Analysis and verification of an automatic document feeder

Modern copying machines are versatile and complex systems in which embedded software plays an essential role. The progress towards faster and more stable machines that can satisfy ever growing customers' needs, places strict requirements on the efficiency and quality of such software. In order to meet these requirements, the software should be well-designed and free of errors. Using modern formal verification techniques, software designs can be checked for errors and deadlocks so that their quality can be assessed and improved at an early stage of the development process. In this paper, we analyze the embedded software of an Automatic Document Feeder (ADF). ADFs are important components of copier machines. The ADF studied here is a prototype developed by Océ-Technologies B.V., a company that develops professional printing systems. We construct a model of the ADF in µcrl, a process algebra-based specification language, and express the system's requirements in the modal µ-calculus. Next, we use the µcrl and Cadp tool sets to check whether the system meets its requirements. This analysis reveals important errors in the ADF and we propose solutions to these problems. Also, we show that some requirements that engineers assumed to be valid, are too strict. We present slightly weaker versions of these requirements and show that these do hold. In this sense, in addition to finding errors in the ADF, our analysis also led to a better understanding of the behaviour the system

Z and high level Petri nets

High level Petri nets have tokens with values, traditionally called colors, and transitions that produce tokens in a functional way, using the consumed tokens as arguments of the function application. Large nets should be designed in a topdown approach and therefore we introduce a hierarchical net model which combines a data flow diagram technique with a high level Petri net model. We use Z to specify this net model, which is in fact the metamodel for specific systems. Specific models we specify partly by diagrams and partly in Z. We give some advantages and disadvantages of using Z in this way. Finally we show how to specify systems by means of an example

The key driver method

This chapter is a re-worked version of a paper for the International Conference on System Engineering and Applications (ICSSEA) 2006

Unitary symmetries, the symmetric group, and multiquark systems

Contains fulltext : mmubn000001_027884910.pdf (publisher's version ) (Open Access)Promotor : J. de Swart203 p