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Im Rahmen dieser Studie soll ermittelt werden, welche Bedeutung sowohl quantitative, als auch qualitative Kriterien für die Beurteilung von Risiken in den Akteursgruppen Manager, Verwaltungsangehörige, Experten und Laien einnehmen. Bei der Beurteilung von Umweltrisiken spielen neben quantitativen Beurteilungskriterien (z.B. der Schadenswahrscheinlichkeit) auch qualitative Kriterien (z.B. die ausgelösten Emotionen) eine zentrale Rolle, wie insbesondere die Ergebnisse der psychometrischen Risikoforschung zeigen.
Im Rahmen dieser Studie soll ermittelt werden, welche Urteilsmodelle bzw. -konzepte Manager, Verwaltungsangehörige, Experten und Laien zur Bewertung von Risiken verwenden. Dazu wird eine Untersuchungsmethode, die Conjoint-Analyse, verwendet, die mit spezifischen Problemen der psychometrischen Risikoforschung besser umzugehen vermag und die u.E. noch nicht in der Risikowahrnehmungsforschung eingesetzt wurde. Inhalt: Ziel der Untersuchung Fragestellung Die Conjoint-Analyse Das Design der Studie Stichprobe und Datenerhebungsprozedur Ergebnisse: -Risikoakzeptanzwerte -Entscheidungswichtigkeit der Risiken -Gruppenanalyse
Gegenstand der Studie sind Risikobewertungen als Teil von Entscheidungen über die Akzeptanz von Risiken. Dabei handelt es sich nicht nur um einen Problembereich für Experten. Auch die Wirtschaft, die Verwaltung, die Politik und die interessierte Öffentlichkeit ist an solchen Entscheidungen beteiligt. Inhalt: Gegenstand der Studie Ziele der Studie Theoretischer Rahmen Hypothesen Methodische Grundlagen Ergebnisse -Das Kategorienschema -Häufigkeit und Inhalte kognitiver Kategorien: Zentrale Kategorien -Graphische Auswertung: Hierarchical Value Maps: HVM für gentechnisch verändertes Getreidesaatgut, HVM für Kunststoffzusatz, HVM für neues Arzneimittel, Gesamtanalysen
Die vorliegende Untersuchung basiert auf einer Befragung von insgesamt 93 Unternehmen aus den Regionen Potsdam, Berlin und Chemnitz. Die Interviews wurden im Zeitraum Mai/Juni 1996 durchgeführt und dauerten ca. 1 Stunde. Im Mittelpunkt der Befragung standen die Themenbereiche: ökologische Betroffenheit, Einstellung zum Umweltschutz, Markt- und Wettbewerbsbedingungen des betrieblichen Umweltschutzes, Umfang und Intensität betrieblicher Maßnahmen zum Umweltschutz sowie Verhaltensbarrieren. Als Interviewpartner standen in der Mehrzahl der befragten Unternehmen die Geschäftsführer oder Umweltbeauftragte bzw. andere Personen in Führungspositionen zur Verfügung. Zum überwiegenden Teil waren die von uns befragten Unternehmer selbst Eigentümer der Unternehmung. Die befragten Unternehmen gehören überwiegend dem Konsumgütersektor (44%) an. Ein Drittel der Unternehmen stammt aus dem Investitionsgütersektor (33%). Der Dienstleistungssektor ist mit lediglich 23% in der Stichprobe vertreten. Insgesamt bildet die Stichprobe ein breites Branchenspektrum ab, wenn auch die Geschäftsbereiche Maschinenbau und Anlagen, bedingt durch ihre starke Präsenz im Raum Chemnitz, deutlich überrepräsentiert sind. Hinsichtlich der Beschäftigtenzahlen und Umsätze handelt es sich in der Befragung überwiegend um kleine und mittelständische Betriebe, wiewohl auch einige größere Unternehmen berücksichtigt wurden.
Inhalt: Umweltbeziehungen und Verantwortungsbewußtsein von Unternehmen -Ökologische Anliegen der Unternehmensumwelt -Verantwortliches Verhalten von Unternehmen -Der Risiko- und Krisenbegriff Subjektive Wahrnehmung und Bewertung von Risiken und Krisen -Subjektive Risikowahrnehmung: Wahrnehmung quantitativer Risikofaktoren,die Wahrnehmung qualitativer Merkmale der Risikoquelle, individuelle Risikodeterminanten -Empirische Studie zur Risikowahrnehmung -Subjektive Krisenbewältigung: Prozesse der Krisenentstehung und –entwicklung, Merkmale der Krisenwahrnehmung durch Manager, Verhaltenswissenschaftliche Theorien zur Krisenbewältigung Risiko- und Krisenmanagement
Public pensions in the U.S.
(2005)
Contents: The Public Old Age Insurance of the U.S. -Historical overview -Technical details -Individual equity and social adequacy The Economic Problem of Old Age -Risks and economic security -Old age, retirement, and idividual precaution -Insurance markets, market failures, and social insurance -Options for public pension systems The Problems of Social Security -The financial balance of OASDI -Causes of the long-run problems -Rates of return -Conclusion - The case for Social Security reform Proposed Remedies -Full, partial, or no privatization? -The President's Commission to Strengthen Social Security -Kotlikoff's Personal Security System -The Diamond-Orszag Three-Part plan
Many European countries have experienced a significant increase of unemployment in recent years. This paper reviews several theoretical models that try to explain this phenomenon. Predominantly, these models claim a link between the poor performance of European labor markets and the high level of market regulation. Commonly referred to as the Eurosclerosis debate, prominent approaches consider insider-outsider relationships, search-models, and the influence of hiring and firing costs on equilibrium employment. The paper presents empirical evidence of each model and studies the relevance of the identified rigidities as a determinant of high unemployment in Europe. Furthermore, a case study analyzes the unemployment problem in Germany and critically discusses new reform efforts. In particular this section analyzes whether the recently enacted Hartz reforms can induce higher employment.
