Machine learning-based fault detection and diagnosis in electric motors

Fault diagnosis is critical to any maintenance industry, as early fault detection can prevent catastrophic failures as well as a waste of time and money. In view of these objectives, vibration analysis in the frequency domain is a mature technique. Although well established, traditional methods involve a high cost of time and people to identify failures, causing machine learning methods to grow in recent years. The Machine learning (ML) methods can be divided into two large learning groups: supervised and unsupervised, with the main difference between them being whether the dataset is labeled or not. This study presents a total of four different methods for fault detection and diagnosis. The frequency analysis of the vibration signal was the first approach employed. This analysis was chosen to validate the future results of the ML methods. The Gaussian Mixture model (GMM) was employed for the unsupervised technique. A GMM is a probabilistic model in which all data points are assumed to be generated by a finite number of Gaussian distributions with unknown parameters. For supervised learning, the Convolution neural network (CNN) was used. CNNs are feedforward networks that were inspired by biological pattern recognition processes. All methods were tested through a series of experiments with real electric motors. Results showed that all methods can detect and classify the motors in several induced operation conditions: healthy, unbalanced, mechanical looseness, misalignment, bent shaft, broken bar, and bearing fault condition. Although all approaches are able to identify the fault, each technique has benefits and limitations that make them better for certain types of applications, therefore, a comparison is also made between the methods.O diagnóstico de falhas é fundamental para qualquer indústria de manutenção, a detecção precoce de falhas pode evitar falhas catastróficas, bem como perda de tempo e dinheiro. Tendo em vista esses objetivos, a análise de vibração através do domínio da frequência é uma técnica madura. Embora bem estabelecidos, os métodos tradicionais envolvem um alto custo de tempo e pessoas para identificar falhas, fazendo com que os métodos de aprendizado de máquina cresçam nos últimos anos. Os métodos de Machine learning (ML) podem ser divididos em dois grandes grupos de aprendizagem: supervisionado e não supervisionado, sendo a principal diferença entre eles é o conjunto de dados que está rotulado ou não. Este estudo apresenta um total de quatro métodos diferentes para detecção e diagnóstico de falhas. A análise da frequência do sinal de vibração foi a primeira abordagem empregada. foi escolhida para validar os resultados futuros dos métodos de ML. O Gaussian Mixture Model (GMM) foi empregado para a técnica não supervisionada. O GMM é um modelo probabilístico em que todos os pontos de dados são considerados gerados por um número finito de distribuições gaussianas com parâmetros desconhecidos. Para a aprendizagem supervisionada, foi utilizada a Convolutional Neural Network (CNN). CNNs são redes feedforward que foram inspiradas por processos de reconhecimento de padrões biológicos. Todos os métodos foram testados por meio de uma série de experimentos com motores elétricos reais. Os resultados mostraram que todos os métodos podem detectar e classificar os motores em várias condições de operação induzida: íntegra, desequilibrado, folga mecânica, desalinhamento, eixo empenado, barra quebrada e condição de falha do rolamento. Embora todas as abordagens sejam capazes de identificar a falha, cada técnica tem benefícios e limitações que as tornam melhores para certos tipos de aplicações, por isso, também e feita uma comparação entre os métodos

Magistrates’ Travelling Libraries : The Circulation of Normative Knowledge in the Portuguese Empire of the Late 18th Century

The pluricontinental Portuguese judicial administration was characterized by intensive movement of personnel around and between its dominions, forming a global network of rotating judicial posts. Along with these individuals, their books circulated, too. The present study focuses on the lists of books of eleven magistrates appointed to judicial posts in a range of locations throughout Portuguese America between 1799 and 1807. Censorship sources allow us to identify the books chosen by these itinerant magistrates as being indispensable for the exercise of their judicial function. In view of the cost of shipping, the books’ weight and, above all, the temporary character of the functionaries’ posts, judges established travelling libraries, portable collections of essential professional books. Identifying the books selected by judges as the work tools for their overseas judicial activities provides a good idea of the legal literature available in the final years of the Portuguese Ancien Régime. Finally, this investigation sheds light on how – and what kind of – normative information circulated in Portugal’s colonies along with these agents of the Crown.Peer reviewe

Evaluation of the radiopacity and physical-chemistry properties of the root canal filling materials

