Kinder online 2004 : Internetnutzung von Kindern ; Studie der Agentur für neue Medien NEUE DIGITALE in Zusammenarbeit mit dem Frankfurter Kinderbüro und der Johannes Gutenberg-Universität Mainz

Die Studie „Kinder Online 2004“ soll Aufschluss darüber geben, wie Kinder heute den Computer und das Internet in ihrer Freizeit nutzen: den Stellenwert der digitalen Medien identifizieren und über das Internet-Verhalten der Kinder sowie über ihre Präferenzen informieren

Kinetics of the oxidative decolorization of some organic dyes utilizing Fenton-like reaction in water

AbstractThe decolorization kinetics of some organic pollutants in water such as commercial dyes, namely, Malachite green (MG), Rhodamine B (RB), Methylene blue (MB) and Crystal violet (CV) were studied using a Fenton-like reagent. The effects of different parameters like the initial dye concentration, Fe3+, concentration of H2O2, pH of the solution, reaction temperature, and added electrolytes on the kinetics were determined. The results indicate that the optimum pH for the decolorization of all dyes examined is in the range between 3 and 4. The rate of decolorization showed remarkable dependence on the initial Fe3+ concentration. Using dilute dye solutions in the range of (0.30–1.50×10−5 moldm−3) the rate increased as the Fe3+ concentration was increased from 1.5×10−4 to 6.0×10−4moldm−3, and becomes practically constant when it exceeds 6.0×10−4moldm−3. Below 1.5×10−4moldm−3 of Fe3+, the decolorization reaction is too sluggish to account for any practical significance. But the decolorization rate of all examined dyes decreased at high Fe3+ concentrations (⩾1.0×10−3moldm−3). There is an optimum H2O2 concentration in the range of 0.01–0.04moldm−3 that is effective for decolorization of the dyes. It was observed that the presence of halide salts at the same concentration level substantially decreased the rate and the extent of decolorization, whereas for nitrate salt, there is an increase in the extent of dye decolorization. An increase in the extent of decolorization of the dye was observed when the reaction temperature was raised. The results will be useful for designing the treatment systems of various dye-containing wastewaters. It was also found that the decolorization of the dyes undergoes a fast reaction than the mineralization

Jahresbericht : 2003 / IWF Wissen und Medien gGmbH

Einschl.: Anlage "Bericht des Beirats" : Bericht des Beirats der IWF Wissen und Medien gGmbH über die Arbeit in der Periode 2002/200

<i>No Pass Laws Here!</i> Internal Border Controls and the Global ‘Hostile Environment'

This article explores internal border controls in 1980s Britain, examining how they were conceptualised and resisted by a group of activists, the No Pass Laws Here! Group. Drawing on archival research conducted at the Hull History Centre and the Institute of Race Relations and focusing analysis on the Group’s public-facing information leaflets and bulletins, this article explores how internal border controls created differentiated access to employment and the welfare state, targeting migrant and racialised residents and citizens. The No Pass Laws Here! Group’s framing and analysis, in particular their use of pass laws as a frame through which to apprehend the spread of internal border controls, this article argues, allows us to draw out the continuities between policies developed to maintain colonial rule and those present in the metropole

Patients Not Passports: Learning from the international struggle for universal healthcare

This report focuses on the set of policies introduced as part of the government’s Hostile Environment immigration policies – which restrict access to public services and criminalise everyday activities – to expand border enforcement into the National Health Service (NHS) and restrict access to healthcare

Comparison of Code-Pass-Skipping Strategies for Accelerating a JPEG 2000 Decoder

Abstract Code-Pass-Skipping allows a JPEG 2000 decoder to be accelerated by sacrificing the output precision. This paper presents an evaluation on how the speed gain can be maximized and the quality loss minimized. In particular, the scenario of rendering a 24-bit preview of a Digital Cinema Package (DCP) with the maximum permitted bitrate is examined. A comparison shows that a new proposed strategy outperforms the reference implementation from Kakadu Software v6 by up to 1 dB. Furthermore, it is shown what speed gain can be achieved for a given acceptable quality loss

Evaluation of 3D-Video Compression for Automotive Stereo Vision Systems

Abstract This paper is an evaluation of the distribution of quantized coefficients resulting from the disparity of an automotive stereo vision system. The system captures the scene with two cameras, computes the disparity with Semi-Global Matching and encodes the left view and the disparity for transmission. Real world and synthetic video sequences were used to evaluate the coefficient distributions of the system under normal and challenging weather conditions. The results show, that the quantized disparity coefficients in frequency space have consistently lower entropy compared to the coefficients of the video scenes. Therefore, it is advantageous for the system to compress the disparity instead of one of the two video streams. Introduction Motivation Driver assistance systems depend on a variety of sensors, interconnected with electronic control units (ECUs ). In order to get a settled and agreed interface definition, the International Organization for Standardization (ISO) initiated the standardization process of the video communication interface for cameras in road vehicles low-voltage differential signaling Figure 1 Stereo Vision System: The system captures the scene with two cameras, computes the disparity and encodes the left view and the disparity for transmission to the ECU. With the disparity information an automotive function can calculate the distance Z to an obstacle. We already examined the peak signal to noise ratio of the left video and the mean disparity error of the system under different rate allocations between the video and disparity streams (see Related Work In [5] the distribution of DCT-coefficients in the field of image compression is examined and an approximation of the AC-coefficients with Laplace distributions is proposed. The work o