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  • Journal article
    Tavares G, Parpas P, 2013,

    On the information-based complexity of stochastic programming

    , OPERATIONS RESEARCH LETTERS, Vol: 41, Pages: 622-626, ISSN: 0167-6377
  • Journal article
    Tang M, Purcell M, Steele JAM, Lee K-Y, McCullen S, Shakesheff KM, Bismarck A, Stevens MM, Howdle SM, Williams CKet al., 2013,

    Porous Copolymers of ε-Caprolactone as Scaffolds for Tissue Engineering

    , MACROMOLECULES, Vol: 46, Pages: 8136-8143, ISSN: 0024-9297
  • Journal article
    Michael NA, Whittaker AC, Allen PA, 2013,

    The functioning of sediment routing systems using a mass balance approach: Example from the Eocene of the southern Pyrenees

    , Journal of Geology, Vol: 121, Pages: 581-606
  • Journal article
    Rosa IMD, Purves D, Souza C, Ewers RMet al., 2013,

    Predictive modelling of contagious deforestation in the brazilian amazon

    , PLOS One, Vol: 8, ISSN: 1932-6203

    <p>Tropical forests are diminishing in extent due primarily to the rapid expansion of agriculture, but the future magnitude and geographical distribution of future tropical deforestation is uncertain. Here, we introduce a dynamic and spatially-explicit model of deforestation that predicts the potential magnitude and spatial pattern of Amazon deforestation. Our model differs from previous models in three ways: (1) it is probabilistic and quantifies uncertainty around predictions and parameters; (2) the overall deforestation rate emerges “bottom up”, as the sum of local-scale deforestation driven by local processes; and (3) deforestation is contagious, such that local deforestation rate increases through time if adjacent locations are deforested. For the scenarios evaluated–pre- and post-PPCDAM (“Plano de Ação para Proteção e Controle do Desmatamento na Amazônia”)–the parameter estimates confirmed that forests near roads and already deforested areas are significantly more likely to be deforested in the near future and less likely in protected areas. Validation tests showed that our model correctly predicted the magnitude and spatial pattern of deforestation that accumulates over time, but that there is very high uncertainty surrounding the exact sequence in which pixels are deforested. The model predicts that under pre-PPCDAM (assuming no change in parameter values due to, for example, changes in government policy), annual deforestation rates would halve between 2050 compared to 2002, although this partly reflects reliance on a static map of the road network. Consistent with other models, under the pre-PPCDAM scenario, states in the south and east of the Brazilian Amazon have a high predicted probability of losing nearly all forest outside of protected areas by 2050. This pattern is less strong in the post-PPCDAM scenario. Contagious spread along roads and through areas lacking formal protecti

  • Journal article
    Siegert M, Ross N, Corr H, Kingslake J, Hindmarsh Ret al., 2013,

    Late Holocene ice-flow reconfiguration in the Weddell Sea sector of West Antarctica

    , Quaternary Science Reviews, Vol: 78, Pages: 98-107, ISSN: 0277-3791

    Here we report Late Holocene ice sheet and grounding-line changes to the Weddell Sea sector of West Antarctica. Internal radio-echo layering within the Bungenstock Ice Rise, which comprises very slow-flowing ice separating the fast-flowing Institute and Möller ice streams, reveals ice deformed by former enhanced flow, overlain by un-deformed ice. The ice-rise surface is traversed by surface lineations explicable as diffuse ice-flow generated stripes, which thus capture the direction of flow immediately prior to the creation of the ice rise. The arrangement of internal layers can be explained by adjustment to the flow path of the Institute Ice Stream, during either a phase of ice sheet retreat not longer than ∼4000 years ago or by wholesale expansion of the grounding-line from an already retreated situation not sooner than ∼400 years ago. Some combination of these events, involving uplift of the ice rise bed during ice stream retreat and reorganisation, is also possible. Whichever the case, the implication is that the ice sheet upstream of the Bungenstock Ice Rise, which currently grounds over a >1.5 km deep basin has been, and therefore may be, susceptible to significant change.

