1,370 research outputs found
Early Paleogene climate at mid latitude in South America: mineralogical and paleobotanical proxies from continental sequences in Golfo San Jorge basin (Patagonia, Argentina)
The Paleocene-Eocene boundary was a period of transient and intense global warming that had a deep effect on middle and high latitude plant groups. Nevertheless, only scarce early Paleogene paleoclimatic records are known from the South American continental sequences deposited at these latitudes. In this contribution clay mineralogy and paleobotanical analyses (fossil woods and phytoliths) were used as paleoclimate proxies from the lower and middle parts of the Río Chico Group (Golfo San Jorge basin, Patagonia, Argentina). These new data may enable to understand the changing climatic conditions during part of the Paleocene-Eocene transition. In this setting, three clay mineral assemblages were identified: S1 assemblage (smectite) dominates the Peñas Coloradas Formation; S2 assemblage (smectite>kaolinite) occurs in the stratigraphic transition to the Las Flores Formation; and S3 assemblage (kaolinite>smectite) dominates the Las Flores Formation. These trend of change in the detrital clay mineral composition is interpreted as resulting mainly from the changing paleoclimatic conditions that shifted from seasonal warm temperate to tropical affecting the same source area lithology. Moreover, the paleobotanical data suggest that the Early Paleogene vegetation in the Golfo San Jorge basin underwent significant composition and diversity changes, ranging from mixed temperate - subtropical forest to mixed subtropical - tropical, humid forest. The integrated analysis of the clay mineral composition and the palaeobotanical assemblages suggests that, in central Argentinean Patagonia, the Paleocene-Eocene climate changed from temperate warm, humid and highly seasonal precipitation conditions to subtropical-tropical, more continuous year-round rainfall conditions
Real-Time Siamese Multiple Object Tracker with Enhanced Proposals
Maintaining the identity of multiple objects in real-time video is a
challenging task, as it is not always feasible to run a detector on every
frame. Thus, motion estimation systems are often employed, which either do not
scale well with the number of targets or produce features with limited semantic
information. To solve the aforementioned problems and allow the tracking of
dozens of arbitrary objects in real-time, we propose SiamMOTION. SiamMOTION
includes a novel proposal engine that produces quality features through an
attention mechanism and a region-of-interest extractor fed by an inertia module
and powered by a feature pyramid network. Finally, the extracted tensors enter
a comparison head that efficiently matches pairs of exemplars and search areas,
generating quality predictions via a pairwise depthwise region proposal network
and a multi-object penalization module. SiamMOTION has been validated on five
public benchmarks, achieving leading performance against current
state-of-the-art trackers. Code available at:
https://github.com/lorenzovaquero/SiamMOTIONComment: Accepted at Pattern Recognition. Code available at
https://github.com/lorenzovaquero/SiamMOTIO
CMOS-3D smart imager architectures for feature detection
This paper reports a multi-layered smart image sensor architecture for feature extraction based on detection of interest points. The architecture is conceived for 3-D integrated circuit technologies consisting of two layers (tiers) plus memory. The top tier includes sensing and processing circuitry aimed to perform Gaussian filtering and generate Gaussian pyramids in fully concurrent way. The circuitry in this tier operates in mixed-signal domain. It embeds in-pixel correlated double sampling, a switched-capacitor network for Gaussian pyramid generation, analog memories and a comparator for in-pixel analog-to-digital conversion. This tier can be further split into two for improved resolution; one containing the sensors and another containing a capacitor per sensor plus the mixed-signal processing circuitry. Regarding the bottom tier, it embeds digital circuitry entitled for the calculation of Harris, Hessian, and difference-of-Gaussian detectors. The overall system can hence be configured by the user to detect interest points by using the algorithm out of these three better suited to practical applications. The paper describes the different kind of algorithms featured and the circuitry employed at top and bottom tiers. The Gaussian pyramid is implemented with a switched-capacitor network in less than 50 μs, outperforming more conventional solutions.Xunta de Galicia 10PXIB206037PRMinisterio de Ciencia e Innovación TEC2009-12686, IPT-2011-1625-430000Office of Naval Research N00014111031
Cultural Democracy, Cultural Equity, and Cultural Policy : Perspectives from the UK and USA
Peer reviewedPublisher PD
Paleoecology and paleoenvironments of Podocarp trees in the Ameghino Petrified forest (Golfo San Jorge Basin, Patagonia, Argentina): constraints for Early Paleogene paleoclimate
During the Early Paleocene (Danian), Central Patagonia had a warm-temperate climate and was dominated by evergreen coniferous forests. Abundant permineralized conifer woods along with some dicot and palm leaf compressions were found in the Ameghino Petrified Forest, and provide evidence of this type of flora. All the permineralized wood and large trunks recovered were assigned to the species Podocarpoxylon mazzonii. An estimated tree height of 17-29m was calculated on the basis of diameter measurements. Based on 14 ring sequences, with a total of 169 rings, the mean ring width and Mean Sensitivity (MS) were 1.23 and 0.19mm respectively. The growth rings are moderately wide, extremely uniform and complacent, indicating that the environment was favourable and constant, and lacked significant stress factors limiting tree growth. Following the quantitative analysis for conifers outlined by Falcon-Lang, the growth ring anatomy of the Podocarpoxylon mazzonii suggests that these trees had an evergreen habit. The combination of the fossil flora, growth ring, and sedimentological analyses suggest that this mostly evergreen coniferous forest developed under warm-temperate conditions and without limiting factors
Analisi esplorativa della statuina neolitica di Vicofertile
La statuina neolitica femminile rinvenuta in una sepoltura a Vicofertile risulta prodotta localmente (analoga per composizione alle altre ceramiche dell'area parmense) e plasmata in tre parti successivamente assemblat
Depth Estimation and Image Restoration by Deep Learning from Defocused Images
Monocular depth estimation and image deblurring are two fundamental tasks in
computer vision, given their crucial role in understanding 3D scenes.
Performing any of them by relying on a single image is an ill-posed problem.
The recent advances in the field of Deep Convolutional Neural Networks (DNNs)
have revolutionized many tasks in computer vision, including depth estimation
and image deblurring. When it comes to using defocused images, the depth
estimation and the recovery of the All-in-Focus (Aif) image become related
problems due to defocus physics. Despite this, most of the existing models
treat them separately. There are, however, recent models that solve these
problems simultaneously by concatenating two networks in a sequence to first
estimate the depth or defocus map and then reconstruct the focused image based
on it. We propose a DNN that solves the depth estimation and image deblurring
in parallel. Our Two-headed Depth Estimation and Deblurring Network (2HDED:NET)
extends a conventional Depth from Defocus (DFD) networks with a deblurring
branch that shares the same encoder as the depth branch. The proposed method
has been successfully tested on two benchmarks, one for indoor and the other
for outdoor scenes: NYU-v2 and Make3D. Extensive experiments with 2HDED:NET on
these benchmarks have demonstrated superior or close performances to those of
the state-of-the-art models for depth estimation and image deblurring
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