Johannes Wiedemann – författare

This open access dissertation explores how manufacturing-induced residual stress states in fiber metal laminates (FMLs) affect a structural health monitoring (SHM) system. SHM is a promising technology for monitoring the structural integrity during operation. SHM systems using guided ultrasonic waves (GUWs) enable the detection of damage located inside a laminate and are, therefore, particularly suitable for FMLs due to their complex damage characteristics. Experimental methods for quantifying residual stresses in FMLs are developed and evaluated. This work shows that process strains can be measured throughout manufacturing with sensors integrated into the laminate. The strain measurements verify different modified cure cycles to change residual stress states in FMLs consisting of carbon-fiber-reinforced polymer (CFRP) and steel. To avoid complex sensor technology in industrial manufacturing processes, a robust method is additionally presented that derives a process-specific parameter, the stress-free temperature, from asymmetrical reference laminates. The quantified residual stress states in various CFRP-steel laminates allow the experimental investigation of the influence of stress on the propagation velocity of fundamental GUWs. With laser-scanning-vibrometry, dispersion diagrams for various FMLs over a wide frequency range are experimentally determined. The results show no significant influence of the residual stress states on the phase velocity of the fundamental symmetric and asymmetric GUW modes for the investigated FMLs. In contrast, comparative measurements under external tensile prestress show a considerable increase in phase velocity with increasing prestress for both fundamental GUW. Finally, fatigue tests are performed on CFRP-steel laminates to investigate the influence of different residual stress states on the residual life prediction capabilities of an SHM system. The results show that reducing residual stresses through modified cure cycles delays crack initiation, reduces crack propagation velocity, and, consequently, extends the fatigue life of the investigated FMLs.

Leichtbau ist das Standardwerk dieses Arbeitsgebietes für Luft- und Raumfahrttechnik, Fahrzeugbau, Schiffs- und Meerestechnik, Maschinenbau, Fördertechnik, Stahlbau und Fertigungstechnik.Dieses eingeführte Werk behandelt eines der bedeutendsten Themen der Konstruktionstechnik. Leichtbau ist in allen Anwendungsgebieten wichtig geworden. Jeder Konstrukteur benötigt diesen Erfahrungsschatz.Dieser Reprint der zweiten Auflage ist in den dargestellten grundsätzlichen Methoden weiter auf aktuellem Stand, auch wenn in der Anwendung Fortschritte verzeichnet wurden. Der Reprint umfasst die beiden Einzelbände.Teil 1 beinhandelt Prinzipien und Strukturen des Leichtsbaus, dünnwandige isotrope Flächen und Hautfelder, dünnwandige Profilstäbe, anisotrope Flächen, Sandwichflächen, Flächen mit Einzelsteifen und Kastenträger für Biegung und Torsion. Im Teil 2 werden Kriterien und Verfahren des Entwerfens und Optimierens, der Auswahl und der beanspruchungsgerechten Gestaltung von Bauteilen und Strukturen auf der technologischen Basis aktueller Bauweisen und Werkstoffe, unter Gesichtspunkten der Zuverlässigkeit und der Schadenstoleranz behandelt.

Literature Review from the year 2010 in the subject Politics - Region: Western Europe, grade: 1,3, University of Southern Denmark (Department of Border Region Studies), course: European Contemporary History, language: English, abstract: Analysts of the question whether the European Union has characteristics of an empire like the German political scientist Herfried Munkler declare that the end of the Cold War and the resulting collapse of the Soviet Union led to a power vacuum in east-central Europe, a post-imperial space with a critical potential for instability. Therefore the European Union had to adapt to the new strategical situation by application of elements which are part of the traditional imperial order, like semi-permeable border regions, commonly accepted currency and lines of communication and a graduation from a center of power to client- and satellite-states. By chance, this was just the area in which the recent rounds of EU enlargement gathered new member states. On that score Jan Zielonka's book Europe as Empire can be seen as a contribution to a debate whether the process or current status of the European integration and enlargement has elements of imperical order or should have them. Zielonka, Professor of European Politics and Ralf Dahrendorf Fellow of the St Antony's College at Oxford University since 2004, promotes the hypothesis of Europe being an empire of a, as he calls it, neo-medieval paradigm exactly because of the characteristics of the admission of the post-socialist states to the European Union which is now an entity of twenty-seven nations of very different levels of political and economic significance. This, so the Zielonkas s argument goes, enlarged Union is more diversified and therefore will likely become a sphere of a blurred European identity and multilevel and multicentred governance without a centre of power or institutionalized hierarchy, something which Zielonka sees as remote resemblance of a medieval empire like the Holy Roman Empire of the German Nation which in fact was neither holy, nor roman or empire, but at least overarched the medieval German rag rug of duchies, electorates and kingdoms.

