461 research outputs found
Uncertainty assessment in 3-D geological models of increasing complexity
The quality of a 3-D geological model strongly depends on the type of integrated geological data, their interpretation and associated uncertainties. In order to improve an existing geological model and effectively plan further site investigation, it is of paramount importance to identify existing uncertainties within the model space. Information entropy, a voxel-based measure, provides a method for assessing structural uncertainties, comparing multiple model interpretations and tracking changes across consecutively built models. The aim of this study is to evaluate the effect of data integration (i.e., update of an existing model through successive addition of different types of geological data) on model uncertainty, model geometry and overall structural understanding. Several geological 3-D models of increasing complexity, incorporating different input data categories, were built for the study site Staufen (Germany). We applied the concept of information entropy in order to visualize and quantify changes in uncertainty between these models. Furthermore, we propose two measures, the Jaccard and the city-block distance, to directly compare dissimilarities between the models. The study shows that different types of geological data have disparate effects on model uncertainty and model geometry. The presented approach using both information entropy and distance measures can be a major help in the optimization of 3-D geological models
Techno-economic and environmental analysis of an Aquifer Thermal Energy Storage (ATES) in Germany
Abstract The objective of the present study is to analyse the economic and environmental performance of ATES for a new building complex of the municipal hospital in Karlsruhe, Germany. The studied ATES has a cooling capacity of 3.0 MW and a heating capacity of 1.8 MW. To meet the heating and cooling demand of the studied building, an overall pumping rate of 963 m3/h is required. A Monte Carlo Simulation provides a probability distribution of the capital costs of the ATES with a mean value of 1.3 ± (0.1) million €. The underground part of the ATES system requires about 60% of the capital costs and therefore forms the major cost factor. In addition, the ATES is compared with the presently installed supply technology of the hospital, which consists of compression chillers for cooling and district heating. Despite the 50% higher capital costs of the ATES system, an average payback time of about 3 years is achieved due to lower demand-related costs. The most efficient supply option is direct cooling by the ATES resulting in an electricity cost reduction of 80%. Compared to the reference system, the ATES achieves CO2 savings of about 600 tons per year, hence clearly demonstrating the potential economic and environmental benefits of ATES in Germany
Insights from an OTTR-centric Ontology Engineering Methodology
OTTR is a language for representing ontology modeling patterns, which enables
to build ontologies or knowledge bases by instantiating templates. Thereby,
particularities of the ontological representation language are hidden from the
domain experts, and it enables ontology engineers to, to some extent, separate
the processes of deciding about what information to model from deciding about
how to model the information, e.g., which design patterns to use. Certain
decisions can thus be postponed for the benefit of focusing on one of these
processes. To date, only few works on ontology engineering where ontology
templates are applied are described in the literature.
In this paper, we outline our methodology and report findings from our
ontology engineering activities in the domain of Material Science. In these
activities, OTTR templates play a key role. Our ontology engineering process is
bottom-up, as we begin modeling activities from existing data that is then, via
templates, fed into a knowledge graph, and it is top-down, as we first focus on
which data to model and postpone the decision of how to model the data.
We find, among other things, that OTTR templates are especially useful as a
means of communication with domain experts. Furthermore, we find that because
OTTR templates encapsulate modeling decisions, the engineering process becomes
flexible, meaning that design decisions can be changed at little cost.Comment: Paper accepted at the 14th Workshop on Ontology Design and Patterns
(WOP 2023
Bereichsrezension: Lars von Trier und seine Filme
Charles Martig: Kino der Irritationen. Lars von Triers theologische und ästhetische HerausforderungStefan Orth, Michael Staiger, Joachim Valentin (Hg.): Dogville Godville. Methodische Zugänge zu einem Film Lars von TriersMette Hjort (Ed.): On the five Obstructions<br /
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