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Auflistung nach Autor:in "Brüggemann, Rainer"

1 - 7 von 7
  • Konferenzbeitrag
    A Lattice-Theoretic Approach to Computing Averaged Ranks Illustrated on Pollution Data in Baden-Württemberg
    (Environmental Informatics and Systems Research, 2007) De Loof, Karel; De Baets, Bernard; De Meyer, Hans; Brüggemann, Rainer
    In the paper an algorithm for calculating the ranking distribution and the averaged ranking probability (averaged rank) of each element of a poset that avoids the enumeration of all linear extensions and relies on the lattice of ideals representation of the poset is presented.
  • Konferenzbeitrag
    A Software Platform Towards a Comparison of Cars - A Case Study for Handling Ratio-Based Decisions -
    (Innovations in Sharing Environmental Observations and Information, 2011) Wittmann, Jochen; Markert, Johann; Plura, Sebastian; Brüggemann, Rainer
    Environmental aspects often are in conflict with the criteria for a best/optimal behavior under technical aspects only. In these cases, common methods to compare alternatives and to come to a decision show methodological disadvantages. In this situation, this paper intends to demonstrate the situation firstly by giving a typical example, secondly to show, how a software platform might support the decision, thirdly, to provide different methods for comparison to demonstrate the effects of the method chosen and finally to sensitize the users for the interdependencies between the comparison method and the resulting ranking. The example will deal with the decision to find a new car according to individually scalable ratios. General data on different cars mainly are in conflict with the ratio of CO2-ratio expressing the environmental aspects of the cars to select. The paper proposes a software platform that allows dealing with these conflicting parameters by individually weighting and a flexible interface for comparison.
  • Konferenzbeitrag
    Data-Availability of Pharmaceuticals Detected in Water: An Evaluation Study by Order Theory (METEOR)
    (Environmental Informatics and Systems Research, 2007) Voigt, Kristina; Brüggemann, Rainer
    The topic of pharmaceuticals in the environment is of increasing interest both to the scientific community as well as to the public. Although extensive research is currently under way the availability of data on ecological parameters is largely missing. In our research approach we evaluate the data-availability of 16 widely spread pharmaceuticals in 17 publicly available Internet databases. We apply the order theoretical software METEOR which allows the participation of stakeholders in the evaluation process and the software provides the stepwise introduction of weight. We take a closer look at the chosen four point source pharmaceuticals, two cytostatic agents Cyclophoshamide (CYC), 5Fluorouracil (FLU) and two contrast media Diatrizoate (DIT), Iopromide (IOP). Even for these pharmaceuticals the data-situation is extremely bad. Only the large databases ChemExper Catalog of Chemical Suppliers, Physical Characteristics (CEX) and RXList The International Drug Index (RXL) comprise all of the chosen pharmaceuticals. It has to be mentioned however that neither of these databases contain data on ecotoxicity and/or degradation and accumulation.
  • Konferenzbeitrag
    Directional Adjustment of Average Rankings of Two Posets: an Application to Herb Layer and Moss Layer Pollution in Baden-Württemberg
    (Environmental Informatics and Systems Research, 2007) Rademaker, Michael; De Baets, Bernard; De Meyer, Hans; Brüggemann, Rainer
    In the paper two procedures for Directional adjustment of average rankings of two posets: an application to herb layer and moss layer pollution in Baden-Württemberg are disscussed.
  • Konferenzbeitrag
    Environmental Contamination with Endocrine Disruptors and Pharmaceuticals: An Environmetrical Evaluation Approach
    (Informatics for Environmental Protection - Networking Environmental Information, 2005) Voigt, Kristina; Brüggemann, Rainer; Pudenz, Stefan; Scherb, Hagen
    Achieving sustainable development in the environmental and health sector it is absolutely necessary to keep the ground- and consequently the drinking water free of contaminants. Unfortunately several chemicals are detected in environmental media. An intensive literature survey was performed for 7 environmental targets and the presence of 12 selected chemicals (pharmaceuticals and endocrine disruptors) therin. 75 articles recently published in international scientific journals performed the basis for the evaluation approach. The seven attributes to be looked upon the presence of at least one of the 12 drugs in those 7 environmental media. The consideration of the environmental media in any publication is coded by 0 (not available) or 1 (available). A 75 (objects) x 7 (attributes) data-matrix results. Several methods of mathematical and statistical background are applied. These are the Hasse Diagram Technique, a method derived from discrete mathematics, the POSAC (Partially Ordered Scalogram Analysis with Coordinates) method and the PCA (Principle Component Analysis), both multivariate statistical methods. Applying the Hasse Diagram Technique Method the most important publications are revealed as well as the least important ones. The PCA data-analysis method shows an exceptional position for the environmental media surface water and waste water.
  • Konferenzbeitrag
    Partial Order Concepts in Ranking Environmental Chemicals
    (Environmental Informatics and Systems Research, 2007) Brüggemann, Rainer; Voigt, Kristina; Sørensen, Peter B.; De Baets, Bernard
    With the discussion around REACH the interest in ranking of chemicals is increased. In this paper we take a statistical point of view in evaluation and ranking of chemicals. The data matrix with relevant properties of the chemicals plays the central role. Its evaluation is performed by simple concepts of partial order (Hasse diagram technique (HDT)). Several extensions are discussed: First the concept of METEOR (METhod of Evaluation by ORder Theory), then the approach by fuzzy concepts, combined with partial order, and finally the DLPO-concept (Double Layer Partial Orders). DLPO is a novel method where attributes are themselves combined by partial order. The main idea is to avoid the bias due to a functional combination of attributes (for example by weighted sums as in METEOR). Whereas HDT does not need any information beyond the data matrix, all other methods discussed so far, need additional knowledge.
  • Konferenzbeitrag
    Refrigerants ranked by Partial Order Theory
    (Environmental Informatics and Systems Research, 2007) Restrepo, Guillermo; Weckert, Monika; Brüggemann, Rainer; Gerstmann, Silke; Frank, Hartmut
    Forty refrigerants used in the past, used presently, and some proposed substitutes, were studied in respect to their ozone depletion potential, global warming potential, and atmospheric life times. They were ranked using the Hasse diagram technique, a mathematical method which permits to draw diagrams representing order relations among chemicals. The refrigerants were divided into 13 chemical classes (subsets) of which the most prominent ones are the chlorofluorocarbons (CFC), hydrofluorocarbons, hydrochlorofluorocarbons and hydrofluoroethers. Order relations among these subsets were calculated applying dominance and separability degrees. The dominance degree is a measure indicating the extent to which descriptors of members of one subset are higher than those of members of other subsets; the separability degree is a measure for the incomparability or lack of order relations between elements of two subsets. By application of these measures to the 13 chemical subsets it was found that more than half of the order relations among them are complete dominances; this means a high degree of comparability among subsets permitting to find the ones most problematic in environmental terms. This is the case for the CFC and for some of the hydrofluoroethers.