A Critical Analysis of Synthesizer User Interfaces for Timbre

In this paper, we review and analyse categories of user interface used in hardware and software electronic music synthesizers. Problems with the user specification and modification of timbre are discussed. Three principal types of user interface for controlling timbre are distinguished. A problem common to all three categories is identified: that the core language of each category has no well-defined mapping onto the task languages of subjective timbre categories as used by musicians

Timbre space as synthesis space: towards a navigation based approach to timbre specification

Much research into timbre, its perception and classification over the last forty years has modelled timbre as an n-dimensional co-ordinate space or timbre space, whose axes are measurable acoustical quantities (variously, spectral density, simultaneity of partial onsets etc). Typically, these spaces have been constructed from data generated from similarity/dissimilarity listening tests, using multidimensional scaling (MDS) analysis techniques. Our current research is the computer assisted synthesis of new timbres using a timbre space search strategy, in which a previously constructed simple timbre space is used as a search space by an algorithm designed to synthesize desired new timbres steered by iterative user input. The success of such an algorithm clearly depends on establishing suitable mapping between its quantifiable features and its perceptual features. We therefore present here, firstly, some of the findings of a series of listening tests aimed at establishing the perceptual topography and granularity of a simple, predefined timbre space, and secondly, the results of preliminary tests of two search strategies designed to navigate this space. The behaviour of these strategies in a circumscribed space of this kind, together with the corresponding user experience is intended to provide a baseline to applications in a more complex space

The impact of regulation, ownership and business culture on managing corporate risk within the water industry

Although the specifics of water utility ownership, regulation and management culture have been explored in terms of their impact on economic and customer value, there has been little meaningful engagement with their influence on the risk environment and risk management. Using a literature review as the primary source of information, this paper maps the existing knowledge base onto two critical questions: what are the particular features of regulation, ownership and management culture which influence the risk dynamic, and what are the implications of these relationships in the context of ambitions for resilient organizations? In addressing these queries, the paper considers the mindful choices and adjustments a utility must make to its risk management strategy to manage strategic tensions between efficiency, risk and resilience. The conclusions note a gap in understanding of the drivers required for a paradigm shift within the water sector from a re-active to a pro-active risk management culture. A proposed model of the tensions between reactive risk management and pro-active, adaptive risk management provides a compelling case for measured risk management approaches which are informed by an appreciation of regulation, ownership and business culture. Such approaches will support water authorities in meeting corporate aspirations to become "high reliability" services while retaining the capacity to out-perform financial and service level targets

Land use in rural New Zealand: spatial land use, land-use change, and model validation

Abstract Land is an important social and economic resource. Knowing the spatial distribution of land use and the expected location of future land-use change is important to inform decision makers. This paper documents and validates the baseline land-use maps and the algorithm for spatial land-use change incorporated in the Land Use in Rural New Zealand model (LURNZ). At the time of writing, LURNZ is the only national-level land-use model of New Zealand. While developed for New Zealand, the model provides an intuitive algorithm that would be straightforward to apply to different locations and at different spatial resolutions. LURNZ is based on a heuristic model of dynamic land-use optimisation with conversion costs. It allocates land-use changes to each pixel using a combination of pixel probabilities in a deterministic algorithm and calibration to national-level changes. We simulate out of sample and compare to observed data. As a result of the model construction, we underestimate the “churn” in land use. We demonstrate that the algorithm assigns changes in land use to pixels that are similar in quality to the pixels where land-use changes are observed to occur. We also show that there is a strong positive relationship between observed territorial-authority-level dairy changes and simulated changes in dairy area

How well do high resolution models reproduce tropical convection?

Cascade is a multi-institution project studying the temporal and spatial organization of tropical convective systems. While cloud resolving numerical models can reproduce the observed diurnal cycle of such systems they are sensitive to the chosen resolution. As part of this effort, we are comparing results from the Met. Office Unified Model to data from the Global Earth Radiation Budget satellite instrument over the African Monsoon Interdisciplinary Analyses region of North Africa. We use a variety of mathematical techniques to study the outgoing radiation and the evolution of properties such as the cloud size distribution. The effectiveness of various model resolutions is tested with a view to determining the optimum balance between resolution and the need to reproduce the observations

A CASE tool for demonstrating Z specifications

The CASE tool described, is designed to enable software engineers to produce a faithful animation of specifications written in Z. Desirable properties which animations of this kind should possess, and which have guided the authors in developing the tool, are the following: the executable code (i.e., the animation) must be easy to produce; the structure of the code should not be too far removed from the Z; and the animation should be sufficiently user friendly to enable a client to understand and interact with it. The CASE tool is based around the program development tool known as CRYSTAL. CRYSTAL is sold as an expert system shell by Intelligent Environments Ltd. It is essentially a rule-based programming language offering excellent input, output, and menu facilities, as well as all the standard features expected of any expert system shell

Cycle decompositions in k-uniform hypergraphs

We show that k-uniform hypergraphs on n vertices whose codegree is at least (2/3+o(1))n can be decomposed into tight cycles, subject to the trivial divisibility conditions. As a corollary, we show those graphs contain tight Euler tours as well. In passing, we also investigate decompositions into tight paths.In addition, we also prove an alternative condition for building absorbers for edge-decompositions of arbitrary k-uniform hypergraphs, which should be of independent interest

Cycle decompositions in k-uniform hypergraphs

We show that k-uniform hypergraphs on n vertices whose codegree is at least (2/3+o(1))n can be decomposed into tight cycles, subject to the trivial divisibility conditions. As a corollary, we show those graphs contain tight Euler tours as well. In passing, we also investigate decompositions into tight paths.In addition, we also prove an alternative condition for building absorbers for edge-decompositions of arbitrary k-uniform hypergraphs, which should be of independent interest