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Luneburg, Germany

The Leuphana University Lüneburg in Lüneburg, Germany, was founded in 1946 as a college of education and, since 2007, has offered a unique, Germany-wide, study and university model. It is designated as a 'foundation under public law'.The name Leuphana is derived from an ancient settlement on the Elbe river, that was mentioned in the geographical world atlas by Ptolemy in the 2nd century.The Leuphana College concentrates its bachelor degree studies into eight departments and two teacher training courses. In 2008 a graduate college was opened that integrates master degree and doctorate programmes. In addition there is a pan-departmental research centre and a professional school for advanced study courses like business cooperation. Wikipedia.

Mercorelli P.,Luneburg University
IEEE Transactions on Industry Applications | Year: 2012

Camless internal combustion engines offer improvements over traditional engines in terms of increased torque performance and fuel economy and of decreased emissions and pumping losses. The main goal of this project is to replace the camshaft system with electromagnetic actuators to control the intake and exhaust valves of internal combustion engines. Theoretically, electromagnetic valve actuators provide, with their control flexibility, the highest potential for improved efficiency. Sensorless control is one of the most important issues in implementations of this new technology. The main contribution of this paper is the proposal of a hysteresis hybrid observer to be applied for achieving a sensorless control. This observer consists of a combination of an extended Kalman filter with a hybrid automation. The proposed state-observation structure avoids bulky and complicated measurement systems, which is an important advancement for real-world applications. The introduced method is quite general and could be applied to other problems in which it is not feasible or affordable to obtain position and velocity measurements. In fact, in application with synchronous machines, such kind of an observer can represent a general approach to obtain a sensorless control. The proposed hysteresis strategy not only avoids chattering problems when the velocity is close to zero but also allows the use of unobservable sets and sets in which the observability level is too low to guarantee sufficient variation in the Kalman gains. The proposed structure consists of two models, each model containing two embedded switching conditions. The current is measured, and the position and the velocity of the electromagnetic valve are estimated. The effectiveness of the proposed method is demonstrated using measured data acquired from an experimental setup based on an innovative electromagnetic valve actuator. © 1972-2012 IEEE. Source

Brittain C.,Luneburg University
Proceedings. Biological sciences / The Royal Society | Year: 2013

In diverse pollinator communities, interspecific interactions may modify the behaviour and increase the pollination effectiveness of individual species. Because agricultural production reliant on pollination is growing, improving pollination effectiveness could increase crop yield without any increase in agricultural intensity or area. In California almond, a crop highly dependent on honey bee pollination, we explored the foraging behaviour and pollination effectiveness of honey bees in orchards with simple (honey bee only) and diverse (non-Apis bees present) bee communities. In orchards with non-Apis bees, the foraging behaviour of honey bees changed and the pollination effectiveness of a single honey bee visit was greater than in orchards where non-Apis bees were absent. This change translated to a greater proportion of fruit set in these orchards. Our field experiments show that increased pollinator diversity can synergistically increase pollination service, through species interactions that alter the behaviour and resulting functional quality of a dominant pollinator species. These results of functional synergy between species were supported by an additional controlled cage experiment with Osmia lignaria and Apis mellifera. Our findings highlight a largely unexplored facilitative component of the benefit of biodiversity to ecosystem services, and represent a way to improve pollinator-dependent crop yields in a sustainable manner. Source

Richter M.,Luneburg University
Renewable Energy | Year: 2013

The transformation of the energy industry towards a more sustainable production of electricity increases the importance of distributed generation from renewable sources such as solar photovoltaic (PV). German utilities have largely failed to benefit from this development and lost 97% of the distributed PV generation market to investors from outside the electric power industry. Recent studies indicate that utilities have to react to prevent revenue erosion and loss of profits. This study identifies threats and opportunities of distributed PV generation for utilities based on a series of interviews with German utility managers. The key finding is that utilities do not perceive distributed PV as a threat to their current business models nor do they see it as a potential market for them. Relating these findings to the existing literature on transformation processes in other industries leads to the conclusion that the solution for utilities lies in changing their perspective on distributed PV. Utilities could greatly benefit if they did not treat PV as just another source of electricity generation in competition with traditional sources (as they do today), but as a strategic gateway into the emerging distributed generation and service market. Distributed PV could function as a basis for further business model innovation in new growth markets such as energy efficiency and distributed storage. Specific recommendations are provided and a modular value proposition is suggested to help utilities to turn distributed PV from a threat into an attractive business opportunity. © 2013 Elsevier Ltd. Source

Urban B.,Luneburg University | Bigga G.,University of Tubingen
Journal of Human Evolution | Year: 2016

The Pleistocene sequence of Schöningen provides a key link between unglaciated and glaciated areas in western Central Europe and is an important point of reference for the subdivision of the glaciated late Middle Pleistocene. This locality yields palaeoecological and geological evidence of at least four interglacial periods prior to the Holocene and younger than the Elsterian glaciation. The Pleistocene deposits at Schöningen are valuable archives of climate, landscape, and human evolution, containing outstanding information on past environmental changes and human adaptation. This paper presents paleoenvironmental and biostratigraphical results from the Middle Pleistocene archeological lakeshore site of Schöningen, focusing on the so-called reference profile Schöningen 13 II of 2003. We discuss the lithological, palynological, and macrobotanical evidence and present a revised subdivision and reinterpretation of late phases of the Reinsdorf Interglacial. © 2015 Elsevier Ltd. Source

Richter M.,Luneburg University
Renewable and Sustainable Energy Reviews | Year: 2012

The transformation of today's electric power sector to a more sustainable energy production based on renewable energies will change the structure of the industry. Consequently, utilities as the major stakeholders in this transformation will face new challenges in their way of doing business. They will have to adapt their business models to remain competitive in the new energy landscape. The present review of business model literature shows that two basic choices exist: utility-side business models and customer-side business models. The two approaches follow a very different logic of value creation. While the former is based on a small number of large projects, the latter is based on a large number of small projects. The article reveals that blueprints for utility-side business models are available, whereas customer-side business models are in an early stage of development. Applying the business model framework as an analytical tool, it is found that existing utility-side business models comprise a series of advantages for utilities in terms of revenue potential and risk avoidance. This study provides new insights about why utilities will favor utility-side business models over customer-side business models and why they also should engage in customer-side business models in their quest for more sustainable future business models. © 2012 Elsevier Ltd. All rights reserved. Source

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