On the free energy of a directed polymer in a Brownian environment

We prove a formula conjectured in O'Connell and Yor (2001) for the free energy density of a directed polymer in a Brownian environment in 1+1 dimensions.Comment: 15 pages. To appear in Markov Processes and Related Filelds (J.T. Lewis special edition

Air transport in Africa: toward sustainable business models for African airlines

Although there is a vast amount of literature on airline business models and their evolution in changing global landscapes, there is a general lack of research into the applicability of those models, traditionally defined in European and North American contexts, to the African scene. Implicit in this study is the hypothesis that the African environment is unique enough to warrant its own host of strategies, which may be distinctive enough to form part of a new strategic template, or business model. Initially, a review of existing literature is undertaken to profile the African aviation environment and evaluate existing airline business models and their evolution, both globally and in Africa. The methodology consists firstly of a cluster exercise, whereby 57 African airlines are analysed in terms of their network and size, to yield a number of heterogeneous groups which serve to identify the current business models of airlines on the continent. Following this, eight airlines (representative of the groups outlined in the cluster analysis) were subsequently selected for analysis in terms of the Product and Organisational Architecture framework. While it was evident that the traditional models are followed in Africa, in some instances variations were apparent. Full-service network carriers and regional carriers were concluded as being the most prominent and stable in the African market. The applicability of the low-cost carrier model in Africa was also examined at length, with mixed results. The analysis also raised network density and connectivity as essential components of business models for delivering profits in an African context

The strategic evolution of Aer Lingus from a full-service airline to a low-cost carrier and finally positioning itself into a value hybrid airline

Aer Lingus has been an unique airline as it transitioned from a full-service airline to a low-cost carrier and is currently positioned as a value hybrid airline. It has coexisted with Ryanair for decades and it encountered three imminent periods where bankruptcy prevailed from 1993 to 2009. The research aims to uncover the various strategies that were applied to structurally re-engineer the carrier in order to adapt to its evolving competitive landscape. The key pillars underpinning Aer Lingus’ turnaround as a value hybrid were as follows: strict adherence to capacity discipline; relentless cost control and value-adding, consumer-driven product differentiation; innovative partnerships including contract flying to alleviate its problematic seasonality issues inherent in Aer Lingus markets; and by re-engineering its Dublin-based hub airport. A visionary master plan for the hub was fabricated to capitalize on Ireland’s geographical positioning which targeted the traffic flows between UK/European and North American destinations through its synchronized connection network at Dublin

Conflicts in Development: Tourism and the Cattle Industry in Brazil

This paper challenges the conventional view that where there is a political elite, economic development will proceed along lines that sacrifice future generations for the benefit of the current ruling class. We find that shortfalls in the balance of payments will cause those in authority to promote activities that encourage tourism as a solution to balance of payments deficit. The vehicle for generating tourism is the provision of public goods. More traditional paths toward development particularly cattle ranching are displaced by tourist attractions. While motivated by myopic self-interest, the pursuit of public goods reduces the amount of debt transferred to future generations and thereby serves to redistribute wealth inter-temporally. Brazil over the period 1965 until 1998 is used as a test case.tourism, cattle, ecotourism, public goods

POLICY options

End of project reportThe incomes of Irish cattle farmers benefited greatly from the reform of the CAP for beef and cereals in 1992 and more recently under Agenda 2000. In both of these reforms the institutional support prices were reduced and animal-based direct payments (DPs) were used to compensate farmers for the anticipated market price reductions

Development of a Strategic Approach for a Single EU Beef Market. Extensification. An Analysis of National and Competitive Issues

Working paperThe economic merits of the two Options for extensification under Agenda 2000 were evaluated in relation to their ability to generate revenue and their impact on the competitiveness of Irish cattle farming

The impact of feed resource costs on the relative competitiveness of beef with other meats

End of year reportThese reforms represented a major turning point in fundamental structure of EU agricultural policy. This, at the time of implementation, created much uncertainty at both institutional and farm level in relation to future feed resource costs, cattle and beef prices and related market outlooks. However, as this report shows, the reality for Irish cattle farmers was rather different. As a result much of the research effort during the lifespan of the project was diverted to explaining the causes of the unforeseen outcomes together with the implications of policy decisions and related market developments

