A constant-time SLAM back-end in the continuum between global mapping and submapping: application to visual stereo SLAM

This work addresses the development and application of a novel approach, called sparser relative bundle adjustment (SRBA), which exploits the inherent flexibility of the relative bundle adjustment (RBA) framework to devise a continuum of strategies, ranging from RBA with linear graphs to classic bundle adjustment (BA) in global coordinates, where submapping with local maps emerges as a natural intermediate solution. This method leads to graphs that can be optimized in bounded time even at loop closures, regardless of the loop length. Furthermore, it is shown that the pattern in which relative coordinate variables are defined among keyframes has a significant impact on the graph optimization problem. By using the proposed scheme, optimization can be done more efficiently than in standard RBA, allowing the optimization of larger local maps for any given maximum computational cost. The main algorithms involved in the graph management, along with their complexity analyses, are presented to prove their bounded-time nature. One key advance of the present work is the demonstration that, under mild assumptions, the spanning trees for every single keyframe in the map can be incrementally built by a constant-time algorithm, even for arbitrary graph topologies. We validate our proposal within the scope of visual stereo simultaneous localization and mapping (SLAM) by developing a complete system that includes a front-end that seamlessly integrates several state-of-the-art computer vision techniques such as ORB features and bag-of-words, along with a decision scheme for keyframe insertion and a SRBA-based back-end that operates as graph optimizer. Finally, a set of experiments in both indoor and outdoor conditions is presented to test the capabilities of this approach. Open-source implementations of the SRBA back-end and the stereo front-end have been released online.Ministerio de Ciencia e Innovación (DPI 2011-25483, DPI 2014-55826-R). Fondo Europeo de Desarrollo Regional – FEDE

Evaluación del estado actual de la enseñanza de tareas de visualización y orientación espacial en Educación Primaria

En este Trabajo de Final de Grado se pretende hacer un estudio de las habilidades, conocimientos y competencias del alumnado de Educación Primaria en las tareas de orientación y visualización espacial. Actualmente la geometría es una de las grandes olvidadas dentro de las programaciones de aula a pesar de haber ocupado, a lo largo de la historia, el eje vertebrador de múltiples ciencias y diciplinas. Haciendo uso de diferentes clasificaciones y aspectos de la enseñanza y aprendizaje de la geometría, este Trabajo de Final de Grado pretende hacer un breve análisis de cuáles son los aspectos más importantes a la hora de enfrentarnos, como docentes, a la enseñanza de la geometría en general y a las tareas de visualización y orientación espacial en particular. El método a seguir en esta investigación va a ser la evaluación de conocimientos pre y post intervención en el aula y comparar su evolución en los cursos de primero y sexto de primaria, además de entre ambos cursos, dando lugar a una investigación cuantitativa, descriptiva, exploratoria y transversal.<br /

PERCEPCIÓN DE LOS ESTUDIANTES ACERCA DE LOS EXÁMENES ONLINE CON CORRECCIÓN AUTOMÁTICA EN UNA EVALUACIÓN MIXTA: RETROALIMENTACIÓN PARA LA MEJORA

