313 research outputs found

    Enabling the Development and Implementation of Digital Twins : Proceedings of the 20th International Conference on Construction Applications of Virtual Reality

    Get PDF
    Welcome to the 20th International Conference on Construction Applications of Virtual Reality (CONVR 2020). This year we are meeting on-line due to the current Coronavirus pandemic. The overarching theme for CONVR2020 is "Enabling the development and implementation of Digital Twins". CONVR is one of the world-leading conferences in the areas of virtual reality, augmented reality and building information modelling. Each year, more than 100 participants from all around the globe meet to discuss and exchange the latest developments and applications of virtual technologies in the architectural, engineering, construction and operation industry (AECO). The conference is also known for having a unique blend of participants from both academia and industry. This year, with all the difficulties of replicating a real face to face meetings, we are carefully planning the conference to ensure that all participants have a perfect experience. We have a group of leading keynote speakers from industry and academia who are covering up to date hot topics and are enthusiastic and keen to share their knowledge with you. CONVR participants are very loyal to the conference and have attended most of the editions over the last eighteen editions. This year we are welcoming numerous first timers and we aim to help them make the most of the conference by introducing them to other participants

    Probe-based visual analysis of geospatial simulations

    Get PDF
    This work documents the design, development, refinement, and evaluation of probes as an interaction technique for expanding both the usefulness and usability of geospatial visualizations, specifically those of simulations. Existing applications that allow the visualization of, and interaction with, geospatial simulations and their results generally present views of the data that restrict the user to a single perspective. When zoomed out, local trends and anomalies become suppressed and lost; when zoomed in, spatial awareness and comparison between regions become limited. The probe-based interaction model integrates coordinated visualizations within individual probe interfaces, which depict the local data in user-defined regions-of-interest. It is especially useful when dealing with complex simulations or analyses where behavior in various localities differs from other localities and from the system as a whole. The technique has been incorporated into a number of geospatial simulations and visualization tools. In each of these applications, and in general, probe-based interaction enhances spatial awareness, improves inspection and comparison capabilities, expands the range of scopes, and facilitates collaboration among multiple users. The great freedom afforded to users in defining regions-of-interest can cause modifiable areal unit problems to affect the reliability of analyses without the user’s knowledge, leading to misleading results. However, by automatically alerting the user to these potential issues, and providing them tools to help adjust their selections, these unforeseen problems can be revealed, and even corrected

    Accurate geometry reconstruction of vascular structures using implicit splines

    Get PDF
    3-D visualization of blood vessel from standard medical datasets (e.g. CT or MRI) play an important role in many clinical situations, including the diagnosis of vessel stenosis, virtual angioscopy, vascular surgery planning and computer aided vascular surgery. However, unlike other human organs, the vasculature system is a very complex network of vessel, which makes it a very challenging task to perform its 3-D visualization. Conventional techniques of medical volume data visualization are in general not well-suited for the above-mentioned tasks. This problem can be solved by reconstructing vascular geometry. Although various methods have been proposed for reconstructing vascular structures, most of these approaches are model-based, and are usually too ideal to correctly represent the actual variation presented by the cross-sections of a vascular structure. In addition, the underlying shape is usually expressed as polygonal meshes or in parametric forms, which is very inconvenient for implementing ramification of branching. As a result, the reconstructed geometries are not suitable for computer aided diagnosis and computer guided minimally invasive vascular surgery. In this research, we develop a set of techniques associated with the geometry reconstruction of vasculatures, including segmentation, modelling, reconstruction, exploration and rendering of vascular structures. The reconstructed geometry can not only help to greatly enhance the visual quality of 3-D vascular structures, but also provide an actual geometric representation of vasculatures, which can provide various benefits. The key findings of this research are as follows: 1. A localized hybrid level-set method of segmentation has been developed to extract the vascular structures from 3-D medical datasets. 2. A skeleton-based implicit modelling technique has been proposed and applied to the reconstruction of vasculatures, which can achieve an accurate geometric reconstruction of the vascular structures as implicit surfaces in an analytical form. 3. An accelerating technique using modern GPU (Graphics Processing Unit) is devised and applied to rendering the implicitly represented vasculatures. 4. The implicitly modelled vasculature is investigated for the application of virtual angioscopy

