- 13:00 Switching of Transmission Method of Sense of Force for Remote Haptic Control Systems
- Yutaka Ishibashi (Nagoya Institute of Technology,
Japan)
In this paper, we propose a scheme which dynamically
switches the transmission method (i.e., one-way or two-way)
of the sense of force according to network latency for
remote haptic control systems. The proposed scheme chooses the
two-way transmission of the sense of force when the network
latency between the master and slave terminals is small, and it
selects the one-way transmission of the sense of force when the
network latency between the terminals is large. We demonstrate
the effectiveness of the proposed scheme by subjective assessment.
Assessment results show that there exists the optimum switching
time depending on the work contents.
- 13:30 Switching Scheme of Group Synchronization Control in Multipoint Communications
- Kazuki Hosoya (Nagoya Institute of Technology,
Japan); Yutaka Ishibashi (Nagoya Institute of
Technology, Japan); Shinji Sugawara (Nagoya Institute
of Technology, Japan); Kostas Psannis (University of
Macedonia, Greece)
In this paper, we propose a scheme which switches
group (or inter-destination) synchronization control among three
states dynamically according to work contents in multipoint
communications with voice and video. In one state, group
synchronization control is not exerted. In another state, the
conventional group synchronization control is performed. In
the other state, the group synchronization control considering
difference of conversation roles is carried out. The proposed
scheme can also switch conversation roles. By examining the
timing from the generation of voice and video until the output,
we demonstrate that proposed scheme can switch among the
three states correctly, and the scheme can switch conversation
roles adequately.
- 14:00 Quality-of-Experience Beyond MOS: Experiences with a Holistic User Test Methodology for Interactive Video Services
- Sebastian Egger (Telecommunications Research Center Vienna (ftw.), Austria); Peter Reichl (Telecommunications Research Center Vienna (ftw.), Austria); Michal Ries (Vienna University of Technology, Austria)
Interactive video services, like video telephony, social
TV or on-line gaming, are about to become a significant part
of the service portfolio for telecommunication service providers.
As the future commercial success of these services will depend essentially
on their end-to-end quality as perceived by the end user,
appropriate Quality-of-Experience (QoE) measurement methods
are of paramount importance. The aim of this paper is to provide
an application-oriented re-evaluation of actual QoE metrics for
these services and to design a test methodology for evaluating
user perceived experience which goes beyond standard Mean
Opinion Score (MOS) metrics. To this end, we describe a specific
test scenario designed for assessing the currently recommended
question sets from two ITU recommendations. We determine
the goodness of fit of these question sets to the user perceived
quality dimension. Altogether, the resulting reduced set of items
(questions) provides a significant step towards a more realistic
methodology for assessing audio-visual quality perception.
- 14:30 Quality of Experience-Related Differential Equations and Provisioning-Delivery Hysteresis
- Markus Fiedler (Blekinge Institute of Technology, Sweden); Tobias Hossfeld (University of Wuerzburg, Germany)
Churn of revenue-generating and dissatisfied users has become a major point of concern for service providers and network operators. As services rely on interconnecting networks, service performance and thus user satisfaction depend on network performance. Consequently, it is of outmost importance to understand the relationships between user perception, captured by quantitative Quality of Experience (QoE) parameters, and network performance, described by Quality of Service (QoS) parameters. This paper provides insights into fundamental relationships between QoE and QoS, formulated as partial differential equations
describing changes in QoE with respect to specific QoS parameters. A set of illustrating examples is given. Furthermore, the different impacts of provisioning and degree of success or failure of delivery on QoE are discussed,
leading to QoE provisioning-delivery hysteresis. This hysteresis provides a striking motivation for employing elastic adaptation mechanisms to available resources instead of suffering from uncontrolled data loss.