| 1. |
- Bilbao, Stefan, et al.
(författare)
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Local Directional Source Modeling in Wave-based Acoustic Simulation
- 2019
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Ingår i: Proceedings of the International Congress on Acoustics. - 2226-7808 .- 2415-1599. - 9783939296157 ; 2019-September, s. 6377-6384
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Konferensbidrag (refereegranskat)abstract
- Time-domain wave-based simulation approaches such as the finite difference time domain (FDTD) method allow for a complete solution to the problem of virtual acoustics over the entire frequency range, in contrast with the methods of geometric acoustics which are valid in the limit of high frequencies. They also allow for flexible modelling of sources and receivers, due to the inherently local nature of the computation, and complete access to the computed acoustic field over an enclosure. In this paper, a method for the emulation of sources of arbitrary directivity is presented, framed directly as an inhomogeneous wave equation. The additional terms in the wave equation take the form of Dirac delta functions and their distributional derivatives, and collections of such terms may be associated directly with an expansion of source directivity in terms of spherical harmonics. The local nature of the model implies a locally-defined efficient computational approach for wave-based methods defined over a spatial grid. Numerical results are presented.
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| 2. |
- Pettersson, Ingrid M, 1979, et al.
(författare)
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Virtually the Same Experience? Learning from User Experience Evaluation of In-vehicle Systems in VR and in the Field
- 2019
-
Ingår i: DIS '19 Proceedings of the 2019 on Designing Interactive Systems Conference. - New York, NY, USA : ACM. - 9781450358507 ; , s. 463-473
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Konferensbidrag (refereegranskat)abstract
- In order to investigate how a VR study context influence participants’ User Experience responses of an interactive system an UX evaluation of the same in-vehicle systems was conducted in the field and in virtual reality. The virtual environment featured a virtual road scene and an interactive in-car environment, paired with a physical set-up containing a table-mounted steering wheel and a touch-sensitive panel. The VR system enabled a high estimation of presence and focus, however participants voiced less affect in the virtual setting and had difficulty in separating judgments of the VR experience from the UX of the in-vehicle systems. No significant differences in UX questionnaire data were identified between VR and the field, but there were correlations between rated presence in the VR system and UX ratings, especially for reported stimulation.Based on the lessons learned, a number of methodological and technological consequences are recommended in the paper, such as the need for more dynamic movement behaviour, improved resolution of graphics of the virtual vehicle and introducing the test leader as visually present in the virtual environment.
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| 3. |
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| 4. |
- Xiong, Kunli, 1987, et al.
(författare)
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Active control of plasmonic colors: emerging display technologies
- 2019
-
Ingår i: Reports on Progress in Physics. - : IOP Publishing. - 0034-4885 .- 1361-6633. ; 82:2
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Forskningsöversikt (refereegranskat)abstract
- In recent years there has been a growing interest in the use of plasmonic nanostructures for color generation, a technology that dates back to ancient times. Plasmonic structural colors have several attractive features but once the structures arc prepared the colors arc normally fixed. Lately, several concepts have emerged for actively tuning the colors, which opens up for many new potential applications, the most obvious being novel color displays. In this review we summarize recent progress in active control of plasmonic colors and evaluate them with respect to performance criteria for color displays. It is suggested that actively controlled plasmonic colors are generally less interesting for emissive displays but could be useful for new types of electrochromic devices relying on ambient light (electronic paper). Furthermore, there are several other potential applications such as images to be revealed on demand and colorimetric sensors.
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| 5. |
- Asplund, Simon, et al.
(författare)
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SWAY - designing for balance and posture awareness
- 2018
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Ingår i: TEI 2018 - Proceedings of the 12th International Conference on Tangible, Embedded, and Embodied Interaction. - New York : Association for Computing Machinery (ACM). - 9781450355681 ; , s. 470-475
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Konferensbidrag (refereegranskat)abstract
- This paper presents the SWAY prototype that encourages people to explore aspects around balance and posture in a playful way. The prototype senses small movements and shifts in posture using a Kinect sensor, and translates these movements to the tilting of a platform holding a set of marbles, and to haptic feedback in the form of vibrations. The prototype provides an interactive experience focusing on building body awareness with a particular focus on balance and posture. The design inquiry provided new insights with respect to reinforcement of bodily experiences and how different modalities affect the guiding of attention.
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| 6. |
- Bergström, Ilias, et al.
(författare)
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Sarka : Sonification and Somaesthetic Appreciation Design
- 2016
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Ingår i: MOCO'16. - New York, NY, USA : ASSOC COMPUTING MACHINERY. - 9781450343077
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Konferensbidrag (refereegranskat)abstract
- We often take for granted that we have immediate access to our perception and experience of and through our bodies. But inward listening is a demanding activity and thus not easy to learn to perform or design for. With the Sarka mat we want to support the ability to direct attention by providing sound feedback linked to the weight distribution and motion intensity of different parts of the body, and to provide an exemplar for how such design may be conducted. The process of Sarka's creation is informed by Somaesthetic Appreciation Design. We discuss how a sonic feedback signal can influence listeners, followed by how we, in this design, worked to navigate the complex design space presented to us. We detail the design process involved, and the very particular set of limitations which this interactive sonification presented.
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| 7. |
- Bresin, Roberto, 1963-, et al.
(författare)
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SOUND FOREST/LJUDSKOGEN: A LARGE-SCALE STRING-BASED INTERACTIVE MUSICAL INSTRUMENT
- 2016
-
Ingår i: Sound and Music Computing 2016. - : SMC Sound&Music Computing NETWORK. - 9783000537004 ; , s. 79-84
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Konferensbidrag (refereegranskat)abstract
- In this paper we present a string-based, interactive, largescale installation for a new museum dedicated to performing arts, Scenkonstmuseet, which will be inaugurated in 2017 in Stockholm, Sweden. The installation will occupy an entire room that measures 10x5 meters. We aim to create a digital musical instrument (DMI) that facilitates intuitive musical interaction, thereby enabling visitors to quickly start creating music either alone or together. The interface should be able to serve as a pedagogical tool; visitors should be able to learn about concepts related to music and music making by interacting with the DMI. Since the lifespan of the installation will be approximately five years, one main concern is to create an experience that will encourage visitors to return to the museum for continued instrument exploration. In other words, the DMI should be designed to facilitate long-term engagement. Finally, an important aspect in the design of the installation is that the DMI should be accessible and provide a rich experience for all museum visitors, regardless of age or abilities.
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| 8. |
- Bruckner, Stefan, et al.
