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  • Journal article
    Tsarouchi GM, Buytaert W, Mijic A, 2014,

    Coupling a land-surface model with a crop growth model to improve ET flux estimations in the Upper Ganges basin, India

    , Hydrol. Earth Syst. Sci., Vol: 18, Pages: 4223-4238
  • Journal article
    Kelly NJ, Tuohy PG, Hawkes AD, 2014,

    Performance assessment of tariff-based air source heat pump load shifting in a UK detached dwelling featuring phase change-enhanced buffering

    , APPLIED THERMAL ENGINEERING, Vol: 71, Pages: 809-820, ISSN: 1359-4311
  • Journal article
    St John FAV, Keane AM, Jones JPG, Milner-Gulland EJet al., 2014,

    Robust study design is as important on the social as it is on the ecological side of applied ecological research

    , Journal of Applied Ecology, ISSN: 1365-2664

    1. The effective management of natural systems often requires resource users to change their behaviour. This has led to many applied ecologists using research tools developed by social scientists. This comes with challenges as ecologists often lack relevant disciplinary training.2. Using an example from the current issue of Journal of Applied Ecology that investigated how conservation interventions influenced conservation outcomes, we discuss the challenges of conducting interdisciplinary science. We illustrate our points using examples from research investigating the role of law enforcement and outreach activities in limiting illegal poaching and the application of the theory of planned behaviour to conservation.3. Synthesis and applications. Interdisciplinary research requires equal rigour to be applied to ecological and social aspects. Researchers with a natural science background need to access expertise and training in the principles of social science research design and methodology, in order to permit a more balanced interdisciplinary understanding of social–ecological systems.
  • Journal article
    Kelley DI, Harrison SP, Prentice IC, 2014,

    Improved simulation of fire-vegetation interactions in the Land surface Processes and eXchanges dynamic global vegetation model (LPX-Mv1)

    , Geoscientific Model Development, Vol: 7, Pages: 2411-2433, ISSN: 1991-959X

    The Land surface Processes and eXchanges (LPX) model is a fire-enabled dynamic global vegetation model that performs well globally but has problems representing fire regimes and vegetative mix in savannas. Here we focus on improving the fire module. To improve the representation of ignitions, we introduced a reatment of lightning that allows the fraction of ground strikes to vary spatially and seasonally, realistically partitions strike distribution between wet and dry days, and varies the number of dry days with strikes. Fuel availability and moisture content were improved by implementing decomposition rates specific to individual plant functional types and litter classes, and litter drying rates driven by atmospheric water content. To improve water extraction by grasses, we use realistic plant-specific treatments of deep roots. To improve fire responses, we introduced adaptive bark thickness and post-fire resprouting for tropical and temperate broadleaf trees. All improvements are based on extensive analyses of relevant observational data sets. We test model performance for Australia, first evaluating parameterisations separately and then measuring overall behaviour against standard benchmarks. Changes to the lightning parameterisation produce a more realistic simulation of fires in southeastern and central Australia. Implementation of PFT-specific decomposition rates enhances performance in central Australia. Changes in fuel drying improve fire in northern Australia, while changes in rooting depth produce a more realistic simulation of fuel availability and structure in central and northern Australia. The introduction of adaptive bark thickness and resprouting produces more realistic fire regimes in Australian savannas. We also show that the model simulates biomass recovery rates consistent with observations from several different regions of the world characterised by resprouting vegetation. The new model (LPX-Mv1) produces an improved simulation of observed vege
  • Journal article
    Manap N, Voulvoulis N, 2014,

    Risk-based decision-making framework for the selection of sediment dredging option

    , SCIENCE OF THE TOTAL ENVIRONMENT, Vol: 496, Pages: 607-623, ISSN: 0048-9697
  • Journal article
    Anandarajah G, Gambhir A, 2014,

    India's CO<sub>2</sub> emission pathways to 2050: What role can renewables play?

