New distributed virtual TV set architecture for a synergistic operation of sensors and improved interaction between real and virtual worlds

A virtual TV set is a studio that is able to combine recorded actors and objects with computer generated virtual environments in real time. In order to achieve this combination seamlessly, in an ideal configuration, several elements such as cameras, objects and people should be tracked so that all their actions on the stage have a corresponding effect in the virtual world. However, in the actual professional virtual TV sets, the tracking possibilities are quite limited because of the hardware and software architecture used, which has not had a major evolution since the first prototypes presented in the nineties. This traditional architecture uses to be rigid, including just one monolithic tracking system and low levels of interactivity. In this paper, a new distributed, flexible and scalable hardware and software architecture that allows the inclusion of multiple kinds of devices in parallel is introduced. It breaks with the traditional structure of the virtual TV sets, opening the technology to an easier inclusion of new devices without the need of updating the proprietary software of the set, thus facilitating its future evolution. The design, implementation and test of this architecture, through the adaptation of a traditional virtual TV set, is presented. The tests are developed through the inclusion of modern devices (in our case Optitrack infrared cameras, Microsoft Kinect V2 and Leap Motion) that, through a synergistic operation, allow the system to solve some traditional drawbacks of this technology such as free and multiple object and camera tracking, presenter natural interaction and automatic distance keying.     

Creating ambient music spaces in real and virtual worlds

Sound and, specifically, music is a medium that is used for a wide range of purposes in different situations in very different ways. Ways for music selection and consumption range from completely passive, almost unnoticed perception of background sound environments to the very specific selection of a particular recording of a piece of music with a specific orchestra and conductor at a certain event. Different systems and interfaces exist for the broad range of needs in music consumption. Locating a particular recording is well supported by traditional search interfaces via metadata. Other interfaces support the automatic creation of playlists via artist or album selection, up to more artistic installations of sound environments that users can navigate through. In this paper we present a set of systems that support the creation of as well as the navigation in musical spaces, both in the real world as well as in virtual environments. We show common principles and point out further directions for a more direct coupling of the various spaces and interaction methods, creating ambient sound environments and providing organic interaction with music for different purposes.

Flocking techniques to naturally support navigation in large and open virtual worlds

This paper proposes and explores the use of flocking techniques to naturally support navigation in large and open virtual environments. The proposed approach comprises both a flocking algorithm (which simulates the behavior of a flock of virtual beings) and a control algorithm (which manages the navigation information and parameterizes the flocking behavior). The model was developed and evaluated through a user study which investigated whether the addition of the proposed model has an effect on the user experience when exploring a virtual environment. In the research the experiment group explored a virtual environment where the proposed flocking model was added to suggest places to visit. The participants were not informed about the guiding abilities of the virtual animals. The control group explored the same virtual environment without the animal flock. The impact of both cases was compared. The results indicate that the proposed model is adequate to suggest places to visit in large and open virtual worlds.     

How to address group dynamics in virtual worlds

The study of group dynamics highlights the activity in the group in terms of its performance and communication. The experience of facilitating virtual communities and teams (Eunice and Kimball in , 1997) suggests that groups go through the same stages either in face-to-face or in online mode. The paper brings together a theoretical framework based on the literature on virtual communities, Gestalt systems and online facilitation in order to address the issue of electronic togetherness, in particular from a group dynamics perspective. The empirical work on which the paper is based is an observation of a group of students in a training set playing a decision-making game. The model of Tuckman (Tuckman in Psychol Bull 63:384–399, 1965; Tuckman and Jensen in Group Organ Stud 2:419–427, 1977) is used as a framework within which to discuss the findings of the case. The paper finishes with concrete recommendations for facilitators of online communities and designers of the electronic spaces where these communities operate.     

Tomorrow''s space: Journey to the virtual worlds

The new technology of Virtual Reality (VR) provides a revolutionary way to improve the coupling of the human operator to the computing machine. In a VR system, the goal is to remove the distinction between the system and the user's environment, as compared to the conventional relationship between the user and a computer. Thus, to be able to immerse the user in his artificial world, the VR system shall make use simultaneously of the human senses and of his cognitive capacities. In practice, the VR system is the integration of computer graphics and various sensor and actuator technology to create the illusion of immersion in a computer generated reality.

VR has therefore been identified as a good candidate for the Technological Research Programme of the European Space Agency (ESA). In 1991, the Agency has initiated research activities in the field of VR to identify its potential applications for European space programmes. A generic VR system has been developed allowing the Agency to evaluate the performance of VR technology and to define research activities for the coming years. The aims are to build a European expertise in VR technology and to demonstrate the applicability of VR to space programmes.     