(författare)
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A Model of Spatial Directness in Interactive Visualization
- 2018
-
Ingår i: IEEE Transactions on Visualization and Computer Graphics. - : Institute of Electrical and Electronics Engineers (IEEE). - 1077-2626 .- 1941-0506.
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Tidskriftsartikel (refereegranskat)abstract
- We discuss the concept of directness in the context of spatial interaction with visualization. In particular, we propose a model that allows practitioners to analyze and describe the spatial directness of interaction techniques, ultimately to be able to better understand interaction issues that may affect usability. To reach these goals, we distinguish between different types of directness. Each type of directness depends on a particular mapping between different spaces, for which we consider the data space, the visualization space, the output space, the user space, the manipulation space, and the interaction space. In addition to the introduction of the model itself, we also show how to apply it to several real-world interaction scenarios in visualization, and thus discuss the resulting types of spatial directness, without recommending either more direct or more indirect interaction techniques. In particular, we will demonstrate descriptive and evaluative usage of the proposed model, and also briefly discuss its generative usage.
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| 9. |
- Comber, Rob, Associate Professor, et al.
(författare)
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Towards Post-Interaction Computing : Addressing Immediacy, (un)Intentionality, Instability and Interaction Effects
- 2019
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Ingår i: Proceedings of the Halfway to the Future Symposium 2019. - New York, NY, USA : Association for Computing Machinery (ACM). - 9781450372039
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Konferensbidrag (refereegranskat)abstract
- The changes that have come about through the increased speed, ubiquity, and scale of computational systems require a reconceptualisation of how we think about and study the relationship between humans and computers. Driven by the increased production of data in interaction and the transfer of value from interaction to data, we argue that computing that fundamentally impacts human-computer relations is no longer happening only in interaction but also without and outside interaction. While recent arguments have highlighted interaction as a problematic concept for HCI — challenging what constitute users, use, the human, and the computer in interaction — we propose post-interaction computing as one means to conceptualise a fourth wave of HCI. We propose four concepts — immediacy, (un)intentionality, interaction effects, and instability — that can help us in identifying and slicing our objects of analysis in new ways that better match the challenges that HCI is now faced with.
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| 10. |
- Foka, Anna, et al.
(författare)
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Introduction to the DHQ Special Issue: Digital Technology in the Study of the Past
- 2018
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Ingår i: Digital Humanities Quarterly. - 1938-4122. ; 12:3
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Tidskriftsartikel (refereegranskat)abstract
- Digital technology is transforming the assemblage and dissemination of historical information. Museums, libraries, archives, and universities increasingly modify their digital research infrastructures in order to make data open and available. The imminent assessment and representation of historical data has admittedly challenged the boundaries of historical knowledge and generated new research questions. The process of reconstructing, visualizing and rendering historical data has equally developed together with technology. This is the case in both academic and heritage contexts and in less immediatedly obvious popular uses, such as the increasingly significant presence and use of history within videogames. Regardless of specific context, as this collection of articles shows, the process of digitally capturing and representing historical data is often analogous to and determined by the digital platform used.
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| 11. |
- Frid, Emma, et al.
(författare)
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Haptic feedback combined with movement sonification using a friction sound improves task performance in a virtual throwing task
- 2018
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Ingår i: Journal on Multimodal User Interfaces. - : Springer. - 1783-7677 .- 1783-8738. ; 13:4, s. 279-290
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we present a study on the effects of auditory- and haptic feedback in a virtual throwing task performed with a point-based haptic device. The main research objective was to investigate if and how task performance and perceived intuitiveness is affected when interactive sonification and/or haptic feedback is used to provide real-time feedback about a movement performed in a 3D virtual environment. Emphasis was put on task solving efficiency and subjective accounts of participants’ experiences of the multimodal interaction in different conditions. The experiment used a within-subjects design in which the participants solved the same task in different conditions: visual-only, visuohaptic, audiovisual and audiovisuohaptic. Two different sound models were implemented and compared. Significantly lower error rates were obtained in the audiovisuohaptic condition involving movement sonification based on a physical model of friction, compared to the visual-only condition. Moreover, a significant increase in perceived intuitiveness was observed for most conditions involving haptic and/or auditory feedback, compared to the visual-only condition. The main finding of this study is that multimodal feedback can not only improve perceived intuitiveness of an interface but that certain combinations of haptic feedback and movement sonification can also contribute with performance-enhancing properties. This highlights the importance of carefully designing feedback combinations for interactive applications.
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| 12. |
- Frid, Emma, et al.
(författare)
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Interactive sonification of a fluid dance movement : an exploratory study
- 2019
-
Ingår i: Journal on Multimodal User Interfaces. - : Springer. - 1783-7677 .- 1783-8738. ; 13:3, s. 181-189
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we present three different experiments designed to explore sound properties associated with fluid movement: (1) an experiment in which participants adjusted parameters of a sonification model developed for a fluid dance movement, (2) a vocal sketching experiment in which participants sketched sounds portraying fluid versus nonfluid movements, and (3) a workshop in which participants discussed and selected fluid versus nonfluid sounds. Consistent findings from the three experiments indicated that sounds expressing fluidity generally occupy a lower register and has less high frequency content, as well as a lower bandwidth, than sounds expressing nonfluidity. The ideal sound to express fluidity is continuous, calm, slow, pitched, reminiscent of wind, water or an acoustic musical instrument. The ideal sound to express nonfluidity is harsh, non-continuous, abrupt, dissonant, conceptually associated with metal or wood, unhuman and robotic. Findings presented in this paper can be used as design guidelines for future applications in which the movement property fluidity is to be conveyed through sonification.
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| 13. |
- Frid, Emma, et al.
(författare)
-
Sonification of fluidity -
An exploration of perceptual connotations of a particular movement feature
- 2016
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Ingår i: Proceedings of ISon 2016, 5th Interactive Sonification Workshop. - Bielefeld, Germany. ; , s. 11-17
-
Konferensbidrag (refereegranskat)abstract
- In this study we conducted two experiments in order to investigate potential strategies for sonification of the expressive movement quality “fluidity” in dance: one perceptual rating experiment (1) in which five different sound models were evaluated on their ability to express fluidity, and one interactive experiment (2) in which participants adjusted parameters for the most fluid sound model in (1) and performed vocal sketching to two video recordings of contemporary dance. Sounds generated in the fluid condition occupied a low register and had darker, more muffled, timbres compared to the non-fluid condition, in which sounds were characterized by a higher spectral centroid and contained more noise. These results were further supported by qualitative data from interviews. The participants conceptualized fluidity as a property related to water, pitched sounds, wind, and continuous flow; non-fluidity had connotations of friction, struggle and effort. The biggest conceptual distinction between fluidity and non-fluidity was the dichotomy of “nature” and “technology”, “natural” and “unnatural”, or even “human” and “unhuman”. We suggest that these distinct connotations should be taken into account in future research focusing on the fluidity quality and its corresponding sonification.
