Towards a sustainable economy? Socio-technical transitions in the green building sector

Making the transition to a green economy is a major policy driver in the UK and other countries. Entrepreneurs are suggested as being at the forefront of this transition and as a driving force for sustainability. These “green entrepreneurs” may represent a new type of entrepreneurial behaviour combining economic, environmental and social aims. In this paper, we present empirical work conducted with green entrepreneurs in the UK green building sector. Buildings have significant impacts on the environment, both in terms of materials and post-construction energy demands. Drawing on sustainability transitions theory, we examine the role of green entrepreneurs in affecting change and suggest that green building niches are less consensual than previously theorised. In theorising green entrepreneurs, we also point to the need to consider them within wider networks of activity rather than as lone actors and the implications this has for policy

Comment on: Failure of the Work-Hamiltonian Connection for Free-Energy Calculations [Phys Rev Lett 100, 020601 (2008), arXiv:0704.0761]

We comment on a Letter by Vilar and Rubi [arXiv:0704.0761].Comment: one page, including one figure; to appear in Phys Rev Let

The Lebesgue Universal Covering Problem

In 1914 Lebesgue defined a "universal covering" to be a convex subset of the plane that contains an isometric copy of any subset of diameter 1. His challenge of finding a universal covering with the least possible area has been addressed by various mathematicians: Pal, Sprague and Hansen have each created a smaller universal covering by removing regions from those known before. However, Hansen's last reduction was microsopic: he claimed to remove an area of $6 \cdot 10^{-18}$, but we show that he actually removed an area of just $8 \cdot 10^{-21}$. In the following, with the help of Greg Egan, we find a new, smaller universal covering with area less than $0.8441153$. This reduces the area of the previous best universal covering by a whopping $2.2 \cdot 10^{-5}$.Comment: 11 pages, 5 jpeg figures, numerical errors correcte

AN ANALYSIS OF THE EFFECT OF PRICE ON RESIDENTIAL WATER DEMAND: METROPOLITAN MIAMI, FLORIDA

Resource /Energy Economics and Policy,

SOME ISSUES CONCERNING SPECIFICATION AND INTERPRETATION OF OUTDOOR RECREATION DEMAND MODELS

Resource /Energy Economics and Policy,

Institutionalizing alternative economic spaces? An interpretivist perspective on diverse economies

This article offers an approach that helps geographers and others to carefully and critically reexamine prospects for diverse economies. We propose an interpretative institutionalist perspective is useful for elucidating overlooked opportunities for creating alternative economic visions and practices by revealing the process of ‘meaning making’ undertaken by actors in the process of developing policy responses to various dilemmas. We explore this notion in the context of de-growth or post-growth. De-growth is a way of thinking about the economy in ways that are not growth oriented, or fixated on GDP, but on the redistribution of wealth and living within the Earth’s ecosystems

COMPONENTS OF OUTDOOR RECREATIONAL VALUES: KISSIMMEE RIVER BASIN, FLORIDA

Resource /Energy Economics and Policy,

Covariance analysis of the airborne laser ranging system

The requirements and limitations of employing an airborne laser ranging system for detecting crustal shifts of the Earth within centimeters over a region of approximately 200 by 400 km are presented. The system consists of an aircraft which flies over a grid of ground deployed retroreflectors, making six passes over the grid at two different altitudes. The retroreflector baseline errors are assumed to result from measurement noise, a priori errors on the aircraft and retroreflector positions, tropospheric refraction, and sensor biases

Estimation of Kalman filter model parameters from an ensemble of tests

A methodology for estimating initial mean and covariance parameters in a Kalman filter model from an ensemble of nonidentical tests is presented. In addition, the problem of estimating time constants and process noise levels is addressed. Practical problems such as developing and validating inertial instrument error models from laboratory test data or developing error models of individual phases of a test are generally considered

Convex Functions and Spacetime Geometry

Convexity and convex functions play an important role in theoretical physics. To initiate a study of the possible uses of convex functions in General Relativity, we discuss the consequences of a spacetime $(M,g_{\mu \nu})$ or an initial data set $(\Sigma, h_{ij}, K_{ij})$ admitting a suitably defined convex function. We show how the existence of a convex function on a spacetime places restrictions on the properties of the spacetime geometry.Comment: 26 pages, latex, 7 figures, improved version. some claims removed, references adde