Data-Oblivious Stream Productivity

We are concerned with demonstrating productivity of specifications of infinite streams of data, based on orthogonal rewrite rules. In general, this property is undecidable, but for restricted formats computable sufficient conditions can be obtained. The usual analysis disregards the identity of data, thus leading to approaches that we call data-oblivious. We present a method that is provably optimal among all such data-oblivious approaches. This means that in order to improve on the algorithm in this paper one has to proceed in a data-aware fashion

Contributions to Mokken's nonparametric item response theory

In this study, the item response models proposed by Mokken (1971) are discussed, and further developed. In these item response models the relation between observable response behavior on an item and latent characteristics of persons and items is described by means of an item characteristic function. Since these functions are not defined parametrically in Mokken's approach, the item response models are called nonparametric. The models proposed by Mokken can be used to scale persons and items on a single dimension. This dimension represents the quantitative measurement scale of a psychological or some other attribute. By measuring persons by means of tests or questionnaires which comply with an item response model, assertions about behavior are psychometrically well founded. ... Zie: Summary

The Dutch deposit of electronic publications (DNEP) - 1995-2000

In 1993 the Internet took off with the introduction of HTML and the first browser (Mosaic1). Two years later, in 1995, the Koninklijke Bibliotheek decided to start a series of experiments and projects which would lead to a deposit system for Dutch Electronic Publications. In the same year the Koninklijke Bibliotheek made a policy decision to include electronic material into its deposit. That marked the start of the Dutch Deposit for Electronic Publications (DNEP2). Both as an operational service and at the same time as a test-bed for research into digital archiving. The Koninklijke Bibliotheek has a staff of 254.5 FTE3. The ICT-department has 15 FTE (about 6%).The ICT-department is responsible for the systems management of the operational systems, for the support of the end-users and for research and development. Apart from the R&D done in the ICTdepartment the Koninklijke Bibliotheek also has a department of library research (see the website4 of the Koninklijke Bibliotheek for more information). In the first few years a lot of experiments were done. Various hardware and software was tested and research was done on issues such as metadata, the number of electronic publications available, how to process them in the library etc. At the end of 1998 the Koninklijke Bibliotheek decided that the time was ripe to make the next step. This was the implementation of the DNEP on a large scale and as part of the normal workflow inside the library departments