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Institution

Alcatel-Lucent

Stuttgart, Germany
About: Alcatel-Lucent is a based out in Stuttgart, Germany. It is known for research contribution in the topics: Signal & Network packet. The organization has 37003 authors who have published 53332 publications receiving 1430547 citations. The organization is also known as: Alcatel-Lucent S.A. & Alcatel.


Papers
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Proceedings Article
23 Aug 1999
TL;DR: This work proposes and evaluates new graphical password schemes that exploit features of graphical input displays to achieve better security than text-based passwords and describes the prototype implementation of one of the schemes on a personal digital assistants (PDAs) namely the Palm PilotTM.
Abstract: In this paper we propose and evaluate new graphical password schemes that exploit features of graphical input displays to achieve better security than text-based passwords. Graphical input devices enable the user to decouple the position of inputs from the temporal order in which those inputs occur, and we show that this decoupling can be used to generate password schemes with substantially larger (memorable) password spaces. In order to evaluate the security of one of our schemes, we devise a novel way to capture a subset of the "memorable" passwords that, we believe, is itself a contribution. In this work we are primarily motivated by devices such as personal digital assistants (PDAs) that offer graphical input capabilities via a stylus, and we describe our prototype implementation of one of our password schemes on such a PDA, namely the Palm PilotTM.

869 citations

Proceedings ArticleDOI
Patrice Godefroid1
01 Jan 1997
TL;DR: This paper discusses how model checking can be extended to deal directly with "actual" descriptions of concurrent systems, e.g., implementations of communication protocols written in programming languages such as C or C++, and introduces a new search technique that is suitable for exploring the state spaces of such systems.
Abstract: Verification by state-space exploration, also often referred to as "model checking", is an effective method for analyzing the correctness of concurrent reactive systems (e.g., communication protocols). Unfortunately, existing model-checking techniques are restricted to the verification of properties of models, i.e., abstractions, of concurrent systems.In this paper, we discuss how model checking can be extended to deal directly with "actual" descriptions of concurrent systems, e.g., implementations of communication protocols written in programming languages such as C or C++. We then introduce a new search technique that is suitable for exploring the state spaces of such systems. This algorithm has been implemented in VeriSoft, a tool for systematically exploring the state spaces of systems composed of several concurrent processes executing arbitrary C code. As an example of application, we describe how VeriSoft successfully discovered an error in a 2500-line C program controlling robots operating in an unpredictable environment.

867 citations

Proceedings ArticleDOI
23 Apr 2006
TL;DR: This paper presents an interference-aware channel assignment algorithm and protocol for multi-radio wireless mesh networks that address this interference problem and demonstrates its practicality through the evaluation of a prototype implementation in a IEEE 802.11 testbed.
Abstract: The capacity problem in wireless mesh networks can be alleviated by equipping the mesh routers with multiple radios tuned to non-overlapping channels However, channel assignment presents a challenge because co-located wireless networks are likely to be tuned to the same channels The resulting increase in interference can adversely affect performance This paper presents an interference-aware channel assignment algorithm and protocol for multi-radio wireless mesh networks that address this interference problem The proposed solution intelligently assigns channels to radios to minimize interference within the mesh network and between the mesh network and co-located wireless networks It utilizes a novel interference estimation technique implemented at each mesh router An extension to the conflict graph model, the multi-radio conflict graph, is used to model the interference between the routers We demonstrate our solution’s practicality through the evaluation of a prototype implementation in a IEEE 80211 testbed We also report on an extensive evaluation via simulations In a sample multi-radio scenario, our solution yields performance gains in excess of 40% compared to a static assignment of channels

861 citations

Journal ArticleDOI
TL;DR: This Account reviews the synthetic methods that have been most useful for preparing a range of semiconductors, including thiophene-based oligomers, several kinds of fused rings, and polymers, and the tradeoff between process efficiency and target purity is emphasized.
Abstract: An essential aspect of the development of organic-based electronics is the synthetic chemistry devised for the preparation of the semiconductor materials responsible for the activity of organic field-effect transistors. Access to organic semiconductors in sufficient purity and variety has led to breakthroughs in solid-state physics and circuit realization. In this Account, we review the synthetic methods that have been most useful for preparing a range of semiconductors, including thiophene-based oligomers, several kinds of fused rings, and polymers. The tradeoff between process efficiency and target purity is emphasized.

860 citations

Journal ArticleDOI
TL;DR: The main focus of this paper is to show the accuracy of the derived analytical model and its applicability to the analysis and optimization of an entire video transmission system.
Abstract: A theoretical analysis of the overall mean squared error (MSE) in hybrid video coding is presented for the case of error prone transmission. Our model covers the complete transmission system including the rate-distortion performance of the video encoder, forward error correction, interleaving, and the effect of error concealment and interframe error propagation at the video decoder. The channel model used is a 2-state Markov model describing burst errors on the symbol level. Reed-Solomon codes are used for forward error correction. Extensive simulation results using an H.263 video codec are provided for verification. Using the model, the optimal tradeoff between INTRA and INTER coding as well as the optimal channel code rate can be determined for given channel parameters by minimizing the expected MSE at the decoder. The main focus of this paper is to show the accuracy of the derived analytical model and its applicability to the analysis and optimization of an entire video transmission system.

833 citations


Authors

Showing all 37011 results

NameH-indexPapersCitations
George M. Whitesides2401739269833
Yoshua Bengio2021033420313
John A. Rogers1771341127390
Zhenan Bao169865106571
Thomas S. Huang1461299101564
Federico Capasso134118976957
Robert S. Brown130124365822
Christos Faloutsos12778977746
Robert J. Cava125104271819
Ramamoorthy Ramesh12264967418
Yann LeCun121369171211
Kamil Ugurbil12053659053
Don Towsley11988356671
Steven P. DenBaars118136660343
Robert E. Tarjan11440067305
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
20231
202212
202130
202050
201983
2018215