143 research outputs found

    An Augmented Reality system for the treatment of phobia to small animals viewed via an optical see-through HMD. Comparison with a similar system viewed via a video see-through

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    This article presents an optical see-through (OST) Augmented Reality system for the treatment of phobia to small animals. The technical characteristics of the OST system are described, and a comparative study of the sense of presence and anxiety in a nonphobic population (24 participants) using the OST and an equivalent video see-though (VST) system is presented. The results indicate that if all participants are analyzed, the VST system induces greater sense of presence than the OST system. If the participants who had more fear are analyzed, the two systems induce a similar sense of presence. For the anxiety level, the two systems provoke similar and significant anxiety during the experiment. © Taylor & Francis Group, LLC.Juan, M.; Calatrava, J. (2011). An Augmented Reality system for the treatment of phobia to small animals viewed via an optical see-through HMD. Comparison with a similar system viewed via a video see-through. International Journal of Human-Computer Interaction. 27(5):436-449. doi:10.1080/10447318.2011.552059S436449275Azuma, R. and Bishop, G. Improving static and dynamic registration in an optical see-through HMD. Proceedings of 21st Annual Conference on Computer Graphics and Interactive techniques (SIGGRAPH'94). pp.197–204.Bimber, O., & Raskar, R. (2005). Spatial Augmented Reality. doi:10.1201/b10624Botella, C., Quero, S., Banos, R. M., Garcia-Palacios, A., Breton-Lopez, J., Alcaniz, M., & Fabregat, S. (2008). Telepsychology and Self-Help: The Treatment of Phobias Using the Internet. CyberPsychology & Behavior, 11(6), 659-664. doi:10.1089/cpb.2008.0012Botella, C. M., Juan, M. C., Baños, R. M., Alcañiz, M., Guillén, V., & Rey, B. (2005). Mixing Realities? An Application of Augmented Reality for the Treatment of Cockroach Phobia. CyberPsychology & Behavior, 8(2), 162-171. doi:10.1089/cpb.2005.8.162Carlin, A. S., Hoffman, H. G., & Weghorst, S. (1997). Virtual reality and tactile augmentation in the treatment of spider phobia: a case report. Behaviour Research and Therapy, 35(2), 153-158. doi:10.1016/s0005-7967(96)00085-xGarcia-Palacios, A., Hoffman, H., Carlin, A., Furness, T. ., & Botella, C. (2002). Virtual reality in the treatment of spider phobia: a controlled study. Behaviour Research and Therapy, 40(9), 983-993. doi:10.1016/s0005-7967(01)00068-7Genc, Y., Tuceryan, M., & Navab, N. (s. f.). Practical solutions for calibration of optical see-through devices. Proceedings. International Symposium on Mixed and Augmented Reality. doi:10.1109/ismar.2002.1115086Hoffman, H. G., Garcia-Palacios, A., Carlin, A., Furness III, T. A., & Botella-Arbona, C. (2003). Interfaces That Heal: Coupling Real and Virtual Objects to Treat Spider Phobia. International Journal of Human-Computer Interaction, 16(2), 283-300. doi:10.1207/s15327590ijhc1602_08Juan, M. C., Alcaniz, M., Monserrat, C., Botella, C., Banos, R. M., & Guerrero, B. (2005). Using Augmented Reality to Treat Phobias. IEEE Computer Graphics and Applications, 25(6), 31-37. doi:10.1109/mcg.2005.143Juan, M. C., Baños, R., Botella, C., Pérez, D., Alcaníiz, M., & Monserrat, C. (2006). An Augmented Reality System for the Treatment of Acrophobia: The Sense of Presence Using Immersive Photography. Presence: Teleoperators and Virtual Environments, 15(4), 393-402. doi:10.1162/pres.15.4.393Kato, H., & Billinghurst, M. (s. f.). Marker tracking and HMD calibration for a video-based augmented reality conferencing system. Proceedings 2nd IEEE and ACM International Workshop on Augmented Reality (IWAR’99). doi:10.1109/iwar.1999.803809Nash, E. B., Edwards, G. W., Thompson, J. A., & Barfield, W. (2000). A Review of Presence and Performance in Virtual Environments. International Journal of Human-Computer Interaction, 12(1), 1-41. doi:10.1207/s15327590ijhc1201_1Owen, C. B., Ji Zhou, Tang, A., & Fan Xiao. (s. f.). Display-Relative Calibration for Optical See-Through Head-Mounted Displays. Third IEEE and ACM International Symposium on Mixed and Augmented Reality. doi:10.1109/ismar.2004.28Özbek, C., Giesler, B. and Dillmann, R. Jedi training: Playful evaluation of head-mounted augmented reality display systems. SPIE Conference Medical Imaging. Vol. 5291, pp.454–463.Renaud, P., Bouchard, S., & Proulx, R. (2002). Behavioral avoidance dynamics in the presence of a virtual spider. IEEE Transactions on Information Technology in Biomedicine, 6(3), 235-243. doi:10.1109/titb.2002.802381Schwald, B. and Laval, B. An Augmented Reality system for training and assistance to maintenance in the industrial context. International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision. pp.425–432.Slater, M., Usoh, M., & Steed, A. (1994). Depth of Presence in Virtual Environments. Presence: Teleoperators and Virtual Environments, 3(2), 130-144. doi:10.1162/pres.1994.3.2.130Szymanski, J., & O’Donohue, W. (1995). Fear of Spiders Questionnaire. Journal of Behavior Therapy and Experimental Psychiatry, 26(1), 31-34. doi:10.1016/0005-7916(94)00072-

