The Ramsey number, , of a graph G is the minimum integer N such that, in every 2-colouring of the edges of the complete graph on N vertices, there is a monochromatic copy of G. In 1975, Burr and Erdős posed a problem on Ramsey numbers of d-degenerate graphs, i.e., graphs in which every subgraph has a vertex of degree at most d. They conjectured that for every d there exists a constant c(d) such that for any d-degenerate graph G of order n.

In this paper we prove that for each such G. In fact, we show that, for every , sufficiently large n, and any graph H of order , either H or its complement contains a (d,n)-common graph, that is, a graph in which every set of d vertices has at least n common neighbours. It is easy to see that any (d,n)-common graph contains every d-degenerate graph G of order n. We further show that, for every constant C, there is an n and a graph H of order such that neither H nor its complement contains a -common graph.

If φ is a scattered order type, and μ is a cardinal, then there exists a scattered order type ψ such that holds.

A subgraph H in an edge-colouring is properly coloured if incident edges of H are assigned different colours, and H is rainbow if no two edges of H are assigned the same colour. We study properly coloured subgraphs and rainbow subgraphs forced in edge-colourings of complete graphs in which each vertex is incident to a large number of colours.

The history of music in the twentieth century is viewed as a process of expanding the sonic material of music to include all sound. Technological barriers to the full exploitation of the domain of sound are suggested as causing the process to take more time than it would otherwise due to cultural or aesthetic factors alone. Important historical developments in music over the last century are reconsidered to be, at least in part, strategies for circumventing technological limitations to manipulating and accessing all sound. Support for this perspective is found in the words of artists and composers of the time and in comparisons between the technologies available for creation in the visual and the sonic arts. Sound modelling is examined as a post all-sound paradigm holding promise for normalising the relationship between sound and music.

This paper gives an overview of electronic marketplaces which employ agent technology or similar techniques. Special attention is given to negotiation issues. A classification scheme for competitive negotiation depending on the type of the marketplace (business-to-business, business-to-consumer and consumer-to-consumer) and on the range of players (1:1, 1:n and n:m) is introduced. Furthermore, we distinguish between one-issue and multi-issue negotiation, and we consider crisp and fuzzy constraints on either negotiating side. Several existing electronic marketplaces and prototypes of marketplaces are discussed with respect to the classification schema. Our analysis shows that agent-based e-marketplaces are a promising area of e-commerce but they are still far away from real marketplaces. In conclusion we formulate some challenges for further research in the field of multi-agent electronic marketplaces with negotiation between agents.

This article suggests a framework for the articulation of ambiophonic and geometrical spaces in electroacoustic composition and performance. Space-ambiophony explores the global perception of space, which is derived from the archetypal perception of surrounding environments. The term applies to usually large-scale observation but it can also include shifts in the listener's attention from gestalt perception to micro-structural observation. A spatial analysis of Smalley's Base Metals demonstrates the methods by which space-ambiophony is integrated into the composition. In space-geometry, relations and analogies are established between composed sonic events and principles of geometry and stereometry. Three primordial geometrical elements, drawn from Wassily Kandinsky's theoretical work on painting, serve as metaphorical cells for the construction and projection of this type of space: the point, the line and the plane.

The interaction between the acoustic qualities of listening spaces, the configuration of loudspeakers, the composed space (sonic trajectories, background, foreground) and its projection by the interpreter in a concert, are all issues that occupy parts of the article.

Ontology mapping is seen as a solution provider in today's landscape of ontology research. As the number of ontologies that are made publicly available and accessible on the Web increases steadily, so does the need for applications to use them. A single ontology is no longer enough to support the tasks envisaged by a distributed environment like the Semantic Web. Multiple ontologies need to be accessed from several applications. Mapping could provide a common layer from which several ontologies could be accessed and hence could exchange information in semantically sound manners. Developing such mappings has been the focus of a variety of works originating from diverse communities over a number of years. In this article we comprehensively review and present these works. We also provide insights on the pragmatics of ontology mapping and elaborate on a theoretical approach for defining ontology mapping.

