A Random Greedy based Design Time Tool for AI Applications Component Placement and Resource Selection in Computing Continua

Artificial Intelligence (AI) and Deep Learning (DL) are pervasive today, with applications spanning from personal assistants to healthcare. Nowadays, the accelerated migration towards mobile computing and Internet of Things, where a huge amount of data is generated by widespread end devices, is determining the rise of the edge computing paradigm, where computing resources are distributed among devices with highly heterogeneous capacities. In this fragmented scenario, efficient component placement and resource allocation algorithms are crucial to orchestrate at best the computing continuum resources. In this paper, we propose a tool to effectively address the component placement problem for AI applications at design time. Through a randomized greedy algorithm, our approach identifies the placement of minimum cost providing performance guarantees across heterogeneous resources including edge devices, cloud GPU-based Virtual Machines and Function as a Service solutions. Finally, we compare the random greedy method with the HyperOpt framework and demonstrate that our proposed approach converges to a near-optimal solution much faster, especially in large scale systems

SPACE4AI-R: a Runtime Management Tool for AI Applications Component Placement and Resource Scaling in Computing Continua

The recent migration towards Internet of Things determined the rise of a Computing Continuum paradigm where Edge and Cloud resources coordinate to support the execution of Artificial Intelligence (AI) applications, becoming the foundation of use-cases spanning from predictive maintenance to machine vision and healthcare. This generates a fragmented scenario where computing and storage power are distributed among multiple devices with highly heterogeneous capacities. The runtime management of AI applications executed in the Computing Continuum is challenging, and requires ad-hoc solutions. We propose SPACE4AI-R, which combines Random Search and Stochastic Local Search algorithms to cope with workload fluctuations by identifying the minimum-cost reconfiguration of the initial production deployment, while providing performance guarantees across heterogeneous resources including Edge devices and servers, Cloud GPU-based Virtual Machines and Function as a Service solutions. Experimental results prove the efficacy of our tool, yielding up to 60% cost reductions against a static design-time placement, with a maximum execution time under 1.5s in the most complex scenarios

Classificação de imagens orbitais com auxílio da análise por componentes principais no município de Montenegro, RS, 2009.

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Potencialidade do uso de imagens orbitais para detecção de mudanças temporais: estudo de caso no município de Montenegro-RS, 1993 - 2008.

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On the Use of Reciprocal Filter against WiFi Packets for Passive Radar

This paper aims at a critical review of the signal processing scheme used in WiFi-based passive radar in order to limit its complexity and enhance its suitability for short range civilian applications. To this purpose the exploitation of a reciprocal filtering strategy is investigated as an alternative to conventional matched filtering at the range compression stage. Along with the well-known advantage of a remarkable sidelobes control capability for the resulting range-Doppler response, the use of a reciprocal filter is shown to provide additional benefits for the specific sensor subject of this study. Specifically, it allows to streamline the disturbance cancellation stage and to implement a unified signal processing architecture which is capable to handle the different modulation schemes typically adopted in WiFi transmissions. Appropriate adjustments are also proposed to the theoretical reciprocal filter in order to cope with the inherent loss in term of signal-to-noise power ratio. The effectiveness of the revised signal processing scheme encompassing the reciprocal filtering strategy is proved against both simulated and experimental datasets

Reducing the Computational Complexity of WiFi-Based Passive Radar Processing

WiFi-based passive radar is considered in this paper as an effective technology for short range monitoring applications. Aiming at limiting its complexity and enhancing its suitability for civilian applications, appropriate modifications are proposed to the signal processing scheme originally designed for such sensor. Specifically, we show that a simple inversion in the order of the main processing stages, namely clutter cancellation and range compression, allows to both reduce the number of floating-point operations and relax the requirements on the data management. Moreover, the use of a reciprocal filter in lieu of a matched filter to implement the range compression stage is proved to yield a further simplification in the resulting processing scheme along with additional benefits in terms of achievable performance in the considered application. The alternative processing schemes are compared in terms of computational burden and the effectiveness of the proposed cost-effective solutions is proved against experimental datasets

