Research Publications

2011

Gerber, M. C., & Gerber, A. . (2011). Towards the Development of Consistent and Unambiguous Financial Accounting Standards using Ontology Technologies. In International Association for Accounting Education & Research. Venice, Italy.

The purpose of accounting is to gather financial data of a business or entity, to interpret this data and to report the results in financial statements to the different users thereof. The interpretation of financial data is regulated by financial accounting standards including an conceptual framework that were developed to facilitate the reporting of financial information of entities so that investors, analysts, creditors as well as the entities themselves can make informed financial decisions. Due to the history as well as some of the mechanisms used to develop the financial accounting standards, conceptual framework and interpretations, inconsistencies and ambiguities are part of the common legacy accountants and auditors are confronted with every day. This is problematic because financial reports have to be clear, concise and unambiguous as the cornerstone of international economies. In order to address the inconsistency problems, the development of unambiguous and principle based financial accounting standards is a key initiative of international financial accounting standards bodies such as the FASB and the IASB at present. This paper is concerned with the question of how recent developments in computer science technologies, specifically within knowledge representation and ontology technologies, could assist in dealing with and eliminating inconsistencies and ambiguities within and between different financial accounting standards. In our research, we developed a formal ontology for some of the basic elements, and in this paper, we report on our findings as well as make some suggestions for a formal approach to the conceptual framework and financial accounting standards development.

@{463,
  author = {Marthinus Gerber and Aurona Gerber},
  title = {Towards the Development of Consistent and Unambiguous Financial Accounting Standards using Ontology Technologies},
  abstract = {The purpose of accounting is to gather financial data of a business or entity, to interpret this data and to report the results in financial statements to the different users thereof. The interpretation of financial data is regulated by financial accounting standards including an conceptual framework that were developed to facilitate the reporting of financial information of entities so that investors, analysts, creditors as well as the entities themselves can make informed financial decisions. Due to the history as well as some of the mechanisms used to develop the financial accounting standards, conceptual framework and interpretations, inconsistencies and ambiguities are part of the common legacy accountants and auditors are confronted with every day. This is problematic because financial reports have to be clear, concise and unambiguous as the cornerstone of international economies. In order to address the inconsistency problems, the development of unambiguous and principle based financial accounting standards is a key initiative of international financial accounting standards bodies such as the FASB and the IASB at present. This paper is concerned with the question of how recent developments in computer science technologies, specifically within knowledge representation and ontology technologies, could assist in dealing with and eliminating inconsistencies and ambiguities within and between different financial accounting standards. In our research, we developed a formal ontology for some of the basic elements, and in this paper, we report on our findings as well as make some suggestions for a formal approach to the conceptual framework and financial accounting standards development.},
  year = {2011},
  journal = {International Association for Accounting Education & Research},
  month = {03/11-05/11},
  address = {Venice, Italy},
}
Bergh, J. ., Gerber, A. ., Meyer, T. ., & van Zijl, L. . (2011). Path analysis for ontology comprehension. Seventh Australasian Ontology Workshop.

n.a.

@misc{462,
  author = {Johann Bergh and Aurona Gerber and Tommie Meyer and Lynette van Zijl},
  title = {Path analysis for ontology comprehension},
  abstract = {n.a.},
  year = {2011},
  journal = {Seventh Australasian Ontology Workshop},
  month = {12/11},
}
Jacobs, D. ., Kotzé, P. ., van der Merwe, A. ., & Gerber, A. . (2011). Enterprise Architecture for Small and Medium Enterprise Growth. In 1st Enterprise Engineering Working Conference . Antwerp, Belgium: Springer, Berlin, Heidelberg. http://doi.org/10.1007/978-3-642-21058-7_5

A key constraint for growing small and medium enterprises (SMEs) is the business skills required to grow the enterprises through the stages of transformation. Criticism against growth stage models for SMEs is of concern, since these models contain the typical knowledge that appeals to managers of small enterprises as guidance in how to manage growth. In this article we propose the SMEAG model to explore the relevance of enterprise architecture (EA) for enhancing existing growth stage models in order to counteract some of this criticism. EA is well-known as a field that claims to manage change and complexity. The rationale to combine the concepts of growth stage models and EA is based on the level of change and complexity associated with the growth of small enterprises into medium enterprises. SMEAG combines the existing growth stage model of Scott and Bruce, the Enterprise Architecture Framework by Hoogervorst, and the EA as Foundation for Business Execution Model by Ross, Weill and Robertson.

@{461,
  author = {Dina Jacobs and Paula Kotzé and Alta van der Merwe and Aurona Gerber},
  title = {Enterprise Architecture for Small and Medium Enterprise Growth},
  abstract = {A key constraint for growing small and medium enterprises (SMEs) is the business skills required to grow the enterprises through the stages of transformation. Criticism against growth stage models for SMEs is of concern, since these models contain the typical knowledge that appeals to managers of small enterprises as guidance in how to manage growth. In this article we propose the SMEAG model to explore the relevance of enterprise architecture (EA) for enhancing existing growth stage models in order to counteract some of this criticism. EA is well-known as a field that claims to manage change and complexity. The rationale to combine the concepts of growth stage models and EA is based on the level of change and complexity associated with the growth of small enterprises into medium enterprises. SMEAG combines the existing growth stage model of Scott and Bruce, the Enterprise Architecture Framework by Hoogervorst, and the EA as Foundation for Business Execution Model by Ross, Weill and Robertson.},
  year = {2011},
  journal = {1st Enterprise Engineering Working Conference},
  pages = {61-75},
  month = {16/05-20/05},
  publisher = {Springer, Berlin, Heidelberg},
  address = {Antwerp, Belgium},
  isbn = {978-3-642-21057-0},
  url = {https://link.springer.com/book/10.1007/978-3-642-21058-7},
  doi = {10.1007/978-3-642-21058-7_5},
}
de Vries, M. ., van der Merwe, A. ., Kotzé, P. ., & Gerber, A. . (2011). Using the Interaction model to compare ontological similarity between business units. In 1st International Conference on Industrial Engineering, Systems Engineering & Engineering Management for Sustainable Global Development. Stellenbosch, Western Cape, South Africa. http://doi.org/10204/5425