Revisiting public investment
(2004)
The consumption equivalence method is the theoretical basis of public cost-benefit analysis. Consumption equivalence public capital prices are explicitly introduces in order to sufficiently care for the opportunity cost of public expenditure. This can solve the dispute about the social rate of discount within public cost-benefit analysis witch was generated on a criterion looking similar to the capital value formula, known as Lind’s approach. The social rate of discount is liberated from opportunity costs considerations and the discounting away of the effects for future welfare vanishes. The corresponding question whether one should accept a positive value of the pure rate of social time preference is an old issue. Its current state between the prescriptive and descriptive view can also be interpreted as a consequence of the oversimplification of standard cost– benefit analysis. But apart from an economic self-process the pure rate of social time preference is also defined as a business-as-usual value of social distance discounting. Hence, a political choice has to be made about this rate which is free in principal.
An exhaustive and disjoint decomposition of social choice situations is derived in a general set theoretical framework using the new tools of the Lifted Pareto relation on the power set of social states representing a pre-choice comparison of choice option sets. The main result is the classification of social choice situations which include three types of social choice problems. First, we usually observe the common incompleteness of the Pareto relation. Second, a kind of non-compactness problem of a choice set of social states can be generated. Finally, both can be combined. The first problem root can be regarded as natural everyday dilemma of social choice theory whereas the second may probably be much more due to modeling technique implications. The distinction is enabled at a very general set theoretical level. Hence, the derived classification of social choice situations is applicable on almost every relevant economic model.
Inhalt: Dynamische Interpretation der Leistungsfähigkeit Integrierte Einkommens- und Gewinnbesteuerung Zins- und Sparbereinigung Individuelle Fairness und Familiengerechtigkeit Einfachheit für Administration und Bürger Auswirkungen auf Steueraufkommen und Einkommensverteilung Generationengerechtigkeit Begleitende Maßnahmen Systemdynamik und Wirtschaftswachstum
Inhalt: Finanz- und belastungspolitische Konsequenzen -Die Methode -Die Ergebnisse -Die Reformnotwendigkeit Zur gegenwärtigen Lage der Rentnerhaushalte -Das Vier-Säulen-System der Alterssicherung -Die Einkommenssituation der Rentnerhaushalte -Die praktizierte Rentenbesteuerung Einfachheit, Transparenz und Akzeptanz Grundsicherung, Alterssicherung und Rentenbesteuerung -Grundsicherung und Alterssicherung -Gesetzliche und freiwillige Alterssicherung -Korrespondenzprinzip und Rentenbesteuerung
Face-to-face communication is multimodal. In unscripted spoken discourse we can observe the interaction of several "semiotic layers", modalities of information such as syntax, discourse structure, gesture, and intonation. We explore the role of gesture and intonation in structuring and aligning information in spoken discourse through a study of the co-occurrence of pitch accents and gestural apices. Metaphorical spatialization through gesture also plays a role in conveying the contextual relationships between the speaker, the government and other external forces in a naturally-occurring political speech setting.
Diskurspragmatische Faktoren für Topikalität und Verbstellung in der ahd. Tatianübersetzung (9. Jh.)
(2005)
The paper presents work in progress on the interaction between information structure and word order in Old High German based on data from the Tatian translation (9th century). The examination of the position of the finite verb in correspondence with the pragmatic status of discourse referents reveals an overall tendency for verb-initial order in thetic/all-focus sentences, whereas in categorical/topic-comment sentences verb-second placement with an initial topic constituent is preferred. This conclusion provides support for the hypothesis stated in Donhauser & Hinterhölzl (2003) that the finite verb form in Early Germanic serves to distinguish the information-structural domains of Topic and Focus. Finally, the investigation sheds light on the process of language change that led to the overall spread of verb-second in main clauses of modern German.
This paper investigates the structural properties of morphosyntactically marked focus constructions, focussing on the often neglected non-focal sentence part in African tone languages. Based on new empirical evidence from five Gur and Kwa languages, we claim that these focus expressions have to be analysed as biclausal constructions even though they do not represent clefts containing restrictive relative clauses. First, we relativize the partly overgeneralized assumptions about structural correspondences between the out-of-focus part and relative clauses, and second, we show that our data do in fact support the hypothesis of a clause coordinating pattern as present in clause sequences in narration. It is argued that we deal with a non-accidental, systematic feature and that grammaticalization may conceal such basic narrative structures.
The Semantics of Ellipsis
(2005)
There are four phenomena that are particularly troublesome for theories of ellipsis: the existence of sloppy readings when the relevant pronouns cannot possibly be bound; an ellipsis being resolved in such a way that an ellipsis site in the antecedent is not understood in the way it was there; an ellipsis site drawing material from two or more separate antecedents; and ellipsis with no linguistic antecedent. These cases are accounted for by means of a new theory that involves copying syntactically incomplete antecedent material and an analysis of silent VPs and NPs that makes them into higher order definite descriptions that can be bound into.
