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Einsatz umweltverträglicher Tenside in Formulierungen am Beispiel von Glyphosat und Prochloraz
(2000)
Multimediaprojectors require sophisticated image processing realized on limited board space. An architecture is presented that combines available components and a dedicated display controller for a flexible, compact and cost efficient display electronic. A basic version of the display controller is available as an ASIC, an advanced version has been prototyped as an FPGA.
To provide seamless handoffs is an important task of cellular systems. A user of a real-time conversation on a mobile terminal should not notice when moving from one base station to another one. In this paper we address handoff procedures in a scenario where the radio access network is assumed to be IP-based, i.e., IP is used up to the base stations, and the mobile terminal runs a Mobile IP client. First we will motivate the need for differentiation of fast handoffs and seamless handoffs. Then we will survey some previously proposed micro-mobility extensions; thereby we will address the question of what degree of micro-mobility support is needed in the typical structure of a radio access network. The main part of this paper then discusses network-initiated/assisted handoffs in combination with Mobile IP. Here, we aim to bring together ideas of 2G/3G systems and of IP-based approaches.
The Internet Engineering Task Force (IETF) is currently working on the development of Differentiated Services (DiffServ). DiffServ seems to be a promising technology for next-generation IP networks supporting Quality-of-Services (QoS). Emerging applications such as IP telephony and time-critical business applications can benefit significantly from the DiffServ approach since the current Internet often can not provide the required QoS. This paper describes an implementation of Differentiated Services for Linux routers and end systems. The implementation is based on the Linux traffic control package and is, therefore, very flexible. It can be used in different network environments as first-hop, boundary or interior router for Differentiated Services. In addition to the implementation architecture, the paper describes performance results demonstrating the usefulness of the DiffServ concept in general and the implementation in particular.
Recent developments in the standardization of the future Internet (driven by the IETF) and next generation telecom networks (driven by 3GPP) show a convergence towards each other. While it is currently unknown if and to what extend this development leads to a unified technical approach (in terms of signaling, routing, mobility management, charging and security) for both real-time (voice / video) and non-real-time (data) networks, the vision of an All-IP-based communication environment for all classes of traffic is one relevant option to look at.
We report the status of a search for pulsars in the Galactic Centre, using a completely revised and improved high-sensitivity doublehorn system at 4.85-GHz. We also present calculations about the success rate of periodicity searches for such a survey, showing that in contrast to conclusions in recent literature pulsars can be indeed detected at the chosen search frequency.
Bei der Datenübertragung im Internet ist es wünschenswert, daß unterschiedliche Datenpackete unterschiedlich behandelt werden können, damit für die zeitkritischen Anwendungen wie Internet-Telefonie die größere Priorität gewährleisten könnte. Erst dann kann ein Netzbetreiber seinen Kunden verschiedene Dienstqualitäten anbieten. Zwei grundsätzliche Mechanismen existieren, um dem Netzwerk solche Anforderungen mitzuteilen: explizit, indem vor der eigentlichen Datenübertragung Kotrollnachrichten ausgetauscht werden; implizit, indem jedes Datenpacket eine Kennzeichnung erhält. Der zweite, Differentiated Services(DS), Ansatz ist Thema dieses Referates. Bei DS wird jedem Packet den sogenannten DS-Codepoint (DSCP) im IP-Header zugewiesen, und dementsprechend erfährt ein Datenpaket eine bestimmte Behandlung durch einen DS-fähigen Router. Drei unterschiedliche Dienstklassen wurde bisher spezifiziert: Best-Effort entspricht dem derzeit im Internet verwendeten Mechanismus; Premium-Service entspricht einer virtuellen Mietleitung und soll eine rasche Weiterleitung von Paketen gewährleisten; Datenpakete mit Assured Forwarding Service (AFS) sollen besser behandelt werden als Best-Effort. Bei AFS wurden insgesamt drei Verlustklassen und vier Weiterleitungsklassen definiert. Es wird auch verschiedene Typ von DS-Router vorgestellt und diskutiert. Der praktische Einsatz erfolgte bisher immer in Laborumgebung (Uni Bern, Uni Karlsruhe, EPFL, Forschungszentrum NEC Research), größere Feldversuche stehen noch aus.