Now showing items 105-124 of 328

  • Estimates of past and future ozone trends from multi-model simulations using a flexible smoothing spline methodology 

    Scinocca, John F.; Stephenson, David B.; Bailey, Trevor C.; Austin, John (American Geophysical Union, 2010)
    A novel additive model analysis of multimodel trends is presented. The approach is motivated by, and particularly suited to, the analysis of multimodel time series of varying length. This Time series Additive Model (TSAM) ...
  • The evaluation of directionally writhing polymers 

    Prior, C.B.; Berger, M.A. (arXiv.org, 2010)
    We discuss the appropriate techniques for modelling the geometry of open ended elastic polymer molecules. The molecule is assumed to have fixed endpoints on a boundary surface. In particular we discuss the concept of the ...
  • Event collisions in systems with delayed switches 

    Sieber, J.; Kowalczyk, P. (Elsevier, 2006)
    We study dynamical systems that switch between two different vector fields depending on a discrete variable. If the two vector fields have linearly unstable fixed points and the switch is subject to a hysteresis and to a ...
  • The evolution of connectivity in metabolic networks. 

    Pfeiffer, Thomas; Soyer, Orkun S.; Bonhoeffer, Sebastian (Public Library of Science, 2005)
    Processes in living cells are the result of interactions between biochemical compounds in highly complex biochemical networks. It is a major challenge in biology to understand causes and consequences of the specific design ...
  • Evolution of Kelvin-Helmholtz activity on the dusk flank magnetopause 

    Foullon, Claire; Farrugia, Charles J.; Fazakerley, Andrew; Owen, Christopher J.; Gratton, F.T.; Torbert, R.B. (American Geophysical Union (AGU), 2008)
    Our purpose is to characterize the evolution of the magnetopause Kelvin-Helmholtz (KH) wave activity with changes in thickness of the adjacent boundary layer, geomagnetic latitude and interplanetary magnetic field (IMF) ...
  • Evolution of response dynamics underlying bacterial chemotaxis 

    Soyer, Orkun S.; Goldstein, Richard A. (BioMed Central, 2011)
    Background: The ability to predict the function and structure of complex molecular mechanisms underlying cellular behaviour is one of the main aims of systems biology. To achieve it, we need to understand the evolutionary ...
  • Evolution of spiral and scroll waves of excitation in a mathematical model of ischaemic border zone 

    Biktashev, V. N.; Biktasheva, I. V.; Sarvazyan, N. A. (Public Library of Science, 2011)
    Abnormal electrical activity from the boundaries of ischemic cardiac tissue is recognized as one of the major causes in generation of ischemia-reperfusion arrhythmias. Here we present theoretical analysis of the waves of ...
  • Evolution of taxis responses in virtual bacteria: non-adaptive dynamics. 

    Goldstein, Richard A.; Soyer, Orkun S. (Public Library of Science, 2008)
    Bacteria are able to sense and respond to a variety of external stimuli, with responses that vary from stimuli to stimuli and from species to species. The best-understood is chemotaxis in the model organism Escherichia ...
  • Evolution of the L1 halo family in the radial solar sail circular restricted three-body problem 

    Verrier, Patricia; Waters, Thomas; Sieber, J. (Springer Verlag, 2014)
    We present a detailed investigation of the dramatic changes that occur in the L1 halo family when radiation pressure is introduced into the Sun–Earth circular restricted three-body problem (CRTBP). This photo-gravitational ...
  • The evolution of writhe in kink-unstable flux ropes and erupting filaments 

    Torok, T.; Kliem, B.; Berger, M.A.; Linton, M.G.; Demoulin, P.; van Driel-Gesztelyi, L. (IOP Publishing, 2014)
    The helical kink instability of a twisted magnetic flux tube has been suggested as a trigger mechanism for solar filament eruptions and coronal mass ejections (CMEs). In order to investigate if estimations of the pre-emptive ...
  • Evolution under Fluctuating Environments Explains Observed Robustness in Metabolic Networks 

