We make some observations concerning the set C*n of real nonnegative, symmetric and diagonally dominant matrices of order n. This set is a convex cone and we determine its extreme rays. From this we derive different results, ...

This paper investigates and formally compares the expressive power of dimensional (i.e., spatial, temporal, and spatio-temporal) query languages, where the dimensional extensions are supported in terms of ADTs (abstract ...

An important problem in image analysis is to segment an image into regions with different class-labels. This is releveant in applications in medicine and cartography. In a proper statistical framework this problem may be ...

This document gives an overview the standard methods used to model and analyze the performance of queuing systems. This includes both analytical techniques and simulation methodology. Simulation must be used when the ...

A discrete-event simulation environment, called GMSim, based on the generalized semi-Markov process (GSMP) framework is described. The tool is completely generic and extendible by Tcl script programming. Application specific ...

We study the concept matrix majorization: for two real matrices A and B having m rows we say that A majorizes B if there is a row-stochastic matrix X with AX = B. A special case is classical notion of vector ma- jorization. ...

Given a graph G with a specified root node r. A spanning tree in G where each node has distance at most 2 from r is called a 2-hop spanning tree. For given edge weights the 2-hop spanning tree problem is to find a minimum ...

The analysis of chaotic time series requires proper reconstruction of the state space from the available data in order to successfully estimate invariant properties of the embedded attractor. Using the correlation dimension, ...

We de ne a specialization inheritance mechanism for object-oriented programming, admitting covariant rede nition of both methods and instance variables in subclassing. We investigate on the semantic weakness that makes ...

We give a purely syntactical, equational characterization of the poly-time functions on any constructor data structure (free algebra). The equations defining a function f have the shape of simple patterns: (f (c y1 : : ...

ABEL is a wide spectrum language developed at the University of Oslo. The applicative core of ABEL is a typed first order language with subtypes and partial functions. The paper presents a constructive fragment of the core, ...

“Abstraction” is used both for denoting relations in the problem domain of an information system, and for denoting relations inside software and hardware of a computer. This calls for a clarification of the concept, such ...

We discuss how the 1'st order specification and programming language ABEL could be extended with higher order functions. Several issues arise, related to subtyping, parameterization, strictness of generators and defined ...

Because of the close connection between computer systems and organizations, organizational aspects should be taught in system development courses. Dataflow diagramming is a frequently taught technique that can model formal ...

Functional integration is the compatibility between the structure, culture and competence of an organization and its computer systems, specifically the availability of data and functionality and the consistency of user ...