    Superimposing Dynamic Range

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    We present a simple and cost-efficient way of extending contrast, perceived tonal resolution, and the color space of static hardcopy images, beyond the capabilities of hardcopy devices or low-dynamic range displays alone. A calibrated projector-camera system is applied for automatic registration, scanning and superimposition of hardcopies. We explain how high-dynamic range content can be split for linear devices with different capabilities, how luminance quantization can be optimized with respect to the non-linear response of the human visual system as well as for the discrete nature of the applied modulation devices; and how inverse tone-mapping can be adapted in case only untreated hardcopies and softcopies (such as regular photographs) are available. We believe that our approach has the potential to complement hardcopy-based technologies, such as X-ray prints for filmless imaging, in domains that operate with high quality static image content, like radiology and other medical fields, or astronomy

    Developing serious games for cultural heritage: a state-of-the-art review

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    Although the widespread use of gaming for leisure purposes has been well documented, the use of games to support cultural heritage purposes, such as historical teaching and learning, or for enhancing museum visits, has been less well considered. The state-of-the-art in serious game technology is identical to that of the state-of-the-art in entertainment games technology. As a result, the field of serious heritage games concerns itself with recent advances in computer games, real-time computer graphics, virtual and augmented reality and artificial intelligence. On the other hand, the main strengths of serious gaming applications may be generalised as being in the areas of communication, visual expression of information, collaboration mechanisms, interactivity and entertainment. In this report, we will focus on the state-of-the-art with respect to the theories, methods and technologies used in serious heritage games. We provide an overview of existing literature of relevance to the domain, discuss the strengths and weaknesses of the described methods and point out unsolved problems and challenges. In addition, several case studies illustrating the application of methods and technologies used in cultural heritage are presented

    KIR Polymorphisms Modulate Peptide-Dependent Binding to an MHC Class I Ligand with a Bw6 Motif

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    Molecular interactions between killer immunoglobulin-like receptors (KIRs) and their MHC class I ligands play a central role in the regulation of natural killer (NK) cell responses to viral pathogens and tumors. Here we identify Mamu-A1*00201 (Mamu-A*02), a common MHC class I molecule in the rhesus macaque with a canonical Bw6 motif, as a ligand for Mamu-KIR3DL05. Mamu-A1*00201 tetramers folded with certain SIV peptides, but not others, directly stained primary NK cells and Jurkat cells expressing multiple allotypes of Mamu-KIR3DL05. Differences in binding avidity were associated with polymorphisms in the D0 and D1 domains of Mamu-KIR3DL05, whereas differences in peptide-selectivity mapped to the D1 domain. The reciprocal exchange of the third predicted MHC class I-contact loop of the D1 domain switched the specificity of two Mamu-KIR3DL05 allotypes for different Mamu-A1*00201-peptide complexes. Consistent with the function of an inhibitory KIR, incubation of lymphocytes from Mamu-KIR3DL05+ macaques with target cells expressing Mamu-A1*00201 suppressed the degranulation of tetramer-positive NK cells. These observations reveal a previously unappreciated role for D1 polymorphisms in determining the selectivity of KIRs for MHC class I-bound peptides, and identify the first functional KIR-MHC class I interaction in the rhesus macaque. The modulation of KIR-MHC class I interactions by viral peptides has important implications to pathogenesis, since it suggests that the immunodeficiency viruses, and potentially other types of viruses and tumors, may acquire changes in epitopes that increase the affinity of certain MHC class I ligands for inhibitory KIRs to prevent the activation of specific NK cell subsets

