Analysis of reliable deployment of TDOA local positioning architectures

.Local Positioning Systems (LPS) are supposing an attractive research topic over the last few years. LPS are ad-hoc deployments of wireless sensor networks for particularly adapt to the environment characteristics in harsh environments. Among LPS, those based on temporal measurements stand out for their trade-off among accuracy, robustness and costs. But, regardless the LPS architecture considered, an optimization of the sensor distribution is required for achieving competitive results. Recent studies have shown that under optimized node distributions, time-based LPS cumulate the bigger error bounds due to synchronization errors. Consequently, asynchronous architectures such as Asynchronous Time Difference of Arrival (A-TDOA) have been recently proposed. However, the A-TDOA architecture supposes the concentration of the time measurement in a single clock of a coordinator sensor making this architecture less versatile. In this paper, we present an optimization methodology for overcoming the drawbacks of the A-TDOA architecture in nominal and failure conditions with regards to the synchronous TDOA. Results show that this optimization strategy allows the reduction of the uncertainties in the target location by 79% and 89.5% and the enhancement of the convergence properties by 86% and 33% of the A-TDOA architecture with regards to the TDOA synchronous architecture in two different application scenarios. In addition, maximum convergence points are more easily found in the A-TDOA in both configurations concluding the benefits of this architecture in LPS high-demanded applicationS

Table Organization Optimization in Schools for Preserving the Social Distance during the COVID-19 Pandemic

[EN] The COVID-19 pandemic has supposed a challenge for education. The school closures during the initial coronavirus outbreak for reducing the infections have promoted negative effects on children, such as the interruption of their normal social relationships or their necessary physical activity. Thus, most of the countries worldwide have considered as a priority the reopening of schools but imposing some rules for keeping safe places for the school lessons such as social distancing, wearing facemasks, hydroalcoholic gels or reducing the capacity in the indoor rooms. In Spain, the government has fixed a minimum distance of 1.5 m among the students’ desks for preserving the social distancing and schools have followed orthogonal and triangular mesh patterns for achieving valid table dispositions that meet the requirements. However, these patterns may not attain the best results for maximizing the distances among the tables. Therefore, in this paper, we introduce for the first time in the authors’ best knowledge a Genetic Algorithm (GA) for optimizing the disposition of the tables at schools during the coronavirus pandemic. We apply this GA in two real-application scenarios in which we find table dispositions that increase the distances among the tables by 19.33% and 10%, respectively, with regards to regular government patterns in these classrooms, thus fulfilling the main objectives of the paper.SIMinisterio de Ciencia, Innovación y Universidade

Effect of Gamma radiation on mycotoxins solutions

Due to the high toxicity of mycotoxins, many methods have been used to reduce or eliminate them from food and feed. Gamma radiation is one technique that has been investigated with some promising results in degradation of some mycotoxins from food. The aim of this study was to clarify the effect of gamma irradiation on aflatoxin B1 (AFB1) aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2), ochatoxin A (OTA) and zearelone (ZEA). The effect of the presence of moisture during the irradiation process was evaluated. Solutions with the same initial mycotoxin concentration were submitted to gamma radiation doses ranging from 0 to 10.0 kGy, at distinct moisture level – dehydrated, in water, and in methanol:water solution. Mycotoxins levels were determined by high-performance liquid chromatography with fluorescence detection (HPLC-FL), and photochemical post-column derivatization (for aflatoxins). The results showed degradation of mycotoxins with doses above 3.0 kGy, but only when irradiated in aqueous environment. With dehydrated samples, no significant reduction was observed. The results showed that gamma radiation was effective in reducing the mycotoxins concentration, but the presence of water (mainly due to the formation of hydroxyl radicals) had a very significant effect.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/79364/201, SFRH/BPD/43922/2008Programa Operacional do Norte (Adl. Portugal) - ChestNutsRad (contract number 13198

Social media and eating disorder psychopathology: a systematic review

The relationship between socialization through social media (SM) and eating disorders (EDs) is a serious problem for public health, largely affecting the mental health of younger people. This work aimed to identify scientific works addressing ED psychopathologies, studying their relationship with SM usage. In this systematic review, we analyze the available scientific evidence, thereby providing tools for intervention, prevention, and treatment. A systematic review and PRISMA analysis of narrative syntheses was carried out. Works were selected from the databases of Web of Science, Scopus, PubMed, and PsycINFO. Out of a total of 257 references, 19 articles were identified and selected; among them, correlational studies predominated. A growing interest in the subject matter was identified, as it is undergoing constant changes. The investigations found that EDs and SM usage are influenced by the time spent on SM, the type of interactions, and shared photographs, as well as gender and sociocultural context

