10,339 research outputs found
THREAT TO FREE INFORMATION AND FREEDOM OF INFORMATION
“Imagine a world in which every single person on the planet is given free access to the sum of all human knowledge. That’s what we’re doing.” At a time when internet access is widely available, information is spread around the globe rapidly. This development enables people in various parts of the world to gain access to information faster than ever before imagined. A lot of the information on the net comes free of charge, which allows access regardless of money. However, as everybody is able to provide information more or less anonymously on the net we have to focus on the quality of the information supplied.freedom of information, objectivity, anonimyty, credibility, censorship
Ecology and structure of Drosophyllum lusitanicum (l.) Links populations in the south-west of the Iberian Peninsula
Ecología y estructura de poblaciones de Drosophyllum lusitanicum (L.) Link en el suroeste de la Península Ibérica. Drosophyllum lusitanicum es una planta autógama y nautocórica cuyo tamaño y estructura de población han sido estudiados en dos áreas del suroeste de la Península Ibérica. Su carácter cenológico se documenta mediante una tabla fitosociológica sintética basada en inventarios ya publicados y datos nuevos. En la Sierra de Monchique (Portugal) se cartografían 21 poblaciones cuyo tamaño medio es de 165 individuos. Sin embargo, en el Campo de Gibraltar (España), se encontró la población de mayor tamaño, con varios miles de individuos en la Sierra del Aljibe. Aquí se estudió el tamaño de las plantas, el diámetro de la roseta basal y el grado de lignificación de 700 individuos, lo que se utilizó como indicador indirecto de la estructura de edades de 19 poblaciones.Drosophyllum lusitanicum tiene un cierto carácter pionero. Se presenta mayoritariamente en los brezales aclarados de Ericion umbellatae (Stauracantho-Drosophylletum, Querco lusitanicae-Stauracanthetum, Genisto tridentis-Stauracanthetum, etc.). Es capaz de colonizar medios alterados, como cunetas de carreteras y cortafuegos, y es un apófito en las comunidades basales de Drosophyllo-[Stauracanthenion], siendo además esta especie favorecida por los frecuentes incendios de la zona. En los alcornocales abiertos de Myrto-Quercetum suberis y en los brezales densos de Erica australis predominan los individuos grandes, siendo éstas poblaciones maduras. Finalmente, se aportan algunos datos poco conocidos de su reproducción y ecología que indican la necesidad de un mayor esfuerzo para la conservación del área portuguesa estudiada
The impact of the introduction of the Euro on firms' expectations concerning export behavior, product innovation and foreign competition - An empirical assessment of the German business-related services sector
This paper analyses the degree to which firms expect to be able to enter new markets, to develop new products and to contend with new foreign competition after the introduction of the Euro. Panel data taken from a quarterly business survey in the service sector are used for the empirical analysis. East German firms do not differ from their West German competitors in their expectations that the Euro will increase export activity and product innovation, but significantly more East German firms expect new foreign competitors to enter the home market. The impact of the Euro on firms' expectations of entering new markets and developing new products is stronger for firms which already export than for those who do not. Further, the degree of preparation for the Euro plays a significant role in firms' market expectations. --European Monetary Union,Euro,business-related services,binary probit model,export,foreign competition
Controlled nonuniformity in macroporous silicon pore growth
Photoelectrochemical etching of uniform prestructured silicon wafers in hydrofluoric acid containing solutions yields periodic structures that can be applied to two- and three-dimensional photonic crystals or microfluidics. Here we demonstrate experimentally macroporous silicon etching initiated by a nonuniform predefined lattice. For conveniently chosen parameters we observe a stable growth of pores whose geometrical appearance depends strongly on the spatially different nucleation conditions. Moreover, we show preliminary results on three-dimensionally shaped pores. This material can be used to realize hybrid photonic crystal structures and incorporate waveguides in three-dimensional photonic crystals
Electron-translation effects in heavy-ion scattering
The origin and importance of electron-translation effects within a molecular description of electronic excitations in heavy-ion collisions is investigated. First, a fully consistent quantum-mechanical description of the scattering process is developed; the electrons are described by relativistic molecular orbitals, while the nuclear motion is approximated nonrelativistically. Leaving the quantum-mechanical level by using the semiclassical approximation for the nuclear motion, a set of coupled differential equations for the occupation amplitudes of the molecular orbitals is derived. In these coupled-channel equations the spurious asymptotic dynamical couplings are corrected for by additional matrix elements stemming from the electron translation. Hence, a molecular description of electronic excitations in heavy-ion scattering has been achieved, which is free from the spurious asymptotic couplings of the conventional perturbated stationary-state approach. The importance of electron-translation effects for continuum electrons and positrons is investigated. To this end an algorithm for the description of continuum electrons is proposed, which for the first time should allow for the calculation of angular distributions for δ electrons. Finally, the practical consequences of electron-translation effects are studied by calculating the corrected coupling matrix elements for the Pb-Cm system and comparing the corresponding K-vacancy probabilities with conventional calculations. We critically discuss conventional methods for cutting off the coupling matrix elements in coupled-channel calculations
Web Service Retrieval by Structured Models
Much of the information available on theWorldWideWeb cannot effectively be found by the help of search engines because the information is dynamically generated on a user’s request.This applies to online decision support services as well as Deep Web information. We present in this paper a retrieval system that uses a variant of structured modeling to describe such information services, and similarity of models for retrieval. The computational complexity of the similarity problem is discussed, and graph algorithms for retrieval on repositories of service descriptions are introduced. We show how bounds for combinatorial optimization problems can provide filter algorithms in a retrieval context. We report about an evaluation of the retrieval system in a classroom experiment and give computational results on a benchmark library.Economics ;
Welfare effects of the GATT system
The GATT Conference of Ministers scheduled for November will have to deal with those developments of recent years which have given cause to believe that GATT is increasingly being adapted to the trade practices of its signatories rather than itself serving as their guiding principle. Does such a trend in fact exist and, if so, what are its effects on the member states' welfare
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