52 research outputs found

    An Efficient Pipeline Wavefront Phase Recovery for the CAFADIS Camera for Extremely Large Telescopes

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    In this paper we show a fast, specialized hardware implementation of the wavefront phase recovery algorithm using the CAFADIS camera. The CAFADIS camera is a new plenoptic sensor patented by the Universidad de La Laguna (Canary Islands, Spain): international patent PCT/ES2007/000046 (WIPO publication number WO/2007/082975). It can simultaneously measure the wavefront phase and the distance to the light source in a real-time process. The pipeline algorithm is implemented using Field Programmable Gate Arrays (FPGA). These devices present architecture capable of handling the sensor output stream using a massively parallel approach and they are efficient enough to resolve several Adaptive Optics (AO) problems in Extremely Large Telescopes (ELTs) in terms of processing time requirements. The FPGA implementation of the wavefront phase recovery algorithm using the CAFADIS camera is based on the very fast computation of two dimensional fast Fourier Transforms (FFTs). Thus we have carried out a comparison between our very novel FPGA 2D-FFTa and other implementations

    Design of Belief Propagation Based on FPGA for the Multistereo CAFADIS Camera

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    In this paper we describe a fast, specialized hardware implementation of the belief propagation algorithm for the CAFADIS camera, a new plenoptic sensor patented by the University of La Laguna. This camera captures the lightfield of the scene and can be used to find out at which depth each pixel is in focus. The algorithm has been designed for FPGA devices using VHDL. We propose a parallel and pipeline architecture to implement the algorithm without external memory. Although the BRAM resources of the device increase considerably, we can maintain real-time restrictions by using extremely high-performance signal processing capability through parallelism and by accessing several memories simultaneously. The quantifying results with 16 bit precision have shown that performances are really close to the original Matlab programmed algorithm

    A hybrid legged-wheeled obstacle avoidance strategy for service operations

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    Hybrid legged-wheeled robots are gaining interest in various service applications, like surveillance or inspection in hospitals. The autonomy of these robots is not only related to their power consumption, it mostly refers to their capability to safely move in complex partially structured environments. This paper proposes to investigate the combination of different moving strategies and sensors to enhance the adaptability and autonomy of a hybrid hexapod robot in specific environments shared with humans. Namely, this paper proposes a locomotion strategy that combines leg motions and Mecanum omniwheels with multiple sensory feedbacks to achieve safe obstacle avoidance during a service operation. Several experimental tests are carried out by using Cassino Hexapod III in combination with sonar, IMU and Lidar sensors at IRCCS Neuromed site in Pozzilli. Experimental results show the effectiveness of the proposed operation strategy with Cassino Hexapod III to avoid multiple obstacles

    Iahris: New Software to Assess Hydrologic Alteration

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    Indicators of Hidrologic Alteration in RIverS (IAHRIS) is a software designed to fulfill: 1. Parameters for the characterization of the natural or regulated flow regime, in a section of the river. These parameters evaluate those aspects of the flow regime with the highest environmental meaning (magnitude, variability, seasonality and duration). Their definition has given priority to the consideration of the singular characteristics of the Mediterranean regimes. 2. If the user enters data of the natural flow regime and data for any other flow regime in the same section or reach (altered regime, environmental regime, management scenario, …) the software calculates, furthermore, a set of indicators that assess the degree of hydrologic alteration in comparison with the natural regime. These indicators of alteration have been defined attending to the CIS-WFD recommendations for the Ecological Quality Ratios. The software requires, at least, 15 entire years with data (daily average flows and/or monthly volumes). The type of data entered in IAHRIS determines, directly, the results accomplished. In particular, they depend on the data periodicity –daily or monthly-, and the simultaneous character of the data associated to the natural and the altered flow regimes. IAHRIS is free software, available at the website of the Spanish Ministry of the Environment

    Hernia atípica de la región inguinal: comunicación de un caso

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    ResumenIntroducciónLas hernias periinguinales, parainguinales y spigelianas bajas son hernias que pertenecen al grupo de las hernias ventrolaterales, también llamadas suprainguinales.Caso clínicoVarón de 32 años con tumoración en región inguinal derecha. Encontramos una hernia periinguinal de 1.5cm, a 1.5cm por arriba del anillo profundo. Se realizó cierre primario del defecto. Además se visualizó una hernia indirecta de 7.5×2cm. Se efectuó resección del saco, ligadura alta y técnica de Lichtenstein.DiscusiónDada la rareza de las hernias periinguinales, su clasificación, diagnóstico y tratamiento continúan en debate.AbstractIntroductionPeri-inguinal, para-inguinal and low spigelian hernias belong to the group of ventrolateral hernias, also called suprainguinal hernias.Case report32-year-old male with a mass in the right inguinal region; we found a peri-inguinal hernia defect of 1.5 centimeters to 1.5 centimeters above the deep ring. We developed primary closure of the defect, plus indirect hernia of 7.5 ×2 centimeters performing resection of the sac, high ligation and Lichtenstein technique.DiscussionGiven the rarity of peri-inguinal hernias, their classification, diagnosis and management continues to be debated

    Does empirically derived classification of individuals with subjective cognitive complaints predict dementia?

