The main research question, which has been the basis for this thesis is “How should system verification and validation be conducted for large software systems to achieve high quality at a low cost?” Since system verification and validation activities involve a great number of processes and techniques, the research must be limited. The important issues for the organization have influenced the li...

What is an algorithm? The interest in this foundational problem is not only theoretical; applications include specification, validation and verification of software and hardware systems. We describe the quest to understand and define the notion of algorithm. We start with the Church-Turing thesis and contrast Church’s and Turing’s approaches, and we finish with some recent investigations.

UML is known as one of the most common methods in software engineering. Since this language is semi-formal, many researches and efforts have been performed to transform this language into formal methods including Petri nets. Thus, the operation of verification and validation of the qualitative and nonfunctional parameters could be achieved with more ability. Since the majority of the real world...

UML is known as one of the most common methods in software engineering. Since this language is semi-formal, many researches and efforts have been performed to transform this language into formal methods including Petri nets. Thus, the operation of verification and validation of the qualitative and nonfunctional parameters could be achieved with more ability. Since the majority of the real world...

The focus of the Spatial Verification Intercomparison Project (ICP) is meta-verification, that is, learning about the verification methods themselves. For a verification method to be useful it must inform the user on the nature of the forecast errors. The "fake data" component of the ICP attempts to evaluate how well the verification methods provide information on known applied errors in real a...

This paper introduces a unified approach t o the problem of verifying Alignment hypotheses in the presence of substantial amounts of uncertainty in the predicted locations of projected model features. Our approach is independent of whether the uncertainty as distributed or bounded, and, moreover, incorporates information about the domain in a formally correct manner. Izformation which can be in...

For the specification of object-oriented systems, usually several models representing different views are developed. The necessary integration of views is often delayed until implementation, but for validation and verification purposes the merging of views is desirable already during specification. Motivated by this, a model of objects is proposed in which the different views on an object are r...

W e propose an on-line writer verification method to improve the reliability of verifying a specific system user. In the proposed method, a different text including ordina y characters is used on eve y verification process. This text can be selected automatically by the verification system so as to reflect the specific writer's fentures. A specific writer is accepted only when the same text, wh...

This paper addresses the issue of selective disclosure of verifiable content. It extends previous work relating to Content Extraction Signatures [21] to implement a more complex structure that encodes a richer, more flexible fragment extraction policy, which includes fragment grouping. The new extraction policy enables the signer to specify both optional and mandatory fragment associations (or ...

There is significant interest in the use of Z in conjunction with object-orientation. Here we present a new approach to structuring Z specifications in an object-oriented (OO) style. Our structuring is based on views, it uses the schema calculus, and it does not extend Z. The resulting OO Z specifications are comprehensible, modular, and conceptually clear. The modularity of the new approach su...