431 research outputs found
Agrar- und Nährstoffwende : vergessen Transformationen
No full textGreta Sundermann, Melanie Annen, Sophie Hamm, Ariane Krause, Christian von Hirschhausen ; Herausgeberin: Abteilung Analyse, Planung und Beratun
Sky View Factors from Synthetic Fisheye Photos for Thermal Comfort Routing—A Case Study in Phoenix, Arizona
No full textabstract: We generated 5-meter resolution SVF maps for two neighborhoods in Phoenix, Arizona to illustrate fine-scale variations of intra-urban horizon limitations due to urban form and vegetation.Corresponding Author:
Ariane Middel
Arizona State University
[email protected]
On the importance of being earnest about business: overcoming liberal arts students' misconceptions about leadership in corporate change processes
Full text linkUnfortunately, most students leave the university with little knowledge about decision-making in the public sector. Unless they study towards a management degree, most students experience little to no business education in their curricula. As a consequence, student perceptions of the business world are largely shaped by the fads and stereotypes propagated in ubiquitous business journals available in every airport bookstore worldwide. Since business plays an integral role in society, such unfamiliarity with business may have global social consequences. This article illustrates how a liberal arts class focusing on Europe’s social and political integration employs a comprehensive case study about a corporate transformation process to provide students with insights into corporate leadership and strategic decision making. The article describes how, by reading and discussing the case study in conjunction with articles about organizational learning theory, students learn to effectively challenge the myths they hold about heroic leadership and the newest management fads. A key element in the course focuses on the role organizational politics plays in developing and implementing a new vision, a new organizational structure, and a new global strategy. -- Obwohl Unternehmen eine wichtige Rolle in der Gesellschaft spielen, werden Studenten außerhalb der Betriebswirtschaft noch zu selten an Fragestellungen aus dem Bereich der Unternehmenspolitik herangeführt. Wie strategische Entscheidungen in der Wirtschaft getroffen und umgesetzt und neue Visionen und Organisationsstrukturen entwickelt werden, sollte deshalb auch in das Lehrangebot für Geistes- und Sozialwissenschaftler aufgenommen werden. Dieser Artikel zeigt beispielhaft, wie Studenten, im Rahmen einer Lehrveranstaltung an einer US-amerikanischen Universität, anhand einer umfassenden Fallstudie über den Transformationsprozess des Pharmakonzerns Hoechst zum Global Player Aventis zur aktiven Auseinandersetzung mit Veränderungsprozessen in Unternehmen angeregt werden, die ganz anders sind, als die oft plakativen Managementlösungen, die die Business-Literatur dieser Tage zu bieten hat.
Overcoming dangerous learning: the role of critical reflection in cross-cultural interactions
Full text linkRapid globalization has increased the need and opportunity for interactions between people from different cultural backgrounds. Experience is often considered the best teacher and experiences with cross-cultural interactions represent important opportunities to learn to deal with differences. Drawing on a collection of 260 cases, this contribution argues that even when people enter into cross-cultural interactions with the intention of learning new ways of seeing and doing things, they often draw conclusions that make them unreceptive to information that might contradict what they already think. Thus, learning from experience can be dangerous when it inhibits inquiry and closes off new knowledge. This contribution illustrates the kinds of dangerous learning we have encountered in our research and presents strategies of critical self-reflection and interaction to generate shared understandings of situations, desired outcomes, and appropriate actions. -- Erfahrungen gelten als wichtige Lernressource, dieser Beitrag hingegen stellt anhand ausgewählter Fallstudien über interkulturelle Interaktionen dar, wie Erfahrungen dem Lernen auch im Wege stehen können. Die Untersuchung zeigt auf, dass auch Akteure, die sich bewusst in interkulturelle Situationen begeben, um neue Sichtweisen zu erlernen, auf eingeübte Interpretationsmuster und Lösungsansätzen zurückgreifen, sobald kulturelle Situationen ihren eigenen Erfahrungen und Vorstellungen widersprechen. Somit wird das unreflektierte Lernen aus Erfahrungen zu einer gefährlichen Strategie, da es die Überprüfung der Annahmen verhindert und neue Erkenntnisse ausschließt. Die Konsequenzen sind sowohl auf individueller wie auch auf organisationaler Ebene von Bedeutung, da Schlussfolgerungen aus Erfahrungslernen oft unkritisch als handlungsleitend für zukünftige Interaktionen im Organisationsgedächtnis gespeichert werden. Dieser Beitrag verdeutlicht, wie dangerous learning zu Stande kommt und entwickelt interaktive Lernstrategien, um dieser Gefahr entgegenzuwirken.
