171 research outputs found

    A system for beach video-monitoring: Beachkeeper plus

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    A suitable knowledge of coastal systems, of their morphodynamic characteristics and their response to storm events and man-made structures is essential for littoral conservation and management. Nowadays webcams represent a useful device to obtain information from beaches. Video-monitoring techniques are generally site specific and softwares working with any image acquisition system are rare. Therefore, this work aims at submitting theory and applications of an experimental video monitoring software: Beachkeeper plus, a freeware non-profit software, can be employed and redistributed without modifications. A license file is provided inside software package and in the user guide. Beachkeeper plus is based on Matlab ® and it can be used for the analysis of images and photos coming from any kind of acquisition system (webcams, digital cameras or images downloaded from internet), without any a-priori information or laboratory study of the acquisition system itself. Therefore, it could become a useful tool for beach planning. Through a simple guided interface, images can be analyzed by performing georeferentiation, rectification, averaging and variance. This software was initially operated in Pietra Ligure (Italy), using images from a tourist webcam, and in Mar del Plata (Argentina) using images from a digital camera. In both cases the reliability in different geomorphologic and morphodynamic conditions was confirmed by the good quality of obtained images after georeferentiation, rectification and averaging. © 2012 Elsevier Ltd.Fil: Brignone, Massimo. University of Genoa; ItaliaFil: Schiaffino, Chiara F.. University of Genoa; ItaliaFil: Isla, Federico Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Ferrari, Marco. University of Genoa; Itali

    Calibration of the JIG v1.2 for the SKA-TPM-ADU v1.6

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    The document describes how the JIG for SKA TPM ADU (Square Kilometer Array, Tile Processing Module, Analog to Digital Unit) board was calibrated and shows the results

    A Decision Support System Based on BI-RADS and Radiomic Classifiers to Reduce False Positive Breast Calcifications at Digital Breast Tomosynthesis: A Preliminary Study

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    Digital breast tomosynthesis (DBT) studies were introduced as a successful help for the detection of calcification, which can be a primary sign of cancer. Expert radiologists are able to detect suspicious calcifications in DBT, but a high number of calcifications with non-malignant diagnosis at biopsy have been reported (false positives, FP). In this study, a radiomic approach was developed and applied on DBT images with the aim to reduce the number of benign calcifications addressed to biopsy and to give the radiologists a helpful decision support system during their diagnostic activity. This allows personalizing patient management on the basis of personalized risk. For this purpose, 49 patients showing microcalcifications on DBT images were retrospectively included, classified by BI-RADS (Breast Imaging-Reporting and Data System) and analyzed. After segmentation of microcalcifications from DBT images, radiomic features were extracted. Features were then selected with respect to their stability within different segmentations and their repeatability in test–retest studies. Stable radiomic features were used to train, validate and test (nested 10-fold cross-validation) a preliminary machine learning radiomic classifier that, combined with BI-RADS classification, allowed a reduction in FP of a factor of 2 and an improvement in positive predictive value of 50%

    Radio frequency over fiber technology for SKA-low receiver

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    The signal reception chain is an essential element for achieving the square kilometer array-low (SKA-low) system requirements in terms of high sensitivity and dynamic range. The balance between gain, linearity, and low power consumption, as well as the cost, are fundamental parameters that influence the selection of the most suitable technology for SKA-low. Further factors, such as low self-generated radio frequency (RF) interference, high reliability, robustness under extreme environment, and last but not least, the distance between the antennas and the acquisition systems, have impacts on the selection for both architecture and receiver system design. The selected technology for the SKA-low RF signal transportation is RF-over-fiber systems, where the preamplified RF signal picked up by the antennas is carried via analogue modulation over optical fiber. The rationales behind the selection are reported, along with descriptions on the development of the receiver prototypes. The prototypes were deployed and installed on the demonstrator arrays at the selected SKA-low site in Western Australian. Particular attention has been put on the thermal characterization of the receiver system under the actual operating temperature on site, especially when both transmitting part and the optical medium are subjected to external ambient temperature variations. Performance issues encountered in the demonstrator arrays are also discussed along with some proposals for future activities