Hyperconnectivity Proposal for Smart Manufacturing

[EN] Smart Manufacturing is characterized by the digitization and massive communication of Cyber-Physical Systems under the Industrial Internet of Things paradigm. However, the heterogeneity of communication protocols hinders connectivity among assets due to lack of interoperability. Moreover, the decomposition of the classical production hierarchy towards decentralized self-organization makes the implementation of interoperability in industrial environments key to help decision-making. In this sense, the interoperability of heterogeneous assets (e.g., external, internal, and human) has been defined as hyperconnectivity and supposes a technological challenge in the scientific literature. To prove this novel hyperconnectivity definition, the authors propose and develop a novel hyperconnected demonstrator where all types of assets are interconnected in a case study consisting of the automation of an inspection process. For this purpose, an industrial internet platform has been used for connecting industrial equipment creating a collaborative environment through the use of interoperability. In this regard, it has been possible to communicate assets among the cloud, humans, and CPS with a processing time of less than 10 ms, which demonstrates that the technological challenge of implementing the hyperconnectivity concept of this paper has been successfully addressed.SIThis research has been developed and funded by the Spanish Ministry of Science and Innovation project grant number PID2019-108277GB-C21/AEI/10.13039/501100011033 and by the Universidad de León.Ministerio de Ciencia, Innovación y Universidade

Digital Twin for Automatic Transportation in Industry 4.0

[EN] Industry 4.0 is the fourth industrial revolution consisting of the digitalization of processes facilitating an incremental value chain. Smart Manufacturing (SM) is one of the branches of the Industry 4.0 regarding logistics, visual inspection of pieces, optimal organization of processes, machine sensorization, real-time data adquisition and treatment and virtualization of industrial activities. Among these tecniques, Digital Twin (DT) is attracting the research interest of the scientific community in the last few years due to the cost reduction through the simulation of the dynamic behaviour of the industrial plant predicting potential problems in the SM paradigm. In this paper, we propose a new DT design concept based on external service for the transportation of the Automatic Guided Vehicles (AGVs) which are being recently introduced for the Material Requirement Planning satisfaction in the collaborative industrial plant. We have performed real experimentation in two different scenarios through the definition of an Industrial Ethernet platform for the real validation of the DT results obtained. Results show the correlation between the virtual and real experiments carried out in the two scenarios defined in this paper with an accuracy of 97.95% and 98.82% in the total time of the missions analysed in the DT. Therefore, these results validate the model created for the AGV navigation, thus fulfilling the objectives of this paper.SIMinisterio de Ciencia, Innovación y Universidade

Oral lipomas in a Brazilian population : a 10-year study and analysis of 450 cases reported in the literature

Objectives: Lipomas are common benign mesenchymal neoplasms that rarely occur in the oral cavity and correspond to less than 4.4% of all benign oral soft tissue tumors. This study describes the clinical, radiological and histological features of cases of oral lipomas seen over a period of 10 years and compared the findings with those reported in the literature. Study Design: All cases of oral lipomas seen between 1999 and 2009 were retrieved from the archives of the Stomatology Division of the Federal University of Ceará, Brazil. Age, gender, tumor location, clinical findings, duration, histological subtypes, and treatment outcome were recorded. In addition, the English-language literature was searched for studies published between 1966 and 2009. Results: Ten patients (6 women and 4 men) were enrolled in this study. The mean age was 53.4 years (range: 21-73 years). The specific sites involved were the oral mucosa (n=5), vestibule (n=3), gingiva (n=1), and retromolar region (n=1). The mean size of the tumors was 1.94 cm (range 1.0 to 3.0 cm). Radiographically, only one case appeared as a radiolucent area on occlusal film. Microscopically, 4 cases were classified as simple lipoma, 4 as fibrolipoma, 1 as myxoid lipoma, and 1 as angiolipoma. The duration of the tumors ranged from 2 to 84 months, with a mean duration of 30.4 months. All cases were treated by simple surgical excision and there was no recurrence after a mean post-treatment period of 34.5 months. The findings were compared with 450 cases of oral lipomas reported in the literature. Conclusions: Lipomas continue to be an uncommon neoplasm of the oral cavity. Radiography is a valuable tool due to the possible occurrence of bone involvement. Surgical excision is the treatment of choice and recurrence is not expected