Enterprise engineering is an enterprise design methodology that uses a process to create an organised whole, while mastering complexity. Dietz proposes an organisation theorem that reduces complexity by representing the heterogeneous enterprise system as a layered integration of three homogeneous aspect systems: the ontological, infological and datalogical. The ontological aspect system represents the essence of enterprise operation and a starting point for engineering a complex enterprise. This paper applies one of the key ontological models, namely the interaction model, to assess its ability to indentify replication potential due to ontological similarity. The case study environment for application of the interaction model was four departments at a tertiary education institution.

@{460,
  author = {Marne de Vries and Alta van der Merwe and Paula Kotzé and Aurona Gerber},
  title = {Using the Interaction model to compare ontological similarity between business units},
  abstract = {Enterprise engineering is an enterprise design methodology that uses a process to create an organised whole, while mastering complexity. Dietz proposes an organisation theorem that reduces complexity by representing the heterogeneous enterprise system as a layered integration of three homogeneous aspect systems: the ontological, infological and datalogical. The ontological aspect system represents the essence of enterprise operation and a starting point for engineering a complex enterprise. This paper applies one of the key ontological models, namely the interaction model, to assess its ability to indentify replication potential due to ontological similarity. The case study environment for application of the interaction model was four departments at a tertiary education institution.},
  year = {2011},
  journal = {1st International Conference on Industrial Engineering, Systems Engineering & Engineering Management for Sustainable Global Development},
  month = {21/09-23/09},
  address = {Stellenbosch, Western Cape, South Africa},
  doi = {10204/5425},
}
de Vries, M. ., van der Merwe, A. ., Kotzé, P. ., & Gerber, A. . (2011). A Method for Identifying Process Reuse Opportunities to Enhance the Operating Model. In IEEE International Conference on Industrial Engineering and Engineering Management. Changchun, China.

Staying competitive in the 21 st century requires enterprise unity and integration, allowing for agility to accommodate swift changes in strategy as markets evolve and new opportunities emerge. The foundation for execution approach acknowledges the volatility of strategy and suggests the use of an operating model (OM), which is a commitment to a way of doing business. The OM creates a company-wide vision for process standardization and data centralization and guides decisions about how a company implements processes and IT infrastructure. Although the OM provides senior management with a powerful decision-making tool in evolving the current IT landscape, the selection of an appropriate OM requires additional guidance. This article elaborates on current OM deficiencies, requirements for enhancement and a new method, mechanisms and practices to enable an enterprise architecture practitioner to identify the required process reuse opportunities for a specific OM.

@{459,
  author = {Marne de Vries and Alta van der Merwe and Paula Kotzé and Aurona Gerber},
  title = {A Method for Identifying Process Reuse Opportunities to Enhance the Operating Model},
  abstract = {Staying competitive in the 21 st century requires enterprise unity and integration, allowing for agility to accommodate swift changes in strategy as markets evolve and new opportunities emerge. The foundation for execution approach acknowledges the volatility of strategy and suggests the use of an operating model (OM), which is a commitment to a way of doing business. The OM creates a company-wide vision for process standardization and data centralization and guides decisions about how a company implements processes and IT infrastructure. Although the OM provides senior management with a powerful decision-making tool in evolving the current IT landscape, the selection of an appropriate OM requires additional guidance. This article elaborates on current OM deficiencies, requirements for enhancement and a new method, mechanisms and practices to enable an enterprise architecture practitioner to identify the required process reuse opportunities for a specific OM.},
  year = {2011},
  journal = {IEEE International Conference on Industrial Engineering and Engineering Management},
  month = {03/09-05/09},
  address = {Changchun, China},
  isbn = {978-1-4577-0739-1},
}
Nortjé, R. . (2011). Module extraction for inexpressive description logics.

No Abstract

@phdthesis{88,
  author = {Riku Nortjé},
  title = {Module extraction for inexpressive description logics},
  abstract = {No Abstract},
  year = {2011},
  volume = {MSc},
}
Hastings, J. ., & Britz, K. . (2011). Representing chemical structures using OWL and description graphs.

No Abstract

@phdthesis{87,
  author = {J. Hastings and Katarina Britz},
  title = {Representing chemical structures using OWL and description graphs},
  abstract = {No Abstract},
  year = {2011},
  volume = {MSc},
}
Khan, Z. C., & Keet, M. . (2011). Extending ontology development methodologies with foundational ontologies.

