We present a deep H-band image of the field of a candidate z=10 galaxy magnified by the foreground (z=0.25) cluster Abell 1835. The image was obtained with NIRI on Gemini North to better constrain the photometry and investigate the morphology of the source. The image is approximately one magnitude deeper and has better spatial resolution (seeing was 0.4-0.5 arcsec) than the existing H-band imag...

We use a combination of three techniques for the speciication of processes, data and time: CSP, Object-Z and Duration Calculus. Whereas the combination of CSP and Object-Z is well established by the work of C. Fischer 2, 3], the integration with Duration Calculus is new. The combination is used to specify parts of a novel case study on radio controlled railway crossings.

We use a combination of three techniques for the specification of processes, data and time: CSP, Object-Z and Duration Calculus. Whereas the combination of CSP and Object-Z is well established by the work of C. Fischer [2, 3], the integration with Duration Calculus is new. The combination is used to specify parts of a novel case study on radio controlled railway crossings.

This paper presents a verification approach for multi agent systems. The specification is based upon Object-Z and uses the influence/reaction model. The verification process consists in the transformation of Object-Z specifications into transition systems. This allows us to verify automatically some properties of the specification such as history invariants expressed by temporal logic formulas.

An Object-Z formal speciication of the ODP Trader is presented which concisely captures the hierarchical context structure, the distribution of information and the communication aspects of the Trader. Particular use is made of generic classes, class inheritance and object aggregation (i.e. the instantiation of collections of similar objects) to give a structured speciication that can be readily...

An Object-Z formal speciication of the ODP Trader is presented which concisely captures the hierarchical context structure, the distribution of information and the communication aspects of the Trader. Particular use is made of generic classes, class inheritance and object aggregation (i.e. the instantiation of collections of similar objects) to give a structured speciication that can be readily...

Focusing on object-oriented designs, this paper proposes a mapping for translating systems modelled in the Unified Modelling Language (UML) incorporating Object Constraint Language (OCL) constraints into formal software specifications in Object-Z. Joint treatment of semi-formal model constructs and constraints within a single translation framework and conversion tool is novel, and leads to the ...

This paper describes the formal specification of object types for managing inter-media synchronisation and control within PREMO, an emerging ISO/IEC standard for multimedia systems. Object-Z, an object-oriented extension to the Z specification language, is used for this purpose. Some aspects of PREMO are non-trivial to express in Object-Z, and the paper outlines the reasons for choosing this sp...