University of Stuttgart

About: University of Stuttgart is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Laser & Finite element method. The organization has 27715 authors who have published 56370 publications receiving 1363382 citations. The organization is also known as: Universität Stuttgart.

Early science with sofia, the stratospheric observatory for infrared astronomy

Abstract: The Stratospheric Observatory For Infrared Astronomy (SOFIA) is an airborne observatory consisting of a specially modified Boeing 747SP with a 2.7 m telescope, flying at altitudes as high as 13.7 km (45,000 ft). Designed to observe at wavelengths from 0.3 μm to 1.6 mm, SOFIA operates above 99.8% of the water vapor that obscures much of the infrared and submillimeter. SOFIA has seven science instruments under development, including an occultation photometer, near-, mid-, and far-infrared cameras, infrared spectrometers, and heterodyne receivers. SOFIA, a joint project between NASA and the German Aerospace Center Deutsches Zentrum fur Luft und-Raumfahrt, began initial science flights in 2010 December, and has conducted 30 science flights in the subsequent year. During this early science period three instruments have flown: the mid-infrared camera FORCAST, the heterodyne spectrometer GREAT, and the occultation photometer HIPO. This Letter provides an overview of the observatory and its early performance.

Sequence of Tense and Temporal de re

Abstract: L'A. examine deux theories du temps en contexte intensionnel, une theorie extensionnelle et une theorie intensionnelle. La premiere soutient que le temps a le meme sens, que le contexte soit intensionnel ou extensionnel, c'est-a-dire que rien de particulier ne caracterise la semantique des temps dans les phrases enchâssees. L'A. propose une autre theorie et tente de montrer que la sequence de temps ne peut etre decrite uniquement en termes de syntaxe de surface. Il propose une semantique des temps ou les temps enchâsses dans des contextes intensionnels agissent en meme temps sur plusieurs relations temporelles

Thermoelectrics: From history, a window to the future

Abstract: Thermoelectricity offers a sustainable path to recover and convert waste heat into readily available electric energy, and has been studied for more than two centuries. From the controversy between Galvani and Volta on the Animal Electricity, dating back to the end of the XVIII century and anticipating Seebeck’s observations, the understanding of the physical mechanisms evolved along with the development of the technology. In the XIX century Orsted clarified some of the earliest observations of the thermoelectric phenomenon and proposed the first thermoelectric pile, while it was only after the studies on thermodynamics by Thomson, and Rayleigh’s suggestion to exploit the Seebeck effect for power generation, that a diverse set of thermoelectric generators was developed. From such pioneering endeavors, technology evolved from massive, and sometimes unreliable, thermopiles to very reliable devices for sophisticated niche applications in the XX century, when Radioisotope Thermoelectric Generators for space missions and nuclear batteries for cardiac pacemakers were introduced. While some of the materials adopted to realize the first thermoelectric generators are still investigated nowadays, novel concepts and improved understanding of materials growth, processing, and characterization developed during the last 30 years have provided new avenues for the enhancement of the thermoelectric conversion efficiency, for example through nanostructuration, and favored the development of new classes of thermoelectric materials. With increasing demand for sustainable energy conversion technologies, the latter aspect has become crucial for developing thermoelectrics based on abundant and non-toxic materials, which can be processed at economically viable scales, tailored for different ranges of temperature. This includes high temperature applications where a substantial amount of waste energy can be retrieved, as well as room temperature applications where small and local temperature differences offer the possibility of energy scavenging, as in micro harvesters meant for distributed electronics such as sensor networks. While large scale applications have yet to make it to the market, the richness of available and emerging thermoelectric technologies presents a scenario where thermoelectrics is poised to contribute to a future of sustainable future energy harvesting and management. This work reviews the broad field of thermoelectrics. Progress in thermoelectrics and milestones that led to the current state-of-the-art are presented by adopting an historical footprint. The review begins with an historical excursus on the major steps in the history of thermoelectrics, from the very early discovery to present technology. Then, the most promising thermoelectric material classes are discussed one by one in dedicated sections and subsections, carefully highlighting the technological solutions on materials growth that have represented a turning point in the research on thermoelectrics. Finally, perspectives and the future of the technology are discussed in the framework of sustainability and environmental compatibility. An appendix on the theory of thermoelectric transport in the solid state reviews the transport theory in complex crystal structures and nanostructured materials.

Corporate Social Responsibility in Business-to-Business Markets : How Organizational Customers Account for Supplier Corporate Social Responsibility Engagement

Abstract: Despite the high relevance of corporate social responsibility (CSR) in current business practice and the considerable research on CSR outcomes in consumer markets, investigations of its influence on organizational business relationships are scarce. Relying on instrumental stakeholder theory, the authors develop and empirically test a framework of the influence of a supplier's CSR engagement on organizational customer outcomes. Findings from an examination of 200 cross-industry supplier–customer dyads reveal positive effects of two facets of a supplier's CSR efforts on customer loyalty through distinct mechanisms. Business practice CSR fosters customers' trust, whereas philanthropic CSR strengthens customer–company identification. The authors distinguish a supplier's actual CSR engagement and customers' perception of these CSR activities. In addition, they consider central contingency factors reflecting uncertainty and dependence in business-to-business relationships that determine the effectiveness of CSR.