We present a system for the linguistic exploration and analysis of lexical cohesion in English texts. Using an electronic thesaurus-like resource, Princeton WordNet, and the Brown Corpus of English, we have implemented a process of annotating text with lexical chains and a graphical user interface for inspection of the annotated text. We describe the system and report on some sample linguistic analyses carried out using the combined thesaurus-corpus resource.
Fronting of an infinite VP across a finite main verb-akin to German "VP-topicalization"-can be found also in Czech and Polish. The paper discusses evidence from large corpora for this process and some of its properties, both syntactic and information-structural. Based on this case, criteria for more user-friedly searching and retrieval of corpus data in syntactic research are being developed.
Multiple hierarchies
(2005)
In this paper, we present the Multiple Annotation approach, which solves two problems: the problem of annotating overlapping structures, and the problem that occurs when documents should be annotated according to different, possibly heterogeneous tag sets. This approach has many advantages: it is based on XML, the modeling of alternative annotations is possible, each level can be viewed separately, and new levels can be added at any time. The files can be regarded as an interrelated unit, with the text serving as the implicit link. Two representations of the information contained in the multiple files (one in Prolog and one in XML) are described. These representations serve as a base for several applications.
This paper describes the standardization problems that come up in a diachronic corpus: it has to cope with differing standards with regard to diplomaticity, annotation, and header information. Such highly het-erogeneous texts must be standardized to allow for comparative re-search without (too much) loss of information.
This paper presents some concepts and principles used in the development of a database of multilingual spoken discourse at the University of Hamburg. The emphasis of the first part is on general considerations for the handling of heterogeneous data sets: After showing that diversity in transcription data is partly conceptually and partly technologically motivated, it is argued that the processing of transcription corpora should be approached via a three-level architecture which separates form (application) and content (data) on the one hand, and logical and physical data structures on the other hand. Such an architecture does not only pave the way for modern text-technological approaches to linguistic data processing, it can also help to decide where and how a standardization in the work with heterogeneous data is possible and desirable and where it would run counter to the needs of the research community. It is further argued that, in order to ensure user acceptance, new solutions developed in this approach must take care not to abandon established concepts too quickly. The focus of the second part is on some practical experiences with users and technologies gained in the four years’ project work. Concerning the practical development work, the value of open standards like XML and Unicode is emphasized and some limitations of the “platform-independent” JAVA technology are indicated. With respect to users of the EXMARaLDA system, a predominantly conservative attitude towards technological innovations in transcription corpus work can be stated: individual users tend to stick to known functionalities and are reluctant to adopt themselves to the new possibilities. Furthermore, an active commitment to cooperative corpus work still seems to be the exception rather than the rule. It is concluded that technological innovations can contribute their share to a progress in the work with heterogeneous linguistic data, but that they will have to be supplemented, in the long run, with an adequate methodological reflection and the creation of an appropriate infrastructure.
Unity in diversity
(2005)
This paper describes the creation and preparation of TUSNELDA, a collection of corpus data built for linguistic research. This collection contains a number of linguistically annotated corpora which differ in various aspects such as language, text sorts / data types, encoded annotation levels, and linguistic theories underlying the annotation. The paper focuses on this variation on the one hand and the way how these heterogeneous data are integrated into one resource on the other hand.
The concepts of food deficit, hunger, undernourishment and food security are discussed. Axioms and indices for the assessment of nutrition of individuals and groups are suggested. Furthermore a measure for food aid donor performance is developed and applied to a sample of bilateral and multilateral donors providing food aid for African countries.
Die zunehmende Erosion der veranlagten Einkommensteuer wirft die Frage auf, inwieweit die Möglichkeit der Verechnung positiver mit negativen Einkünften dafür verantwortlich ist. Auf der Basis eines Mikrosimulationsmodells analysiert der Beitrag die Wirkungen dieser im deutschen Einkommensteuerrecht möglichen Verrechenbarkeit. Zum einen werden die aus der Abschaffung der Verrechnungsmöglichkeiten resultierenden Wanderungen von Steuerpflichtigen in höhere Einkommensklassen und zum anderen die Auswirkungen auf das Steueraufkommen untersucht. Insgesamt vermindern ca. 5 % der Steuerpflichtigen ihre positiven Einkünfte durch negative Einkünfte einer anderen Einkunftsart. Im Hinblick auf das Steueraufkommen zeichnen sich beträchtliche Steuerausfälle in Höhe von ca. 33 Mrd. DM durch diese Verrechnungsmöglichkeit ab.
Inhalt: Theoretische Begründung einer Besteuerung von Alterseinkünften Kritische Überprüfung einiger Argumente Die Reformvorschläge und das Simulationsmodell Die Simulationsergebnisse Kritische Bewertung der Ergebnisse Mit einem Kommentar von Hans-Peter Weikard: Rentenbesteuerung und Korrespondenzprinzip: 1. Wie selbstverständlich ist das Korrespondenzprinzip? 2. Die zeitliche Dimension des Korrespondenzprinzips 3. Eine unzulässige Interpretation 4. Fazit
ANNIS
(2004)
In this paper, we discuss the design and implementation of our first version of the database "ANNIS" ("ANNotation of Information Structure"). For research based on empirical data, ANNIS provides a uniform environment for storing this data together with its linguistic annotations. A central database promotes standardized annotation, which facilitates interpretation and comparison of the data. ANNIS is used through a standard web browser and offers tier-based visualization of data and annotations, as well as search facilities that allow for cross-level and cross-sentential queries. The paper motivates the design of the system, characterizes its user interface, and provides an initial technical evaluation of ANNIS with respect to data size and query processing.
