EVALUATING ENVIRONMENTAL IMPACTS OF RURAL DEVELOPMENT PROJECTS

Discussions of "sustainable development" call attention to various dimensions of human well-being to be considered concomitantly with traditional financial and economic measures. The challenge of environmental impact analysis (EIA) is to encourage re-design of projects so that net benefits are maximized over some weighting of economic, environmental, and other criteria. To date, development organizations have been under attack by environmentalists for ignoring or conveniently overlooking environmental damages of development projects. Explanations for this include inadequate institutional commitment to link resource conservation with economic development, short time horizons, narrow evaluation criteria, problems of monetary valuation, and problems with implementation of EIAs. The future of EIAs will see a number of changes to correct for these deficiencies. Evaluation of project impacts in isolation may yield to a more comprehensive environmental assessment for entire regions. Projects will not be funded without the assurance of specific policy conditions for environmental management. The technology of EIA will advance with the assistance of geographic information systems and related tools for data management. Cost-benefit analysis of development projects will continue to integrate the work of project economists with engineers, agronomists, and other specialists with knowledge of environmental issues. Methods of multiple criteria evaluation represent an advance over the partial approaches of EIA and cost-benefit analysis. There is considerable support for moving towards longer project cycles and extended planning periods within the total cycle, meaning that EIA can be more extensive and continuous than in the past. Within the development organizations, reconsideration of personnel accountability and reward systems is one of the strategies to raise the prominence of environmental issues. Each year presents more case studies, videos, and other didactic materials for training in EIA. Finally, the question of improving EIA is a matter of demanding stronger institutions for proactive planning, technical analysis, and policy reforms favorable to environmental protection.Environmental Economics and Policy,

The Weyl-Heisenberg Group on the Noncommutative Two-Torus: A Zoo of Representations

In order to assess possible observable effects of noncommutativity in deformations of quantum mechanics, all irreducible representations of the noncommutative Heisenberg algebra and Weyl-Heisenberg group on the two-torus are constructed. This analysis extends the well known situation for the noncommutative torus based on the algebra of the noncommuting position operators only. When considering the dynamics of a free particle for any of the identified representations, no observable effect of noncommutativity is implied.Comment: 24 pages, no figure

Model of the early development of thalamo-cortical connections and area patterning via signaling molecules

The mammalian cortex is divided into architectonic and functionally distinct areas. There is growing experimental evidence that their emergence and development is controlled by both epigenetic and genetic factors. The latter were recently implicated as dominating the early cortical area specification. In this paper, we present a theoretical model that explicitly considers the genetic factors and that is able to explain several sets of experiments on cortical area regulation involving transcription factors Emx2 and Pax6, and fibroblast growth factor FGF8. The model consists of the dynamics of thalamo- cortical connections modulated by signaling molecules that are regulated genetically, and by axonal competition for neocortical space. The model can make predictions and provides a basic mathematical framework for the early development of the thalamo-cortical connections and area patterning that can be further refined as more experimental facts become known.Comment: brain, model, neural development, cortical area patterning, signaling molecule

Formulation and convergence of the finite volume method for conservation laws on spacetimes with boundary

We study nonlinear hyperbolic conservation laws posed on a differential (n+1)-manifold with boundary referred to as a spacetime, and defined from a prescribed flux field of n-forms depending on a parameter (the unknown variable), a class of equations proposed by LeFloch and Okutmustur in 2008. Our main result is a proof of the convergence of the finite volume method for weak solutions satisfying suitable entropy inequalities. A main difference with previous work is that we allow for slices with a boundary and, in addition, introduce a new formulation of the finite volume method involving the notion of total flux functions. Under a natural global hyperbolicity condition on the flux field and the spacetime and by assuming that the spacetime admits a foliation by compact slices with boundary, we establish an existence and uniqueness theory for the initial and boundary value problem, and we prove a contraction property in a geometrically natural L1-type distance.Comment: 32 page

Semi-classical Dynamical Triangulations

For non-critical string theory the partition function reduces to an integral over moduli space after integrating over matter fields. The moduli integrand is known analytically for genus one surfaces. The formalism of dynamical triangulations provides us with a regularization of non-critical string theory and we show that even for very small triangulations it reproduces very well the continuum integrand when the central charge $c$ of the matter fields is large negative, thus providing a striking example of how the quantum fluctuations of geometry disappear when $c \to -\infty$.Comment: 11 pages, 5 figure

A generalization of the Subspace Theorem with polynomials of higher degree

Recently, Corvaja and Zannier obtained an extension of the Subspace Theorem with arbitrary homogeneous polynomials of arbitrary degreee instead of linear forms. Their result states that the set of solutions in P^n(K) (K number field) of the inequality being considered is not Zariski dense. In our paper we prove by a different method a generalization of their result, in which the solutions are taken from an arbitrary projective variety X instead of P^n. Further, we give a quantitative version which states in a precise form that the solutions with large height lie ina finite number of proper subvarieties of X, with explicit upper bounds for the number and for the degrees of these subvarieties.Comment: 31 page

Operator product expansion and analyticity

We discuss the current use of the operator product expansion in QCD calculations. Treating the OPE as an expansion in inverse powers of an energy-squared variable (with possible exponential terms added), approximating the vacuum expectation value of the operator product by several terms and assuming a bound on the remainder along the euclidean region, we observe how the bound varies with increasing deflection from the euclidean ray down to the cut (Minkowski region). We argue that the assumption that the remainder is constant for all angles in the cut complex plane is not justified. Making specific assumptions on the properties of the expanded function, we obtain bounds on the remainder in explicit form and show that they are very sensitive both to the deflection angle and to the class of functions chosen. The results obtained are discussed in connetcion with calculations of the coupling constant \alpha_{s} from the \tau decay.Comment: Preprint PRA-HEP 99/04, 20 page

On joint distributions of the maximum, minimum and terminal value of a continuous uniformly integrable martingale

We study the joint laws of a continuous, uniformly integrable martingale, its maximum, and its minimum. In particular, we give explicit martingale inequalities which provide upper and lower bounds on the joint exit probabilities of a martingale, given its terminal law. Moreover, by constructing explicit and novel solutions to the Skorokhod embedding problem, we show that these bounds are tight. Together with previous results of Az\'ema & Yor, Perkins, Jacka and Cox & Ob{\l}\'oj, this allows us to completely characterise the upper and lower bounds on all possible exit/no-exit probabilities, subject to a given terminal law of the martingale. In addition, we determine some further properties of these bounds, considered as functions of the maximum and minimum.Comment: 19 pages, 4 figures. This is the authors' accepted version of the paper which will appear in Stochastic Processes and their Application

Representing fuzzy decision tables in a fuzzy relational database environment.

In this paper the representation of decision tables in a relational database environment is discussed. First, crisp decision tables are defined. Afterwards a technique to represent decision tables in a relational system is presented. Next, fuzzy extensions are made to crisp decision tables in order to deal with imprecision and uncertainty. As a result, with crisp decision tables as special cases fuzzy decision tables are defined which include fuzziness in the conditions as well as in the actions. Analogous to the crisp case, it is demonstrated how fuzzy decision tables can be stored in a fuzzy relational database environment. Furthermore, consultation of these tables is discussed using fuzzy queries.Decision making;