Docência no ensino superior: : trabalho e formação no período da pandemia

The article deals with the work and training of History teachers at the Federal University of Maranhão (UFMA) in the face of the tensions and contradictions presented by the reality of higher education during the pandemic. The research methodology is based on a critical qualitative approach, with dialectical historical materialism as the basis for analysis. The theoretical framework is based on the categories of work and teacher training. The analysis as a whole reveals that work and training is a type of work that is affected by time to the detriment of bureaucracy, which reverberates in individuality and competitiveness that was intensified even more during the pandemic.El artículo aborda el trabajo y la formación de los profesores de Historia de la Universidad Federal de Maranhão (UFMA) frente a las tensiones y contradicciones presentadas por la realidad de la enseñanza superior durante la pandemia. La metodología de investigación se basa en un abordaje cualitativo crítico, analizado a partir del materialismo histórico dialéctico. El marco teórico se basa en las categorías de trabajo y formación docente. El conjunto de los análisis revela que el trabajo y la formación son un tipo de trabajo que se ve afectado por el tiempo en detrimento de la burocracia, lo que repercute en la individualidad y la competitividad que se intensificó aún más durante la pandemia.O artigo trata sobre o trabalho e a formação de professores/as do curso de História da Universidade Federal do Maranhão (UFMA) diante das tensões e contradições apresentadas pela realidade do ensino superior no período da pandemia. A metodologia da pesquisa funda-se na abordagem qualitativa crítica, tendo como base de análise o materialismo histórico dialético. O referencial teórico está assentado nas categorias trabalho e formação docente. O conjunto das análises revela que o trabalho e a formação são um tipo de trabalho que é afetado pelo tempo em detrimento da burocracia, o que reverbera em individualidade e competitividade que foi intensificada ainda mais no período da pandemia

Docência no ensino superior: entre a experiência e o experimento

This article is the result of a completed thesis research whose general objective was to understand the limits and possibilities of the dialogue between the experiential knowledge, the formation and the work of the professors of the History course of the Federal University of Maranhão in the face of the tensions and contradictions presented by the reality of higher education. The research methodology is based on a critical qualitative approach, based on dialectical historical materialism. Thematic Oral History was used. The theoretical framework is based on the categories of experiential knowledge, work and teacher training. The research revealed through the category experiential dimension that teachers use their references and experiences, in an attempt to establish dialogues with teaching situations carried out individually or collectively, since there are no established spaces for the reflection of practical knowledge in light of theoretical knowledgeEste artigo é resultado de pesquisa de tese concluída que teve por objetivo geral compreender os limites e as possibilidades do diálogo entre os saberes experienciais, a formação e o trabalho dos/as professores/as do curso de História da Universidade Federal do Maranhão diante das tensões e contradições apresentadas pela realidade do ensino superior. A metodologia da pesquisa funda-se na abordagem qualitativa crítica, a partir do materialismo histórico dialético. Para tanto utilizou-se a História Oral temática. O referencial teórico está assentado nas categorias saberes experienciais, trabalho e formação docente. A pesquisa desvelou por meio da categoria dimensão experiencial que, os docentes acionam suas referências e experiências, na tentativa de estabelecer diálogos com as situações de ensino realizadas individual ou coletivamente, uma vez que não existe espaços instituídos para a reflexão dos saberes da prática à luz dos conhecimentos teóricos

Analysis of synchronous localization systems for UAVs urban applications

[EN] Unmanned-Aerial-Vehicles (UAVs) represent an active research topic over multiple fields for performing inspection, delivery and surveillance applications among other operations. However, achieving the utmost efficiency requires drones to perform these tasks without the need of human intervention, which demands a robust and accurate localization system for achieving a safe and efficient autonomous navigation. Nevertheless, currently used satellite-based localization systems like GPS are insufficient for high-precision applications, especially in harsh scenarios like indoor and deep urban environments. In these contexts, Local Positioning Systems (LPS) have been widely proposed for satisfying the localization requirements of these vehicles. However, the performance of LPS is highly dependent on the actual localization architecture and the spatial disposition of the deployed sensor distribution. Therefore, before the deployment of an extensive localization network, an analysis regarding localization architecture and sensor distribution should be taken into consideration for the task at hand. Nonetheless, no actual study is proposed either for comparing localization architectures or for attaining a solution for the Node Location Problem (NLP), a problem of NP-Hard complexity. Therefore, in this paper, we propose a comparison among synchronous LPS for determining the most suited system for localizing UAVs over urban scenarios. We employ the Cràmer–Rao-Bound (CRB) for evaluating the performance of each localization system, based on the provided error characterization of each synchronous architecture. Furthermore, in order to attain the optimal sensor distribution for each architecture, a Black-Widow-Optimization (BWO) algorithm is devised for the NLP and the application at hand. The results obtained denote the effectiveness of the devised technique and recommend the implementation of Time Difference Of Arrival (TDOA) over Time of Arrival (TOA) systems, attaining up to 47% less localization uncertainty due to the unnecessary synchronization of the target clock with the architecture sensors in the TDOA architecture.S