Focus strategies in chadic
(2004)
We argue that the standard focus theories reach their limits when confronted with the focus systems of the Chadic languages. The backbone of the standard focus theories consists of two assumptions, both called into question by the languages under consideration. Firstly, it is standardly assumed that focus is generally marked by stress. The Chadic languages, however, exhibit a variety of different devices for focus marking. Secondly, it is assumed that focus is always marked. In Tangale, at least, focus is not marked consistently on all types of constituents. The paper offers two possible solutions to this dilemma.
We argue that there is a crucial difference between determiner and adverbial quantification. Following Herburger [2000] and von Fintel [1994], we assume that determiner quantifiers quantify over individuals and adverbial quantifiers over eventualities. While it is usually assumed that the semantics of sentences with determiner quantifiers and those with adverbial quantifiers basically come out the same, we will show by way of new data that quantification over events is more restricted than quantification over individuals. This is because eventualities in contrast to individuals have to be located in time which is done using contextual information according to a pragmatic resolution strategy. If the contextual information and the tense information given in the respective sentence contradict each other, the sentence is uninterpretable. We conclude that this is the reason why in these cases adverbial quantification, i.e. quantification over eventualities, is impossible whereas quantification over individuals is fine.
The papers in this volume were presented at the workshop Heterogeneity in Linguistic Databases', which took place on July 9, 2004 at the University of Potsdam. The workshop was organized by project D1: Linguistic Database for Information Structure: Annotation and Retrieval', a member project of the SFB 632, a collaborative research center entitled Information Structure: the Linguistic Means for Structuring Utterances, Sentences and Texts'. The workshop brought together both developers and users of linguistic databases from a number of research projects which work on an empirical basis, all of which have to cope with different sorts of heterogeneity: primary linguistic data and annotated information may be heterogeneous, as well as the data structures representing them. The first four papers (by Wagner, Schmidt, Lüdeling, and Witt) address aspects of heterogeneous data from the point of view of database developers; the remaining three papers (by Meyer, Smith, and Teich/Fankhauser) focus on data exploitation by the users.
Interdisciplinary studies on information structure : ISIS ; working papers of the SFB 632. - Vol. 1
(2004)
Contents: A1: Phonology and syntax of focussing and topicalisation: Gisbert Fanselow: Cyclic Phonology–Syntax-Interaction: Movement to First Position in German Caroline Féry and Laura Herbst: German Sentence Accent Revisited Shinichiro Ishihara: Prosody by Phase: Evidence from Focus Intonation–Wh-scope Correspondence in Japanese A2: Quantification and information structure: Cornelia Endriss and Stefan Hinterwimmer: The Influence of Tense in Adverbial Quantification A3: Rhetorical Structure in Spoken Language: Modeling of Global Prosodic Parameters: Ekaterina Jasinskaja, Jörg Mayer and David Schlangen: Discourse Structure and Information Structure: Interfaces and Prosodic Realization B2: Focussing in African Tchadic languages: Katharina Hartmann and Malte Zimmermann: Focus Strategies in Chadic: The Case of Tangale Revisited D1: Linguistic database for information structure: Annotation and retrieval: Stefanie Dipper, Michael Götze, Manfred Stede and Tillmann Wegst: ANNIS: A Linguistic Database for Exploring Information Structure
German foreign policy is in the midst of a far-reaching transformation. Contrary to disciplinary expectations, this process is neither properly captured by descriptions in the liberal tradition („Europeanisation“, „Civilian Power“) nor by Realist expectations that Germany is doomed to „remilitarise“ and/or „renationalise“. However, the key term of foreign policy discourse, „normalisation“, is an unmistakable code, signalling a rediscovery of traditional Realpolitik practices which fit Germany’s current environment. The paper argues that rather than merely playing the role of an obedient disciple of Realpolitik socialisers, Germany ought to rehabilitate the foreign policy tradition of the Bonn Republic in support of an active Idealpolitik transformation of its environment. The article serves as a starting point for a debate on German foreign policy in the upcoming issues of WeltTrends.
This article investigates the fictional narratives written by „Sub-commandante Marcos“ of the Zapatista movement EZLN. It is shown that Marcos uses three distinct frames of reference in his fictional account of the Zapatista guerrilla: an ethnic, a national and a post-national one. Contrary to other studies that emphasize the harmony between the three levels, it can be argued that there exists a fundamental tension between them. There is a tension between the ethnic discourse and the Mexican nationalist discourse which envisions a nation rather than a nation dominated by a single ethno-cultural group. Finally, it can be deduced from these tensions that the EZLN guerrilla is subject to divergent pressures.
Hegemonialmächte im Vorderen und Mittleren Orient : die Dritte Partei in internationalen Konflikten
(1997)
During the last five decades hegemons played an important role in de-escalating international conflicts in the subregion defined as the core of Oriens Islamicus. Statistical analysis of large datasets shows that half of all conflicts remained without any interference from the hegemonial powers at all - both on global scale and in the subregion. In all other cases however, hegemons (especially super-powers in the role of patrons) tended more often to act as (power-) mediators when their client-state was engaged in conflict with a client of the opposing superpower in Oriens Islamicus than they did on global scale. They did this in their own interest in order to avoid direct involvement, i.e. possible danger of a nuclear escalation. In contrast to conventional mediation theory they were more effective in conflict de-escalation than other mediators, especially in conflicts between Israel and its Arab neighbours. The end of bipolarity in the international system also brought this mechanism of de-escalation to an end. It leaves the hegemon(s) as a potentially powerful third party on the one hand, but on the other their inclination to become involved in regional conflict remains rather diminished as long as the basic national interests in the area are not at stake.
