Optimal Scheduling of Trains on a Single Line Track

This paper describes the development and use of a model designed to optimise train schedules on single line rail corridors. The model has been developed with two major applications in mind, namely: as a decision support tool for train dispatchers to schedule trains in real time in an optimal way; and as a planning tool to evaluate the impact of timetable changes, as well as railroad infrastructure changes. The mathematical programming model described here schedules trains over a single line track. The priority of each train in a conflict depends on an estimate of the remaining crossing and overtaking delay, as well as the current delay. This priority is used in a branch and bound procedure to allow and optimal solution to reasonable size train scheduling problems to be determined efficiently. The use of the model in an application to a 'real life' problem is discussed. The impacts of changing demand by increasing the number of trains, and reducing the number of sidings for a 150 kilometre section of single line track are discussed. It is concluded that the model is able to produce useful results in terms of optimal schedules in a reasonable time for the test applications shown here

Tolkien’s Poetry (2013), edited by Julian Eilmann and Allan Turner

Tolkien’s Poetry (2013), edited by Julian Eilmann and Allan Turner. Book review by Andrew Higgins

Circular, No. 4

Many requests for information regarding the best varieties of field crops for interior Alaska have been received by the Alaska Agricultural Experiment Stations. Field crops have- been tested by the stations in the interior for a number of years. The purpose of this circular is to discuss briefly the history, characteristics, and field performance of varieties of grain, legumes, grasses, root crops, and potatoes that have been found to be best adapted to local conditions.Introduction -- Grain crops -- Legumes -- Grasses -- Root crops -- Potatoe

Building Imaginary Worlds (2012) by Mark J.P. Wolf and Revisiting Imaginary World (2016) edited by Mark J.P. Wolf

Book review of Building Imaginary Worlds (2012) by Mark J.P. Wolf and Revisiting Imaginary Worlds (2016), edited by Mark J.P. Wolf, reviewed by Andrew Higgin

The 'public inquisitor' as media celebrity

This article looks at the development and utility of celebrity among high-profile political interviewers. Offering the revised description 'public inquisitor', the article presents an overview of the rise of the political interviewer as a celebrity form of the 'tribune of the people' (Clayman 2002). It focuses on the UK-based journalists and broadcasters Jeremy Paxman and John Humphrys, and looks at the expansion of their professional activities and their attendant construction as media personalities. It argues that the forms of celebrity presented by Paxman and Humphrys draw upon discourses of integrity and authenticity associated with practices of advocacy, and suggests that their extension beyond the formal political realm into media genres traditionally excluded from the established political domain might work to consolidate the public inquisitor as a discursive figure. Therefore, while acknowledging that this depends on the effective management of individual media profiles, the article proposes a critical reappraisal of the place of the celebrity personae in political communication in order to account for the possibility of constructive modes of media performance

Stochastic Spot/Volatility Correlation in Stochastic Volatility Models and Barrier Option Pricing

Most models for barrier pricing are designed to let a market maker tune the model-implied covariance between moves in the asset spot price and moves in the implied volatility skew. This is often implemented with a local volatility/stochastic volatility mixture model, where the mixture parameter tunes that covariance. This paper defines an alternate model where the spot/volatility correlation is a separate mean-reverting stochastic variable which is itself correlated with spot. We also develop an efficient approximation for barrier option and one touch pricing in the model based on semi-static vega replication and compare it with Monte Carlo pricing. The approximation works well in markets where the risk neutral drift is modest.Comment: 23 pages, 11 figure

Populism and security in political speechmaking : the 2008 US Presidential Campaign

The issue of security has been a prominent feature of the US political landscape since the attacks of 9/11. Not surprisingly, then, issues of security, trust and credibility were raised throughout the 2008 US election presidential campaign. In the latter stages of his presidency, George W. Bush had been engaged in portraying his two terms as a successful period as national protector, keeping the US safe from further terrorist attack.Both the policy and the rhetorical strategies of the Bush administration coalesced around an emphasis on 'homeland security'. As well as producing a dominant way of asserting political legitimacy, this put in place an administrative framework within which elected legislators had to situate themselves, including the candidates for the 2008 presidential election