Accuracy: The fundamental requirement for voting systems

There have been several attempts to develop a comprehensive account of the requirements for voting systems, particularly for public elections. Typically, these approaches identify a number of "high level" principals which are then refined either into more detailed statements or more formal constructs. Unfortunately, these approaches do not acknowledge the complexity and diversity of the contexts in which voting takes place. This paper takes a different approach by arguing that the only requirement for a voting system is that it is accurate. More detailed requirements can then be derived from this high level requirement for the particular context in which the system is implemented and deployed. A general, formal high level model for voting systems and their context is proposed. Several related definitions of accuracy for voting systems are then developed, illustrating how the term "accuracy" is in interpreted in different contexts. Finally, a context based requirement for voting system privacy is investigated as an example of deriving a subsidiary requirement from the high level requirement for accuracy

Multi‐diagnostic multi‐model ensemble forecasts of aviation turbulence

Turbulence is one of the major weather hazards to aviation. Studies have shown that clear‐air turbulence may well occur more frequently with future climate change. Currently the two World Area Forecast Centres use deterministic models to generate forecasts of turbulence. It has been shown that the use of multi‐model ensembles can lead to more skilful turbulence forecasts. It has also been shown that the combination of turbulence diagnostics can also produce more skilful forecasts using deterministic models. This study puts the two approaches together to expand the range of diagnostics to include predictors of both convective and mountain wave turbulence, in addition to clear‐air turbulence, using two ensemble model systems. Results from a 12 month global trial from September 2016 to August 2017 show the increased skill and economic value of including a wider range of diagnostics in a multi‐diagnostic multi‐model ensemble

Deriving Information Requirements from Responsibility Models

This paper describes research in understanding the requirements for complex information systems that are constructed from one or more generic COTS systems. We argue that, in these cases, behavioural requirements are largely defined by the underlying system and that the goal of the requirements engineering process is to understand the information requirements of system stakeholders. We discuss this notion of information requirements and propose that an understanding of how a socio-technical system is structured in terms of responsibilities is an effective way of discovering this type of requirement. We introduce the idea of responsibility modelling and show, using an example drawn from the domain of emergency planning, how a responsibility model can be used to derive information requirements for a system that coordinates the multiple agencies dealing with an emergency

Akubras to Hard Hats: Easing Skills Shortages through Labour Harmonisation Strategies

This article examines skill and labour shortages within rural agricultural industries in Western Australia. It draws on primary and secondary data, including 600 survey respondents in the sector. It is determined that there may be a shortage of farm workers during the busy seasons, while they are unemployed during the low seasons. Consequently, it is proposed that a human capability framework is utilised to encourage farm owners and (or) workers to consider the potential for labour-harmonisation (LH) strategies which would allow workers to transit between working on the land during the busy seasons and in mining during the low seasons. The outcomes of the study are considered in relation to indicators of precarious work illustrating that LH could enable an easing of labour shortages for both the farming and mining sectors, while providing benefits for the respective workers, employers, and the region in general

A comparison of incompressible limits for resistive plasmas

The constraint of incompressibility is often used to simplify the magnetohydrodynamic (MHD) description of linearized plasma dynamics because it does not affect the ideal MHD marginal stability point. In this paper two methods for introducing incompressibility are compared in a cylindrical plasma model: In the first method, the limit $\gamma \to \infty$ is taken, where $\gamma$ is the ratio of specific heats; in the second, an anisotropic mass tensor $\mathbf{\rho}$ is used, with the component parallel to the magnetic field taken to vanish, $\rho_{\parallel} \to 0$. Use of resistive MHD reveals the nature of these two limits because the Alfv\'en and slow magnetosonic continua of ideal MHD are converted to point spectra and moved into the complex plane. Both limits profoundly change the slow-magnetosonic spectrum, but only the second limit faithfully reproduces the resistive Alfv\'en spectrum and its wavemodes. In ideal MHD, the slow magnetosonic continuum degenerates to the Alfv\'en continuum in the first method, while it is moved to infinity by the second. The degeneracy in the first is broken by finite resistivity. For numerical and semi-analytical study of these models, we choose plasma equilibria which cast light on puzzling aspects of results found in earlier literature.Comment: 14 pages, 10 figure

Osteology and myology of the head and neck of the pied-billed grebes (Podilymbus)

http://deepblue.lib.umich.edu/bitstream/2027.42/56383/1/MP139.pd

How cultural capital emerged in Gilded Age America: musical purification and cross-class inclusion at the New York Philharmonic

This article uses a new database of subscribers to the New York Philharmonic to explore how high culture became a form of socially valuable capital in late-19th-century America. The authors find support for the classic account of high culture?s purification and exclusiveness, showing how over the long Gilded Age the social elite of New York attended the Philharmonic both increasingly and in more socially patterned ways. Yet they also find that the orchestra opened up to a new group of subscribers hailing from an emerging professional, managerial, and intellectual middle class. Importantly, the inclusion of this new audience was segregated: they did not mingle with elites in the concert hall. This segregated inclusion paved a specific way for the constitution of cultural capital. It meant that greater purity and greater inclusiveness happened together, enabling elite cultural participation to remain distinctive while elite tastes acquired broader social currency

Stability and transport of parallel velocity shear driven mode with negative magnetic shear

The linear and quasilinear behavior of the drift-like perturbation with a parallel velocity shear is studied in a sheared slab geometry. Full analytic studies show that when the magnetic shear has the same sign as the second derivative of the parallel velocity with respect to the radial coordinate, the linear mode may become unstable and turbulent momentum transport increases. On the other hand, when the magnetic shear has opposite sign to the second derivative of the parallel velocity, the linear mode is completely stabilized and turbulent momentum transport reduces

Searching of gapped repeats and subrepetitions in a word

A gapped repeat is a factor of the form $uvu$ where $u$ and $v$ are nonempty words. The period of the gapped repeat is defined as $|u|+|v|$. The gapped repeat is maximal if it cannot be extended to the left or to the right by at least one letter with preserving its period. The gapped repeat is called $\alpha$-gapped if its period is not greater than $\alpha |v|$. A $\delta$-subrepetition is a factor which exponent is less than 2 but is not less than $1+\delta$ (the exponent of the factor is the quotient of the length and the minimal period of the factor). The $\delta$-subrepetition is maximal if it cannot be extended to the left or to the right by at least one letter with preserving its minimal period. We reveal a close relation between maximal gapped repeats and maximal subrepetitions. Moreover, we show that in a word of length $n$ the number of maximal $\alpha$-gapped repeats is bounded by $O(\alpha^2n)$ and the number of maximal $\delta$-subrepetitions is bounded by $O(n/\delta^2)$. Using the obtained upper bounds, we propose algorithms for finding all maximal $\alpha$-gapped repeats and all maximal $\delta$-subrepetitions in a word of length $n$. The algorithm for finding all maximal $\alpha$-gapped repeats has $O(\alpha^2n)$ time complexity for the case of constant alphabet size and $O(n\log n + \alpha^2n)$ time complexity for the general case. For finding all maximal $\delta$-subrepetitions we propose two algorithms. The first algorithm has $O(\frac{n\log\log n}{\delta^2})$ time complexity for the case of constant alphabet size and $O(n\log n +\frac{n\log\log n}{\delta^2})$ time complexity for the general case. The second algorithm has $O(n\log n+\frac{n}{\delta^2}\log \frac{1}{\delta})$ expected time complexity