1,782,036 research outputs found
Sustainable consumption: from escape strategies towards real alternatives
Better sustainability policy is supposed to lead to better sustainability performance. Nonetheless, recent research predicts further growth of the ecological footprint and stable ecological deficit in Europe and North America despite their impressive policy efforts (Lenzen et al. 2007) [1]. Similarly, individual strategies result in somewhat reduced load for committed consumers, but this reduction cannot offset the total impact of the socio-economic configuration: consumers in higher income countries tend to pollute more. Comitted consumers "offset" a part of their environmental load by carrying out green purchases. A radical change assumes a change in lifestyle (Shove, 2004) [2]. The conference paper is the first step of the study that aims at measuring the significance of attitude elements as compared to the significance of the socio-economic system on different elements of consumption and environmental aspects This paper focuses on measuring the ecological footprint impacts of consumption in different product groups as well as in different income groups of the society
Repetitive Delone Sets and Quasicrystals
This paper considers the problem of characterizing the simplest discrete
point sets that are aperiodic, using invariants based on topological dynamics.
A Delone set whose patch-counting function N(T), for radius T, is finite for
all T is called repetitive if there is a function M(T) such that every ball of
radius M(T)+T contains a copy of each kind of patch of radius T that occurs in
the set. This is equivalent to the minimality of an associated topological
dynamical system with R^n-action. There is a lower bound for M(T) in terms of
N(T), namely N(T) = O(M(T)^n), but no general upper bound.
The complexity of a repetitive Delone set can be measured by the growth rate
of its repetitivity function M(T). For example, M(T) is bounded if and only if
the set is a crystal. A set is called is linearly repetitive if M(T) = O(T) and
densely repetitive if M(T) = O(N(T))^{1/n}). We show that linearly repetitive
sets and densely repetitive sets have strict uniform patch frequencies, i.e.
the associated topological dynamical system is strictly ergodic. It follows
that such sets are diffractive. In the reverse direction, we construct a
repetitive Delone set in R^n which has
M(T) = O(T(log T)^{2/n}(log log log T)^{4/n}), but does not have uniform
patch frequencies. Aperiodic linearly repetitive sets have many claims to be
the simplest class of aperiodic sets, and we propose considering them as a
notion of "perfectly ordered quasicrystal".Comment: To appear in "Ergodic Theory and Dynamical Systems" vol.23 (2003). 37
pages. Uses packages latexsym, ifthen, cite and files amssym.def, amssym.te
First hitting time and place, monopoles and multipoles for pseudo-processes driven by the equation
Consider the high-order heat-type equation for an integer and introduce the related
Markov pseudo-process . In this paper, we study several
functionals related to : the maximum and minimum
up to time ; the hitting times and of the half lines
and respectively. We provide explicit expressions
for the distributions of the vectors and , as well
as those of the vectors and .Comment: 51 page
Mass Expansions of Screened Perturbation Theory
The thermodynamics of massless phi^4-theory is studied within screened
perturbation theory (SPT). In this method the perturbative expansion is
reorganized by adding and subtracting a mass term in the Lagrangian. We
analytically calculate the pressure and entropy to three-loop order and the
screening mass to two-loop order, expanding in powers of m/T. The truncated
m/T-expansion results are compared with numerical SPT results for the pressure,
entropy and screening mass which are accurate to all orders in m/T. It is shown
that the m/T-expansion converges quickly and provides an accurate description
of the thermodynamic functions for large values of the coupling constant.Comment: 22 pages, 10 figure
Exact solution of the one-dimensional ballistic aggregation
An exact expression for the mass distribution of the ballistic
aggregation model in one dimension is derived in the long time regime. It is
shown that it obeys scaling with a scaling
function for and for
. Relevance of these results to Burgers turbulence is discussed.Comment: 11 pages, 2 Postscript figure
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