Orientadores: Lourenço Correr Sobrinho, Manoel D. Sousa NetoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: No presente estudo, dois experimentos, com base na Especificação n° 57 para materiais obturadores de canais radiculares da American National Standardl American Dental Association (ANSI/ADA), foram realizados. No primeiro experimento, foi avaliada a radiopacidade dos cimentos AR PlusTM, Endofill@, EndoREZTM e EpiphanyTM, e de cones de guta-percha Dentsply-Maillefer@ e ResilonTM, por meio da digitalização direta de imagens (sistema de imagem digital Digora). Placas de acrílico, contendo 6 orificios (5 mm de diâmetro x 1 mm de espessura), foram preenchidas com os materiais, posicionadas juntamente com um penetrômetro de alumínio, padronizada pela Especificação n° 57 da ANSI/ADA, e radiografadas a uma distância foco-objeto de 30 em, com tempo de exposição de 0,2 s. As médias- das densidades radiográficas de cada material foram obtidas em escala de cinza. Os valores decrescentes de densidade radiográfica dos materiais estudados foram: ResilonTM (214,28), AR PlusTM (206,42), gutta-percha (199,04), EpiphanyTM (188,04), Endofill@ (180,34) e EndoREZTM (178,18). No segundo experimento, foi avaliado se a redução do volume de material obturador de canal radicular necessário para a confecção de corpos-de-prova para os testes de solubilidade e alteração dimensional pós-presa possibilitaria a execução dos testes e-atenderia as exigências da Especificação n° 57 da ANSI/ADA. Inicialmente, determinou-se a densidade dos corpos-de-prova padronizados (ANSI/ADA), para o teste de solubilidade e para o teste de alteração dimensional pós-presa, utilizando-se o cimento EndofiU@. Após a determinação da densidade, moldes, de menores dimensões, foram confeccionados e divididos em 6 grupos para cada um dos testes. Os moldes originais, padronizados pela Especificação n° 57 da ANSI/ADA, foram utilizados como grupo controle. Para a confecção dos corpos-de-prova, foram utilizados os cimentos AR PlusTM e Endofill@. Para solubilidade, os corpos-de-prova foram divididos em grupos, sendo estes imersos em volumes de água destilada e deionizada diferenciados, de acordo com a massa do corpo-de-prova: GSl (20 x 1,5 mm, imerso em 50 ml de água destilada, estabelecido pela ANSI/ADA); GS2 (14,14 x 1,5 mm, 25 ml); GS3 (10 x 1,5 mm, 12,5 ml); GS4 (8,94 x 1,5 nurí, 10 ml); GS5 (7,75 x 1,5 mm, 7,5 ml); GS6 (6,32 xl,5 mm, 5 rnl); GS7 (4,47 x 1,5 mm, 2,5 rnl). Dois corpos-de-prova, de cada grupo, foram pesados, em conjunto, antes. de serem imersos em água destilada e deionizada, e armazenados a 37°C, por 24 h. Após esse período, foram secos e pesados novamente. A solubilidade foi calculada pela perda de massa do conjunto (em %) e a água destilada utilizada foi submetida à espectrofotometria de absorção atômica, para análise da presença dos íons Zn e Ca. Para alteração dimensional pós-presa, os seguintes grupos foram formados: GADl (12 x 6 mm, imerso em 30 ml de água destilada, estabelecido pela ANSI/ADA); GAD2 (6,09 x 6 mm, 15,22 rnl); GAD3 (4,48 x 6 mm, 11,19 ml); GAD4 (3,58 x 6 mm, 8,96 ml); GAD5 (6,04 x 4 mm, 6,72 rnl); GAD6 (4,03 x 4mm, 4,48 ml); GAD7 (3,58 x 3 mm, 2,24 ml). Após a mensuração do comprimento, com micrômetro, as amostras foram imersas em água destilada a 37°C, por 30 dias, removidas, secas e mensuradas novamente. Com os comprimentos iniciais e finais, determinou-se a variação percentual para cada grupo. Para o teste de solubilidade, houve correlação entre a massa inicial e a diferença entre massas inicial e final para os diferentes grupos. O cimento . Endofill@ apresentou valor médio de solubilidade estatisticamente superior ao AR PlusTM é (1,55% e 0,06%, respectivamente). Para alteração dimensional pós-presa, houve correlação entre o comprimento inicial e a diferença entre comprimentos inicial e final para os diferentes grupos. O cimento Endofill@ apresentou contração (0,56%) e o AR PlusTM, expansão (0,62%). Concluiu-se que os cimentos AR PlusTM, Endofill@, EndoREZTM e EpiphanyTM, e de cones de guta-percha Dentsply-Maillefer@ e ResilonTM, apresent~ram radiopacidade superior aos 3 mm de alumínio, determinados pela Especificação n° 57 da ANSI/ADA e que a redução do volume de material obturador de canal radicular necessário para a confecção de corpos-de-prova para os testes de solubilidade e alteração dimensional pós-presa, possibilitou a