    Test-Driven Design of an Active Dual-Polarized Log-Periodic Antenna for the Square Kilometre Array

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    An active dual-polarized Log-Periodic antenna has been designed to meet the requirements of the low-frequency (50 - 350 MHz) radio telescope of the Square Kilometre Array (SKA). The integration of antenna and low noise amplifier has been conceived in order to achieve a high degree of testability. This aspect has been found to be crucial to obtain a smooth frequency response compatible with the SKA science cases. The design has also been driven by other factors such as the large-volume production (more than 130 000 antennas will be built) and the environmental conditions of the harsh Australian desert. A specific verification approach based on both wideband radiometric spectral and spatial measurements in relevant laboratory and in-situ conditions has been developed. Electromagnetic analyses and experimental results exhibit a very good agreement. In December 2019, this antenna was part of the reference solution for the System Critical Design Review of the SKA

    Design, synthesis, crystallization and biological evaluation of new symmetrical biscationic compounds as selective inhibitors of human Choline Kinase α1 (ChoKα1)

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    The authors gratefully acknowledge the ‘Consejería de Innovación, Ciencia y Empresa, Junta de Andalucía’ (Excellence Research Project: P07-CTS-03210), the ‘Diputación General de Aragón (B89)’ and the ‘Ministerio de Ciencia e Innovación’ (SAF2009-11955, BFU2010-19504 and CTQ2013-44367-C2-2-P) for the financial support, the award of grants from ‘Ministerio de Educación’ to P.R.-M. and S.S.-E. is gratefully acknowledged, and the ‘Centro de Servicios de Informática of the University of Granada (Spain) for the use of their computers and scientific software. G.V.,R.B., R.M. and G.B. We thanks also the Fondazione Cariparo by the “Progetto Ricerca Pediatrica”. We thank synchrotron radiation sources ALBA (Barcelona), and in particular the beamline XALOC. The research leading to these results has also received funding from the FP7 (2007–2013) under BIOSTRUCTX-7687.A novel family of compounds derivative of 1,1′-(((ethane-1,2-diylbis(oxy))bis(4,1-phenylene))bis(methylene))-bispyridinium or –bisquinolinium bromide (10a-l) containing a pair of oxygen atoms in the spacer of the linker between the biscationic moieties, were synthesized and evaluated as inhibitors of choline kinase against a panel of cancer-cell lines. The most promising compounds in this series were 1,1′-(((ethane-1,2-diylbis(oxy))bis(4,1-phenylene))bis(methylene))bis(4-(dimethylamino)pyridinium) bromide (10a) and 1,1′-(((ethane-1,2-diylbis(oxy))bis(4,1-phenylene))bis(methylene))-bis(7-chloro-4-(pyrrolidin-1-yl)quinolinium) bromide (10l), which inhibit human choline kinase (ChoKα1) with IC50 of 1.0 and 0.92 μM, respectively, in a range similar to that of the previously reported biscationic compounds MN58b and RSM932A. Our compounds show greater antiproliferative activities than do the reference compounds, with unprecedented values of GI50 in the nanomolar range for several of the cancer-cell lines assayed, and more importantly they present low toxicity in non-tumoral cell lines, suggesting a cancer-cell-selective antiproliferative activity. Docking studies predict that the compounds interact with the choline-binding site in agreement with the binding mode of most previously reported biscationic compounds. Moreover, the crystal structure of ChoKα1 with compound 10a reveals that this compound binds to the choline-binding site and mimics HC-3 binding mode as never before.Junta de Andalucía P07-CTS-03210Diputación General de Aragón (B89)Ministerio de Ciencia e Innovación (SAF2009-11955, BFU2010-19504, CTQ2013-44367-C2-2-P)Ministerio de EducaciónUniversity of Granada (Spain)Fondazione CariparoBIOSTRUCTX-7687 FP7 (2007–2013
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