Cognitieve Ergonomie

Cognitieve Ergonomie: het snijvlak van gedrag, cognitie, techniek en virtuele omgevinge

Enhancing the Quality of Service of mobile video technology by increasing multimodal synergy

Bandwidth is still a limiting factor for the Quality of Service (QoS) of mobile communication applications. In particular, for Voice over IP the QoS is not yet as good as for common, well-engineered, public-switched telephone networks. Multisensory communication has been identified as a possibility to moderate this limitation. One of the strengths of mobile video technology lies in its combination of visual and auditory modalities. However, one of the most salient features of mobile video applications is its small screen size. To test the potential of multimodal synergy for mobile devices, we assessed to what extent small screens affect multimodal synergy. This potential was assessed in an experiment with 54 participants, who conducted a standardised video-listening test for three talking-heads videos with a signal-tonoise ratio of –9 dB. The videos were presented on three different screen sizes, whilst keeping the video and auditory signals equal. Compared to a ground truth based on 359 participants, intelligibility was found to be significantly higher when using a large screen than when using a small screen. This indicates that mobile video technology has the potential for a significant multimodal synergy to which screen size is a substantial constraint. To optimally benefit from their multimodal potential, we offer suggestions on how to increase the effective screen size for small screen (e.g. mobile) devices and applications through elaborating the most relevant (visual) features. We conclude that knowledge about human sensory processing can alleviate the identified constraint and maximise the potential QoS of mobile video technology

Exploring workload and attention measurements with uLog mouse data

User–system interactions (e.g., mouse clicks and movements) can be logged with the uLog computer program. A Web-based study with 20 participants was conducted to investigate the feasibility of using uLog data as an indicator of workload and attention. Eye fixation, heart rate variability (HRV), and skin conductance were used to unveil users’ workload and attention and, hence, to validate uLog data as indicators of these. Results on one of the Tasks did indeed show correlations between uLog data and HRV. This is a promising first step toward the validation of uLog mouse data as indicators of workload and attention

Mobile Screen Size Limits Multimodal Synergy

Available bandwidth is still a limiting factor for mobile communication applications. Multisensory communication has already been identified as an possibility to moderate this limitation. One of the strengths of mobile communication lies in its combination of visual and auditory modalities. However, one of the most salient features of mobile devices have are their small screen size. This paper explores how the potential for multimodal synergy relates to the small screen size. In an experiment with 54 participants, the intelligibility was tested using a standardized video-listening test. The videos had a signal-to-noise ratio of -9dB and were presented on three different screen sizes, whilst keeping the video and auditory signals equal. Intelligibility was found to be significantly higher when using a large screen in comparison to using either of both smaller screens. We conclude that multisensory synergy is key to mobile applications, yet that screen size is a substantial constraint to this synergy. We argue that knowledge about human sensory processing can alleviate this constraint and maximize the potential quality of service of mobile video technology

Enhancing the Quality of Service of mobile video technology by increasing multimodal synergy

Bandwidth is still a limiting factor for the Quality of Service (QoS) of mobile communication applications. In particular, for Voice over IP the QoS is not yet as good as for common, well-engineered, public-switched telephone networks. Multisensory communication has been identified as a possibility to moderate this limitation. One of the strengths of mobile video technology lies in its combination of visual and auditory modalities. However, one of the most salient features of mobile video applications is its small screen size. To test the potential of multimodal synergy for mobile devices, we assessed to what extent small screens affect multimodal synergy. This potential was assessed in an experiment with 54 participants, who conducted a standardised video-listening test for three talking-heads videos with a signal-tonoise ratio of –9 dB. The videos were presented on three different screen sizes, whilst keeping the video and auditory signals equal. Compared to a ground truth based on 359 participants, intelligibility was found to be significantly higher when using a large screen than when using a small screen. This indicates that mobile video technology has the potential for a significant multimodal synergy to which screen size is a substantial constraint. To optimally benefit from their multimodal potential, we offer suggestions on how to increase the effective screen size for small screen (e.g. mobile) devices and applications through elaborating the most relevant (visual) features. We conclude that knowledge about human sensory processing can alleviate the identified constraint and maximise the potential QoS of mobile video technology

On the use of video prototyping in designing ambient user experiences

We discuss a case study where this technique was used in the design of an ambient intelligence system, highlighting how it impacted the design process both in positive and negative ways. This contextualized account complements related comparative studies that have been conducted outside the context of a design project, and have focused on methodological aspects of video prototyping. We conclude that designers need to be aware of how video as a persuasive medium obfuscates implementation and usability issues, and video prototype production should communicate explicitly the scope of the design issues that it addresses and those it does not.</p

Designing for Joint Human-Automation Cognition Through a Shared Representation of 4D Trajectory Management

The current evolution of the ATM system, led by the SESAR programme in Europe and the NextGen programme in the US, is foreseen to bring a paradigm shift to the work domain of the air traffic controller. A focal point is the introduction of the 4D (space and time) trajectory as a means for strategic management rather than the current –hands on– method of control. In both programmes a central role is foreseen for the human operator, aided by higher levels of automation and advanced decision support tools. However, many other complex socio-technical domains have shown that the transition to higher levels of automation often introduces new problems, problems that are harder to resolve than the ones intended to solve in the first place. This paper presents one approach to the design of a shared representation for 4D trajectory management. The ultimate goal is to design a shared representation which forms the basis for both the design of the humanmachine interfaces and the rationale that guides the automation. It is expected that such a shared representation will greatly benefit the joint cognition of humans and automated agents in ATM and will mitigate breakdowns in coordination by design. A preliminary version of a joint cognitive representation for 4D trajectory management has been developed and is introduced in this paper. Future work will focus on the further development and refinement of shared representations by means of human-in-the-loop experiments

On the use of video prototyping in designing ambient user experiences

We discuss a case study where this technique was used in the design of an ambient intelligence system, highlighting how it impacted the design process both in positive and negative ways. This contextualized account complements related comparative studies that have been conducted outside the context of a design project, and have focused on methodological aspects of video prototyping. We conclude that designers need to be aware of how video as a persuasive medium obfuscates implementation and usability issues, and video prototype production should communicate explicitly the scope of the design issues that it addresses and those it does not