    Control for Localization and Visibility Maintenance of an Independent Agent using Robotic Teams

    Get PDF
    Given a non-cooperative agent, we seek to formulate a control strategy to enable a team of robots to localize and track the agent in a complex but known environment while maintaining a continuously optimized line-of-sight communication chain to a fixed base station. We focus on two aspects of the problem. First, we investigate the estimation of the agent\u27s location by using nonlinear sensing modalities, in particular that of range-only sensing, and formulate a control strategy based on improving this estimation using one or more robots working to independently gather information. Second, we develop methods to plan and sequence robot deployments that will establish and maintain line-of-sight chains for communication between the independent agent and the fixed base station using a minimum number of robots. These methods will lead to feedback control laws that can realize this plan and ensure proper navigation and collision avoidance

    Cognitive Principles of Schematisation for Wayfinding Assistance

    Get PDF
    People often need assistance to successfully perform wayfinding tasks in unfamiliar environments. Nowadays, a huge variety of wayfinding assistance systems exists. All these systems intend to present the needed information for a certain wayfinding situation in an adequate presentation. Some wayfinding assistance systems utilize findings for the field of cognitive sciences to develop and design cognitive ergonomic approaches. These approaches aim to be systems with which the users can effortless interact with and which present needed information in a way the user can acquire the information naturally. Therefore it is necessary to determinate the information needs of the user in a certain wayfinding task and to investigate how this information is processed and conceptualised by the wayfinder to be able to present it adequately. Cognitive motivated schematic maps are an example which employ this knowledge and emphasise relevant information and present it in an easily readable way. In my thesis I present a transfer approach to reuse the knowledge of well-grounded knowledge of schematisation techniques from one externalisation such as maps to another externalization such as virtual environments. A analysis of the informational need of the specific wayfinding task route following is done one the hand of a functional decomposition as well as a deep analysis of representation-theoretic consideration of the external representations maps and virtual environments. Concluding from these results, guidelines for transferring schematisation principles between different representation types are proposed. Specifically, this thesis chose the exemplary transfer of the schematisation technique wayfinding choremes from a map presentation into a virtual environment to present the theoretic requirements for a successful transfer. Wayfinding choremes are abstract mental concepts of turning action which are accessible as graphical externalisation integrated into route maps. These wayfinding choremes maps emphasis the turning action along the route by displaying the angular information as prototypes of 45° or 90°. This schematisation technique enhances wayfinding performance by supporting the matching processes between the map representation and the internal mental representation of the user. I embed the concept of wayfinding choremes into a virtual environment and present a study to test if the transferred schematisation technique also enhance the wayfinding performance. The empirical investigations present a successful transfer of the concept of the wayfinding choremes. Depending on the complexity of the route the embedded schematization enhance the wayfinding performance of participants who try to follow a route from memory. Participants who trained and recall the route in a schematised virtual environment make fewer errors than the participants of the unmodified virtual world. This thesis sets an example of the close research circle of cognitive behavioural studies to representation-theoretical considerations to applications of wayfinding assistance and their evaluations back to new conclusions in cognitive science. It contributes an interdisciplinary comprehensive inspection of the interplay of environmental factors and mental processes on the example of angular information and mental distortion of this information

