5,556 research outputs found
Modelling Basal Area of Perennial Grasses in Australian Semi-Arid Wooded Grasslands
In many semi-arid pastoral systems, landscape processes easily become dysfunctional. Shifts to less functional states may be irreversible, and have long-term consequences for pastoral profitability and social viability of rural communities. Typically, shifts to lower functional states involve a decline in perennial grasses (Hodgkinson, 1994). Here we develop a conceptual basis for modelling the basal area of perennial grasses in a semi-arid grassland and validate the model using data from a 10-year grazing study
Measuring Anomalous Couplings in H->WW* Decays at the International Linear Collider
Measurement of the Higgs coupling to W-bosons is an important test of our
understanding of the electroweak symmetry breaking mechanism. We study the
sensitivity of the International Linear Collider (ILC) to the presence of
anomalous HW+W- couplings using ZH -> nu nu WW* -> nu nu 4j events. Using an
effective Lagrangian approach, we calculate the differential decay rates of the
Higgs boson including the effects of new dimension-5 operators. We present a
Monte Carlo simulation of events at the ILC, using a full detector simulation
based on geant4 and a real event reconstruction chain. Expected constraints on
the anomalous couplings are given.Comment: 18 pages, 7 figures, 1 tabl
Modeling columnar thin films as platforms for surface-plasmonic-polaritonic optical sensing
Via exploitation of surface plasmon polaritons (SPPs), columnar thin films
(CTFs) are attractive potential platforms for optical sensing as their relative
permittivity dyadic and porosity can be tailored to order. Nanoscale model
parameters of a CTF were determined from its measured relative permittivity
dyadic, after inverting the Bruggeman homogenization formalism. These model
parameters were then used to determine the relative permittivity dyadic of a
fluid-infiltrated CTF. Two boundary-value problems were next solved: the first
relating to SPP-wave propagation guided by the planar interface of a
semi-infinitely thick metal and a semi-infinitely thick CTF, and the second to
the plane-wave response of the planar interface of a finitely thick metallic
layer and a CTF in a modified Kretschmann configuration. Numerical studies
revealed that SPP waves propagate at a lower phase speed and with a shorter
propagation length, if the fluid has a larger refractive index. Furthermore,
the angle of incidence required to excite an SPP wave in a modified Kretschmann
configuration increases as the refractive index of the fluid increases
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