Price Control and Other Regulatory Issues

Germany’s complete overhaul of the telecommunications legislation seeks to ensure easy access to the German market and a level playing field for all, based on regulation that is independent and quick to intervene against any abuse of market power, in other words to ensure a sound and predictable investment climate. Our regulation aims to promote competition in the telecommunications sector and to encourage technological and organizational progress at the same time. This policy stands to benefit all: customers, Deutsche Telekom AG, new entrants, the workforce, Germany as a place to do business, and the prospects of the German economy generally. The World Trade Organization estimates that a quarter of all economic activity in the industrial countries will be accounted for in the future by electronic commerce. Germany is preparing itself for these global challenges and has already made a promising start

Irreducible pionic effects in nucleon-deuteron scattering below 20 MeV

The consequences of a recently introduced irreducible pionic effect in low energy nucleon-deuteron scattering are analyzed. Differential cross-sections, nucleon (vector) and deuteron (vector and tensor) analyzing powers, and four different polarization transfer coefficients have been considered. This 3NF-like effect is generated by the pion-exchange diagram in presence of a two-nucleon correlation and is partially cancelled by meson-retardation contributions. Indications are provided that such type of effects are capable to selectively increase the vector (nucleon and deuteron) analyzing powers, while in the considered energy range they are almost negligible on the differential cross sections. These indications, observed with different realistic nucleon-nucleon interactions, provide additional evidences that such 3NF-like effects have indeed the potential to solve the puzzle of the vector analyzing powers. Smaller but non negligible effects are observed for the other spin observables. In some cases, we find that the modifications introduced by such pionic effects on these spin observables (other than the vector analyzing powers) are significant and interesting and could be observed by experiments.Comment: 33 pages, 17 figures, 3 Tables, RevTe

Three-Body Scattering Below Breakup Threshold: An Approach without using Partial Waves

The Faddeev equation for three-body scattering below the three-body breakup threshold is directly solved without employing a partial wave decomposition. In the simplest form it is a three-dimensional integral equation in four variables. From its solution the scattering amplitude is obtained as function of vector Jacobi momenta. Based on Malfliet-Tjon type potentials differential and total cross sections are calculated. The numerical stability of the algorithm is demonstrated and the properties of the scattering amplitude discussed.Comment: 21 pages, 7 figures included, uses psfig, revised versio

A review of the ONR/NAVAIR research option combustion instabilities in compact ramjets, 1983-1988

This paper consists of two parts summarizing two portions of the ONR/NAVAIR Research Option. The option began in 1983 and continued for five years, involving 11 organizations. Simultaneously, similar or related programs supported by other agencies or institutions were being carried out in several other places. Results of those programs have been briefly summarized in five papers collected in a document to be published by C.P.L.A. This paper contains two of the five papers in that document. Here we cover the subjects of approximate analyses and stability; and large-scale structures and passive control. The first is concerned chiefly with an analytical framework constructed on the basis of observations; it is intended to provide a means of correlating and interpreting data, and predicting the stability of motions in a combustion chamber. The second is a summary of recent experimental work directed to understanding the flows in dump combustors of the sort used in modern ramjet engines. Much relevant material is not included here, but may be found in the remaining papers of the document cited above. For completeness, we note briefly the substance of those reports. In their summary "Spray Combustion Processes in Ramjet Combustion Instability," Bowman (Stanford), Law (University of California, Davis) and Sirignano (University of California, Irvine) review several aspects of spray combustion relevant to combustion instabilities. The objectives of the works were: (1) to determine the effect of spray characteristics on the energy release pattern in a dump combustor and the subsequent effects on combustion instability; (2) to gain a fundamental understanding of the coupling of the spray vaporization process with an unsteady flow field; and (3) to investigate methods for controlling and enhancing spray vaporization rates in liquid-fueled ramjets. During the past five years considerable progress has been made in applying methods of computational fluid dynamics to the flow in a dump combustor including consequences of energy release due to combustion processes. Jou has summarized work done at Flow Research, Inc. and at the Naval Research Laboratory in his paper "A Summary Report on Large-Eddy Simulations of Pressure Oscillations in a Ramjet Combustor." The serious effects of combustion instabilities on the inlets of ramjet engines were discovered in the late 1970's in experimental work at the Aeropropulsion Laboratory, Wright Field, the Naval Weapons Center and the Marquardt Company. The most thorough laboratory work on the unsteady behavior of inlets has been accomplished at the McDonnell-Douglas Research Laboratory by Sajben who has reviewed the subject in his paper "The Role of Inlet in Ramjet Pressure Oscillations.

