Von der Lust, vernetzt zu sein

'Die Teletechnologien ermöglichen eine erotische oder vielleicht auch irgendwann sexuelle Begegnung aus der Ferne. Kulturkritiker sehen in solchen über die Technologie vermittelten Beziehungen in aller Regel nur eine Entfremdung. In der Tat bilden sich in den Computernetzen neue Formen der erotischen Beziehungen heraus, die unter der Bedingung der Anonymität und der Möglichkeit stattfinden, sich eine andere Identität zuzulegen. Wie immer gehen neuen technologischen Möglichkeiten Wünsche und Praktiken vorher, die sie gewissermaßen vorbereiten. Erotik und sexuelles Begehren waren nie einzig an die körperliche Anwesenheit eines anderen Menschen gebunden. Doch der Cyberspace, der Telebeziehungen erlaubt, könnte die paradoxale Erfüllung einer Intimität unter der Bedingung äußerster Fremdheit ermöglichen, eine sexuelle Verschmelzung von einsamen Menschen, die buchstäblich ihren Abstand wahren und ihre individuellen Wünsche einlösen, ohne sich preisgeben zu müssen.' (Autorenreferat

Bayesian and frequentist analysis of an Austrian genome-wide association study of colorectal cancer and advanced adenomas

Most genome-wide association studies (GWAS) were analyzed using single marker tests in combination with stringent correction procedures for multiple testing. Thus, a substantial proportion of associated single nucleotide polymorphisms (SNPs) remained undetected and may account for missing heritability in complex traits. Model selection procedures present a powerful alternative to identify associated SNPs in high-dimensional settings. In this GWAS including 1060 colorectal cancer cases, 689 cases of advanced colorectal adenomas and 4367 controls we pursued a dual approach to investigate genome-wide associations with disease risk applying both, single marker analysis and model selection based on the modified Bayesian information criterion, mBIC2, implemented in the software package MOSGWA. For different case-control comparisons, we report models including between 1-14 candidate SNPs. A genome-wide significant association of rs17659990 (P=5.43x10(-9), DOCK3, chromosome 3p21.2) with colorectal cancer risk was observed. Furthermore, 56 SNPs known to influence susceptibility to colorectal cancer and advanced adenoma were tested in a hypothesis-driven approach and several of them were found to be relevant in our Austrian cohort. After correction for multiple testing (alpha=8.9x10(-4)), the most significant associations were observed for SNPs rs10505477 (P=6.08x10(-4)) and rs6983267 (P=7.35x10(-4)) of CASC8, rs3802842 (P=8.98x10(-5), COLCA1,2), and rs12953717 (P=4.64x10(-4), SMAD7). All previously unreported SNPs demand replication in additional samples. Reanalysis of existing GWAS datasets using model selection as tool to detect SNPs associated with a complex trait may present a promising resource to identify further genetic risk variants not only for colorectal cancer

Accuracy, realism and general applicability of European forest models

Forest models are instrumental for understanding and projecting the impact of climate change on forests. A considerable number of forest models have been developed in the last decades. However, few systematic and comprehensive model comparisons have been performed in Europe that combine an evaluation of modelled carbon and water fluxes and forest structure. We evaluate 13 widely used, state-of-the-art, stand-scale forest models against field measurements of forest structure and eddy-covariance data of carbon and water fluxes over multiple decades across an environmental gradient at nine typical European forest stands. We test the models\u27 performance in three dimensions: accuracy of local predictions (agreement of modelled and observed annual data), realism of environmental responses (agreement of modelled and observed responses of daily gross primary productivity to temperature, radiation and vapour pressure deficit) and general applicability (proportion of European tree species covered). We find that multiple models are available that excel according to our three dimensions of model performance. For the accuracy of local predictions, variables related to forest structure have lower random and systematic errors than annual carbon and water flux variables. Moreover, the multi-model ensemble mean provided overall more realistic daily productivity responses to environmental drivers across all sites than any single individual model. The general applicability of the models is high, as almost all models are currently able to cover Europe\u27s common tree species. We show that forest models complement each other in their response to environmental drivers and that there are several cases in which individual models outperform the model ensemble. Our framework provides a first step to capturing essential differences between forest models that go beyond the most commonly used accuracy of predictions. Overall, this study provides a point of reference for future model work aimed at predicting climate impacts and supporting climate mitigation and adaptation measures in forests