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| 14. |
- Frid, Emma, 1988-, et al.
(författare)
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Sound Forest - Evaluation of an Accessible Multisensory Music Installation
- 2019
-
Ingår i: Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems. - New York, NY, USA : ACM. - 9781450359702 ; , s. 1-12
-
Konferensbidrag (refereegranskat)abstract
- Sound Forest is a music installation consisting of a room with light-emitting interactive strings, vibrating platforms and speakers, situated at the Swedish Museum of Performing Arts. In this paper we present an exploratory study focusing on evaluation of Sound Forest based on picture cards and interviews. Since Sound Forest should be accessible for everyone, regardless age or abilities, we invited children, teens and adults with physical and intellectual disabilities to take part in the evaluation. The main contribution of this work lies in its fndings suggesting that multisensory platforms such as Sound Forest, providing whole-body vibrations, can be used to provide visitors of diferent ages and abilities with similar associations to musical experiences. Interviews also revealed positive responses to haptic feedback in this context. Participants of diferent ages used diferent strategies and bodily modes of interaction in Sound Forest, with activities ranging from running to synchronized music-making and collaborative play.
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| 15. |
- Graus, Mark, et al.
(författare)
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Theory-grounded user modeling for personalized HCI
- 2019
-
Ingår i: Personalized human-computer interaction. - Berlin : Walter de Gruyter. - 9783110552485 - 9783110552614
-
Bokkapitel (refereegranskat)abstract
- Personalized systems are systems that adapt themselves to meet the inferred needs of individual users. The majority of personalized systems mainly rely on data describing how users interacted with these systems. A common approach is to use historical data to predict users’ future needs, preferences, and behavior to subsequently adapt the system to cater to these predictions. However, this adaptation is often done without leveraging the theoretical understanding between behavior and user traits that can be used to characterize individual users or the relationship between user traits and needs that can be used to adapt the system. Adopting a more theoretical perspective can benefit personalization in two ways: (i) letting systems rely on theory can reduce the need for extensive data-driven analysis, and (ii) interpreting the outcomes of data-driven analysis (such as predictive models) from a theoretical perspective can expand our knowledge about users. However, incorporating theoretical knowledge in personalization brings forth a number of challenges. In this chapter, we review literature that taps into aspects of (i) psychological models from traditional psychological theory that can be used in personalization, (ii) relationships between psychological models and online behavior, (iii) automated inference of psychological models from data, and (iv) how to incorporate psychological models in personalized systems. Finally, we propose a step-by-step approach on how to design personalized systems that take users’ traits into account.
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| 16. |
- Hansen, Kjetil Falkenberg, Docent, 1972-, et al.
(författare)
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Student involvement in sound and music computing research : Current practices at KTH and KMH
- 2019
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Ingår i: Combined proceedings of the Nordic Sound and Music Computing Conference 2019 and the Interactive Sonification Workshop 2019. - Stockholm. ; , s. 36-42
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Konferensbidrag (refereegranskat)abstract
- To engage students in and beyond course activities has been a working practice both at KTH Sound and Music Computing group and at KMH Royal College of Music since many years. This paper collects experiences of involving students in research conducted within the two institutions. We describe how students attending our courses are given the possibility to be involved in our research activities, and we argue that their involvement both contributes to develop new research and benefits the students in the short and long term. Among the assignments, activities, and tasks we offer in our education programs are pilot experiments, prototype development, public exhibitions, performing, composing, data collection, analysis challenges, and bachelor and master thesis projects that lead to academic publications.
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| 17. |
- Khan, Muhammad Sikandar Lal, 1988-, et al.
(författare)
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Expressive multimedia : Bringing action to physical world by dancing-tablet
- 2015
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Ingår i: HCMC 2015 - Proceedings of the 2nd Workshop on Computational Models of Social Interactions. - New York, NY, USA : ACM Digital Library. - 9781450337472 ; , s. 9-14
-
Konferensbidrag (refereegranskat)abstract
- The design practice based on embodied interaction concept focuses on developing new user interfaces for computer devices that merge the digital content with the physical world. In this work we have proposed a novel embodied interaction based design in which the 'action' information of the digital content is presented in the physical world. More specifically, we have mapped the 'action' information of the video content from the digital world into the physical world. The motivating example presented in this paper is our novel dancing-tablet, in which a tablet-PC dances on the rhythm of the song, hence the 'action' information is not just confined into a 2D flat display but also expressed by it. This paper presents i) hardware design of our mechatronic dancingtablet platform, ii) software algorithm for musical feature extraction and iii) embodied computational model for mapping 'action' information of the musical expression to the mechatronic platform. Our user study shows that the overall perception of audio-video music is enhanced by our dancingtablet setup.
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| 18. |
- Knees, Peter, et al.
(författare)
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User Awareness in Music Recommender Systems
- 2019
-
Ingår i: Personalized human-computer interaction. - Berlin : Walter de Gruyter. - 9783110552485 - 9783110552614
-
Bokkapitel (refereegranskat)abstract
- Music recommender systems are a widely adopted application of personalized systems and interfaces.By tracking the listening activity of their users and building preference profiles, a user can be given recommendations based on the preference profiles of all users (collaborative filtering), characteristics of the music listened to (content-based methods), meta-data and relational data (knowledge-based methods; sometimes also considered content-based methods) or a mixture of these with other features (hybrid methods).In this chapter, we focus on the listener's aspects of music recommender systems.We discuss different factors influencing relevance for recommendation on both the listener's and the music's side and categorize existing work. In more detail, we then review aspects of (i) listener background in terms of individual, i.e., personality traits and demographic characteristics, and cultural features, i.e., societal and environmental characteristics, (ii) listener context, in particular modeling dynamic properties and situational listening behavior, and (iii) listener intention, in particular by studying music information behavior, i.e., how people seek, find, and use music information.This is followed by a discussion of user-centric evaluation strategies for music recommender systems. We conclude the chapter with a reflection on current barriers, by pointing out current and longer-term limitations of existing approaches and outlining strategies for overcoming these.
