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Enfermedades del trabajo en la era digital: ¿están las leyes ajustadas a las nuevas realidades? Los trastornos psiquiátricos de un moderador de contenidos de Internet
Get PDF[Resumen] Un trabajador de una empresa dedicada a la moderación de contenidos de Internet fue destinado a la sección "high priority", donde los contenidos a examinar de manera completa eran relativos a terrorismo, suicidios, automutilaciones, decapitaciones de civiles asesinados por grupos terroristas y torturas. El trabajador inició una incapacidad temporal, calificada en principio como contingencia común. Reclamó para el reconocimiento de contingencia profesional, que se le reconoció en vía administrativa. La empresa recurrió en vía judicial y el Juzgado de lo Social ratificó que era contingencia profesional.[Abstract] A worker from a company dedicated to Internet content moderation was assigned to the "high priority" section, where the content to be fully examined was related to terrorism, suicides, self-mutilations, beheadings of civilians murdered by terrorist groups and tortures. The worker began a temporary disability, classified in principle as a common contingency. He claimed recognition of a professional contingency, which was recognized administratively. The company appealed to the courts and the Labor Court confirmed that it was a professional contingency
Análisis de la imagen proyectada y percibida de los destinos turísticos accesibles en la era digital
Get PDF[Resumen] La representación efectiva de la accesibilidad mejora la imagen y aumenta la cuota de demanda de los destinos, al atraer a un espectro más amplio de población. Esta tesis doctoral cubre un vacío investigativo mediante la propuesta de enfoques innovadores de análisis y recopilación de datos para estudiar la imagen de los destinos desde la perspectiva del turismo accesible.
El trabajo inicia con un análisis de la evolución conceptual del turismo accesible, combinando una revisión literaria con técnicas bibliométricas. A continuación, se analiza la imagen percibida de Aveiro (Portugal) y A Coruña (España), seleccionados como ejemplos de destinos turísticos accesibles, aplicando técnicas de raspado de reseñas en línea y minería de datos. Finalmente, se desarrolla, prueba y valida mediante técnicas estadísticas un instrumento de medición para valorar y comparar la imagen proyectada de los destinos turísticos accesibles, utilizando una muestra de 42 webs oficiales de turismo de España y Portugal.
Entre otros resultados, se constata que el turismo accesible es una rama de estudio que ha evolucionado desde la adaptación de entornos para personas con discapacidad, a un modelo turístico que beneficia a toda la población. De hecho, se observa que existe una relación significativa entre las valoraciones que los visitantes otorgan a los recursos turísticos y las condiciones de accesibilidad de los mismos. Las webs de turismo españolas obtuvieron resultados significativamente superiores en la proyección de los atributos de accesibilidad de los destinos en comparación con las portuguesas.
Se concluye que las reseñas en línea constituyen una valiosa fuente de información para mejorar la experiencia de los visitantes, y que los destinos deberían optimizar la proyección de aspectos psicológicos clave para atraer a personas con necesidades especiales de acceso, tales como transmitir el compromiso del sector turístico con la accesibilidad.[Resumo] A representación efectiva da accesibilidade mellora a imaxe e aumenta a cota de demanda dos destinos, ao atraer a un espectro máis amplo de poboación. Esta tese doutoral cobre un baleiro investigativo mediante a proposta de enfoques innovadores para a análise e recompilación de datos para o estudo da imaxe dos destinos desde a perspectiva do turismo accesible.
O traballo inicia cunha análise da evolución conceptual do turismo accesible, combinando unha revisión literaria con técnicas bibliométricas. A continuación, analízase a imaxe percibida de Aveiro (Portugal) e A Coruña (España), seleccionados como exemplos de destinos turísticos accesibles, aplicando técnicas de raspado de recensións en liña e minería de datos. Finalmente, desenvólvese, proba e analiza mediante técnicas estatísticas un instrumento de medición para valorar e comparar a imaxe proxectada dos destinos turísticos accesibles, utilizando unha mostra de 42 webs oficiais de turismo de España e Portugal.
Entre outros resultados, constátase que o turismo accesible é unha rama de estudo que evolucionou desde a adaptación de contornas para persoas con discapacidade, a un modelo turístico que beneficia a toda a poboación. De feito, obsérvase que existe unha relación significativa entre as valoracións que os visitantes outorgan aos recursos turísticos e as condicións de accesibilidade dos mesmos. As webs de turismo españolas obtiveron resultados significativamente superiores na proxección dos atributos de accesibilidade dos destinos en comparación coas portuguesas.
