Constructive interval temporal logic in Alf

This paper gives an implementation of an interval temporal logic in a constructive type theory, using the Alf proof system. After explaining the constructive approach, its relevance to interval temporal logic and potential applications of our work, we explain the fundamentals of the Alf system. We then present the implementation of the logic and give a number of examples of its use. We conclude by exploring how the work can be extended in the future

Are subsets necessary in Martin-Lof type theory?

After introducing Martin-Lof's type theory, the paper introduces the rules proposed by various authors for adding subset types to the system, and the justification given for their addition. These justifications are examined, and it is argued that by a combination of lazy evaluation and transformation using the Axiom of Choice that subsets need not be added to the system to make it usable

Art meets science – empowering stroke patients to regain muscular control through creative graphics technology, psycho-physiology and neuroplasticity.

Treating patients with a cerebrovascular accident or stroke is complicated by severity and site of brain lesion. Muscular control is lost when neural pathways are interrupted or damaged due to embolus, thrombosis or ruptured aneurysm. Return of movement is further hindered by sustained spasticity of muscle groups or inflammation or severance to functionally important neural pathways. Neuro-feedback mechanisms have been explored in the past with some success. A new, improved and innovative method is presented that makes use of psycho-physiology techniques providing immediate visual, auditory and neurological feedback via a fast switching device that relays neuro-muscular movement during rehabilitative tasks and exercises. Visual and auditory signals enable the patient to make use of neurological activity in a purposeful manner, re-directing it to particular tasks. Concentrating on a series of tones elicited via a computer console and by vigilance of changing visual graphics displays allows the patient to accurately control unwanted activity and enables the body to re-learn previously damaged neural circuits. Patients gaining the ability to re-direct and re-route neural pathways have made significant gains in returning function to their leg muscles, particularly to the quadriceps group. These are very often the first groups of muscles to be affected during stroke and make the patient wheelchairbound and often permanently disabled. Occupational and social functioning is affected and quality of life is altered. Patients who are able to re-gain posture and re-learn to walk are empowered and have a better chance of returning to social and occupational settings. Trials in the United Kingdom have shown significant benefits for patients using neuro-feedback. Significant success by these patients has provided researchers with the potential benefits of using neuro-feedback in rehabilitation and increases our scientific and clinical knowledge of neuro-plasticity in even the large muscle groups of the damaged human body. This technology bridges creative artistic graphics technology with thorough evidencebased science

em Where do I begin? A problem solving approach to teaching functional programming

This paper introduces a problem solving method for teaching functional programming, based on Polya's `How To Solve It', an introductory investigation of mathematical method. We first present the language independent version, and then show in particular how it applies to the development of programs in Haskell. The method is illustrated by a sequence of examples and a larger case study

Higher-order + Polymorphic = Reusable

This paper explores how certain ideas in object oriented languages have their correspondents in functional languages. In particular we look at the analogue of the iterators of the C++ standard template library. We also give an example of the use of constructor classes which feature in Haskell 1.3 and Gofer

A Case Study in Refactoring Functional Programs

Refactoring is the process of redesigning existing code without changing its functionality. Refactoring has recently come to prominence in the OO community. In this paper we explore the prospects for refactoring functional programs. Our paper centres on the case study of refactoring a 400 line Haskell program written by one of our students. The case study illustrates the type and variety of program manipulations involved in refactoring. Similarly to other program transformations, refactorings are based on program equivalences, and thus ultimately on language semantics. In the context of functional languages, refactorings can be based on existing theory and program analyses. However, the use of program transformations for program restructuring emphasises a different kind of transformation from the more traditional derivation or optimisation: characteristically, they often require wholesale changes to a collection of modules, and although they are best controlled by programmers, their application may require nontrivial semantic analyses. The paper also explores the background to refactoring, provides a taxonomy for describing refactorings and draws some conclusions about refactoring for functional programs

A revision of Calyptochloa C.E.Hubb. (Poaceae), with two new species and a new subspecies

Thompson, E.J. & Simon, B.K. (2012). A revision of Calyptochloa C.E.Hubb. (Poaceae), with two new species and a new subspecies. Austrobaileya 8(4): 634–652. Two new species of Calyptochloa C.E.Hubb. (Calyptochloa cylindrosperma E.J.Thomps. & B.K.Simon and C. johnsoniana E.J.Thomps. & B.K.Simon) endemic to central Queensland, and a new subspecies of Calyptochloa gracillima C.E.Hubb. (C. gracillima subsp. ipsviciensis E.J.Thomps. & B.K.Simon) endemic to southeast Queensland are described and illustrated

A Tableau Method for Interval Temporal Logic

In this paper we present a complete tableau method for interval temporal logic including the projection operator. Central to our strategy is the identification of normal forms for all the operators of our logic. In effect, these normal forms give inductive definitions of the ITL operators. Then, in the style of Wolper, we define a tableau decision procedure to check satisfiability of our logic. For simplicity of presentation we work in the propositional setting