Deutsche Telekom

About: Deutsche Telekom is a company organization based out in Welwyn Garden City, United Kingdom. It is known for research contribution in the topics: Telecommunications network & Terminal (electronics). The organization has 3473 authors who have published 5208 publications receiving 65429 citations. The organization is also known as: DTAG & German Telecom.

leanEA: A Lean Evolving Algebra Compiler

Abstract: The Prolog program “term_expansion((define C as A with B), (C=>A:-B,!)). term-expansion((transition E if C then D), ((transition E):-C,!,B,A,(transition _))):-rearrange(D,B,A). rearrange((E,F),(C,D),(A,B)):-rearrange(E,C,B), rearrange(F,D,A). rearrange(F:=G, ([G]=>*[E], F=. [C¦D], D=>*B,A=. [C¦B]), asserta(A=>E)). [G¦H]=>*[E¦F]:-(G=>E; G=.[C¦D], D=>*B,A=.[C¦B],A=>E), !,H=>*F. []=>*[]. A=?B:- [A,B]=>*[D,C], D==C.” implements an efficient and flexible simulator for evolving algebra specifications.

The Challenges of CORBA Security

Abstract: Large, distributed applications play an increasingly central role in today’s IT environment The diversity and openness of these systems have given rise to questions of trust and security It is the aim of the project Secure TINA to examine exactly these questions and try to find possible solutions The focus lies on OMG’s Common Object Request Broker Architecture (CORBA) as a basis technology for developing distributed systems and on the Security Service specified for it, since this seems to be the most promising technology in the field The followed approach is thereby twofold At first, a thorough analysis of the specification itself and known implementations thereof is performed, based also on experiences in the broader area of distributed systems security At a second, more practical stage, the attempt to develop an own, prototypical implementation of CORBA Security is undertaken, with the main objective of gaining as much practical experience as possible and experimenting with possible alternatives to find a solution to the problems encountered

A 10 Gb/s silicon bipolar IC for PRBS testing

Abstract: A 10 Gb/s silicon bipolar IC for pseudorandom binary sequence (PRBS) testing was fabricated and tested. The IC features PRBS generation of the sequences of length 2/sup 15/-1 and 2/sup 23/-1 b up to 10 Gb/s according to CCITT recommendations. Furthermore, the IC is capable of analyzing PRB sequences of the same length and generation polynomials so that a full test of components is possible. In addition, a new PRBS test word synchronization can be provided between two chips for external multiplexing of the sequences up to 40 Gb/s. The IC can be connected to a standard PC, so evaluation of the error test data can be performed in a flexible way. The IC was fabricated with the HP25 process of Hewlett Packard company, the chip size is 32 mm/sup 2/, and it consumes 6.2 W at the nominal supply voltage of -5 V.

An Approach for Modeling the Effects of Video Resolution and Size on the Perceived Visual Quality

Abstract: Video-telephony and mobile TV are typical multimedia services which are becoming a part of the everyday life due to the increase in bandwidth availability and also viewing devices with larger screen sizes (smart phone, PDA, etc). To ensure high quality, packet layer parametric quality prediction models for audio-visual services like video-telephony and IPTV video streaming have emerged and are still under development. Those parametric models depend on a set of parameters which have to be tuned for every specific application. In this work, we carry out an experiment to analyze the impact of video resolution and up scaling operation on perceived quality. We could show that the current parametric models can be modified to explicitly integrate the joined effect of resolution and display video size.