Development of the information and communication technologies has led to an increase in the use of Computer Based Assessment (CBA) in higher education. In the last decade, there has been a discussion on online versus traditional pen-and-paper exams. The aim of this study was to verify whether students have reserves about auto-scored online exams, and if that is the case, to determine the reasons. The study was performed in the context of a blended assessment in which 1200 students were enrolled on a first-year physics university course. Among them, 463 answered an anonymous survey, supplemented by information obtained from an open-ended question and from interviews with students. Three factors (labelled ‘F1-Learning,’ ‘F2-Use of Tool,’ and ‘F3-Assessment’) emerged from the quantitative analysis of the survey, and an additive scale was established. We found significant differences in the ‘F3-Assessment’ factor compared to the other two factors, indicating a lower acceptance of the tool for student assessment. It seems that even though students are used to computers, they have a lack of confidence in online exams. We carried out an in-depth survey on this topic in the form of an open-ended question and by interviewing a small group of 11 students to confer strength and nuance to the quantitative results of the survey. Although their comments were positive in general, especially on ease-of-use and on its usefulness in indicating the level achieved during the learning process, there was also some criticism of the clarity of questions and the strictness of the marking system. These two factors, among others, could have been the cause of the worse perception of F3-Assessment and the origin of the students’ reluctance towards online exams and automatic scoring.El desarrollo de las tecnologías de la información y la comunicación haproducido un incremento del uso de la Computer Based Assessment (CBA,evaluación basada en ordenadores). en la educación superior. En la últimadécada, ha habido un debate sobre los exámenes online vs los escritostradicionales. El objetivo del presente estudio ha sido verificar si los estudiantes tienen prejuicios sobre los exámenes online con corrección automática, y si ese es el caso, determinar los motivos. El estudio se realizó en el contexto de una evaluación mixta que implicó a 1200 estudiantes matriculados en una asignatura de física de primer curso universitario. De entre ellos, 463 respondieron a una encuesta anónima. Del análisis cuantitativo de la encuesta surgieron tres factores (etiquetados «F1-Learning», «F2-Use of Tool» y «F3-Assessment»), y se estableció una escala aditiva. Hemos encontrado diferenciassignificativas en el factor «F3-Assessment» en comparación con los otrosdos factores, lo que indica una menor aceptación de la herramienta parala evaluación del estudiante. Parece ser que, a pesar de que los estudiantes están acostumbrados a los ordenadores, tienen una falta de confianza en los exámenes online. Para reforzar y matizar los resultados cuantitativos de la encuesta, incluimos una pregunta abierta y realizamos una entrevista a un pequeño grupo de 11 estudiantes. Aunque sus comentarios fueron en general positivos, especialmente sobre la facilidad de uso y sobre su utilidad para conocer el nivel alcanzado durante el proceso de aprendizaje, hubo algunas críticas sobre la claridad de las preguntas y el rigor del sistema de puntuación.Estos dos factores, entre otros, podrían ser la causa de la peor percepción del factor «F3-Assessment» y el origen de las reticencias de los estudiantes a los exámenes online y a la corrección automática

Effects of Atorvastatin on Vitamin D Levels in Patients With Acute Ischemic Heart Disease

Producción CientíficaVitamin D deficiency is a risk factor for osteoporosis and other chronic diseases, including type 1 diabetes, hypertension, metabolic syndrome, and ischemic heart disease. Cholesterol and vitamin D share the 7-dehydrocolesterol metabolic pathway. This study evaluated the possible effect of atorvastatin on vitamin D levels in patients with acute ischemic heart disease. Eighty-three patients (52 men and 31 women) with an acute coronary syndrome (75 with acute myocardial infarction and 8 with unstable angina) were included. After diagnosis, patients received atorvastatin as secondary prevention. Serum vitamin D was measured by high-performance liquid chromatography at baseline and at 12 months. Atorvastatin treatment produced a statistically significant decrease in cholesterol and triglyceride levels and an increase in vitamin D levels (41 19 vs 47 19 nmol/L, p 0.003). Vitamin D deficiency was decreased by 75% to 57% at 12 months. In conclusion, atorvastatin increases vitamin D levels. This increase could explain some of the beneficial effects of atorvastatin at the cardiovascular level that are unrelated to cholesterol levels

A predictive model for the maintenance of industrial machinery in the context of industry 4.0

The Industry 4.0 paradigm is being increasingly adopted in the production, distribution and commercialization chains worldwide. The integration of the cutting-edge techniques behind it entails a deep and complex revolution –changing from scheduled-based processes to smart, reactive ones– that has to be thoroughly applied at different levels. Aiming to shed some light on the path towards such evolution, this work presents an Industry 4.0 based approach for facing a key aspect within factories: the health assessment of critical assets. This work is framed in the context of the innovative project SiMoDiM, which pursues the design and integration of a predictive maintenance system for the stainless steel industry. As a case of study, it focuses on the machinery involved in the production of high-quality steel sheets, i.e. the Hot Rolling Process, and concretely on predicting the degradation of the drums within the heating coilers of Steckel mills (parts with an expensive replacement that work under severe mechanical and thermal stresses). This paper describes a predictive model based on a Bayesian Filter, a tool from the Machine Learning field, to estimate and predict the gradual degradation of such machinery, permitting the operators to make informed decisions regarding maintenance operations. For achieving that, the proposed model iteratively fuses expert knowledge with real time information coming from the hot rolling processes carried out in the factory. The predictive model has been fitted and evaluated with real data from ∼118k processes, proving its virtues for promoting the Industry 4.0 era.Ministerio de Industria, Energía y Turismo (OTRI-8.06/5.56.4826, IC4-030000-2016-3), MInisterio de Economía, Industria y Competitividad (DPI2014-55826-R). Universidad de Málaga (I-PPIT-UMA