Accuracy, realism and general applicability of European forest models

Forest models are instrumental for understanding and projecting the impact of climate change on forests. A considerable number of forest models have been developed in the last decades. However, few systematic and comprehensive model comparisons have been performed in Europe that combine an evaluation of modelled carbon and water fluxes and forest structure. We evaluate 13 widely used, state-of-the-art, stand-scale forest models against field measurements of forest structure and eddy-covariance data of carbon and water fluxes over multiple decades across an environmental gradient at nine typical European forest stands. We test the models' performance in three dimensions: accuracy of local predictions (agreement of modelled and observed annual data), realism of environmental responses (agreement of modelled and observed responses of daily gross primary productivity to temperature, radiation and vapour pressure deficit) and general applicability (proportion of European tree species covered). We find that multiple models are available that excel according to our three dimensions of model performance. For the accuracy of local predictions, variables related to forest structure have lower random and systematic errors than annual carbon and water flux variables. Moreover, the multi-model ensemble mean provided overall more realistic daily productivity responses to environmental drivers across all sites than any single individual model. The general applicability of the models is high, as almost all models are currently able to cover Europe's common tree species. We show that forest models complement each other in their response to environmental drivers and that there are several cases in which individual models outperform the model ensemble. Our framework provides a first step to capturing essential differences between forest models that go beyond the most commonly used accuracy of predictions. Overall, this study provides a point of reference for future model work aimed at predicting climate impacts and supporting climate mitigation and adaptation measures in forests.Peer reviewe

<scp>ReSurveyEurope</scp>: A database of resurveyed vegetation plots in Europe

AbstractAimsWe introduce ReSurveyEurope — a new data source of resurveyed vegetation plots in Europe, compiled by a collaborative network of vegetation scientists. We describe the scope of this initiative, provide an overview of currently available data, governance, data contribution rules, and accessibility. In addition, we outline further steps, including potential research questions.ResultsReSurveyEurope includes resurveyed vegetation plots from all habitats. Version 1.0 of ReSurveyEurope contains 283,135 observations (i.e., individual surveys of each plot) from 79,190 plots sampled in 449 independent resurvey projects. Of these, 62,139 (78%) are permanent plots, that is, marked in situ, or located with GPS, which allow for high spatial accuracy in resurvey. The remaining 17,051 (22%) plots are from studies in which plots from the initial survey could not be exactly relocated. Four data sets, which together account for 28,470 (36%) plots, provide only presence/absence information on plant species, while the remaining 50,720 (64%) plots contain abundance information (e.g., percentage cover or cover–abundance classes such as variants of the Braun‐Blanquet scale). The oldest plots were sampled in 1911 in the Swiss Alps, while most plots were sampled between 1950 and 2020.ConclusionsReSurveyEurope is a new resource to address a wide range of research questions on fine‐scale changes in European vegetation. The initiative is devoted to an inclusive and transparent governance and data usage approach, based on slightly adapted rules of the well‐established European Vegetation Archive (EVA). ReSurveyEurope data are ready for use, and proposals for analyses of the data set can be submitted at any time to the coordinators. Still, further data contributions are highly welcome.</jats:sec

