A curvilinear snake arm robot with gripper-axis fibre-optic image processor feedback

The official version of this article can be found at the link below.A curvilinear robot constructed from a number of modular flexible sections of fixed length and diameter but independently controlled radius and direction of curvature has been equipped with an optical fibre image guide transmitting images from between the gripper jaws to the remote TV camera of Microvision-100, a microcomputer controlled real-time DMA-based vision System that is easily trained to recognise the shape, position and orientation of components. The gripper position and orientation is controlled by feedback from the vision System, the action taken depending on component recognition and inspection for defects. Redundant degrees of freedom enable the curvilinear robot to avoid obstacles and work in confined spaces.The research programme described in this paper is supported by the U.K. Science and Engineering Research Council

Dispersion of biased swimming microorganisms in a fluid flowing through a tube

Classical Taylor-Aris dispersion theory is extended to describe the transport of suspensions of self-propelled dipolar cells in a tubular flow. General expressions for the mean drift and effective diffusivity are determined exactly in terms of axial moments, and compared with an approximation a la Taylor. As in the Taylor-Aris case, the skewness of a finite distribution of biased swimming cells vanishes at long times. The general expressions can be applied to particular models of swimming microorganisms, and thus be used to predict swimming drift and diffusion in tubular bioreactors, and to elucidate competing unbounded swimming drift and diffusion descriptions. Here, specific examples are presented for gyrotactic swimming algae.Comment: 20 pages, 4 figures. Published version available at http://rspa.royalsocietypublishing.org/content/early/2010/02/09/rspa.2009.0606.short?rss=

Metabolic rate meter and method

A method is described for measuring the dynamic metabolic rate of a human or animal. The ratio of the exhaled carbon dioxide to a known amount of C(13)02 introduced into the exhalation is determined by mass spectrometry. This provides an instantaneous measurement of the carbon dioxide generated

Peer assessment of research: how many publications per staff?

The UK's higher education funding councils have proposed reducing the number of submitted outputs from four to three in the forthcoming Research Excellence Framework to reduce the burden on panel members. This reduction is considered to be sufficient for panels to form a robust view of the achievements of individuals and their departments. The key issue is whether the subject panels would have sufficient information to judge the quality of research at departmental level with details of only three outputs per staff. Two journal quality indicators are used in this note to test the assumption that three publications is likely to be as useful to the panels as four to measure research quality in three cognate units of assessment (business & management, economics & econometrics and accounting & finance). In fact, the results indicate that two publications would be sufficient, thereby providing more time for a careful assessment of submitted outputs

The politics of policy resistance: reconstructing higher education in Kosovo

This article considers attempts to incorporate lessons and transfer policies from Britain in the reconstruction of Higher Education in Kosovo after 1999. In doing so, it employs aspects of the lesson-drawing framework developed by Rose (1991 and 2001) and the related concepts of policy transfer and policy diffusion. Drawing on contributions from anthropology and democratization studies, we suggest development of the public policy frameworks for lesson drawing and policy transfer in circumstances characterised by asymmetric interdependence, in which the tactics and strategies of policy resistance by ‘subordinate’ recipient actors can be crucial. This article details the nature of policy resistance and sets out hypotheses for future research

Numerical investigation of the effects of pedestrian barriers on aeroelastic stability of a proposed footbridge

A numerical investigation into the aerodynamic characteristics and aeroelastic stability of a proposed footbridge across a motorway in the north of England has been undertaken. The longer than usual span, along with the unusual nature of the pedestrian barriers, indicated that the deck configuration was likely to be beyond the reliable limits of the British design code BD 49/01. In particular, the investigation focussed on the susceptibility of the bridge due to flutter, and to assess if the design wind speeds could be met satisfactorily. The calculations were performed using the discrete vortex method, DIVEX, developed at the Universities of Glasgow and Strathclyde. DIVEX has been successfully validated on a wide range of problems, including the aeroelastic response of bridge deck sections. The proposed deck configuration, which incorporated a pedestrian barrier comprised of angled flat plates, was found to be unstable at low wind speeds with the plates having a strong turning effect on the flow at the leading edge of the deck. DIVEX was used to assess a number of alternative design options, investigating the stability with respect to flutter for each configuration. Reducing the number of flat plates and their angle to the deck lessened the effect of the barrier on the overall aerodynamic characteristics and increased the stability of the bridge to an acceptable level, with the critical flutter speed in excess of the specified design speed

