Beyond swarm intelligence: The Ultraswarm

This paper explores the idea that it may be possible to combine two ideas – UAV flocking, and wireless cluster computing – in a single system, the UltraSwarm. The possible advantages of such a system are considered, and solutions to some of the technical problems are identified. Initial work on constructing such a system based around miniature electric helicopters is described

Buoyancy-driven dispersion in a layered porous rock

AbstractWe investigate the longitudinal dispersion of a passive tracer by a gravity-driven flow in a porous medium consisting of a series of independent horizontal layers connected to a constant pressure source. We show that in a formation of given vertical extent, the total flux is only weakly dependent on the number of layers, and is very similar to that in a single layer of the same total depth. However, although the flow speed in each layer is approximately uniform, the speed gradually increases with layer depth. As a result, if a pulse of tracer is released in the flow it will migrate more rapidly through the lower layers, leading to longitudinal dispersion of the tracer. Eventually, the location of the tracer in the different layers may become separated in space so that a sufficiently distant observation well would detect a series of discrete pulses of tracer rather than the original coherent input, as would occur in a single permeable layer. For a constant pressure source, at long times, the standard deviation of the longitudinal distribution of tracer asymptotes to a fraction of order 0.1 of the position of the centre of mass, depending on the number of layers and the overpressure of the source.This is the author accepted manuscript. The final version is available from CUP via http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9556173&fileId=S0022112014007447

Three-dimensional buoyancy-driven flow along a fractured boundary

We describe the steady motion of a buoyant fluid migrating through a porous layer along a plane, inclined boundary from a localized well. We first describe the transition from an approximately radially spreading current near the source, to a flow which runs upslope, as it spreads in the cross-slope direction. Using the model, we predict the maximum injection rate for which, near the source, the flow does not fully flood the porous layer. We then account for the presence of a fracture on the boundary through which some of the flow can drain upwards, and calculate how the current is partitioned between the fraction that drains and the remainder which continues running upslope. The fraction that drains increases with the permeability of the fracture and also with the distance from the source, as the flow slows and has more time to drain. We introduce new scalings and some asymptotic solutions to describe both the flow near the fracture and the three-dimensional surface of the injected fluid as it spreads upslope. We extend the model to the case of multiple fractures, so that the current eventually drains away as it flows over successive fractures. We calculate the shape of the region that is invaded by the buoyant fluid and we show that this flow, draining through a series of discrete fractures, may be approximated by a flow that continuously drains through its upper boundary. The effective small uniform permeability of this upper boundary is given by \textbackslash{k}_{b} \textbackslashapprox \textbackslashint \textbackslashnolimits {k}_{f} \textbackslashhspace{0.167em} \textbackslashmathrm{d} x/ {D}_{F} \textbackslash, where \textbackslash\textbackslashint \textbackslashnolimits {k}_{f} \textbackslashhspace{0.167em} \textbackslashmathrm{d} x\textbackslash is the integral of permeability across the width of the fracture and \textbackslash{D}_{F} \textbackslash is the inter-fracture spacing. Finally, we discuss the relevance of the work for CO2 sequestration and we compare some simple predictions of the plume shape, volume and volume flux derived from our model with data from the Sleipner project, Norway for the plume of CO2 which developed in Horizon 1

Fourier domain optical coherence tomography system with balance detection

A Fourier domain optical coherence tomography system with two spectrometers in balance detection is assembled using each an InGaAs linear camera. Conditions and adjustments of spectrometer parameters are presented to ensure anti-phase channeled spectrum modulation across the two cameras for a majority of wavelengths within the optical source spectrum. By blocking the signal to one of the spectrometers, the setup was used to compare the conditions of operation of a single camera with that of a balanced configuration. Using multiple layer samples, balanced detection technique is compared with techniques applied to conventional single camera setups, based on sequential deduction of averaged spectra collected with different on/off settings for the sample or reference beams. In terms of reducing the autocorrelation terms and fixed pattern noise, it is concluded that balance detection performs better than single camera techniques, is more tolerant to movement, exhibits longer term stability and can operate dynamically in real time. The cameras used exhibit larger saturation power than the power threshold where excess photon noise exceeds shot noise. Therefore, conditions to adjust the two cameras to reduce the noise when used in a balanced configuration are presented. It is shown that balance detection can reduce the noise in real time operation, in comparison with single camera configurations. However, simple deduction of an average spectrum in single camera configurations delivers less noise than the balance detection

