Laurette Pretorius

Facial animation in a nutshell: past, present and future

During its almost forty years of existence, facial animation has seen a host of technologies being invented, then fading into obsolescence. The modelling and animation methods have mostly been dictated by the available hardware, which greatly evolved through the years. Many animation desiderata that have been considered dreams at the time are now reality while ever new frontiers are encountered and explored. This paper provides an overview of the historically used technologies and attempts to predict the future trends in the field of facial animation as it permeates the entertainment industry with its feature films and computer games; the broad field of visualisation in science, including medical science and forensic analysis; and the fast growing field of information and communication technology and human-computer interaction.

Multilingual Verbalisation of Modular Ontologies Using GF and lemon

This paper presents an approach to multilingual ontology verbalisation of controlled language based on the Grammatical Framework (GF) and the lemon model. It addresses specific challenges that arise when classes are used to create a consensus-based conceptual framework, in which many parties individually contribute instances. The approach is presented alongside a concrete case, in which ontologies are used to capture business processes by linguistically untrained stakeholders across business disciplines. GF is used to create multilingual grammars that enable transparent multilingual verbalisation. Capturing the instance labels in lemon lexicons reduces the need for GF engineering to the class level: The lemon lexicons with the labels of the instances are converted into GF grammars based on a mapping described in this paper. The grammars are modularised in accordance with the ontology modularisation and can deal with the different styles of label choosing that occur in practice.

Integrating Computer Ethics into the Computing Curriculum: A Framework for Implementation

The advent of the Information Age and global connectivity has placed ethics center stage in the use of Information and Communication Technologies (ICT). As the drive towards the establishment of a socalled IT profession gains momentum, ethical conduct and codes of ethics have recently been formulated and introduced formally. Initiatives in this regard can be attributed to, among others, the ACM and the IEEE. Of particular significance is the ImpactCS Project commissioned by the joint taskforce of the ACM and IEEE, and funded by the USA’s National Science Foundation. The increased globalization and inherent nature of ICT transcend physical and cultural borders, making it increasingly difficult to enforce accepted laws, regulations, and codes of conduct. It is thus the responsibility of Computer Science and Information Systems instructors to teach and instill professional values and ethical analysis skills in each and every student. Therefore, we investigate some issues pertaining to the teaching of computer ethics. We conclude this paper by presenting a possible framework to be used in the teaching of computer ethics, and apply this framework to our own institution.

Introduction to the special issue on African Language Technology

In today’s digital multilingual world, language technology is crucial for providing access to information and opportunities for economic development. With approximately two thousand different languages, Africa is a multilingual continent par excellence, presenting acute challenges for those seeking to promote and use African languages in the areas of business development, education and relief aid. In recent times a number of researchers and institutions, both from Africa and elsewhere, have come forward to share the common goal of developing capabilities in language technology for African languages. In 2009 and 2010, the first two workshops on African Language Technology were organized (De Pauw et al. 2009, 2010a) as a forum to bring together a wide range of researchers working in this domain.

Containing overgeneration in Zulu computational morphology

The development of a large-coverage, computational morphological analyser for Zulu requires the modelling not only of the regular phenomena often associated with word formation, but also the idiosyncratic behaviour that may occur in Zulu morphology. This paper discusses the application of an existing rule-based, finite-state morphological analyser prototype ZulMorph in semi-automating the mining of available Zulu language corpora for idiosyncratic behaviour. The semi-automated procedure makes provision for bootstrapping the morphological analyser to include newly extracted information from corpora. Of particular interest is also the central role that the machine-readable lexicon plays. The procedure is applied to a Zulu development corpus of 30 000 types and the results are given and discussed.

Finite state morphology of the nguni language cluster: modelling and implementation issues

The paper provides an overview of a project on computational morphological analysers for the Nguni cluster of languages namely Zulu, Xhosa, Swati and Ndebele. These languages are agglutinative and lesser-resourced. The project adopted a finite approach, which is wellsuited to modelling both regular morphophonological phenomena and linguistic idiosyncrasies. The paper includes a brief overview of the morphology of this cluster of languages, then focuses on how the various morphophonological phenomena of Zulu are modelled and implemented using the Xerox finite-state toolkit. The bootstrapping of the Zulu morphological analyser prototype, ZulMorph, to obtain analyser prototypes for Xhosa, Swati and Ndebele, is outlined and experimental results given.

Multiple object agreement morphemes in Setswana: a computational approach

Abstract Setswana is an agglutinative language where prefixes and suffixes are extensively used in the formation of words. Words such as verbs, pronouns, adjectives and so on, which have a grammatical relationship with nouns in sentences, demonstrate agreement with such nouns by means of agreement morphemes. In certain instances verbs in Setswana sentences may take two objects. Both of these objects may be represented in the verb by object agreement morphemes. The result is that two object agreement morphemes may be prefixed to the verb. While the morphemes of the verb are presented systematically in Setswana grammars, the occurrence of multiple object agreement morphemes has received limited attention in the literature on Setswana linguistics. Similarly, this phenomenon has not yet been investigated from a computational morphological point of view. This article reports on (i) an example-based investigation towards a better and more complete understanding of the phenomenon of multiple object agreement morphemes as they appear in Setswana verbs, (ii) the modelling of these morphemes in an existing finite state tokeniser and computational morphological analyser for Setswana, and (iii) the novel role that a morphological analyser and its guesser variant can play in a corpus-based investigation of the phenomenon under discussion.

Engineering RESTful semantic services on the fly

Real-world implementations of semantic services that could enable seamless integration of heterogeneous systems on the fly are deficient. This could be attributed to the complexity of heavy-weight semantic technologies, which mostly have a steep learning curve. As a consequence, the evolvement of modern approaches that purport to simplify the engineering of such services is a necessity. In this short paper, we present a work-in-progress model-driven approach that seeks to simplify and speed up the process of engineering RESTful semantic services. The suggested approach promotes automatic transformation of platform independent service models to partial service implementation and semantic descriptions to realize functional RESTful semantic services. The proposed solution is demonstrated and evaluated through a simple use-case scenario.

Toward a service creation framework: a case of intelligent semantic services

Semantic Web Services are touted as one possible solution for some of the challenges experienced with Web services; such as lack of automatic service discovery and consumption. Ideally, semantic services are meant to facilitate automatic business service provisioning and consumption on the Web. These services are enriched with semantics, which are derived from ontologies. Nevertheless, semantic-based services are scarcely adopted and utilised by service providers and consumers respectively. Some of the reasons noted in literature for this lack of adoption and usage include issues such as lack of real-life prototypes that are meant to demonstrate the benefits of semantic services; lack of integrated service creation frameworks; and unified development platforms that are purported to guide and promote simple engineering of semantic services. Thus, in this short paper our aim is on the proposal and presentation of a conceptual multi-layered and yet integrated service creation framework called iSemServ. The framework is intended to guide, simplify, and accelerate the process of engineering intelligent semantic services.

A finite state approach to setswana verb morphology

Setswana is characterised by a disjunctive orthography according to which verbal prefixal morphemes are usually written disjunctively, while suffixal morphemes to the verb root follow a conjunctive writing style. This article specifically focusses on a finite-state approach to Setswana verb morphology and the challenges of the disjunctive orthography used for prefixes.