A Minimal Representation for Dead-Reckoning Navigation: Updating the Homing Vector

A number of organisms are capable of traveling directly back to the origin of locomotion after following a circuitous outbound path, using dead-reckoning navigation. We describe a minimal representation that could be used for such navigation. It involves keeping track of only the polar coordinates of the origin of locomotion with respect to the observer's current location. An exact solution is provided first, followed by a simplified solution, then a solution involving linearization of trigonometric functions. The paper also examines performance attainable with these solutions and briefly considers ways in which the model might be modified to account for human navigation without reference to landmarks.     

Recent Theoretical Paradigms in Urban Growth

The aim of this article is to present a critical view of the theoretical toolboxes developed in urban economics to explain urban city size. The article starts with the consideration that, during the 1960s and 1970s, the question of optimal city-size tended to be expressed in a misleading way. The real issue is not an “optimal city size” but an “efficient size”, which depends on the functional characteristics of the city and on the spatial organization within the urban system. Economies of scale exist up to a certain city size. However, urban development generates conditions leading to structural readjustments which lead to new economic advantages. These structural adjustments may be either sectoral transformations towards higher-order functions, or the emergence of external linkages with other cities. The article provides recent empirical evidence of the role played by urban functions and city networking in explaining urban equilibrium size. The empirical analyses reported here witness the importance of the structural adjustment of cities needed to achieve a higher equilibrium size.     

A Reappraisal of Dinas Powys: Local Exchange and Specialized Livestock Production in 5th- to 7th-century Wales

RESULTS OF THE analysis of a previously unstudied group of animal bone from Dinas Powys are tested against the original report and subsequent interpretations. Assumptions inherent in the initial sampling policy and analysis are discussed. The present interpretation explores the concept of social production in early medieval Wales.     

Competitiveness through integration in the European Union Strategy for the Alpine Region: a ‘balanced development’ approach

In the last 10 years, the European Union has devoted specific attention and resources to the establishment of macro-regional strategies, with the objective of joining together transnational areas to favour the effective and organized management of common challenges. In most macro-regions, however, the identification of strategies to increase competitiveness is a rather difficult task, given the extreme internal diversity in economic activities. Focusing on the youngest macro-regional strategy – EUSALP – this paper highlights the specific combinations of territorial growth assets that allow to overcome the inefficient use of local abundant strategic resources, in line with a ‘balanced development’ approach. The results, obtained on the basis of a database gathered at NUTS3 level, are useful to provide policy suggestions to support the competitiveness of EUSALP through synergies and complementarities, according to a cooperation networks perspective.     

Ethical consumption? There's an app for that. Digital technologies and everyday consumption practices

Ethical consumption mobile phone apps are increasingly popular. These apps allow consumers to scan the barcodes of products they are considering purchasing and determine whether or not they align with their ethics. App technologies are often applauded for their potential to provide consumers with targeted, crowd-sourced information about products while shopping and to foster more political, and less individualistic, consumption practices by connecting users to one another and to campaigns. There is a growing field of scholarship conceptually examining the role of information and digital technologies in ethical consumption. However, there is little empirical research on how consumers engage with ethical consumption apps in everyday ways. Drawing on an in-depth study with 21 participants, this paper explores how app use mediates people's experiences of ethical consumption. We contend that the app design structures and limits how individuals engage in ethically motivated consumption and influences their conceptualizations of ethical consumption as a political practice. We conclude by illustrating that critically examining what it means to be “ethical” in a digital world is a crucial area of research for geographers, particularly as these ethics play out through the everyday use of mobile technologies.     

Non-invasive characterization through X-ray fluorescence and neutron radiography of an ancient Japanese lacquer

Oriental lacquer artefacts represent very interesting objects of investigation, involving a huge variety of materials and manufacturing techniques. Lacquers are very attractive not only for their stylistic features but also for understanding the variety of production processes, time evolution, use and artistic applications involved in their manufacturing. Till recently, the research activity on these materials has been mainly based on standard, more or less invasive, analytical methods. With the aim to characterise a nineteenth century Japanese lacquer in a totally non-invasive and non-destructive way, in situ X-ray fluorescence (XRF) and neutron radiography (NR) have been employed. While XRF suggested an identification of the pigments embedded into superficial layers, NR allowed revealing, in a single measurement, the average bulk properties of the sample.