NaOCl and EDTA irrigating solutions for endodontics: SEM findings

Premolars roots of humans were manually instrumented with K-type files and irrigated with different solutions to evaluate the rate of cleaning of endodontic surface. Root canals irrigated with 0.9% saline solution or H2O2 (10 volumes) showed the presence of predentin and amorphous smear layer. Thick smear layer was always present on endodontic walls rinsed with 5% solution of NaOCl. Specimens treated with 0.2% solution of EDTA showed partially clean dentinal tubules orifices and remnants of a thin smear layer. Occasional uninstrumented areas of the same roots presented smear layer remnants and predentin with calcified bacteriae. The root canals irrigated with NaOCl and EDTA solutions alternated after each instrument showed at the dentin surface thick smear layer: only few dentinal tubules orifices were visible.Endodontic surface of root canals irrigated with NaOCl during instrumentation and finally rinsed with EDTA solutions showed the most homogeneous ultrastructural pictures: partially clean dentinal orifices were detectable in the whole canals.Les canaux de la racine dentaire des prémolaires humaines ont été instrumentés manuellement avec files K type et ensuite irrigués avec différentes solutions pour évaluer les conditions de netteté de la surface endodontique.Les canaux irrigués avec une solution saline à 0,9% ou de H2O2 (10 volumes) ont démontré la présence de prédentine ou d’une couche de tissu salie. Cette couche était toujours présente sur la paroi endodontique lavée avec une solution de NaOCl à 5%. Les exemplaires traités avec une solution de EDTA à 0,2% ont démontré une netteté partielle des orifices tubulaires dentinaires et seulement un mince résidu non propre. Les zones non instrumentées de la même racine présentaient au contraire des résidus et une prédentine avec nombreuses bactéries calcifiées. Les canaux irrigués avec une solution de NaOCl et EDTA alternée ont démontré la présence d’une épaisse couche non propre et la visualisation de quelques orifices tubulaires. La surface endodontique des canaux de la racine irriguée avec NaOCl pendant l’instrumentation et ensuite lavée avec EDTA a démontré les images ultrastructurales les plus homogènes: les orifices dentinaires partiellement nettoyés pouvait être visualisés sur toute la surface du canal

Lipid storage and autophagy in melanoma cancer cells

Cancer stem cells (CSC) represent a key cellular subpopulation controlling biological features such as cancer progression in all cancer types. By using melanospheres established from human melanoma patients, we compared less differentiated melanosphere-derived CSC to differentiating melanosphere-derived cells. Increased lipid uptake was found in melanosphere-derived CSC vs. differentiating melanosphere-derived cells, paralleled by strong expression of lipogenic factors Sterol Regulatory Element-Binding Protein-1 (SREBP-1) and Peroxisome Proliferator-Activated Receptor-γ (PPAR-γ). An inverse relation between lipid-storing phenotype and autophagy was also found, since microtubule-associated protein 1A/1B-Light Chain 3 (LC3) lipidation is reduced in melanosphere-derived CSC. To investigate upstream autophagy regulators, Phospho-AMP activated Protein Kinase (P-AMPK) and Phospho-mammalian Target of Rapamycin (P-mTOR) were analyzed; lower P-AMPK and higher P-mTOR expression in melanosphere-derived CSC were found, thus explaining, at least in part, their lower autophagic activity. In addition, co-localization of LC3-stained autophagosome spots and perilipin-stained lipid droplets was demonstrated mainly in differentiating melanosphere-derived cells, further supporting the role of autophagy in lipid droplets clearance. The present manuscript demonstrates an inverse relationship between lipid-storing phenotype and melanoma stem cells differentiation, providing novel indications involving autophagy in melanoma stem cells biology

OFDM based WiFi Passive Sensing: a reference-free non-coherent approach

WiFi based passive sensing is attracting considerable interest in the scientific community for both research and commercial purposes. In this work, we aim at taking a step forward in an endeavor to achieve good sensing capabilities employing compact, low-cost, and stand-alone WiFi sensors. To this end, we resort to a reference-free non-coherent signal processing scheme, where the presence of a moving target echo is sought by detecting the amplitude modulation that it produces on the direct signal transmitted from the WiFi access point. We first validate the proposed strategy against simulated data, identifying advantages and limitations. Then, we apply the conceived solution on experimental data collected in a small outdoor area with the purpose of detecting a small cooperative drone