From studies, it is clear that using a foundational ontology for domain ontology development is beneficial in theory and practice. However, when it is to be used, developers don't know which one to choose and why. In order to solve this problem, a comprehensive set of criteria that in influence foundational ontology selection has been compiled and a corresponding software tool has been developed to help a domain ontology developer to choose one. This report presents ONSET: a tool used for foundational ontology selection in domain ontology development. Based on an ontology developer's preferences such as ontological commitments, representation languages and other factors, ONSET selects an appropriate foundational ontology to be used for the domain ontology to be developed.

@phdthesis{83,
  author = {Zubeida Khan and Maria Keet},
  title = {Extending ontology development methodologies with foundational ontologies},
  abstract = {From studies, it is clear that using a foundational ontology for domain ontology development is beneficial in theory and practice. However, when it is to be used, developers don't know which one to choose and why. In order to solve this problem, a comprehensive set of criteria that in influence foundational ontology selection has been compiled and a corresponding software tool has been developed to help a domain ontology developer to choose one. This report presents ONSET: a tool used for foundational ontology selection in domain ontology development. Based on an ontology developer's preferences such as ontological commitments, representation languages and other factors, ONSET selects an appropriate foundational ontology to be used for the domain ontology to be developed.},
  year = {2011},
  volume = {Honours},
}
Moodley, K. . (2011). Debugging and Repair of Description Logic Ontologies. Retrieved from http://ksg.meraka.org.za/~kmoodley/MSc%20Dissertation%20-%20KMoodley.pdf

In logic-based Knowledge Representation and Reasoning (KRR), ontologies are used to represent knowledge about a particular domain of interest in a precise way. The building blocks of ontologies include concepts, relations and objects. Those can be combined to form logical sentences which explicitly describe the domain. With this explicit knowledge one can perform reasoning to derive knowledge that is implicit in the ontology. Description Logics (DLs) are a group of knowledge representation languages with such capabilities that are suitable to represent ontologies. The process of building ontologies has been greatly simpli ed with the advent of graphical ontology editors such as SWOOP, Protege and OntoStudio. The result of this is that there are a growing number of ontology engineers attempting to build and develop ontologies. It is frequently the case that errors are introduced while constructing the ontology resulting in undesirable pieces of implicit knowledge that follows from the ontology. As such there is a need to extend current ontology editors with tool support to aid these ontology engineers in correctly designing and debugging their ontologies. Errors such as unsatis able concepts and inconsistent ontologies frequently occur during ontology construction. Ontology Debugging and Repair is concerned with helping the ontology developer to eliminate these errors from the ontology. Much emphasis, in current tools, has been placed on giving explanations as to why these errors occur in the ontology. Less emphasis has been placed on using this information to suggest ecient ways to eliminate the errors. Furthermore, these tools focus mainly on the errors of unsatis able concepts and inconsistent ontologies. In this dissertation we ll an important gap in the area by contributing an alternative approach to ontology debugging and repair for the more general error of a list of unwanted sentences. Errors such as unsatis able concepts and inconsistent ontologies can be represented as unwanted sentences in the ontology. Our approach not only considers the explanation of the unwanted sentences but also the identi cation of repair strategies to eliminate these unwanted sentences from the ontology.

@phdthesis{33,
  author = {Kody Moodley},
  title = {Debugging and Repair of Description Logic Ontologies},
  abstract = {In logic-based Knowledge Representation and Reasoning (KRR), ontologies are used to
represent knowledge about a particular domain of interest in a precise way. The building
blocks of ontologies include concepts, relations and objects. Those can be combined to
form logical sentences which explicitly describe the domain. With this explicit knowledge
one can perform reasoning to derive knowledge that is implicit in the ontology. Description
Logics (DLs) are a group of knowledge representation languages with such capabilities that
are suitable to represent ontologies. The process of building ontologies has been greatly
simplied with the advent of graphical ontology editors such as SWOOP, Protege and
OntoStudio. The result of this is that there are a growing number of ontology engineers
attempting to build and develop ontologies. It is frequently the case that errors are
introduced while constructing the ontology resulting in undesirable pieces of implicit
knowledge that follows from the ontology. As such there is a need to extend current
ontology editors with tool support to aid these ontology engineers in correctly designing
and debugging their ontologies. Errors such as unsatisable concepts and inconsistent
ontologies frequently occur during ontology construction. Ontology Debugging and Repair
is concerned with helping the ontology developer to eliminate these errors from the ontology.
Much emphasis, in current tools, has been placed on giving explanations as to why these
errors occur in the ontology. Less emphasis has been placed on using this information to
suggest ecient ways to eliminate the errors. Furthermore, these tools focus mainly on the
errors of unsatisable concepts and inconsistent ontologies. In this dissertation we ll an
important gap in the area by contributing an alternative approach to ontology debugging
and repair for the more general error of a list of unwanted sentences. Errors such as
unsatisable concepts and inconsistent ontologies can be represented as unwanted sentences
in the ontology. Our approach not only considers the explanation of the unwanted sentences
but also the identication of repair strategies to eliminate these unwanted sentences from
the ontology.},
  year = {2011},
  volume = {MSc},
  url = {http://ksg.meraka.org.za/~kmoodley/MSc%20Dissertation%20-%20KMoodley.pdf},
}
Moodley, K. ., Meyer, T. ., & Varzinczak, I. . (2011). Root Justifications for Ontology Repair. In Fifth International Conference on Web Reasoning and Rule Systems.