Essay from the year 2010 in the subject Politics - History of Political Systems, grade: 1,3, University of Flensburg (Internationales Institut fur Management), course: European Ideas - Populism"e;, language: English, abstract: Among scholars of political science it is deemed not worth asking whether a political movement in democracy is populist or not, it is only a question to what extent. Consensus has been established also on populism being understood as a pseudo- and post-democratic pathology of politics in western democracies produced by the public perception that democratic ideals are corrupted. So it seems worth discussing what extent of populism in the democratic discourse is a danger to democracy itself. As Francisco Panizza declared: "e;Taken to the extreme populism descends into totalitarianism"e;. What is an extreme of populism? And when does it start to be effective in the sense that it threatens a democratic system? The most prominent failure of democratic systems in modern history are the cases of the Weimar republic being taken over by the national socialists and the rise of fascism in the Italian republic after World War I, both examples of societies being in the transition phase from an authoritarian to a parliamentarian political system. For reasons of preserving clarity of argument, the latter example, Italian fascism and its leader, Benito Mussolini, shall serve as a reference point in order to point out what ideological ingredients and methods of communication of a totalitarian political movement are per definition "e;populist"e; and are able to gain popular support under specific political and historical conditions.

Seminar paper from the year 2010 in the subject Politics - Topic: European Union, grade: 1,7, University of Southern Denmark (Department of Border Region Studies), course: European Regional Innovation Policy, language: English, abstract: This paper is designed to examine the Regional Innovation Policy , consisting of existing schemes of systematic exploitation of innovation, so-called Regional Innovation Systems, and entailing public procurement for innovation and cluster-policies in combination with a mapping of the actors in the Regional Innovation System in the Baltic Sea Region, all in regard to Small Medium Enterprises due its pre-dominance in the fields of research and practical implementation of economic innovation. While the scope of this paper includes the effectiveness and efficiency of the "e;European Union Baltic Sea Region Programme"e; (EU BSRP) in reference to one of its priorities, "e;fostering innovation"e; for economical growth in the Baltic Sea Region, the programme's relative novelty in design and strategic relevance, given by the fact of promulgation of a "e;European Union Strategy for the Baltic Sea Region"e; (EU STRAT BSR) parallel to implementation of EU BSRP, point out to a demand for further investigation on the fact that the EU BSRP is an innovation by itself concerning regional policy as "e;macro-regional cooperation"e; within the framework of the EU. This paper will address firstly the EU STRAT BSR and its potential effects on the strategic environment in the Baltic Sea Region in particular and on European level in general by scrutinizing the second programmatic "e;pillar"e;, making "e;[...] [t]he Baltic Sea A Prosperous Place"e;, due to its reference character for the economic yield of the strategy. This short description and analysis of EU STRAT BSR is followed by an outline of the EU BSRP by providing an account of innovation policies in the Baltic Sea Region.Two research questions will serve as a guideline along the descriptive part and as reference to the analysis: Is political innovation in terms of transnational macro-regional cooperation also innovative and rewarding from the perspective of current economic research on innovation and according policies, meaning: Does it foster growth? And secondly, for the sake of the scope of European Studies, are EU STRAT BSR and EU BSRP able to perform even up to their political Level of Ambition?

Seminar paper from the year 2010 in the subject Politics - Topic: European Union, University of Flensburg, course: Course European Governance"e;, language: English, abstract: The concepts of governance have the advantage of including the informal aspect of decision-making into their scope of analysis. The intention of this paper is the application of a fitting conceptual derivative of governance on the decision making process inside the institutional framework of the Commission of the European Union. The notion to be tested is the one of the Commission being by its institutional heritage inclined to promulgation of consensus among its principal actors, the members of the college of Commissioners. So what kind of governance might be characteristic for the Commission?The political setting is that of the European Union, which is on the one hand an intergovernmental organization of member states on equal terms, but on the other hand a political institution. Apart from partly being established on a supra-national echelon, which is rationally designed and controlled for the purpose action and intervention to foster economic prosperity and integration in accordance with the concepts of functional and rational-choice institutionalism characteristic for social and political institutions of modernity. As the EU is itself an extension of the mostly politically pluralistic and socially fragmented Member States (MS), certain elements and processes influencing the promulgation of the political will on all legislative governmental echelons are present in the context of governance in the European Union as well. The hypothesis of this paper consists of the following notions:Due to the sui generis -character the EU,1 employing decisions by consensus even on intergovernmental as well as on supranational level is most effective politics possible. Applying concepts of governance to the Commission"e;s competences, institutional framework and formal as well as , if perceptible, informal decision-making procedures and customs, will show that although the Commission matches no distinct concept currently present in academia, it very well fulfils basic requirements of good"e; governance. Even as the supra-national institution per se, the Commission acts according to these notions.