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    Background: Early identification of mild cognitive impairment (MCI) in people reporting subjective cognitive complaints (SCC) and the study of progression of cognitive decline are important issues in dementia research. This paper examines whether empirically derived procedures predict progression from MCI to dementia. (2) Methods: At baseline, 192 participants with SCC were diagnosed according to clinical criteria as cognitively unimpaired (70), single-domain amnestic MCI (65), multiple-domain amnestic MCI (33) and multiple-domain non-amnestic MCI (24). A two-stage hierarchical cluster analysis was performed for empirical classification. Categorical regression analysis was then used to assess the predictive value of the clusters obtained. Participants were re-assessed after 36 months. (3) Results: Participants were grouped into four empirically derived clusters: Cluster 1, similar to multiple-domain amnestic MCI; Cluster 2, characterized by subjective cognitive decline (SCD) but with low scores in language and working memory; Cluster 3, with specific deterioration in episodic memory, similar to single-domain amnestic MCI; and Cluster 4, with SCD but with scores above the mean in all domains. The majority of participants who progressed to dementia were included in Cluster 1. (4) Conclusions: Cluster analysis differentiated between MCI and SCD in a sample of people with SCC and empirical criteria were more closely associated with progression to dementia than standard criteria.This work was financially supported by the Spanish Directorate General of Scientific and Technical Research (Project PSI2014- 55316-C3-1-R) and by the Galician Government (Consellería de Cultura, Educación e Ordenación Universitaria; axudas para a consolidación e Estruturación de unidades de investigación competitivas do Sistema universitario de Galicia; GRC (GI-1807-USC); Ref: ED431-2017/27) through FEDER fundsS

    ECG study in practical labs for biomedical engineering training

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    Non-invasive biomedical measurements are one of the most important technological contributions whitin the biomedical engineering field. On this paper, a dual laboratory session student oriented is designed to simulate and implement a cardial signal monitor. During the first session, ORCAD PSpice software is used to simulate the whole process. The students can acquire knowledge on the process by configuring and running both the instrumentation amplifier and a passive filter to improve the signal quality. The second session requires from the student basic laboratory skills to use a specific printed circuit board (PCB) to measure its very own cardiac potential. As a result, from this session, the student can visualize the ECG signal acquired directly on the laboratory oscilloscope

    FPGA-Based Smart Sensor for Online Displacement Measurements Using a Heterodyne Interferometer

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    The measurement of small displacements on the nanometric scale demands metrological systems of high accuracy and precision. In this context, interferometer-based displacement measurements have become the main tools used for traceable dimensional metrology. The different industrial applications in which small displacement measurements are employed requires the use of online measurements, high speed processes, open architecture control systems, as well as good adaptability to specific process conditions. The main contribution of this work is the development of a smart sensor for large displacement measurement based on phase measurement which achieves high accuracy and resolution, designed to be used with a commercial heterodyne interferometer. The system is based on a low-cost Field Programmable Gate Array (FPGA) allowing the integration of several functions in a single portable device. This system is optimal for high speed applications where online measurement is needed and the reconfigurability feature allows the addition of different modules for error compensation, as might be required by a specific application

    SPGCam: A specifically tailored camera for solar observations

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Designing a new astronomical instrument typically challenges the available cameras on the market. In many cases, no camera can fulfill the requirements of the instrument in terms of photon budget, speed, and even interfaces with the rest of the instrument. In this situation, the only options are to either downgrade the performance of the instrument or design new cameras from scratch, provided it is possible to identify a compliant detector. The latter is the case of the SPGCams, the cameras developed to be used with the Tunable Magnetograph (TuMag) and the Sunrise Chromospheric Infrared spectroPolarimeter (SCIP) for the Sunrise iii mission. SPGCams have been designed, developed, and built entirely in-house by the Solar Physics Group (SPG) at the Instituto de Astrofísica de Andalucía (IAA-CSIC). We report here on the scientific rationale and system engineering requirements set by the two instruments that drove the development, as well as on the technical details and trade-offs used to fulfill the specifications. The cameras were fully verified before the flight, and results from the assembly and verification campaign are presented as well. SPGCams share the design, although some parametric features differentiate the visible cameras (for TuMag) and the IR ones (for SCIP). Even though they were specifically developed for the Sunrise iii mission, the robust and careful design makes them suitable for different applications in other astronomical instruments. © 2023 Orozco Suárez, Álvarez García, López Jiménez, Balaguer Jiménez, Hernández Expósito, Labrousse, Bailén, Bustamante Díaz, Bailón Martínez, Aparicio del Moral, Morales Fernández, Sánchez Gómez, Tobaruela Abarca, Moreno Mantas, Ramos Más, Pérez Grande, Piqueras Carreño, Katsukawa, Kubo, Kawabata, Oba, Rodríguez Valido, Magdaleno Castelló and Del Toro Iniesta.This work was funded by the Spanish MCIN/AEI, under projects RTI 2018-096886-B-C5, PID 2021-125325OB-C5, and PCI 2022-135009-2, and co-funded by European FEDER funds, “A way of making Europe,” under grants CEX 2021-001131-S and 10.13039/501100011033.Peer reviewe
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