We live in a cultural environment in which computer based musical performances have become ubiquitous. Particularly the use of laptops as instruments is a thriving practice in many genres and subcultures. The opportunity to command the most intricate level of control on the smallest of time scales in music composition and computer graphics introduces a number of complexities and dilemmas for the performer working with algorithms. Writing computer code to create audiovisuals offers abundant opportunities for discovering new ways of expression in live performance while simultaneously introducing challenges and presenting the user with difficult choices. There are a host of computational strategies that can be employed in live situations to assist the performer, including artificially intelligent performance agents who operate according to predefined algorithmic rules. This thesis describes four software systems for real time multimodal improvisation and composition in which a number of computational strategies for audiovisual laptop performances is explored and which were used in creation of a portfolio of accompanying audiovisual compositions.

Opinion analysis is an area of research which deals with the computational treatment of opinion statement and subjectivity in textual data. Opinion analysis has emerged over the past couple of decades as an active area of research, as it provides solutions to the issues raised by information overload. The problem of information overload has emerged with the advancements in communication technologies which gave rise to an exponential growth in user generated subjective data available online. Opinion analysis has a rich set of applications which are used to enable opportunities for organisations such as tracking user opinions about products, social issues in communities through to engagement in political participation etc. The opinion analysis area shows hyperactivity in recent years and research at different levels of granularity has, and is being undertaken. However it is observed that there are limitations in the state-of-the-art, especially as dealing with the level of granularities on their own does not solve current research issues. Therefore a novel sentence level opinion analysis approach utilising clause and phrase level analysis is proposed. This approach uses linguistic and syntactic analysis of sentences to understand the interdependence of words within sentences, and further uses rule based analysis for phrase level analysis to calculate the opinion at each hierarchical structure of a sentence. The proposed opinion analysis approach requires lexical and contextual resources for implementation. In the context of this Thesis the approach is further presented as part of an extended unifying framework for opinion analysis resulting in the design and construction of a novel corpus. The above contributions to the field (approach, framework and corpus) are evaluated within the Thesis and are found to make improvements on existing limitations in the field, particularly with regards to opinion analysis automation. Further work is required in integrating a mechanism for greater word sense disambiguation and in lexical resource development.

The existing authorisation systems within the context of Web Services mainly apply two access control approaches – Role-Based Access Control (RBAC) and Attribute-Based Access Control (ABAC). The RBAC approach links an authenticated Web Service Requester to its specific access control permission through roles, but RBAC is not flexible enough to cater for some cases where extra attribute information is needed in addition to the identity. By contrast, the ABAC approach has more flexibility, as it allows a Web Service Requester to submit necessary credentials containing extra attribute information that can fulfil the policies declared by a Web Service Provider, which aims to protect the sensitive resources/services. RBAC and ABAC can only help to establish a unilateral trust relationship between two Web Services to enable a Web Service Provider to make an access control decision. Unfortunately, the nature of Web Services presents a high probability that two Web Services may not know each other. Therefore, successful authorisation may fail, if the Web Service Requester does not trust the Web Service Provider. Trust Negotiation (TN) is also an access control approach, which can provide a bilateral trust relationship between two unknown entities, so it sometimes can enable authorisation success in situations where success is not possible through RBAC or ABAC approaches. However, interoperability issues will arise between authorisation systems within Web Services, where a bilateral trust-based authorisation solution is applied. In addition, a lack of a unified approach that can address the interoperability issues remains as a research problem. This research aims to explore possible factors causing the lack of interoperability first, and then to explore an approach that can address the interoperability issues. The main contributions of this research are an improved interoperability model illustrating interoperability issues at different layers of abstraction, and a novel interoperability-solution design along with an improved TN protocol as an example of utilising this design to provide interoperability between authorisation systems within Web Services.

From jazz clubs to cheese plates, the term curation has become a signifier of the growing need to organise and prioritise the seemingly endless possibilities of the digital sphere. The issue addressed here is in the associated meanings of the word curation and what it means to be a curator by examining the experience of the curatorial within a discrete context: the Irish curatorial landscape. The word curation comes from the Latin curare, to care for, and has long been associated with the professional duties of those selected as custodians for objects and knowledge deemed to be important to communities, nations, countries or even the world. However, as objects move from being purely physical to the digital, and knowledge changes from being transmitted through similarly physical media to digital formats that can be set free on the Web, what it means to curate has also changed. Curators are no longer necessarily identified as employed within museums or galleries; the word is now also applied to those who engage with and aid in the management and presentation of digital assets online. Curators have emerged in the online space much like their forerunners, bloggers or citizen journalists. We are now seeing the rise of citizen curators on the Web, which has not created these individually motivated curators, but has made their curatorial activities visible. Citizen journalists no longer need to have a printing press or publishing house to communicate with their audience; similarly, citizen curators do not need a private cabinet of curiosities or a job in a museum to allow them to curate or exhibit to an audience. The aims of this research are threefold: to examine the current terminology related to curation by those who identify as curators or engage in curation in Ireland; to define what it means to be a curator or a citizen curator within the Irish context; and to investigate the changing nature of exhibition spaces contained in the Irish context in light of the Web and digital spaces. The study will take the form of an autoethnography, exploiting my unique position within the museum and open knowledge community in Ireland to examine current understandings of curation and the phenomenon of the citizen curator. The focus will be on my work within Wikimedia Community Ireland (WCI), a branch of the Wikimedia Foundation which promotes the use of Wikipedia in Ireland in education, culture, and open knowledge. As an autoethnographer, I can act as an intermediary, part way between those working in cultural organisations and the public involved in knowledge building projects. The study will look at how those engaged in curation articulate the work they do by means of interviews and participant observation. These sources will allow for the development of a spectrum of curatorial practice. The spectrum will arise from the participants’ (both citizen curators and those working in Irish cultural institutions) own understanding and definitions of curation and what it means to curate. In placing these definitions of curation within a spectrum that takes in broader understandings of curatorial practice, the newer forms of digital curation, and a picture of how the citizen curator relates to these methods, will emerge. The disruptive effect which the digital, and in particular the concept of the Long Tail, has brought to bear upon understanding of the assembling, storing, and using of collections will be examined. It will answer many of the issues surrounding the discipline-specific definitions of curation and the curator while informing their relationship with each other. By drawing out curation into a spectrum, what unfolds is the movement of curation from a traditional and closed system of learnt practices, to one which is formed around more open and accessible conventions of curation. In identifying the citizen curator, their role in the larger curatorial debate can be acknowledged and better incorporated into the multitude of online curated projects. This hinges on the emergence of the Do It With Others ethos which pervades both online and offline creative communities, and it redefines curation from a solitary practice, to one which is demarcated by its participatory nature.