Tales from the wild East: Traiding with Central and Eastern Europe

In the former system of trade in the countries of Central and Eastern Europe the State controlled imports and exports. Firms, both domestic and foreign, now have the potential to respond directly to local demand. The aim of the research was to identify how small firms in the South East of England who are exporting to Central and Eastern Europe, have responded to these developments. In particular the authors wanted to explore the stories respondents told about how they become involved in exporting and what their experience of this was

The Body Ontology of Capitalism

Critical social theory powerfully negates symbolic structures of political economy and imaginary projections of ideological culture but never quite knows what to do with corporeal bodies. “The Body Ontology of Capitalism” reviews Marx’s account of body ontology in his post-1859 writings (especially Capital, Vol. 1), in which value (abstract labor) is extracted from the concrete bodies of laborers caught in capital’s grasp. Body ontology is analyzed in Marx’s work as well as Lacan’s psychoanalytic social theory, exploring the relationship between structurally wounded bodies and imaginary projections. Zižek’s embodied account of wounded subjects of sublime ideological objects is also used to interpret the body fantasies of late capitalism (undead, cyborg, armored subjects). Following Marx and psychoanalytic theorists, Krier and Amidon conclude that body ontology is necessary to adequately comprehend and critique symbolic and imaginary productions of capital

Understanding mobile VLE usage in distance education: A pilot study

This paper presents preliminary results of a mobile virtual learning environment (VLE) usage study conducted at a United Kingdom (UK) based distance education institution. A total of 207 undergraduate students participated in the study over a period of 6 months. Study participants were recruited through email invitation. An online survey was conducted to gather both quantitative and qualitative data about (i) learner characteristics, (ii) awareness about the existence of the mobile VLE system, (iii) perceptions about the usefulness of using the mobile VLE system to support learning, (iv) attitudes towards using mobile VLE technological tools to support learner activities, and (v) motives for using mobile VLE tools when carrying out learning activities. Results indicate that perceived usefulness of the various technological tools incorporated in the mobile VLE system and also familiarity with their usage in teaching and learning has an effect on their deployment in distance education. These findings confirm our assumptions that the design and integration of mobile VLE in teaching and learning should be closely aligned with pedagogical goals and established practices

BioSimSpace: An interoperable Python framework for biomolecular simulation

BioSimSpace is an interoperable Python framework for biomolecular simulation. With it you can: Write robust and portable biomolecular workflow components that work on different hardware, with different software packages, and that can be run in different ways, e.g. command-line, Jupyter. Interact with molecular-simulation processes in real time

Exploration of the structural requirements of Aurora Kinase B inhibitors by a combined QSAR, modelling and molecular simulation approach

Aurora kinase B plays an important role in the cell cycle to orchestrate the mitotic process. The amplification and overexpression of this kinase have been implicated in several human malignancies. Therefore, Aurora kinase B is a potential drug target for anticancer therapies. Here, we combine atom-based 3D-QSAR analysis and pharmacophore model generation to identify the principal structural features of acylureidoindolin derivatives that could potentially be responsible for the inhibition of Aurora kinase B. The selected CoMFA and CoMSIA model showed significant results with cross-validation values (q(2)) of 0.68, 0.641 and linear regression values (r(2)) of 0.971, 0.933 respectively. These values support the statistical reliability of our model. A pharmacophore model was also generated, incorporating features of reported crystal complex structures of Aurora kinase B. The pharmacophore model was used to screen commercial databases to retrieve potential lead candidates. The resulting hits were analyzed at each stage for diversity based on the pharmacophore model, followed by molecular docking and filtering based on their interaction with active site residues and 3D-QSAR predictions. Subsequently, MD simulations and binding free energy calculations were performed to test the predictions and to characterize interactions at the molecular level. The results suggested that the identified compounds retained the interactions with binding residues. Binding energy decomposition identified residues Glu155, Trp156 and Ala157 of site B and Leu83 and Leu207 of site C as major contributors to binding affinity, complementary to 3D-QSAR results. To best of our knowledge, this is the first comparison of WaterSwap field and 3D-QSAR maps. Overall, this integrated strategy provides a basis for the development of new and potential AK-B inhibitors and is applicable to other protein targets