Generic approach for deriving reliability and maintenance requirements through consideration of in-context customer objectives

Not all implementations of reliability are equally effective at providing customer and user benefit. Random system failure with no prior warning or failure accommodation will have an immediate, usually adverse impact on operation. Nevertheless, this approach to reliability, implicit in measurements such as ‘failure rate’ and ‘MTBF’, is widely assumed without consideration of potential benefits of pro-active maintenance. Similarly, it is easy to assume that improved maintainability is always a good thing. However, maintainability is only one option available to reduce cost of ownership and reduce the impact of failure. This paper discusses a process for deriving optimised reliability and maintenance requirements through consideration of in-context customer objectives rather than a product in isolation

Task oriented nonlinear control laws for telerobotic assembly operations

The goal of this research is to achieve very intelligent telerobotic controllers which are capable of receiving high-level commands from the human operator and implementing them in an adaptive manner in the object/task/manipulator workspace. Initiatives by the authors at Integrated Systems, Inc. to identify and develop the key technologies necessary to create such a flexible, highly programmable, telerobotic controller are presented. The focus of the discussion is on the modeling of insertion tasks in three dimensions and nonlinear implicit force feedback control laws which incorporate tool/workspace constraints. Preliminary experiments with dual arm beam assembly in 2-D are presented

From 2D Integrable Systems to Self-Dual Gravity

We explain how to construct solutions to the self-dual Einstein vacuum equations from solutions of various two-dimensional integrable systems by exploiting the fact that the Lax formulations of both systems can be embedded in that of the self-dual Yang--Mills equations. We illustrate this by constructing explicit self-dual vacuum metrics on $\R^2\times \Sigma$, where $\Sigma$ is a homogeneous space for a real subgroup of SL(2, \C) associated with the two-dimensional system.Comment: 9 pages, LaTex, no figure

On a low energy bound in a class of chiral field theories with solitons

A low energy bound in a class of chiral solitonic field theories related the infrared physics of the SU(N) Yang-Mills theory is established.Comment: Plain Latex, 8 pages, no figure

Massive Elementary Particles and Black Holes

An outstanding problem posed by Einstein's general theory of relativity to the quantum theory of point particle fields is the fate of a massive point particle; for, in the classical solutions of Einstein's theory, such a system should be a black hole. We use exact results in a new approach to quantum gravity to show that this conclusion is obviated by quantum loop effects. Phenomenological implications are discussedComment: 11 pages; 1 figure; improved text relating to asymptotic safet

After Regions: what next for local enterprise partnerships?

Standing out as an oddity in comparison to the convergence of policy across EU nations whereby the merits of regional apparatus – however defined – for administering development support appear to be accepted, the UK Government has abandoned England’s experiment with regionalism. Under the banner of localism, providing the thinnest of masks for swingeing public expenditure cuts, sub-national development activity (encompassing planning, regeneration, infrastructure development, enterprise support and spatial leadership) is in the throes of considerable economic shifts, policy flux and institutional upheaval (Ward & Hardy, 2012). This article attempts to address some of the questions posed in The regional lacuna: a preliminary map of the transition from Regional Development Agencies to Local Economic Partnerships (Pugalis, 2011) and helps to advance some of the points relating to the emerging sub-national development landscape published in recent issues of Regions (e.g. Bailey, 2011). The purpose is to take stock of policy developments underway by means of a post-regional sub-national review in order to outline the future development trajectory of Local Enterprise Partnerships

Demonstration of displacement-noise-free interferometry using bi-directional Mach–Zehnder interferometers

We have demonstrated displacement- and frequency-noise-free laser interferometry (DFI) by partially implementing a recently proposed optical configuration using bi-directional Mach–Zehnder interferometers (MZIs). This partial implementation, the minimum necessary to be called DFI, has confirmed the essential feature of DFI: the combination of two MZI signals can be carried out in a way that cancels the displacement noise of the mirrors and beam splitters while maintaining gravitational-wave signals. The attained maximum displacement noise suppression was 45 dB

From 2D conformal to 4D self-dual theories: quaternionic analyticity

It is shown that self-dual theories generalize to four dimensions both the conformal and analytic aspects of two-dimensional conformal field theories. In the harmonic space language there appear several ways to extend complex analyticity (natural in two dimensions) to quaternionic analyticity (natural in four dimensions). To be analytic, conformal transformations should be realized on $CP^3$, which appears as the coset of the complexified conformal group modulo its maximal parabolic subgroup. In this language one visualizes the twistor correspondence of Penrose and Ward and consistently formulates the analyticity of Fueter.Comment: 24 pages, LaTe