Conflict Visualization for Collaborative Multi-user Applications

If a collaborative multi-user application allows concurrent or asynchronous manipulation of shared data, user actions may conflict. While conflicts can be resolved syntactically by concurrency control, the system is not able to interpret actions, and the determined result might violate the users' intentions. We propose a visual feedback scheme so that users are aware of critical situations and may react accordingly. In our approach, the action history is represented as an interactive timeline that can be analyzed by the user. A prototype was realized for a shared whiteboard application

RTP/I Payload Type Definition for Application Launch Tools

This document specifies an application-level protocol (i.e., payload type) for application launch tools using the Real-Time Protocol for Distributed Interactive Media (RTP/I). RTP/I defines a standardized framing for the transmission of application data and provides protocol mechanisms that are universally needed for the class of distributed interactive media. An application launch tool is used to synchronously start applications in collaborative environments, i.e., a participant can trigger the simultaneous execution of a program at all involved sites. This document specifies how to employ an application launch tool with RTP/I and defines application data units (ADUs) for application launch tool operations. This protocol definition allows standardized communication between different application launch tool implementations

RTP/I Payload Type Definition for Chat Tools

This document specifies an application-level protocol (i.e., payload type) for chat tools using the Real Time Protocol for Distributed Interactive Media (RTP/I). RTP/I defines a standardized framing for the transmission of application data and provides protocol mechanisms that are universally needed for the class of distributed interactive media. A chat tool provides an instant messaging service among an arbitrary number of users. This documents specifies how to employ a chat tool with RTP/I and defines application data units (ADUs) for chat operations. This protocol definition allows standardized collaboration between different chat implementations

RTP/I Payload Type Definition for Feedback Tools

This document specifies an application-level protocol (i.e., payload type) for feedback tools using the Real Time Protocol for Distributed Interactive Media (RTP/I). RTP/I defines a standardized framing for the transmission of application data and provides protocol mechanisms that are universally needed for the class of distributed interactive media. A feedback tool is used in synchronous collaborative environments for permanent feedback about certain criteria (e.g., audio quality). This document specifies how to employ a feedback tool with RTP/I and defines application data units (ADUs) for feedback tool operations. This protocol definition allows standardized communication between different feedback tool implementations

RTP/I Payload Type Definition for Telepointers

This document specifies an application-level protocol (i.e., payload type) for telepointers using the Real Time Protocol for Distributed Interactive Media (RTP/I). RTP/I defines a standardized framing for the transmission of application data and provides protocol mechanisms that are universally needed for the class of distributed interactive media. A telepointer creates a common point of reference in distributed (i.e., multi-user) applications by visualizing mouse movements of remote session participants. Telepointers are used in conjunction with other distributed interactive media such as shared whiteboards and distributed virtual environments. This documents specifies how to employ two-dimensional telepointers with RTP/I and defines application data units (ADUs) for telepointer operations. This protocol definition allows standardized collaboration between different telepointer implementations

RTP/I Payload Type Definition for Hand-Raising Tools

This document specifies an application-level protocol (i.e., payload type) for hand-raising tools using the Real Time Protocol for Distributed Interactive Media (RTP/I). RTP/I defines a standardized framing for the transmission of application data and provides protocol mechanisms that are universally needed for the class of distributed interactive media. A hand-raising tool can support collaboration between spatially separated users. In a video conference, for example, a hand-raising tool can be used to coordinate different speakers. This documents specifies how to employ a hand-raising tool with RTP/I and defines application data units (ADUs) for hand-raising tool operations. This protocol definition allows standardized collaboration between different hand-raising tool implementations

The treatment of chronic hepatitis C virus infection in HIV co-infection

Chronic HCV co-infection is present in up to one third of HIV-positive patients in Europe. In recent years, apart from the traditional transmission route of intravenous drug abuse, outbreaks of sexually transmitted acute HCV infections, mainly among HIV-positive men who have sex with men, have contributed to the overall disease burden

Lehrszenarien-übergreifende Erzeugung und Verwendung Multimedialer Teachware

Das Erstellen multimedialer Lehrdokumente ist ein aufwendiger Prozeß. In der traditionellen Lehre werden für verschiedenen Lehrszenarien (Vorlesung, Nachbearbeitung durch den Studenten, etc.) oft unterschiedliche Dokumente erstellt, die denselben Stoff behandeln. Weiterhin entstehen während einer Vorlesung durch die Erklärungen des Dozenten implizit Dokumente, die auch in anderen Lehrszenarien sinnvoll eingesetzt werden können. In diesem Artikel wird beschrieben, wie die in Lehrveranstaltungen entstehenden Dokumente aufgezeichnet und auf einem Server bereitgestellt werden. Mit dem vorgestellten Verfahren können die Aufzeichnungen flexibel mit zusätzlichen multimedialen Inhalten zu einer Computer-Based-Training-Einheit verknüpft werden. Dadurch ist es möglich, Dokumente effektiv sowohl in synchronen als auch in asynchronen Lehrszenarien zu einzusetzen

Phosphate glasses and glass-ceramics for medical applications

Modified calcium phosphate glass Systems meet the requirements for the development of different biomaterials. Bioactive, longterm stable phosphate glass-ceramics and resorbable phosphate glasses were prepared in the Systems P₂O₅ - CaO - Al₂O₃ - Na₂O and P₂O₅ - CaO - MgO - Na₂O . Due to their high thermal expansion coefficients the bioactive phosphate glass-ceramics are excellently suited for coating metals. Using a salt-sintering process, porous resorbable glasses can be obtained. The properties of glassceramic coatings on cobalt/chromium alloys and the production of porous resorbable phosphate invert glasses are described