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| 19. |
- Kuenen, Stoffel, 1975-
(författare)
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Aesthetics of being together
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Design deals with matters of aesthetics. Historically, aesthetics in industrial design refers to the designed artifact: aesthetics of objects. When designed artifacts include digital technologies, aesthetics in design refers to what happens between people and artifacts as well: aesthetics of interaction. Now that these artifacts increasingly mediate our social lives, what aesthetics in design quite obviously also refers to, is what happens between people.This dissertation proposes an aesthetic of being together, as a necessary addition to current notions of aesthetics in interaction design practice, when it engages with digital systems that are part of people’s social life. It does not answer the question what Aesthetics is in general, instead it examines the work that particular notions of aesthetics do in interaction design practice.The practice based design research assembled in this dissertation starts from current notions of aesthetics in interaction design to explore the social experiences that mediated interactions between groups of people offer. What I found, through designing digital systems, is that current notions of aesthetics in interaction design are not conducive to addressing the kind of social experience people have with such systems. On the contrary, current notions actually inhibit interaction design to approach any experiences that cannot in the first place be conceived of as useful in terms of instrumental task performance. Yet, being social is hardly like performing a task or using other people in that sense.An aesthetic of being together is a proposition of a different fundament for interaction design practice. In addition to referring to properties of things and qualities of interacting with things, it refers to the kind of relations that come to expression between people interacting with each other with these things. Consequently, interaction design needs to resolve basic issues in what it considers and brings to expression, i.e. people’s relations with things and people at the same time. This requires (re-) considering what the designed thing is, what interaction is about and what the role of design is in bringing those to expression.My work contributes to the field of interaction design research an example of how, through practice, fundamental issues can be addressed. By orienting one set of concepts, ways of working and objectives into a different design situation, tensions built up that exposed foundational issues with that frame of reference, while pointing to the different fundaments needed to enable design practice to engage such situations.The results of the practical experimentation led to the articulation of a series of structural mechanisms of mediating systems. These mechanisms provide material handles for interaction designers on how experiences of being present with others take shape. They configure the relations of artifacts and people in different ways than current notions of aesthetics afford. This theoretical investigation is then synthesised in the form of a new logic of expression for interaction design practice: an aesthetic of being together.
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| 20. |
- Latupeirissa, Adrian Benigno, et al.
(författare)
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Sonic characteristics of robots in films
- 2019
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Ingår i: Proceedings of the 16th Sound and Music Computing Conference. - Malaga, Spain. ; , s. 1-6
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Konferensbidrag (refereegranskat)abstract
- Robots are increasingly becoming an integral part of our everyday life. Expectations on robots could be influenced by how robots are represented in science fiction films. We hypothesize that sonic interaction design for real-world robots may find inspiration from sound design of fictional robots. In this paper, we present an exploratory study focusing on sonic characteristics of robot sounds in films. We believe that findings from the current study could be of relevance for future robotic applications involving the communication of internal states through sounds, as well for sonification of expressive robot movements. Excerpts from five films were annotated and analysed using Long Time Average Spectrum (LTAS). As an overall observation, we found that robot sonic presence is highly related to the physical appearance of robots. Preliminary results show that most of the robots analysed in this study have “metallic” voice qualities, matching the material of their physical form. Characteristics of robot voices show significant differences compared to voices of human characters; fundamental frequency of robotic voices is either shifted to higher or lower values, and the voices span over a broader frequency band.
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| 21. |
- Mejtoft, Thomas, 1976-, et al.
(författare)
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Feedback in commercial educational applications : Guidelines and conceptual framework
- 2017
-
Ingår i: Proceedings of the European Conference on Cognitive Ergonomics 2017 (ECCE 2017). - New York, NY, USA : ACM Digital Library. - 9781450352567 ; , s. 113-120
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Konferensbidrag (refereegranskat)abstract
- In recent years, schools made large investments to increase the integration and use of contemporary technologies in teaching and learning.Today iPads and educational applications are growing in popularity and are commonly used. These technologies have a potential beneficial effect on the learning, but studies show that some applications have flaws that hinder these positive effects, for example regarding the feedback provided to the user. This study has determined a number of guidelines for effective feedback in a learning situation and has further shown how well these guidelines can be reached in an educational application today. The study shows that there are both advantages and disadvantages of feedback in an application compared to giving feedback in a more traditional learning situation. Many of the guidelines for effective feedback were found to be possible to reach in an application, and the greatest advantage found in applications is that they can provide feedback timely on each action taken by the pupils.
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| 22. |
- Mejtoft, Thomas, 1976-
(författare)
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Industry based projects and cases : A CDIO approach to students' learning
- 2015
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Ingår i: Proceedings of the 11th International CDIO Conference. - : Chengdu University of Information Technology.
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Konferensbidrag (refereegranskat)abstract
- Just as the media industry, media technology and interaction design are fast moving areas. Even though grounded in theoretical models, the problems that the students face after graduation are constantly changing and contemporary, which makes a CDIO approach to education important. This paper reports a case study concerning a project spanning two consecutive courses with the main objective to renew the digital news platforms of the media group VK Media. The project was carried out in 2013 with students from the five-year Master of Science program in Interaction Technology and Design at Umeå University, Sweden. The results illustrate how project-based learning and real case-based group projects can enhance both students learning and the internal process at the external industry partner. The results clearly show how that not only goals in the CDIO Syllabus 2.0 have been met during the project but also actual value has been created for the industry as the students’ design proposals have been implemented and launched publicly.
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| 23. |
- Mejtoft, Thomas, 1976-, et al.
(författare)
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Interaction design processes to facilitate changing business models in the newspaper industry : A case study of vk.se
- 2015
-
Ingår i: Proceedings of the 33rd Annual ACM Conference Extended Abstracts on Human Factors in Computing Systems. - New York, NY, USA : Association for Computing Machinery (ACM). - 9781450331463 ; , s. 2253-2258
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Konferensbidrag (refereegranskat)abstract
- This case study illustrates and analyzes the process of redesigning one of the largest news media site in Sweden during a cooperation between the Interaction Design Study Program at Umeå University and VK Media using a customer centric open approach. The results show that the design process used, both provided new insights for the industry and produced an appreciated website that facilitated the transition into a new revenue model using a paywall for digital content.
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| 24. |
- Mejtoft, Thomas, 1976-, et al.