An examination of ongoing trends in airline ancillary revenues

The airline industry seems permanently embedded in producing thin margins and continuously combatting downward pressure on yields. To perpetuate the problem, the industry remains eclipsed with high cost structures and low barriers to entry. However, a new sizzling concept continues to counterbalance these effects in the form of ancillary revenues. Globally, these revenues have increased by 121% from 2010 to 2014 – and the trend is set to continue as carriers are quickly implementing structural changes to accommodate these revenues streams. This paper examines the performance of the two core classifications of ancillary revenues, which are unbundled products and commission based income. It also investigates the willingness of passengers to pay for these services together with what type of ancillary items are acceptable at a particular price point. The study found that passengers value a narrow range of perceived ‘necessity’ products and services such as food and drink, checked baggage and seat assignment as opposed to perceived ‘optional’ unbundled or commission based products/services. It also found significant differences in WTP for specific ancillary services based on carrier type (FSC/LCC/Charter), length of flight (long and short haul) and journey purpose (business, leisure, VFR)

Liberalization of China-US air transport market: assessing the impacts of the 2004 and 2007 protocols

This paper examines China's considerations in reaching the 2004 and 2007 Air Service Agreement Protocols with the United States (US) and the impacts of such policy on the China–US market from the perspective of China. Analysis shows that the 2004 and 2007 protocols have profound impacts on the China–US market. The two protocols have been associated with phenomenal traffic growth and intensified competition. Passengers also benefit from much more choice in terms of both airlines and routing. Over time, Chinese carriers' operating performance and financial performance have gradually improved after the liberalization expressed in the protocols. However, the industry's hub-building initiatives are still seriously challenged by competing hubs in Seoul and Tokyo which have diverted substantial number of passengers moving between the China and US markets. Such issues have to be addressed in order to create a win–win outcome for both countries

An ecological approach to the management of gulls, in particular the lesser black-backed gull Larus Fuscus (L. 1758)

A study of gull management was made at a large colony of Lesser Black-backed Gulls Ljxrus fuscus on Tambrook Fell, Lancashire. Approximately 18,000 gulls presently breed at the site, and the area utilised by the gulls extends over 6 km2 on three private estates. The main studies were conducted on the Abbeystead Estate between 1992 and 1994. The reasons for increases in the numbers of several gull species in many parts of the world during the 20th century are presented, as well as the conflicts with humans caused by these increases. The practical and moral aspects of managing gulls are evaluated, as well as the conflicts likely to result from recent increases in the urbanisation of several Larid species. The need for management strategies to incorporate up-to-date knowledge of gull demography, density dependence, breeding biology and behaviour are discussed in the light of the limited success of past attempts at managing gulls. Experiments to entirely clear specific areas of the Tambrook Fell Gullery by disturbing breeding gulls are described. The aim was to ameliorate local problems by reducing the extent of the colony using non-lethal management techniques. Disturbance was carried out in a series of 2.25ha experimental plots. Audio, visual and physical disturbance methods, presented singly or in combination, were used to investigate their ability to exclude gulls and prevent breeding. The number of gulls using the plots and the number of nests built were compared with numbers on control plots. Gulls showed habituation to all disturbance methods, although the number of gulls using a plot was reduced during disturbance and a proportion of the original number of gulls were totally excluded. Only where two disturbance methods were utilised on the same plot was breeding completely prevented. It was demonstrated that disturbance was more effective when initiated prior to the start of nest building and when conducted at the edge of the colony, and that disturbance by human presence is an effective method of preventing breeding. In the year following disturbance, only a very few gulls attempted to utilise the disturbed areas, and the need to establish a 'sink' area for birds displaced by disturbance is discussed. In two seasons, a total of 75ha were cleared of breeding gulls. This was 23% of the Abbeystead Estate and 11 % of the total gullery area. This was the first time in over thirty years of management efforts at the colony, that the extent of the gullery was successfully reduced. Models are presented to show the effects of the 1978- 1988 culls on adult survivorship and recruitment into the breeding group at Tambrook Fell. The relative effects of management strategies aimed at survivorship and productivity are discussed. A study was made to quantify the percentage of nests built by gulls at the colony that are not subsequently laid in. Behavioural differences between pairs that failed to lay eggs and pairs that successfully bred are presented. In the past, calculations of the number of breeding gulls at the colony assumed that one nest represented one pair. This was shown not to be true and a correction factor (multiplier) of 0.61 was calculated to allow counts of nests at the colony to be converted to the number of breeding pairs