No abstract available.

No abstract available.

No abstract available.

10.1016/0004-3702(95)90030-6

Autocorrelation has the potential to provide a means for detecting boundaries which delimit musical events, but it must be used carefully. Attempts to deal with either rhythmic or pitch data in isolation yield results which are inconclusive, at best. Examples are given of data which provide a more realistic abstraction of the signal which is actually perceived as a real time experience. Nevertheless, it remains to be seen whether or not the ability to recognize patterns demonstrated here lies at the heart of the perception of musical events. Thus, autocorrelation should be considered as one of several alternatives for solving the problem of detecting boundaries between musical events.

This is a study of two attempts to develop quantitative models of timing in music performance, one based on connectionism and the other involving the autocorrelation function. The former is concerned with the ‘quantization problem’ of interpreting durations of time from a musical performance as note shapes which represent duration in music notation. The latter is an attempt to represent what makes such performances ‘‘expressive ’. These models were derived by Peter Desain, but there is a paucity of validating data in the published literature. Attempts to collect additional data have revealed significant shortcomings in both models, as well as methodological flaws. The most important problem is that the attempt to solve the quantization problem lacks any representation of high-level structure. As a result, if the music itself tends to be based on relatively irregular rhythmic patterns, the connectionist model can distort even a metronome-perfect performance, rather than recognizing the correct temporal patterns. Attempts are made to explain how these shortcomings may have arisen.

Operational requirements are qualities which influence a software system's entire development cycle. The investigation reported here concentrated on three of the most important operational requirements: reliability via fault tolerance, growth, and availability. Accommodation of these requirements is based on an approach to functional decomposition involving representation in terms of potentiafly independent processors, called virtual machines. Functional requirements may be accommodated through hierarchical decomposition of virtual machines, while performance requirements may be associated with individual virtual machines. Virtual machines may then be mapped to a representation of a confilguration of physical resources, so that performance requirements may be reconciled with available performance characteristics.

The development of a distributed system de dicated to a single mission entails difficulties not encountered in the development of a corres ponding centralized system. The considerable flexibility Allowed in selecting resources and the resulting potential for complexity of interaction among these resources necessitates a new view of the entire development process. It must be recognized, at the outset, that there are two facets to all design activities in this process. On the one hand, the task of logical design is primarily concerned with formulating a suitable elaboration of system requirements; complementing this task, physical design is concerned with the realization of these requirements in terms of an ultimate implementation. A two-dimensional framework is presented as a context for the task of logical design. In one dimension the system is represented as a hierarchy of partitions of responsibilities for requirements, while the second dimension addresses the topologies of interconnections among the blocks in each partition. Requirements elaboration may then be formulated in terms of issues involving the selection of a specific interconnection topology at each level of the hierarchy. These issues may be ex pressed in terms of a sequence of questions concerning interconnection which may be posed at each level. System requirements may then be elaborated in such a way that they will serve to answer these questions.

At the 1968 NATO Conference on Software Engineering,1 Edsger W. Dijkstra remarked that he found his position, as a teacher, analogous to that of a teacher of composition at a school of music. This paper wishes to pursue this analogy in greater detail. In particular, the role of style in computer science education is assessed in terms of the corresponding role it plays in music education.

There is a need for a simple mechanized way to design, update and produce final copies of scores of Labanotation, a symbolic, graphical language for the recording of body movement used by choreographers, anthropologists, psychologists and therapists. This paper discusses the design and implementation of a machine-independent data structure for Labanotation and its application in an interactive storage, retrieval and editing system.