  • Patent
    Offer GJ, Plant DJ, Silversides RA, 2013,

    A Drive Train for a Hybrid Electric Vehicle and a Method of Operating Such a Drive Train

    , WO2012146891 A3

    A method of operating a drive train (110) for a hybrid electric vehicle, and a drive train, is disclosed. The drive train comprises an internal combustion engine (120), a first electrical machine (130) and electrical energy storage means (150). The internal combustion engine is coupled to drive the first electrical machine as a generator and the first electrical machine connected to supply electrical energy to the electrical energy storage means. The electrical energy storage means is arranged for supplying electrical energy to at least a second electrical machine (170) for driving wheels (180) of a hybrid electric vehicle. The method comprises the steps of sensing a parameter indicative of the voltage across the electrical energy storage means and, in response to this sensed parameter, controlling the internal combustion engine and/or the first electrical machine such that the first electrical machine operates to give rise to a voltage output of the first electrical machine such that the electrical energy storage means is charged without the need for power electronics.

  • Journal article
    Hylton NP, Li XF, Giannini V, Lee K-H, Ekins-Daukes NJ, Loo J, Vercruysse D, Van Dorpe P, Sodabanlu H, Sugiyama M, Maier SAet al., 2013,

    Loss mitigation in plasmonic solar cells: aluminium nanoparticles for broadband photocurrent enhancements in GaAs photodiodes

    , SCIENTIFIC REPORTS, Vol: 3, ISSN: 2045-2322
  • Journal article
    Cooper SJ, Kishimoto M, Tariq F, Bradley RS, Marquis AJ, Brandon NP, Kilner JA, Shearing PRet al., 2013,

    Microstructural Analysis of an LSCF Cathode Using In Situ Tomography and Simulation

    , ECS Transactions, Vol: 57, Pages: 2671-2678, ISSN: 1938-6737

    Electrode tortuosity factor is a key input parameter in many fuel cell simulations. Three-dimensional microstructural data obtained from in-situ synchrotron X-ray nano-computed tomography is used as the basis for comparing five approaches to quantify the tortuosity factor. Three of these techniques are based on diffusivity simulations and showed strong correlation, but had consistently different absolute values. A random walk method showed a good degree of correlation to the diffusive approaches, but had the largest values overall. Lastly, a calculation that used a mean pore centroid approach showed little correlation to any of the other three methods, but compared well with the conventional Bruggeman correlation. Due to the diffusive nature of the ionic transport in electrodes, the authors would recommend calculating tortuosity factors using a diffusive approach based on the voxels rather than a remeshed volume.

  • Journal article
    Ryan JW, Kirchartz T, Viterisi A, Nelson J, Palomares Eet al., 2013,

    Understanding the Effect of Donor Layer Thickness and a MoO<sub>3</sub> Hole Transport Layer on the Open-Circuit Voltage in Squaraine/C<sub>60</sub> Bilayer Solar Cells

    , JOURNAL OF PHYSICAL CHEMISTRY C, Vol: 117, Pages: 19866-19874, ISSN: 1932-7447
  • Journal article
    Bruno A, Reynolds LX, Dyer-Snaith C, Nelson J, Haque SAet al., 2013,

    Determining the Exciton Diffusion Length in a Polyfluorene from Ultrafast Fluorescence Measurements of Polymer/Fullerene Blend Films

    , JOURNAL OF PHYSICAL CHEMISTRY C, Vol: 117, Pages: 19832-19838, ISSN: 1932-7447
  • Journal article
    Candelise C, Winskel M, Gross R, 2013,

    The dynamics of solar PV costs and prices as a challenge for technology forecasting

    , Renewable and Sustainable Energy Reviews, Vol: 26, Pages: 96-107
  • Journal article
    Veraart AED, 2013,

    Stationary and multi-self-similar random fields with stochastic volatility

    , Stochastics, Vol: 87, Pages: 848-870, ISSN: 0090-9491

    This paper introduces stationary and multi-self-similar random fields which account for stochastic volatility and have type G marginal law. The stationary random fields are constructed using volatility modulated mixed moving average (MA) fields and their probabilistic properties are discussed. Also, two methods for parameterizing the weightfunctions in the MA representation are presented: one method is based on Fourier techniques and aims at reproducing a given correlation structure, the other method is based on ideas from stochastic partial differential equations. Moreover, using a generalized Lamperti transform we construct volatility modulated multi-self-similar random fields which have type G distribution.

