49 research outputs found
Compact Hash Codes for Efficient Visual Descriptors Retrieval in Large Scale Databases
In this paper we present an efficient method for visual descriptors retrieval
based on compact hash codes computed using a multiple k-means assignment. The
method has been applied to the problem of approximate nearest neighbor (ANN)
search of local and global visual content descriptors, and it has been tested
on different datasets: three large scale public datasets of up to one billion
descriptors (BIGANN) and, supported by recent progress in convolutional neural
networks (CNNs), also on the CIFAR-10 and MNIST datasets. Experimental results
show that, despite its simplicity, the proposed method obtains a very high
performance that makes it superior to more complex state-of-the-art methods
Bloom Filters and Compact Hash Codes for Efficient and Distributed Image Retrieval
This paper presents a novel method for efficient image retrieval, based on a
simple and effective hashing of CNN features and the use of an indexing
structure based on Bloom filters. These filters are used as gatekeepers for the
database of image features, allowing to avoid to perform a query if the query
features are not stored in the database and speeding up the query process,
without affecting retrieval performance. Thanks to the limited memory
requirements the system is suitable for mobile applications and distributed
databases, associating each filter to a distributed portion of the database.
Experimental validation has been performed on three standard image retrieval
datasets, outperforming state-of-the-art hashing methods in terms of precision,
while the proposed indexing method obtains a speedup
Análisis dinámico de vigas compuestas laminadas de sección I. Consideración de la deformidad del alma
En el presente trabajo se desarrolla un modelo teórico y computacional de vigas de pared delgadas laminadas de sección I construidas con materiales compuestos, teniendo en cuenta la influencia que pueden provocar para el caso dinámico la consideración del efecto de corte e inercia rotatoria y la deformabilidad del alma fuera de su propio plano. Para este último efecto, se sigue el modelo desarrollado por Hughes y Ma para sus estudios de pandeo torsional de vigas tipo I monosimétricas de material isótropo bajo la acción de cargas puntuales. El modelo matemático puede ser aplicado tanto a vigas dematerial isótropo como compuesto. Se desarrolla un nuevo elemento finito codificado a través de una rutina implementada bajo el entorno MATHEMATICA versión 4.0 y se efectúa un análisis paramétrico de los diversos efectos contemplados.Fil: Vera, Carlos Alberto. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; ArgentinaFil: Cortínez, Víctor Hugo. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; ArgentinaFil: Ercoli, Liberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca; Argentina. Universidad Tecnológica Nacional. Facultad Regional Bahía Blanca. Grupo de Análisis de Sistemas Mecánicos; Argentin
Tracing the origin of the panda's thumb
© 2015, Springer-Verlag Berlin Heidelberg. We investigate the relative development of the carnivoran radial sesamoids to untangle the evolution of this iconic structure. In the pandas (both giant and red), this `false thumb¿ is known to perform a grasping role during bamboo feeding in both the red and giant pandas. An original locomotor role has been inferred for ailurids, but this remains to be ascertained for ursids. A large sample of radial sesamoids of Indarctos arctoides from the Miocene of Batallones-3 (Spain) indicates that this early ailuropodine bear displayed a relatively hypertrophied radial sesamoid, with a configuration more similar to that of the red panda and other carnivorans than to that of giant pandas. This false thumb is the first evidence of this feature in the Ursidae, which can be linked to a more herbivorous diet. Moreover, in the two extant pandas, the false thumb should not be interpreted as an anatomical convergence, but as an exaptive convergence regarding its use during the bamboo feeding, which changes the evolutionary view of this singular structure.This study was supported by the Spanish Ministerio de Economía y Competitividad (CGL2011-25754, CGL2011-28681 and RYC–2009–04533 to D.M.A.).
A.V. is a researcher in formation in the CSIC program JAE-PRE_CP2011 (CSIC program‘ Junta para la ampliación de estudios’), co-funded by the European Social Fund and has received funding from the European Union’s Seventh Framework Programme (FP7/2007–2013) under grant agreement no. 226506 (SYNTHESYS; SE-TAF-3637),Peer Reviewe
La creación de una cultura de colaboración competitiva de las PyMES
Fil: García, Domingo. Universidad Nacional de La Matanza; Argentina.Fil: Belic, Ana María. Universidad Nacional de La Matanza; Argentina.Fil: Ercoli, María Adela. Universidad Nacional de La Matanza; Argentina.Fil: Mallo, Liliana Mónica. Universidad Nacional de La Matanza; Argentina.Fil: Fernández, Luis Alberto. Universidad Nacional de La Matanza; Argentina.Fil: Tejedor Dipolito, Marta. Universidad Nacional de La Matanza; Argentina.Fil: Lopa, Olimpia Teresa. Universidad Nacional de La Matanza; Argentina.Fil: Pueyo, Hebert. Universidad Nacional de La Matanza; Argentina.Fil: Fernández, Diego Roberto. Universidad Nacional de La Matanza
Data-driven clustering of combined Functional Motor Disorders based on the Italian registry
Functional Motor Disorders (FMDs) represent nosological entities with no clear phenotypic characterization, especially in patients with multiple (combined FMDs) motor manifestations. A data-driven approach using cluster analysis of clinical data has been proposed as an analytic method to obtain non-hierarchical unbiased classifications. The study aimed to identify clinical subtypes of combined FMDs using a data-driven approach to overcome possible limits related to "a priori" classifications and clinical overlapping
Risk factors associated with adverse fetal outcomes in pregnancies affected by Coronavirus disease 2019 (COVID-19): a secondary analysis of the WAPM study on COVID-19.
Objectives To evaluate the strength of association between maternal and pregnancy characteristics and the risk of adverse perinatal outcomes in pregnancies with laboratory confirmed COVID-19. Methods Secondary analysis of a multinational, cohort study on all consecutive pregnant women with laboratory-confirmed COVID-19 from February 1, 2020 to April 30, 2020 from 73 centers from 22 different countries. A confirmed case of COVID-19 was defined as a positive result on real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay of nasal and pharyngeal swab specimens. The primary outcome was a composite adverse fetal outcome, defined as the presence of either abortion (pregnancy loss before 22 weeks of gestations), stillbirth (intrauterine fetal death after 22 weeks of gestation), neonatal death (death of a live-born infant within the first 28 days of life), and perinatal death (either stillbirth or neonatal death). Logistic regression analysis was performed to evaluate parameters independently associated with the primary outcome. Logistic regression was reported as odds ratio (OR) with 95% confidence interval (CI). Results Mean gestational age at diagnosis was 30.6+/-9.5 weeks, with 8.0% of women being diagnosed in the first, 22.2% in the second and 69.8% in the third trimester of pregnancy. There were six miscarriage (2.3%), six intrauterine device (IUD) (2.3) and 5 (2.0%) neonatal deaths, with an overall rate of perinatal death of 4.2% (11/265), thus resulting into 17 cases experiencing and 226 not experiencing composite adverse fetal outcome. Neither stillbirths nor neonatal deaths had congenital anomalies found at antenatal or postnatal evaluation. Furthermore, none of the cases experiencing IUD had signs of impending demise at arterial or venous Doppler. Neonatal deaths were all considered as prematurity-related adverse events. Of the 250 live-born neonates, one (0.4%) was found positive at RT-PCR pharyngeal swabs performed after delivery. The mother was tested positive during the third trimester of pregnancy. The newborn was asymptomatic and had negative RT-PCR test after 14 days of life. At logistic regression analysis, gestational age at diagnosis (OR: 0.85, 95% CI 0.8-0.9 per week increase; pPeer reviewe