The rhythmic dimension in fiddle-playing as the music moves to newer performing and learning contexts

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Extended Nonnegative Tensor Factorisation Models for Musical Sound Source Separation

Recently, shift-invariant tensor factorisation algorithms have been proposed for the purposes of sound source separation of pitched musical instruments. However, in practice, existing algorithms require the use of log-frequency spectrograms to allow shift invariance in frequency which causes problems when attempting to resynthesise the separated sources. Further, it is difficult to impose harmonicity constraints on the recovered basis functions. This paper proposes a new additive synthesis-based approach which allows the use of linear-frequency spectrograms as well as imposing strict harmonic constraints, resulting in an improved model. Further, these additional constraints allow the addition of a source filter model to the factorisation framework, and an extended model which is capable of separating mixtures of pitched and percussive instruments simultaneously

Sound Source Separation using Shifted Non-negative Tensor Factorisation

Recently, shifted non-negative Matrix Factorisation was developed as a means of separating harmonic instruments from single channel mixtures. However, in many cases two or more channels are available, in which case it would be advantageous to have a multichannel version of the algorithm. To this end, a shifted Non-negative Tensor Factorisation algorithm is derived, which extends shifted Non-negative Matrix Factoristiaon to the multi channel case. The use of this algorithm for multi-channel sound source separation of harmonic instruments is demonstrated. Further, it is shown that the algorithm can be used to perform Non-negative Tensor Deconvolution, to separate sound sources which have time evolving spectra from multi-channel signals

Key Signature Estimation

The problem of automatic key signature detection has been the focus of much research in recent years. Previous methods of key estimation have focused on chromagrams and key profiling techniques. This paper presents a remarkably simple but effective method of estimating key signature from musical recordings. The algorithm introduces the keyogram , a concept resembling the chromagram, and is aimed for use on traditional Irish music. The keyogram is a measure of the likelihood of each possible major key signature based on a masked scoring system

The metaphor imperative : a study of metaphor's assuaging role in poetic composition from Ovid to Alice Oswald

Part I of the thesis considers the nature and function of metaphor in the articulation of both poetic theme and of poetic self. Using close analysis of texts by Ovid, Shakespeare, George Herbert and a number of contemporary poets, and drawing on material from both published and unpublished interviews which I undertook with Alice Oswald, Glyn Maxwell and Andrew Motion, (the transcripts of which are included in the appendices), this thesis uses metaphor theory, literary criticism and cognitive poetic criticism to argue that the assuaging role of metaphor is fundamental at critical junctures of poetic composition. Chapter One provides a historical survey of metaphor theory. Chapter Two, in order to determine the best methodology for my analysis of the key thesis texts, contrasts three different readings of Shakespeare’s Sonnet 73. Chapter Three suggests the model of Ovidian metamorphosis as a means to examine the assuaging role of metaphor in crisis of consciousness and utterance. The dialectic of sameness and difference, a key property of metaphor, is shown to be intimately connected with the imperative for assuagement in the modern lyric poet. Chapter Four explores a number of ways in which metaphor is deployed by George Herbert to overcome the personal and poetic inhibitions he experiences as a result of his intimate awareness of a listening God. Chapter Five examines Andrew Motion’s movement away from the metonymic towards the metaphoric mode in The Customs House. Chapter Six analyses how Alice Oswald, by creating a radically innovative metaphoric mapping between biography and simile pairs assuages the long litany of violent deaths drawn from Homer’s Iliad. Chapter Seven examines the way Glyn Maxwell in The Sugar Mile, embraces dramatic analogue and metaphor as a means to address the horror of 9/11. All of the poets examined in the thesis are using metaphor to render the incomprehensible comprehensible. Part II of the thesis consists of my own poems

Virtualisation: A case study in database administration laboratory work

This paper discusses the issues involved in using virtual machines to teach database administration concepts and the associated issues in a university student environment. Previous work on using virtual machines in system/network administration university labs is reviewed as well as the use of virtual machines in a database development environment. A virtual machine project for a Virtual Information Technology Teaching Laboratory (VITTL) using central servers offering a potential solution is described. This solution provides a secure environment with each student isolated from others with their own virtual machines

Resynthesis Methods for Sound Source Separation using Shifted Non-negative Factorisation Models

Recently, techniques such as shifted 2D non-negative matrix factorisation and shifted 2D non-negative tensor factorisations have been proposed as methods for separating harmonic musical instruments from single and multi-channel mixtures. However, these methods require the use of a Constant Q transform, for which no true inverse exists. This has adverse effects on the quality of the resynthesis of the separated sources. In this paper, a number of different resynthesis methods are investigated in order to determine the best approach to resynthesi