Challenges facing regional airport operations in Great Britain: a case study perspective of the South West of England & Wales

The deregulation of the European airline industry has had a dramatic impact on regional airports across the Union. Furthermore, the policy has changed the strategy of the so-called traditional full service network carriers, such as British Airways who as a consequence of this legislation have created powerful alliance networks and consolidated their position at fortress hubs. In comparison, low cost carriers have built a network presence around regional airports as they offer such carriers a variety of cost savings. The demise of charter airlines due to the continued fall in holiday makers booking package tours has further changed the management dynamics of regional airports. This paper examines the consequences of the above actions and evaluates how these issues have been played out within the South West of England and Wales

Microwave Transmissivity of Sub-Wavelength Metallic Structures

The use of patterned metallic surfaces for the control of the transmission of microwave radiation has been reinvigorated in recent years due to the success and interest in metamaterial research. These metallic periodic structures, commonly referred to as frequency selective screens (FSSs), allow responses to be tailored according to the geometry of the metallic structure as opposed to the material composition. A consequence of the presence of a metallic corrugation is the possible excitation of surfaces waves (commonly referred to as surface plasmon polaritons at visible frequencies). Surface waves can be utilised to achieve further control of the transmission properties of a structure. In this thesis several highly original metallic structures are investigated which use FSS and surface wave concepts. These structures exhibit interesting and previously unexplained transmission behaviour. The experimental chapters within this thesis are divided into two areas. The first three experimental chapters (4-6) present original investigations into the excitation of diffractively coupled surface waves on metallic hole/patch arrays and their role in the enhanced transmission/reflection of microwave radiation. The importance of metallic connectivity within arrays is highlighted through measurements of the metallic filling fraction dependence on the transmission properties of regular periodic and random arrays. The last two experimental chapters (7-8) contain investigations into the transmission properties of two novel resonant cavities. The structure studied in chapter 7 provides a mechanism for remarkably enhanced microwave transmission on resonance through an otherwise opaque continuous thin metal film. The second resonant cavity structure in chapter 8 uses a resonant array of metallic crosses to form a ‘resonant mirror’ Fabry-Perot cavity. These resonant FSSs exhibit a frequency dependent transmission/reflection and phase response thus producing an interesting series of modes which have very different properties to those supported by a non-resonant mirror etalon.EPSRCDst

Energy Budgets for the Caribbean Reef Coral Porites porites (Pallas)