Modeling and control of reheating strategies for refractory metals

Bei der Produktion von Platten aus Refraktärmetallen werden mehrere Erwärmprozesse durchlaufen, welche einen entscheidenden Einfluss auf die Qualität des Endprodukts haben. Die vorliegende Arbeit befasst sich mit der Anwendung regelungstechnischer Methoden auf zwei Erwärmprozesse in einer Flachgüterproduktionslinie. Das Ziel ist in beiden Fällen die Reduktion von Zeit- und Energieverbrauch des jeweiligen Prozesses, wobei die Qualität des Produkts erhalten bleiben soll. Im ersten Teil der Arbeit werden die Kammeröfen einer Warmwalzanlage betrachtet. Durch Minimierung der Liegezeit der Produkte im Ofen wird Energie eingespart. Während des Erwärmens im Ofen kann die Produkttemperatur nicht gemessen werden. Deshalb wird ein detailliertes Prozessmodell eines Kammerofens erstellt und sukzessive auf ein nichtlineares Modell erster Ordnung reduziert, welches imstande ist, den zeitlichen Verlauf der Produktentnahmetemperatur hinreichend genau abzubilden. Das Modell erster Ordnung dient als Basis für eine Lernstrategie, die die Schätzung der minimalen Liegezeiten von Produkt zu Produkt verbessert. Darüber hinaus wird das Produktportfolio nach Materialeigenschaften und Oberflächenbeschaffenheit in Produktklassen eingeteilt, um die Genauigkeit der Schätzung weiter zu erhöhen. Die vorgeschlagene Lernstrategie mit mehreren Produktklassen wird anhand des validierten Prozessmodells in ausführlichen Simulationsstudien getestet. Für den Fall, dass die Produktparameter hinreichend genau bekannt sind, weisen die erzielten Ergebnisse eine sehr hohe Genauigkeit auf. Unsicherheiten in den Produktparametern zeigen einen mäßigen Einfluss auf das Schätzergebnis, welcher durch Einengung der Definitionen der Produktklassen weiter minimiert werden kann. Der entworfene Schätzer kann ohne großen Rechenaufwand implementiert werden und ist für eine Vielzahl von ähnlichen Öfen anwendbar. Der zweite Teil der Arbeit beschäftigt sich mit der induktiven Erwärmung in der Bandrollen-Produktionsanlage. Dünne Bleche werden entlang einer Schnittspur erwärmt, um die Qualität der Schnittkanten zu verbessern. Unebenheiten im Blech bewirken dabei Schwankungen des Luftspalts zwischen Induktor und Blech, welche wiederum starke Inhomogenitäten beim Erwärmen der Schnittspur nach sich ziehen. Das Ziel ist es nun, die Temperatur entlang jeder Schnittspur über einen vorgegebenen unteren Schwellwert zu bringen, ohne unnötig zu überheizen. Für das induktive Erwärmproblem wird zunächst ein detailliertes Prozessmodell erstellt und anschließend für den Reglerentwurf vereinfacht. Das resultierende Entwurfsmodell besteht dabei aus einer Transportgleichung für das thermische und einem Ersatzschaltbild für das elektromagnetische Teilsystem. Auf Basis des Entwurfsmodells wird dann ein kaskadierter Reglerentwurf durchgeführt. Der innere Kreis der Kaskade regelt die übertragene Heizleistung und über den äußeren Kreis wird die Temperatur entlang der Schnittspur über eine Zwei-Freiheitsgrad-Regelung, bestehend aus einem Vorsteuer- und einem Regleranteil, eingestellt und Schwankungen des Luftspaltmittelwerts ausgeglichen. Die Regelgüte des entworfenen Zwei-Freiheitsgrad-Reglers wird anschließend in Simulationsstudien am validierten Prozessmodell getestet. Die Ergebnisse zeigen, dass der Regler für einen hinreichend homogenen Luftspalt sehr gut arbeitet. Der Regler erlaubt verschiedene Erweiterungen, je nach Vorhandensein von Stellgrößen und Messinformationen.The production of plates from refractory metals involves several reheating processes that have a critical influence on the quality of the final product. This thesis deals with the application of control engineering methods to two reheating processes in a flat stock production line. The objective in both cases is to save time and energy in the reheating processes, while the quality of the products should not be compromised. In the first part of the thesis, batch-type chamber furnaces used in a hot rolling plant are considered. Energy saving is achieved by minimizing the residence times for each product that is charged into the furnace. When the product is in the furnace, its temperature cannot be measured. Therefore, a detailed process model of the chamber furnace is derived from first principles and subsequently reduced to a first-order nonlinear system, which is able to capture the time evolution of the discharge temperature of the product with sufficient accuracy. The first-order model is exploited in a learning strategy to improve the estimates of the minimum residence times from one product to the next. Additionally, the products of the plant are assigned to product classes according to their material and surface properties to further improve the estimation results. Simulation studies are performed with the validated detailed process model and the proposed learning strategy with different product classes. The results show a high accuracy if the product parameters are well known. Uncertainties in the product parameters have a moderate influence on the estimation results that can be mitigated by narrowing the definitions of the product classes. The designed estimator is computationally inexpensive and can be applied to a wide range of similar furnace systems. The second part of the thesis deals with an induction heating system used in the strip coil production. Thin sheets of refractory metals are reheated along a cutting line to improve the quality of the cutting edges. Flatness defects of the sheet cause fluctuations in the air gap between the inductor and the sheet, which entail strong temperature inhomogeneities. The goal is to bring the temperature along each cutting line above a minimum threshold without unnecessary overheating. The induction heating problem is formulated as a multiphysics process model, which is subsequently simplified for the controller design. The resulting control-oriented model consists of an advection equation and an equivalent circuit model. Based on the control-oriented model, a cascade controller for the transmitted heating power and a two-degrees-of-freedom temperature controller, comprising a feedforward and a feedback part, are designed to compensate for changes in the mean air gap. Based on the validated detailed process model, the performance of the designed temperature controller is tested in extensive simulation studies. The results show that the proposed controller performs well for sufficiently homogeneous air gap geometries. The concept allows for further improvements in several directions, depending on the available system inputs and outputs.12