    , APPLIED ENERGY, Vol: 131, Pages: 79-86, ISSN: 0306-2619
  • Journal article
    Credgington D, Liu S-W, Nelson J, Durrant JRet al., 2014,

    In Situ Measurement of Energy Level Shifts and Recombination Rates in Subphthalocyanine/C<sub>60</sub> Bilayer Solar Cells

    , JOURNAL OF PHYSICAL CHEMISTRY C, Vol: 118, Pages: 22858-22864, ISSN: 1932-7447
  • Journal article
    Foster S, Deledalle F, Mitani A, Kimura T, Kim K-B, Okachi T, Kirchartz T, Oguma J, Miyake K, Durrant JR, Doi S, Nelson Jet al., 2014,

    Electron Collection as a Limit to Polymer:PCBM Solar Cell Efficiency: Effect of Blend Microstructure on Carrier Mobility and Device Performance in PTB7:PCBM

    , ADVANCED ENERGY MATERIALS, Vol: 4, ISSN: 1614-6832
  • Journal article
    Carrasco LR, Larrosa C, Milner-Gulland EJ, Edwards DPet al., 2014,

    A double-edged sword for tropical forests

    , SCIENCE, Vol: 346, Pages: 38-40, ISSN: 0036-8075
  • Journal article
    Jacobs CT, Avdis A, Gorman GJ, Piggott MDet al., 2014,

    PyRDM: A Python-based Library for Automating the Management and Online Publication of Scientific Software and Data

    , Journal of Open Research Software, Vol: 2, ISSN: 2049-9647
  • Journal article
    Zhou S, Medlyn B, Sabate S, Sperlich D, Prentice ICet al., 2014,

    Short-term water stress impacts on stomatal, mesophyll and biochemical limitations to photosynthesis differ consistently among tree species from contrasting climates

    , Tree Physiology, Vol: 34, Pages: 1035-1046, ISSN: 1758-4469

    Predicting the large-scale consequences of drought in contrasting environments requires that we understand how drought effects differ among species originating from those environments. A previous meta-analysis of published experiments suggested that the effects of drought on both stomatal and non-stomatal limitations to photosynthesis may vary consistently among species from different hydroclimates. Here, we explicitly tested this hypothesis with two short-term water stress experiments on congeneric mesic and xeric species. One experiment was run in Australia using Eucalyptus species and the second was run in Spain using Quercus species as well as two more mesic species. In each experiment, plants were grown under moist conditions in a glasshouse, then deprived of water, and gas exchange was monitored. The stomatal response was analysed with a recently developed stomatal model, whose single parameter g1 represents the slope of the relationship between stomatal conductance and photosynthesis. The non-stomatal response was partitioned into effects on mesophyll conductance (gm), the maximum Rubisco activity (Vcmax) and the maximum electron transport rate (Jmax). We found consistency among the drought responses of g1, gm, Vcmax and Jmax, suggesting that drought imposes limitations on Rubisco activity and RuBP regeneration capacity concurrently with declines in stomatal and mesophyll conductance. Within each experiment, the more xeric species showed relatively high g1 under moist conditions, low drought sensitivity of g1, gm, Vcmax and Jmax, and more negative values of the critical pre-dawn water potential at which Vcmax declines most steeply, compared with the more mesic species. These results indicate adaptive interspecific differences in drought responses that allow xeric tree species to continue transpiration and photosynthesis for longer during periods without rain.
  • Journal article
    Zhao M, Shi J, Zhong X, Tian S, Blamey J, Jiang J, Fennell PSet al., 2014,

    A novel calcium looping absorbent incorporated with polymorphic spacers for hydrogen production and CO2 capture

    , Energy and Environmental Science, Vol: 7, Pages: 3291-3295, ISSN: 1754-5692

    High temperature looping cycles can be used to produce hydrogen or capture CO2 from power stations, though sintering of absorbents is frequently a problem, reducing reactivity. In this work we develop materials, in which the crystal structure and volume of polymorphic materials change with temperature, as active spacers to reduce sintering.
  • Journal article
    Le Vine SE, Lee-Gosselin MEH, Sivakumar A, Polak JWet al., 2014,

    A new approach to predict the market and impacts of round-trip and point-to-point carsharing systems: case study of London

    , Transportation Research Part D: Transport and Environment, Vol: 32, Pages: 218-229, ISSN: 1361-9209