TENDENCIAS INVESTIGATIVAS EN EL DESARROLLO DE PRODUCTOS MECATRONICOS EN LA ACTUALIDAD (RESEARCH TRENDS IN THE MECHATRONIC PRODUCTS DEVELOPMENT CURRENTLY)

Resumen La mecatrónica es un campo interdisciplinario de ciencias de la ingeniería caracterizado por la integración e interconexión entre la ingeniería mecánica, la ingeniería eléctrica y la informática. Los productos mecatrónicos son en su mayoría estructuralmente complejos, pero son una solución óptima para muchos campos de la Industria como la medicina, la agricultura, la agroindustria entre otros. Este artículo tiene como objetivo principal identificar las tendencias investigativas en los proyectos mecatrónicos NPD en la actualidad. Para ello se hace una revisión bibliográfica, citando trabajos importantes en el área a partir del año 2017 y abordando el objetivo principal de cada investigación, para así agruparlas en enfoques e identificar las tendencias investigativas actualmente. Al final se puede concluir que la tendencia es reducir el costo total en un producto mecatrónico, así como de comenzar a adaptar los conceptos de las nuevas tecnologías de la Industria 4.0 (I4.0) a los proyectos de desarrollo de nuevos productos mecatrónicos (NPD). Palabras Clave: Enfoques investigativos, NPD, proyecto mecatrónico, tendencia investigativa. Abstract Mechatronics is an interdisciplinary field of engineering sciences characterized by the integration and interconnection between mechanical engineering, electrical engineering, and computer science. Mechatronic products are mostly structurally complex, but they are an optimal solution for many fields of Industry such as medicine, agriculture, agroindustry among others. The main objective of this paper is to identify research trends in the development of mechatronics products today. To meet this objective, a bibliographic review is made, citing important works in the area from 2017 on and addressing the main objective of each investigation in order to group them into approaches and identify current investigative trends. In the end, it can be concluded that the trend is to reduce the total cost of a mechatronic product, as well as to begin to adapt the concepts of the new technologies of Industry 4.0 (I4.0) to mechatronic NPD (new project development) projects. Keywords: investigative approaches, NPD, Mechatronic Project, Research trend

Near barrier scattering of 8He on 208Pb

The exotic nucleus 8He is investigated by means of the measurement of the angular distributions of the elastic channel and the 6He and 4He fragment yields produced in the collision with a 208Pb target at two energies around the Coulomb barrier, 16 and 22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of extracting information about the structure of 8He and the relevant reaction mechanisms. In this contribution, details of the experimental setup and preliminary data on elastic cross sections are reporte

Phase III Trial of Adjuvant Capecitabine After Standard Neo-/Adjuvant Chemotherapy in Patients With Early Triple-Negative Breast Cancer (GEICAM/2003-11_CIBOMA/2004-01)

