The paper describes a case study whose aim is to verify a set of hypotheses related to the management of documents during the evolution of Information Systems. The idea is to distinguish the evolution documents (documents that support the evolution of long living applications) from the development documents (related to a single development step of the application life). The evolution documents are derived from the development documents using a minimalist approach and a cost-benefit analysis. The study involved ninety applications of a large information system of a retail company. We describe the context and the method of the study. We present the results and discuss both validity and scope. The evolution documents are a collection of selected parts of the development documents with a size reduction (in pages) of an order of magnitude. The study identifies minimal sets of document types for classes of software applications. These sets are organized into patterns of evolution documents. All the evolution documents are stored into a common knowledge base managed through a wiki-based tool.

The paper compares the models used for software quality evaluation to the modelling approach of other engineering fields. The conclusion is that, while large efforts have been devoted to the definition of measurable attributes and related measures, product models specifically developed for measuring quality characteristics are until now not sufficiently explored. We explore the concept of "quality-oriented specialized product models" and we claim that this is an important ingredient for an engineering approach to the software quality measurement. We describe an example of this type of models for measuring the security of a specific type of copy protection mechanisms. The model forecasts the amount of time a hypothetical attacker would need to break the protection.

Scientific and engineering software is often produced by integration of existing software components of the size of a whole program. However, on the average, scientific software was not developed for reusability and is quite distant from the user model of the application problem; integration and retrofitting is as such a costly process. An architecture, methodology and several C++ class libraries for supporting integration are introduced. The architecture separates a software component layer, and an integration layer. The latter in based on the concept of software model, that is an abstraction of components and a representation of the system differing from its actual physical structure. The methodology is based on matching needs with existing models. The C++ class libraries are explained in some detail. The application to two major systems is analysed and the ideas behind seven other systems are briefly outlined. Some lessons learned are summarised in the conclusions.

Microseismic networks, equipped with digital recorders triggered by STA/LTA threshold, may be affected by a high number of false triggers. These cause wastage of computing resources (cpu time and mass storage) and is unacceptable in managing data from many networks. The aim of this study is to test the capability to reject false triggers by statistical segmentation (as proposed by Chen). The sample set includes 580 readable microquakes and 2,310 other signals including spurious noises and unreadable quakes. Signals are partitioned into fixed length sections. For every couple of contiguous sections the waveform statistical difference is measured by computing the entropy distance. The features vector characterizing a signal is composed of: the maximum value of entropy distance, the occurrence time of this maximum value and the AR(3) coefficients of the section beginning at the occurrence time. Several classification methods have been used: the best results come from the Fisher classifier applied to the features vectors with dimensionality reduced by the Foley-Sammon transform.