Towards an architecture for virtual enterprises

An approach to the design of an architecture for industrial virtual enterprises (VE), with special emphasis on the identification of main functional requirements, is presented. First, a discussion of the various types of virtual enterprises is provided. Some classification scenarios and discussions of the modelling and reengineering tools and methodologies are described. Due to the importance of the information flows and management in the VE, one section is merely devoted to the analysis of the appropriateness of a federated information management approach. This work is based on and represents the ongoing activities in two European Union funded projects; the Esprit PRODNET II and the INCO-DC SCM+ projects.     

A declarative approach to procedural modeling of virtual worlds

With the ever increasing costs of manual content creation for virtual worlds, the potential of creating it automatically becomes too attractive to ignore. However, for most designers, traditional procedural content generation methods are complex and unintuitive to use, hard to control, and generated results are not easily integrated into a complete and consistent virtual world.We introduce a novel declarative modeling approach that enables designers to concentrate on stating what they want to create instead of on describing how they should model it. It aims at reducing the complexity of virtual world modeling by combining the strengths of semantics-based modeling with manual and procedural approaches. This article describes two of its main contributions to procedural modeling of virtual worlds: interactive procedural sketching and virtual world consistency maintenance. We discuss how these techniques, integrated in our modeling framework SketchaWorld, build up to enable designers to create a complete 3D virtual world in minutes. Procedural sketching provides a fast and more intuitive way to model virtual worlds, by letting designers interactively sketch their virtual world using high-level terrain features, which are then procedurally expanded using a variety of integrated procedural methods. Consistency maintenance guarantees that the semantics of all terrain features is preserved throughout the modeling process. In particular, it automatically solves conflicts possibly emerging from interactions between terrain features.We believe that these contributions together represent a significant step towards providing more user control and flexibility in procedural modeling of virtual worlds. It can therefore be expected that by further reducing its complexity, virtual world modeling will become accessible to an increasingly broad group of users.     

Beyond e-business models: the road to virtual worlds

Virtual Worlds (or, VWs) are an intriguing field of research. In particular, VWs appear to create new opportunities for integrating the business of the firm with Information Technology (or, IT). This article is a first attempt to address the topic of how owning and maintaining a VW can impact on the business models of firms and on the literature on business models, and VWs are examined in order to understand the relationship between them. A qualitative methodology is proposed to sketch a radar map framework, which is able to identify value drivers and the subsequent impact on elements of value proposition. Although they need to be tested and verified, the findings provided in this work might offer support for firms looking to VWs as a new way to implement a winning business model. Finally, suggestions for empowering future research are proposed and examined.     

Virtual goods,real goals: Exploring means-end goal structures of consumers in social virtual worlds

The aim of this study is to understand consumer goals for virtual consumption in social virtual worlds. Using a means-end chain approach, interviews with 93 users were analyzed to produce a hierarchical goal map, revealing that virtual consumption enables a diversity of goals beyond the previously identified experiential goals. The article's theoretical contributions include: (1) extending our understanding of user goals/goal relationships for virtual activities and (2) developing virtual liminoid theory, which describes transitions between users’ real-world and virtual identities and virtual consumption as a transition catalyst. The study illustrates the value of a goal focus for future research on user behavior in virtual worlds.     

Pre-service teachers’ perspectives on using scenario-based virtual worlds in science education

This paper presents the findings of a study on the current knowledge and attitudes of pre-service teachers on the use of scenario-based multi-user virtual environments in science education. The 28 participants involved in the study were introduced to Virtual Singapura, a multi-user virtual environment, and completed an open-ended questionnaire. Data from the questionnaire indicated that gender and current computer game use were likely to affect the perceived benefits of using virtual worlds in a classroom setting. Behavior management was seen as being a constraining factor on a pre-service teacher’s willingness to use a virtual world in the future. Overall, the results of the study indicate that pre-service teachers as a result of their use of Virtual Singapura are both aware of virtual worlds and have a reasonable understanding of both their potential advantages and disadvantages within a classroom setting.     

Modelling virtual cities dedicated to behavioural animation

In order to populate virtual cities, it is necessary to specify the behaviour of dynamic entities such as pedestrians or car drivers. Since a complete mental model based on vision and image processing cannot be constructed in real time using purely geometrical information, higher levels of information are needed in a model of the virtual environment. For example, the autonomous actors of a virtual world would exploit the knowledge of the environment topology to navigate through it. In this article, we present a model of virtual urban environments using structures and information suitable for behavioural animations. Thanks to this knowledge, autonomous virtual actors can behave like pedestrians or car drivers in a complex city environment. A city modeler has been designed, using this model of urban environment, and enables complex urban environments for behavioural animation to be automatically produced.     

