able to increase the expressivity and accuracy of plausible reasoning methods. Third, our approach is applicable to clinical decision support systems for a range of chronic diseases.},
keywords = {Analogical reasoning, Inductive generalization, Medical knowledge bases, Plausible reasoning, Semantic Web reasoning},
pubstate = {published},
tppubtype = {article}
}
Capturing complete medical knowledge is challenging-often due to incomplete patient Electronic Health Records (EHR), but also because of valuable, tacit medical knowledge hidden away in physicians’ experiences. To extend the coverage of incomplete medical knowledge-based systems beyond their deductive closure, and thus enhance their decision-support capabilities, we argue that innovative, multi-strategy reasoning approaches should be applied. In particular, plausible reasoning mechanisms apply patterns from human thought processes, such as generalization, similarity and interpolation, based on attributional, hierarchical, and relational knowledge. Plausible reasoning mechanisms include inductive reasoning, which generalizes the commonalities among the data to induce new rules, and analogical reasoning, which is guided by data similarities to infer new facts. By further leveraging rich, biomedical Semantic Web ontologies to represent medical knowledge, both known and tentative, we increase the accuracy and expressivity of plausible reasoning, and cope with issues such as data heterogeneity, inconsistency and interoperability. In this paper, we present a Semantic Web-based, multi-strategy reasoning approach, which integrates deductive and plausible reasoning and exploits Semantic Web technology to solve complex clinical decision support queries.
Results
We evaluated our system using a real-world medical dataset of patients with hepatitis, from which we randomly removed different percentages of data (5%, 10%, 15%, and 20%) to reflect scenarios with increasing amounts of incomplete medical knowledge. To increase the reliability of the results, we generated 5 independent datasets for each percentage of missing values, which resulted in 20 experimental datasets (in addition to the original dataset). The results show that plausibly inferred knowledge extends the coverage of the knowledge base by, on average, 2%, 7%, 12%, and 16% for datasets with, respectively, 5%, 10%, 15%, and 20% of missing values. This expansion in the KB coverage allowed solving complex disease diagnostic queries that were previously unresolvable, without losing the correctness of the answers. However, compared to deductive reasoning, data-intensive plausible reasoning mechanisms yield a significant performance overhead.
Conclusions
We observed that plausible reasoning approaches, by generating tentative inferences and leveraging domain knowledge of experts, allow us to extend the coverage of medical knowledge bases, resulting in improved clinical decision support. Second, by leveraging OWL ontological knowledge, we are able to increase the expressivity and accuracy of plausible reasoning methods. Third, our approach is applicable to clinical decision support systems for a range of chronic diseases.