31 research outputs found
Model and Tools for Integrating IoT into Mixed Reality Environments: Towards a Virtual-Real Seamless Continuum
International audienceThis paper introduces a new software model and new tools for managing indoor smart environments (smart home, smart building , smart factories, etc.) thanks to MR technologies. Our fully-integrated solution is mainly based on a software modelization of connected objects used to manage them independently from their actual nature: these objects can be simulated or real. Based on this model our goal is to create a continuum between a real smart environment and its 3D digital twin in order to simulate and manipulate it. Therefore, two kinds of tools are introduced to leverage this model. First, we introduce two complementary tools, an AR and a VR one, for the creation of the digital twin of a given smart environment. Secondly, we propose 3D interactions and dedicated metaphors for the creation of automation scenarios in the same VR application. These scenarios are then converted to a Petri-net based model that can be edited later by expert users. Adjusting the parameters of our model allows to navigate on the continuum in order to use the digital twin for simulation, deployment and real/virtual synchronization purposes. These different contributions and their benefits are illustrated thanks to the automation configuration of a room in our lab
Statistical Model of Shape Moments with Active Contour Evolution for Shape Detection and Segmentation
This paper describes a novel method for shape representation and robust image segmentation. The proposed method combines two well known methodologies, namely, statistical shape models and active contours implemented in level set framework. The shape detection is achieved by maximizing a posterior function that consists of a prior shape probability model and image likelihood function conditioned on shapes. The statistical shape model is built as a result of a learning process based on nonparametric probability estimation in a PCA reduced feature space formed by the Legendre moments of training silhouette images. A greedy strategy is applied to optimize the proposed cost function by iteratively evolving an implicit active contour in the image space and subsequent constrained optimization of the evolved shape in the reduced shape feature space. Experimental results presented in the paper demonstrate that the proposed method, contrary to many other active contour segmentation methods, is highly resilient to severe random and structural noise that could be present in the data
An FPGA-based pipeline for micropolarizer array imaging
The enhancement of current camera performances, in terms of framerate, image resolution and pixel width, has direct consequences on the amount of resources needed to process video data. Stokes imaging permits to estimate polarization of light and create multiple polarization descriptors of the scene. Therefore, such video cameras need fast processing for critical applications like overseeing, defect detection or surface characterization. An FPGA hardware implementation of Stokes processing is presented here that embeds dedicated pipeline for micropolarizer array sensors. An optimized fixed-point pipeline is used to compute polarimetric images, i.e. Stokes vector, degree of polarization and angle of polarization. Simulation and experimental studies are done. The hardware design contains parallel processing, low latency and low power and could meet actual real-time and embeddable requirements for smart camera systems
OPA1: 516 unique variants and 831 patients registered in an updated centralized Variome database
BACKGROUND: The dysfunction of OPA1, a dynamin GTPase involved in mitochondrial fusion, is responsible for a large spectrum of neurological disorders, each of which includes optic neuropathy. The database dedicated to OPA1 ( https://www.lovd.nl/OPA1 ), created in 2005, has now evolved towards a centralized and more reliable database using the Global Variome shared Leiden Open-source Variation Database (LOVD) installation.
RESULTS: The updated OPA1 database, which registers all the patients from our center as well as those reported in the literature, now covers a total of 831 patients: 697 with isolated dominant optic atrophy (DOA), 47 with DOA "plus", and 83 with asymptomatic or unclassified DOA. It comprises 516 unique OPA1 variants, of which more than 80% (414) are considered pathogenic. Full clinical data for 118 patients are documented using the Human Phenotype Ontology, a standard vocabulary for referencing phenotypic abnormalities. Contributors may now make online submissions of phenotypes related to OPA1 mutations, giving clinical and molecular descriptions together with detailed ophthalmological and neurological data, according to an international thesaurus.
CONCLUSIONS: The evolution of the OPA1 database towards the LOVD, using unified nomenclature, should ensure its interoperability with other databases and prove useful for molecular diagnoses based on gene-panel sequencing, large-scale mutation statistics, and genotype-phenotype correlations
Using DBpedia as a knowledge source for culture-related user modelling questionnaires
In the culture domain, questionnaires are often used to obtain profiles of users for adaptation. Creating questionnaires requires subject matter experts and diverse content, and often does not scale to a variety of cultures and situations. This paper presents a novel approach that is inspired by crowdwisdom and takes advantage of freely available structured linked data. It presents a mechanism for extracting culturally-related facts from DBpedia, utilised as a knowledge source in an interactive user modelling system. A user study, which examines the system usability and the accuracy of the resulting user model, demonstrates the potential of using DBpedia for generating culture-related user modelling questionnaires and points at issues for further investigation
Contextual Metadata in Digital Aggregations: Application of Collection-Level Subject Metadata and Its Role in User Interactions and Information Retrieval
Article discussing a study of contextual metadata in digital aggregations. Results of this study prove importance of provision of collection-level metadata in general and subject metadata in particular to enhance user experiences and information retrieval in digital libraries
High-speed imaging polarimetry using liquid crystal modulators
This paper deals with dynamic polarimetric imaging techniques. The basics of
modern polarimetry have been known for one and a half century, but no practical
high-speed implementation providing the full polarization information is
currently available. Various methods are reviewed which prove to be a trade-off
between the complexity of the optical set-up and the amount of polarimetric
information they provide (ie the number of components of the Stokes vector).
Techniques using liquid crystal devices, incepted in the late 1990's, are
emphasized. Optical set-ups we implemented are presented. We particularly focus
on high-speed techniques (i.e. faster than 200 Hz) using ferroelectric liquid
crystal devices
High-speed imaging polarimetry using liquid crystal modulators
This paper deals with dynamic polarimetric imaging techniques. The basics of modern polarimetry have been known for one and a half century, but no practical high-speed implementation providing the full polarization information is currently available. Various methods are reviewed which prove to be a trade-off between the complexity of the optical set-up and the amount of polarimetric information they provide (ie the number of components of the Stokes vector). Techniques using liquid crystal devices, incepted in the late 1990's, are emphasized. Optical set-ups we implemented are presented. We particularly focus on high-speed techniques (i.e. faster than 200 Hz) using ferroelectric liquid crystal devices