System Architecture of a Mixed Reality Framework

In this paper the software architecture of a framework which simplifies the development of applications in the area of Virtual and Augmented Reality is presented. It is based on VRML/X3D to enable rendering of audio-visual information. We extended our VRML rendering system by a device management system that is based on the concept of a data-flow graph. The aim of the system is to create Mixed Reality (MR) applications simply by plugging together small prefabricated software components, instead of compiling monolithic C++ applications. The flexibility and the advantages of the presented framework are explained on the basis of an exemplary implementation of a classic Augmented Realityapplication and its extension to a collaborative remote expert scenario.

The MIRELA framework: modeling and analyzing mixed reality applications using timed automata

Mixed Reality (MR) aims to link virtual entities with the real world and has many applications such as military and medical domains [JBL+00, NFB07]. In many MR systems and more precisely in augmented scenes, one needs the application to render the virtual part accurately at the right time. To achieve this, such systems acquire data related to the real world from a set of sensors before rendering virtual entities. A suitable system architecture should minimize the delays to keep the overall system delay (also called end-to-end latency) within the requirements for real-time performance. In this context, we propose a compositional modeling framework for MR software architectures in order to specify, simulate and validate formally the time constraints of such systems. Our approach is first based on a functional decomposition of such systems into generic components. The obtained elements as well as their typical interactions give rise to generic representations in terms of timed automata. A whole system is then obtained as a composition of such defined components. To write specifications, a textual language named MIRELA (MIxed REality LAnguage) is proposed along with the corresponding compilation tools. The generated output contains timed automata in UPPAAL format for simulation and verification of time constraints. These automata may also be used to generate source code skeletons for an implementation on a MR platform. The approach is illustrated first on a small example. A realistic case study is also developed. It is modeled by several timed automata synchronizing through channels and including a large number of time constraints. Both systems have been simulated in UPPAAL and checked against the required behavioral properties.

Copyright Exhaustion Rationales and Used Software: A Law and Economics Approach to Oracle v. UsedSoft

This article aims to provide courts and policymakers with an analytical framework that, building upon the traditional rationales of IP exhaustion doctrine, identifies factors which advocate for a modulation or flexibilization of the role of exhaustion in copyright law. Factors include (i) the personal features of acquirers of copies of copyrighted works, distinguishing between consumers and commercial users; (ii) whether post-sale restrictions have been adequately communicated to acquirers and have been agreed in the contract or license; (iii) the degree of complexity of the acquired goods and their prospects of productive uses and interoperability; (iv) the role of other exclusive rights in providing rightholders with indirect control over uses of the copies in the aftermarket; (v) the impact of post-sale restraints in preventing opportunism in long-term contracts and in reducing deadweight losses created by IP pricing; and (vi) the temporal scope of post-sale restraints. After setting out this analytical framework, the ECJ Judgement in Oracle v. UsedSoft is discussed.