Information Flow for ALGOL-like Languages

In this paper we present an approach to information flow analysis for a family of languages. We start with a simple imperative language. We present an information flow analysis using a flow logic. The paper contains detailed correctness proofs for this analysis. We next extend the analysis to a restricted form of Idealised Algol, a call-by-value higher-order extension of the simple imperative language (the key restriction being the lack of recursion). The paper concludes with a discussion of further extensions, including a probabilistic extension of Idealised Algol.

Extending Agent Languages for Autonomy

BDI agent languages provide a useful abstraction for complex systems comprised of interactive autonomous entities, but they have been used mostly in the context of single agents with a static plan library of behaviours invoked reactively. These languages provide a theoretically sound basis for agent design but are very limited in providing direct support for autonomy and societal cooperation needed for large scale systems. Some techniques for autonomy and cooperation have been explored in the past in ad hoc implementations, but not incorporated in any agent language. In order to address these shortcomings we extend the well known AgentSpeak(L) BDI agent language to include behaviour generation through planning, declarative goals and motivated goal adoption. We also develop a language-specific multiagent cooperation scheme and, to address potential problems arising from autonomy in a multiagent system, we extend our agents with a mechanism for norm processing leveraging existing theoretical work. These extensions allow for greater autonomy in the resulting systems, enabling them to synthesise new behaviours at runtime and to cooperate in non-scripted patterns.

Language processing and acquisition in languages of Semitic, root-based, morphology / Joseph Shimron

This book addresses a fundamental question in the morphological analysis and representation of Semitic languages—namely, whether Semitic word morphology is root based or word based. As Shimron suggests, “there are reasons to view the templates, not the roots, as the more influential factor in determining Semitic morphology” (p. 5). Yet, as others would argue, there are reasons not to disregard the root-based hypothesis altogether. In the case of Arabic morphology, for example, verbal forms inherently contain three nonlinear levels: the consonantal root, the vowel pattern, and the templatic prosody. This nonlinear feature provided a perfect illustration of what has become termed in the literature as root-and-patterns morphology (McCarthy & Prince, 1986, 1990).

Development of DAL and DAPL languages for building distributed applications

A common characteristic among parallel/distributed programming languages is that the one language is used to specify not only the overall organisation of the distributed application, but also the functionality of the application. That is, the connectivity and functionality of processes are specified within a single program. Connectivity and functionality are independent aspects of a distributed application. This thesis shows that these two aspects can be specified separately, therefore allowing application designers to freely concentrate on either aspect in a modular fashion. Two new programming languages have been developed for specifying each aspect. These languages are for loosely coupled distributed applications based on message passing, and have been designed to simplify distributed programming by completely removing all low level interprocess communication. A suite of languages and tools has been designed and developed. It includes the two new languages, parsers, a compilation system to generate intermediate C code that is compiled to binary object modules, a run-time system to create, manage and terminate several distributed applications, and a shell to communicate with the run-tune system. DAL (Distributed Application Language) and DAPL (Distributed Application Process Language) are the new programming languages for the specification and development of process oriented, asynchronous message passing, distributed applications. These two languages have been designed and developed as part of this doctorate in order to specify such distributed applications that execute on a cluster of computers. Both languages are used to specify orthogonal components of an application, on the one hand the organisation of processes that constitute an application, and on the other the interface and functionality of each process. Consequently, these components can be created in a modular fashion, individually and concurrently. The DAL language is used to specify not only the connectivity of all processes within an application, but also a cluster of computers for which the application executes. Furthermore, sub-clusters can be specified for individual processes of an application to constrain a process to a particular group of computers. The second language, DAPL, is used to specify the interface, functionality and data structures of application processes. In addition to these languages, a DAL parser, a DAPL parser, and a compilation system have been designed and developed (in this project). This compilation system takes DAL and DAPL programs to generate object modules based on machine code, one module for each application process. These object modules are used by the Distributed Application System (DAS) to instantiate and manage distributed applications. The DAS system is another new component of this project. The purpose of the DAS system is to create, manage, and terminate many distributed applications of similar and different configurations. The creation procedure incorporates the automatic allocation of processes to remote machines. Application management includes several operations such as deletion, addition, replacement, and movement of processes, and also detection and reaction to faults such as a processor crash. A DAS operator communicates with the DAS system via a textual shell called DASH (Distributed Application SHell). This suite of languages and tools allowed distributed applications of varying connectivity and functionality to be specified quickly and simply at a high level of abstraction. DAL and DAPL programs of several processes may require a few dozen lines to specify as compared to several hundred lines of equivalent C code that is generated by the compilation system. Furthermore, the DAL and DAPL compilation system is successful at generating binary object modules, and the DAS system succeeds in instantiating and managing several distributed applications on a cluster.

Historical landscape languages : creating symbolic space over generations

Landscape creation takes time, patience, water, and languages of visions. Landscape ‘history’ is not short in time but progressive, evolutionary and slow. In the case of the Adelaide Park Lands, the spectre of the myth of the Park Lands as a historical statement is very evident in planning and design discourses in South Australia. It is a mental creation of a number of actors who sought initially to remove all vegetation and evidence of human sedentary occupation. These actors applied languages to argue for a certain type of landscape as well as for the human, water, plant and financial resources to construct this picture. Some were simple letters to editors, some were political statements and pronouncements, some were the actual endeavours and expressions of municipal officials and city gardeners who sought to plant and craft representations of what they thought were ideal visions, and some were consultants who equally sought to apply their ideals.

This paper considers the historiography of the Adelaide Park Lands through the languages of those who argued for and enabled its planting using their words, languages and action examples.

Community languages, linguistic isolation and social exclusion in the Australian context

The detrimental impacts of social exclusion to health and well-being are well-known and are of increasing concern around the world. For many of the population sub-groups who are most at risk of social exclusion, linguistic isolation—the inability to use and understand the majority language—is a major barrier to full participation in the life of the community as well as to full integration into the society in which its members live. This paper, using data obtained from community-based research in Melbourne, Australia, will discuss the problem of linguistic isolation in the context of Australian multicultural policy and use of languages other than English among members of culturally and linguistically diverse (CALD) communities. The experience of members of two specific CALD communities, speakers of Arabic and speakers of Indonesian, will be discussed to illustrate the impacts of linguistic isolation on health and well-being and to elucidate the relationship between CALD status and social exclusion in these communities.