Exactly solvable variable parametric Burgers type models

Exactly solvable variable parametric Burgers type equations in one-dimension are introduced, and two different approaches for solving the corresponding initial value problems are given. The first one is using the relationship between the variable parametric models and their standard counterparts. The second approach is a direct linearization of the variable parametric Burgers model to a variable parametric parabolic model via a generalized Cole-Hopf transform. Eventually, the problem of finding analytic and exact solutions of the variable parametric models reduces to that of solving a corresponding second order linear ODE with time dependent coefficients. This makes our results applicable to a wide class of exactly solvable Burgers type equations related with the classical Sturm-Liouville problems for the orthogonal polynomials

Towards ecosystem-based restoration of peatland biodiversity

Natural peatlands support rich biological diversity at the genetic, species, ecosystem and landscape levels. However, because the character of this diversity differs from that of other ecosystem types, the value of peatlands for biodiversity has often been overlooked. Fundamentally, this arises because peatland ecosystems direct part of the energy captured by primary production into long-term storage within a peat layer, and thus establish a structural and functional basis for biodiversity maintenance that is not found elsewhere. This article examines the far-reaching implications for the assessment of peatland biodiversity as well as for the drivers, methods and targets of peatland conservation and restoration initiatives. It becomes clear that a robust framework for the management and restoration of peatland biodiversity must be founded in structural-functional ecosystem analysis, and such a framework is developed. The authors draw on a broad base of historical and contemporary literature and experience, including important Russian contributions that have previously had little international exposure

Two Phase Description Logic Reasoning for Efficient Information Retrieval

Description Logics are used more and more frequently for knowledge representation, creating an increasing demand for efficient automated DL reasoning. However, the existing implementations are inefficient in the presence of large amounts of data. This paper summarizes the results in transforming DL axioms to a set of function-free clauses of first-order logic which can be used for efficient, query oriented data reasoning. The described method has been implemented in a module of the DLog reasoner openly available on SourceForge to download

OWL-POLAR : semantic policies for agent reasoning

The original publication is available at www.springerlink.comPostprin

Get my pizza right: Repairing missing is-a relations in ALC ontologies (extended version)

With the increased use of ontologies in semantically-enabled applications, the issue of debugging defects in ontologies has become increasingly important. These defects can lead to wrong or incomplete results for the applications. Debugging consists of the phases of detection and repairing. In this paper we focus on the repairing phase of a particular kind of defects, i.e. the missing relations in the is-a hierarchy. Previous work has dealt with the case of taxonomies. In this work we extend the scope to deal with ALC ontologies that can be represented using acyclic terminologies. We present algorithms and discuss a system