Data Fusion BAUE Estimation of a deterministic vector, applications to image noise and blur reduction

In this work we conceive centralized data fusion as a deterministic parameter estimation problem. Two different criterions are compared: best affine unbiased fusion rule (BAUE), and Maximum Likelihood for Gaussian measurement noise. Estimates are described in terms of their covariance matrices, the Cramer-Rao lower bound and simulations. The developed fusion rules are suited to two different image fusion cases: noise reduction under differently exposed images, and blur reduction based on lens response knowledge.Sociedad Argentina de Informática e Investigación Operativ

Robust methods for background extraction in video

In this paper a framework is presented to automatically extract a sequence of images of the background of a scene from a shaky film. That is, the input video sequence may have local and global motion but the output video must contain exclusively the static background scene. Applying robust procedures to this end is one of the main goals of this work, since the aim is to get a procedure not only resistant to low scale noise but to occasional high scale noise. The median is used as an estimate of the background, the median absolute deviation (MAD) is used to establish a threshold to locate foreground and M-estimation for regression is used to stabilize the video sequence.Sociedad Argentina de Informática e Investigación Operativ

Cache Sharing Administration for Performance Fairness using D3C Miss Classification in Chip Multi-Processors

This work presents a study of fairness in cache sharing between processes in a chip multiprocessor (CMP). We propose a new algorithm that uses a metric based on the D3C miss classification and LRU Stack Distance, to measure the fairness in the administration of the resources to achieve an increase of the global IPC of all executed processes. Shared cache miss rate, IPC and bandwidth metrics were considered to analyze the simulation results obtained using three test sets. The obtained results showed that the proposed dynamic management policy compared to Capitalist management policy, has a lower global miss rate in shared cache and lower bandwidth usage for each test set studied and fulfills its objective of managing the shared cache space for every process while improving the overall IPC.Sociedad Argentina de Informática e Investigación Operativ

A Modular Workflow to Dynamically Instrument and Treat Information in Multi-Process Environments

This paper presents a workflow in order to generate and collect execution information in multi-process environments, which are suitable for simulating and studying private and shared cache organizations. We have developed a main tool that makes dynamic instrumentation with PIN, a controller to administrate the execution of processes and three workflow application modules to generate programs traces, simulate cache memories and manage the execution of several programs in parallel.Sociedad Argentina de Informática e Investigación Operativ

Virological rebound in human immunodeficiency virus-infected patients with or without residual viraemia: results from an extended follow-up

AbstractHuman immunodeficiency virus (HIV) -infected patients with HIV RNA loads of < 50 copies/mL were followed-up for a median (interquartile range) of 30.8 (11.7–32.9) months to study the effect of residual viraemia (RV) on virological rebound (VR). At baseline, 446 (60.3%) patients had undetectable HIV RNA (group A) and 293 (39.7%) had RV (1–49 HIV RNA copies/mL, group B) by kinetic PCR. VR occurred in 4 (0.9%) patients in group A and in 12 (4.1%) patients in group B (p 0.007). Time to VR was shorter among patients of group B (Log-rank test: p 0.003). However, the proportion of VR was extremely low also among patients with RV

Emissivity measurements at room temperature on polymeric and inorganic samples

Abstract An evaluation of the emissivity of polymeric and inorganic materials has been carried out in the spectral range 8-121J.m using a direct technique. For polymeric samples the study focused on the dependence on the doping level. In the case of the inorganic samples measurements were aimed at the evaluation of the emissivity variations with the temperature Furthermore the effects on the emissivity of temperature differences between the sample and the background on the emissivity evaluation have been studied

On the source of the late-time infrared luminosity of SN 1998S and other type II supernovae

We present late-time near-infrared (NIR) and optical observations of the type IIn SN 1998S. The NIR photometry spans 333-1242 days after explosion, while the NIR and optical spectra cover 333-1191 days and 305-1093 days respectively. The NIR photometry extends to the M'-band (4.7 mu), making SN 1998S only the second ever supernova for which such a long IR wavelength has been detected. The shape and evolution of the H alpha and HeI 1.083 mu line profiles indicate a powerful interaction with a progenitor wind, as well as providing evidence of dust condensation within the ejecta. The latest optical spectrum suggests that the wind had been flowing for at least 430 years. The intensity and rise of the HK continuum towards longer wavelengths together with the relatively bright L' and M' magnitudes shows that the NIR emission was due to hot dust newly-formed in supernovae may provide the ejecta and/or pre-existing dust in the progenitor circumstellar medium (CSM). [ABRIDGED] Possible origins for the NIR emission are considered. Significant radioactive heating of ejecta dust is ruled out, as is shock/X-ray-precursor heating of CSM dust. More plausible sources are (a) an IR-echo from CSM dust driven by the UV/optical peak luminosity, and (b) emission from newly-condensed dust which formed within a cool, dense shell produced by the ejecta shock/CSM interaction. We argue that the evidence favours the condensing dust hypothesis, although an IR-echo is not ruled out. Within the condensing-dust scenario, the IR luminosity indicates the presence of at least 0.001 solar masses of dust in the ejecta, and probably considerably more. Finally, we show that the late-time intrinsic (K-L') evolution of type II supernovae may provide a useful tool for determining the presence or absence of a massive CSM around their progenitor stars.Comment: 23 pages, 15 figures, to be published in MNRA

High-resolution mapping of glacier surface features. The UAV survey of the Forni Glacier (Stelvio National Park, Italy)

Fast, reliable and accurate methods for glacier mapping are necessary for understanding glacier dynamics and evolution and assessing their response to climate change. Conventional semi-automatic approaches are based on medium-resolution satellite images, but their use can cause significant loss of accuracy when analyzing small glaciers, which are predominant in the Alps. In this paper, we present a semi-automatic segmentation approach based on very high-resolution visible RGB images acquired from a UAV (Unmanned Aerial Vehicle) survey of the Fomi Glacier, in the Italian Alps, using an off-the-shelf digital camera. The method has the ability to map large-scale morphological features, i.e. bare ice and medial moraines, with better accuracy than methods relying on medium-resolution satellite imagery, with only slight misclassification at the margins. By using segmentation, we also mapped small-scale morphologies not discernible on satellite images, including epiglacial lakes and snow patches, in a semi-automatic way. On a small portion of the eastern ablation tongue, featuring homogeneous illumination conditions, we also investigated in finer detail the occurrence of fine and sparse debris and tested a texture filter technique for mapping crevasses, which showed promising results. Our analyses confirm that the glacier is undergoing intense dynamic processes, including darkening of the ablation tongue and increased surface instability, and show the potential of UAVs to revolutionize glaciological studies. We suggest that by using a combination of different payloads, mapping of glacier features via UAVs could reach high levels of accuracy and speed, making them useful tools for glacier inventories and geomorphological maps