  • Report
    Green RJ, 2013,

    The Future Role of Energy in Manufacturing

    , London, Publisher: Government Office for Science

    This report considers the present and future role of energy in manufacturing, in the context of the need to deliver a low-carbon economy. That need presents two threats to UK-based manufacturers, and two opportunities. The first threat is that the price of energy in the UK will rise, compared to the cost faced by competitor firms abroad, placing UK manufacturers at a significant disadvantage. The second threat is that a low-carbon electricity supply will be unreliable, and that the cost of power cuts will rise. The first opportunity is related to this threat – manufacturing sites that can reduce their electricity imports at times when the power system is under stress are already paid for doing so. The need for such demand-side management, the options for providing it, and the price paid are all likely to increase over time. The second opportunity is that new low-carbon products will be needed – not least in the transport sector – and UK-based firms may be able to break into these new markets.

  • Journal article
    Morgan JV, Warner MR, Bell R, Ashley J, Barnes D, Little R, Roele K, Jones Cet al., 2013,

    Next-generation seismic experiments: wide-angle, multi-azimuth,three-dimensional, full-waveform inversion

    , Geophysical Journal International, Vol: in press

    Full-waveform inversion (FWI) is an advanced seismic imaging technique that has recentlybecome computationally feasible in three dimensions, and that is being widely adopted andapplied by the oil and gas industry. Here we explore the potential for 3-D FWI, when combinedwith appropriate marine seismic acquisition, to recover high-resolution high-fidelity P-wavevelocity models for subsedimentary targets within the crystalline crust and uppermost mantle.We demonstrate that FWI is able to recover detailed 3-D structural information within aradially faulted dome using a field data set acquired with a standard 3-D petroleum-industrymarine acquisition system. Acquiring low-frequency seismic data is important for successfulFWI; we show that current acquisition techniques can routinely acquire field data from airgunsat frequencies as low as 2 Hz, and that 1 Hz acquisition is likely to be achievable using oceanbottomhydrophones in deep water. Using existing geological and geophysical models, weconstruct P-wave velocity models over three potential subsedimentary targets: the Soufri`ereHills Volcano on Montserrat and its associated crustal magmatic system, the crust and uppermostmantle across the continent–ocean transition beneath the Campos Basin offshore Brazil,and the oceanic crust and uppermost mantle beneath the East Pacific Rise mid-ocean ridge.Weuse these models to generate realistic multi-azimuth 3-D synthetic seismic data, and attempt toinvert these data to recover the original models.We explore resolution and accuracy, sensitivityto noise and acquisition geometry, ability to invert elastic data using acoustic inversion codes,and the trade-off between low frequencies and starting velocity model accuracy.We show thatFWI applied to multi-azimuth, refracted, wide-angle, low-frequency data can resolve featuresin the deep crust and uppermost mantle on scales that are significantly better than can beachieved by any other geophysical technique, and that these results ca

  • Journal article
    Jonker HJJ, van Reeuwijk M, Sullivan PP, Patton EGet al., 2013,

    On the scaling of shear-driven entrainment: a DNS study

    , Journal of Fluid Mechanics, Vol: 732, Pages: 150-165, ISSN: 0022-1120

    The deepening of a shear-driven turbulent layer penetrating into stably stratified quiescent layer is studied using Direct Numerical Simulation (DNS). The simulation design mimics the classical laboratory experiments by Kato and Phillips (J. Fluid Mech. 37, 643–655, 1969) in that it starts with linear stratification and applies a constant shear stress at the lower boundary, but avoids inherent side wall and rotation effects of that experiment. It is found that the layers universally deepen as a function of the square root of time, independent of the initial stratification and the Reynolds number of the simulations, provided that the Reynolds number is large enough. Consistent with this finding, the dimensionless entrainment velocity varies with the bulk Richardson number as Ri−1/2 . In addition it is observed that all cases evolve in a self-similar fashion. A selfsimilarity analysis of the conservation equations shows that only a square root growth law is consistent with self-similar behaviour.