The layer-by-layer assembly (LBL) of polyelectrolytes has been extensively studied for the preparation of ultrathin films due to the versatility of the build-up process. The control of the permeability of these layers is particularly important as there are potential drug delivery applications. Multilayered polyelectrolyte microcapsules are also of great interest due to their possible use as microcontainers. This work will present two methods that can be used as employable drug delivery systems, both of which can encapsulate an active molecule and tune the release properties of the active species. Poly-(N-isopropyl acrylamide), (PNIPAM) is known to be a thermo-sensitive polymer that has a Lower Critical Solution Temperature (LCST) around 32oC; above this temperature PNIPAM is insoluble in water and collapses. It is also known that with the addition of salt, the LCST decreases. This work shows Differential Scanning Calorimetry (DSC) and Confocal Laser Scanning Microscopy (CLSM) evidence that the LCST of the PNIPAM can be tuned with salt type and concentration. Microcapsules were used to encapsulate this thermo-sensitive polymer, resulting in a reversible and tunable stimuli- responsive system. The encapsulation of the PNIPAM inside of the capsule was proven with Raman spectroscopy, DSC (bulk LCST measurements), AFM (thickness change), SEM (morphology change) and CLSM (in situ LCST measurement inside of the capsules). The exploitation of the capsules as a microcontainer is advantageous not only because of the protection the capsules give to the active molecules, but also because it facilitates easier transport. The second system investigated demonstrates the ability to reduce the permeability of polyelectrolyte multilayer films by the addition of charged wax particles. The incorporation of this hydrophobic coating leads to a reduced water sensitivity particularly after heating, which melts the wax, forming a barrier layer. This conclusion was proven with Neutron Reflectivity by showing the decreased presence of D2O in planar polyelectrolyte films after annealing creating a barrier layer. The permeability of capsules could also be decreased by the addition of a wax layer. This was proved by the increase in recovery time measured by Florescence Recovery After Photobleaching, (FRAP) measurements. In general two advanced methods, potentially suitable for drug delivery systems, have been proposed. In both cases, if biocompatible elements are used to fabricate the capsule wall, these systems provide a stable method of encapsulating active molecules. Stable encapsulation coupled with the ability to tune the wall thickness gives the ability to control the release profile of the molecule of interest.
Collisions of black holes and neutron stars, named mixed binaries in the following, are interesting because of at least two reasons. Firstly, it is expected that they emit a large amount of energy as gravitational waves, which could be measured by new detectors. The form of those waves is expected to carry information about the internal structure of such systems. Secondly, collisions of such objects are the prime suspects of short gamma ray bursts. The exact mechanism for the energy emission is unknown so far. In the past, Newtonian theory of gravitation and modifications to it were often used for numerical simulations of collisions of mixed binary systems. However, near to such objects, the gravitational forces are so strong, that the use of General Relativity is necessary for accurate predictions. There are a lot of problems in general relativistic simulations. However, systems of two neutron stars and systems of two black holes have been studies extensively in the past and a lot of those problems have been solved. One of the remaining problems so far has been the use of hydrodynamic on excision boundaries. Inside excision regions, no evolution is carried out. Such regions are often used inside black holes to circumvent instabilities of the numerical methods near the singularity. Methods to handle hydrodynamics at such boundaries have been described and tests are shown in this work. One important test and the first application of those methods has been the simulation of a collapsing neutron star to a black hole. The success of these simulations and in particular the performance of the excision methods was an important step towards simulations of mixed binaries. Initial data are necessary for every numerical simulation. However, the creation of such initial data for general relativistic situations is in general very complicated. In this work it is shown how to obtain initial data for mixed binary systems using an already existing method for initial data of two black holes. These initial data have been used for evolutions of such systems and problems encountered are discussed in this work. One of the problems are instabilities due to different methods, which could be solved by dissipation of appropriate strength. Another problem is the expected drift of the black hole towards the neutron star. It is shown, that this can be solved by using special gauge conditions, which prevent the black hole from moving on the computational grid. The methods and simulations shown in this work are only the starting step for a much more detailed study of mixed binary system. Better methods, models and simulations with higher resolution and even better gauge conditions will be focus of future work. It is expected that such detailed studies can give information about the emitted gravitational waves, which is important in view of the newly built gravitational wave detectors. In addition, these simulations could give insight into the processes responsible for short gamma ray bursts.