(författare)
-
Use of Image Recognition of Social Media
- 2017
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Ingår i: ANZMAC 2017: Marketing for Impact. - Melbourne : RMIT University. ; , s. 271-278
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Konferensbidrag (refereegranskat)abstract
- Images are central to firms in their use of social media platforms as part of their marketing strategy. Images are a powerful online marketing tool as they allow for engagement and personalisation of marketing content for individual customers. However, images can be a double edge sword in the web 2.0 world, where consumers are able to post content to branded social media sites. This study evaluates the benefits of integrating image recognition into social media from the users perspective. The pilot study undertaken found the majority of the participants thought the possibilities presented for image recognition technology are useful, however they showed concern in relation to their privacy if this technology were to be in social media networks. The results also showed that prior familiarity with this technology does not have any significant impact in how social media users feel about having this technology in social media.
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| 25. |
- Paloranta, Jimmie, et al.
(författare)
-
Interaction with a large sized augmented string instrument intended for a public setting
- 2016
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Ingår i: Sound and Music Computing 2016. - Hamburg : Zentrum für Mikrotonale Musik und Multimediale Komposition (ZM4). - 9783000537004 ; , s. 388-395
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Konferensbidrag (refereegranskat)abstract
- In this paper we present a study of the interaction with a large sized string instrument intended for a large installation in a museum, with focus on encouraging creativity,learning, and providing engaging user experiences. In the study, nine participants were video recorded while interacting with the string on their own, followed by an interview focusing on their experiences, creativity, and the functionality of the string. In line with previous research, our results highlight the importance of designing for different levels of engagement (exploration, experimentation, challenge). However, results additionally show that these levels need to consider the users age and musical background as these profoundly affect the way the user plays with and experiences the string.
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| 26. |
- Samini, Ali, 1979-
(författare)
-
Perspective Correct Hand-held Augmented Reality for Improved Graphics and Interaction
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- With Augmented Reality, also termed AR, a view of the real world is augmented by superimposing computer-generated graphics, thereby enriching or enhancing the perception of the reality. Today, lots of applications benefit from AR in different areas, such as education, medicine, navigation, construction, gaming, and multiple other areas, using primarily head-mounted AR displays and AR on hand-held smart devices. Tablets and phones are highly suitable for AR, as they are equipped with high resolution screens, good cameras and powerful processing units, while being readily available to both industry and home use. They are used with video see-through AR, were the live view of the world is captured by a camera in real time and subsequently presented together with the computer graphics on the display.In this thesis I put forth our recent work on improving video see-through Augmented Reality graphics and interaction for hand-held devices by applying and utilizing user perspective. On the rendering side, we introduce a geometry-based user perspective rending method aiming to align the on screen content with the real view of the world visible around the screen. Furthermore, we introduce a device calibration system to compensate for misalignment between system parts. On the interaction side we introduce two wand-like direct 3D pose manipulation techniques based on this user perspective. We also modified a selection technique and introduced a new one suitable to be used with our introduced manipulation techniques. Finally, I present several formal user studies, evaluating the introduced techniques and comparing them with concurrent state-of-the-art alternatives.
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| 27. |
- Tewele, Mhretab Kidane, et al.
(författare)
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Supporting video conference communication using a vision-based human facial synthesis approach
- 2015
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Ingår i: Proceedings of IEEE <em>SAI Intelligent Systems Conference (IntelliSys), 2015</em>. - London : IEEE conference proceedings. - 9781467376068 ; , s. 807-812
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Konferensbidrag (refereegranskat)abstract
- Facial expressions plays an important role in human communication. In many cases where anonymity is a high priority, the identity of a person needs to be hidden or replaced by another one. Recent advancements in facial expression analysis technology have been used in order to duplicate facial human expressions with an avatar. However, a 3D avatar does not convey the same feeling as a real human face does. This paper documents an exploratory study investigating how vision-based facial analysis can be used to match someones facial expressions and head movements with pre-recorded video segments of another person. As a result of these efforts the identity of that person can be replaced with another person in real-time for videoconference supported communication. The proposed technical solutions have been implemented to support real-t
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| 28. |
- Thane, Gustav, 1982
(författare)
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Smide och Virtual Reality – Att uppleva dokumentationen
- 2019
-
Ingår i: Att synliggöra det osynliga - Om immateriellt kulturarv inom slöjd och hantverk, Sörmlands museum i Nyköping.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Virtual reality presenterar ofta miljöer som animerats men ibland är de filmade, ofta då med någon typ av 360 grader kamera där den som bär VR-glasögon inte kan gå runt det filmade. Fotogrammetri kan användas för att se verkliga fotograferade föremål men hur är det med rörlig bild? Gustav Thane har tillsammans med RISE Interactive utvecklat ett helt nytt koncept för att filma människor i aktivitet och spela upp dem som ett texturerat punktmoln i en VR-miljö.
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| 29. |
- Tkalcic, Marko, et al.
(författare)
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Theory-driven Recommendations : Modeling Hedonic and Eudaimonic Movie Preferences
- 2018
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Konferensbidrag (refereegranskat)abstract
- Most of the research in recommender systems focuses on data-driven approaches. In this paper we present our vision for complementing data-driven approaches with model-driven ones. We present a preliminary experimental set-up and we expose our research plan. In the experimental set-up we acquired eudaimonic characteristics of movies and user preferences. Furthermore, we performed a preliminary analysis of the acquired data.
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| 30. |
- Westin, Jonathan, 1980, et al.
(författare)
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A virtual diorama : Mapping archives in situ at places of cultural significance
- 2017
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Ingår i: Nordisk Museologi. - 1103-8152 .- 2002-0503. ; :2, s. 22-36
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Tidskriftsartikel (refereegranskat)abstract
- Using the wooden church of Södra Råda as a case study, this article concerns new applications of technology to contextualise and activate archive material in situ at places of cultural significance. Using a combination of augmented reality and virtual reality, we describe a process of turning historical photographs and two-dimensional reconstruction drawings into three-dimensional virtual models that can be lined up to a physical space. The leading questions for our investigation concern how archive material can be contextualised, and how the result may be made accessible in situ and contribute to place development. The result of this research suggests possibilities for using historical photographs to faithfully reconstruct lost historical spaces as three-dimensional surfaces that contextualise documentation and offer spatial information.
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| 31. |
- Adiels, Emil, 1989
(författare)
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Vapor Aymerich, Amat i Jover - Lluís Muncunill i Parellada
- 2018
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The Vapor Aymerich Amat I Jover is an old textile factory located in the town of Terrassa near Barcelona. It and was built between 1906 and 1909 and designed by architect Lluís Muncunill i Parellada. The structure is characterized by a modular system of wrought iron columns carrying brick arches supporting doubly curved brick vaults that are angled toward big windows that lets in natural light. It is often mentioned as a unique historically important masonry structure. This video is part of a collection of videos where masonry structures are documented and captured using motion pictures instead of stills to capture architectural qualities and experiences such as materiality, light and space. The project is funded by ARQ research fund.
