Wendy Maccaull

• St. Francis Xavier University

The volume and diversity of healthcare data available using modern technology offers great potential for improving health services delivery. Giving clinicians and health system administrators the ability to easily investigate and analyze data from various perspectives can promote evidence-based decision-making. Current analysis approaches often res...

The volume and diversity of healthcare data available using modern technology offers great potential for improving health services delivery. Giving clinicians and health system administrators the ability to easily investigate and analyze data from various perspectives can promote evidence-based decision-making. Current analysis approaches often res...

The volume and diversity of healthcare information available through the use of modern technology offers great potential for improving health services delivery. Giving healthcare practitioners and health system administrators the ability to investigate and analyse data from various perspectives can promote evidence-based decision making. Current an...

Modern smart systems such as those needed for Industry 4.0 integrate data from various sources and increasingly require that data be contextualized with domain knowledge. The integration and contextualization of data allows for the advanced reasoning needed to generate knowledge grounded in the data under consideration. In this paper, we propose an...

Process mining is a powerful technique which uses an organization’s event data to extract and analyse process flow information and develop useful process models. However, it is difficult to apply process mining techniques to healthcare information due to factors relating to the complexity inherent in the healthcare domain and associated information...

Diagrammatic modelling is the foundation of many popular knowledge representation and software development techniques. In Model Driven Software Engineering, domain specific modelling languages are represented as metamodels and domain specific specifications are represented as models. The (meta-)models are represented by graphs and (models) instance...

We present the architecture for a framework for semantic web-based service discovery, suitable for integration with relational data-base systems. Existing discovery algorithms often lead to poor results due to limitations of the service description used and lack of domain data. Our framework incorporates context aware service discovery vis a vis dy...

Recently our research group introduced the notion of Service Enabled Workflow (SEW) with the integration of Semantic Web Service and Workflow. SEW considers workflow as a collection of tasks with specific control flow where tasks are carried out as services. In this paper, we present a Service Oriented Architecture (SOA)-based integrated applicatio...

Since a Clinical Practice Guideline describes the diagnosis and treatment process of a disease, designers of such guidelines should ensure their logical consistency. A formal approach for modeling them provides a basis for some useful reasoning (e.g., satisfiability checking). In this paper, we describe a metric interval-based temporal description...

As the world enters the age of "big data", new ways to represent and reason on enormous amounts of data are demanded and expected. Work in developing ontologies and reasoning approaches have taken steps towards addressing these needs. However, ontology development is not usually perceived as an engineering activity. Developers often overlook fundam...

Over the last decade, the world has entered into the age of “big data” and new ways to represent and reason on enormous amounts of data are required. Work in developing ontologies and sophisticated reasoning approaches partly addresses these needs. However, ontology development is currently more of an art than an engineering activity. Fundamental q...

The increasing use of Ontologies, formulated using expressive Description Logics, for time sensitive applications necessitates the development of fast (near realtime) reasoning tools. Multicore processors are nowadays widespread across desktop, laptop, server, and even smartphone and tablets devices. The rise of such powerful execution environments...

Due to their complexity and the plethora of requirements placed upon them, healthcare systems so far have not been adequately modeled for the purpose of software development. As a result, the healthcare software suffers from high development costs and lack of flexibility. Model driven software engineering (MDSE) is an emerging methodology for softw...

Multicore processors are nowadays widespread across desktop, laptop, server, and even smartphone and tablets devices. The rise of such powerful execution environments calls for new parallel and distributed Description Logics (DLs) reasoning algorithms. Many sophisticated optimizations have been explored and have considerably enhanced DL reasoning w...

Dealing with the inconsistencies that might arise during the ontology merging process constitutes a major challenge. The explosive nature of classical logic requires any logic-based merging effort to dissolve possible contradictions, and thus maintain consistency. In many cases, however, inconsistent information may be useful for intelligent reason...

A Clinical Practice Guideline defines best practices to be followed by clinicians to manage a particular disease. Checking the quality of such guidelines is a very important issue, e.g., designers of the guidelines should ensure their consistency. A formal modelling approach is an appropriate choice due to the complexity of these guidelines. In thi...