Nikotin in den unterschiedlichsten Darreichungsformen verringert bei verschiedenen Spezies im räumlichen Hinweisreizparadigma die Kosten invalider Hinweisreize. Welcher Teilprozess genau durch Nikotin beeinflusst wird, ist bislang nicht untersucht worden. Die gängige Interpretation ist, daß Nikotin das Loslösen von Aufmerksamkeit von einem bisher beachteten Ort erleichtert. In fünf Studien, drei elektrophysiologischen und zwei behavioralen wurden drei mögliche Mechanismen der Nikotinwirkung an Nichtrauchern untersucht. Experiment 1 und 2 gingen der Frage nach, ob Nikotin eine Modulation sensorischer gain Kontrolle bewirkt. Dazu wurden ereigniskorrelierte Potentiale (EKP) im Posner-Paradigma erhoben und die Wirkung von Nikotin auf die aufmerksamkeitsassoziierten Komponenten P1 und N1 betrachtet. Nikotin verringerte die Kosten invalider Hinweisreize bei Aufmerksamkeitslenkung durch endogene Hinweisreize, nicht aber bei exogenen Hinweisreizen. Die P1 und N1 Komponenten zeigten sich unbeeinflusst von Nikotin, damit findet also die Annahme einer Wirkung auf sensorische Suppression keine Unterstützung. In Experiment 3 und 4 wurde untersucht, ob Nikotin einen Effekt auf kostenträchtige unwillkürliche Aufmerksamkeitsverschiebungen, Distraktionen, hat. In Experiment 3 wurden in einem räumlichen Daueraufmerksamkeitsparadigma Distraktionen durch deviante Stimulusmerkmale ausgelöst und die Wirkung von Nikotin auf eine distraktionsassoziierte Komponente des EKP, die P3a, betrachtet. In Experiment 4 wurde in einem Hinweisreizparadigma durch zusätzliche Stimuli eine Distraktion ausgelöst und die Nikotinwirkung auf die Reaktionszeitkosten untersucht. Nikotin zeigte keinen Einfluss auf Distraktionskosten in beiden Studien und auch keine Wirkung auf die P3a Komponente in Experiment 3. In Experiment 4 wurde zusätzlich die Wirkung von Nikotin auf das Loslösen von Aufmerksamkeit untersucht, indem die Schwierigkeit des Loslösens variiert wurde. Auch hier zeigte sich keine Nikotinwirkung. Allerdings konnte in beiden Studien weder die häufig berichtete generelle Reaktionszeitverkürzung noch die Verringerung der Kosten invalider Hinweisreize repliziert werden, so dass zum Einen keine Aussage über die Wirkung von Nikotin auf Distraktionen oder den Aufmerksamkeitsloslöseprozess gemacht werden können, zum Anderen sich die Frage stellte, unter welchen Bedingungen Nikotin einen differentiellen Effekt überhaupt zeigt. Im letzten Experiment wurde hierzu die Häufigkeit der Reaktionsanforderung einerseits und die zeitlichen Aspekte der Aufmerksamkeitslenkung andererseits variiert und der Effekt des Nikotins auf den Validitätseffekt, die Reaktionszeitdifferenz zwischen valide und invalide vorhergesagten Zielreizen, betrachtet. Nikotin verringerte bei Individuen, bei denen Aufmerksamkeitslenkung in allen Bedingungen evident war, in der Tendenz den Validitätseffekt in der ereignisärmsten Bedingung, wenn nur selten willentliche Aufmerksamkeitsausrichtung notwendig war. Dies könnte als Hinweis gedeutet werden, dass Nikotin unter Bedingungen, die große Anforderungen an die Vigilanz stellen, die top-down Zuweisung von Aufmerksamkeitsressourcen unterstützt.
The advent of large-scale and high-throughput technologies has recently caused a shift in focus in contemporary biology from decades of reductionism towards a more systemic view. Alongside the availability of genome sequences the exploration of organisms utilizing such approach should give rise to a more comprehensive understanding of complex systems. Domestication and intensive breeding of crop plants has led to a parallel narrowing of their genetic basis. The potential to improve crops by conventional breeding using elite cultivars is therefore rather limited and molecular technologies, such as marker assisted selection (MAS) are currently being exploited to re-introduce allelic variance from wild species. Molecular breeding strategies have mostly focused on the introduction of yield or resistance related traits to date. However given that medical research has highlighted the importance of crop compositional quality in the human diet this research field is rapidly becoming more important. Chemical composition of biological tissues can be efficiently assessed by metabolite profiling techniques, which allow the multivariate detection of metabolites of a given biological sample. Here, a GC/MS metabolite profiling approach has been applied to investigate natural variation of tomatoes with respect to the chemical composition of their fruits. The establishment of a mass spectral and retention index (MSRI) library was a prerequisite for this work in order to establish a framework for the identification of metabolites from a complex mixture. As mass spectral and retention index information is highly important for the metabolomics community this library was made publicly available. Metabolite profiling of tomato wild species revealed large differences in the chemical composition, especially of amino and organic acids, as well as on the sugar composition and secondary metabolites. Intriguingly, the analysis of a set of S. pennellii introgression lines (IL) identified 889 quantitative trait loci of compositional quality and 326 yield-associated traits. These traits are characterized by increases/decreases not only of single metabolites but also of entire metabolic pathways, thus highlighting the potential of this approach in uncovering novel aspects of metabolic regulation. Finally the biosynthetic pathway of the phenylalanine-derived fruit volatiles phenylethanol and phenylacetaldehyde was elucidated via a combination of metabolic profiling of natural variation, stable isotope tracer experiments and reverse genetic experimentation.