execução dos testes, atendendo as exigências da Especificação n° 57 da ANSI/ADAAbstract: In the present study, two experiments, according to American National Standardl American Dental Association (ANSI/ ADA) Specification No. 57 for endodontic sealing materiaIs, were performed. In the first experiment, the radiopacity of AR PlusTM, Endofilf~, EndoREZTM, and EpiphanyTM sealers, and gutta-percha (Dentsply-Maillefer) and ResilonTM cones were evaluated using direct digital image processing (digital image DigoraTM system). Acrylic plates, containing 6 wells (1 mm in depth and 5 mm in diameter), were filled with the materiaIs, positioned together with an aluminum stepwedge, according to ANSI/ADA Specification 57, and radiographed on an object-to-focus distance of 30 cm, with exposure time of 0.2 s. The averages of radiographic densities for each material were obtained using gray scale values. The decreasing values of radiographic density of the studied materiaIs were: ResilonTM (214.28), AR PlusTM (206.42), guttapercha (199.04), EpiphanyTM (188.04), Endofill@ (180.34), and EndoREZTM (178.18). In the second experiment, it was evaluated the possibility of decreasing the volume of material necessary for the production of test samples for solubility and dimensional change following setting tests, which comply with ANSI/ADA Specification No. 57, without committing the accuracy of the results of these methods. Initially, it was obtained the density of the standard test samples (ANSI/ADA), for solubility, and dimensional ch~nge following setting tests, using Endofill@ sealer. Once original density was determined, moulds, with smaller dimensions, were prepared and divided into 6 groups, ITom each <me of the test. The moulds standardized to ANSI/ ADA Specification 57 were used as control group. To preparing of test samples, it was used AR PlusTM and Endofill@ sealers. For solubility test, the test samples were divided into groups, being the samples immersed into volumes of distilIed and deionized water, according to the mass ofthe test sample: GS1 (20 mm x 1.5 mm, immersed into 50 rnL distilled water, according to ANSI/ADA); GS2 (14.14 mm x 1.5 mm, 25 rnL); GS3 (10 mm x 1.5 mm, 12.5 rnL); GS4 (8.94 mm x 1.5 mm, 10 mL); GS5 (7.75 mm x 1.5 mm, 7.5 rnL); GS6 (6.32 mm x 1.5 mm, 5 rnL); GS7 (4.47 mm x 1.5 mm, 2.5 rnL). Two test samples of eaclí group, were weighted, in set, before being immersed in distilled and deionized water, and stored at 37°C, for 24 h. After this time, they were dried and weighted again. The solubility was calculated using the weight loss (%) and the distilled water was evaluated through atomic absorption spectrometry analysis, to verify the presence ofZn, and Ca ions. For dimensional change following setting test, the following groups were performed: GDC1 (12 x 6 mm, immersed into 30 rnL distilled water, according to ANSI/ADA); GDC2 (6.09 x 6 mm, 15.22 rnL); GDC3 (4.48 x 6 mm, 11.19 rnL); GDC4 (3.58 x 6 mm, 8.96 rnL); GDC5 (6.04 x 4 mm, 6.72 rnL); GDC6 (4.03 x 4mm, 4.48 rnL); GDC7 (3.58 x 3 mm, 2.24 rnL). After height measurement using amicrometer, the test samples were immersed into distilled water, and stored at 37°C, for 30 days, removed, dried and measured again. With initial and final heights, it was established the percentage variation for each group. For solubility test, there was correlation between the initial mass and the difference among initial and final masses for the different groups. The Endofilfi) sealer present~d mean value significant1y higher than AR PlusTM sealer (1.55% and 0.06%, respectively). For dimensional change following setting, there was . correlation between the initial height and the difference among initial and final heights for the different groups. The Endofill@ sealer presented 'shrinkage (0.56%) and AR PlusTM sealer, expansion (0.62%). It can be conc1uded that AR PlusTM, Endofill@, EndoREZTM, and EpiphanyTM sealers, and gutta-percha (Dentsply-Maillefer) and ResilonTM cones showed radiopacity above the 3 mm of aluminum reco.mmended by ANSI/ADA Specification 57. In addition, the volume reduction of root canal filling material necessary for the production of test samples for solubility and dimensional change following setting tests made possible the execution ofthe tests, following the recommendations of ANSI/ADA Specification 57DoutoradoMateriais DentariosDoutor em Materiais Dentário

