5,355 research outputs found
Environmental accounting for ecosystem conservation: Linking societal and ecosystem metabolisms
This paper proposes an approach to environmental accounting useful for
studying the feasibility of socio-economic systems in relation to the external
constraints posed by ecological compatibility. The approach is based on a
multi-scale analysis of the metabolic pattern of ecosystems and societies and
it provides an integrated characterization of the resulting interaction. The
text starts with a theoretical part explaining (i) the implicit epistemological
revolution implied by the notion of ecosystem metabolism and the fund-flow
model developed by Georgescu-Roegen applied to environmental accounting, and
(ii) the potentials of this approach to create indicators to assess ecological
integrity and environmental impacts. This revolution also makes it possible to
carry out a multi-scale integrated assessment of ecosystem and societal
metabolisms at the territorial level. In the second part, two applications of
this approach using an indicator of the negentropic cost show the possibility
to characterize in quantitative and qualitative terms degrees of alteration
(crop cultivation, tree plantations)for different biomes (tropical and boreal
forests). Also, a case study for land use scenarios has been included. The
proposed approach represents an integrated multi-scale tool for the analysis of
nature conservation scenarios and strategies.Comment: 29 pages including 6 figure
Hermite-Birkhoff Interpolation on Arbitrarily Distributed Data on the Sphere and Other Manifolds
We consider the problem of interpolating a function given on scattered points
using Hermite-Birkhoff formulas on the sphere and other manifolds. We express
each proposed interpolant as a linear combination of basis functions, the
combination coefficients being incomplete Taylor expansions of the interpolated
function at the interpolation points. The basis functions have the following
features: (i) depend on the geodesic distance; (ii) are orthonormal with
respect to the point-evaluation functionals; and (iii) have all derivatives
equal zero up to a certain order at the interpolation points. Moreover, the
construction of such interpolants, which belong to the class of partition of
unity methods, takes advantage of not requiring any solution of linear systems
Local interpolation schemes for landmark-based image registration: a comparison
In this paper we focus, from a mathematical point of view, on properties and
performances of some local interpolation schemes for landmark-based image
registration. Precisely, we consider modified Shepard's interpolants,
Wendland's functions, and Lobachevsky splines. They are quite unlike each
other, but all of them are compactly supported and enjoy interesting
theoretical and computational properties. In particular, we point out some
unusual forms of the considered functions. Finally, detailed numerical
comparisons are given, considering also Gaussians and thin plate splines, which
are really globally supported but widely used in applications
An application of MSIASM to Chinese exosomatic energy metabolism
The methodology of Multi-Scale Integrated Analysis of Societal Metabolism (MSIASM) is applied to analyze the Chinese economy. This paper presents four tasks: (i) identifying a set of benchmarks that makes it possible to compare various characteristics of the Chinese economy with those of other country groups and the world (level) average; (ii) explaining the differences over the selected set of benchmarks, by looking at the characteristics of the various sub-sectors of the Chinese economy; (iii) understanding existing trends and future feasible future development paths for China by studying the existence of reciprocal constraints between the whole economy and its sub-sectors; andChina, Energy, Multi-Scale Integrated Analysis, Societal Metabolism,
Reconsideration of Dimensions and Curve Fitting Practice in Economics Elaborating on Georgescu-Roegen’s Economic Methodology
This paper is to examine the proper use of dimensions and curve fitting practices elaborating on Georgescu-Roegen’s economic methodology in relation to the three main concerns of his epistemological orientation. Section 2 introduces two critical issues in relation to dimensions and curve fitting practices in economics in view of Georgescu-Roegen’s economic methodology. Section 3 deals with the logarithmic function (ln z) and shows that z must be a dimensionless pure number, otherwise it is nonsensical. Several unfortunate examples of this analytical error are presented including macroeconomic data analysis conducted by a representative figure in this field. Section 4 deals with the standard Cobb-Douglas function. It is shown that the operational meaning cannot be obtained for capital or labor within the Cobb-Douglas function. Section 4 also deals with economists’ ?curve fitting fetishism?. Section 5 concludes this paper with several epistemological issues in relation to dimensions and curve fitting practices in economics.dimensions, logarithmic function, Nicholas Georgescu-Roegen, macroeconomics, Cobb-Douglas function, econometrics, curve fitting, transcendental production function
A Critical Analysis of Dimensions and Curve Fitting Practice in Economics
When dealing with sustainability we are concerned with the biophysical as well as the monetary aspects of economic and ecological interactions. This multidimensional approach requires that special attention is given to dimensional issues in relation to curve fitting practice in economics. Unfortunately, many empirical and theoretical studies in economics, as well as in ecological economics, apply dimensional numbers in exponential or logarithmic functions. We show that it is an analytical error to put a dimensional unit x into exponential functions ( a x ) and logarithmic functions ( x a log ). Secondly, we investigate the conditions of data sets under which a particular logarithmic specification is superior to the usual regression specification. This analysis shows that logarithmic specification superiority in terms of least square norm is heavily dependent on the available data set. The last section deals with economists’ “curve fitting fetishism”. We propose that a distinction be made between curve fitting over past observations and the development of a theoretical or empirical law capable of maintaining its fitting power for any future observations. Finally we conclude this paper with several epistemological issues in relation to dimensions and curve fitting practice in economics.dimensions, logarithmic function, curve fitting, logarithmic specification
Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MUSIASEM): An Outline of Rationale and Theory
This paper presents an outline of rationale and theory of the MuSIASEM scheme (Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism). First, three points of the rationale behind our MuSIASEM scheme are discussed: (i) endosomatic and exosomatic metabolism in relation to Georgescu-Roegen’s flow-fund scheme; (2) the bioeconomic analogy of hypercycle and dissipative parts in ecosystems; (3) the dramatic reallocation of human time and land use patterns in various sectors of modern economy. Next, a flow-fund representation of the MUSIASEM scheme on three levels (the whole national level, the paid work sectors level, and the agricultural sector level) is illustrated to look at the structure of the human economy in relation to two primary factors: (i) human time - a fund; and (ii) exosomatic energy - a flow. The three levels representation uses extensive and intensive variables simultaneously. Key conceptual tools of the MuSIASEM scheme - mosaic effects and impredicative loop analysis - are explained using the three level flow-fund representation. Finally, we claim that the MuSIASEM scheme can be seen as a multi-purpose grammar useful to deal with sustainability issues.Energy, Flow-Fund Model, Multi-Scale Integrated Analysis, Mosaic Effects, Impredicative Loop, Societal and Ecosystem Metabolism, Hierarchy, Multi-Purpose
Gli enzimi pancreatici in corso di terapia incretinica del diabete mellito tipo 2
La prevalenza del diabete mellito è in notevole aumento non solo nei paesi industrializzati, ma soprattutto nei paesi in via di sviluppo. I dati più recenti forniti dalla International Diabetes Federation (IDF) nel 2013 riportano l’esistenza di 382 milioni di pazienti diabetici in tutto il mondo, con la previsione di raggiungere i 592 milioni nel 2035. La prevalenza globale di diabete mellito stimata nel 2013 si assesta attorno all'8.3% nella popolazione fra i 20-79 anni d’età, raggiungendo una stima fra il 9-10% nei paesi più popolosi al mondo, come la Cina e l'India. Una prevalenza particolarmente elevata è stata osservata in Messico (12.6%) ed Egitto (16.8%), superiore a quella degli USA (9.2%) e della Germania (8.2%). Questi dati indicano che nel 2013, i 2/3 di tutti i diabetici riguardavano i paesi in via di sviluppo
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