An observation of the evolution of the marketing messages of Telecommunications Company Vodafone between 2007 and 2013 sheds light on the significant changes that occurred in the communications arena throughout this period. The shift is not a hypothetical one; it is real and reflected in the shifting usage profiles of millions of mobile users. Moreover the shift is not limited to the changes in the technology which enables mediated conversation. Reference is made to existing literature to define the activity under study, understand the historical context of conversation, both in the mobile and online space, measure the present shifts and explore how findings can contribute to a better understanding of the future. In the context of the existing body of work and the significant changes that occurred over the past years, the research aims to propose a new model of conversation in response to the chosen research question, which asks, “how is conversation evolving as a result of take up of new media in Malta?“ A two‐step approach is adopted. The first research stream makes use of a data set of usage logs of a sample of smartphone adopters on the Vodafone network. A comparison of the usage logs before and after adoption is used to shed light on the influence of the device on the users’ conversations. The analysis is supported with two secondary experiments, one relating to the usage of mobile Internet on specific days during the year and the other extending the experiment to everyday conversation on Facebook. The second research stream consists of a review of the new media landscape with a specific focus on key themes. The findings are used to corroborate a model of shifting conversation. The model proposes that conversation is captured in three dimensions - a shift from synchronous to asynchronous conversation, from private to public and from transient to persistent exchanges.

A rapidly emerging need within virtual environments is the ability to accommodate a large, distributed user-base. In particular, Internet-based distributed virtual environments represent a challenge in providing a heterogeneous environment accessible by many thousands of users. Interest Management represents the process of filtering network data based on relevance to users, in order to make the most efficient use possible of available network capacity. In this thesis, the potential for a visual-attention based refinement to interest management is explored, which utilises a spotlight-based model of human attention. By considering the relationship between attention and interest management, this thesis illustrates a tendency within existing systems to use a simplistic or object-based approach to measure relevance, typically based on proximity to the user or visibility. By considering the current state of the art alongside common theories of visual attention, it is hypothesised that a refinement aiming to accommodate a spotlight model may offer an approach capable of more efficient use of bandwidth when compared to existing techniques. In particular, it is suggested a spotlight model would be capable of accommodating key aspects of human visual attention in a processor-efficient and composable manner. Bandwidth conserved by the use of such an approach may be subsequently re-utilised to provide a higher degree of interactivity within a distributed virtual environment, or to support greater numbers of simultaneous users. In order to evaluate the effectiveness of a spotlight-based approach, a test environment is created which allows users to participate in a number of activities alongside a large volume of simulated clients. Throughout these activities, interest management is changed seamlessly between variations of a spotlight approach, extremes, and an approximation of the current state of the art. Results obtained from a total of 15 users indicate a preference for such an approach when compared to the current state of the art in 80% of subjects, and suggest the capacity to reduce available bandwidth by up to 60%, dependent on task, without perceivable impact.

As individuals the ideal learning scenario would be a learning environment tailored just for how we like to learn, personalised to our requirements. This has previously been almost inconceivable given the complexities of learning, the constraints within the environments in which we teach, and the need for global repositories of knowledge to facilitate this process. Whilst it is still not necessarily achievable in its full sense this research project represents a path towards this ideal. In this thesis, findings from research into the development of a model (the Adaptive Intelligent Personalised Learning (AIPL)), the creation of a prototype implementation of a system designed around this model (the AIPL environment) and the construction of a suite of intelligent algorithms (Personalised Adaptive Filtering System (PAFS)) for personalised learning are presented and evaluated. A mixed methods approach is used in the evaluation of the AIPL environment. The AIPL model is built on the premise of an ideal system being one which does not just consider the individual but also considers groupings of likeminded individuals and their power to influence learner choice. The results show that: (1) There is a positive correlation for using group-learning-paradigms. (2) Using personalisation as a learning aid can help to facilitate individual learning and encourage learning on-line. (3) Using learning styles as a way of identifying and categorising the individuals can improve their on-line learning experience. (4) Using Adaptive Information Retrieval techniques linked to group-learning-paradigms can reduce and improve the problem of mis-matching. A number of approaches for further work to extend and expand upon the work presented are highlighted at the end of the Thesis.