Conclúese que as recensións en liña constitúen unha valiosa fonte de información para mellorar a experiencia dos visitantes, e que os destinos deberían optimizar a proxección de aspectos psicolóxicos clave para atraer a persoas con necesidades especiais de acceso, tales como transmitir o compromiso do sector turístico coa accesibilidade.[Abstract] Effective representation of accessibility enhances the image and increases the demand share for destinations by attracting a broader spectrum of the population. This doctoral thesis addresses a research gap by proposing innovative approaches for data analysis and collection to study the image of destinations from the perspective of accessible tourism.
The work begins with an analysis of the conceptual evolution of accessible tourism, combining a literature review with bibliometric techniques. It then examines the perceived image of Aveiro (Portugal) and A Coruña (Spain), selected as examples of accessible tourist destinations, applying online review scraping techniques and data mining. Finally, a measurement instrument is developed, tested, and analyzed using statistical techniques to assess and compare the projected image of accessible tourist destinations, using a sample of 42 official tourism websites from Spain and Portugal.
Among other findings, it was noted that accessible tourism has evolved from adapting environments for people with disabilities to a tourism model that benefits the entire population. Indeed, a significant relationship was observed between visitors’ ratings of tourist resources and their accessibility conditions. Spanish tourism websites scored significantly higher in projecting the accessibility attributes of destinations compared to their Portuguese counterparts.
It is concluded that online reviews are a valuable source of information for enhancing visitors’ experiences, and destinations should optimize the projection of key psychological aspects to attract people with special access needs, such as conveying the tourism sector’s commitment to accessibility.Esta investigación ha recibido la financiación del Programa de ayudas para estancias predoctorales de investigación INDITEX-UDC 2022-202
Validation of the Scientific Program for the Dark Energy Spectroscopic Instrument
Get PDFData Availability
The Data Release 9 of the DESI Legacy Imaging Surveys is available at https://legacysurvey.org/dr9/.
Documentation of DESI data access is maintained at https://data.desi.lbl.gov/doc/access/.
All data points used in published graphs are available in Zenodo: doi: [doi:10.5281/zenodo.10063934].[Abstract]: The Dark Energy Spectroscopic Instrument (DESI) was designed to conduct a survey covering 14,000 deg2 over 5 yr to constrain the cosmic expansion history through precise measurements of baryon acoustic oscillations (BAO). The scientific program for DESI was evaluated during a 5 month survey validation (SV) campaign before beginning full operations. This program produced deep spectra of tens of thousands of objects from each of the stellar Milky Way Survey (MWS), Bright Galaxy Survey (BGS), luminous red galaxy (LRG), emission line galaxy (ELG), and quasar target classes. These SV spectra were used to optimize redshift distributions, characterize exposure times, determine calibration procedures, and assess observational overheads for the 5 yr program. In this paper, we present the final target selection algorithms, redshift distributions, and projected cosmology constraints resulting from those studies. We also present a One-Percent Survey conducted at the conclusion of SV covering 140 deg2 using the final target selection algorithms with exposures of a depth typical of the main survey. The SV indicates that DESI will be able to complete the full 14,000 deg2 program with spectroscopically confirmed targets from the MWS, BGS, LRG, ELG, and quasar programs with total sample sizes of 7.2, 13.8, 7.46, 15.7, and 2.87 million, respectively. These samples will allow exploration of the Milky Way halo, clustering on all scales, and BAO measurements with a statistical precision of 0.28% over the redshift interval z < 1.1, 0.39% over the redshift interval 1.1 < z < 1.9, and 0.46% over the redshift interval 1.9 < z < 3.5.This material is based upon work supported by the U.S. Department of Energy (DOE), Office of Science, Office of High-Energy Physics, under contract No. DE-AC02-05CH11231, and by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility under the same contract. Additional support for DESI was provided by the U.S. National Science Foundation (NSF), Division of Astronomical Sciences under contract No. AST-0950945 to the NSF's National Optical-Infrared Astronomy Research Laboratory; the Science and Technology Facilities Council of the United Kingdom; the Gordon and Betty Moore Foundation; the Heising-Simons Foundation; the French Alternative Energies and Atomic Energy Commission (CEA); the National Council of Science and Technology of Mexico (CONACYT); the Ministry of Science and Innovation of Spain (MICINN), and by the DESI Member Institutions: https://desi.lbl.gov/collaborating-institutions. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the U.S. National Science Foundation, the U.S. Department of Energy, or any of the listed funding agencies.
