Automated real time detection of solar wind shocks and consequences for the identification of SSC and SI events

Algorithms have been developed to automatically detect Earth bound shocks in the solar wind as measured by the ACE satellite. These involve simple threshold techniques and wavelet analysis. One practical application of this shock detection is that it can provide power companies with advanced warning of the potential for geomagnetically induced currents. The automatically detected shocks have been tested against published lists of known shocks and accuracy statistics are presented. Another use for automated shock detection is an aid to the preparation of lists of rapid variations: SSC and SI events. To contribute to the IAGA published list of rapid variations, as prepared by Ebro Observatory, BGS staff routinely identify, scale and classify the events recorded at the three UK magnetic observatories. This is carried out using the criteria from the Atlas of Rapid Variations (1959) and subsequent IAGA instructions. The usefulness of automated detection of solar wind shocks for this task is examined by testing these against lists of identified SSC and SI events

Persistence and vulnerability of island endemic birds.

This thesis investigates the dynamic relationship between the processes of extinction on islands and the traits of oceanic island endemic birds associated with persistence and vulnerability. This is explored using the comparative method and a data set of all birds endemic to oceanic islands. Two case studies are then presented to examine the resilience of the island endemic birds of Principe and Boné de Joquei in the Gulf of Guinea. When comparing closely related oceanic island and mainland birds, clutch size is lower on islands and, within islands it continues to decline as the distribution area of a species decreases. Small birds (<27 cm in body length) tend to get larger, and there is a trend for sexual size dimorphism to increase on oceanic islands. Recent extinction rates are lower on islands that have been exposed to humans for a long period of time. The birds on such islands are also less threatened by the introduction of exotics. A long period of exposure to humans also reduces the probability that the remaining species are flightless, ground-nesting, or non-forest- restricted endemics. When comparing island and mainland species that have similar areas of distribution, there is no significant difference in extinction risk. However, island birds are more threatened by introduced species. On oceanic islands, flightless birds, ground-nesting birds, birds with larger body size, and habitat specialists are associated with a greater risk of extinction than other birds. Sexually selected traits such as sexual body size dimorphism and dichromatism are not associated with elevated extinction risk. The resilience of the island endemic birds on Principe appears to be associated with a unique land use history and evolutionary exposure to predators, competitors and disease. Finally, a state of super abundance may be essential for the long-term persistence of endemic birds on small remote oceanic islands.Open acces

Ising Model Coupled to Three-Dimensional Quantum Gravity

We have performed Monte Carlo simulations of the Ising model coupled to three-dimensional quantum gravity based on a summation over dynamical triangulations. These were done both in the microcanonical ensemble, with the number of points in the triangulation and the number of Ising spins fixed, and in the grand canoncal ensemble. We have investigated the two possible cases of the spins living on the vertices of the triangulation (``diect'' case) and the spins living in the middle of the tetrahedra (``dual'' case). We observed phase transitions which are probably second order, and found that the dual implementation more effectively couples the spins to the quantum gravity.Comment: 11 page

Late Pleistocene marine sediments and fossils from Mussel Roe Bay, northeastern Tasmania

Foraminifera- and mollusc-bearing estuarine sediments were encountered in one of a series of auger holes drilled in Late Pleistocene interglacial sands at Mussel Roe Bay, northeastern Tasmania. It is proposed that the estuary formed behind a bay-mouth barrier similar to that presently occurring between Mussel Roe Bay and Great Mussel Roe Bay

An Effective Model for Crumpling in Two Dimensions?

We investigate the crumpling transition for a dynamically triangulated random surface embedded in two dimensions using an effective model in which the disordering effect of the $X$ variables on the correlations of the normals is replaced by a long-range ``antiferromagnetic'' term. We compare the results from a Monte Carlo simulation with those obtained for the standard action which retains the $X$'s and discuss the nature of the phase transition.Comment: 5 page

Intra-assessor consistency in question answering

In this paper we investigate the consistency of answer assessment in a complex question answering task examining features of assessor consistency, types of answers and question type