Single-photon generation and simultaneous observation of wave and particle properties

We describe an experiment that generates single photons on demand and measures properties accounted to both particle- and wave-like features of light. The measurement is performed by exploiting data that are sampled simultaneously in a single experimental run.Comment: The following article has been submitted to Proceedings of "Foundations of probability and physics-3", Vaxjo, Sweden 2004. After it is published, it will be found at http://proceedings.aip.org/ . 1 Reference was added in version

A Nordic Union? A review of the Gunnar-Wetterberg-proposal

Aim of this paper is a review of Gunnar Wetterbergs proposal of establishing a Nordic Union between the countries of the Nordic region. Based from this concept and its origin in the contemporary context of Regionalism, European Integration and Nordism a Narratives Policy Analysis will be provided. Intentions, backgrounds and the time of this draft idea are for this purpose to be set in relation to the topic of Nordic co-operation within and beyond the European Union. Major lines in the public debate on this issue as well as its impacts have to be summarized and as far as possible practical reasons and arguments for and against an institutionalized realization of such a Nordic federation state will be discussed

Labour hoarding in Germany: Employment effects of short-time work during the crises

During the crisis (2008-09) Germany experienced a huge decrease in GDP. Employment, however, remained surprisingly stable. A whole strand of literature has aimed at quantifying the contribution of short-time work to the German labour market miracle. In the course of this literature we estimate the treatment effect of short-time work on employment at establishment level using a dynamic propensity score matching approach. The analysis is based on data from the IAB Establishment Panel combined with administrative data on short-time work establishments from the Federal Employment Agency. Our results do not indicate any treatment effect of short-time work on employment.Während der Wirtschaftskrise (2008-09) erlebte auch Deutschland einen starken Rückgang des Bruttoinlandsprodukts. Die Beschäftigung blieb jedoch erstaunlich stabil. Seitdem zielen viele Publikationen darauf, den Anteil des arbeitsmarktpolitischen Instruments Kurzarbeit am sogenannten deutschen Arbeitsmarktwunder zu quantifizieren. Im Zuge dieser Literatur schätzen wir die kausale Wirkung von Kurzarbeit auf das Beschäftigungsniveau von Betrieben und nutzen dafür den Propensity Score Matching Ansatz. Die Analyse basiert auf Daten des IAB-Beschäftigtenpanels kombiniert mit administrativen Daten der Bundesagentur für Arbeit zur tatsächlichen betrieblichen Inanspruchnahme von Kurzarbeit. Unsere Ergebnisse geben keinerlei Hinweise auf eine kausale Wirkung von Kurzarbeit auf das betriebliche Beschäftigungsniveau

Measuring preferences on environmental damages in LCIA. Part 2: choice and allocation questions in panel methods

Background, aim, and scope: Within life cycle impact assessment (LCIA), ‘panel methods' has become a common term to denominate methods that elicit and measure stakeholders' stated preferences on environmental impact categories. Such panel procedures use different question formats to elicit information on weighting across impact categories from the stakeholders. The two most frequently used question formats are score allocation and choice between alternatives. The differences between these two question formats were analyzed in order to give advice on how to frame future panel procedures. Materials and methods: A choice-based weighting procedure (choice experiment) for the three damage categories of human health, ecosystems quality, and resources was developed and executed. A logistic regression model was applied in order to estimate the weighting factors for the polled sample. Results from this choice-based procedure were compared to the results from an allocation-based procedure described in part 1 of this paper. Results: When weighting factors are elicited by score allocation questions, panelists tend to distribute the scores more equally. A factor of 1.5 between the least and the most weighted damage category was found. Weighting factors from a choice experiment were more spread, i.e., the most important category was weighted considerably higher, whereas the other two categories were weighted less. Thus, for the choice experiment, the range between the most and the least weighted categories was considerably bigger—by about a factor of 4. Discussion: A comparison of the two procedures revealed that the weighting of environmental damage categories is considerably influenced by the question of format. The reason for these variations may be different cognitive routines that are applied. In addition, several advantages and shortcomings of choice experiments are discussed. Conclusions: The developed, choice-based procedure provided meaningful results. Thus, choice experiments, often used for the monetary valuation of environmental goods, can also be applied in LCIA to elicit nonmonetary weighting factors. Recommendations and perspectives: Choice experiments form a new interesting approach for weighting procedures in the future as they have some advantages over the often used score allocation methods. They are simple and more realistic than other procedures, as panelists have practiced in choice tasks from everyday life. We, therefore, recommend such choice-based procedures for future panel studie

Assessment of land use impacts on the natural environment: Part 2: Generic characterization factors for local species diversity in Central Europe