    There are nearly two million subscribers to carsharing services worldwide. These services can provide large benefits both to users and the general public (e.g. through emissions reductions). There has not however previously existed a general framework for forecasting their market potential and impacts that is sensitive to the way that they re-structure the costs associated with personal car ownership. Techniques for predicting market scope and impacts ahead of field implementation are urgently required, both by entrepreneurs and the public sector, whose support, or at least acquiescence, is generally required.This paper draws on the Perceived Activity Set conceptual framework that was recently developed to address the methodological challenges posed by carsharing, and presents the first set of empirical findings from employing it to model carsharing. The empirical analysis makes uses of pooled data from the British National Travel Survey and a purpose-designed stated-choice survey. We investigate both the ‘round-trip’ and ‘point-to-point’ carsharing service models.The results suggest that the number of prospective subscribers to a point-to-point carsharing service in London is between three and four times as large as the comparable number for round-trip carsharing. The greatest reduction in overall vehicle-miles of travel – including both carsharing cars and private cars – was found from introducing round-trip carsharing across all of London. Survey respondents indicated they would use point-to-point carsharing for commuting journeys much more frequently than round-trip carsharing. Finally, point-to-point carsharing was found to be a substitute for public transport, whilst round-trip carsharing was found to be a complement.
  • Conference paper
    Howey DA, Yufit V, Mitcheson PD, Offer GJ, Brandon NPet al., 2014,

    Impedance measurement for advanced battery management systems

    We present a fast, low-cost approach to measure battery impedance 'on-line' in a vehicle across a range of frequencies (1-2000 Hz). Impedance measurement has promise for improving battery management since it is a very effective non-invasive method of diagnosing the internal state of an electrochemical cell. It is useful for estimating temperature, ageing, state of charge (SOC) and for fault detection. The aim of this paper is firstly to explore the usefulness of impedance for estimating SOC, focusing on lithium-ion iron phosphate (LFP) and nickel manganese cobalt oxide (NMC) cells, and secondly to demonstrate the performance of a low cost impedance measurement system that uses an existing motor drive similar to that of an electric vehicle to excite the battery current. We find that measurements made with this system are accurate to within a few per cent of results from an expensive, bulky commercial system. For SOC estimation in NMC cells, the charge transfer resistance and SEI layer resistance vary significantly with SOC. In LFP cells the parameter variation is much less obvious, although the double layer capacitance of the full pack may be a useful indicator of SOC.
  • Conference paper
    Mazur C, Contestabile M, Offer GJ, Brandon NPet al., 2014,

    Understanding the automotive industry: German OEM behaviour during the last 20 years and its implications

    This work presents a study of how the automotive industry has responded in the last 20 years to pressures driven by economic and environmental issues, and by the transition towards electric mobility. Timelines for the major German automotive OEMs are presented to understand the industry's behaviour in the past in order to design suitable policies that are appropriate to reach future goals around the electrification of road transport. Based upon a comparison of the pressures arising in the automotive sector and the companies' behaviour with regard to technology choice and R&D, a set of hypotheses concerning this behaviour is then presented.
  • Journal article
    Yu W, Xu L, Graham N, Qu Jet al., 2014,

    Pre-treatment for ultrafiltration: effect of pre-chlorination on membrane fouling

    , SCIENTIFIC REPORTS, Vol: 4, ISSN: 2045-2322
  • Journal article
    Strbac G, Pollitt M, Konstantinidis CV, Konstantelos I, Moreno R, Newbery D, Green Ret al., 2014,

    Electricity transmission arrangements in Great Britain: Time for change?

    , Energy Policy, Vol: 73, Pages: 298-311, ISSN: 0301-4215

    In Great Britain (GB) and across Europe significant investment in electricity transmission is expected over the coming years as decarbonisation and market integration efforts are intensified. However, there is also significant uncertainty with the amount, location and timing of new generation connection, which in turn will drive the transmission investment needs. Given the absence of efficient market design, we identify three key areas of concern with the current transmission investment arrangements: (i) a mis-aligned incentives framework for transmission investment and operation; (ii) lack of coordination of investment and operation; and (iii) conflicts of interest. We then propose three options for future evolution of transmission regimes, which cover the full spectrum of institutional arrangements with respect to transmission planning and delivery, i.e. how and who plans, owns, builds and operates the transmission system. For each option we present: key characteristics; evolution of the current regimes; the ability of the option to address the concerns; and key strengths and weaknesses. Overall, we conclude in the case of GB (this conclusion could be extended to other European countries) that the most appropriate option would be that of an Independent System Operator (ISO) who would be responsible for planning and operating the transmission system.
  • Journal article
    Hey J, Teo TJ, Viet PB, Yang G, Martinez-Botas Ret al., 2014,

