Now showing items 60-79 of 299

  • Depletion of nonlinearity in the pressure force driving Navier-Stokes flows : nonlinear depletion in NS flows 

    Tran, Chuong Van; Yu, Xinwei (2015-04-17) - Journal article
    The dynamics of the velocity norms ||u||Lq for q ≥ 3, in Navier-Stokes flows is studied. The pressure term that drives this dynamics has a high degree of nonlinear depletion, which owes its origin to a genuine negative ...
  • Description and seasonal detection of two potential whale calls recorded in the Indian Ocean 

    Sousa, Andreia G; Harris, Danielle (2015-09) - Journal article
    Unidentified acoustic signals are recorded by hydrophones placed in the world's oceans. Some of these sounds are suspected to originate from marine mammals. In this study, two acoustic signals recorded by two arrays at ...
  • Design and analysis of line transect surveys for primates 

    Buckland, Stephen Terrence; Plumptre, A J; Thomas, Len; Rexstad, Eric A (2010-10) - Journal article
    Line transect surveys are widely used for estimating abundance of primate populations. The method relies on a small number of key assumptions, and if these are not met, substantial bias may occur. For a variety of reasons, ...
  • Digit frequencies and Bernoulli convolutions 

    Kempton, Thomas Michael William (2014-06-27) - Journal article
    It is well known that when β is a Pisot number, the corresponding Bernoulli convolution ν(β) has Hausdorff dimension less than 1, i.e. that there exists a set A(β) with (ν(β))(A(β))=1 and dim_H(A(β))<1. We show explicitly ...
  • Dimension and measure for generic continuous images 

    Balka, Richard; Farkas, Abel; Fraser, Jonathan M.; Hyde, James T. (2013) - Journal article
    We consider the Banach space consisting of continuous functions from an arbitrary uncountable compact metric space, X, into R-n. The key question is 'what is the generic dimension of f(X)?' and we consider two different ...
  • Dimension conservation for self-similar sets and fractal percolation 

    Falconer, Kenneth John; Jin, Xiong (2015) - Journal article
    We introduce a technique that uses projection properties of fractal percolation to establish dimension conservation results for sections of deterministic self-similar sets. For example, let K be a self-similar subset of ...
  • Distance software: design and analysis of distance sampling surveys for estimating population size 

    Thomas, Len; Buckland, Stephen Terrence; Rexstad, Eric; Laake, J L; Strindberg, S; Hedley, S L; Bishop, J R B; Marques, Tiago Andre Lamas Oliveira (2010) - Journal article
    1. Distance sampling is a widely used technique for estimating the size or density of biological populations. Many distance sampling designs and most analyses use the software Distance. 2. We briefly review distance sampling ...
  • Double-observer line transect methods : levels of independence 

    Buckland, Stephen Terrence; Laake, Jeffrey L.; Borchers, David Louis (2010-03) - Journal article
    Double-observer line transect methods are becoming increasingly widespread, especially for the estimation of marine mammal abundance from aerial and shipboard surveys when detection of animals on the line is uncertain. The ...
  • Double-observer line transect surveys with Markov-modulated Poisson process models for overdispersed animal availability 

    Borchers, David Louis; Langrock, Roland (2015-12) - Journal article
    We develop maximum likelihood methods for line transect surveys in which animals go undetected at distance zero, either because they are stochastically unavailable while within view or because they are missed when they are ...
  • A dynamical definition of f.g. virtually free groups 

    Bennett, Daniel; Bleak, Collin (2016-02) - Journal article
    We show that the class of finitely generated virtually free groups is precisely the class of demonstrable subgroups for R. Thompson's group V . The class of demonstrable groups for V consists of all groups which can embed ...
  • Dynamical patterns of coexisting strategies in a hybrid discrete-continuum spatial evolutionary game model 