Comparison of triton bound state properties using different separable representations of realistic potentials

The quality of two different separable expansion methods ({\sl W} matrix and Ernst-Shakin-Thaler) is investigated. We compare the triton binding energies and components of the triton wave functions obtained in this way with the results of a direct two-dimensional treatment. The Paris, Bonn {\sl A} and Bonn {\sl B} potentials are employed as underlying two-body interactions, their total angular momenta being incorporated up to $j \leq 2$. It is found that the most accurate results based on the Ernst-Shakin-Thaler method agree within 1.5% or better with the two-dimensional calculations, whereas the results for the {\sl W}-matrix representation are less accurate.Comment: 27 pages, 6 postscript figures included, uses psfi

Spin observables for pion production from pd collisions

We have calculated the proton analyzing power A_{y0} of the pion-production reaction from pd collisions for one energy close to threshold and for another in the region of the $\Delta$-resonance. A fair reproduction of the experimental data could be obtained in both cases with a model which includes isoscalar and isovector $\pi N$ rescatterings in s waves, as well as the p-wave rescattering mechanisms mediated by the $\pi NN$ and $\pi N \Delta$ vertices. For the analyzing power at threshold we found that the initial-state interaction (ISI) is also quite important.Comment: Talk at XVIth International Conference on Few-Body Problems in Physics, Taipei, Taiwan, March 6-10 2000. 3 pages, latex, 2 figures -- To appear in Nuclear Physics A -- fleqn.sty and espcrc1.sty require

Strom oder Hafer:die Geschichte der Bonner Pferdebahn

Die Bonner Pferdebahn blieb wegen der allgemeinen Elektrifizierung des öffentlichen Nahverkehrs nur eine Episode der städtischen Verkehrsgeschichte. Schon bei ihrer Eröffnung zeichnete sich der beginnende „Siegeszug“ der elektrischen Straßenbahn ab. ... In der Zeit der privaten Trägerschaft der Bahn von 1891 bis 1905 ... unter der städtischen Betriebsführung bis 1909 standen dieselben wirtschaftlichen Aspekte im Vordergrund. Seit 1902 fuhr die wirtschaftlichere städtische Elektrobahn durch Bonn und präsentierte sich als moderne Alternative zur „gemütlichen“ Pferdebahn. ... Die Tiere verursachten höhere Kosten als die Elektrowagen und konnten deswegen mit ihnen nicht konkurrieren. Zudem entstand in der Bevölkerung eine Wahrnehmungsveränderung gegenüber der Pferdebahn von einem „modernen“ zu einem „rückständigen“ Verkehrsmittel. ... Deshalb wurde die Einstellung des Pferdebetriebes durchweg positiv bewertet. Erst in der Verklärung des „kaiserlichen Bonn“, als die „Welt noch in Ordnung war“, verlieren die Pferdebahn und ihre Tiere jenen rein sachlichen Maßstab, an dem sie zu ihrer Zeit gemessen wurden. In Erinnerungen und Anekdötchen gewinnt die Bahn ein nostalgisches Angesicht, welches bei Berücksichtigung der damaligen Zeitumstände als sehr zweifelhaft zu bezeichnen ist. Das Bild der „behagliche(n)“ Pferdebahn ist zumindest fragwürdig und verschweigt die wirtschaftlichen Gesichtspunkte, die an sie und die Dienstpferde gelegt wurden. In solchen Bildern, die noch heute vorherrschen, dient das Pferd nur als heimeliges, schmückendes Beiwerk und Symbol der „guten, alten Zeit“, während seine wirkliche Lebenssituation unerwähnt bleibt.</und