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Audience research is a vital part of TV and radio broadcasting, as well as of the more recent forms of media content delivery, such as the Internet, IPTV, mobile phones, Personal Video Recorders (PVRs) and portable media viewers. The uses of audience research range from self-promotion to refining service offerings and setting advertising rates. Without reliable audience data, many businesses will be reluctant to participate in the new platforms. This paper describes an end-to-end system for convergent audience measurement focused on IPTV but covering also terrestrial, cable, satellite and mobile broadcasting. We created the audience measurement system from the elaboration of a logical architectural model and a common data model which can be applied to any media scenario. We implemented this logical and data model in stationary and mobile media receivers (in the paper the particular case of IPTV is extensively explained). In addition user consumption is modeled and metrics are provided for user media consumption profiling and impact quantification in IPTV environments. Index Terms--Audience measurement, content consumption measurement, IPTV, logical and data modeling, middleware, user profile.

This paper provides a technique to determine the minimum required measurement set to ensure observability in state estimation even if any h meters fail. The technique relies on solving a nonlinear integer programming problem. The proposed procedure is illustrated through a simple example and three case studies based on the IEEE Test Systems. Conclusions are finally drawn. Index Terms--Binary variables, linear algebra, observability analysis, power system state estimation.

Motion description is a key element in region-based video,coding approaches, becoming essential for low and very low bit-rate transmissions. Among the different advanced motio-description approaches, multivector motion description (MMD) models the region motion through a variable number of motion vectors (MVs) applied on specific region points called control points (CPs). However, its application for region-based video coding would require the transmission of both MVs and CPs in order to adequately compensate each region motion. Here, a region-based control point determination strategy for MMD is proposed, which is strictly based on region contour information and the application of motion-interpolation accuracy constraints to drive the CP's location procedure. This approach offers two main advantages while keeping a reasonable computational cost: 1) it is able to operate on arbitrary-shaped regions of the image and 2) it allows the complete elimination of the transmission of any information related to the number and position of the CPs. Index Terms--Control points, interpolation, multivector motion estimation and compensation, spatial transformations, video coding.

An intra-frame segmentation strategy to assist region-based motion estimation and compensation is presented. It is based on the multiresolution application of a histogram clustering and a probabilistic relaxation-labeling algorithm, followed by a local gradient-based bottom-up merging procedure. Specially suited for region-based video coding, it strongly differs from other proposals in that it generates arbitrary shaped image regions with pixel accuracy at a low computational cost, while allowing full reconstruction of the segmentation at the decoder without the transmission of any region description information. Index Terms--Image segmentation, motion estimation and compensation, multiresolution, relaxation labeling, region merging.

The fabrication method of arrays of iron squares separated by submicrometric distances is presented. The magnetic elements are defined on a single crystal Fe(001) film by electron beam lithography followed by a ion beam etching process. The obtained Fe squares present smooth surfaces and homogeneous sizes over areas as large as 500 [micro]m x 500 [micro]m as analyzed by scanning electron and atomic force microscopies. The lateral size of the squares have been varied in the range 1-10 [micro]m in order to analyze the size dependence. The magnetic properties of the single crystalline squares have been studied by magnetooptical Kerr effect. The results reveal an important change in the hysteresis loops as the square dimensions are reduced below a threshold of 3 [micro]m. Index Terms--Electron beam lithography, iron, magnetooptical Kerr effect, single crystalline magnetic squares.

Ge1-x-ySixSny alloys have emerged as a new class of highly versatile IR semiconductors offering the potential for independent variation of band structure and lattice dimension, making them the first practical group IV ternary system fully compatible with Si CMOS processing. In this paper we develop and apply new synthetic protocols based on designer molecular hydrides of Si, Ge, and Sn to demonstrate this concept from a synthesis perspective. Variation of the Si/Sn ratio in the ternary leads to an entirely new family of semiconductors exhibiting tunable direct band gaps (Eo) ranging from 0.8 to 1 .2 eV at a fixed lattice constant identical to that of Ge, as required for the design of high-efficiency multijunction solar cells based on group IV/III-V hybrids. As a proof-of-concept demonstration, we fabricated lattice-matched Si(100)/Ge/SiGeSn/ InGaAs architectures on low-cost Si(100) substrates for the first time. These exhibit the required optical, structural, and thermal properties, thus representing a viable starting point en route to a complete four- junction photovoltaic device. In the context of Si-Ge-Sn optoelectronic applications, we show that Ge1-x-ySixSny alloys serve as higher-gap barrier layers for the formation of light emitting structures based on Ge1-ySny quantum wells grown on Si. [ABSTRACT FROM AUTHOR]