Seminar paper from the year 2010 in the subject Politics - Political Theory and the History of Ideas Journal, grade: 2,0, University of Flensburg (International Institute for Management), course: European Ideas, language: English, abstract: If one explores the concept of scientific rationality as it was developed from Aristotle on over Thomas Aquinas to Ludwig Wittgenstein and beyond, one is surprised by the discovery that as all schools or approaches reflecting on knowledge, also the concept of scientific rationality is less a solid set of rules, but more a contested battleground of ideas. What are the conditions of scientific rationality? Is there scientific truth or certainty? Is there something or somebody beyond the boundaries of knowledge? What has Immanuel Kant in stock to contribute to answering these questions? That is the topic addressed in this paper: An outline of Kant"e;s concept of knowledge and a deriving theory of science with a backcloth of recent contributions of contemporary scientists, representing the current situation in this discussion. Kant and his thoughts on that matter are not the least suitable for depiction by the fact that his work undertook the mission to sooth the antagonismof rationalism and empiricism in his time which led not only to a synthesis, but to a re-assessment or even transformation of the respective theory as such.

Seminar paper from the year 2011 in the subject Politics - Topic: European Union, grade: 1,0, University of Southern Denmark (Department of Border Region Studies), course: European Border Region Development, language: English, abstract: The last decade saw the establishment of an European Union agency, FRONTEX, whichwas made in charge of the common border security polity established by the Schengen aquiswhich abolished all internal borders for the free movement of persons. Taking thisdevelopment and its results under scrutiny, this paper will try to give an answer to thefollowing research question: How does the actual application of the Schengen aquis byinstitutionalizing it in an agency (FRONTEX) affect or transform the border regimes ofMember States in particular and the European Union in general? The methodology willconsist of an analysis of the legal and deriving organizational design of the agency itself, andas well in describing the operational design of a distinctive FRONTEX deployment. Taking acloser look at the FRONTEX operations HERA I, II and III in particular shall help to define thecharacteristics and implications of its results in promulgating a paradigm which points out tothe result the ongoing transformation of the European border security regime. While being aware of the incentives to create agencies lie in their supposed apolitical natureand ability to maintain policy continuity, which might also apply for the establishment ofFRONTEX as an European Union agency, the notorious and critical acclaim this institutionfaces in the media is another incentive to take as a first step of the analysis a closer look atthe historic and legal roots of the agency its impact on the European border regime so far. Thiswill be followed by a description of the organization of FRONTEX andhow the agency operates in the operations HERA I, II andIII in the years 2006 and 2007.A paradigm will be drawn whichan answer on ifand how the European border regime is to transform.

Seminar paper from the year 2011 in the subject Politics - Topic: European Union, grade: 1,3, University of Flensburg (International Institute for Management), course: External Relations of the European Union, language: English, abstract: In this paper the guiding questions were the following: What Is the EU concept of democracy? Can this supposedly universal norm be promoted by and with the EU external governance scheme? What means are in stock? What has been used? What is used? What are theresults? What can be, what has to be changed? A working definition of democracy is the scale of success which can be applied to the objectives and means in the European Union's foreign policy . The strategies are depicted as well as the level of ambition in democracy promotion of the European Union. The means to realize this ambition are be shown in comparison to the the successes or failures in application. The conflict of priorities in the European Union concerning external relations of the last thirty years is depicted against the backcloth of the normative set of standards drawn from the treaty.

Das zweibändige Werk Leichtbau ist das Standardwerk dieses Arbeitsgebietes für Luft- und Raumfahrttechnik, Fahrzeugbau, Schiffs- und Meerestechnik, Maschinenbau, Fördertechnik, Stahlbau und Fertigungstechnik. Band 2 behandelt Kriterien und Verfahren des Entwerfens und Optimierens, der Auswahl und der beanspruchungsgerechten Gestaltung von Bauteilen und Strukturen auf der technologischen Basis aktueller Bauweisen und Werkstoffe, unter Gesichtspunkten der Zuverlässigkeit und der Schadenstoleranz. In der Neuauflage wurde die Weiterentwicklung der elektronischen Konstruktionssysteme sowie Erfahrungen aus der Konstruktionspraxis berücksichtigt.

Das zweibändige Werk Leichtbau ist das Standardwerk dieses Arbeitsgebietes für Luft- und Raumfahrttechnik, Fahrzeugbau, Schiffs- und Meerestechnik, Maschinenbau, Fördertechnik, Stahlbau und Fertigungstechnik. Band 2 behandelt Kriterien und Verfahren des Entwerfens und Optimierens, der Auswahl und der beanspruchungsgerechten Gestaltung von Bauteilen und Strukturen auf der technologischen Basis aktueller Bauweisen und Werkstoffe, unter Gesichtspunkten der Zuverlässigkeit und der Schadenstoleranz. In der Neuauflage wurde die Weiterentwicklung der elektronischen Konstruktionssysteme sowie Erfahrungen aus der Konstruktionspraxis berücksichtigt.