Alcatel-Lucent

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.

Password hardening based on keystroke dynamics

Abstract: We present a novel approach to improving the security of passwords. In our approach, the legitimate user’s typing patterns (e.g., durations of keystrokes and latencies between keystrokes) are combined with the user’s password to generate a hardened password that is convincingly more secure than conventional passwords alone. In addition, our scheme automatically adapts to gradual changes in a user’s typing patterns while maintaining the same hardened password across multiple logins, for use in file encryption or other applications requiring a long-term secret key. Using empirical data and a prototype implementation of our scheme, we give evidence that our approach is viable in practice, in terms of ease of use, improved security, and performance.

Rheology of Ordered and Disordered Symmetric Poly(Ethylenepropylene)-Poly(ethylethylene) Diblock Copolymers

Abstract: The linear dynamic mechanical properties of nearly symmetric 55:45 PEP-PEE diblock copolymers and the corresponding homopolymers are described. The results show the influence of composition fluctuations on the rheological properties around the microphase separation transition and confirms the first-order nature of this transition for hearly symmetric samples dynamic shear measurements obtained after a temperature quench from just above to just below the microphase separation temperature demonstrate the ability to supercool the disordered material and provide a measure of the subsequent ordering kinetics

Electric polarization rotation in a hexaferrite with long-wavelength magnetic structures.

Abstract: We report on the control of electric polarization (P) by using magnetic fields (B) in a hexaferrite having magnetic order above room temperature (RT). The material investigated is hexagonal Ba0.5Sr1.5Zn2Fe12O22, which is a nonferroelectric helimagnetic insulator in the zero-field ground state. By applying B, the system undergoes successive metamagnetic transitions, and shows concomitant ferroelectric order in some of the B-induced phases with long-wavelength magnetic structures. The magnetoelectrically induced P can be rotated 360 degrees by external B. This opens up the potential for not only RT magnetoelectric devices but also devices based on the magnetically controlled electro-optical response.

Model reduction methods based on Krylov subspaces

Abstract: In recent years, reduced-order modelling techniques based on Krylov-subspace iterations, especially the Lanczos algorithm and the Arnoldi process, have become popular tools for tackling the large-scale time-invariant linear dynamical systems that arise in the simulation of electronic circuits. This paper reviews the main ideas of reduced-order modelling techniques based on Krylov subspaces and describes some applications of reduced-order modelling in circuit simulation.

Scheduling Flexible Servers with Convex Delay Costs: Heavy-Traffic Optimality of the Generalized cµ-Rule

Abstract: We consider a queueing system with multitype customers and flexible (multiskilled) servers that work in parallel. IfQ iis the queue length of typei customers, this queue incurs cost at the rate ofC i ( Q i ), whereC i (.) is increasing and convex. We analyze the system in heavy traffic (Harrison and Lopez 1999) and show that a very simple generalizedcµ-rule (Van Mieghem 1995) minimizes both instantaneous and cumulative queueing costs, asymptotically, over essentially all scheduling disciplines, preemptive or non-preemptive. This rule aims at myopically maximizing the rate of decrease of the instantaneous cost at all times, which translates into the following: when becoming free, serverj chooses for service a typei customer such thati ? arg max i C' i ( Q i )µ ij , where µ ijis the average service rate of typei customers by serverj.An analogous version of the generalizedcµ-rule asymptotically minimizes delay costs. To this end, let the cost incurred by a typei customer be an increasing convex functionC i ( D) of its sojourn timeD. Then, serverj always chooses for service a customer for which the value ofC' i ( D) µ ijis maximal, whereD andi are the customer's sojourn time and type, respectively.