22 research outputs found

    Predictive Rendering

    Get PDF

    Non-destructive identification of fibre orientation in multi-ply biaxial laminates using contact temperature sensors

    Get PDF
    Fibre orientation within composite structures dictates the material properties of the laminate once cured. The ability to accurately and automatically assess fibre orientation of composite parts is a significant enabler in the goal to optimise the established processes within aftermarket aerospace industries. Incorrect ply lay-up results in a structure with undesirable material properties and as such, has the potential to fail under safe working loads. Since it is necessary to assure structural integrity during re-manufacture and repair assessment, the paper demonstrates a novel method of readily and non-destructively determining fibre orientation throughout multi-ply Biaxial woven composite laminates using point temperature contact sensors and data analysis techniques. Once cured, only the outermost laminates are visible to assess orientation. The inspection method is conducted visually, with reference guides to allow for rapid adoption with minimum training, as well as harnessing established temperature sensors within the Maintenance Repair and Overhaul (MRO) environment. The system is amenable to integration within existing repair/re-manufacture processes without significant impact to process flow. The method is able to identify noisy samples with an accuracy, precision and recall of 0.9, and for synthetically created samples of double the cure ply thickness, a precision of 0.75, a recall of 0.7 and an accuracy of 0.87

    Adaptive face modelling for reconstructing 3D face shapes from single 2D images

    Get PDF
    Example-based statistical face models using principle component analysis (PCA) have been widely deployed for three-dimensional (3D) face reconstruction and face recognition. The two common factors that are generally concerned with such models are the size of the training dataset and the selection of different examples in the training set. The representational power (RP) of an example-based model is its capability to depict a new 3D face for a given 2D face image. The RP of the model can be increased by correspondingly increasing the number of training samples. In this contribution, a novel approach is proposed to increase the RP of the 3D face reconstruction model by deforming a set of examples in the training dataset. A PCA-based 3D face model is adapted for each new near frontal input face image to reconstruct the 3D face shape. Further an extended Tikhonov regularisation method has been

    From Sensor to Observation Web with Environmental Enablers in the Future Internet

    Get PDF
    This paper outlines the grand challenges in global sustainability research and the objectives of the FP7 Future Internet PPP program within the Digital Agenda for Europe. Large user communities are generating significant amounts of valuable environmental observations at local and regional scales using the devices and services of the Future Internet. These communities’ environmental observations represent a wealth of information which is currently hardly used or used only in isolation and therefore in need of integration with other information sources. Indeed, this very integration will lead to a paradigm shift from a mere Sensor Web to an Observation Web with semantically enriched content emanating from sensors, environmental simulations and citizens. The paper also describes the research challenges to realize the Observation Web and the associated environmental enablers for the Future Internet. Such an environmental enabler could for instance be an electronic sensing device, a web-service application, or even a social networking group affording or facilitating the capability of the Future Internet applications to consume, produce, and use environmental observations in cross-domain applications. The term ?envirofied? Future Internet is coined to describe this overall target that forms a cornerstone of work in the Environmental Usage Area within the Future Internet PPP program. Relevant trends described in the paper are the usage of ubiquitous sensors (anywhere), the provision and generation of information by citizens, and the convergence of real and virtual realities to convey understanding of environmental observations. The paper addresses the technical challenges in the Environmental Usage Area and the need for designing multi-style service oriented architecture. Key topics are the mapping of requirements to capabilities, providing scalability and robustness with implementing context aware information retrieval. Another essential research topic is handling data fusion and model based computation, and the related propagation of information uncertainty. Approaches to security, standardization and harmonization, all essential for sustainable solutions, are summarized from the perspective of the Environmental Usage Area. The paper concludes with an overview of emerging, high impact applications in the environmental areas concerning land ecosystems (biodiversity), air quality (atmospheric conditions) and water ecosystems (marine asset management)

    Sixth Biennial Report : August 2001 - May 2003

    No full text

    Fifth Biennial Report : June 1999 - August 2001

    No full text

    Step into the Void: A Study of Spatial Perception in Virtual Reality

    Get PDF
    The introduction of virtual reality (VR) into the architectural profession offers an unprecedented opportunity to experience unbuilt designs at full scale. The premise of the technology is that it gives users the illusion of being in another place by replacing their field of vision with a digital image. While VR technology, for the most part, can only simulate visual sensations at this point in its development, it has demonstrated in various applications that the immersiveness of the medium can elicit visceral reactions. This potential could be leveraged to expand the capacity of architects to convey the complexities of architectural space in an easily comprehensible form. Because VR is relatively unfamiliar, especially in architecture, there is a need to identify the technology’s strengths and weaknesses so that it can be appropriately utilized in practice. The goal of this thesis is to further the understanding of interior spatial perception in VR. Perception of interior space is affected by many visual factors, like the shape of the space, details, and how crowded the space is. In order to test the impact of these aspects of spatial perception in VR, a set of experiments were conducted at the School of Architecture. Participants engaged in a series of exercises where they would attempt to position the walls and ceilings of a series of rooms to match a given set of dimensions. Each room is designed slightly differently to test the aforementioned aspects of spatial perception. These exercises are completed once with orthogonal architectural drawings and once with VR. Some results from the experiments might indicate that atmospheric design elements may be more impactful when represented in VR, but further research is required. In most cases, participants were more accurate when using orthogonal drawings to complete the exercises. However, participants created rooms that were more similar to each other when completing the exercises in VR, which suggests that VR might be more effective than orthogonal drawings in imparting a common understanding of space to different people, an encouraging sign that VR is an effective medium for communication

