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We present data from detailed observations of CityWall, a large multi-touch display installed in a central location in Helsinki, Finland. During eight days of installation, 1199 persons interacted with the system in various social configurations. Videos of these encounters were examined qualitatively as well as quantitatively based on human coding of(More)
We describe and analyse in details the various factors that influence the convergence time of intradomain link state routing protocols. This convergence time reflects the time required by a network to react to the failure of a link or a router. To characterise the convergence process, we first use detailed measurements to determine the time required to(More)
For pt. 1 see ibid., vol. 13, no. 1, p.70-5 (2009). In this second part of a two-part article, the authors highlight the impact that different durations of IP packet loss have on the quality of experience for IP-based video streaming services. They describe the visual impairments that result from such packet losses and present the results of testing and(More)
Temporary outages in IP packet delivery can occur during network reconvergence events, and conventional error-control methods that end points use can't effectively deal with such extended blocks of packet loss. Service providers can employ a number of network technologies to minimize the IP packet loss during such outages, ultimately resulting in lossless(More)
BACKGROUND Th1/Th2 imbalance is hypothesized to up-regulate some diseases and down-regulate others. Compared to controls, multiple sclerosis (MS) (Th1-mediated) has been linked to a reduced risk of allergy and asthma (Th2-mediated), based on patient questionnaire studies and a review of asthma medication. AIM To investigate whether MS is associated with a(More)
Previous attempts to support spectators at large-scale events have concentrated separately on real-time event information, awareness cues, or media-sharing applications. CoMedia combines a group media space with event information and integrates reusable awareness elements throughout. In two field trials, one at a rally and the other at a music festival, we(More)
In this first part of a two-part article, the authors consider the network factors that impact the viewers' quality of experience (QoE) for IP-based video-streaming services such as IPTV. They describe the IP service-level requirements for a transported video service and explain MPEG encoding to help readers better understand the impact that packet loss has(More)
The differentiated services architecture (Diffserv) enables service providers to offer tighter, more comprehensive service-level agreements (SLAs) for IP service performance. One way it does this is by letting designers engineer IP backbone networks to assure that SLA parameters are met on a per-class basis. This review covers best practices for designing,(More)