An Object-Z formal speci cation 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 speci cation that can be readily...

RELATIONSHIPS Relationships are critical to object modelling. It is generally agreed that associations (of several °avours), generalizations and aggregations are useful, although the exact semantics di®er between authors. It is important that we, the object-oriented community, gain a common understanding and, in that context, recent formalisms have helped to clarify the situation: the OMG-inspi...

The object of the present paper is to study Z-symmetric manifold with projective curvature tensor. At first, we case Z-tensor and Ricci tensor being Codazzi type. Next, consider recurrent We also divergence-free Z-tensor. Finally, construct an example

Research into the industrial application of formal methods has concentrated almost exclusively on the speci cation of software systems in highrisk or safety critical applications|thus, attention has been directed to technical problems with technical systems. The Formal Methods Research Group at Curtin University has, however, been addressing the potential practical application of Z and Object-Z...

Morgan’s refinement calculus (MRC) is one of the well-known methods allowing the formality presented in the program specification to be continued all the way to code. On the other hand, Object-Z (OZ) is an extension of Z adding support for classes and objects. There are a number of methods for obtaining code from OZ specifications that can be categorized into refinement and animation methods. A...

Many researches to testing object-oriented programs (OOPs) have been proposed for the past decade. However, most of these researches have centered only around the class-level testing instead of the whole profiles of OOP development. This paper presents a framework to test OOPs from em formal specification to em test data generation. The formal specification of object-oriented program is specifi...

Morgan’s refinement calculus (MRC) is one of the well-known methods allowing the formality presented in the program specification to be continued all the way to code. On the other hand, Object-Z (OZ) is an extension of Z adding support for classes and objects. There are a number of methods for obtaining code from OZ specifications that can be categorized into refinement and animation methods. A...

Web technologies based on XML, e.g. Semantic Web and Web Services, facilitate Web automation and universally accessible content. One of the key factors for the success of XML-based technologies is of finding an efficient query evaluation algorithm for XMLbased data models. An XML twig query is a complex selection predicate on both structure and content of a labelled XML document. Several novel ...

Problem 1.(The Mapping Cone is a Homotopy Limit and a Homotopy Colimit) Let A be an Abelian category. Let A● and B● be objects in Ch●(A). Let f ● ∶ A● → B● be a morphism in Ch●(A). For every object T ● of Ch●(A), a left homotopy annihilator to T ● is a pair (Q●, σ●) of a morphism Q● ∶ B● → T ● in Ch●(A) and a nullhomotopy (σn ∶ An → T n−1)n∈Z of Q● ○ f ●, i.e., for every n ∈ Z, Q ○ f = dn−1 T ○...

Magnetic resonance electrical impedance tomography (MREIT) attempts to provide conductivity images of an electrically conducting object with a high spatial resolution. When we inject current into the object, it produces internal distributions of current density and magnetic flux density. By using a magnetic resonance imaging (MRI) scanner, we can measure B(z) data where z is the direction of th...