No Abstract

@{32,
  author = {Kody Moodley and Tommie Meyer and Ivan Varzinczak},
  title = {Root Justifications for Ontology Repair},
  abstract = {No Abstract},
  year = {2011},
  journal = {Fifth International Conference on Web Reasoning and Rule Systems},
  pages = {275-280},
}
Nortjé, R. ., Britz, K. ., & Meyer, T. . (2011). Bidirectional reachability-based modules. 24th International Workshop on Description Logics (DL 2011).

We introduce an algorithm for MinA extraction in EL based on bidirectional reachability. We obtain a significant reduction in the size of modules extracted at almost no additional cost to that of extracting standard reachability-based modules. Bidirectional modules are related to nested locality modules, but are aimed specifically at MinA extraction and are generally smaller. For acyclic EL TBoxes consisting of only primitive concept inclusions, all MinAs can be extracted without the need for subsumption testing.

@misc{30,
  author = {Riku Nortjé and Katarina Britz and Tommie Meyer},
  title = {Bidirectional reachability-based modules},
  abstract = {We introduce an algorithm for MinA extraction in EL based on bidirectional reachability. We obtain a significant reduction in the size of modules extracted at almost no additional cost to that of extracting standard reachability-based modules. Bidirectional modules are related to nested locality modules, but are aimed specifically at MinA extraction and are generally smaller. For acyclic EL TBoxes consisting of only primitive concept inclusions, all MinAs can be extracted without the need for subsumption testing.},
  year = {2011},
  journal = {24th International Workshop on Description Logics (DL 2011)},
  month = {13/07 - 16/07},
}
Halland, K. ., Britz, K. ., & Gerber, A. . (2011). Investigations into the use of SNOMED CT to enhance an Open-MRS health information system. South African Computer Journal, 47.

No Abstract

@article{29,
  author = {Ken Halland and Katarina Britz and Aurona Gerber},
  title = {Investigations into the use of SNOMED CT to enhance an Open-MRS health information system},
  abstract = {No Abstract},
  year = {2011},
  journal = {South African Computer Journal},
  volume = {47},
  pages = {33-46},
}
Britz, K. ., Meyer, T. ., & Varzinczak, I. . (2011). Concept Model Semantics for DL Preferential Reasoning. 24th International Workshop on Description Logics (DL 2011).

The preferential and rational consequence relations first studied by Lehmann and colleagues play a central role in non-monotonic reasoning, not least because they provide the foundation for the determination of the important notion of rational closure. Although they can be applied directly to a large variety of logics, these constructions suffer from the limitation that they are largely propositional in nature. One of the main obstacles in moving beyond the propositional case has been the lack of a formal semantics which appropriately generalizes the preferential and ranked models of Lehmann et al. In this paper we propose a semantics to fill that gap for description logics, an important class of decidable fragments of first-order logic. Our semantics replaces the propositional valuations used in the models of Lehmann et al. with structures we refer to as concept models. We prove representation results for the description logic ALC for both preferential and rational consequence relations. We argue that our semantics paves the way for extending preferential and rational consequence, and therefore also rational closure, to a whole class of logics that have a semantics defined in terms of first-order relational structures.

@misc{28,
  author = {Katarina Britz and Tommie Meyer and Ivan Varzinczak},
  title = {Concept Model Semantics for DL Preferential Reasoning},
  abstract = {The preferential and rational consequence relations first studied by Lehmann and colleagues play a central role in non-monotonic reasoning, not least because they provide the foundation for the determination of the important notion of rational closure. Although they can be applied directly to a large variety of logics, these constructions suffer from the limitation that they are largely propositional in nature. One of the main obstacles in moving beyond the propositional case has been the lack of a formal semantics which appropriately generalizes the preferential and ranked models of Lehmann et al. In this paper we propose a semantics to fill that gap for description logics, an important class of decidable fragments of first-order logic. Our semantics replaces the propositional valuations used in the models of Lehmann et al. with structures we refer to as concept models. We prove representation results for the description logic ALC for both preferential and rational consequence relations. We argue that our semantics paves the way for extending preferential and rational consequence, and therefore also rational closure, to a whole class of logics that have a semantics defined in terms of first-order relational structures.},
  year = {2011},
  journal = {24th International Workshop on Description Logics (DL 2011)},
  month = {13/07 - 16/07},
}
Britz, K. ., Meyer, T. ., & Varzinczak, I. . (2011). Semantic Foundation for Preferential Description Logics. In Proceedings of the 24th Australasian Joint Conference on Artificial Intelligence.

Description logics are a well-established family of knowledge representation formalisms in Artificial Intelligence. Enriching description logics with non-monotonic reasoning capabilities, especially preferential reasoning as developed by Lehmann and colleagues in the 90's, would therefore constitute a natural extension of such KR formalisms. Nevertheless, there is at present no generally accepted semantics, with corresponding syntactic characterization, for preferential consequence in description logics. In this paper we fill this gap by providing a natural and intuitive semantics for defeasible subsumption in the description logic ALC. Our semantics replaces the propositional valuations used in the models of Lehmann et al. with structures we refer to as concept models. We present representation results for the description logic ALC for both preferential and rational consequence relations. We argue that our semantics paves the way for extending preferential and rational consequence, and therefore also rational closure, to a whole class of logics that have a semantics defined in terms of first-order relational structures.