The aim of this study was to extend the contemporary energy budget methodology for algal-cnidarian symbioses and apply it to the tropical reef coral Porites porites growing in two different environments. It was hoped that the measured energy inputs to P. porites would be equalled by the measured energy requiring processes, without a surplus or deficit of energy being determined by subtraction, and that P. porites would show a differential derivation, allocation and utilisation of energy in the two environments. Porites porites was studied at 10 m depth at both the West Fore Reef (WFR) and Columbus Park (CP) regions of Discovery Bay, Jamaica. The transmission of surface photosynthetically active radiation (PAR) to lu m depth, the temperature, sedimentation rates and nutrient levels were recorded at both sites. The CP site received less PAR, had a greater sedimentation rate and slightly enhanced nitrate concentrations compared to the WFR site. The energy budgets were calculated from measurements of photosynthesis, zooxanthellae and host respiration, zooxanthellae and host growth, colony reproduction and mucus loss. These budgets show that P. porites at both sites can be autotrophic in terms of energy on an 'ideal' day. No evidence was obtained for habitual zooplankton capture at either site. Photoadaptation at the CP site ensured that the input of photosynthetically fixed energy (PFE) was greater than at the WFR site. On an 'ideal' day at both sites 21% of the PFE was used for zooxanthellae respiration and less than 0.5% for colony reproduction whilst 26.3% (WFR site) or 6.6% (CP site) was used for host respiration and 7.1% (WFR site) or 4.3% (CP site) for zooxanthellae and host tissue growth. The loss of soluble or particulate macromolecular mucus did not account for significant amounts of energy. More than 45% of the PFE remained unaccounted for at both sites on an ideal day. A similar autotrophic status and an apparent surplus of PFE can be maintained on nearly every day of the year at both sites. In order to account for the apparent surplus energy from P. porites the colony respiration rate was compared during the day and night, the formation and energy content of mucus tunics were measured and lipid reserves determined. The colony respiration rate (representing the colony energy expenditure) increased after exposure to light and this was a function of the host tissue alone. The effect was greater at the CP site. Calcification and nutrient uptake mechanisms, and in particular the active transport of ions involved in these processes may account for the increased energy expenditure. The between-site differences in the magnitude of the elevated daytime respiration rate may represent a hitherto unrecognised cost of inhabiting the CP site. Lipid accounted for more than 18% of the dry tissue content of P. porites at both sites and supported the concept of a lipid based energy economy in corals. The daily surplus of energy can be stored as lipid in P. porites, although lipid was not metabolised during 5 days of darkness. It is suggested that lipid reserves may be important at the CP site where they could be lost as mucus during sediment shedding. Circumstantial evidence suggests that P. porites can utilise heterotrophic sources of nutrition (50 mum in size). The hypothesis that energy was periodically lost as mucus tunics was shown to be incorrect. Although tunics have a low energy content they may have an important effect in decreasing the autotrophic input by decreasing colony photosynthesis. It is suggested that the loss of low molecular weight compounds may be an alternative route for surplus energy instead of mucus. The initial objectives of the study were only partly fulfilled. Although the energy budgets showed some between site differences they were still balanced by subtraction. However, studies of lipid reserves, the daytime respiration rate and mucus tunics show that these can partially account tor the apparent surplus of energy. Further studies of the significance and mechanisms of an elevated daytime respiration rate and the role of heterotrophic nutrition in scieractinian corals will probably make a major contribution to our further understanding of the nutritional relationships in algal-cnidarian symbioses

Resonantly inverted microwave transmissivity threshold of metal grids

Open Access journal© Crown copyright 2009. This work is part funded by the Ministry of Defence and is published with the permission of the Defence Science and Technology Laboratory on behalf of the Controller of HMSO.The microwave transmission of arrays of square patches, each rotated by 45 from the axes of the square lattice on which they are positioned, has been experimentally studied as a function of metal occupancy. At low frequencies, the microwave transmissivity drops on passing through the connectivity threshold (50 per cent occupancy), as one would expect. However, quite counter-intuitively, near the onset of diffraction, resonant phenomena induce a complete reversal in the sense of this transmissivity switch, i.e. the transmission is seen to increase as the metal occupancy is increased.DstlEngineering and Physical Sciences Research Council (EPSRC

CHARTER Project Plan

At the end of CHARTER, the new repository will hold a critical mass of 4000+ digital image surrogates (and associate metadata) all with a popular culture subject theme. The 2000 new items selected for digitisation through CHARTER will have a focus on the long-nineteenth-century, 1800-1914, and will be drawn from across the University’s special collections (Bill Douglas Centre, plus Archives & Rare Books). One of the selection criteria will be that there are no IPR issues associated with these items. The 2000+ existing images transferred from EVE through CHARTER all relate to popular culture but a proportion have dates post-1914. All will be transferred to the new repository to aid their long-term preservation. As summarised in the Risk Log, there are IPR issues associated with a small proportion of these images, but these were cleared and/or have not been challenged during the 5 years the EVE facility has been available online. Evidence already exists as to the underlying quality, significance and demand for Exeter’s research collections: ‘The Bill Douglas Centre is recognised as one of the most important resources anywhere in the world […] As the numerous conferences on visual culture, Victorian studies and popular entertainment in the region attest, Devon has become the international locus for historical visualist research’ (Professor Dennis Denisoff, Ryerson University, 2007). On the strength of its collections, the Bill Douglas Centre will be submitting an application to the MLA’s Designation scheme in 2009. The testimonials in support of this application attest to the international significance of its holdings which, alongside other rare and unique special collections, CHARTER will make more widely available. The artefacts selected for digitisation from the Bill Douglas Centre and supporting special collections of archives and rare books will be chosen by an interdisciplinary team of leading academics (English, Geography, History) with a view to ensuring the critical mass of popular culture digital content captured through CHARTER has the broadest possible appeal. The original artefacts will be in a range of media (lantern slide, prints, books, stereocards, playbills, optical toys etc) which in themselves tell part of the story of the dissemination and experience of popular culture. There are three inter-related narrative themes to guide the six selection panels: Empire and Imperialism; Science, Spectacle and Magic; Work, Home and Leisure.JOINT INFORMATION SYSTEMS COMMITTEE (JISC

