Search results for "Abstract"
showing 10 items of 1959 documents
A Hidden Markov Model for Automatic Generation of ER Diagrams from OWL Ontology
2014
Connecting ontological representations and data models is a crucial need in enterprise knowledge management, above all in the case of federated enterprises where corporate ontologies are used to share information coming from different databases. OWL to ERD transformations are a challenging research field in this scenario, due to the loss of expressiveness arising when OWL axioms have to be represented using ERD notation. In this paper we propose an innovative technique for estimating the most likely composition of ERD constructs that correspond to a given sequence of OWL axioms. We model such a process using a Hidden Markov Model (HMM) where the OWL inputs are the observable states, while E…
MetaEdit— A flexible graphical environment for methodology modelling
1991
Existing CASE tools are often rigid and do not support the users' native methodologies. To alleviate this, more flexible and customisable tools called CASE shells are emerging. However, the customisation of those tools is still cumbersome and error-prone, and demands several configuration files that follow a rigid syntax of some metamodelling language(s). In order to make the customisation easier, we propose a graphical metamodelling editor, MetaEdit, with which the conceptual structures of the user methodology can be modelled easily using an easy-to-grasp graphical notation. With MetaEdit, methodology models can be constructed with less effort and the configuration files for the CASE shell…
Graphical Template Language for Transformation Synthesis
2010
Higher-Order Transformations (HOT) have become an important support for the development of model transformations in various transformation languages. Most frequently HOTs are used to synthesize transformations from different kinds of models, for example, mapping models. This means that model driven development (MDD) is being successfully applied to transformations themselves too. The standard HOT solution is to create the transformation as a model using the abstract syntax. However, for graphical transformation languages a significantly more efficient solution would be to create the transformation using its graphical (concrete) syntax. An analogy could be the textual template languages such…
Formalized classification of ephemeral wetland vegetation (Isoëto-Nanojuncetea class) in Poland (Central Europe)
2021
Formalized classification of the class Isoëto-Nanojuncetea has not been performed in Poland. We used 69,562 relevés stored in Polish Vegetation Database. Based on the literature and expert knowledge we selected 63 diagnostic species for the Isoëto-Nanojuncetea class. Unequivocal classification was applied in this work according to Cocktail method. A set of formal definitions was established using a combination of logical operators of total cover of species in case of high-rank syntaxa while sociological species groups and cover of particular species were used for logical formulas describing class, alliances and associations. An Expert System was prepared and applied to classify the whole da…
What Is Synthetic Biology?
2014
Synthetic biology aims at the design and construction of biological devices and systems for useful purposes. From an ideal engineering perspective synthetic biology works from rational design made through a few conceptual pillars, namely abstraction, standardization and modularity. Nevertheless, the combination of our still fragmentary biological knowledge and the messy nature of biological devices are major challenges for engineering life in a predictive manner. It is urgent to build bridges between different disciplines, from biology to engineer and back, to pursue this extraordinary goal of making life.
Getting even with CLE
2018
In the landscape of approaches toward the simulation of Lattice Models with complex action the Complex Langevin (CL) appears as a straightforward method with a simple, well defined setup. Its applicability, however, is controlled by certain specific conditions which are not always satisfied. We here discuss the procedures to meet these conditions and the estimation of systematic errors and present some actual achievements.
Error Estimates of Theoretical Models: a Guide
2014
This guide offers suggestions/insights on uncertainty quantification of nuclear structure models. We discuss a simple approach to statistical error estimates, strategies to assess systematic errors, and show how to uncover inter-dependencies by correlation analysis. The basic concepts are illustrated through simple examples. By providing theoretical error bars on predicted quantities and using statistical methods to study correlations between observables, theory can significantly enhance the feedback between experiment and nuclear modeling.
A probabilistic condensed representation of data for stream mining
2014
Data mining and machine learning algorithms usually operate directly on the data. However, if the data is not available at once or consists of billions of instances, these algorithms easily become infeasible with respect to memory and run-time concerns. As a solution to this problem, we propose a framework, called MiDEO (Mining Density Estimates inferred Online), in which algorithms are designed to operate on a condensed representation of the data. In particular, we propose to use density estimates, which are able to represent billions of instances in a compact form and can be updated when new instances arrive. As an example for an algorithm that operates on density estimates, we consider t…
Tasks for enriching the understanding of the concept of linear span
2018
International audience; The concept of linear span is one of the first abstract notions that students encounter in a course on Linear Algebra. Using the theoretical construct of concept image and concept definition (Tall & Vinner, 1981) along with observations about teaching and learning Linear Algebra, we present two tasks designed to enrich students' concept image regarding linear span. These tasks could be included in a problem workshop of an introductory university course on Linear Algebra. Each task is carefully created and/or selected so as to foster the ground for potential conflict factors to arise and be confronted. A preliminary evaluation shows that the tasks are well received by…
On the power of inductive inference from good examples
1993
Abstract The usual information in inductive inference available for the purposes of identifying an unknown recursive function f is the set of all input/output examples (x,f(x)),n eN. In contrast to this approach we show that it is considerably more powerful to work with finite sets of “good” examples even when these good examples are required to be effectively computable. The influence of the underlying numberings, with respect to which the identification has to be realized, to the capabilities of inference from good examples is also investigated. It turns out that nonstandard numberings can be much more powerful than Godel numberings.