Defining Relationships in Ecology Using Object-Oriented Formal Specifications

A formal object-oriented specification using Object-Z is given of an animal's environment which builds on previous work using formal descriptions in this area. The object framework provides a closer match between natural categories and specified classes, and the formal specification acts as a tool to explicitly state all assumptions, consequences and behaviors involved for a set of objects at hand. The object-oriented specification can then be used as a basis for building a corresponding software system using an object-oriented language. 1 INTRODUCTION The formal specification languages being developed in computer science attempt to abstract essential properties of systems without getting bogged down in `implementation' or inessential details. Although primarily developed for the specification of software, these languages can be used for describing nonsoftware systems. They can provide the `glue' between the rarified world of mathematical theorizing and the nuts-and-bolts of implement..

An Abstract Object Model of an Animal's Environment

A formal object-oriented specification using Object-Z is given of part of an animal's environment. The object framework provides a closer match between natural categories and specified classes, and the formal specification acts as a tool to explicitly state all assumptions, consequences and behaviors involved for a set of objects at hand. Key words: Object-orientation; Formal specification 1 Introduction The formal specification languages being developed in computer science attempt to abstract essential properties of systems without getting bogged down in `implementation' or inessential details. Although primarily developed for the specification of software, these languages can be used for describing non-software systems. They can provide the `glue' between the rarified world of mathematical theorizing and the nuts-and-bolts of implemented code. With the aid of theorem provers one can prove properties of abstract specifications just as in mathematics, and with the aid of refinement me..

Complex Object Models Of Natural Systems

An object modelling language is described which is suitable for representing complex objects and their interrelationships. It's pedigree comes from a number of established object-oriented analysis & design notations and formal specification languages. However, it extends the type of model components to include classes, aggregations, roles, classifications, class unions, features and assertions. The types of relationships between objects also include associations and inheritance. We indicate the utility of this notation in showing part of an object model of a large tidal flat ecosystem model. INTRODUCTION Natural systems can be extremely complex both in terms of the number of components and the number of interactions involved. In order to understand these interrelationships, a (data) modelling technique which has a reasonable graphical representation is very useful. But the modelling system should also have a good semantic foundation so that models have a clear meaning. The object-ori..

Object-Oriented Formal Specification for Spatial Representation: A Terrain Model its Channel Network

A formal object-oriented specification using Object-Z is given of a digital terrain model and some of its associated geomorphometry. The object framework provides a closer match between natural categories and specified classes, and the formal specification acts as a tool to explicitly state all assumptions, consequences and behaviors involved for a set of objects at hand. The object-oriented specification can then be used as a basis for building a corresponding software system using an object-oriented language. 1 INTRODUCTION Digital terrain models (DTMs) are an important way of representing landscape in geographical information systems. One important class of these models are the triangulated irregular networks (TINs). Given such a landscape model, one often needs to delineate various drainage features of the landscape such as channel networks, ridges, basins and plateaus. A specification using the object-oriented formal specification language Object-Z is given of a landscape modelle..

Formal Ontologies, Specifications and Logics in Canopy Research

A number of description techniques are outlined and their usefulness in describing the domain of canopy research and associated data models is indicated. The approaches considered are: formal ontologies, object-oriented formal specifications, domain-specific logics and domain languages. We consider a simple abstraction of tree architecture to illustrate some of the concepts, especially those of formal specifications. Keywords: canopy, tree architecture, formal ontology, object-orientation, formal specification, logics, domain languages. 1 Introduction Canopy research is characterized by a wide variety of disciplines and perspectives, and of spatial and temporal scales (Nadkarni & Parker, 1994). To assist this multidisplinary effort in collaboratively exploring the canopy there is benefit in expending effort in developing common ontologies and data models. This paper provides an overview of these and related fields and indicates their relevance to canopy research (see Figure 1). We c..

The Evolution of Sporting Strategies

. This paper describes C oac H, an evolutionary simulator developed to investigate strategies for teams in a competitive environment, and discusses some of the issues surrounding the evolution of cooperation among team members. As its title suggests, C oac H is a simulator of sporting environments, as these possess the required motivations for such behaviour and have the potential to benefit the real sporting world. In addition to describing C oac H, this paper describes two applications illustrating the potential and value of the system. It examines cooperation within a simplified model of the game of volleyball in which cooperation emerged in the form of players passing the ball between them in order to control it for an effective offensive hit. Each player learnt a specialized skill which, in close harmony with the other team member's skills, provided the team with a strategy not unlike those used by real volleyball players. Some preliminary experiments were also carried out to in..

Specifying The Just-In-Time Kanban System Using Two Object-Oriented Modelling Techniques

Modelling by means of specification languages is increasingly being recognised as an important phase in system development. It encourages one to think about problems using models organised around real-world situations. The system to be developed should then be consistent, correct and unambiguous with respect to the models produced. The JustIn -Time kanban system is an example of a real-world problem with a multiple-supplier and multiple-client architecture. The purpose of this paper is to use two specification languages proposed in the literature to model the kanban system. The languages used are LOOPN (Lakos 1991) and Object-Z (Duke, King, Rose, and Smith 1991a). The case study focuses on describing the kanban system in the different notations, and thus investigating how well they can express the JustIn -Time system. The kanban system consists of many replicated components, each having the same state space and exhibiting the same behaviour. To describe each and every component in the ..

MON: An Object Relationship Model Incorporating Roles, Classification, Publicity and Assertions

This paper describes the current status of an object modelling notation that incorporates expressive, orthogonal assertions and different categories of relationships between objects. The trichotomy of assertions (preconditions, postconditions and invariants) are now applicable to almost all system components. This paper describes examples of using assertions on relationships and classes. The notation, called Monash Object Notation (MON), can be used to specify systems at differing levels of detail and provides the expressive power to specify temporal, creation, destruction and persistency constraints. 1 Introduction Object-oriented programming is essentially programming by abstraction. An object-oriented programmer aims to build solutions to problems by building reusable abstract data types. Current object-oriented modelling notations such as the Object Modelling Technique (OMT) (Rumbaugh, Blaha, Premerlani, and Lorensen 1991) and the Business Object Model (BON) (Nerson 1992), attempt..

Simulated Annealing of Two-Dimensional Plant Canopies

Introduction The spatial arrangement of leaves in a plant canopy is governed by a number of factors such as radiative and diffusive couplings and architectural support. Concentrating on how the plant's canopy structure affects its carbon balance through its efficacy in trapping radiation, the aim of this research is to investigate nearoptimal arrangements of leaves using an optimizing simulation technique. A Monte Carlo simulation method called simulated annealing is being developed to perform the optimization. Leaves are modelled as line segments which join points on a regular two-dimensional lattice. A net carbon balance is computed for a given configuration of leaves as the sun transcends a number of sky sectors. To improve a given leaf configuration, a Poster presented at ESA95 -- Ecological Society of Australia Open Forum & Symposium, Hobart, 1995. small change is made to it which is then considered to be an improvement based on