In this paper we discuss how the speciication of components may be separated from the description of the context in which they are used. There are a number of ways in which this might be possible and here we show how to use the technique of promotion in Object-Z to combine components which are speciied using process algebras. We discuss two approaches, the rst is to separate out the speciica-ti...

The possibilities to run with a linear collider at the Z-pole with high luminosity are examined. Apart from the implications on machine and detector the interest for electroweak and B-physics is discussed. Plenary talk at the International Workshop on Linear Colliders, Fermilab 24 28 October 2000

This paper presents a method of reasoning about Object-Z speciications. The approach utilises the modularity inherent in Object-Z speciications to simplify proofs. Properties proved for a class in isolation can be used when that class is either inherited by another class or instantiated as part of a system of interacting objects. Proofs using structural induction and the notion of object integr...

VM/Pass-Through, an interactive networking facility, has gained widespread acceptance within ISM and with ISM customers. Pass-Through allows a single terminal access to many different computers, including those at distant locations. In building Pass-Through, and in observing its growing use, we have had an opportunity to study the practical implications of this facility and of our approach to i...

The main purpose of this report is to introduce a formal speciication notation ZedCharts and its applications. The ZedCharts notation is a combination of a Statecharts subset and the Z notation. This notation can be used for specifying reactive systems and safety-critical systems by describing their behaviour and functionality formally. We will also demonstrate an eeective approach to using Zed...

Since the seminal work of the Gestalt psychologists, there has been great interest in understanding what factors determine the perceptual organization of images. While the Gestaltists demonstrated the significance of grouping cues such as similarity, proximity and good continuation, it has not been well understood whether their catalog of grouping cues is complete--in part due to the paucity of...

The notion of a Γ-symmetric space is a generalization of the classical notion of a symmetric space, where a general finite abelian group Γ replaces the group Z 2. The case Γ = Z k has also been studied, from the algebraic point of view by V.Kac [10] and from the point of view of the differential geometry by Ledger, Obata [12], Kowalski [11] or Wolf-Gray [18] in terms of k-symmetric spaces. In t...

We consider Z{matrices and inverse Z{matrices, i.e. those nonsingular matrices, whose inverse is a Z{matrix. Recently Fiedler and Markham introduced a classii-cation of Z{matrices. This classiication directly leads to a classiication of inverse Z{matrices. Among all classes of Z{matrices and inverse Z{matrices the classes of M{matrices, N 0 {matrices, F 0 {matrices and inverse M{matrices, inver...

The sarcomeric Z-disc defines the lateral borders of the sarcomere and has primarily been seen as a structure important for mechanical stability. This view has changed dramatically within the last one or two decades. A multitude of novel Z-disc proteins and their interacting partners have been identified, which has led to the identification of additional functions and which have now been assign...