String loop corrections to gauge and Yukawa couplings

We report on the recent progress in computing the effective supergravity action from superstring scattering amplitudes beyond the tree approximation. We discuss the moduli-dependent string loop corrections to gauge, gravitational and Yukawa couplings.Comment: 11 pages, CPTH-C218.0193 (Based on talks presented at the Rome Workshop STRINGS 92, at the 7th Meeting of the American Physical Society, and at the 26th Erice Workshop: ``From Superstrings to Supergravity"

On the deduction of galaxy abundances with evolutionary neural networks

A growing number of indicators are now being used with some confidence to measure the metallicity(Z) of photoionisation regions in planetary nebulae, galactic HII regions(GHIIRs), extra-galactic HII regions(EGHIIRs) and HII galaxies(HIIGs). However, a universal indicator valid also at high metallicities has yet to be found. Here, we report on a new artificial intelligence-based approach to determine metallicity indicators that shows promise for the provision of improved empirical fits. The method hinges on the application of an evolutionary neural network to observational emission line data. The network's DNA, encoded in its architecture, weights and neuron transfer functions, is evolved using a genetic algorithm. Furthermore, selection, operating on a set of 10 distinct neuron transfer functions, means that the empirical relation encoded in the network solution architecture is in functional rather than numerical form. Thus the network solutions provide an equation for the metallicity in terms of line ratios without a priori assumptions. Tapping into the mathematical power offered by this approach, we applied the network to detailed observations of both nebula and auroral emission lines in the optical for a sample of 96 HII-type regions and we were able to obtain an empirical relation between Z and S23 with a dispersion of only 0.16 dex. We show how the method can be used to identify new diagnostics as well as the nonlinear relationship supposed to exist between the metallicity Z, ionisation parameter U and effective (or equivalent) temperature T*.Comment: Accepted for publication in PASP. 6 pages, 2 figure

Charles W. Peach, palaeobotany and Scotland

The move south from Wick to the city of Edinburgh in 1865, some four years after retirement from the Customs service, provided Charles W. Peach with new opportunities for fossil-collecting and scientific networking. Here he renewed and maintained his interest in natural history and made significant palaeobotanical collections from the Carboniferous of the Midland Valley of Scotland. These are distinguished by some interesting characteristics of their documentation which the following generations of fossil collectors and researchers would have done well to emulate. Many of his fossil plant specimens have not only the locality detail,but also the date, month and year of collection neatly handwritten on attached paper labels; as a result, we can follow Peach's collecting activities over a period of some 18 years or so. Comments and even illustrative sketches on the labels of some fossils give us first-hand insight into Peach's observations. Study of these collections now held in National Museums Scotland reveals a pattern of collecting heavily biased towards those localities readily accessible from the newly expanding railways which provided a relatively inexpensive and convenient means of exploring the geology of the neighbourhood of Edinburgh. Charles W. Peach had a very 'hands-on' practical approach to scientific investigation which led him to construct novel glass plates with mounted Sphenopteris cuticle, removed intact from Lower Carboniferous shales and limestones originating in West Lothian. These resemble the herbarium sheets with which he was familiar from his parallel and highly significant work on extant flora including nearshore marine algae. He also prepared hand ground glass microscope slides,particularly of permineralised plant material from Pettycur in Fife, using whatever materials he had to hand at the time. Peach's collection raises questions about the evolution of accepted standards of documentation in private collections, in parallel with the evolution of collecting practices by the new professionals such as the workers of the Geological Survey. Its relatively rapid deposition in museums,compared to many private collections, may also have contributed to its apparently high rate of usage by contemporary workers