  • Journal article
    Raaschou-Nielsen O, Vineis P, Brunekreef B, Nieuwenhuijsen M, Mann BH, Forastiere F, Oudin A, Hoek G, Katsouyanni K, Schwarze P, Beelen Ret al., 2013,

    Air pollution and lung cancer in Europe Reply

    , LANCET ONCOLOGY, Vol: 14, Pages: E440-E440, ISSN: 1470-2045
  • Journal article
    Wielicki BA, Young DF, Mlynczak MG, Thome KJ, Leroy S, Corliss J, Anderson JG, Ao CO, Bantges R, Best F, Bowman K, Brindley H, Butler JJ, Collins W, Dykema JA, Doelling DR, Feldman DR, Fox N, Huang X, Holz R, Huang Y, Jin Z, Jennings D, Johnson DG, Jucks K, Kato S, Kirk-Davidoff DB, Knuteson R, Kopp G, Kratz DP, Liu X, Lukashin C, Mannucci AJ, Phojanamongkolkij N, Pilewskie P, Ramaswam V, Revercomb YH, Rice J, Roberts Y, Roithmayr CM, Rose F, Sandford S, Shirley EL, Smith WL, Soden SB, Speth PW, Sun W, Taylor PC, Tobin D, Xiong Xet al., 2013,

    Achieving Climate Change Absolute Accuracy in Orbit

    , BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, Vol: 94, Pages: 1519-1539, ISSN: 0003-0007
  • Journal article
    Robert M Ewers DCR, 2013,

    Using landscape history to predict biodiversity patterns in fragmented landscapes

    , Ecology Letters, Vol: 16, Pages: 1221-1233, ISSN: 1461-023X

    Landscape ecology plays a vital role in understanding the impacts of land-use change on biodiversity, but it is not a predictive discipline, lacking theoretical models that quantitatively predict biodiversity patterns from first principles. Here, we draw heavily on ideas from phylogenetics to fill this gap, basing our approach on the insight that habitat fragments have a shared history. We develop a landscape ‘terrageny’, which represents the historical spatial separation of habitat fragments in the same way that a phylogeny represents evolutionary divergence among species. Combining a random sampling model with a terrageny generates numerical predictions about the expected proportion of species shared between any two fragments, the locations of locally endemic species, and the number of species that have been driven locally extinct. The model predicts that community similarity declines with terragenetic distance, and that local endemics are more likely to be found in terragenetically distinctive fragments than in large fragments. We derive equations to quantify the variance around predictions, and show that ignoring the spatial structure of fragmented landscapes leads to over-estimates of local extinction rates at the landscape scale. We argue that ignoring the shared history of habitat fragments limits our ability to understand biodiversity changes in human-modified landscapes.

  • Journal article
    Lari KS, van Reeuwijk M, Maksimovic C, 2013,

    The role of geometry in rough wall turbulent mass transfer (vol 49, pg 1191, 2013)

    , HEAT AND MASS TRANSFER, Vol: 49, Pages: 1523-1523, ISSN: 0947-7411
  • Journal article
    Ayala P, Cantizano A, Gutierrez-Montes C, Rein Get al., 2013,

    Influence of atrium roof geometries on the numerical predictions of fire tests under natural ventilation conditions

    , ENERGY AND BUILDINGS, Vol: 65, Pages: 382-390, ISSN: 0378-7788
  • Journal article
    de Nazelle A, Aguilera I, Nieuwenhuijsen M, Beelen R, Cirach M, Hoek G, de Hoogh K, Sunyer J, Targa J, Brunekreef B, Kuenzli N, Basagana Xet al., 2013,

    Comparison of performance of land use regression models derived for Catalunya, Spain

    , ATMOSPHERIC ENVIRONMENT, Vol: 77, Pages: 598-606, ISSN: 1352-2310
  • Journal article
    Ragettli MS, Corradi E, Braun-Faehrlaender C, Schindler C, de Nazelle A, Jerrett M, Ducret-Stich RE, Kuenzli N, Phuleria HCet al., 2013,

    Commuter exposure to ultrafine particles in different urban locations, transportation modes and routes

