14 research outputs found

    Relative pose determination algorithm for space on-orbit close range autonomous operation using LiDAR

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    Non cooperative on-orbit operations, such as rendezvous, docking or berthing operations, have become more relevant, mainly due to the necessity of expanding mission lifetimes, the increase of space debris and the reduction of human dependency. In order to automate these operations, the relative pose calculation between the target and the chaser must be determined autonomously. In recent years, LiDAR sensors have been introduced for this problem, achieving good accuracies. The critical part of this operation is the first relative pose calculation, since there is no previous information about the attitude of the target. In this work, a methodology to carry out this first relative pose calculation using LiDAR sensors is presented. A template matching algorithm has been developed, which uses the 3D model of the target to calculate the relative pose of the target regarding the LiDAR sensor. Three different study cases, with different distances and rotations, have been simulated in order to validate the algorithm, reaching an average error of 0.0383m

    A benchmarking of commercial small fixed-wing electric UAVs and RGB cameras for photogrammetry monitoring in intertidal multi-regions

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    Small fixed-wing electric Unmanned Aerial Vehicles (UAVs) are perfect candidates to perform tasks in wide areas, such as photogrammetry, surveillance, monitoring, or search and rescue, among others. They are easy to transport and assemble, have much greater range and autonomy, and reach higher speeds than rotatory-wing UAVs. Aiming to contribute towards their future implementation, the objective of this article is to benchmark commercial, small, fixed-wing, electric UAVs and compatible RGB cameras to find the best combination for photogrammetry and data acquisition of mussel seeds and goose barnacles in a multi-region intertidal zone of the south coast of Galicia (NW of Spain). To compare all the options, a Coverage Path Planning (CPP) algorithm enhanced for fixed-wing UAVs to cover long areas with sharp corners was posed, followed by a Traveling Salesman Problem (TSP) to find the best route between regions. Results show that two options stand out from the rest: the Delair DT26 Open Payload with a PhaseOne iXM-100 camera (shortest path, minimum number of pictures and turns) and the Heliplane LRS 340 PRO with the Sony Alpha 7R IV sensor, finishing the task in the minimum time.Agencia Estatal de Investigación | Ref. PID2021-125060OB-I00Agencia Estatal de Investigación | Ref. TED2021-129756B-C31Ministerio de Universidades | Ref. FPU21/01176Universidade de Vig

    Adding TQ-BOT into a Third-party Learning Management System

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    Intelligent Tutoring Systems are computer programs that aim at providing personalized instruction to students. In recent years, artificial intelligence conversational robots, usually known as chatterbots, have become very popular in the Internet. In this paper we show how chatterbots can be integrated in e-Learning Systems. To perform such an integration the Service Oriented Architecture paradigm is adopted and e-learning standardization initiatives are considered. A middleware is provided to enable the integration and reuse of chatterbots by e-Learning systems enabling a tight control of their operation. Such middleware takes to account several issues such as authorising users, creating instances, transferring data to and from the chatterbot, assigning permissions to users, and subscribing to events. Our approach is applied to the specific case of TQ-Bot, which is use to track and supervise the student progress and to provide answers orienting the student to the more appropriate course contents

    Exploring the biological role of postzygotic and germinal de novo mutations in ASD

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    De novo mutations (DNMs), including germinal and postzygotic mutations (PZMs), are a strong source of causality for Autism Spectrum Disorder (ASD). However, the biological processes involved behind them remain unexplored. Our aim was to detect DNMs (germinal and PZMs) in a Spanish ASD cohort (360 trios) and to explore their role across different biological hierarchies (gene, biological pathway, cell and brain areas) using bioinformatic approaches. For the majority of the analysis, a combined ASD cohort (N = 2171 trios) was created using previously published data by the Autism Sequencing Consortium (ASC). New plausible candidate genes for ASD such as FMR1 and NFIA were found. In addition, genes harboring PZMs were significantly enriched for miR-137 targets in comparison with germinal DNMs that were enriched in GO terms related to synaptic transmission. The expression pattern of genes with PZMs was restricted to early mid-fetal cortex. In contrast, the analysis of genes with germinal DNMs revealed a spatio-temporal window from early to mid-fetal development stages, with expression in the amygdala, cerebellum, cortex and striatum. These results provide evidence of the pathogenic role of PZMs and suggest the existence of distinct mechanisms between PZMs and germinal DNMs that are influencing ASD riskAA-G was supported by Fundación María José Jove. CR-F was supported by a contract from the FEDER. Instituto de Salud Carlos III/PI1900809/Cofinanciado FEDER supported this studyS