The authors are honored to be permitted to conduct scientific research on Iolkam Du'ag (Kitt Peak), a mountain with particular significance to the Tohono O'odham Nation.United States. Department of Energy; DE-AC02-05CH11231United States. National Science Foundation; AST-095094
Finding a needle in a haystack: insights on feature selection for classification tasks
Get PDFFinanciado para publicación en acceso aberto: CRUE-CSIC/Springer Nature[Abstract]: The growth of Big Data has resulted in an overwhelming increase in the volume of data available, including the number of features. Feature selection, the process of selecting relevant features and discarding irrelevant ones, has been successfully used to reduce the dimensionality of datasets. However, with numerous feature selection approaches in the literature, determining the best strategy for a specific problem is not straightforward. In this study, we compare the performance of various feature selection approaches to a random selection to identify the most effective strategy for a given type of problem. We use a large number of datasets to cover a broad range of real-world challenges. We evaluate the performance of seven popular feature selection approaches and five classifiers. Our findings show that feature selection is a valuable tool in machine learning and that correlation-based feature selection is the most effective strategy regardless of the scenario. Additionally, we found that using improper thresholds with ranker approaches produces results as poor as randomly selecting a subset of features.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research has been financially supported in part by the Spanish Ministerio de Ciencia e Innovación MCIN/AEI/10.13039/501100011033 and “NextGenerationEU”/PRTR under Grants [PID2019-109238GB-C22; TED2021-130599A-I00], and by the Xunta de Galicia (ED431C 2022/44) with the European Union ERDF funds. CITIC, as a Research Center of the University System of Galicia, is funded by Consellería de Educación, Universidade e Formación Profesional of the Xunta de Galicia, Spain through the European Regional Development Fund (ERDF) and the Secretaría Xeral de Universidades (Ref. ED431G 2019/01).Xunta de Galicia; ED431C 2022/44Xunta de Galicia; ED431G 2019/0
Evaluation of femtosecond laser texturing on carbonate heritage stones
Get PDF[Abstract]: The effect of femtosecond laser texturing on Carrara marble, Montesclaros marble, and Redueña dolostone was evaluated. Mineralogical characterisation, laser structuring of thin sections and hand samples of the three heritage stones were carried out. The topography of the textured surfaces was obtained by means of interferometric microscopy, and a petrographic study of laser-generated craters in thin sections was performed to elucidate the effect of the crystalline structure of calcite on the morphology of the laser-generated structures. The differences observed in thin sections allowed to understand the differences observed in laser-structured bulk samples of the three heritage stones; which is key aspect when designing conservative strategies based on laser texturing.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in
the framework of the Strategic Funding, with UIDB/00073/2020 and CEECIND/03568/2017
projects. Authors acknowledge Erasmus+ program: HERDADE Consortium (2021-1-ES01-
KA130-HED-360 000007519). This paper has been written during a scientific stay at the
Centro de Ciencias Sociales y Humanas (CSIC) in Madrid within the framework of the project
entitled: Use and function of the peninsular granary caves: an approximation based on
archaeobotany (PID2021-127936NB-I00).Portugal. Fundação para a Ciência e a Tecnologia; UIDB/00073/2020Portugal. Fundação para a Ciência e a Tecnologia; CEECIND/03568/201
Machine learning-based WENO5 scheme
Get PDF[Abstract]: Machine learning (ML) is becoming a powerful tool in Computational Fluid Dynamics (CFD) to enhance the accuracy, efficiency, and automation of simulations. Currently, in the design of shock-capturing methods, there is still a heavy reliance on the expertise and scientific knowledge of each author, particularly in nonlinear components such as smoothness indicators and weighting functions. ML has the potential to reduce this dependency, since by leveraging large datasets, they can learn intricate patterns and make accurate predictions of these functions. In this work we present a neural network that compute the weighting functions in the WENO5 scheme. The proposed WENO5-NN scheme generalizes well for different resolutions, and in most of the cases tested, it outperforms the classical WENO5-JS scheme.X. Nogueira and L. Ramírez acknowledge the support provided by the [Grant PID2021-125447OB-I00] funded by MCIN/AEI/ 10.13039/501100011033 and by “ERDF A way of making Europe”, and the funds by [Grant TED2021-129805B-I00] funded by MCIN/AEI/ 10.13039/501100011033 and by the “European Union NextGenerationEU/PRTR”. They also acknowledge the funding provided by the Xunta de Galicia (grant #ED431C 2022/06).Xunta de Galicia; ED431C 2022/0