Goal, Scope and Background: Land use is an economic activity that generates large benefits for human society. One side effect, however, is that it has caused many environmental problems throughout history and still does today. Biodiversity, in particular, has been negatively influenced by intensive agriculture, forestry and the increase in urban areas and infrastructure. Integrated assessment such as Life Cycle Assessment (LCA), thus, incorporate impacts on biodiversity. The main objective of this paper is to develop generic characterization factors for land use types using empirical information on species diversity from Central Europe, which can be used in the assessment method developed in the first part of this series of paper. Methods: Based on an extensive meta-analysis, with information about species diversity on 5581 sample plots, we calculated characterization factors for 53 land use types and six intensity classes. The typology is based on the CORINE Plus classification. We took information on the standardized α-diversity of plants, moss and mollusks into account. In addition, threatened plants were considered. Linear and nonlinear models were used for the calculation of damage potentials (EDP S). In our approach, we use the current mean species number in the region as a reference, because this determines whether specific land use types hold more or less species diversity per area. The damage potential calculated here is endpoint oriented. The corresponding characterization factors EDP S can be used in the Life Cycle Impact Assessment as weighting factors for different types of land occupation and land use change as described in Part 1 of this paper series. Results: The result from ranking the intensity classes based on the mean plant species number is as expected. High intensive forestry and agriculture exhibit the lowest species richness (5.7-5.8 plant species/m2), artificial surfaces, low intensity forestry and non-use have medium species richness (9.4-11.1 plant species/m2) and low-intensity agriculture has the highest species richness (16.6 plant species/m2). The mean and median are very close, indicating that the skewedness of the distribution is low. Standard error is low and is similar for all intensity classes. Linear transformations of the relative species numbers are linearly transformed into ecosystem damage potentials (EDP linear S ). The integration of threatened plant species diversity into a more differentiated damage function $$EDP_{linear}^{S_{total} }$$ makes it possible to differentiate between land use types that have similar total species numbers, but intensities of land use that are clearly different (e.g., artificial meadow and broad-leafed forest). Negative impact values indicate that land use types hold more species per m2 than the reference does. In terms of species diversity, these land use types are superior (e.g. near-to-nature meadow, hedgerows, agricultural fallow). Discussion: Land use has severe impacts on the environment. The ecosystem damage potential EDP S is based on assessment of impacts of land use on species diversity. We clearly base EDP S factors on α-diversity, which correlates with the local aspect of species diversity of land use types. Based on an extensive meta-analysis of biologists' field research, we were able to include data on the diversity of plant species, threatened plant species, moss and mollusks in the EDP S. The integration of other animal species groups (e.g. insects, birds, mammals, amphibians) with their specific habitat preferences could change the characterization factors values specific for each land use type. Those mobile species groups support ecosystem functions, because they provide functional links between habitats in the landscape. Conclusions: The use of generic characterization factors in Life Cycle Impact Assessment of land use, which we have developed, can improve the basis for decision-making in industry and other organizations. It can best be applied for marginal land use decisions. However, if the goal and scope of an LCA requires it this generic assessment can be complemented with a site-dependent assessment. Recommendations and Perspectives: We recommend utilizing the developed characterization factors for land use in Central Europe and as a reference methodology for other regions. In order to assess the impacts of land use in other regions it would be necessary to sample empirical data on species diversity and to develop region specific characterization factors on a worldwide basis in LCA. This is because species diversity and the impact of land use on it can very much differ from region to regio