In semi-arid savannas, unsustainable land use can lead to degradation of entire landscapes, e.g. in the form of shrub encroachment. This leads to habitat loss and is assumed to reduce species diversity. In BIOTA phase 1, we investigated the effects of land use on population dynamics on farm scale. In phase 2 we scale up to consider the whole regional landscape consisting of a diverse mosaic of farms with different historic and present land use intensities. This mosaic creates a heterogeneous, dynamic pattern of structural diversity at a large spatial scale. Understanding how the region-wide dynamic land use pattern affects the abundance of animal and plant species requires the integration of processes on large as well as on small spatial scales. In our multidisciplinary approach, we integrate information from remote sensing, genetic and ecological field studies as well as small scale process models in a dynamic region-wide simulation tool. <hr> Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung Workshop vom 9. - 10. Februar 2006.
Decisions for the conservation of biodiversity and sustainable management of natural resources are typically related to large scales, i.e. the landscape level. However, understanding and predicting the effects of land use and climate change on scales relevant for decision-making requires to include both, large scale vegetation dynamics and small scale processes, such as soil-plant interactions. Integrating the results of multiple BIOTA subprojects enabled us to include necessary data of soil science, botany, socio-economics and remote sensing into a high resolution, process-based and spatially-explicit model. Using an example from a sustainably-used research farm and a communally used and degraded farming area in semiarid southern Namibia we show the power of simulation models as a tool to integrate processes across disciplines and scales.
Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung Workshop vom 9. - 10. Februar 2006
Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung Workshop vom 9. - 10. Februar 2006
Mit der politischen Wende in den Staaten des ehemaligen Ostblockes wurde für viele militärisch genutzte Flächen ein tiefgreifender Nutzungswandel eingeleitet. Truppenübungsplätze als stark gestörte Bestandteile unserer Kulturlandschaft weisen auf großen Flächen naturschutzfachlich wertvolle Habitatmosaike mit speziellen Lebensgemeinschaften auf. Der Nutzungswandel ist mit einer Veränderung der Vegetationsstrukturen (Sukzession) und weiteren landschaftsökologischen Prozessen verbunden. Der ehemalige Truppenübungsplatz Döberitz im Norden der Landeshauptstadt Potsdam kann auf eine lange militärische Nutzungsgeschichte verweisen (erste Manöver des Soldatenkönigs im Jahr 1713). Nach 1992 wurden das NSG Döberitzer Heide (3.415 ha) und das NSG Ferbitzer Bruch (1.155 ha) ausgewiesen. Als Schutzgebiete nach der Vogelschutzrichtlinie sind sie Bestandteile des kohärenten Schutzgebietssystems Natura 2000 der europäischen Gemeinschaft. Trotz des Schutzstatus und der militärischen Altlasten unterliegt das Gebiet als größte zusammenhängende Naturfläche im engeren Verflechtungsraum des Landes Brandenburg einem hohen Nutzungsdruck. <hr> Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung Workshop vom 9. - 10. Februar 2006
In ihrem Bemühen, landwirtschaftliche Flächen standortgerecht zu bewirtschaften, sammelt eine zunehmende Anzahl landwirtschaftlicher Betriebe Informationen über die räumlich-zeitliche Verteilung von Boden- und Pflanzenmerkmalen auf ihren Schlägen. Diese Informationen dienen unmittelbar (Echtzeitansatz) oder mittelbar (Kartenansatz) zur Dosierung von Dünge- und Pflanzenschutzmitteln (Präzise Landbewirtschaftung). Zur Datensammlung werden vorrangig fahrzeuggestützte Sensoren und VIS- und NIR-Luftbilder, aufgenommen aus Sportflugzeugen, verwendet. Erste Betriebe erwerben von Dienstleistungsunternehmen aufbereitete Satelliten-Fernerkundungsdaten. Die landwirtschaftliche und agrartechnische Forschung ist bestrebt, die grundlegenden Muster (z.B. des Ertragspotentials) zu erkennen und damit den Aufwand der Betriebe für eine regelmäßige Informationserfassung gering zu halten. <hr> Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung Workshop vom 9. - 10. Februar 2006
Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung Workshop vom 9. - 10. Februar 2006
Fluvial systems are one of the major features shaping a landscape. They adjust to the prevailing tectonic and climatic setting and therefore are very sensitive markers of changes in these systems. If their response to tectonic and climatic forcing is quantified and if the climatic signal is excluded, it is possible to derive a local deformation history. Here, we investigate fluvial terraces and erosional surfaces in the southern Chilean forearc to assess a long-term geomorphic and hence tectonic evolution. Remote sensing and field studies of the Nahuelbuta Range show that the long-term deformation of the Chilean forearc is manifested by breaks in topography, sequences of differentially uplifted marine, alluvial and strath terraces as well as tectonically modified river courses and drainage basins. We used SRTM-90-data as basic elevation information for extracting and delineating drainage networks. We calculated hypsometric curves as an indicator for basin uplift, stream-length gradient indices to identify stream segments with anomalous slopes, and longitudinal river profiles as well as DS-plots to identify knickpoints and other anomalies. In addition, we investigated topography with elevation-slope graphs, profiles, and DEMs to reveal erosional surfaces. During the first field trip we already measured palaeoflow directions, performed pebble counting and sampled the fluvial terraces in order to apply cosmogenic nuclide dating (<sup>10Be, <sup>26Al) as well as provenance analyses. Our preliminary analysis of the Coastal Cordillera indicates a clear segmentation between the northern and southern parts of the Nahuelbuta