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| 32. |
- Ahrens, Jens, 1978, et al.
(författare)
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Authentic Auralization of Acoustic Spaces Based on Spherical Microphone Array Recordings
- 2018
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Ingår i: Proceedings of the Institute of Acoustics. - 1478-6095. ; 40:3, s. 303-310
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Konferensbidrag (refereegranskat)abstract
- Many approaches for the capture and auralization of real acoustic spaces have been proposed over the past century. Limited spatial resolution on the capture side has typically been the factor that caused compromises in the achievable authenticity of the auralization. Recent advancements in the field of spherical microphone arrays provide new perspectives for both headphone-based and loudspeaker-based auralization. It has been shown that a bowling-ball-size spherical array of around 90 microphones allows for creating signals at the ears of the listener that are perceptually almost indistinguishable from the ear signals that arise in the original space. Head-tracked headphone auralization, i.e. playback that adapts to the instantaneous head orientation of the listener, has been shown to provide the best results. In the present contribution, we provide an overview of the technology and demonstrate the latest research advancements and remaining challenges.
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| 33. |
- Ahrens, Jens, 1978
(författare)
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Perceptual Evaluation of Binaural Auralization of Data Obtained From the Spatial Decomposition Method
- 2019
-
Ingår i: IEEE Workshop on Applications of Signal Processing to Audio and Acoustics. - 1931-1168 .- 1947-1629. ; , s. 65-69
-
Konferensbidrag (refereegranskat)abstract
- We present a perceptual evaluation of head-tracked binaural renderings of room impulse response data that were obtained from the spatial decomposition method. These data comprise an omnidirectional impulse response as well as instantaneous propagation directions of the sound field. The subjects in our experiment compared auralizations of these data according to the originally proposed method against direct auralizations of dummy head measurements of the exact same scenarios. We tested various parameters such as size of the microphone array, number of microphones, and HRTF grid-resolution. Our study shows that most parameter sets lead to a perception that is very similar to the dummy head data particlarly with respect to spaciousness. The remaining differences that are audible are considered small and relate primarily to timbre. This suggests that the equalization procedure that is part of the approach provides potential for improvement. Our results also show that the elevation of the propagation directions may be quantized coarsely without audible impairment.
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| 34. |
- Alexanderson, Simon, et al.
(författare)
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Real-time labeling of non-rigid motion capture marker sets
- 2017
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Ingår i: Computers & graphics. - : Elsevier. - 0097-8493 .- 1873-7684. ; 69:Supplement C, s. 59-67
-
Tidskriftsartikel (refereegranskat)abstract
- Passive optical motion capture is one of the predominant technologies for capturing high fidelity human motion, and is a workhorse in a large number of areas such as bio-mechanics, film and video games. While most state-of-the-art systems can automatically identify and track markers on the larger parts of the human body, the markers attached to the fingers and face provide unique challenges and usually require extensive manual cleanup. In this work we present a robust online method for identification and tracking of passive motion capture markers attached to non-rigid structures. The method is especially suited for large capture volumes and sparse marker sets. Once trained, our system can automatically initialize and track the markers, and the subject may exit and enter the capture volume at will. By using multiple assignment hypotheses and soft decisions, it can robustly recover from a difficult situation with many simultaneous occlusions and false observations (ghost markers). In three experiments, we evaluate the method for labeling a variety of marker configurations for finger and facial capture. We also compare the results with two of the most widely used motion capture platforms: Motion Analysis Cortex and Vicon Blade. The results show that our method is better at attaining correct marker labels and is especially beneficial for real-time applications.
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| 35. |
- Allan, Jon, 1972-
(författare)
-
Evaluation of Live Loudness Meters
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Discrepancies in loudness (i.e. sensation of audio intensity) has been of great concern within the broadcast community. For television broadcast, disparities in audio levels have been rated the number one cause to annoyance by the audience. Another problem area within the broadcast and music industry is the loudness war. The phenomenon is about the strive to produce audio content to be at least as loud or louder to any other audio content that it can easily be compared with. This mindset, when deciding for audio level treatment, inevitably leads to an increase in loudness over time, and also, as a technical consequence, a decrease of utilized dynamics. The effects of the loudness war is present in both terrestrial radio transmissions as well as in music production and in music distribution platforms.The two problems, discrepancies in loudness and the loudness war, both emanate from the same source; regulations of audio levels and the design of measurement gear have not been amended to cope with modern production techniques. At the time when the work on this thesis started, the ruling technical recommendations for audio level alignment were based on peak measurement. This measured entity has poor correspondence to loudness. To counter the above described problems, the European Broadcasting Union (EBU) and the International Telecommunication Union (ITU) has developed new recommendations for audio alignment, EBU R 128 and ITU-R BS.1770. The new definitions for loudness measurement constitutes simplified models on the human perception of audio intensity. When using the new recommendations in production, the problems have been shown to diminish.For an engineer in a live broadcast scenario, measurement equipment also need to be updated in real-time to illustrate a time-variant loudness of the signal. EBU and ITU also has regulated how this type of measurement gear should behave. EBU Tech 3341 and ITU-R BS.1771 define properties for live loudness meters. These recommendations has since the time of publication been implemented in measurement equipment from manufacturers and become available in production facilities.This thesis investigates the conceptions that have led up to the present recommendations for live loudness meters. It maps out the (at the time) present ways to evaluate the same. Emanating from this knowledge, a new methodology to evaluate loudness meters is proposed that combines qualities from former methods to achieve an alternative balance between ecological validity and control in the experiment design. The methodology includes a procedure to capture data from engineers’ actions and the resulting audio levels from simulated broadcast scenarios. The methodology also incorporates a way to process this type of data into different parameters to be more accessible for interpretation. It presents an approach to model the data, by the use of linear mixed models, to describe different effects in the parameters as the result of the meters’ characteristics. In addition, a review on publications that examine the engineers’ own requests for beneficial qualities in a loudness meter has been condensed and revised into a set of meter criteria that specifically is designed to be applied on the outcome of the mixed models. The outcome of the complete evaluation yields statements on meter quality that are different and complementary to formerly proposed methods for meter evaluation.The methodology has been applied in two different studies, which also are accounted for in the thesis. The conclusions from these studies has led to an increased understanding of how to design live loudness meters to be satisfactory tools to the engineer. Examples of findings are: the effect of the speed of the meter, as being controlled by one or several time constants, on the readability of the meter and the dispersion in output levels – some tested candidates, with higher speed than the present recommended ones, has been shown to be adequate as tools; the three-second integration time has been shown to generate a smaller dispersion in output levels than the 400 ms integration time; the effect of the gate in BS.1771 on the resulting output levels– the gate generally leading to an increase in output levels. The acquired knowledge may be used to improve the present recommendations for audio level alignment, from EBU and ITU.