    Four spot megrim (Lepidorhombus boscii) weight-length and weight-weight relationships in northern Iberian waters (stock 8.c, 9.a)

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    Total weight-length, gutted weight-length and total weight-gutted weight relationships were fitted for the Iberian Atlantic stock of four spot megrim (Lepidorhombus boscii) and their temporal variations were analyzed. The large sample size, size range and timeseries available allowed obtaining robust somatic parameters of combined sexes for the total weight-length relationships (a=0.0043, b=3.2008), for the gutted weight-length relationships (a=0.0055, b=3.1139), and the weight conversion factors (1.062). They are considered to best fit the current biometric relationships and most appropriate to be used in the stock assessment of the status of the stock and they contribute to a deeper knowledge of the life history traits of this species

    Megrim (Lepidorhombus whiffiagonis) weight-length relationships in the northern Bay of Biscay and Celtic Sea

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    The weight-length relationships are of a great interest in fish biology, stock assessment and fishery management, by predicting weight from length information and allowing to estimate the stock biomass. Weight-length relationships of megrim (Lepidorhombus whiffiagonis), an economically relevant flatfish species, are studied for two decades (2001 to 2019) in northern Bay of Biscay and Celtic Sea (ICES stock Div. 7.b-k, 8.abd), two important European fishing areas. More than 22000 specimens collected from commercial landings by AZTI and IEO were sampled. Total fish length, total weight and commercial gutted weight were obtained. Four five-year periods (quinquennium) (2000-04; 2005-09; 2010-14; 2015-19) were defined in the studied time-series. Both the large sample size and time-series available, as well as the collaboration between both institutions collecting complementary information from this stock, allowed obtaining robust somatic parameters and analyzing their temporal variations. A weight-length relationship model was fitted and the quinquennium and semester factors, which are of interest biologically and for assessment purposes, and their interactions were significant in the preliminary model. The weight-length relationships, both for total and gutted weight and for the combined sexes of the most recent quinquennium are presented in this work and considered the most suitable to be used in the oncoming annual assessment process of the status of this stock in northern Bay of Biscay and Celtic Sea in ICES

    Validation of Solid-State LiDAR Measurement System for Ballast Geometry Monitoring in Rail Tracks

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    The inspection and maintenance of track ballast are fundamental tasks for the preservation of the condition of railway networks. This work presents an application based on a low-cost solid-state LiDAR system, which allows the user to accurately measure the ballast geometry from a mobile inspection trolley or draisine. The solid-state LiDAR system, the LiVOX Avia, was validated on a test track through comparison with a traditional static LiDAR system, the Faro Focus 3D. The results show a standard deviation of around 6 mm for the solid-state LiDAR system. The LiVOX system also provides the capability to measure the ballast digital elevation model and profiles. The LiVOX results are in agreement with those obtained from the Faro Focus. The results demonstrate that the LiVOX system can sufficiently measure even the displacement of a single layer of ballast stones typically between 2.5 cm and 5 cm. The data provided can be easily digitalized using image processing tools and integrated into geographic information systems for infrastructure management

    La nariz lateralizada

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    In this reportwe will show our surgical method in which we try to solve this difficult surgical problem. We have done a review of those operated cases in the last thre years,done by this departement and we will show the obtained results. In the dicussion we will emphasize the great importance of the nasal septum as cartilaginous as osseous at the moment of operating on this malformation nasal.En esta comunicación presentaremos nuestra técnica quirúrgica con la que intentamos resolver este difícil problema quirurgico. Haremos una revisión de los casos operados en el servicio en los últimos 3 años y presentaremos imágenes de los resultados obtenidos. En la discusión haremos hincapié en la gran importancia del septum nasal tanto cartilaginoso como óseo a la hora de enfrentar esta dismorfia septopiramida

    Adding TQ-BOT into a Third-party Learning Management System

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    Intelligent Tutoring Systems are computer programs that aim at providing personalized instruction to students. In recent years, artificial intelligence conversational robots, usually known as chatterbots, have become very popular in the Internet. In this paper we show how chatterbots can be integrated in e-Learning Systems. To perform such an integration the Service Oriented Architecture paradigm is adopted and e-learning standardization initiatives are considered. A middleware is provided to enable the integration and reuse of chatterbots by e-Learning systems enabling a tight control of their operation. Such middleware takes to account several issues such as authorising users, creating instances, transferring data to and from the chatterbot, assigning permissions to users, and subscribing to events. Our approach is applied to the specific case of TQ-Bot, which is use to track and supervise the student progress and to provide answers orienting the student to the more appropriate course contents
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