    , ATMOSPHERIC ENVIRONMENT, Vol: 77, Pages: 376-384, ISSN: 1352-2310
  • Journal article
    Bal N, Rein G, 2013,

    Relevant model complexity for non-charring polymer pyrolysis

    , FIRE SAFETY JOURNAL, Vol: 61, Pages: 36-44, ISSN: 0379-7112
  • Journal article
    Barndorff-Nielsen OE, Benth FE, Pedersen J, Veraart AEDet al., 2013,

    On stochastic integration for volatility modulated Levy-driven Volterra processes

    , Stochastic Processes and Their Applications, Vol: n/a, ISSN: 0304-4149
  • Book
    Helffrich G, Wookey J, Bastow I, 2013,

    The Seismic Analysis Code

    , Publisher: Cambridge University Press, ISBN: 9781107045453

    The first comprehensive guide to SAC, complete with introductory materials and detailed descriptions of its most advanced features.

  • Journal article
    Morfopoulos C, Prentice IC, Keenan TF, Friedlingstein P, Medlyn BE, Penuelas J, Possell Met al., 2013,

    A unifying conceptual model for the environmental responses of isoprene emissions from plants

    , ANNALS OF BOTANY, Vol: 112, Pages: 1223-1238, ISSN: 0305-7364

    Background and AimsIsoprene is the most important volatile organic compound emitted by land plants in terms ofabundance and environmental effects. Controls on isoprene emission rates include light, temperature, water supplyand CO2concentration. A need to quantify these controls has long been recognized. There are already models thatgive realistic results, but they are complex, highly empirical and require separate responses to different drivers.This study sets out to find a simpler, unifying principle.†MethodsA simple model is presented based on the idea of balancing demands for reducing power (derived fromphotosynthetic electron transport) in primary metabolism versus the secondary pathway that leads to the synthesisof isoprene. This model’s ability to account for key features in a variety of experimental data sets is assessed.†Key resultsThe model simultaneously predicts the fundamental responses observed in short-term experiments,namely: (1) the decoupling between carbon assimilation and isoprene emission; (2) a continued increase in isopreneemission with photosynthetically active radiation (PAR) at high PAR, after carbon assimilation has saturated; (3) amaximum of isoprene emission at low internal CO2concentration (ci) and an asymptotic decline thereafter with in-creasingci; (4) maintenance of high isoprene emissions when carbon assimilation is restricted by drought; and (5) atemperature optimum higher than that of photosynthesis, but lower than that of isoprene synthase activity.†ConclusionsA simple model was used to test the hypothesisthat reducing poweravailable to the synthesis pathwayfor isoprene varies according to the extent to which the needs of carbon assimilation are satisfied. Despite its simpli-city the model explains much in terms of the observed response of isoprene to external drivers as well asthe observeddecoupling between carbon assimilation and isoprene emission. The concept has the potential to improve global-scale

  • Journal article
    Blasing TJ, Sullivan A, Madani K, 2013,

    Response of California Summer Hydroelectricity Generation to Spring Temperature

    , British Journal of Environment and Climate Change, Vol: 3, Pages: 316-332
  • Journal article
    Berloff P, Kamenkovich I, 2013,

    On spectral analysis of mesoscale eddies. Part II: Nonlinear analysis.

    , Journal of Physical Oceanography, Vol: n/a, ISSN: 0022-3670
  • Journal article
    Graven HD, Keeling RF, Piper SC, Patra PK, Stephens BB, Wofsy SC, Welp LR, Sweeney C, Tans PP, Kelley JJ, Daube BC, Kort EA, Santoni GW, Bent JDet al., 2013,

    Enhanced Seasonal Exchange of CO<sub>2</sub> by Northern Ecosystems Since 1960

    , SCIENCE, Vol: 341, Pages: 1085-1089, ISSN: 0036-8075
  • Conference paper
    Wilson DJ, Crocket KC, van de Flierdt T, Robinson LF, Adkins JFet al., 2013,

    Deglacial ocean circulation variability in the Northwest Atlantic Ocean from neodymium isotopes and radiocarbon in deep-sea corals

    , 11th International Conference on Paleoceanography

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