Delftse chemie levert raketten meer stuwkracht: Geel zout: nieuwe raketbrandstof voor de Ariane 5-raket
No full textOp 15 februari 2003 werd met de Ariane 4 de Intelsat satelliet 907 in een baan om de aarde gebracht. Zowel de Ariane 4 (soms) als 5 werken met ammoniumperchloraat als stuwstof, de standaardraketbrandstof voor civiele als militaire toepassingen. Delftse wetenschappers werken aan een krachtigere brandstof, die 7% meer stuwkracht heeft. Dat betekent dat met dezelfde hoeveelheid brandstof 23% meer lading mee kan, wat een waarde van $ 25 miljoen vertegenwoordigd.Innovation SystemsTechnology, Policy and Managemen
Analysis of the Ariane 62/64 and Vega-C launcher family
No full textAfter the French minister in charge of space matters declared to be open to discuss about Ariane 6 design changes in Mai 2014, several new concepts have been proposed by the industry and analysed by agencies
including DLR during the whole summer 2014. Discussions between the different actors at agency level (ESA, CNES, DLR, ASI) and at industry level led to the development of a new Ariane 6 launcher, with a PHH
architecture, which was officially agreed upon on December 2nd, 2014 in Luxemburg at the ESA council at ministerial level. The present work describes the analyses performed independently within the DLR group XTRAS to critically assess the so-called A62/A64 concepts.
The chosen architecture of Ariane 62/64 is similar to the one of Ariane 5. The first stage uses cryogenic propellants LOX/LH2 and a low cost evolution of Vulcain 2: Vulcain 2.1. It differs from the Ariane 5 EPC by
a smaller propellant loading and separate tanks with the aim of reducing manufacturing costs. The upper stage also uses LOX/LH2 and is propelled by the Vinci engine in a slightly modified configuration: the deployment system of the nozzle is no longer considered and the nozzle is shortened, as cone C has been removed and cone B is directly fixed on cone A. The architecture of the upper stage also considers separate tanks, in order to limit the production cost and to remove difficulties linked to propellant management during ballistic phases, which had been identified as a critical point for the upper stage of Ariane 5 ME. One additional feature of Ariane 6 is that the launcher is modular. It is equipped with 2 or 4 solid rocket
motors for the version named Ariane 62 and Ariane 64 respectively. These motors are named P120C. This motor should also be used as first stage on the next evolution of Vega: Vega-C. Consequently Vega-C is
also shortly considered in the frame of this report. While the first analysis (for instance the sensitivity presented in this report) are based on early concepts of Ariane 62/Ariane 64, more detailed analyses
presented considered Ariane 62/Ariane 64 in its July 2015 status. According to the high level requirements Ariane 62 should be able to launch 5 tons to GTO and Ariane 64 should be able to launch 10.5 tons to
GTO. Note that at the moment this report is being written, the final configuration of Ariane 62/64 is not frozen and might still vary. The cost aspect is also part of the analyses presented in this report. In addition, to trajectory and costs, structural analysis, liquid rocket engine considerations, solid rocket motor design, controllability, transient aerodynamic and thermal aspects are also treated
Negotiating reality as an approach to intercultural competence
Full text linkIn an increasingly global business environment, managers must interact effectively with people who have different values, behavioral norms, and ways of perceiving reality. Many jobs now entail an international dimension, so the need to develop intercultural competences has taken on a greater importance for more people in business than ever before. Intercultural competence is the ability to recognize and use cultural differences as a resource for learning and for generating effective responses in specific contexts. We conceive of this as negotiating reality. The approach draws on concepts from international management, sociology, crosscultural psychology, action science and conflict resolution. -- In einer zunehmend globalisierten Umwelt müssen Führungskräfte immer häufiger mit Menschen aus anderen Kulturen zusammenzuarbeiten, die unterschiedliche Wertevorstellungen haben, verschiedene Verhaltensnormen pflegen und ihre jeweils eigene Wahrnehmung der Realität haben. Damit steigt der Bedarf an interkultureller Kompetenz, der Fähigkeit, kulturelle Unterschiede als Lernressourcen zu erkennen und für die jeweilige Situation adäquate Lösungen zu erarbeiten und einzusetzen. Dieser Beitrag beschreibt einen innovativen Ansatz, den wir negotiating reality nennen, der sich aus unterschiedlichen Theoriebereichen, u.a. dem internationalen Management, der Soziologie, der interkulturellen Psychologie, und der Konfliktforschung speist.
