Voneinander Lernen: Ein Handbuch für Sprachlehrerverbände

The publication is aimed at those involved in the running of language teacher associations at international, national, regional and local levels. This may include paid employees or, more frequently, volunteers. It provides guidance on the effective running and networking of associations. It encourages language teacher associations to collaborate in order to support teachers more effectively, and to contribute to improvements in the quality of language teaching. It enables language teachers across the world to share their own ideas, to be involved in research, and to learn about the cutting-edge work of the ECML and its European projects

Apprendre les uns des autres: Manuel pour les associations de professeurs de langues

The publication is aimed at those involved in the running of language teacher associations at international, national, regional and local levels. This may include paid employees or, more frequently, volunteers. It provides guidance on the effective running and networking of associations. It encourages language teacher associations to collaborate in order to support teachers more effectively, and to contribute to improvements in the quality of language teaching. It enables language teachers across the world to share their own ideas, to be involved in research, and to learn about the cutting-edge work of the ECML and its European project

Learning from each other: A handbook for language teacher associations

The publication is aimed at those involved in the running of language teacher associations at international, national, regional and local levels. This may include paid employees or, more frequently, volunteers. It provides guidance on the effective running and networking of associations. It encourages language teacher associations to collaborate in order to support teachers more effectively, and to contribute to improvements in the quality of language teaching. It enables language teachers across the world to share their own ideas, to be involved in research, and to learn about the cutting-edge work of the ECML and its European project

Structure analysis of interstellar clouds: I. Improving the Delta-variance method

The Delta-variance analysis, has proven to be an efficient and accurate method of characterising the power spectrum of interstellar turbulence. The implementation presently in use, however, has several shortcomings. We propose and test an improved Delta-variance algorithm for two-dimensional data sets, which is applicable to maps with variable error bars and which can be quickly computed in Fourier space. We calibrate the spatial resolution of the Delta-variance spectra. The new Delta-variance algorithm is based on an appropriate filtering of the data in Fourier space. It allows us to distinguish the influence of variable noise from the actual small-scale structure in the maps and it helps for dealing with the boundary problem in non-periodic and/or irregularly bounded maps. We try several wavelets and test their spatial sensitivity using artificial maps with well known structure sizes. It turns out that different wavelets show different strengths with respect to detecting characteristic structures and spectral indices, i.e. different aspects of map structures. As a reasonable universal compromise for the optimum Delta-variance filter, we propose the Mexican-hat filter with a ratio between the diameters of the core and the annulus of 1.5.Comment: Accepted for publication in A&A, Sect. 1

Pion and Kaon Spectra from Distributed Mass Quark Matter

After discussing some hints for possible masses of quasiparticles in quark matter on the basis of lattice equation of state, we present pion and kaon transverse spectra obtained by recombining quarks with distributed mass and thermal cut power-law momenta as well as fragmenting by NLO pQCD with intrinsic $k_T$ {and nuclear} broadening.Comment: Talk given at SQM 200

A Fractal Analysis of the HI Emission from the Large Magellanic Cloud

A composite map of HI in the LMC using the ATCA interferometer and the Parkes multibeam telescope was analyzed in several ways in an attempt to characterize the structure of the neutral gas and to find an origin for it. Fourier transform power spectra in 1D, 2D, and in the azimuthal direction were found to be approximate power laws over 2 decades in length. Delta-variance methods also showed the same power-law structure. Detailed models of these data were made using line-of-sight integrals over fractals that are analogous to those generated by simulations of turbulence with and without phase transitions. The results suggested a way to measure directly for the first time the line-of-sight thickness of the cool component of the HI disk of a nearly face-on galaxy. The signature of this thickness was found to be present in all of the measured power spectra. The character of the HI structure in the LMC was also viewed by comparing positive and negative images of the integrated emission. The geometric structure of the high-emission regions was found to be filamentary, whereas the geometric structure of the low-emission (intercloud) regions was found to be patchy and round. This result suggests that compressive events formed the high-emission regions, and expansion events, whether from explosions or turbulence, formed the low-emission regions. The character of the structure was also investigated as a function of scale using unsharp masks. All of these results suggest that most of the ISM in the LMC is fractal, presumably the result of pervasive turbulence, self-gravity, and self-similar stirring.Comment: 30 pages, 21 figures, scheduled for ApJ Vol 548n1, Feb 10, 200

A Turbulent Origin for Flocculent Spiral Structure in Galaxies

The flocculent structure of star formation in 7 galaxies has a Fourier transform power spectrum for azimuthal intensity scans with a power law slope that increases systematically from -1 at large scales to -1.7 at small scales. This is the same pattern as in the power spectra for azimuthal scans of HI emission in the Large Magellanic Clouds and for flocculent dust clouds in galactic nuclei. The steep part also corresponds to the slope of -3 for two-dimensional power spectra that have been observed in atomic and molecular gas surveys of the Milky Way and the Large and Small Magellanic Clouds. The same power law structure for star formation arises in both flocculent and grand design galaxies, which implies that the star formation process is the same in each. Fractal Brownian motion models that include discrete stars and an underlying continuum of starlight match the observations if all of the emission is organized into a global fractal pattern with an intrinsic 1D power spectrum having a slope between 1.3 and 1.8. We suggest that the power spectrum of optical light in galaxies is the result of turbulence, and that large-scale turbulent motions are generated by sheared gravitational instabilities which make flocculent spiral arms first and then cascade to form clouds and clusters on smaller scales.Comment: accepted for ApJ, 31 pg, 9 figure

A Fractal Origin for the Mass Spectrum of Interstellar Clouds: II. Cloud Models and Power Law Slopes

Three-dimensional fractal models on grids of 200**3 pixels are generated from the inverse Fourier transform of noise with a power law cutoff, exponentiated to give a log normal distribution of density. The fractals are clipped at various intensity levels and the mass and size distribution functions of the clipped peaks and their subpeaks are determined. These distribution functions are analogous to the cloud mass functions determined from maps of the fractal interstellar medium using various thresholds for the definition of a cloud. The model mass functions are found to be power laws with powers ranging from -1.6 to -2.4 in linear mass intervals as the clipping level increases from 0.03 to 0.3 of the peak intensity. The low clipping value gives a cloud filling factor of 0.1 and should be a good model for molecular cloud surveys. The agreement between the mass spectrum of this model and the observed cloud and clump mass spectra suggests that a pervasively fractal interstellar medium can be interpreted as a cloud/intercloud medium if the peaks of the fractal intensity distribution are taken to be clouds. Their mass function is a power law even though the density distribution function in the gas is a log-normal. This is because the size distribution function of the clipped clouds is a power law, and with clipping, each cloud has about the same average density. A similar result would apply to projected clouds that are clipped fractals, giving nearly constant column densities for power law mass functions. The steepening of the mass function for higher clip values suggests a partial explanation for the steeper slope of the mass functions for star clusters and OB associations, which sample denser regions of interstellar gas.Comment: accepted for ApJ 564, January 10, 2002, 8 figure