    Electromagnetic actuator design analysis using a two-stage optimization method with coarse-fine model output space mapping

    , IEEE Transactions on Industrial Electronics, Vol: 61, Pages: 5453-5464, ISSN: 0278-0046

    Electromagnetic actuators are energy conversion devices that suffer from inefficiencies. The conversion losses generate internal heat, which is undesirable, as it leads to thermal loading on the device. Temperature rise should be limited to enhance the reliability, minimize thermal disturbance, and improve the output performance of the device. This paper presents the application of an optimization method to determine the geometric configuration of a flexure-based linear electromagnetic actuator that maximizes output force per unit of heat generated. A two-stage optimization method is used to search for a global solution, followed by a feasible solution locally using a branch and bound method. The finite element magnetic (fine) model is replaced by an analytical (coarse) model during optimization using an output space mapping technique. An 80% reduction in computation time is achieved by the application of such an approximation technique. The measured output from the new prototype based on the optimal design shows a 45% increase in air gap magnetic flux density, a 40% increase in output force, and a 26% reduction in heat generation when compared with the initial design before application of the optimization method.
  • Conference paper
    Offer GJ, Plant DJ, Silversides RW, Smith TMS, Goodwill R, Kanabar P, Martinez-Botas RFet al., 2014,

    Control and energy management strategies for a novel series hybrid

    In this work a novel series hybrid powertrain concept is presented. The concept removes the requirement for a power electronic converter to manage the state of charge of the accumulators by controlling the power flow between the generator and accumulator. Instead, the engine and generator are directly coupled and the state of charge of the accumulators is maintained by controlling the speed and power output of the engine to control the power flow to the accumulators. Results are presented from a proof-of-concept system that was built for a vehicle with a target peak power of 60kW with supercapacitors. Models are also presented comparing and contrasting a battery version with the supercapacitor version for a Formula Student vehicle. The powertrain is particularly suited for applications which have very high torque requirements, and hence the use of a mechanical gearbox introduces significant cost & weight, and is also ideally suited for applications where power needs to be distributed throughout an application to multiple locations, and hence multiple mechanical linkages would normally be required. The supercapacitor version is most suited to applications with high peak to average load ratios and noisy load cycles, and the battery version could be seen as a low cost route to range extend a battery electric vehicle.
  • Journal article
    Hey J, Kiew CM, Yang G, Martinez-Botas Ret al., 2014,

    Model-Based Compensation of Thermal Disturbance in a Precision Linear Electromagnetic Actuator

    , IEEE-ASME TRANSACTIONS ON MECHATRONICS, Vol: 19, Pages: 1477-1488, ISSN: 1083-4435
  • Journal article
    Milner-Gulland EJ, Mcgregor JA, Agarwala M, Atkinson G, Bevan P, Clements T, Daw T, Homewood K, Kumpel N, Lewis J, Mourato S, Fry BP, Redshaw M, Rowcliffe JM, Suon S, Wallace G, Washington H, Wilkie Det al., 2014,

    Accounting for the Impact of Conservation on Human Well-Being

    , CONSERVATION BIOLOGY, Vol: 28, Pages: 1160-1166, ISSN: 0888-8892
  • Journal article
    Dani KGS, Jamie IM, Prentice IC, Atwell BJet al., 2014,

    Increased Ratio of Electron Transport to Net Assimilation Rate Supports Elevated Isoprenoid Emission Rate in Eucalypts under Drought

    , PLANT PHYSIOLOGY, Vol: 166, Pages: 1059-1072, ISSN: 0032-0889
  • Journal article
    Montrikittiphant T, Tang M, Lee K-Y, Williams CK, Bismarck Aet al., 2014,

    Bacterial Cellulose Nanopaper as Reinforcement for Polylactide Composites: Renewable Thermoplastic NanoPaPreg

    , MACROMOLECULAR RAPID COMMUNICATIONS, Vol: 35, Pages: 1640-1645, ISSN: 1022-1336
  • Journal article
    Didham RK, Ewers RM, 2014,

    Edge Effects Disrupt Vertical Stratification of Microclimate in a Temperate Forest Canopy

    , PACIFIC SCIENCE, Vol: 68, Pages: 493-508, ISSN: 0030-8870
  • Journal article
    Gray C, Baird DJ, Baumgartner S, Jacob U, Jenkins GB, O'Gorman EJ, Lu X, Ma A, Pocock MJO, Schuwirth N, Thompson M, Woodward Get al., 2014,