@{27,
  author = {Katarina Britz and Tommie Meyer and Ivan Varzinczak},
  title = {Semantic Foundation for Preferential Description Logics},
  abstract = {Description logics are a well-established family of knowledge representation formalisms in Artificial Intelligence. Enriching description logics with non-monotonic reasoning capabilities, especially preferential reasoning as developed by Lehmann and colleagues in the 90's, would therefore constitute a natural extension of such KR formalisms. Nevertheless, there is at present no generally accepted semantics, with corresponding syntactic characterization, for preferential consequence in description logics. In this paper we fill this gap by providing a natural and intuitive semantics for defeasible subsumption in the description logic ALC. Our semantics replaces the propositional valuations used in the models of Lehmann et al. with structures we refer to as concept models. We present representation results for the description logic ALC for both preferential and rational consequence relations. We argue that our semantics paves the way for extending preferential and rational consequence, and therefore also rational closure, to a whole class of logics that have a semantics defined in terms of first-order relational structures.},
  year = {2011},
  journal = {Proceedings of the 24th Australasian Joint Conference on Artificial Intelligence},
  pages = {491-500},
}
Meyer, T. ., & Varzinczak, I. . (2011). A Logic-Based Perspective on Agent Reconfiguration: Preliminary Report. In IEEE Africon.

We investigate the problem of maintaining and reasoning with different configurations of a logic-based agent. Given specific contexts, there may be several possible usual configurations that the agent's knowledge base can be in, and that one may want to access at different times. This can happen due to foreseeable exceptional situations one has to cater for, or different environments in which the agent may have to operate, or simply due to upgrades of the agent's initial configuration. In all these cases, there is a need for a system capable of managing possibly conflicting versions of the knowledge base and allowing the agent to switch between any two given configurations at run time. Building on Franconi et al.'s framework for propositional knowledge base versioning, here we establish the logical foundations for a general semantic-based architecture of such a system. Central to our approach is the notion of logical difference, which allows us to determine the essential pieces of information on which two given configurations of an agent differ.

@{26,
  author = {Tommie Meyer and Ivan Varzinczak},
  title = {A Logic-Based Perspective on Agent Reconfiguration: Preliminary Report},
  abstract = {We investigate the problem of maintaining and reasoning with different configurations of a logic-based agent. Given specific contexts, there may be several possible usual configurations that the agent's knowledge base can be in, and that one may want to access at different times. This can happen due to foreseeable exceptional situations one has to cater for, or different environments in which the agent may have to operate, or simply due to upgrades of the agent's initial configuration. In all these cases, there is a need for a system capable of managing possibly conflicting versions of the knowledge base and allowing the agent to switch between any two given configurations at run time. Building on Franconi et al.'s framework for propositional knowledge base versioning, here we establish the logical foundations for a general semantic-based architecture of such a system. Central to our approach is the notion of logical difference, which allows us to determine the essential pieces of information on which two given configurations of an agent differ.},
  year = {2011},
  journal = {IEEE Africon},
}
Britz, K. ., Heidema, J. ., & Varzinczak, I. . (2011). Constrained Consequence. Logica Universalis, 5(2).

There are various contexts in which it is not pertinent to generate and attend to all the classical consequences of a given premiss—or to trace all the premisses which classically entail a given consequence. Such contexts may involve limited resources of an agent or inferential engine, contextual relevance or irrelevance of certain consequences or premisses, modelling everyday human reasoning, the search for plausible abduced hypotheses or potential causes, etc. In this paper we propose and expli- cate one formal framework for a whole spectrum of consequence relations, flexible enough to be tailored for choices from a variety of contexts. We do so by investigating semantic constraints on classical entailment which give rise to a family of infra-classical logics with appealing properties. More specifically, our infra-classical reasoning demands (beyond α |= β) that Mod(β) does not run wild, but lies within the scope (whatever that may mean in some specific context) of Mod(α), and which can be described by a sentence •α with β |= •α. Besides being infra-classical, the resulting logic is also non-monotonic and allows for non-trivial reasoning in the presence of inconsistencies.

@article{25,
  author = {Katarina Britz and J. Heidema and Ivan Varzinczak},
  title = {Constrained Consequence},
  abstract = {There are various contexts in which it is not pertinent to generate and attend to all the classical consequences of a given premiss—or to trace all the premisses which classically entail a given consequence. Such contexts may involve limited resources of an agent or inferential engine, contextual relevance or irrelevance of certain consequences or premisses, modelling everyday human reasoning, the search for plausible abduced hypotheses or potential causes, etc. In this paper we propose and expli- cate one formal framework for a whole spectrum of consequence relations, flexible enough to be tailored for choices from a variety of contexts. We do so by investigating semantic constraints on classical entailment which give rise to a family of infra-classical logics with appealing properties. More specifically, our infra-classical reasoning demands (beyond α |= β) that Mod(β) does not run wild, but lies within the scope (whatever that may mean in some specific context) of Mod(α), and which can be described by a sentence •α with β |= •α. Besides being infra-classical, the resulting logic is also non-monotonic and allows for non-trivial reasoning in the presence of inconsistencies.},
  year = {2011},
  journal = {Logica Universalis},
  volume = {5},
  pages = {327-350},
  issue = {2},
}
Booth, R. ., Meyer, T. ., Varzinczak, I. ., & Wassermann, R. . (2011). On the Link between Partial Meet, Kernel, and Infra Contraction and its Application to Horn Logic. Journal of Artificial Intelligence Research, 42.