Fillers and methods to improve the effective (out-plane) thermal conductivity of polymeric thermal interface materials – A review
Get PDF[Abstract]: The internet of things and growing demand for smaller and more advanced devices has created
the problem of high heat production in electronic equipment, which greatly reduces the work
performance and life of the electronic instruments. Thermal interface material (TIM) is placed in
between heat generating micro-chip and the heat dissipater to conduct all the produced heat to
the heat sink. The development of suitable TIM with excellent thermal conductivity (TC) in both
in-plane and through-plane directions is a very important need at present. For efficient thermal
management, polymer composites are potential candidates. But in general, their thermal conductivity
is low compared to that of metals. The filler integration into the polymer matrix is one of
the two approaches used to increase the thermal conductivity of polymer composites and is also
easy to scale up for industrial production. Another way to achieve this is to change the structure
of polymer chains, which fall out of the scope of this work. In this review, considering the first
approach, the authors have summarized recent developments in many types of fillers with
different scenarios by providing multiple cases with successful strategies to improve throughplane
thermal conductivity (TPTC) (k⊥). For a better understanding of TC, a comprehensive
background is presented. Several methods to improve the effective (out-plane) thermal conductivity
of polymer composites and different theoretical models for the calculation of TC are also
discussed. In the end, it is given a detailed conclusion that provides drawbacks of some fillers,
multiple significant routes recommended by other researchers to build thermally conductive
polymer composites, future aspects along with direction so that the researchers can get a
guideline to design an effective polymer-based thermal interface material.This research was funded by Ministry of Science and Technology of the People’s Republic of China, “Light Shipbuilding Fire-
Resistant Sandwich Panels with Improved Balance of Acoustic Insulation, Mechanical and Environmentally-Friendly Properties”,
grant number 2019YFE0124000.China. Ministry of Science and Technolog
Generating Commonsense Explanations with Answer Set Programming
Get PDF[Abstract] In this thesis, we explore the notion of commonsense explanation in the context of Artificial Intelligence by extending the formalism of Answer Set Programming (ASP) with formal annotations. To this aim, we define the concept of support graphs to account for the multiple explanations for each model of a logic program, andwe provide different operations to filter irrelevant information from the graphs. These definitions are implemented in a tool called xclingo that additionally allows the specification of natural language, commonsense explanations. xclingo obtains the support graphs via an ASP meta-encoding that is proved to be correct. We study different examples in the context of ASP such as planning, problem-solving, or diagnosis, among others, and we analyze the effect of alternative annotations
for the same scenario, illustrating the need for explanation design. Additionally, we address
the generation of non-technical explanations of Machine Learning models for real users in a pair of problems from other disciplines (Medicine and Pharmacy), covering both symbolic and sub-symbolic learning algorithms.[Resumen] En esta tesis, exploramos la noción de “commonsense explanation” en el contexto de la Inteligencia Artificial mediante la extensión del formalismo Answer Set Programming (ASP) con anotaciones formales.
Con este objetivo, definimos el concepto de “support graphs” para obtener múltiples explicaciones de cada modelo de un programa lógico, y proporcionamos diferentes operaciones para filtrar la información irrelevante de estos grafos. Dichas definiciones son implementadas por una herramienta llamada xclingo que adicionalmente permite la especificación de explicaciones “commonsense” en lenguaje natural. xclingo obtiene los “support graphs” empleando un meta-programa ASP, cuya corrección es demostrada. Estudiamos los diferentes ejemplos en el contexto de ASP tales como planificación, resolución de problemas o diagnóstico, entre otros, y analizamos el efecto de diferentes anotaciones para el mismo escenario, ilustrando la necesidad de diseñar las explicaciones. Adicionalmente,
abordamos la generación de explicaciones no técnicas de modelos de Aprendizaje Automático
con usuarios reales en dos problemas de otras disciplinas (Medicina y Farmacia), cubriendo tanto algoritmos de aprendizaje simbólico como subsimbólico.[Resumo] Nesta tese, exploramos a noción de “commonsense explanation” no contexto da Intelixencia Artificial mediante a extensión do formalismo Answer Set Programming (ASP) con anotacións formais. Con este obxectivo, definimos o concepto de “support graphs” para obter múltiples explicacións de cada modelo dun programa lóxico, e proporcionamos diferentes operacións para filtrar a información irrelevante de destes grafos. Ditas definicións son implementadas por unha ferramenta chamada xclingo que adicionalmente permite a especificación de explicacións “commonsense” en linguaxe natural. xclingo
