Earthquake damage in underground roadways

Earthquake damage in underground roadways and mine workings is considered, with particular application to the mines operated by Solid Energy NZ Ltd., on the West Coast of New Zealand’s South Island. The scenario considered is the effect on the mine workings of an earthquake, of moment magnitude eight, being generated by a rupture of the Alpine fault. An empirical relation from the seismology literature is used to relate earthquake magnitude, distance from the epicentre and the peak ground acceleration resulting from the seismic waves. This relation is used to estimate the likely damage at the mine site. Also, the decay scale for Rayleigh (surface) waves is calculated and the implications for the mine workings considered. The two-dimensional scattering of shear (SH) seismic waves from the mine workings is considered. Analytical solutions relevant to various mine tunnel geometries are presented with the stress and displacement amplification, due to scattering from the mine workings, calculated and discussed

Impact of CO2 fertilization on maximum foliage cover across the globe's warm, arid environments

Satellite observations reveal a greening of the globe over recent decades. The role in this greening of the "CO2 fertilization" effect-the enhancement of photosynthesis due to rising CO2 levels-is yet to be established. The direct CO2 effect on vegetatio

New Divisions of Labour?: Comparative Thoughts on the Current Recession

This article argues that it is useful to compare the current recession with that which occurred three decades ago. Drawing on research undertaken at that time by Ray Pahl, it is suggested that four questions are once again revealing in the study of the current economic downturn: \'How have we come to be where we are currently?\', \'Who gets what?\', \'How do we know what we claim to know?\', and \'What sorts of lessons can be drawn to inform thinking about the future?\' The usefulness of asking these questions is discussed, even though the answers must await further research.Recession, Divisions of Labour, Community

Physical planning and community involvement: An experiment in the use of participation techniques in Mangaung, Bloemfontein

The purpose of city planning is to improve the quality of life of people. Planning therefore focuses on people and it is therefore logical that planning should be based normatively on the active participation of diverse groups in a society. The Urban Foundation, developers of a new extension of the black town of MANGAUNG in Bloemfontein, felt that the community of MANGAUNG should be consulted in the city planning process before planning the township. The National Institute for Personnel Research of the CSIR has been appointed to develop procedures to achieve this goal. Simulations and models were used to determine various planning alternatives. The models are exhibited at various places in MANGAUNG where residents usually contract. Respondents were asked to investigate the models and express their opinion on this. These opinions are based on a structured questionnaire. The results of the study can be summarized as follows: The study has shown that the communities can be successfully involved in the planning process if appropriate participation techniques are used. Various themes containing attitudes and preferences of respondents have emerged in this study. Most of these imply implications for the design and implementation of new layouts.This study should be seen in the context of MANGAUNG and does not normally apply to other communities

Interpreting Dark Matter Direct Detection Independently of the Local Velocity and Density Distribution

We demonstrate precisely what particle physics information can be extracted from a single direct detection observation of dark matter while making absolutely no assumptions about the local velocity distribution and local density of dark matter. Our central conclusions follow from a very simple observation: the velocity distribution of dark matter is positive definite, f(v) >= 0. We demonstrate the utility of this result in several ways. First, we show a falling deconvoluted recoil spectrum (deconvoluted of the nuclear form factor), such as from ordinary elastic scattering, can be "mocked up" by any mass of dark matter above a kinematic minimum. As an example, we show that dark matter much heavier than previously considered can explain the CoGeNT excess. Specifically, m_chi < m_Ge} can be in just as good agreement as light dark matter, while m_\chi > m_Ge depends on understanding the sensitivity of Xenon to dark matter at very low recoil energies, E_R ~ 6 keVnr. Second, we show that any rise in the deconvoluted recoil spectrum represents distinct particle physics information that cannot be faked by an arbitrary f(v). As examples of resulting non-trivial particle physics, we show that inelastic dark matter and dark matter with a form factor can both yield such a rise

Branched covers and matrix factorizations

Let $(S,\mathfrak n)$ be a regular local ring and $f$ a non-zero element of $\mathfrak n^2$. A theorem due to Kn\"orrer states that there are finitely many isomorphism classes of maximal Cohen-Macaulay $R=S/(f)$-modules if and only if the same is true for the double branched cover of $R$, that is, the hypersurface ring defined by $f+z^2$ in $S[[ z ]]$. We consider an analogue of this statement in the case of the hypersurface ring defined instead by $f+z^d$ for $d\ge 2$. In particular, we show that this hypersurface, which we refer to as the $d$-fold branched cover of $R$, has finite Cohen-Macaulay representation type if and only if, up to isomorphism, there are only finitely many indecomposable matrix factorizations of $f$ with $d$ factors. As a result, we give a complete list of polynomials $f$ with this property in characteristic zero. Furthermore, we show that reduced $d$-fold matrix factorizations of $f$ correspond to Ulrich modules over the $d$-fold branched cover of $R$.Comment: 17 pages, comments welcome. v2: correction to a mistake in Example 3.6 as well as other minor change

Social policy on the Web: the online institutional structure of social policy domains in the UK

Our traditional image of government is often of the Parliament or of bricks and mortar government service delivery offices, such as NHS hospitals or Benefits Agency sites. However, in an online world, government is increasingly seen and experienced through the internet. Moreover, in the online world, government websites can be readily connected into hyperlink networks. What do the online 'footprints' of social policy domains look like? And how do these online social policy networks relate to equivalent offline networks? This paper examines these questions in relation to three policy domains in the United Kingdom, namely: foreign affairs, health and education. It draws on large-scale web crawls and sophisticated web-metrics and Social Network Analysis techniques to map and compare the shapes of these different policy domains. It explores the shape, nature and make-up of these various online networks and the participants in them, including the relevant contribution of non-government and commercial websites. It considers whether or not online networks may reflect or contribute to social policy networks, or government ambitions of 'joined-up' service delivery, and whether jurisdictional boundaries are evident in the online world. In examining these topics, this paper seeks to provide an empirical and conceptual contribution to understanding 21 government and service delivery

Networks of communities and communities of networks in online government

Over the past decade the World Wide Web has become a core platform for the electronic operation of government. Yet the shape and nature of government presence on the Web and the online community in which it resides remains poorly understood and relatively under-theorised. This paper analyses large-scale web crawling data that map the hyperlink network structure between government websites and the broader Web ecology in the UK. In particular, it reports the ‘communities’ of websites within a hyperlink network of over 19,000 websites and over 135,000 hyperlinks derived from 75 key UK government seed sites at national, regional (i.e. Scotland and Wales) and local government levels. These website communities were derived by utilising Infomap, a state-of-the-art community detection algorithm that operate on the principle that flows of information in complex networks reveals community structure. Identifying and analysing online communities in which government websites reside provides insights in how hyperlink communities are arranged, that is, their emergent organizing principal and the importance of government in these online communities. It is hypothesized that online ‘communities’ can occur around different policy topics (such as health, education or policing), or along institutional or jurisdictional boundaries (such as England, Scotland and Wales). Using this novel approach this paper demonstrates that communities emerge on both axes, and that social media and government portals are some of the most significant communities based on information flows. This research provides foundational knowledge about the role of government websites in the World Wide Web, the emergent online associations, and the changing dynamic of state information in the twenty-first century. It points to strategies for developing government Web presence in networks that matter