Fluid Structure Interaction at the ARIANE-5 Nozzle section by Advanced Turbulence Models
No full textSubstantial requirements for future rocket technologies are the cost-efficient access to orbit as well as the increase in the system reliability. Concerning these requirements a deeper insight into the unsteady phenomena during the start phase of modern launchers is essential. Especially unsteady side-loads, induced by the interaction of flow separation inside the nozzle, the launcher wake and the nozzle structure will play an important role for the design of future main stage propulsion systems. This so called buffeting coupling phenomenon is one of the main challenges during ascent. For the Ariane-5 configuration unsteady Detached Eddy Simulations were carried out under transonic wind tunnel conditions and validated with experimental data. For this configuration also a first coupled simulation of the flow field and the original nozzle structure of an Ariane-5 wind tunnel model is carried out to investigate resonances and loads on the nozzle
Land Grabbing and Home Country Development : Chinese and British Land Acquisitions in Comparative Perspective /
No full textBetween 2000 and 2016, China and the UK acquired large areas of land through investment projects in Sub-Saharan Africa. Illustrated by numerous rich and nuanced empirical accounts of such projects, Ariane Goetz explains the global phenomenon of 'land grabbing' from the perspective of two investor countries. She reflects on Chinese and British public policy, state-society relations, national developmental contexts, ideologies, and international relations and thereby gives insights into the political economies that enable these investments as well as the development ambitions and institutionalized paradigms of which they form a part.Between 2000 and 2016, China and the UK acquired large areas of land through investment projects in Sub-Saharan Africa. Illustrated by numerous rich and nuanced empirical accounts of such projects, Ariane Goetz explains the global phenomenon of 'land grabbing' from the perspective of two investor countries. She reflects on Chinese and British public policy, state-society relations, national developmental contexts, ideologies, and international relations and thereby gives insights into the political economies that enable these investments as well as the development ambitions and institutionalized paradigms of which they form a part.Online resource; title from PDF title page (publisher's Web site, viewed 23. Mai 2019).Includes bibliographical references (pages [305]-368).Added to collection customer.56279.
Development of cryogenic upper-stage concepts for future European launchers after Ariane 6
No full textThis thesis work on the development of concepts for future European launchers’ cryogenic upper
stages proposes three conceptual architectures which are modelled in an iterative fashion. The
upper stage concepts are designed for use in combination with the reusable main stage concept
RLVC4-III-B by the German Aerospace Center, which is a winged first stage for horizontal in-air
recovery with 340 tons of ascent propellant and 59.5 m in length. The upper stage concepts are
(1) single-staged with carbon-fibre structures, (2) two-staged with metallic structures and (3) twostaged with carbon-fibre structures. The design payload target is at least 7.5 tons to GTO.
A variety of potential innovation approaches aimed at different sub- or primary components of
cryogenic upper stages is presented towards their technological readiness. Promising and realistic
innovations, which are expected to have a measurable and positive impact on an architectures’
mass, are included in specific upper stage architectures and accounted for throughout the modelling
process.
The architectures’ performance, structural and aerodynamic analysis is described and discussed.
The models are initially foreseen to have ratios of ascent propellant to wet stage mass of (1) 89 %,
(2) 85 % and (3) 87 %. The final, validated models show propellant ratios of (1) 88 % , (2) 87.3 %
and (3) 87.2 % after consideration of the designated innovation approaches. The second concept,
which shows a large deviation from the expected propellant ratio for which it was pre-dimensioned,
reaches a low dry mass due to the implementation of hydrogen tank self-pressurization, an advanced
propellant management device, wireless avionics and Aerogel as insulation material.
Ascent simulation and optimization has been performed for the upper stage concepts in combination with the reusable RLVC4-III-B as main stage. All launch arrangements have gross lift-off
masses below 600 tons. The integrated systems show payload performances of (1) 10.4 tons, (2)
19.3 tons and (3) 18.5 tons to GTO with a perigee of 250 km. The second stages of the two-staged
architectures, which carry propellant masses similar to the Ariane 6 upper stage, are additionally
simulated in combination with the Ariane 6 main stage and 4 boosters, reaching (2) 24.4 % and (3)
28.9 % higher GTO payload than with the nominal upper stage.
The concepts developed in this thesis are optimized towards minimum total lift-off mass with the
RLVC4-III-B as reference main stage, while cost and manufacturability are disregarded. Basic stage
dimensions and architectural decisions are frozen early on in the iterative design process. Taking
these aspects into account in an extensive trade-off analysis would increase the relevance of the
development of modern launcher stage concepts and is proposed as potential future work
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