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.

HAWAII: a domain-based approach for supporting mobility in wide-area wireless networks

Abstract: Mobile IP is the current standard for supporting macromobility of mobile hosts. However, in the case of micromobility support, there are several competing proposals. We present the design, implementation and performance evaluation of HAWAII (handoff-aware wireless access Internet infrastructure), a domain-based approach for supporting mobility. HAWAII uses specialized path setup schemes which install host-based forwarding entries in specific routers to support intra-domain micromobility. These path setup schemes deliver excellent performance by reducing mobility related disruption to user applications. Also, mobile hosts retain their network address while moving within the domain, simplifying quality-of-service (QoS) support. Furthermore, reliability is achieved through maintaining soft-state forwarding entries for the mobile hosts and leveraging fault detection mechanisms built in existing intra-domain routing protocols. HAWAII defaults to using Mobile IP for macromobility, thus providing a comprehensive solution for mobility support in wide-area wireless networks.

Systematic treatment of displacements, strains, and electric fields in density-functional perturbation theory

Abstract: The methods of density-functional perturbation theory may be used to calculate various physical response properties of insulating crystals including elastic, dielectric, Born charge, and piezoelectric tensors. These and other important tensors may be defined as second derivatives of an appropriately defined energy functional with respect to atomic-displacement, electric-field, or strain perturbations, or as mixed derivatives with respect to two of these perturbations. The resulting tensor quantities tend to be coupled in complex ways in polar crystals, giving rise to a variety of variant definitions. For example, it is generally necessary to distinguish between elastic tensors defined under different electrostatic boundary conditions, and between dielectric tensors defined under different elastic boundary conditions. Here, we describe an approach for computing all of these various response tensors in a unified and systematic fashion. Applications are presented for two materials, hexagonal ZnO and rhombohedral $\mathrm{Ba}\mathrm{Ti}{\mathrm{O}}_{3}$, at zero temperature.

Spontaneously organized molecular assemblies. 2. Quantitative infrared spectroscopic determination of equilibrium structures of solution-adsorbed n-alkanoic acids on an oxidized aluminum surface

Abstract: Determination de la structure des couches monomoleculaires des acides alcanoiques, a 16-22 atomes de carbone, termines par des groupes methyle, vinyle ou propargyle, formees lors de l'adsorption sur de l'oxyde d'Al, a partir d'une solution dans l'hexadecane

Nonlinear limits to the information capacity of optical fibre communications.

Abstract: The exponential growth in the rate at which information can be communicated through an optical fibre is a key element in the 'information revolution' However, as for all exponential growth laws, physical limits must be considered The nonlinear nature of the propagation of light in optical fibre has made these limits difficult to elucidate Here we use a key simplification to investigate the theoretical limits to the information capacity of an optical fibre arising from these nonlinearities The success of our approach lies in relating the nonlinear channel to a linear channel with multiplicative noise, for which we are able to obtain analytical results In fundamental distinction to linear channels with additive noise, the capacity of a nonlinear channel does not grow indefinitely with increasing signal power, but has a maximal value The ideas presented here may have broader implications for other nonlinear information channels, such as those involved in sensory transduction in neurobiology These have been often examined using additive noise linear channel models but, as we show here, nonlinearities can change the picture qualitatively

Comparison of classifier methods: a case study in handwritten digit recognition

Abstract: This paper compares the performance of several classifier algorithms on a standard database of handwritten digits. We consider not only raw accuracy, but also training time, recognition time, and memory requirements. When available, we report measurements of the fraction of patterns that must be rejected so that the remaining patterns have misclassification rates less than a given threshold.