Gravity gradient preliminary investigations on exhibit ''A'' Final report

Quartz microbalance gravity gradiometer performance test

The social side of Homo economicus

Many recent experiments in the field of behavioural economics appear to demonstrate a willingness of humans to behave altruistically, even when it is not in their interest to do so. This has led to the assertion that humans have evolved a special predisposition towards altruism. Recent studies have questioned this, and demonstrated that selfless cooperation does not hold up in controlled experiments. As I discuss here, this calls for more economic 'field experiments' and highlights the need for greater integration of the evolutionary and economic sciences

Improved laboratory gradiometer can be a field survey instrument

Improvements made to quartz gradiometer minimize or eliminate disturbing effects from known error sources and permit sensitivity of + or - 1 times 10 to the minus 9th power/sec sq or better and measuring accuracy of + or - 5 times 10 to the minus 9th power/sec sq

Aspects of the breeding biology of wading birds (charadrii) on a saltmarsh

Aspects of the breeding biology of Lapwing, Oyster- catcher and Redshank were studied on a dry, cattle-grazed saltmarsh, Rockcliffe Marsh, in Cumbria. The vegetation of the marsh was predominantly graminoid, due to the influence of grazing and trampling by cattle. There was a halosere from the landward Lolio-cynosuretum to the seaward Puccinellietum. Invertebrate abundance and biomass declined across the halosere, as did grazing intensity, which was indicated by cowpat density. Cowpat density was positively correlated with the abundance and biomass of Diptera and total invertebrates. The proportion of dung-associated invertebrates varied across the halosere, but over 80% of Diptera in each vegetation type were dung-associated. The proportion of eggs plus chicks of each species which was trampled was positively correlated with cowpat density, indicating that cowpat density was a valid measure of grazing intensity. Each wader species nested at a higher than average cowpat density where the mean cowpat density was low, to maximise food availability, and at a lower than average cowpat density where the mean cowpat density was high, to minimise the risk of trampling. Lapwing nest density was positively correlated with cowpat density (proximate factor) and total invertebrate biomass (ultimate factor). The main prey of adult and chick waders were dung-associated invertebrates. The proximate factors involved in breeding area and nest-site selection by the fore-mentioned wader species and Dunlin and Ringed Plover were elucidated by a multivariate comparison of nest and non-nest samples. The proximate factors were typically related to those features associated with a grazed habitat, e.g. tussock abundance, cowpat density, and with the avoidance of inundation, e.g. distance to nearest creek and plateau edges. The proximate and ultimate factors were discussed with reference to their implications for breeding wader habitat management

Four Stokes parameter radio frequency polarimetry of a flare from AD Leonis

Observations of the four Stokes parameters of a 430 MHz flare from the UV Ceti-type star AD Leonis are presented. The maximum amplitude of the event was 0.52 flux units and the durations at one-half and one-tenth maximum were 12 and 40 seconds, respectively. The degree of circular polarization at maximum intensity was approximately 56 percent and was later observed to be as high as 92 percent. Linear polarization was also observed at a level of about 21 percent at flare maximum which allowed an upper limit of 440 radians - sq m to be placed on the rotation measure

Validation of DIRSIG, an infrared synthetic scene generation model

A validation and sensitivity study was performed in which the accuracy of an infrared synthetic image generation model (DIRSIG) was examined. The majority of the error in the model is derived from two major programs: a temperature predictor and a radiative transfer model. A thermodynamic model computes kinetic temperatures of objects in a computer generated three-dimensional scene. These temperatures, atmospheric data, and sensor parameters are used as input to a ray_tracer which models the propagation of radiation in a source-target-sensor path within this scene. The output is a simulated infrared image which a sensor with the given input parameters would record. The accuracy of the model and the impact of uncertainties in individual input variables were determined by error propagation methods and comparison of the simulated imagery with actual imagery. The average theoretical error in radiance reaching the sensor was determined to be 1.58 W/m2-sr, while the measured average error in radiance for an actual predicted scene was determined to be 2.98 W/m2-sr (13.99%). Variables which had the greatest impact on the final predictive error of the model were identified and ranked accordingly. In addition, problem areas within the model were identified and suggestions for improvement were made