    Realistic simulation and animation of clouds using SkewT-LogP diagrams

    Get PDF
    Nuvens e clima sĂŁo tĂłpicos importantes em computação grĂĄfica, nomeadamente na simulação e animação de fenĂłmenos naturais. Tal deve-se ao facto de a simulação de fenĂłmenos naturais−onde as nuvens estĂŁo incluĂ­das−encontrar aplicaçÔes em filmes, jogos e simuladores de voo. Contudo, as tĂ©cnicas existentes em computação grĂĄfica apenas permitem representaçÔes de nuvens simplificadas, tornadas possĂ­veis atravĂ©s de dinĂąmicas fictĂ­cias que imitam a realidade. O problema que este trabalho pretende abordar prende-se com a simulação de nuvens adequadas para utilização em ambientes virtuais, isto Ă©, nuvens com dinĂąmica baseada em fĂ­sica que variam ao longo do tempo. Em meteorologia Ă© comum usar tĂ©cnicas de simulação de nuvens baseadas em leis da fĂ­sica, contudoossistemasatmosfĂ©ricosdeprediçãonumĂ©ricasĂŁocomputacionalmente pesados e normalmente possuem maior precisĂŁo numĂ©rica do que o necessĂĄrio em computação grĂĄfica. Neste campo, torna-se necessĂĄrio direcionar e ajustar as caracterĂ­sticas fĂ­sicas ou contornar a realidade de modo a atingir os objetivos artĂ­sticos, sendo um fator fundamental que faz com que a computação grĂĄfica se distinga das ciĂȘncias fĂ­sicas. Contudo, simulaçÔes puramente baseadas em fĂ­sica geram soluçÔes de acordo com regras predefinidas e tornam-se notoriamente difĂ­ceis de controlar. De modo a enfrentar esses desafios desenvolvemos um novo mĂ©todo de simulação de nuvens baseado em fĂ­sica que possui a caracterĂ­stica de ser computacionalmente leve e simula as propriedades dinĂąmicas relacionadas com a formação de nuvens. Este novo modelo evita resolver as equaçÔes fĂ­sicas, ao apresentar uma solução explĂ­cita para essas equaçÔes atravĂ©s de diagramas termodinĂąmicos SkewT/LogP. O sistema incorpora dados reais de forma a simular os parĂąmetros necessĂĄrios para a formação de nuvens. É especialmente adequado para a simulação de nuvens cumulus que se formam devido ao um processo convectivo. Esta abordagem permite nĂŁo sĂł reduzir os custos computacionais de mĂ©todos baseados em fĂ­sica, mas tambĂ©m fornece a possibilidade de controlar a forma e dinĂąmica de nuvens atravĂ©s do controlo dos nĂ­veis atmosfĂ©ricos existentes no diagrama SkewT/LogP. Nestatese,abordĂĄmostambĂ©mumoutrodesafio,queestĂĄrelacionadocomasimulação de nuvens orogrĂĄficas. Do nosso conhecimento, esta Ă© a primeira tentativa de simular a formação deste tipo de nuvens. A novidade deste mĂ©todo reside no fato de este tipo de nuvens serem nĂŁo convectivas, oque se traduz nocĂĄlculodeoutrosnĂ­veis atmosfĂ©ricos. AlĂ©m disso, atendendo a que este tipo de nuvens se forma sobre montanhas, Ă© tambĂ©m apresentadoumalgoritmoparadeterminarainfluĂȘnciadamontanhasobreomovimento da nuvem. Em resumo, esta dissertação apresenta um conjunto de algoritmos para a modelação e simulação de nuvens cumulus e orogrĂĄficas, recorrendo a diagramas termodinĂąmicos SkewT/LogP pela primeira vez no campo da computação grĂĄfica.Clouds and weather are important topics in computer graphics, in particular in the simulation and animation of natural phenomena. This is so because simulation of natural phenomena−where clouds are included−find applications in movies, games and flight simulators. However, existing techniques in computer graphics only offer the simplified cloud representations, possibly with fake dynamics that mimic the reality. The problem that this work addresses is how to find realistic simulation of cloud formation and evolution, that are suitable for virtual environments, i.e., clouds with physically-based dynamics over time. It happens that techniques for cloud simulation are available within the area of meteorology, but numerical weather prediction systems based on physics laws are computationally expensive and provide more numerical accuracy than the required accuracy in computer graphics. In computer graphics, we often need to direct and adjust physical features, or even to bend the reality, to meet artistic goals, which is a key factor that makes computer graphics distinct from physical sciences. However, pure physically-based simulations evolve their solutions according to pre-set physics rules that are notoriously difficult to control. In order to face these challenges we have developed a new lightweight physically-based cloudsimulationschemethatsimulatesthedynamicpropertiesofcloudformation. This new model avoids solving the physically-based equations typically used to simulate the formation of clouds by explicitly solving these equations using SkewT/LogP thermodynamic diagrams. The system incorporates a weather model that uses real data to simulate parameters related to cloud formation. This is specially suitable to the simulation of cumulus clouds, which result from a convective process. This approach not only reduces the computational costs of previous physically-based methods, but also provides a technique to control the shape and dynamics of clouds by handling the cloud levels in SkewT/LogP diagrams. In this thesis, we have also tackled a new challenge, which is related to the simulation oforographic clouds. From ourknowledge, this isthefirstattempttosimulatethis type of cloud formation. The novelty in this method relates to the fact that these clouds are non-convective, so that different atmospheric levels have to be determined. Moreover, since orographic clouds form over mountains, we have also to determine the mountain influence in the cloud motion. In summary, this thesis presents a set of algorithms for the modelling and simulation of cumulus and orographic clouds, taking advantage of the SkewT/LogP diagrams for the first time in the field of computer graphics
    corecore