Microwave response of hole and patch arrays

Copyright © 2010 American Physical SocietyThe electromagnetic response of two-dimensional square arrays of perfectly conducting square patches, and their complementary structures, is modeled utilizing a modal matching technique and employing Babinet’s principle. This method allows for the introduction of progressively higher diffracted orders and waveguide modes to be included in the calculation, hence aiding understanding of the underlying causal mechanism for the observed response. At frequencies close to, but below, the onset of diffraction, a near-complete reflection condition is predicted, even for low filling fractions: conversely, for high filling fractions a near-complete transmission condition results. These resonance phenomena are associated with evanescent diffraction, which is sufficiently strong to reverse the step change in transmission upon establishment of electrical continuity; i.e., the connected structure demonstrates increased transmission with increasing filling fraction.BAE Systems Ltd.Engineering and Physical Sciences Research Council (EPSRC

Resonantly overcoming metal opacity

Copyright © 2013 American Institute of PhysicsThe near-perfect response of electrons in metals to low-frequency electromagnetic fields makes even a sub-skin-depth film almost completely opaque to microwave radiation. Here, it is experimentally demonstrated that by surrounding a ∼60 nm aluminium film with an array of thin resonant cavities, over 35% of the microwave radiation incident can be transmitted over a discrete set of narrow bands. This represents an enhancement of ∼1000 times over an isolated film and allows for a frequency selective screen with a thickness less than 1/70th of the operating wavelength that may be tuned through choice of resonant geometr

Modelling the impact of local reactive school closures on critical care provision during an influenza pandemic

Despite the fact that the 2009 H1N1 pandemic influenza strain was less severe than had been feared, both seasonal epidemics of influenza-like-illness and future influenza pandemics have the potential to place a serious burden on health services. The closure of schools has been postulated as a means of reducing transmission between children and hence reducing the number of cases at the peak of an epidemic; this is supported by the marked reduction in cases during school holidays observed across the world during the 2009 pandemic. However, a national policy of long-duration school closures could have severe economic costs. Reactive short-duration closure of schools in regions where health services are close to capacity offers a potential compromise, but it is unclear over what spatial scale and time frame closures would need to be made to be effective. Here, using detailed geographical information for England, we assess how localized school closures could alleviate the burden on hospital intensive care units (ICUs) that are reaching capacity. We show that, for a range of epidemiologically plausible assumptions, considerable local coordination of school closures is needed to achieve a substantial reduction in the number of hospitals where capacity is exceeded at the peak of the epidemic. The heterogeneity in demand per hospital ICU bed means that even widespread school closures are unlikely to have an impact on whether demand will exceed capacity for many hospitals. These results support the UK decision not to use localized school closures as a control mechanism, but have far wider international public-health implications. The spatial heterogeneities in both population density and hospital capacity that give rise to our results exist in many developed countries, while our model assumptions are sufficiently general to cover a wide range of pathogens. This leads us to believe that when a pandemic has severe implications for ICU capacity, only widespread school closures (with their associated costs and organizational challenges) are sufficient to mitigate the burden on the worst-affected hospitals