Standard belief change assumes an underlying logic containing full classical propositional logic. However, there are good reasons for considering belief change in less expressive logics as well. In this paper we build on recent investigations by Delgrande on contraction for Horn logic. We show that the standard basic form of contraction, partial meet, is too strong in the Horn case. This result stands in contrast to Delgrande's conjecture that orderly maxichoice is the appropriate form of contraction for Horn logic. We then define a more appropriate notion of basic contraction for the Horn case, influenced by the convexity property holding for full propositional logic and which we refer to as infra contraction. The main contribution of this work is a result which shows that the construction method for Horn contraction for belief sets based on our infra remainder sets corresponds exactly to Hansson's classical kernel contraction for belief sets, when restricted to Horn logic. This result is obtained via a detour through contraction for belief bases. We prove that kernel contraction for belief bases produces precisely the same results as the belief base version of infra contraction. The use of belief bases to obtain this result provides evidence for the conjecture that Horn belief change is best viewed as a 'hybrid' version of belief set change and belief base change. One of the consequences of the link with base contraction is the provision of a representation result for Horn contraction for belief sets in which a version of the Core-retainment postulate features.

@article{24,
  author = {Richard Booth and Tommie Meyer and Ivan Varzinczak and R. Wassermann},
  title = {On the Link between Partial Meet, Kernel, and Infra Contraction and its Application to Horn Logic},
  abstract = {Standard belief change assumes an underlying logic containing full classical propositional logic. However, there are good reasons for considering belief change in less expressive logics as well. In this paper we build on recent investigations by Delgrande on contraction for Horn logic. We show that the standard basic form of contraction, partial meet, is too strong in the Horn case. This result stands in contrast to Delgrande's conjecture that orderly maxichoice is the appropriate form of contraction for Horn logic. We then define a more appropriate notion of basic contraction for the Horn case, influenced by the convexity property holding for full propositional logic and which we refer to as infra contraction. The main contribution of this work is a result which shows that the construction method for Horn contraction for belief sets based on our infra remainder sets corresponds exactly to Hansson's classical kernel contraction for belief sets, when restricted to Horn logic. This result is obtained via a detour through contraction for belief bases. We prove that kernel contraction for belief bases produces precisely the same results as the belief base version of infra contraction. The use of belief bases to obtain this result provides evidence for the conjecture that Horn belief change is best viewed as a 'hybrid' version of belief set change and belief base change. One of the consequences of the link with base contraction is the provision of a representation result for Horn contraction for belief sets in which a version of the Core-retainment postulate features.},
  year = {2011},
  journal = {Journal of Artificial Intelligence Research},
  volume = {42},
  pages = {31-53},
}
Britz, K. ., Meyer, T. ., & Varzinczak, I. . (2011). Preferential Reasoning for Modal Logic. Electronic Notes in Theoretical Computer Science, 278.

Modal logic is the foundation for a versatile and well-established class of knowledge representation formalisms in artificial intelligence. Enriching modal logics with non-monotonic reasoning capabilities such as preferential reasoning as developed by Lehmann and colleagues would therefore constitute a natural extension of such KR formalisms. Nevertheless, there is at present no generally accepted semantics, with corresponding syntactic characterization, for preferential consequence in modal logics. In this paper we fill this gap by providing a natural and intuitive semantics for preferential and rational modal consequence. We do so by placing a preference order on possible worlds indexed by Kripke models they belong to. We also prove representation results for both preferential and rational consequence, which paves the way for effective decision procedures for modal preferential reasoning. We then illustrate applications of our constructions to modal logics widely used in AI, notably in the contexts of reasoning about actions, knowledge and beliefs. We argue that our semantics constitutes the foundation on which to explore preferential reasoning in modal logics in general.

@article{23,
  author = {Katarina Britz and Tommie Meyer and Ivan Varzinczak},
  title = {Preferential Reasoning for Modal Logic},
  abstract = {Modal logic is the foundation for a versatile and well-established class of knowledge representation formalisms in artificial intelligence. Enriching modal logics with non-monotonic reasoning capabilities such as preferential reasoning as developed by Lehmann and colleagues would therefore constitute a natural extension of such KR formalisms. Nevertheless, there is at present no generally accepted semantics, with corresponding syntactic characterization, for preferential consequence in modal logics. In this paper we fill this gap by providing a natural and intuitive semantics for preferential and rational modal consequence. We do so by placing a preference order on possible worlds indexed by Kripke models they belong to. We also prove representation results for both preferential and rational consequence, which paves the way for effective decision procedures for modal preferential reasoning. We then illustrate applications of our constructions to modal logics widely used in AI, notably in the contexts of reasoning about actions, knowledge and beliefs. We argue that our semantics constitutes the foundation on which to explore preferential reasoning in modal logics in general.},
  year = {2011},
  journal = {Electronic Notes in Theoretical Computer Science},
  volume = {278},
  pages = {55-69},
}
Booth, R. ., & Meyer, T. . (2011). Belief Change. In Logic and Philosophy Today, Vol. 1, Studies in Logic, Vol. 29. College Publications. Retrieved from www.collegepublications.co.uk/logic/mlf/?00017

In this paper we present a brief overview of belief change, a research area concerned with the question of how a rational agent ought to change its mind in the face of new, possibly conflicting, information. We limit ourselves to logic-based belief change, with a particular emphasis on classical propositional logic as the underlying logic in which beliefs are to be represented. Our intention is to provide the reader with a basic introduction to the work done in this area over the past 30 years. In doing so we hope to sketch the main historical results, provide appropriate pointers to further references, and discuss some current developments. We trust that this will spur on the interested reader to learn more about the topic, and perhaps to join us in the further development of this exciting field of research.

