Tethys-Foraminiferen im Münsterländer Kreide-Becken

Aus dem Obercampan von Münster und Umgebung werden neben 5 biostratigraphisch leitenden Foraminiferen noch 9 Arten beschrieben und abgebildet, die bisher in N-Deutschland nur aus der höchsten Oberkreide und dem Dan publiziert worden sind. Viele der letztgenannten Foraminiferen sind in den Ablagerungen der Tethys häufig, sogar in der Oberkreide unterhalb des Maastricht

Exchange Rate Dynamics and the Overshooting Hypothesis

In this paper we analyze the determinants of the evolution of ex- change rates within the context of alternative models of exchange rate dynamics. We examine the overshooting hypothesis in models which emphasize differential speeds of adjustment in asset and goods markets as well as in models which emphasize portfolio balance considerations. We show that exchange rate overshooting is not an intrinsic characteristic of the foreign exchange market and that it depends on a set of specific assumptions. We also show that the overshooting is not a characteristic of the assumption of perfect foresight nor does it depend in general on the assumption that goods and asset markets clear at different speeds. As long as the speeds of adjustment in the various markets are less than infinite, the key factor determining the short run effects of a monetary expansion is the degree of capital mobility. When capital is highly mobile, the exchange rate overshoots its long-run value and when capital is relatively immobile the exchange rate undershoots its long-run value. Within the context of the portfolio-balance model we show that the effects of a monetary expansion on the dynamics of exchange rates and in particular on whether exchange rates overshoot or undershoot their equilibrium path depend critically on the specification of asset choice, on the degree of substitution among assets, and on the quality of the various assets in being an inflation hedge, Specifically, when internationally traded goods are a better inflation hedge than nontraded goods, the nominal exchange rate overshoots the domestic price level and conversely.

Characterization of dynamical regimes and entanglement sudden death in a microcavity quantum - dot system

The relation between the dynamical regimes (weak and strong coupling) and entanglement for a dissipative quantum - dot microcavity system is studied. In the framework of a phenomenological temperature model an analysis in both, temporal (population dynamics) and frequency domain (photoluminescence) is carried out in order to identify the associated dynamical behavior. The Wigner function and concurrence are employed to quantify the entanglement in each regime. We find that sudden death of entanglement is a typical characteristic of the strong coupling regime.Comment: To appear in Journal of Physics: Condensed Matte

Using RDF to Model the Structure and Process of Systems

Many systems can be described in terms of networks of discrete elements and their various relationships to one another. A semantic network, or multi-relational network, is a directed labeled graph consisting of a heterogeneous set of entities connected by a heterogeneous set of relationships. Semantic networks serve as a promising general-purpose modeling substrate for complex systems. Various standardized formats and tools are now available to support practical, large-scale semantic network models. First, the Resource Description Framework (RDF) offers a standardized semantic network data model that can be further formalized by ontology modeling languages such as RDF Schema (RDFS) and the Web Ontology Language (OWL). Second, the recent introduction of highly performant triple-stores (i.e. semantic network databases) allows semantic network models on the order of $10^9$ edges to be efficiently stored and manipulated. RDF and its related technologies are currently used extensively in the domains of computer science, digital library science, and the biological sciences. This article will provide an introduction to RDF/RDFS/OWL and an examination of its suitability to model discrete element complex systems.Comment: International Conference on Complex Systems, Boston MA, October 200

Light capsules shaped by curvilinear meta-surfaces

We propose a simple yet efficient method for generating in-plane hollow beams with a nearly-full circular light shell without the contribution of backward propagating waves. The method relies on modulating the phase in the near field of a centro-symmetric optical wavefront, such as that from a high-numericalaperture focused wave field. We illustrate how beam acceleration may be carried out by using an ultranarrow non-flat meta-surface formed by engineered plasmonic nanoslits. A mirrorsymmetric, with respect to the optical axis, circular caustic surface is numerically demonstrated that can be used as an optical bottle

Characterization of slow and fast phase nystagmus

A current literature review of the analog and digital process of vestibular and optical kinetic nystagmus reveals little agreement in the methods used by various labs. The strategies for detection of saccade (fast phase velocity component of nystagmus) vary between labs, and most of the process have not been evaluated and validated with a standard database. A survey was made of major vestibular labs in the U.S. that perform computer analyses of vestibular and optokinetic reflexes to stimuli, and a baseline was established from which to standardize data acquisition and analysis programs. The concept of an Error Index was employed as the criterium for evaluating the performance of the vestibular analysis software programs. The performance criterium is based on the detection of saccades and is the average of the percentages of missed detections and false detections. Evaluation of the programs produced results for lateral gaze with saccadic amplitude of one, two, three, five, and ten degrees with various signal-to-noise ratios. In addition, results were obtained for sinusoidal pursuit of 0.05, 0.10, and 0.50 Hz with saccades from one to ten degrees at various signal-to-noise ratios. Selection of the best program was made from the performance in the lateral gaze with three degrees of saccadic amplitude and in the 0.10 Hz sinusoid with three degrees of saccadic amplitude

Welfare-Theoretical Analyses of the Brain Drain

The paper reviews and synthesises the theoretical analyses of the brain drain in the earlier literature and in the present symposium in the Journal on the subject. Static analysis and dynamic analysis are distinguished, critical issues are raised relating to how welfare changes should be discussed in the context of migration, and possibilities of fruitful future research are outlined

Comparison of dynamic isotope power systems for distributed planet surface applications

Dynamic isotope power system (DIPS) alternatives were investigated and characterized for the surface mission elements associated with a lunar base and subsequent manned Mars expedition. System designs based on two convertor types were studied. These systems were characterized parametrically and compared over the steady-state electrical output power range 0.2 to 20 kWe. Three methods of thermally integrating the heat source and the Stirling heater head were considered, depending on unit size. Figures of merit were derived from the characterizations and compared over the parametric range. Design impacts of mission environmental factors are discussed and quantitatively assessed