    Cognitive Principles of Schematisation for Wayfinding Assistance

    Get PDF
    People often need assistance to successfully perform wayfinding tasks in unfamiliar environments. Nowadays, a huge variety of wayfinding assistance systems exists. All these systems intend to present the needed information for a certain wayfinding situation in an adequate presentation. Some wayfinding assistance systems utilize findings for the field of cognitive sciences to develop and design cognitive ergonomic approaches. These approaches aim to be systems with which the users can effortless interact with and which present needed information in a way the user can acquire the information naturally. Therefore it is necessary to determinate the information needs of the user in a certain wayfinding task and to investigate how this information is processed and conceptualised by the wayfinder to be able to present it adequately. Cognitive motivated schematic maps are an example which employ this knowledge and emphasise relevant information and present it in an easily readable way. In my thesis I present a transfer approach to reuse the knowledge of well-grounded knowledge of schematisation techniques from one externalisation such as maps to another externalization such as virtual environments. A analysis of the informational need of the specific wayfinding task route following is done one the hand of a functional decomposition as well as a deep analysis of representation-theoretic consideration of the external representations maps and virtual environments. Concluding from these results, guidelines for transferring schematisation principles between different representation types are proposed. Specifically, this thesis chose the exemplary transfer of the schematisation technique wayfinding choremes from a map presentation into a virtual environment to present the theoretic requirements for a successful transfer. Wayfinding choremes are abstract mental concepts of turning action which are accessible as graphical externalisation integrated into route maps. These wayfinding choremes maps emphasis the turning action along the route by displaying the angular information as prototypes of 45° or 90°. This schematisation technique enhances wayfinding performance by supporting the matching processes between the map representation and the internal mental representation of the user. I embed the concept of wayfinding choremes into a virtual environment and present a study to test if the transferred schematisation technique also enhance the wayfinding performance. The empirical investigations present a successful transfer of the concept of the wayfinding choremes. Depending on the complexity of the route the embedded schematization enhance the wayfinding performance of participants who try to follow a route from memory. Participants who trained and recall the route in a schematised virtual environment make fewer errors than the participants of the unmodified virtual world. This thesis sets an example of the close research circle of cognitive behavioural studies to representation-theoretical considerations to applications of wayfinding assistance and their evaluations back to new conclusions in cognitive science. It contributes an interdisciplinary comprehensive inspection of the interplay of environmental factors and mental processes on the example of angular information and mental distortion of this information

    HyperBody: An Experimental VR Game Exploring the Cosmotechnics of Game Fandom through a Posthumanist Lens

    Get PDF
    Interdependencies among ACGN (Anime, Comics, Games, and Novels) communities in China, Hong Kong, and Taiwan are growing. However, game studies and fan studies remain distinct disciplines. This cross-disciplinary thesis bridges this gap by investigating "game-fandom" practices in VR production, defined as the fusion of game and fan studies within the ACGN context. Drawing from Yuk Hui's "cosmotechnics" and Karen Barad's posthumanist perspective, this research reconsiders the relationship between cosmology, morality, and technology (Hui 2017). It employs "intra-action" to emphasise the indivisible, dynamic relations among specified objects (Barad 2007). Cultural practices in C-pop idol groups, Chinese BL (Boys' Love) novels, science fiction, and modding communities are analysed, illuminating the ACGN fandom's cultural, technological, and affective dimensions. This work features the creation, description, and evaluation of an experimental VR game, "HyperBody", which integrates the written thesis by reflecting game-fandom's cosmotechnics and intra-actions. The thesis offers two significant contributions: "queer tuning", a theory illuminating new cultural, technological, and affective turns within fandom and computational art, and a "diffractive" approach, forming a methodological framework for posthuman performative contexts. This diffractive framework enables practical contributions such as creating and describing experimental VR productions using the sound engine. It also highlights a thorough evaluation approach reconciling quantitative and qualitative methods in VR production analysis, investigating affective experiences, and exploring how users engage creatively with queer VR gamespaces. These contributions foster interdisciplinary collaboration among VR, game design, architecture, and fandom studies, underscoring the inextricable link among ethics, ontology, and epistemology, culminating in a proposed ethico-onto-epistem-ological framework
    • …
    corecore