    Soyer, Orkun S.; Pfeiffer, Thomas (Public Library of Science, 2010)
    A high level of robustness against gene deletion is observed in many organisms. However, it is still not clear which biochemical features underline this robustness and how these are acquired during evolution. One hypothesis, ...
  • Evolving Bayesian Emulators for Structured Chaotic Time Series, with application to large climate models 

    Williamson, Daniel; Blaker, Adam T. (Society for Industrial and Applied Mathematics and American Statistical Association, 2014)
    We develop Bayesian dynamic linear model Gaussian processes for emulation of time series output for computer models that may exhibit chaotic behavior, but where this behavior retains some underlying structure. The statistical ...
  • Excitability in ramped systems: the compost-bomb instability 

    Wieczorek, Sebastian; Ashwin, Peter; Luke, Catherine M.; Cox, Peter M. (Royal Society, 2011)
    The paper studies a novel excitability type where a large excitable response appears when a system’s parameter is varied gradually, or ramped, above some critical rate. This occurs even though there is a (unique) stable ...
  • Exospheric models for the X-ray emission from single Wolf-Rayet stars 

    Ignace, R.; Oskinova, L.M.; Foullon, Claire (Oxford University Press / Royal Astronomical Society, 2000)
    We review existing ROSAT detections of single Galactic Wolf-Rayet (WR) stars and develop wind models to interpret the X-ray emission. The ROSAT data, consisting of bandpass detections from the ROSAT All-Sky Survey (RASS) ...
  • Experimental Comparison of Classification Uncertainty for Randomised and Bayesian Decision Tree Ensembles 

    Schetinin, Vitaly; Partridge, Derek; Krzanowski, Wojtek J.; Everson, Richard M.; Fieldsend, Jonathan E.; Bailey, Trevor C.; Hernandez, Adolfo (Springer Berlin Heidelberg, 2004)
    In this paper we experimentally compare the classification uncertainty of the randomised Decision Tree (DT) ensemble technique and the Bayesian DT technique with a restarting strategy on a synthetic dataset as well as on ...
  • Explicit integral Galois module structure of weakly ramified extensions of local fields 

    Johnston, Henri (American Mathematical Society, 2015)
    Let L/K be a finite Galois extension of complete local fields with finite residue fields and let G=Gal(L/K). Let G_1 and G_2 be the first and second ramification groups. Thus L/K is tamely ramified when G_1 is trivial and ...
  • Explicit representation of subgrid heterogeneity in a GCM land surface scheme 

    Essery, R. L. H.; Best, M. J.; Betts, R. A.; Cox, Peter M.; Taylor, Christopher M. (American Meteorological Society, 2003)
    A land surface scheme that may be run with or without a tiled representation of subgrid heterogeneity and includes an implicit atmospheric coupling scheme is described. Simulated average surface air temperatures and diurnal ...
  • Exploratory ensemble designs for environmental models using k-extended Latin Hypercubes 

    Williamson, Daniel (Wiley, 2015)
    In this paper we present a novel, flexible, and multi-purpose class of designs for initial exploration of the parameter spaces of computer models, such as those used to study many features of the environment. The idea ...
  • Exploring links between Arctic amplification and mid-latitude weather 

    Screen, James A.; Simmonds, Ian (American Geophysical Union, 2013)
    This study examines observed changes (1979–2011) in atmospheric planetary-wave amplitude over northern mid-latitudes, which have been proposed as a possible mechanism linking Arctic amplification and mid-latitude weather ...
  • Exponential integrators for a Markov chain model of the fast sodium channel of cardiomyocytes. 

    Stary, T.; Biktashev, V. N. (Institute of Electrical and Electronics Engineers (IEEE), 2015)
    The modern Markov chain models of ionic channels in excitable membranes are numerically stiff. The popular numerical methods for these models require very small time steps to ensure stability. Our objective is to formulate ...