Workflow management systems (WfMS) can be used to manage complex processes, such as those described by Clinical Practise Guidelines (CPG). Such processes involve a variety of stakeholders, however, frequently their interfaces are not suited to the needs of the stakeholders involved. Here we propose that WfMSs be integrated with tools to build a var...

Model driven software engineering (MDSE) is an emerging methodology for software development, targeting productivity, flexibility and reliability of systems; metamodelling is at the core of most MDSE approaches. Due to their complexity and plethora of requirements placed upon them, healthcare systems so far have not been adequately modeled; as a re...

Workflow management tools may be used in many domains, to guide and direct processes, to support monitoring activities and to increase organizational efficiency. In safety critical applications such as healthcare, it is essential that the workflow is error-free, that is, for every run of the workflow, necessary requirements are satisfied and unwant...

Ontology based knowledge management systems have a lot of potential: their applicability ranges from artificial intelligence, e.g., for knowledge representation and natural language processing, to information integration and retrieval systems, requirements analysis, and, most lately, to semantic web applications and workflow management systems. How...

Workflow systems increase productivity and quality of service; however, defects in a workflow model may have severe consequences. While model checking techniques can be used to verify the correctness of a workflow model, these techniques typically suffer from the state explosion problem. We propose a model slicing algorithm with a formal proof to a...

Workflows consist of interconnected tasks which are executed to achieve predefined business goals. When some tasks fail during execution, compensation can be used as an error-handling procedure to remove side-effects of already finished tasks. This paper extends our formal diagrammatic approach to workflow modelling (which uses principles from mode...

Reaching the full potential of the semantic web awaits the availability of highly scalable reasoners. Despite numerous efforts to optimize existing Description Logics reasoners, there is always the need to compromise the expressivity or the size of the used ontologies in time sensitive applications. Hybrid algebraic reasoning has been investigated...

We provide a conceptual model for context aware Semantic Web Service (SWS) discovery, which can utilize real-time legacy data from external systems and support user context-based service discovery and selection. This model offers advantages over current SWS technology which cannot be easily applied to different domains or be integrated with legacy...

In MDE, software systems are always synchronized with their models since changes are made first to the model whenever there are changes in the requirement specifications. While MDE has a lot of potential, it requires maturity and tool support. In this research we present a framework for a workflow management system based on the MDE approach. We pro...

Ontologies are becoming increasingly important in large-scale information systems such as healthcare systems. Ontologies can represent knowledge from clinical guidelines, standards, and practices used in the healthcare sector and may be used to drive decision support systems for healthcare, as well as store data (facts) about patients. Real-life on...

Workflow management systems (WfMSs) are useful tools for supporting enterprise information systems. Such systems must ensure compliance with guidelines and regulations. While formal verification techniques can be used in the development stages to help ensure behavioral properties of many systems, these techniques are generally not available in work...

In this paper we propose a metamodelling approach to behavioural modelling. The approach combines diagrammatic modelling with formal foundations based on category theory and graph transformations. The static semantics of behavioural models is represented by instances of (meta)models, while their dynamic semantics is represented by transition system...

A workflow model is an abstract representation of a real life workflow and consists of interconnected tasks depicting the desired executions of real life activities. Time information is an important aspect of many safety-critical workflows. This paper presents a new formal diagrammatic approach to timed workflow modelling involving principles from...

Model Driven Engineering (MDE) refers to the systematic use of models as primary engineering artifacts throughout the engineering lifecycle. MDE has a lot of potential to make adaptive software systems, but it requires maturity and tool support. Here we present a domain specific language, called T □ (pronounced as T-Square) for writing workflow pro...

Recent efforts towards the Semantic Web have resulted in powerful languages such as Semantic Web Rule Language (SWRL) based on OWL-DL and RuleML. Rule languages and inference engines incorporate reasoning capabilities to Semantic Web application systems. In this paper we present an approach for the design and specification of ontology-driven multi-...

This paper presents the DPFWorkbench, a diagrammatic tool for domain specific modelling. The tool is an implementation of the basic ideas from the Diagram Predicate Framework (DPF), which provides a graph based formalisation of (meta)modelling and model transformations. The DPFWorkbench consists of a specification editor and a signature editor and...

