1,372 research outputs found

    Operational and research aspects of a radio-controlled model flight test program

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    The operational and research aspects of a subscale, radio-controlled model flight test program are presented. By using low-cost free-flying models, an approach was developed for obtaining research-quality vehicle performance and aerodynamic information. The advantages and limitations learned by applying this approach to a specific flight test program are described. The research quality of the data acquired shows that model flight testing is practical for obtaining consistent and repeatable flight data

    An empirical investigation into the changing visual identity of full service and low cost carriers, 2000 vs. 2012

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    Purpose: This paper reports on the findings of an analysis of the visual branding of over 630 airline tail fins as they appeared in 2000 and 2012. Design/methodology: Unlike existing studies of airlines’ visual identities that rely on a snap shot in time and examine all airlines, this paper focuses on changes that have occurred in the visual branding of full-service carriers (FSCs) and low cost carriers (LCCs) between 2000 and 2012 using a semiotic content analysis. Findings: The results confirm that there have been significant changes in the visual content of FSC and LCC tail fins and the way in which these airlines portray non-price competitive characteristics. The research shows that while an increasing number of LCCs now use aircraft tail fins to display their corporate name, FSCs are increasingly employing icons of nationhood. This suggests that while LCCs are trying to appeal to a wide passenger demographic who value low fares over service, FSCs are responding to the competitive threat by explicitly drawing on the cultural rhetoric of symbols of sovereign national identity to differentiate themselves in an increasingly competitive market. Originality/value: This paper builds on previous analyses of this type focusing on temporal comparisons and suggesting differing strategies adopted by LCCs and FSCs.Peer Reviewe

    Caves and Karst of West-Central Florida

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    Analysing the financial performance of US hub airports in relation to lease agreement types

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    This paper performs a cluster analysis to examine the financial implications of the different types of airline lease agreements used by U.S. hub airports. Four key financial performance indicators relating to financial profitability including revenue generation, capital investment, commercial performance and cost effectiveness are analysed using 2011/12 financial data for large-hub airports. The results show that while financial performance varies according to traffic mix, airports with the same agreement types are clustered together. The paper concludes by noting that airports’ control of their financial performance varies by agreement type and the identified clusters support the subcategorisation of airport performance indicators

    A Monte-Carlo approach to estimating the effects of selected airport capacity options in London

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    The issue of future airport capacity in London is currently the subject of much political debate in the UK. Although realistic estimates of the effects of capacity enhancement may be desirable, such estimates are difficult. Through the use of Monte Carlo simulation, this paper quantifies and compares the relative capacity enhancements that may be afforded by the construction of a new hub airport in the Thames Estuary, additional runways at Heathrow, Gatwick and Stansted and changes to operating practices at Heathrow. The simulations show that a new hub airport would be the most effective way to increase capacity, although the reported financial and environmental costs of such a development indicate a comparatively poor rate of return. Proposed new runways at Heathrow, Gatwick and Stansted and the removal of runway alternation at Heathrow provide more modest increases in capacity

    Aeronautical charging policy incentive schemes for airlines at European airports

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    This paper introduces the concept of incentive schemes that may accompany airports’ aeronautical charging policies and develops a taxonomy of such schemes based on an analysis of data for 46 European Airports held in the RDC Aviation database.1 This taxonomy details the different types of incentive schemes that in are operation. It is clear their use is widespread and that the magnitude of the incentive is often significant. A financial benchmarking analysis is undertaken for four selected airports to illustrate the extent of the variations between airports both in terms of the basic characteristics of the incentive schemes and in the periods over which the discounts are available

    The quantitative genetics of incipient speciation: Heritability and genetic correlations of skeletal traits in populations of diverging favia fragum ecomorphs

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    Recent speciation events provide potential opportunities to understand the microevolution of reproductive isolation. We used a marker-based approach and a common garden to estimate the additive genetic variation in skeletal traits in a system of two ecomorphs within the coral species Favia fragum: a Tall ecomorph that is a seagrass specialist, and a Short ecomorph that is most abundant on coral reefs. Considering both ecomorphs, we found significant narrow-sense heritability (h 2) in a suite of measurements that define corallite architecture, and could partition additive and nonadditive variation for some traits. We found positive genetic correlations for homologous height and length measurements among different types of vertical plates (costosepta) within corallites, but negative correlations between height and length within, as well as between costosepta. Within ecomorphs, h 2 estimates were generally lower, compared to the combined ecomorph analysis. Marker-based estimates of h 2 were comparable to broad-sense heritability (H) obtained from parent-offspring regressions in a common garden for most traits, and similar genetic co-variance matrices for common garden and wild populations may indicate relatively small G × E interactions. The patterns of additive genetic variation in this system invite hypotheses of divergent selection or genetic drift as potential evolutionary drivers of reproductive isolation. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution
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