For most electroacoustic composers, ‘interactivity’ refers to technology which responds to input from a performer. For performers, in contrast, performance may be described as ‘interactive’ on many levels: interacting with acoustic musical interfaces (their instruments), communicating with composers and audiences, mediating the data of a score, negotiating prosthetic devices (microphones, loudspeakers, pedals, sensors), and interacting with invisible chamber music partners (whether backing tracks or responsive computer programs). There has been little public discussion about these issues. This paper will therefore discuss various elements of interactivity in electroacoustic music from the performer's perspective, with the goal of promoting and facilitating satisfying collaborations for both composers and performers. Discussions of pieces for flute and electronics will demonstrate various issues in performing with electronics; describe ways in which works and systems have been designed to work effectively as chamber music; and offer insights into the process of collaboration between composers, technologists and performers.

As the techniques used in creating audio art and electronic music become more diversified and increasingly use some sort of computer-oriented notation, the question of analysis of this wide repertoire is revisited. While there are still many obstacles in its study, this topic attracts more attention today than in the recent past. In this article, I emphasise the need to consider that, when analysing audio art and electronic music, technology, technique and musical style are to be taken in account. To this end, I introduce concepts put forth by the Russian Constructivists as a basis for reflection.

I have had a major interest in the performance practice issues in electronic and interactive systems over the years (see, for example, Kimura 1996). As a performer/composer often presenting pieces from the classical and other contemporary acoustic violin literature in traditional settings along with electronic works, and also as a teacher of interactive computer music performance at a conservatory where my students include highly trained performers, performance practice issues in computer music come up very frequently in association with the creative process. I tend to focus on creating MaxMSP patches that address a particular musical context or situation, rather than creating an elaborate versatile and reusable MaxMSP patch and then using that patch in a particular way to make music. This paper describes a few examples of my interest in this area: (i) System Aspects: Performance Practice Issues and Room Acoustics; (ii) ‘Pragmatic’ Programming and Performance of Interactive Music; and (iii) Creative Process and Interactive Computer Music.

Spiral Fiction is a piece of interactive performance staged by the authors in 2002. The paper provides detailed information about the technology used, the nature of the interactivity employed, the artists use of the Bodycoder System© and the aesthetic and theoretical issues arising out of the work. The paper addresses the problematic nature of the audience gaze, the seductive qualities of new technology, creative balance in the presence of new technologies and the problem of placing interactive performance along side analogue and single art form disciplines. The paper also explores the psychophysical nature of the interactivity associated with the Bodycoder System and will discuss cross-modal perception and sensation. The authors draw on aspects of postmodern theory to further expand their observations.

Knowledge-based systems have often been criticised for the limited theoretical base upon which they are constructed. This view asserts that systems are often developed in an ad hoc, individual way that leads to unmaintainable, unreliable and non-rigorous systems. The last decade, however, has seen an increased effort to produce methodologies to counter this view as well as continued research into validation and verification techniques. This paper presents a brief discussion of some of the important research in knowledge-based system life cycles and development methods. Methodologies are considered and are discussed in light of two sets of quality assurance criteria.

Technology influences all art, and therefore all music, including composition, performance and listening. It always has, and it always will. For example, technical developments in materials, mechanics and manufacturing were important factors that permitted the piano to supersede the harpsichord as the primary concert Western keyboard instrument by about 1800. And with each new technical development new performance issues have been introduced. Piano performance technique is quite different from harpsichord technique, and composers responded to these differences with new music ideas and gestures. The multiple relationships between technology and composer and performer are dynamic and of paramount importance to each party. And a true consideration of any aspect of music requires that all three areas be examined. This has always been a part of music, and so these relationships are inherently important within computer music. The difference is that electronic technology has caused a fundamental change for all aspects of music, a difference that is as pivotal in the history of Western music as was the shift from oral to written preservation of music over a thousand years ago, and then also the accessibility provided by printed music five hundred years ago. In computer music, all parties are always acutely aware of the presence and influence of machine technology in both the visual and audible realms.