Safety critical systems often consist of many complex processes. Monitoring the behaviour of such processes is critical for enforcing policies, and achieving efficiency and reliability goals. The paper presents a new graphical language for modeling monitors for time constrained workflow processes. To ensure the correctness of a monitor system, we p...

There is a need to better understand the specific settings in which health information technology (HIT) is used and implemented. Factors that will determine the successful implementation of HIT are context-specific and often reside not at the technical level but rather at the process and people level. This paper provides the results of a needs asse...

Over the years, researchers have investigated how to provide better support for hospital administration, therapy and laboratory workflows. Among these efforts, as with any other safety critical system, reliability of the workflows is a key issue. In this paper, we provide a method to enhance the reliability of real world workflows by incorporating...

We present the NOVA Workflow tool-suite, a prototype for a process, information and communication management tool to guide and inform real world workflows with special attention to the needs of health services delivery. NOVA Workflow is an innovative workflow management system which integrates formal verification into the software development proce...

Healthcare workflows (careflows) involve complex, distributive processes with a high degree of variability. There are ubiquitous communication and enormous data and knowledge management requirements and the processes involve complex timing requirements, and are safety critical. Designing these processes and managing their performance is difficult a...

Access control is one of the key features of any health care organization. Without a strong access control mechanism, there is a risk of inappropriate use of personal health information. Here we focus on Personalized Access Control (PAC) [1] where the patient decides who can access his/her health record. We enhance the PAC model of [1] by proposing...

In this paper, we propose the use of an agent-based architecture to enhance workflow system capacity to support interprofessional, patient-centred palliative care delivery. This paper outlines the concept of palliative care and describes how agents can be used to assist care providers to address the needs of the patient and family. Agents are descr...

In recent years, Workflow Management Systems (WfMSs) have been studied and developed to provide automated support for defining and controlling various activities associated with business processes. The automated support reduces costs and overall execution time for business processes, by improving the robustness of the process and increasing product...

In this paper, we give a work-in-progress report of an interdisciplinary partnership among academic researchers, a regional health authority and an industry partner to develop a web-based platform to support a collaborative approach to hospice palliative care. The needs of such a collaborative, community based and patient and family centred program...

Workflows have proven to be a useful conceptualization for the automation of business processes. While formal verification methods (e.g., model checking) can help ensure the reliability of workflow systems, the industrial uptake of such methods has been slow largely due to the effort involved in modeling and the memory required to verify complex s...

In this paper, we propose the use of an agent-based architecture to enhance workflow system capacity to support interprofessional, patient-centred palliative care delivery. This paper outlines the concept of palliative care and describes how agents can be used to assist care providers to address the needs of the patient and family. Our architecture...

Workflow Management Systems (WfMS) that help the design and deployment of automated business processes as well as aid their execution and monitoring continue to evolve. Many WfMS use Workflow Patterns as their basic modeling constructs; however, the absence of verification facilities in most WfMS causes the resulting implementation to be at risk of...

Workflow management systems (WfMSs) have gained increasing attention recently as an important technology to improve information system development in dynamic and distributed organizations. However the absence of verification facilities in most WfMSs causes the resulting implementation of large and complex workflow models to be at risk of undesirabl...

Health care workflows (careflows) involve complex, distributive processes with a high degree of variability. There are ubiquitous communication and massive data and knowledge management requirements and the processes are time sensitive, involve complex timing requirements, and are safety critical. Designing these processes and managing their perfor...

This paper presents an approach to monitor healthcare workflows us-ing a logic-based formal method. We introduce a monitoring architecture with workflows and knowledge bases, and propose a logical language, FO-LTL-K, to express temporal and knowledge properties to be monitored. We formalize some of the norms for palliative care using the proposed l...

Timed model checking, the method to formally verify real-time systems, is attracting increasing attention from both the model checking community and the real-time community. Explicit-time description methods verify real-time systems using general model constructs found in standard un-timed model checkers. Lamport proposed an explicit-time descripti...

Timed model checking has been extensively researched in recent years. Many new formalisms with time extensions and tools based on them have been presented. On the other hand, Explicit-Time Description Methods aim to verify real-time systems with general untimed model checkers. Lamport presented an explicit-time description method using a clock-tick...

