Search results for "Filters"

Using Visual Saliency for Object Tracking with Particle Filters

2010

International audience; This paper presents a robust tracking method based on the integration of visual saliency information into the particle filter framework. While particle filter has been successfully used for tracking non-rigid objects, it shows poor performances in the presence of large illumination variation, occlusions and when the target object and background have similar color distributions. We show that considering saliency information significantly improves the performance of particle filter based tracking. In particular, the proposed method is robust against occlusion and large illumination variation while requiring a reduced number of particles. Experimental results demonstrate th…

The importance of dead seagrass (Posidonia oceanica)matte as a biogeochemical sink

2022

We assessed the potential of dead seagrass Posidonia oceanica matte to act as a biogeochemical sink and provide a coherent archive of environmental change in a degraded area of the Mediterranean Sea (Augusta Bay, Italy). Change in sediment properties (dry bulk density, grain size), concentration of elements (Corg, Cinorg, N, Hg) and stable isotope ratios (δ13C, δ 15N) with sediment depth were measured in dead P. oceanica matte and unvegetated (bare) sediments in the polluted area, and an adjacent P. oceanica meadow. Principal Component Analysis (PCA) revealed a clear clustering by habitat, which explained 72% of variability in our samples and was driven mainly by the accumulation of N and H…

Filters design and characterization for LAD instrument onboard eXTP

2022

Copyright 2022 Society of Photo‑Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this publication for a fee or for commercial purposes, and modification of the contents of the publication are prohibited. The LAD (Large Area Detector) instrument, onboard the Sino-European mission eXTP (enhanced X-ray Timing and Polarimetry), will perform single-photon, high-resolution timing and energy measurements, in the energy range 2–30 keV, with a large collecting area. Its silicon drift detectors need shielding from NIR/Vis/UV light by astrophysical sources and the bright Ea…

Digital Device Usage Time and Ocular Symptoms during COVID-19 Pandemic

2021

Bakalaura darbs ir uzrakstīts angļu valodā uz 25 lappusēm. Tas satur 10 attēlus, 6 tabulas un 22 atsauces uz literatūras avotiem. Šī pētījuma galvenais mērķis bija novērtēt kā digitālo ierīču lietošanas izmaiņas ikdienā pirms Covid-19 pandēmijas un pandēmijas laikā Itālijā ietekmē acu nogurumu. Digitālo ierīču ietekme uz acīm tika novērtēta, apkopojot pētījuma dalībnieku atbildes uz anketas jautājumiem. Digitālo ierīču izmantošana mūsdienās ir plaši izplatīta, tās ir jāizmanto, bet ievērojot nepieciešamos piesardzības pasākumus, lai neradītu traucējumus redzes un psihiskajā sistēmās.

Sintonikas ietekme uz miopiju

2017

MĒRĶIS: noteikt sintonikas fototerapijas efektivitāti jauniešiem ar vidējās pakāpes miopiju līdz 3,0D vai nekoriģēto sākotnējo miopiju. METODE: 10 miopi vecumā no 8 līdz 17 gadi. Tika izmantotāss redzes asuma, miopijas pakāpes, akomodācijas amplitūdas, acs zīlītes αω reakcijas un redzes lauka noteikšanas testi. Pēc sākotnējās pārbaudēs dalībnieki tika pakļauti 15 sintonikas seansiem. REZULTĀTI: pēc sintonikas pielietošanas statistiski nozīmīgi uzlabojas akomodācijas amplitūda, redzes asums, acs zīlītes reakcijas - αω un redzes lauks. Tika novērots miopijas samazinājums3 dalībniekiem ar sākotnējo miopiju un nozīmīga uzlabošanas parējiem 4 dalībniekiem. SECINĀJUMI: Statistiski nozīmīgi rezult…

An Efficient Implementation of Parallel Parametric HRTF Models for Binaural Sound Synthesis in Mobile Multimedia

2020

The extended use of mobile multimedia devices in applications like gaming, 3D video and audio reproduction, immersive teleconferencing, or virtual and augmented reality, is demanding efficient algorithms and methodologies. All these applications require real-time spatial audio engines with the capability of dealing with intensive signal processing operations while facing a number of constraints related to computational cost, latency and energy consumption. Most mobile multimedia devices include a Graphics Processing Unit (GPU) that is primarily used to accelerate video processing tasks, providing high computational capabilities due to its inherent parallel architecture. This paper describes…

Sistema di posizionamento geo-spaziale cooperativo operante con sistemi di navigazione globale satellitare e reti di telecomunicazione wireless, rela…

2010

Diagnosis and Treatment of Lower Extremity Venous Thromboembolism

2020

Importance: Incidence rates for lower extremity deep vein thrombosis (DVT) range from 88 to 112 per 100 000 person-years and increase with age. Rates of recurrent VTE range from 20% to 36% during the 10 years after an initial event.Observations: PubMed and Cochrane databases were searched for English-language studies published from January 2015 through June 2020 for randomized clinical trials, meta-analyses, systematic reviews, and observational studies. Risk factors for venous thromboembolism (VTE), such as older age, malignancy (cumulative incidence of 7.4% after a median of 19 months), inflammatory disorders (VTE risk is 4.7% in patients with rheumatoid arthritis and 2.5% in those withou…

Clinical experience with retrievable vena cava filters: results of a prospective observational multicenter study

2005

Summary. Background: Retrievable inferior vena cava (IVC) filters offer the attractive possibility to be definitive or to be removed when they become unnecessary. Objective: The purpose of this study was to evaluate the efficacy and the likelihood to remove the retrievable IVC filter ALN. Methods: A total of 30 patients (13 males and 17 females, mean age 57 ± 15 years) underwent placement of ALN filters. Indications for implantation were acute venous thromboembolism (VTE) with a contraindication to anticoagulation in 26 cases (86%), primary prophylaxis after major trauma in two cases (7%) or before surgery in two patients with very high thromboembolic risk (7%). Results: The filter was succ…

Morphology and composition of particulate matter in the air of urban area

2019

Zanieczyszczenie powietrza przez pyl zawieszony (PM) staje się w ostatnich latach coraz bardziej znaczące. Stwierdzono, że unoszące się w powietrzu cząsteczki niosą różne niekorzystne skutki dla środowiska i zdrowia ludzkiego. Aby poszerzyć wiedzę na temat takich zanieczyszczeń, pożądana jest szczegółowa charakterystyka rozmiarów, morfologii i składu chemicznego poszczególnych cząstek zawieszonych w po- wietrzu. W prezentowanych badaniach mikrocząsteczki powietrza zostały pobrane z filtrów taśmowych z włókna szklanego, które są powszechnie stosowane w analizatorach cząstek stałych MP101M. Próbki zostały zebrane w Kutnej Horze (Republika Czeska), były badane metodami skaningowej mikroskopii …