Characteristics of Food Expenditures in Argentina: Implications for the U.S. Dairy Industry

This Discussion Paper provides an analysis of the structure of Argentine dairy and non-dairy food expenditures using a series of econometric models.Argentine Dairy Industry, Econometric Models, Demand and Price Analysis, International Development, Production Economics,

The Basic Formula Price: Has the Use of NASS Cheese Prices Changed Its Value?

Agribusiness, Demand and Price Analysis,

A Modern Approach to Regression with R

Abstracts not available for BookReview

Graph colouring for office blocks

The increasing prevalence of WLAN (wireless networks) introduces the potential of electronic information leakage from one company's territory in an office block, to others due to the long-ranged nature of such communications. BAE Systems have developed a system ('stealthy wallpaper') which can block a single frequency range from being transmitted through a treated wall or ceiling to the neighbour. The problem posed to the Study Group was to investigate the maximum number of frequencies ensure the building is secure. The Study group found that this upper bound does not exist, so they were asked to find what are "good design-rules" so that an upper limit exists

Rabbit Warrens of South-West England: Landscape Context, Socio-Economic Significance and Symbolism

For several centuries following their introduction into the British Isles by the Normans, rabbits were farmed on man-made warrens. The right to hunt rabbits during the medieval period was restricted to the highest strata of society and warrens, and rabbit products, carried connotations of wealth and exclusivity. During the post-medieval period, as rabbits became less expensive, their exclusivity declined and access to the species increased across a wider spread of the population. Consequently, later warrens tended to be purely commercial ventures that in places lingered as a form of animal husbandry up until the early twentieth century. Evidence of these warrens is particularly common across England and Wales and typically, although not exclusively, takes the form of pillow mounds, earthworks created to encourage rabbits to burrow. Despite their longevity and high numbers, warrens remain relatively little studied. This thesis investigates surviving warren architecture within south-west England, incorporating archaeological data into a GIS in order to identify the locational, morphological and typological trends of the region’s warrens. It also assesses associations between warrens and other classes of archaeology, notably elite residences and parks, large ecclesiastical institutions and prehistoric earthworks. Doing so allows for a better understanding of warrens’ roles within their immediate environs and of their relationships with other aspects of the human landscape. This study also addresses natural geographical aspects of the landscape in order to determine the principal factors that influenced where warrens were installed. This study investigates documentary reference to warrens as many have not survived within the landscape. Medieval chancery rolls in particular allow for the creation of a national framework of warrening so that the South West can be compared and contrasted to other regions of medieval England. Documentary references, both medieval and post-medieval, to the South West’s warrens allow for the creation of a discrete regional history that defines the context for the establishment of the region’s warren architecture. This study assesses how rabbits were interpreted by medieval society and discusses symbolism, particularly the visual role played by warrens in advertising their owners’ wealth and any possible religious concepts associated with rabbits

Open Innovation and Stakeholder Engagement

The paradox of open innovation lies in the conflict between the practical desire to reap the benefits of open innovation and concern over the risk that others will misappropriate those benefits. Stakeholder theory and recent developments in value creation through stakeholder engagement can assist with reconciliation of this inherent structural risk. The limitations of existing open innovation typologies are identified, and a process-based model of open innovation is proposed. The model is then expanded to include stakeholder engagement. When integrated with stakeholder engagement, open innovation processes can be understood to generate benefits beyond the acquisition of specific information sought from external experts. The addition of stakeholder engagement to the open innovation model allows for greater understanding and easier acceptance of the risks inherent in the open innovation process

Studies of the electrical properties and electroforming of thin insulating films

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Evaporated thin film sandwich structures of Au-SiOX-Au have been studied. These normally show electroforming effects and subsequently electron emission, electroluminescence, negative resistance and thermal-voltage memory effects. Previous work in the field is critically reviewed. It was shown that the time dependence of the device current and emission current can be explained by making certain modifications to the filamentary conduction theory of Dearnaley. Detailed direct current-voltage measurements have revealed the existence of two different types of breakdown behaviour. At voltages less than 20 V single-hole breakdowns were observed, while in the voltage range 20-30 V large scale irreversible breakdown behaviour took place. The dependence of the voltage at which this occurs (Vß) on insulator thickness and temperature, together with measurements of the device temperature at breakdown and visual evidence of damage after breakdown, has led to the conclusion that this type of breakdown is a thermal effect. Such measurements also pointed to the existence of a high field region within the insulator, and potential distribution measurements confirmed this hypothesis. The high field region was also in evidence at low temperatures where the device current (Ic) showed a log Ic α Vb1/2 dependence on applied voltage (Vb). Measurements of electron attenuation lengths in SiOx gave values of 400-1000 Å irrespective of temperature. The temperature independence was consistent with the emitted electron energy distributions at 77 and 300 K. It was shown that electrons underwent Bragg diffraction through the top Au electrode. The angular distribution of emitted electrons became more isotropic with increasing voltage. Measurements on other systems showed that Al-SiOx/B2O3-Al devices could withstand very high voltages and give improved emission efficiency, while Au-CaBr2-Au and Au-Si3N4-Au devices showed very high initial currents and current-voltage characteristics which were irreversible

On the Completeness of Reflex Astrometry on Extrasolar Planets near the Sensitivity Limit

We provide a preliminary estimate of the performance of reflex astrometry on Earth-like planets in the habitable zones of nearby stars. In Monte Carlo experiments, we analyze large samples of astrometric data sets with low to moderate signal-to-noise ratios. We treat the idealized case of a single planet orbiting a single star, and assume there are no non-Keplerian complications or uncertainties. The real case can only be more difficult. We use periodograms for discovery and least-squares fits for estimating the Keplerian parameters. We find a completeness for detection compatible with estimates in the literature. We find mass estimation by least squares to be biased, as has been found for noisy radial-velocity data sets; this bias degrades the completeness of accurate mass estimation. When we compare the true planetary position with the position predicted from the fitted orbital parameters, at future times, we find low completeness for an accuracy goal of 0.3 times the semimajor axis of the planet, even with no delay following the end of astrometric observations. Our findings suggest that the recommendation of the ExoPlanet Task Force (Lunine et al. 2008) for "the capability to measure convincingly wobble semi-amplitudes down to 0.2 $\mu$as integrated over the mission lifetime," may not be satisfied by an instrument characterized by the noise floor of the Space Interferometry Mission, $\sigma_\mathrm{floor}\approx0.035\mu$as. An important, unsolved, strategic challenge for the exoplanetary science program is figuring out how to predict the future position of an Earth-like planet with accuracy sufficient to ensure the efficiency and success of the science operations for follow-on spectroscopy, which would search for biologically significant molecules in the atmosphere.Comment: v2: 16 pages, 4 figures; ApJ accepte