Range. The Lanalhue Fault, a NW-SE striking fault zone oblique to the plate boundary, defines the segment boundary. Furthermore, we find a complex drainage re-organisation including a drainage reversal and wind gap on the divide between the Tirúa and Pellahuén basins east of the town Tirúa. The coastal basins lost most of their Andean sediment supply areas that existed in Tertiary and in part during early Pleistocene time. Between the Bío-Bío and Imperial rivers no Andean river is recently capable to traverse the Coastal Cordillera, suggesting ongoing Quaternary uplift of the entire range. From the spatial distribution of geomorphic surfaces in this region two uplift signals may be derived: (1) a long-term differential uplift process, active since the Miocene and possibly caused by underplating of subducted trench sediments, (2) a younger, local uplift affecting only the northern part of the Nahuelbuta Range that may be caused by the interaction of the forearc with the subduction of the Mocha Fracture Zone at the latitude of the Arauco peninsula. Our approach thus provides results in our attempt to decipher the characteristics of forearc development of active convergent margins using long-term geomorphic indicators. Furthermore, it is expected that our ongoing assessment will constrain repeatedly active zones of deformation. <hr> Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung Workshop vom 9. - 10. Februar 2006
The rigorous development, application and validation of distributed hydrological models obligates to evaluate data in a spatially distributed way. In particular, spatial model predictions such as the distribution of soil moisture, runoff generating areas or nutrient-contributing areas or erosion rates, are to be assessed against spatially distributed observations. Also model inputs, such as the distribution of modelling units derived by GIS and remote sensing analyses, should be evaluated against groundbased observations of landscape characteristics. So far, however, quantitative methods of spatial field comparison have rarely been used in hydrology. In this paper, we present algorithms that allow to compare observed and simulated spatial hydrological data. The methods can be applied for binary and categorical data on regular grids. They comprise cell-by-cell algorithms, cell-neighbourhood approaches that account for fuzziness of location, and multi-scale algorithms that evaluate the similarity of spatial fields with changing resolution. All methods provide a quantitative measure of the similarity of two maps. The comparison methods are applied in two mountainous catchments in southern Germany (Brugga, 40 km<sup>2) and Austria (Löhnersbach, 16 km<sup>2). As an example of binary hydrological data, the distribution of saturated areas is analyzed in both catchments. For categorical data, vegetation zones that are associated with different runoff generation mechanisms are analyzed in the Löhnersbach. Mapped spatial patterns are compared to simulated patterns from terrain index calculations and from satellite image analysis. It is discussed how particular features of visual similarity between the spatial fields are captured by the quantitative measures, leading to recommendations on suitable algorithms in the context of evaluating distributed hydrological models.
Moderne Softwaresysteme sind komplexe Gebilde, welche häufig im Verbund mit anderen technischen und betriebswirtschaftlichen Systemen eingesetzt werden. Für die Hersteller solcher Systeme stellt es oft eine große Herausforderung dar, den oft weit reichenden Anforderungen bezüglich der Anpassbarkeit solcher Systeme gerecht zu werden. Zur Erfüllung dieser Anforderungen hat es sich vielfach bewährt, eine virtuelle Maschine in das betreffende System zu integrieren. Die Dissertation richtet sich insbesondere an Personen, die vor der Aufgabe der Integration virtueller Maschinen in bestehende Systeme stehen und zielt darauf ab, solche für die Entscheidung über Integrationsfragen wichtigen Zusammenhänge klar darzustellen. Typischerweise treten bei der Integration einer virtuellen Maschine in ein System eine Reihe unterschiedlicher Problemstellungen auf. Da diese Problemstellungen oft eng miteinander verzahnt sind, ist eine isolierte Betrachtung meist nicht sinnvoll. Daher werden die Problemstellungen anhand eines zentral gewählten, sehr umfangreichen Beispiels aus der industriellen Praxis eingeführt. Dieses Beispiel hat die Integration der "Java Virtual Machine" in den SAP R/3 Application Server zum Gegenstand. Im Anschluss an dieses Praxisbeispiel wird die Diskussion der Integrationsproblematik unter Bezug auf eine Auswahl weiterer, in der Literatur beschriebener Integrationsbeispiele vertieft. Das Hauptproblem bei der Behandlung der Integrationsproblematik bestand darin, dass die vorgefundenen Beschreibungen, der als Beispiel herangezogenen Systeme, nur bedingt als Basis für die Auseinandersetzung mit der Integrationsproblematik geeignet waren. Zur Schaffung einer verwertbaren Diskussionsgrundlage war es daher erforderlich, eine homogene, durchgängige Modellierung dieser Systeme vorzunehmen. Die Modellierung der Systeme erfolgte dabei unter Verwendung der "Fundamental Modeling Concepts (FMC)". Die erstellten Modelle sowie die auf Basis dieser Modelle durchgeführte Gegenüberstellung der unterschiedlichen Ansätze zur LÖsung typischer Integrationsprobleme bilden den Hauptbeitrag der Dissertation. Im Zusammenhang mit der Integration virtueller Maschinen in bestehende Systeme besteht häufig der Bedarf, zeitgleich mehrere "Programme" durch die integrierte virtuelle Maschine ausführen zu lassen. Angesichts der Konstruktionsmerkmale vieler heute verbreiteter virtueller Maschinen stellt die Realisierung eines "betriebsmittelschonenden Mehrprogrammbetriebs" eine große Herausforderung dar. Die Darstellung des Spektrums an Maßnahmen zur Realisierung eines "betriebsmittelschonenden Mehrprogrammbetriebs" bildet einen zweiten wesentlichen Beitrag der Dissertation.