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| 36. |
- Allison, Robert S., et al.
(författare)
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Perspectives on the definition of visually lossless quality for mobile and large format displays
- 2018
-
Ingår i: Journal of Electronic Imaging (JEI). - 1017-9909 .- 1560-229X. ; 27:5, s. 1-23
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Tidskriftsartikel (refereegranskat)abstract
- Advances in imaging and display engineering have given rise to new and improved image and videoapplications that aim to maximize visual quality under given resource constraints (e.g., power, bandwidth).Because the human visual system is an imperfect sensor, the images/videos can be represented in a mathematicallylossy fashion but with enough fidelity that the losses are visually imperceptible—commonly termed“visually lossless.” Although a great deal of research has focused on gaining a better understanding ofthe limits of human vision when viewing natural images/video, a universally or even largely accepted definitionof visually lossless remains elusive. Differences in testing methodologies, research objectives, and targetapplications have led to multiple ad-hoc definitions that are often difficult to compare to or otherwise employ inother settings. We present a compendium of technical experiments relating to both vision science and visualquality testing that together explore the research and business perspectives of visually lossless image quality,as well as review recent scientific advances. Together, the studies presented in this paper suggest that a singledefinition of visually lossless quality might not be appropriate; rather, a better goal would be to establish varyinglevels of visually lossless quality that can be quantified in terms of the testing paradigm.
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| 37. |
- Alonso-Fernandez, Fernando, 1978-, et al.
(författare)
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Very Low-Resolution Iris Recognition Via Eigen-Patch Super-Resolution and Matcher Fusion
- 2016
-
Ingår i: 2016 IEEE 8th International Conference on Biometrics Theory, Applications and Systems (BTAS). - Piscataway : IEEE. - 9781467397339 - 9781467397346
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Konferensbidrag (refereegranskat)abstract
- Current research in iris recognition is moving towards enabling more relaxed acquisition conditions. This has effects on the quality of acquired images, with low resolution being a predominant issue. Here, we evaluate a super-resolution algorithm used to reconstruct iris images based on Eigen-transformation of local image patches. Each patch is reconstructed separately, allowing better quality of enhanced images by preserving local information. Contrast enhancement is used to improve the reconstruction quality, while matcher fusion has been adopted to improve iris recognition performance. We validate the system using a database of 1,872 near-infrared iris images. The presented approach is superior to bilinear or bicubic interpolation, especially at lower resolutions, and the fusion of the two systems pushes the EER to below 5% for down-sampling factors up to a image size of only 13×13.
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| 38. |
- Anoosheh, Asha, et al.
(författare)
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Night-to-day image translation for retrieval-based localization
- 2019
-
Ingår i: Proceedings - IEEE International Conference on Robotics and Automation. - 1050-4729. ; 2019-May, s. 5958-5964
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Konferensbidrag (refereegranskat)abstract
- Visual localization is a key step in many robotics pipelines, allowing the robot to (approximately) determine its position and orientation in the world. An efficient and scalable approach to visual localization is to use image retrieval techniques. These approaches identify the image most similar to a query photo in a database of geo-tagged images and approximate the query's pose via the pose of the retrieved database image. However, image retrieval across drastically different illumination conditions, e.g. day and night, is still a problem with unsatisfactory results, even in this age of powerful neural models. This is due to a lack of a suitably diverse dataset with true correspondences to perform end-to-end learning. A recent class of neural models allows for realistic translation of images among visual domains with relatively little training data and, most importantly, without ground-truth pairings.In this paper, we explore the task of accurately localizing images captured from two traversals of the same area in both day and night. We propose ToDayGAN - a modified image-translation model to alter nighttime driving images to a more useful daytime representation. We then compare the daytime and translated night images to obtain a pose estimate for the night image using the known 6-DOF position of the closest day image. Our approach improves localization performance by over 250% compared the current state-of-the-art, in the context of standard metrics in multiple categories.
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| 39. |
- Arndt, Sebastian, et al.
(författare)
-
Review on using physiology in quality of experience
- 2016
-
Ingår i: Electronic Imaging. - : The Society for Imaging Science and Technology. - 9781510827943 ; , s. 197-205
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Konferensbidrag (refereegranskat)abstract
- In the area of Quality of Experience (QoE), one challenge is to design test methodologies in order to evaluate the perceived quality of multimedia content delivered through technical sys-tems. Traditionally, this evaluation is done using subjective opinion tests. However, sometimes it is difficult for observers to communicate the experienced quality through the given scale. Fur-thermore. those tests do not give insights into how the user is reacting on an internal physiological level. To overcome these issues, one approach is to use physiological measures, in order to derive a direct non-verbal response of the recipient. In this paper, we review studies that have been performed in the domain of QoE using physiological measures and we look into current activities in standardization bodies. We present challenges this research faces. and give an overview on what researchers should be aware of when they want to start working in this research area.
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| 40. |
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| 41. |
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| 42. |
- Balliu, Musard, et al.
(författare)
-
Securing IoT Apps
- 2019
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Ingår i: IEEE Security and Privacy. - : IEEE COMPUTER SOC. - 1540-7993 .- 1558-4046. ; 17:5, s. 22-29
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Tidskriftsartikel (refereegranskat)abstract
- Users increasingly rely on Internet of Things (IoT) apps to manage their digital lives through the overwhelming diversity of IoT services and devices. Are the IoT app platforms doing enough to protect the privacy and security of their users? By securing IoT apps, how can we help users reclaim control over their data?
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| 43. |
- Bohné, Ulrica, et al.