@inbook{17,
  author = {Richard Booth and Tommie Meyer},
  title = {Belief Change},
  abstract = {In this paper we present a brief overview of belief change, a research area concerned with the question of how a rational agent ought to change its mind in the face of new, possibly conflicting, information. We limit ourselves to logic-based belief change, with a particular emphasis on classical propositional logic as the underlying logic in which beliefs are to be represented. Our intention is to provide the reader with a basic introduction to the work done in this area over the past 30 years. In doing so we hope to sketch the main historical results, provide appropriate pointers to further references, and discuss some current developments. We trust that this will spur on the interested reader to learn more about the topic, and perhaps to join us in the further development of this exciting field of research.},
  year = {2011},
  journal = {Logic and Philosophy Today, Vol. 1, Studies in Logic, Vol. 29},
  pages = {385-422},
  publisher = {College Publications},
  url = {www.collegepublications.co.uk/logic/mlf/?00017},
}
Hajek, M. ., & Singh, Y. . (2011). Medical AI - HIV/AIDS Treatment Management System. In Beyond AI: Interdisciplinary Aspects of Artificial Intelligence.

Medical AI has established itself as a robust and fruitful field in the last 30 years. Most resource poor countries face the triple burden of malaria, tuberculosis and HIV. This coupled with the problems of lack of infrastructure, scarcity of clinical staff, and complex clinical guidelines, have encouraged the application of AI in healthcare specifially on practical issues of field medical data collection, mining, and better integration with healthcare workfow. One such application is an HIV/AIDS antiretroviral therapy management system that uses AI algorithm to predict drug resistance and the progression of the disease. Another serious problem is the scarcity of personnel with sucient AI knowledge in the medical field. A distance education has shown its potential to remedy the problem.

@{15,
  author = {Milan Hajek and Y. Singh},
  title = {Medical AI - HIV/AIDS Treatment Management System},
  abstract = {Medical AI has established itself as a robust and fruitful field in the last 30 years. Most resource poor countries face the triple burden of malaria, tuberculosis and HIV. This coupled with the problems of lack of infrastructure, scarcity of clinical staff, and complex clinical guidelines, have encouraged the application of AI in healthcare specifially on practical issues of field medical data collection, mining, and better integration with healthcare workfow. One such application is an HIV/AIDS antiretroviral therapy management system that uses AI algorithm to predict drug resistance and the progression of the disease. Another serious problem is the scarcity of personnel with sucient AI knowledge in the medical field. A distance education has shown its potential to remedy the problem.},
  year = {2011},
  journal = {Beyond AI: Interdisciplinary Aspects of Artificial Intelligence},
}
Gous, H. ., Gard, J. ., & Gerber, A. . (2011). Business architecture for inter-organisational innovation networks: A case study comparison from South Africa and Germany. In ICE 2011.

The range of inter-organisational innovation networks existing in the global economy today show a wide variance in structure, purpose, location, lifespan and maturity. These differences between network instantiations highlight the need for deeper understanding of the operation of these networks in order to enable efforts to improve network performance. These efforts include strategic management routines for network leadership, as well as the development of appropriate support structures, e.g. information systems architectures. An important step towards a deeper understanding of inter-organisational innovation networks is to compare the business architectures of network case studies to identify similarities and differences in terms of scope and context, business concepts and underlying system logic. The Zachman framework for enterprise architecture provides an approach to structuring the business architecture of enterprises in a way that allows such comparisons to be drawn. This paper describes the business architecture of two contrasting network case studies from South Africa and Germany within the Zachman framework, and draws some conclusions based on the observed similarities and conclusions.

@{14,
  author = {Henno Gous and J. Gard and Aurona Gerber},
  title = {Business architecture for inter-organisational innovation networks:  A case study comparison from South Africa and Germany},
  abstract = {The range of inter-organisational innovation networks existing in the global economy today show a wide variance in structure, purpose, location, lifespan and maturity. These differences between network instantiations highlight the need for deeper understanding of the operation of these networks in order to enable efforts to improve network performance. These efforts include strategic management routines for network leadership, as well as the development of appropriate support structures, e.g. information systems architectures.
An important step towards a deeper understanding of inter-organisational innovation networks is to compare the business architectures of network case studies to identify similarities and differences in terms of scope and context, business concepts and underlying system logic. The Zachman framework for enterprise architecture provides an approach to structuring the business architecture of enterprises in a way that allows such comparisons to be drawn. This paper describes the business architecture of two contrasting network case studies from South Africa and Germany within the Zachman framework, and draws some conclusions based on the observed similarities and conclusions.},
  year = {2011},
  journal = {ICE 2011},
}
Moodley, D. ., & Tapamo, J. R. (2011). A semantic infrastructure for a Knowledge Driven Sensor Web. In Proceedings of the 4th International Workshop on Semantic Sensor Networks 2011 (SSN11), 23 October 2011,Bonn, Germany, A workshop of the 10th International Semantic Web Conference (ISWC 2011).