obtén Os “support graphs” empregando un meta-programa ASP, cuxa corrección é demostrada. Estudamos os diferentes exemplos no contexto de ASP tales como planificación, resolución de problemas ou diagnóstico, entre outros, e analizamos o efecto de diferentes anotacións para o mesmo escenario, ilustrando a necesidade de deseñar as explicacións. Adicionalmente, abordamos a xeración de explicación non técnicas de modelos de Aprendizaxe Automático con usuarios reais en dous problemas de outras disciplinas (Medicina e Farmacia), cubrindo tanto algoritmos de aprendizaxe simbólico como subsimbólico
Evidence evaluation in craniofacial superimposition using likelihood ratios
Get PDFFinanciado para publicación en acceso aberto: Universidad de Granada / CBUA[Abstract]: Craniofacial Superimposition is a forensic identification technique that supports decision-making when skeletal remains are involved. It is based on the analysis of the overlapping of a post-mortem skull with ante-mortem facial photographs. Despite its importance and wide applicability, the process remains complex and challenging. To address this, computerized methods have been proposed, but subjectivity and qualitative reporting persist in decision-making. This study introduces an evidence evaluation system proposal based on Likelihood Ratios, previously used in other forensic fields, such as DNA, voice, fingerprint, and facial comparison. We present a novel application of this framework to Craniofacial Superimposition. Our work comprises three experiments in which our LR system is trained and tested under distinct conditions concerning facial images: the first utilizes frontal facial photographs; the second employs lateral facial photographs; and the last one integrates both frontal and lateral facial photographs. In the three experiments, the proposed LR system stands out in terms of calibration and discriminating power, providing practitioners with a quantitative tool for evidence evaluation and integration. However, the lack of massive actual data obliged us to focus our study on synthetic data only. Therefore, it should be considered a proof of concept. Nevertheless, the resulting likelihood-ratio system offers objective decision support in Craniofacial Superimposition. Further studies are required to validate in a real scenario the conclusions achieved.This research has been developed within the R&D project CONFIA (grant PID2021-122916NB-I00), funded by MICIU/AEI/10.13039/501100011033 and by ERDF/EU, and by grant FORAGE (B-TIC-456-UGR20) funded by Consejería de Universidad, Investigación e Innovación, both funded by “ERDF A way of making Europe”. Miss Martínez-Moreno is supported by grant PRE2022-102029 funded by MICIU/AEI/10.13039/501100011033 and the FSE+. Dr. Valsecchi's work is supported by Red.es under grant Skeleton-ID2.0 (2021/C005/00141299). Dr. Ibáñez's work is funded by the Spanish Ministry of Science, Innovation and Universities under grant RYC2020-029454-I and by Xunta de Galicia, Spain by grant ED431F 2022/21. The authors thank Pierre Guyomarc’h for providing us with the data used in this research. Funding for open access charge: Universidad de Granada / CBUA.Xunta de Galicia; ED431F 2022/21Junta de Andalucía; B-TIC-456-UGR2
Análise de Rendemento en Plataformas Data Lakehouse: Snowflake e Databricks
Get PDF[Resumo]: Este traballo compara o rendemento de dúas das plataformas Data Lakehouse máis populares na actualidade: Snowflake e Databricks, mediante a execución de benchmarks de referencia no seu ámbito, como é o caso de TPC-DS. A análise dos resultados permitiu coñecer en profundidade as distintas configuracións e optimizacións que permiten ambas plataformas. As principais recomendacións e conclusións subliñan a importancia de non sobredimensionar os recursos de cómputo, senón adaptalos ao tamaño dos datos cos que traballar para lograr unha eficiencia óptima. Ademais, tamén se descubriu que o uso de AWS como provedor de cloud para Snowflake pode mellorar o seu rendemento respecto a Azure e GCP. Por último, para aqueles escenarios que implican a carga frecuente de grandes volumes de datos, Databricks demostrou ser máis eficaz.[Abstract]: This work compares the performance of two of the most popular Data Lakehouse platforms at the moment: Snowflake and Databricks, by running reference benchmarks in their field, such as TPC-DS. The analysis of the results provided in-depth knowledge of the different configurations and optimizations available on both platforms. Key recommendations and conclusions include the importance of not oversizing computational resources but rather tailoring them to match the data workload for optimal efficiency. Additionally, it was found that using AWS as the cloud provider for Snowflake can enhance performance. Lastly, for scenarios involving frequent loading of large datasets, Databricks proved to be more effective.Traballo fin de mestrado (UDC.FIC). Enxeñaría Informática. Curso 2023/202