There will be no Pluralism of Forms and Ways of Life without Universalism of Principles. Interview with Karl-Otto Apel

In an interview with Karl-Otto Apel, conducted and published by Florian Rötzer in 1987, a number of issues of Apel’s transcendental-pragmatic philosophy were discussed. The interview presents what was the subject of the main debates conducted at the time by this defender of reason and rationalist tradition in philosophy, who spoke out against all radical scepticism and was known above all as a philosopher defending the thesis of the need and the possibility of providing ultimate justification. Karl-Otto Apel explains how this thesis should be understood and what the transcendental-pragmatic ultimate justification consists of. The interview also expounds what is the argument of performative self-contradiction that is used in the final justification procedure. Apel refers to the critics directed at discourse ethics, its “formalism” of Kantian provenance (critics that accuse this current of ethics that it leads to the elimination of diversity and pluralism); his critical remarks are directed at the advocates of postmodernity and postmodernism. Karl-Otto Apel defends a universalistic model of ethics and a Kantian, purely formal image of man as an image which at the same time creates conditions for cultural pluralism and free articulation of dissent, as well as for the search for consensus.W wywiadzie z Karlem-Otto Aplem, jaki przeprowadził i w roku 1987 opublikował Florian Rötzer, omówionych zostało szereg wątków rozwijanej przez Apla filozofii transcendentalno-pragmatycznej. Wywiad ukazuje, co było przedmiotem głównych sporów i dyskusji prowadzonych w owym czasie przez tego obrońcę rozumu i racjonalistycznej tradycji w filozofii, który występował przeciwko wszelkiemu radykalnemu sceptycyzmowi i znany był przede wszystkim jako filozof broniący tezy o potrzebie i o możliwości dostarczenia uzasadnienia ostatecznego. Karl-Otto Apel wyjaśnia w tym wywiadzie, jak należy tę tezę rozumieć oraz na czym polega ostateczne uzasadnienie transcendentalno-pragmatyczne. W wywiadzie wyjaśnione też zostaje, czym jest argument z performatywnej samozaprzeczalności, który wykorzystywany jest w procedurze ostatecznego uzasadniania. W swych odpowiedziach Apel odnosi się do krytyk kierowanych pod adresem etyki dyskursowej, jej „formalizmu” o kantowskiej proweniencji (krytyk zarzucających temu nurtowi etyki, iż prowadzi do likwidacji różnorodności i pluralizmu); krytyczne uwagi kieruje pod adresem rzeczników postnowoczesności i postmodernizmu. W swych wywodach Apel broni uniwersalistycznej etyki oraz Kantowskiego, czysto formalnego obrazu człowieka jako obrazu, który zarazem stwarza warunki dla kulturowego pluralizmu oraz swobodnego artykułowania niezgody, a także dla poszukiwania konsensu