No Abstract

@{9,
  author = {Deshen Moodley and J. Tapamo},
  title = {A semantic infrastructure for a Knowledge Driven Sensor Web},
  abstract = {No Abstract},
  year = {2011},
  journal = {Proceedings of the 4th International Workshop on Semantic Sensor Networks 2011 (SSN11), 23 October 2011,Bonn, Germany,  A workshop of the 10th International Semantic Web Conference (ISWC 2011)},
}

2010

Gerber, A. ., van der Merwe, A. ., & Kotzé, P. . (2010). Towards the Formalisation of the TOGAF Content Metamodel using Ontologies. In 12th International Conference on Enterprise Information Systems (ICEIS). Funchal, Madeira, Portugal. http://doi.org/10204/4075

Metamodels are abstractions that are used to specify characteristics of models. Such metamodels are generally included in specifications or framework descriptions. A metamodel is for instance used to inform the generation of enterprise architecture content in the Open Group’s TOGAF 9 Content Metamodel description. However, the description of metamodels is usually done in an ad-hoc manner with customised languages and this often results in ambiguities and inconsistencies. The authors are concerned with the question of how the quality of metamodel descriptions, specifically within the enterprise architecture domain, could be enhanced. Therefore we investigated whether formal ontology technologies could be used to enhance metamodel construction, specification and design. For this research, the authors constructed a formal ontology for the TOGAF 9 Content Metamodel, and in the process, gained valuable insight into metamodel quality. In particular, the current TOGAF 9 Content Metamodel contains ambiguities and inconsistencies, which could be eliminated using ontology technologies. In this paper the authors argue for the integration of formal ontologies and ontology technologies as tools into metamodel construction and specification. Ontologies allow for the construction of complex conceptual models, but more significant, ontologies can assist an architect by depicting all the consequences of a model, allowing for more precise and complete artifacts within enterprise architectures, and because these models use standardized languages, they should promote integration and interoperability.

@{469,
  author = {Aurona Gerber and Alta van der Merwe and Paula Kotzé},
  title = {Towards the Formalisation of the TOGAF Content Metamodel using Ontologies},
  abstract = {Metamodels are abstractions that are used to specify characteristics of models. Such metamodels are generally included in specifications or framework descriptions. A metamodel is for instance used to inform the generation of enterprise architecture content in the Open Group’s TOGAF 9 Content Metamodel description. However, the description of metamodels is usually done in an ad-hoc manner with customised languages and this often results in ambiguities and inconsistencies. The authors are concerned with the question of how the quality of metamodel descriptions, specifically within the enterprise architecture domain, could be enhanced. Therefore we investigated whether formal ontology technologies could be used to enhance metamodel construction, specification and design. For this research, the authors constructed a formal ontology for the TOGAF 9 Content Metamodel, and in the process, gained valuable insight into metamodel quality. In particular, the current TOGAF 9 Content Metamodel contains ambiguities and inconsistencies, which could be eliminated using ontology technologies. In this paper the authors argue for the integration of formal ontologies and ontology technologies as tools into metamodel construction and specification. Ontologies allow for the construction of complex conceptual models, but more significant, ontologies can assist an architect by depicting all the consequences of a model, allowing for more precise and complete artifacts within enterprise architectures, and because these models use standardized languages, they should promote integration and interoperability.},
  year = {2010},
  journal = {12th International Conference on Enterprise Information Systems (ICEIS)},
  pages = {54-64},
  month = {08/06-12/06},
  address = {Funchal, Madeira, Portugal},
  doi = {10204/4075},
}
de Vries, M. ., van der Merwe, A. ., Gerber, A. ., & Kotzé, P. . (2010). Refining The Operating Model Concept To Enable Systematic Growth In Operating Maturity. In 24th Anuual SAIIE Conference. Muldersdrift, South Africa. http://doi.org/10204/4572

To stay competitive, enterprises of today need to rely on a sound foundation for execution that incorporates the infrastructure and digitised processes for automating a company’s core capabilities. Once this foundation has been established, management could move their attention away from focusing on lower-value activities to innovative ways to increase profits and growth. The Business-IT Alignment Framework (BIAF) defines business-IT alignment in terms of a paradigm of alignment, three dimensions for alignment, and mechanisms and practices. The BIAF could provide a business-IT alignment perspective on the foundation for execution approach. Using the BIAF perspective, this paper comments on some of the deficiencies related to the foundation for execution approach regarding the systematic identification of opportunities for enterprise-wide process standardisation. The goal is to define a list of requirements that should direct the design of appropriate mechanisms and practices to address the identification of process re-use opportunities for multiple levels of operating maturity.

@{468,
  author = {Marne de Vries and Alta van der Merwe and Aurona Gerber and Paula Kotzé},
  title = {Refining The Operating Model Concept To Enable Systematic Growth In Operating Maturity},
  abstract = {To stay competitive, enterprises of today need to rely on a sound foundation for execution that incorporates the infrastructure and digitised processes for automating a company’s core capabilities. Once this foundation has been established, management could move their attention away from focusing on lower-value activities to innovative ways to increase profits and growth. The Business-IT Alignment Framework (BIAF) defines business-IT alignment in terms of a paradigm of alignment, three dimensions for alignment, and mechanisms and practices. The BIAF could provide a business-IT alignment perspective on the foundation for execution approach. Using the BIAF perspective, this paper comments on some of the deficiencies related to the foundation for execution approach regarding the systematic identification of opportunities for enterprise-wide process standardisation. The goal is to define a list of requirements that should direct the design of appropriate mechanisms and practices to address the identification of process re-use opportunities for multiple levels of operating maturity.},
  year = {2010},
  journal = {24th Anuual SAIIE Conference},
  month = {6/10-8/10},
  address = {Muldersdrift, South Africa},
  doi = {10204/4572},
}
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