    Dynamics of Envelope Evolution in Clade C SHIV-Infected Pig-Tailed Macaques during Disease Progression Analyzed by Ultra-Deep Pyrosequencing

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    Understanding the evolution of the human immunodeficiency virus type 1 (HIV-1) envelope during disease progression can provide tremendous insights for vaccine development, and simian-human immunodeficiency virus (SHIV) infection of non-human primate provides an ideal platform for such studies. A newly developed clade C SHIV, SHIV-1157ipd3N4, which was able to infect rhesus macaques, closely resembled primary HIV-1 in transmission and pathogenesis, was used to infect several pig-tailed macaques. One of the infected animals subsequently progressed to AIDS, whereas one remained a non-progressor. The viral envelope evolution in the infected animals during disease progression was analyzed by a bioinformatics approach using ultra-deep pyrosequencing. Our results showed substantial envelope variations emerging in the progressor animal after the onset of AIDS. These envelope variations impacted the length of the variable loops and charges of different envelope regions. Additionally, multiple mutations were located at the CD4 and CCR5 binding sites, potentially affecting receptor binding affinity, viral fitness and they might be selected at late stages of disease. More importantly, these envelope mutations are not random since they had repeatedly been observed in a rhesus macaque and a human infant infected by either SHIV or HIV-1, respectively, carrying the parental envelope of the infectious molecular clone SHIV-1157ipd3N4. Moreover, similar mutations were also observed from other studies on different clades of envelopes regardless of the host species. These recurring mutations in different envelopes suggest that there may be a common evolutionary pattern and selection pathway for the HIV-1 envelope during disease progression

    Geographic Visualization in Archaeology

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    Archaeologists are often considered frontrunners in employing spatial approaches within the social sciences and humanities, including geospatial technologies such as geographic information systems (GIS) that are now routinely used in archaeology. Since the late 1980s, GIS has mainly been used to support data collection and management as well as spatial analysis and modeling. While fruitful, these efforts have arguably neglected the potential contribution of advanced visualization methods to the generation of broader archaeological knowledge. This paper reviews the use of GIS in archaeology from a geographic visualization (geovisual) perspective and examines how these methods can broaden the scope of archaeological research in an era of more user-friendly cyber-infrastructures. Like most computational databases, GIS do not easily support temporal data. This limitation is particularly problematic in archaeology because processes and events are best understood in space and time. To deal with such shortcomings in existing tools, archaeologists often end up having to reduce the diversity and complexity of archaeological phenomena. Recent developments in geographic visualization begin to address some of these issues, and are pertinent in the globalized world as archaeologists amass vast new bodies of geo-referenced information and work towards integrating them with traditional archaeological data. Greater effort in developing geovisualization and geovisual analytics appropriate for archaeological data can create opportunities to visualize, navigate and assess different sources of information within the larger archaeological community, thus enhancing possibilities for collaborative research and new forms of critical inquiry

    The Visual Computing of Projector-Camera Systems

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    Their increasing capabilities and declining cost make video projectors widespread and established presentation tools. Being able to generate images that are larger than the actual display device virtually anywhere is an interesting feature for many applications that cannot be provided by desktop screens. Several research groups discover this potential by applying projectors in unconventional ways to develop new and innovative information displays that go beyond simple screen presentations. Todays projectors are able to modulate the displayed images spatially and temporally. Synchronized camera feedback is analyzed to support a real-time image correction that enables projections on complex everyday surfaces that are not bound to projector-optimized canvases or dedicated screen configurations. In this talk I will give an overview over our projector-camera-based image correction techniques for geometric warping, radiometric compensation, reduction of global illumination (such as inter-reflections) or view-dependent effects (such as specular reflections), increasing focal depth, and embedding imperceptible codes with a single or with multiple projection units. Thereby, GPU-based real-time rendering and computer vision on graphics hardware are tightly coupled. Such techniques have proved to be useful tools for many real-world applications. Examples include ad-hoc stereoscopic VR/AR visualizations within everyday environments, quality improvements for (semi-)immersive VR projection displays, on-site architectural simulations, augmentations of museum artifacts, video installations in cultural heritage sites, projections onto stage settings during live performances, presentations using mobile (pocket) projectors, outdoor advertisement displays, digital illumination and projections in modern television studios, computer games, and more
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