    Burgess, A. E. F; Schofield, P. G.; Hubbard, S. F.; Chaplain, Mark A. J.; Lorenzi, T. (2016-12-07) - Journal article
    We present a novel hybrid modelling framework that takes into account two aspects which have been largely neglected in previous models of spatial evolutionary games: random motion and chemotaxis. A stochastic individual-based ...
  • Effect of collisions on amplification of laser beams by Brillouin scattering in plasmas 

    Humphrey, K. A.; Trines, R. M. G. M.; Fiuza, F.; Speirs, D. C.; Norreys, P.; Cairns, R. A.; Silva, L. O.; Bingham, R. (2013-10) - Journal article
    We report on particle in cell simulations of energy transfer between a laser pump beam and a counter-propagating seed beam using the Brillouin scattering process in uniform plasma including collisions. The results presented ...
  • Effect of Prandtl's ration on balance in geophysical turbulence 

    Dritschel, David Gerard; McKiver, William Joseph (2015-07-21) - Journal article
    The fluid dynamics of the atmosphere and oceans are to a large extent controlled by the slow evolution of a scalar field called ‘potential vorticity’, with relatively fast motions such as inertia-gravity waves playing only ...
  • Effects of a scientific echo sounder on the behavior of short-finned pilot whales (Globicephala macrorhynchus) 

    Quick, Nicola; Scott-Hayward, Lindesay; Sadykova, Dinara; Nowacek, Doug; Read, Andrew (2016-09-26) - Journal article
    Active echo sounding devices are often employed for commercial or scientific purposes in the foraging habitats of marine mammals. We conducted an experiment off Cape Hatteras, North Carolina, USA, to assess whether the ...
  • An efficient acoustic density estimation method with human detectors applied to gibbons in Cambodia 

    Kidney, Darren; Rawson, Benjamin M.; Borchers, David Louis; Stevenson, Ben; Marques, Tiago A.; Thomas, Len (2016-05-19) - Journal article
    Some animal species are hard to see but easy to hear. Standard visual methods for estimating population density for such species are often ineffective or inefficient, but methods based on passive acoustics show more promise. ...
  • Ellipsoidal vortices in rotating stratified fluids : beyond the quasi-geostrophic approximation 

    Tsang, Yue-Kin; Dritschel, David G. (2015-01) - Journal article
    We examine the basic properties and stability of isolated vortices having uniform potential vorticity (PV) in a non-hydrostatic rotating stratified fluid, under the Boussinesq approximation. For simplicity, we consider a ...
  • Embeddings into Thompson's group V and coCF groups 

    Bleak, Collin; Matucci, Francesco; Neunhöffer, Max (2016-10) - Journal article
    It is shown in Lehnert and Schweitzer (‘The co-word problem for the Higman–Thompson group is context-free’, Bull. London Math. Soc. 39 (2007) 235–241) that R. Thompson's group V is a co-context-free (coCF) group, thus ...
  • Emergence of non-twisted magnetic fields in the Sun : jets and atmospheric response 

    Syntelis, P.; Archontis, V.; Gontikakis, C.; Tsinganos, K. (2015-12) - Journal article
    Aims. We study the emergence of a non-twisted flux tube from the solar interior into the solar atmosphere. We investigate whether the length of the buoyant part of the flux tube (i.e. λ) affects the emergence of the field ...
  • Ends of semigroups 

    Craik, S.; Gray, R.; Kilibarda, V.; Mitchell, J. D.; Ruskuc, N. (2016-10) - Journal article
    We define the notion of the partial order of ends of the Cayley graph of a semigroup. We prove that the structure of the ends of a semigroup is invariant under change of finite generating set and at the same time is inherited ...
  • Estimability of variance components when all model matrices commute 

    Bailey, Rosemary Anne; Ferreira, Sandra S.; Ferreira, Dario; Nunes, Celia (2016-03-01) - Journal article
    This paper deals with estimability of variance components in mixed models when all model matrices commute. In this situation, it is well known that the best linear unbiased estimators of fixed effects are the ordinary least ...