Gemeindesteuern der Zinsbereinigten Gewinnsteuer

Ein rationales Steuersystem sollte sich durch Finanzierungs-, Investitions- und Rechtsformneutralität auszeichnen und das Wirtschaftswachstum möglichst nicht negativ beeinträchtigen. Ferner muss eine Steuererhebung seitens der Finanzverwaltung und eine Steuerbefolgung durch die Steuerpflichtigen unter administrativ vertretbarem Aufwand möglich sein. Das geltende deutsche Steuersystem vermag diese Anforderungen auch nach der jüngsten Unternehmensteuerreform von 2008 nicht zu erfüllen. Mit dem Reformvorschlag 'Zinsbereinigte Gewinnsteuer' (ZGS) sollen diese Mängel beseitigt werden. Gemeindesteuern sind ein wichtiger Bestandteil des Steuersystems und bedürfen der besonderen Beachtung im Rahmen einer konsistenten Steuerreform. Insbesondere dürfen kommunale Steuern nicht die ökonomische Wirkung der föderalen konterkarieren. Die Reform der Gemeindefinanzierung wird hier vor dem Hintergrund und im Kontext der Reform der föderalen Ertragssteuern behandelt. Die ertragssteuerliche Umsetzung der ZGS bildet dabei die Grundlage für die Implementierung ihrer Gemeindesteuern. Zur Gemeindefinanzierung aus Steuermitteln sieht der Reformvorschlag ZGS vier Hauptsäulen vor. Eine betriebsstättenbezogene kommunale Gewinnsteuer mit zinsbereinigter Bemessungsgrundlage bildet die erste zentrale Säule. Sie wird von einer an der Einkommensteuer anknüpfenden kommunalen Bürgersteuer flankiert, die den Wohnortgemeinden zugute kommt. Zur Deckung von Finanzierungslücken wird ein neuer Anteil an der Umsatzsteuer eingeführt, der den einzelnen Gemeinden nach Maßgabe eines Verteilungsschlüssels zugewiesen wird. Eine vierte Säule der Gemeindefinanzierung stellt eine reformierte Grundsteuer dar. Teil 1 dieser Arbeit beschreibt die ZGS zunächst in ihren Grundzügen. Vor dem Hintergund der Kriterien für ein rationales kommunales Steuersystem wird die Gemeindeebene des Reformvoschlages entwickelt. Die Umsetzung der kommunalen Gewinnsteuer erfolgt auf der Basis der existierenden Gewerbesteuer, die zu einer Gemeindewirtschaftssteuer fortentwickelt wird. Auf systematisch notwendige Änderungen in der Bemessungsgrundlage wird dabei detailliert eingegangen. Die kommunale Bürgersteuer wird bezüglich ihrer Bemessungsgrundlage und Tarifstruktur konzeptionell beschrieben. Merkmale eines Verteilungsschlüssels für den neuen kommunalen Anteil an der Umsatzsteuer werden entwickelt und ökonomisch begründet. Ferner wird auf die Sinnhaftigkeit einer revitalisierten Grundsteuer als Bestandteil des kommunalen Steuersystems hingewiesen. Teil 2 beinhaltet Rechtsgrundlagen in Form von Änderungsgesetzen. Zwecks besserer Lesbarkeit werden außerdem die geänderten Rechtsnormen im Kontext des jeweiligen vollständigen Gesetzes abgedruckt. Die steuerrechtliche Implementierung der ZGS erfolgt für die kommunale Gewinnsteuer und den Verteilungsschlüssel des kommunalen Anteils an der Umsatzsteuer. Noch nicht Gegenstand der gesetzlichen Umsetzung sind die kommunale Bürgersteuer und die revitalisierte Grundsteuer

Measuring Preferences on Environmental Damages in LCIA. Part 1: Cognitive Limits in Panel Surveys (9 pp)

-: Part 1: Cognitive Limits in Panel Surveys · Part 2: The Question Format in Panel Surveys This series of two papers discusses the elicitation of weights for damage categories in LCIA with the aid of panel surveys. The papers focus especially on methodological aspects in panel surveys. Part 1 discusses potential cognitive limits of the panel members to understand the reference that is weighted. Part 2 focuses on the influence of the question format and compares results from two different weighting tasks: discrete choice (between alternatives) and score allocation. Goal, Scope and Background: The weighting of environmental impacts and damages on the safeguard subjects Human Health, Ecosystems, and Resources is a significant step of full aggregated LCIA. Panel surveys have become a common approach in LCIA research to investigate the preferences of stakeholders on environmental impacts and damages. Despite the numerous studies, the knowledge on how to elicit reliable weights is still poor and inconsistent. We present a questionnaire study with 58 environmental science students to investigate so-called framing effects in panel surveys. Main Features: The study investigates the significance of different framings, which were provided by three references. In addition, the significance of quantitative information provided in the questionnaire is tested. The references are (a1) safeguard subjects without specified additional information, (a2) damages in Europe as they are perceived by the panelist, and (a3) quantified scenarios derived from Eco-indicator99. All participants ranked and rated the importance of the safeguard subjects three times, once within each reference system. According to a test-of-scope study, quantitative information given to the panelist was varied. One level (b1) included data from the Ecoindicator99 methodology, whereas the other group (b2) received data with significantly higher Human Health damages and lower Ecosystem damages, ceteris paribus. This design allows testing the influence of quantitative data on the rating. Results: The weighting of the safeguard subjects (a1) reveals that Human Health is considered a slightly more important safeguard subject than Ecosystems. However, both are judged to be significantly more important than Resources. This picture changes for the references (a2) and (a3) where damages were weighted. For both references, the respondents rated damages to Ecosystems as most important followed by Resources and Human Health, showing by far the lowest weights. Therefore, the framing of the reference that was weighted played a significant role. The ratings of the subgroups (b1) and (b2) did not differ with respect to the importance of damages, though substantially different quantitative information was given. Conclusion and Outlook: The participants of the study were obviously insensitive with respect to quantitative information provided. This raises three questions, which are discussed. What is the mental model upon which respondents base their beliefs and values? Can we expect that 'more sophisticated' subjects would respond differently? Which prerequisites should an empirical weighting procedure fulfill in order to incorporate numerical data? We propose different approaches for future procedures in order to accurately analyze these question