Spatial proximity to others determines how humans inhabit virtual worlds

Highly immersive three-dimensional virtual worlds have emerged as a popular medium for human social interactions. These environments enable multimodal sensory engagement and provide an immersive graphical representation of physical space where users can interact via avatars. However, when compared to two-dimensional virtual settings such as chats, virtual worlds impose constraints on social interactions due to the physical distance between individuals. Using the popular platform of Second Life as a model, we examined how humans manage this interindividual distance in virtual worlds. Taking advantage of methods developed in population ecology, we investigated how avatars are distributed in relation to each other to populate a virtual world. Our results revealed a striking dichotomy in the spatial relationships between avatars. Considerable aggregation, largely independent of population density, was observed alongside surprisingly marked physical isolation. These findings demonstrate that the spatial proximity to others determines how humans inhabit virtual worlds.     

Towards an open architecture for vector GIS

A range of open source software tools are now available to the Geographical Information Systems (GIS) analyst. However these tools are not necessarily interoperable and rarely significantly interoperable with proprietary systems. The open architectures, which have been developed for web-oriented systems, together with those proposed by the Open Geospatial Consortium (OGC), suggest that an open GIS architecture could be developed as an alternative to proprietary systems. The architecture would use open source components to store, translate, analyse, render and visualise GI data and would escape many of the problems of monolithic systems. Particularly what is proposed permits the loose coupling of any number of components and data stores in a manner that is both open and flexible. This paper proposes such an architecture and focuses on determining the suitability of Scalable Vector Graphics (SVG), an open vector-oriented eXtensible Markup Language (XML) grammar, as a significant component of such architecture. SVG is shown as an effective means of rendering GI data, not least because of its compatibility with the WC3 Document Object Model (DOM), permitting GIS-specific client tools to be written and transmitted to the web browser along with the SVG pages. While realising that the technology is in its infancy, the conclusion reached is that SVG currently provides a powerful solution and has enormous future potential.     

Predicting users' return to virtual worlds: a social perspective

Virtual worlds or three‐dimensional computer‐based simulated environments have received considerable attention as platforms for entertainment, education and commerce. In contrast to a web site, for example, where a user interacts with a two‐dimensional site, virtual worlds provide a platform in which users can interact with other individuals, sometimes including strangers, within three‐dimensional environments. Virtual worlds afford a form of ‘socialness’ unlike many other technologies, often motivating a user – by virtue of these social experiences – to return. Drawing on the Spatial Model of Interaction and Awareness‐Attention Theory, we demonstrate that besides social aspects, which include social awareness and social perception, flow experience, which is the mental state of being fully absorbed and somewhat lost in time, is an essential ingredient in an individual's decision to return to a virtual world. We also demonstrate how characteristics of the technology are linked to the social aspects experienced in virtual worlds. A laboratory study conducted in a virtual world, Second Life, supports our assertions and identifies state predictors of flow that influence individuals' intentions to return to the virtual world environment.     

Dr. Jekyll vis-à-vis Mr. Hyde: Personality variation between virtual and real worlds

Organizations use virtual-worlds to enhance group discussion; it allows an individual to decouple his or her rendered from actual behavior; resulting in others perceiving him or her to have two or more personalities. Building on self-regulation theory, we examined how satisfaction in the virtual-world was affected by these personality differences. A field study was conducted to attempt to understand this; it involved 297 students engaged in a virtual tutorial group using Second Life. We found that small variations in personality between the virtual and real world groups (such as being helpful, sociable, seeking recognition, or submissive) could lead to greater satisfaction of the discussion.     

System architecture evaluation using modular performance analysis: a case study

Performance analysis plays an increasingly important role in the design of embedded real-time systems. Time-to-market pressure in this domain is high while the available implementation technology is often pushed to its limit to minimize cost. This requires analysis of performance as early as possible in the life cycle. Simulation-based techniques are often not sufficiently productive. We present an alternative, analytical, approach based on Real-Time Calculus. Modular performance analysis is presented through a case study in which several candidate architectures are evaluated for a distributed in-car radio navigation system. The analysis is efficient due to the high abstraction level of the model, which makes the technique suitable for early design exploration. This work has been carried out as part of the boderc project under the responsibility of the Embedded Systems Institute     

Whole-body modelling of people from multiview images to populate virtual worlds

In this paper a new technique is introduced for automatically building recognisable, moving 3D models of individual people. A set of multiview colour images of a person is captured from the front, sides and back by one or more cameras. Model-based reconstruction of shape from silhouettes is used to transform a standard 3D generic humanoid model to approximate a person's shape and anatomical structure. Realistic appearance is achieved by colour texture mapping from the multiview images. The results show the reconstruction of a realistic 3D facsimile of the person suitable for animation in a virtual world. The system is inexpensive and is reliable for large variations in shape, size and clothing. This is the first approach to achieve realistic model capture for clothed people and automatic reconstruction of animated models. A commercial system based on this approach has recently been used to capture thousands of models of the general public.