User evaluation outside the lab: the trial of Físchlár-News

A user study of Físchlár-News system was conducted in Spring 2004 with 16 users, each user using the system for a 1-month period. Físchlár-News is an experimental online news archive that incorporates various automatic content-based video indexing techniques and a news story recommender algorithm to process and index the daily 9 o’clock broadcast news from TV and allows its users to browse, search, be recommended, and play news stories on a conventional web browser. Pre and post-trial questionnaires, interaction logging and incident diary methods collected both qualitative and quantitative usage data during the trial period. While the details of the findings from this evaluation is reported elsewhere, in this paper we report the details of the methodology taken and our experience of conducting this evaluation

Aggregating Content and Network Information to Curate Twitter User Lists

Twitter introduced user lists in late 2009, allowing users to be grouped according to meaningful topics or themes. Lists have since been adopted by media outlets as a means of organising content around news stories. Thus the curation of these lists is important - they should contain the key information gatekeepers and present a balanced perspective on a story. Here we address this list curation process from a recommender systems perspective. We propose a variety of criteria for generating user list recommendations, based on content analysis, network analysis, and the "crowdsourcing" of existing user lists. We demonstrate that these types of criteria are often only successful for datasets with certain characteristics. To resolve this issue, we propose the aggregation of these different "views" of a news story on Twitter to produce more accurate user recommendations to support the curation process

Applied constant gain amplification in circulating loop experiments

The reconfiguration of channel or wavelength routes in optically transparent mesh networks can lead to deviations in channel power that may impact transmission performance. A new experimental approach, applied constant gain, is used to maintain constant gain in a circulating loop enabling the study of gain error effects on long-haul transmission under reconfigured channel loading. Using this technique we examine a number of channel configurations and system tuning operations for both full-span dispersion-compensated and optimized dispersion-managed systems. For each system design, large power divergence was observed with a maximum of 15 dB at 2240 km, when switching was implemented without additional system tuning. For a bit error rate of 10-3, the maximum number of loop circulations was reduced by up to 33%

Dynamic circulating-loop methods for transmission experiments in optically transparent networks

Recent experiments incorporating multiple fast switching elements and automated system configuration in a circulating loop apparatus have enabled the study of aspects of long-haul WDM transmission unique to optically transparent networks. Techniques include per-span switching to measure the performance limits due to dispersion compensation granularity and mesh network walk-off, and applied constant-gain amplification to evaluate wavelength reconfiguration penalties

Mobile content enrichment

Delivering an effective mobile search service is challenging for many reasons. Certainly small-screen mobile handsets with limited text input capabilities do not make ideal search devices. In addition, the brevity of Mobile Internet content hampers effective indexing and limits retrieval opportunities. In this paper we focus on this indexing issue and describe an approach that leverages Web search engines as a source of content enrichment. We present an evaluation using a mobile news service that demonstrated significant improvements in search performance compared to a standard benchmark sys-tem

Use of the Físchlár video library system

Físchlár is a shared video retrieval system that lets users record, browse and watch television programmes using their web browser. In Físchlár, the programmes users can watch and record are organised by channel, by theme and by personal recommendation as provided by the ChangingWorlds’ ClixSmart personalisation engine. Our initial results from user trials illustrate the usage of each of these features

Classifying public display systems: an input/output channel perspective

Public display screens are relatively recent additions to our world, and while they may be as simple as a large screen with minimal input/output features, more recent developments have introduced much richer interaction possibilities supporting a variety of interaction styles. In this paper we propose a framework for classifying public display systems with a view to better understanding how they differ in terms of their interaction channels and how future installations are likely to evolve. This framework is explored through 15 existing public display systems which use mobile phones for interaction in the display space

Improving the quality of the personalized electronic program guide

As Digital TV subscribers are offered more and more channels, it is becoming increasingly difficult for them to locate the right programme information at the right time. The personalized Electronic Programme Guide (pEPG) is one solution to this problem; it leverages artificial intelligence and user profiling techniques to learn about the viewing preferences of individual users in order to compile personalized viewing guides that fit their individual preferences. Very often the limited availability of profiling information is a key limiting factor in such personalized recommender systems. For example, it is well known that collaborative filtering approaches suffer significantly from the sparsity problem, which exists because the expected item-overlap between profiles is usually very low. In this article we address the sparsity problem in the Digital TV domain. We propose the use of data mining techniques as a way of supplementing meagre ratings-based profile knowledge with additional item-similarity knowledge that can be automatically discovered by mining user profiles. We argue that this new similarity knowledge can significantly enhance the performance of a recommender system in even the sparsest of profile spaces. Moreover, we provide an extensive evaluation of our approach using two large-scale, state-of-the-art online systems—PTVPlus, a personalized TV listings portal and Físchlár, an online digital video library system

Optical IP switching a solution to dynamic lightpath establishment in disaggregated network architectures

The landscape of the telecommunications environment is constantly evolving; in terms of architecture and increasing data-rate. Ensuring that routing decisions are taken at the lowest possible layer offers the possibility of greatest data throughput. We propose using wavelengths in a DWDM scheme as dedicated channels that bypass the routing lookup in a router. The future trend of telecommunications industry is, however, toward larger numbers of interlinked competing operator networks. This in turn means there is a lack of a unified control plane to allow current networks to dynamically provision optical paths. This paper will report on the concept of optical IP switching. This concept seeks to address optical control plane issues in disaggregated networks while providing a means to dynamically provision optical paths to cater for large data flows