Search results for " sensor"
showing 10 items of 1714 documents
Divu brīvības pakāpju savienojumu noteikšana ar inerciālajiem sensoriem
2022
Inerciālie sensori ir plaši izmantoti, lai no to datiem aprēķinātu un aprakstītu fizikālu objektu orientācijas. Lai iegūtu orientāciju, kam nav laikā uzkrājoša kļūda, papildus bieži lieto magnētiskā lauka sensorus, kuru mērījumi reālās situācijas mēdz būt trokšņaini. Darbā ir izstrādāts algoritms, kas spēj izmantot inerciālā sensora datus un informāciju par mehānisko sistēmu, lai aprakstītu divu ķermeņu relatīvo orientāciju, neizmantojot magnētiskā lauka sensorus. Ir izveidota eksperimentālā sistēma, kur izstrādātais algoritms salīdzināts ar pieeju, kas lieto komerciālus inerciālo sensoru mezglus, kas izmanto magnētiskā lauka sensorus. Eksperimentos noteiktā algoritma kļūda ir 7.52o, BNO055…
Informe de la salud visual y ocular de los países que conforman la Red Epidemiológica Iberoamericana para la Salud Visual y Ocular (REISVO), 2009 y 2…
2015
A pesar de que se han hecho importantes progresos en el cuidado de la salud ocular, la prevalencia de la ceguera evitable sigue siendo inaceptablemente alta en muchos países y comunidades (OMS, 2009). La salud visual es un tema de la agenda política en algunos países; sin embargo, aún no se cuenta con un sistema de información que permita identificar la situación de morbilidad en salud visual en Iberoamérica, para poder priorizar y planificar la orientación de los servicios de atención en optometría y oftalmología. Para que existan planes de salud, deben establecerse líneas de base a través de un diagnóstico epidemiológico y de necesidades de la población; por esta razón, REISVO ha desarrol…
Cellular and Molecular Signatures of Oxidative Stress in Bronchial Epithelial Cell Models Injured by Cigarette Smoke Extract
2022
Exposure of the airways epithelium to environmental insults, including cigarette smoke, results in increased oxidative stress due to unbalance between oxidants and antioxidants in favor of oxidants. Oxidative stress is a feature of inflammation and promotes the progression of chronic lung diseases, including Chronic Obstructive Pulmonary Disease (COPD). Increased oxidative stress leads to exhaustion of antioxidant defenses, alterations in autophagy/mitophagy and cell survival regulatory mechanisms, thus promoting cell senescence. All these events are amplified by the increase of inflammation driven by oxidative stress. Several models of bronchial epithelial cells are used to study the molec…
The Land Surface Temperature Synergistic Processor in BEAM: A Prototype towards Sentinel-3
2016
Land Surface Temperature (LST) is one of the key parameters in the physics of land-surface processes on regional and global scales, combining the results of all surface-atmosphere interactions and energy fluxes between the surface and the atmosphere. With the advent of the European Space Agency (ESA) Sentinel 3 (S3) satellite, accurate LST retrieval methodologies are being developed by exploiting the synergy between the Ocean and Land Colour Instrument (OLCI) and the Sea and Land Surface Temperature Radiometer (SLSTR). In this paper we explain the implementation in the Basic ENVISAT Toolbox for (A)ATSR and MERIS (BEAM) and the use of one LST algorithm developed in the framework of the Syner…
Wireless energy and information transmission in FSO and RF-FSO links
2018
We propose and analyze a wireless energy and information transmission scheme in free-space optical (FSO) links. The results are presented for both quasi-static and fast-fading conditions. We derive closed-form expressions for throughput, outage probability, and optimal power allocation optimizing the system throughput/outage probability. Finally, we complement the FSO link with an additional radio frequency (RF) link to create a hybrid RF-FSO system and reduce the system outage probability. The results show that joint implementation of the RF and FSO links leads to considerable performance improvement, compared to the cases with only FSO-based communication.
Three-dimensional polarimetric computational integral imaging
2012
In this paper, we propose a novel 3D polarimetric computational integral imaging system by using polarization diversity of objects under natural illumination conditions. In the system, the measured Stokes polarization parameters are utilized to generate degree of polarization images of a 3D scene. Based on degree of polarization images and original 2D images, we utilize a modified computational reconstruction method to perform 3D polarimetric image reconstruction. The system may be used to detect or classify objects with distinct polarization signatures in 3D space. Experimental results also show the proposed system may mitigate the effect of occlusion in 3D reconstruction.
Extended View Angle Integral Imaging 3D Display using Smart Pseudoscopic-to-orthoscopic Conversion with Head Tracking
2016
We overview a head tracking integral imaging display using the smart pseudoscopic-to-orthoscopic conversion method. The crosstalk for a large viewing angle in integral imaging is eliminated by generating a new set of elemental images.
Head Tracking Three-Dimensional Integral Imaging Display Using Smart Pseudoscopic-to-Orthoscopic Conversion
2016
A novel head tracking three-dimensional (3D) integral imaging display is presented. By means of proper application of the smart pseudoscopic-to-orthoscopic conversion (SPOC) method, our display allows an extended viewing angle accommodated to the viewer's position which is obtained by a head/eye tracking system. Using the SPOC, new sets of elemental images are calculated and adapted to any specific viewing position. Additionally, the crosstalk which is typical in conventional integral imaging, is eliminated for a large viewing angle. By performing the rotation transformation in the simulated display, viewing a 3D scene with head rotation can be realized for robust display. Experimental resu…
Optimized integral imaging display by global pixel mapping
2006
Integral imaging systems are imaging devices that provide 3D images of 3D objects. When integral imaging systems work in their standard configuration the provided reconstructed images are pseudoscopic; that is, are reversed in depth. In this paper we present a technique for formation of real, undistorted, orthoscopic integral images by direct pickup. The technique is based on a global mapping of pixels of an elemental-images set. Simulated imaging experiments are presented.
3D integral imaging display by smart pseudoscopic-to-orthoscopic conversion (SPOC).
2010
Previously, we reported a digital technique for formation of real, non-distorted, orthoscopic integral images by direct pickup. However the technique was constrained to the case of symmetric image capture and display systems. Here, we report a more general algorithm which allows the pseudoscopic to orthoscopic transformation with full control over the display parameters so that one can generate a set of synthetic elemental images that suits the characteristics of the Integral-Imaging monitor and permits control over the depth and size of the reconstructed 3D scene.