    FORUM Ecological networks: the missing links in biomonitoring science

    , JOURNAL OF APPLIED ECOLOGY, Vol: 51, Pages: 1444-1449, ISSN: 0021-8901
  • Report
    Gross R, Speirs J, Hawkes AD, Skillings S, Heptonstall Pet al., 2014,

    Could retaining old coal lead to a policy own goal?
  • Journal article
    Montrikittiphant T, Tang M, Lee KY, Williams CK, Bismarck Aet al., 2014,

    Macromol. Rapid commun. 19/2014.

    , Macromol Rapid Commun, Vol: 35

    Frontispiece: A Werkstoffverbund (laminated composite) manufacturing concept is used to produce high performance renewable bacterial cellulose (BC) nanopaper reinforced thermoplastic laminates. The mechanical performance of the resulting BC-reinforced thermoplastic laminates is found to be dependent on the tensile performance of the reinforcing BC nanopaper. Further details can be found in the article by T. Montrikittiphant, M. Tang, K.-Y. Lee,* C. K. Williams, and A. Bismarck* on page 1640.
  • Journal article
    Khan AE, Scheelbeek PFD, Shilpi AB, Chan Q, Mojumder SK, Rahman A, Haines A, Vineis Pet al., 2014,

    Salinity in drinking water and the risk of (pre)eclampsia and gestational hypertension in coastal Bangladesh: A case-control study

    , PLoS One, Vol: 9, Pages: 1-9, ISSN: 1932-6203

    BackgroundHypertensive disorders in pregnancy are among the leading causes of maternal and perinatal death in low-income countries, but the aetiology remains unclear. We investigated the relationship between salinity in drinking water and the risk of (pre)eclampsia and gestational hypertension in a coastal community.MethodsA population-based case-control study was conducted in Dacope, Bangladesh among 202 pregnant women with (pre)eclampsia or gestational hypertension, enrolled from the community served by the Upazilla Health Complex, Dacope and 1,006 matched controls from the same area. Epidemiological and clinical data were obtained from all participants. Urinary sodium and sodium levels in drinking water were measured. Logistic regression was used to calculate odds ratios, and 95% confidence intervals.FindingsDrinking water sources had exceptionally high sodium levels (mean 516.6 mg/L, S.D 524.2). Women consuming tube-well (groundwater) were at a higher disease risk than rainwater users (p<0.001). Adjusted risks for (pre)eclampsia and gestational hypertension considered together increased in a dose-response manner for increasing sodium concentrations (300.01–600 mg/L, 600.1–900 mg/L, >900.01 mg/L, compared to <300 mg/L) in drinking water (ORs 3.30 [95% CI 2.00–5.51], 4.40 [2.70–7.25] and 5.48 [3.30–9.11] (p-trend<0.001). Significant associations were seen for both (pre)eclampsia and gestational hypertension separately.InterpretationSalinity in drinking water is associated with increased risk of (pre)eclampsia and gestational hypertension in this population. Given that coastal populations in countries such as Bangladesh are confronted with high salinity exposure, which is predicted to further increase as a result of sea level rise and other environmental influences, it is imperative to develop and evaluate affordable approaches to providing water with low salt content.
  • Journal article
    Cotter CJ, McRae ATT, 2014,

    Compatible finite element methods for numerical weather prediction

    , Proceedings of the EMCWF Annual Seminar

    This article takes the form of a tutorial on the use of a particular class ofmixed finite element methods, which can be thought of as the finite elementextension of the C-grid staggered finite difference method. The class is oftenreferred to as compatible finite elements, mimetic finite elements, discretedifferential forms or finite element exterior calculus. We provide anelementary introduction in the case of the one-dimensional wave equation,before summarising recent results in applications to the rotating shallow waterequations on the sphere, before taking an outlook towards applications inthree-dimensional compressible dynamical cores.
  • Journal article
    Kirchartz T, Nelson J, 2014,

    Device Modelling of Organic Bulk Heterojunction Solar Cells

    , MULTISCALE MODELLING OF ORGANIC AND HYBRID PHOTOVOLTAICS, Vol: 352, Pages: 279-324, ISSN: 0340-1022

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