Health care systems are prime examples of ultra large scale systems involving complex, distributive processes with a high degree of variability. There are ubiquitous communication and massive data and knowledge management requirements including documentation and reporting. Health care systems are also critical systems, where errors can be very cost...

A major challenge for ontology integration is to effectively deal with inconsistencies that arise during the merging process. Because of the explosive nature of classical logic, the common strategy in existing merging tools is to choose between the contradictory pieces of information and maintain consistency. In many cases inconsistent information...

Workflows describe work processes as sequences of tasks and information regarding who performs them and their relative order. Workflows have been found useful to describe processes in a number of industries. This work focuses on workflows used in health care. Formal verification is the growing field of formalizing and verifying specifications for h...

In order to provide a region based theory of space the notion of Boolean contact algebras has been used. However, not all of the Boolean connectives, in particular complement, are well motivated in that context. A suitable generalization of this theory is to drop the notion of complement, thereby weakening the algebraic structure from a Boolean alg...

A major challenge for ontology integration is to deal with inconsistencies. Existing merging tools are based on classical logic and are forced to avoid inconsistencies (to prevent the logic from becoming explosive) which may cause valuable information loss. However, inconsistent information may serve as an integral component in healthcare systems t...

The theory of Boolean contact algebras has been used to represent a region based theory of space. Some of the primitives of Boolean algebras are not well motivated in that context. One possible generalization is to drop the notion of complement, thereby weakening the algebraic structure from Boolean algebra to distributive lattice. The main goal of...

A calculus of typed relations subsuming the classical relational database theory is presented. An associated sound and complete deduction mechanism is developed. The formulation is generalized to deal with nondeterministic databases and information relations in the rough set-style.

Formal verification is the growing field of formalizing and verifying specifications for hardware and software systems. One such technique, known as model checking, can exhaustively check a software model for properties written in a specification language, such as Linear Temporal Logic (LTL). For large systems, memory reduction techniques are often...

In this paper we describe a procedure for developing models and associated proof systems for two styles of paraconsistent logic. We first give an Urquhart-style representation of bounded not necessarily discrete lattices using (grill, cogrill) pairs. From this we develop Kripke semantics for a logic permitting 3 truth values: true, false and both t...

In earlier work [9], we defined CTL model-checking over finite-valued logics with De Morgan negation. In this paper, we extend this work to logics with intuitionistic, Galois and minimal negations, calling the resulting language χCTL. We define χCTL operators and show that they can be computed using fixpoints. We further discuss how to extend our e...

A calculus of typed relations subsuming the classical relational database theory is presented. An associated sound and complete deduction mechanism is developed. The formulation is generalized to deal with nondeterministic databases and information relations in the rough set-style.

In earlier work [9], we defined CTL model-checking over finite-valued logics with De Morgan negation. In this paper, we extend this work to logics with intuitionistic, Galois and minimal negations, calling the resulting language CTL. We define CTL operators and show that they can be computed using fixpoints. We further discuss how to extend our exi...

This paper presents a categorical formulation for association rules in information systems. MacCaull developed a tableaux style calculus that is sound and complete for the implication problem for association rules. The proof of the completeness required an informational representability result, to go from frames to contexts with 1. To show the comp...

We present a general framework for proof systems for relational theories. We discuss principles of the construction of deduction rules and correspondences reflecting relationships between semantics of relational logics and the rules of the respective proof systems. We illustrate the methods developed in the paper with examples relevant for the Lamb...

Gelfand quantales are complete unital quantales with an involution, *, satisfying the property that for any element a, if a ? b = a for all b, then a ? a* ? a = a. A Hilbert-style axiom system is given for a propositional logic, called Gelfand Logic, which is sound and complete with respect to Gelfand quantales. A Kripke semantics is presented for...

Using a relational approach, we investigate the implication problem for association rules for contexts with 1. We provide sufficient conditions on the relations in an information frame with semistrong relations for the construction of a context with 1. We develop a Rasiowa/Sikorski-style relational calculus which is sound and complete for the impli...