(författare)
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The EcoPanel: Designing for reflection on greener grocery shopping practices
- 2015
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Ingår i: PROCEEDINGS OF ENVIROINFO AND ICT FOR SUSTAINABILITY 2015. - : Atlantis Press. - 9789462520929 ; , s. 221-228
-
Konferensbidrag (refereegranskat)abstract
- While the purchases of organic food are increasing rapidly, it accounts for only a small fraction of the total consumption, and there is still a big gap between consumer values awareness and the actual consumption. This article explores how detailed personal feedback could help the households to gain insight and reflect on their consumption, the text presents the design process of developing a prototype, the EcoPanel, in collaboration with a major player on the food retail market. Based on the access to detailed tracking of purchase data, the aim of the design was to provide relevant feedback to facilitate for reflection on the user's own food choices. The design prototype is intended to serve as an instrument for insight and reflection and to bring unconscious aspects of grocery shopping to conscious awareness. Following a research through design approach, this article describes the interdependent steps in designing the EcoPanel and design decisions playing a role for users' critical reflection of their food choice practices. It discusses the intention of each module in providing insight. Finally, we discuss how a social practice perspective may be useful for identifying fruitful future research into the design for more sustainable grocery shopping practices
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| 44. |
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| 45. |
- Boshuijzen- van Burken, Christine, et al.
(författare)
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A normative analysis of the sharing economy
- 2015
-
Ingår i: Presented at EIASM Conference - Business Ethics, 5-6 November 2015, Brussels.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 46. |
- Boshuijzen- van Burken, Christine
(författare)
-
Beyond technological mediation : a normative practice approach
- 2016
-
Ingår i: Techné. - : Philosophy Documentation Center. - 1091-8264 .- 2691-5928. ; 20:3, s. 177-197
-
Tidskriftsartikel (refereegranskat)abstract
- Several philosophers of technology have argued that technology mediates human actions. For example, in the branch of post-phenomenology, authors such as Don Ihde and Peter-Paul Verbeek have described the mediating aspects of technology in terms of morality of technology (more prominent in Verbeek) as well as in the sense that technology changes our perception of ourselves and the world (more prominent in Ihde). In this article, different existing types of mediation are presented, critiqued, and enriched. The four types are illustrated by referring to military high-Tech environments with a focus on visual data and imaging technologies. These technologies can mediate actions (1) by inviting certain behavior, (2) through amplification and reduction, (3) through built-in norms, and (4) through interpretation. The four types of mediation mainly focus on the technology or technological artifact itself. What these approaches fail to grasp, however, is the specific user practices in which most technologies function. In this article, it is argued that to understand the mediating aspects of technology more fully, attention should be paid to the specific user context in which the technology functions. Therefore, an enriched understanding of the four types of mediation of technology is proposed by taking the lens of normative practices and analyzing the different types of mediation through this lens. The Kunduz Airstrike Incident, which took place in 2009 in Afghanistan, is a case in which a visual data sharing device called Rover played a prominent role. This case is used in this article to illustrate how technology mediates human actions in military practice.
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| 47. |
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| 48. |
- Bosse, Sebastian, et al.
(författare)
-
A common framework for the evaluation of psychophysiological visual quality assessment
- 2019
-
Ingår i: Quality and User Experience. - : Springer Science and Business Media LLC. - 2366-0139 .- 2366-0147. ; 4:3
-
Tidskriftsartikel (refereegranskat)abstract
- The assessment of perceived quality based on psychophysiological methods recently gained attraction as it potentially overcomes certain flaws of psychophysical approaches. Although studies report promising results, it is not possible to arrive at decisive and comparable conclusions that recommend the use of one or another method for a specific application or research question. The video quality expert group started a project on psychophysiological quality assessment to study these novel approaches and to develop a test plan that enables more systematic research. This test plan comprises of a specifically designed set of quality annotated video sequences, suggestions for psychophysiological methods to be studied in quality assessment, and recommendations for the documentation and publications of test results. The test plan is presented in this article.
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| 49. |
- Brunnstrom, Kjell, 1960-, et al.
(författare)
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Statistical quality of experience analysis: on planning the sample size and statistical significance testing
- 2018
-
Ingår i: Journal of Electronic Imaging (JEI). - SPIE/IS&T : IS&T - the Society for Imaging Science and Technology. - 1017-9909 .- 1560-229X. ; 27:5, s. 053013-1-053013-11
-
Tidskriftsartikel (refereegranskat)abstract
- This paper analyzes how an experimenter can balance errors in subjective video quality tests betweenthe statistical power of finding an effect if it is there and not claiming that an effect is there if the effect is not there,i.e., balancing Type I and Type II errors. The risk of committing Type I errors increases with the number ofcomparisons that are performed in statistical tests. We will show that when controlling for this and at thesame time keeping the power of the experiment at a reasonably high level, it is unlikely that the number oftest subjects that are normally used and recommended by the International Telecommunication Union (ITU),i.e., 15 is sufficient but the number used by the Video Quality Experts Group (VQEG), i.e., 24 is more likelyto be sufficient. Examples will also be given for the influence of Type I error on the statistical significance ofcomparing objective metrics by correlation. We also present a comparison between parametric and nonparametricstatistics. The comparison targets the question whether we would reach different conclusions on the statisticaldifference between the video quality ratings of different video clips in a subjective test, based on thecomparison between the student T-test and the Mann–Whitney U-test. We found that there was hardly a differencewhen few comparisons are compensated for, i.e., then almost the same conclusions are reached. Whenthe number of comparisons is increased, then larger and larger differences between the two methods arerevealed. In these cases, the parametric T-test gives clearly more significant cases, than the nonparametrictest, which makes it more important to investigate whether the assumptions are met for performing a certaintest.
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| 50. |
- Brunnström, Kjell, 1960-, et al.
(författare)
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Quality of experience of hand controller latency in a virtual reality simulator
- 2019
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Ingår i: IS and T International Symposium on Electronic Imaging Science and Technology. - Springfield, VA, United States : Society for Imaging Science and Technology.
-
Konferensbidrag (refereegranskat)abstract
- In this study, we investigate a VR simulator of a forestry crane used for loading logs onto a truck, mainly looking at Quality of Experience (QoE) aspects that may be relevant for task completion, but also whether there are any discomfort related symptoms experienced during task execution. A QoE test has been designed to capture both the general subjective experience of using the simulator and to study task performance. Moreover, a specific focus has been to study the effects of latency on the subjective experience, with regards to delays in the crane control interface. A formal subjective study has been performed where we have added controlled delays to the hand controller (joystick) signals. The added delays ranged from 0 ms to 800 ms. We found no significant effects of delays on the task performance on any scales up to 200 ms. A significant negative effect was found for 800 ms added delay. The Symptoms reported in the Simulator Sickness Questionnaire (SSQ) was significantly higher for all the symptom groups, but a majority of the participants reported only slight symptoms. Two out of thirty test persons stopped the test before finishing due to their symptoms.
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