© 2019 by American Society of Clinical Oncology. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Published version of a Published Work that appeared in final form in Journal of Clinical Oncology (JCO). To access the final edited and published work see https://doi.org/10.1200/JCO.19.00904Purpose.- Operable triple-negative breast cancers (TNBCs) have a higher risk of relapse than non-TNBCs with standard therapy. The GEICAM/2003-11_CIBOMA/2004-01 trial explored extended adjuvant capecitabine after completion of standard chemotherapy in patients with early TNBC.Patients and Methods.- Eligible patients were those with operable, node-positive—or node negative with tumor 1 cm or greater—TNBC, with prior anthracycline- and/or taxane-containing chemotherapy. After central confirmation of TNBC status by immunohistochemistry, patients were randomly assigned to either capecitabine or observation. Stratification factors included institution, prior taxane-based therapy, involved axillary lymph nodes, and centrally determined phenotype (basal v nonbasal, according to cytokeratins 5/6 and/or epidermal growth factor receptor positivity by immunohistochemistry). The primary objective was to compare disease-free survival (DFS) between both arms.Results.- Eight hundred seventy-six patients were randomly assigned to capecitabine (n = 448) or observation (n = 428). Median age was 49 years, 55.9% were lymph node negative, 73.9% had a basal phenotype, and 67.5% received previous anthracyclines plus taxanes. Median length of follow-up was 7.3 years. DFS was not significantly prolonged with capecitabine versus observation [hazard ratio (HR), 0.82; 95% CI, 0.63 to 1.06; P = .136]. In a preplanned subgroup analysis, nonbasal patients seemed to derive benefit from the addition of capecitabine with a DFS HR of 0.53 versus 0.94 in those with basal phenotype (interaction test P = .0694) and an HR for overall survival of 0.42 versus 1.23 in basal phenotype (interaction test P = .0052). Tolerance of capecitabine was as expected, with 75.2% of patients completing the planned 8 cycles.Conclusion.- This study failed to show a statistically significant increase in DFS by adding extended capecitabine to standard chemotherapy in patients with early TNBC. In a preplanned subset analysis, patients with nonbasal phenotype seemed to obtain benefit with capecitabine, although this will require additional validation

Phase III Trial of Adjuvant Capecitabine After Standard Neo-/Adjuvant Chemotherapy in Patients With Early Triple-Negative Breast Cancer (GEICAM/2003-11_CIBOMA/2004-01)

Altres ajuts: Agustí Barnadas: Honoraria: Pfizer. Consulting or Advisory Role: Pfizer, Novartis, Eli Lilly. Speakers'Bureau: Roche, Pfizer, Novartis, Genomic Health International. Travel, Accommodations, Expenses: Roche, Pfizer; Miguel A. Seguí: Consulting or Advisory Role: Roche, Pfizer, Novartis, Amgen, Eisai, Eli Lilly. Speakers' Bureau: Roche, Pfizer, Amgen. Research Funding: Roche (Inst), Novartis (Inst). Travel, Accommodations, Expenses: Roche, Pfizer, Novartis, Amgen.Operable triple-negative breast cancers (TNBCs) have a higher risk of relapse than non-TNBCs with standard therapy. The GEICAM/2003-11_CIBOMA/2004-01 trial explored extended adjuvant capecitabine after completion of standard chemotherapy in patients with early TNBC. Eligible patients were those with operable, node-positive-or node negative with tumor 1 cm or greater-TNBC, with prior anthracycline- and/or taxane-containing chemotherapy. After central confirmation of TNBC status by immunohistochemistry, patients were randomly assigned to either capecitabine or observation. Stratification factors included institution, prior taxane-based therapy, involved axillary lymph nodes, and centrally determined phenotype (basal v nonbasal, according to cytokeratins 5/6 and/or epidermal growth factor receptor positivity by immunohistochemistry). The primary objective was to compare disease-free survival (DFS) between both arms. Eight hundred seventy-six patients were randomly assigned to capecitabine (n = 448) or observation (n = 428). Median age was 49 years, 55.9% were lymph node negative, 73.9% had a basal phenotype, and 67.5% received previous anthracyclines plus taxanes. Median length of follow-up was 7.3 years. DFS was not significantly prolonged with capecitabine versus observation [hazard ratio (HR), 0.82; 95% CI, 0.63 to 1.06; P =.136]. In a preplanned subgroup analysis, nonbasal patients seemed to derive benefit from the addition of capecitabine with a DFS HR of 0.53 versus 0.94 in those with basal phenotype (interaction test P =.0694) and an HR for overall survival of 0.42 versus 1.23 in basal phenotype (interaction test P =.0052). Tolerance of capecitabine was as expected, with 75.2% of patients completing the planned 8 cycles. This study failed to show a statistically significant increase in DFS by adding extended capecitabine to standard chemotherapy in patients with early TNBC. In a preplanned subset analysis, patients with nonbasal phenotype seemed to obtain benefit with capecitabine, although this will require additional validation