Using a relational approach, we investigate the implication problem for dependencies for information relations, focusing on functional dependencies, association rules and multivalued dependencies. We develop a Rasiowa/Sikorski-style relational calculus and show that the associated tableaux style of reasoning gives a decidable procedure for each of...

We present a uniform relational framework for developing proof systems for theories of manyvaluedness that may have the form of a logical system, of a class of algebra or of an information system. We outline a construction of proof systems for SH_n logics, mv-algebra and many-valued information systems

In this paper we give relational semantics and an accompanying relational proof theory for full Lambek calculus (a sequent calculus which we denote by FL). We start with the Kripke semantics for FL as discussed in [11] and develop a second Kripke-style semantics, RelKripke semantics, as a bridge to relational semantics. The RelKripke semantics cons...

In this paper we give relational semantics and an accompanying relational proof system for a variety of intuitionistic substructural logics, including (intuitionistic) linear logic with exponentials. Starting with the (Kripke-style) semantics for FL as discussed in [13], we developed, in [11], a relational semantics and a relational proof system fo...

We present a procedure for finding matrix models for propositional substructural logics. Each of these logics has algebraic semantics, and the procedure exploits a presentation of the logic for which the algebraic properties of each connective appears as an axiom. The finite nature of the models allows us to exploit features of the semantics that d...

Residuated logic is a generalization of intuitionistic logic, which does not assume the idempotence of the conjunction operator. Such generalized conjunction operators have proved important in expert systems (in the area of Approximate Reasoning) and in some areas of Theoretical Computer Science. Here we generalize the intuitionistic tableau proced...

This research was partially supported by the Natural Sciences and Engineering Council of Canada, grant number A8915, and by the St. Francis Xavier University Council for Research, grant number 1048 Residuated logic is a suitable logical system for approximate reasoning and for the development of fuzzy mathematics. Residuated prepositional logic (RP...

We present Kripke semantics for some substructural logics with weakening, known as logics with BCK implication. This work is a continuation of the work of Allwein and Dunn on Kripke semantics for Linear Logic, which in turn rested on Dunn's Gaggle Theory and on Urquhart's Representation Theory for nondistributive lattices. The basic idea in the rep...

Using finite models to direct the search of an automated theorem prover (through the strategy known as model pruning) can significantly improve the efficiency of theorem provers, which, for nonclassical logics, often suffer from combinatorial explosions. Finding models of size n>4 is itself a difficult problem, as the number of possibilities to che...

Using formally intuitionistic logic coupled with infinitary logic and the completeness theorem for coherent logic, we establish the validity, in Grothendieck toposes, of a number of well-known, classically valid theorems about fields and ordered fields. Classically, these theorems have proofs by contradiction and most involve higher order notions....

Using sheaf semantics, Hilbert's Nullstellensatz is shown to be valid for geometric fields in sheaves over Boolean spaces. From this result, the analogue of the Nullstellensatz for regular rings (first proved in [9]) is easily recovered. Some previous work is then summarized, in which Hilbert's Nullstellensatz is shown to be valid in an arbitrary t...

We investigate some properties of (geometric) fields in toposes of sheaves over Boolean spaces and establish the internal validity of a number of classical theorems from Algebraic Geometry and the theory of ordered fields. We then use our results to obtain, via sheaf representations, some know theorems about (von Neumann) regular rings as well as s...

The diel variations in the assimilation number, P ,', of natural assemblages of coastal ma- rine phytoplankton were examined and a working model proposed to characterize the ap- parent diel rhythm. No rhythm could be distinguished for the initial slope of the light saturation curve, a, although a! and PmB were highly correlated and the daily and ho...

A major challenge for ontology integration is to effectively deal with inconsistencies that arise during the merging process. Because of the explosive nature of classical logic, the common strategy in existing merging tools is to choose between the contradictory pieces of information and maintain consistency. In many cases inconsistent information...

We present the automated theorem prover ReVAT, the implementation of a tableaux- style deduction system applicable to the validity question for (concrete) algebras of binary relations. This system is correct, complete and its implementation provides a semidecision procedure for the validity problem both for algebras of binary relations and also for...

Thesis (M. Sc.)--Dalhousie University, 1976. Includes bibliographical references (leaves 36-40). Microfiche of typescript.