Optimal Dynamic Control of Visitors and Endangered Species in a National Park

To enable visitors to enjoy nature while protecting endangered species is the key challenge for national parks around the world. In our optimal dynamic control model, a park management maximizes tourism revenues and conservation benefits net of control costs by choosing optimal dynamic levels of conservation and visitor management. The optimization is constrained by an extended food chain model representing species-habitat-visitor interactions. We illustrate for a game bird in an Alpine national park that ecotourism can indeed lead to ecosystem degradation when the park management is more concerned about increasing tourism revenues than about achieving the conservation target and if the endangered species is unknown to most visitors. If, however, the park management is well aware of the potentially negative consequences of ecotourism and hence cares for species conservation, limited ecotourism can provide funding for species conservation which ensures population levels above the uncontrolled steady state.     

Innovation networks in eastern germany — a still under-utilised potential for human capital formation in the region

Conclusion In regard to easing the shortage of skilled labour the networking of protagonists in the InnoRegios is not, as yet, sufficient on the whole. In particular, companies are not sufficiently involved. The potential for networking to close the human capital gap is apparently still not being fully utilised in the innovation networks. One explanation could be the low implementation rate of the planned basic and advanced training projects so far. It must also be borne in mind that companies could assess the risks of cooperation as greater than the possible advantages, as they are competing on the labour market. Another explanation is that the participants in the networks expect technological projects to offer greater success.     

Profit maximization mitigates competition

Summary We consider oligopolistic markets in which the notion of shareholders' utility is well-defined and compare the Bertrand-Nash equilibria in case of utility maximization with those under the usual profit maximization hypothesis. Our main result states that profit maximization leads to less price competition than utility maximization. Since profit maximization tends to raise prices, it may be regarded as beneficial for the owners as a whole. Moreover, if profit maximization is a good proxy for utility maximization, then there is no need for a general equilibrium analysis that takes the distribution of profits among consumers fully into account and partial equilibrium analysis suffices.We wish to thank Hildegard Dierker and Nina Maderner for many helpful comments. This research was partially supported by the Danish Social Science Research Council. E. Dierker is grateful to the Department of Economics, University of Copenhagen, for its outstanding hospitality. B. Grodal appreciates the support from the Department of Economics, University of Vienna.     

Hohe Sterblichkeit

Diagnostik und Therapie der Lungenentzündung - Verschiedene Erreger wie Viren, Bakterien oder Pilze k?nnen das Lungengewebe angreifen und urs?chlich für eine Pneumonie sein. Daraus resultiert, dass es für die verschiedenen Formen der Pneumonie und auch verschiedene Behandlungsans?tze gibt.     

Womit befassen sich kommunikationswissenschaftliche Abschlussarbeiten?

Transfer is an e-journal of the German academic association of journalism and communication (DGPuK), publishing abstracts of excellent theses in communication in German speaking countries. Since 1999, more than 1.000 abstracts have been collected. This article presents a content analysis of all abstracts published between 1999 and 2008 (n?=?1.056). The objective is to contribute to the ongoing debate about the identity of German speaking communication research and thus adding results to existing studies on journal publications and surveys among researchers. The content analysis examines the issues, the media analyzed, the use of theoretical and empirical approaches and the dominance of public communication as issue – as compared to interpersonal communication – of the studies, based on the abstracts published. Results show that the issues analyzed and the methods applied have not changed much over the years. A somehow alarming result is the fact that only very few abstracts explicitly refer to a theory. This raises the question of the deceasing relevance of theories in today’s communication research.     

A test of the HRM model: good for employers and employees

Some of the assumptions made by the proponents of the strong version of HRM are tested, using social identity theory and group processes. In particular, the author explores the proposed link between the HRM characteristics integration, commitment, quality and flexibility and examines their relationships to employee satisfaction, intention to stay and organisational performance. Based on a survey conducted among bank employees, correlational and multiple regression analysis, both at individual and at branch level, confirm the connection between integration, commitment, quality and flexibility. Commitment emerges as the central variable. It is closely related to work satisfaction and intention to stay and, most importantly, makes a significant contribution to branch performance.     

Die Auswirkungen des EEG auf das Energiesystem Deutschlands – Eine Betrachtung mit dem Energiesystemmodell TIMES-D

In Germany, the electricity generation from renewable energy has been promoted since the year 2000 by a feed-in tariff system, the Renewable Energy Sources Act (EEG). This article evaluates the long-term impact of the German feed-in tariffs on the development of the German energy system with the help of the energy system model TIMES-D. In the model-based analysis, both the payment side (i.e. the tariffs) and the cost side (i.e. the EEG apportionment) are taken into consideration. Through the promotion of the feed-in tariff system—in combination with the European Emission Trading Scheme (ETS)—the use of renewable energies in electricity generation in Germany rises considerably such that renewable energy sources account for almost 40% of total gross electricity consumption in 2030. Accordingly, until 2020 total EEG fee payments as well as the EEG apportionment increase significantly. The impact of the feed-in tariff system on final electricity demand is, however, relatively small. Alternative scenario settings show that the expansion of the renewable electricity generation through the feed-in tariff system clearly exceeds the development which would occur when trying to reach the reduction targets of the ETS in a cost-efficient way.