The space-time torsion in the context of the Exact Foldy-Wouthuysen Transformation for a Dirac fermion

In this work we focus our attention in the inconsistency that appears when the Semi-Exact Foldy-Wouthuysen transformation for the Dirac field interacting with space-time torsion field is performed. In order to solve this problem, we present a new involution operator that makes possible to perform the exact transformation when torsion field is present. Such operator has a structure, well known in the literature, composed of the product of an operator that acts in the matrices space and another one that acts in the function space. We also present the bound state of this theory and discuss the possible experimental analysis

Methodology of power analysis in Michel Foucault’s thought

This work seeks to reconstruct Michel Foucault\u27s power analysis methodology in order to understand how he overcomes the classical theories of power by proposing a way of seeing power as a relation that occurs between subjects. In order to do so, the relations between truth and power will be analyzed, as well as the methodological premises elaborated by the author in his main works on power. &nbsp

Manidipine in the treatment of stage I and II essential hypertensive patients with overweight or android obesity. A brazilian multicentre study of efficacy, tolerability and metabolic effects

OBJECTIVE: To evaluate the efficacy, metabolic effects and tolerability of manidipine used in the treatment of stage I and II essential hypertensive patients with overweight or android obesity. METHODS: By an open-label, non comparative protocol in 11 Brazilian clinical research centers 102 hypertensive patients of both sexes with over weight or central obesity were treated with manidipine 10 to 20mg once daily for 12 weeks. Blood pressure, heart rate and adverse events were monitored. Fasting plasma glucose, total, HDL and LDL-cholesterol and triglicerides were determined at both placebo period and end of active treatment. Also in 12 patients, insulin sensitivity index was evaluated during placebo and manidipine treatment. RESULTS: Blood pressure was reduced from 159±15 / 102±5mmHg to 141±15 / 90±8mmHg with the treatment without any noticeable change in heart rate. Manidipine-efficacy rate was 71.9% with 51.1% of blood pressure normalization. No significant changes in metabolic parameters were noticed. Tolerability to manidipine was very high and at the last visit 87.1% of the treated patients were free of any adverse event. CONCLUSION: Manidipine is an adequate, highly effective, exempt of metabolic effects and safe option for treatment of stage I and II essential hypertensive patients with overweight or android obesity.OBJETIVO: Avaliar a eficácia anti-hipertensiva, efeitos metabólicos e tolerabilidade da manidipina no tratamento de hipertensos essenciais estágio I e II com sobrepeso ou obesidade do tipo andróide. MÉTODOS: Em estudo aberto, não comparativo, realizado em 11 centros brasileiros de pesquisa, 102 pacientes de ambos os sexos com sobrepeso ou obesidade central, foram tratados por 12 semanas com manidipina em dose única diária de 10 a 20mg e avaliadas pressão arterial, freqüência cardíaca e a presença de eventos adversos. Ao final dos períodos placebo e de droga ativa foram obtidos os valores plasmáticos da glicemia de jejum, colesterol total e frações e triglicérides. Em 12 pacientes foi avaliada a sensibilidade à insulina. RESULTADOS: A manidipina reduziu a pressão arterial de 159±15 / 102±5mmHg para 141±15 / 90±8mmHg sem acarretar aumento da freqüência cardíaca. A taxa de eficácia foi de 71,9% com 51,1% de normalização pressórica. Não foram observadas alterações significativas dos parâmetros metabólicos. A tolerabilidade da manidipina foi muito boa e no final do estudo 87,1% estavam livres de qualquer reação adversa. CONCLUSÃO: A manidipina constitui opção adequada, altamente eficaz, livre de efeitos metabólicos e segura para tratamento de hipertensos estágios I e II com sobrepeso ou obesidade andróide.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Hospital do Rim e HipertensãoUNIFESP, EPM, Hospital do Rim e HipertensãoSciEL

Richness and community structure of sand dunes (restinga) in Santa Catarina: subsidies for ecological restoration

The coast of Balneario Piçarras city (Santa Catarina) is being onstantly degraded by human action. This study aimed to haracterize the richness and vegetation structure of two areas of herbaceous restinga (preserved and degraded) of the coastal plain of this city. The lora was mapped by using the patrolling method. Identification was done by comparative morphology and specialized bibliography. The phytosociology was based on the plot method with allocation oriented parallel to the coast line. There were 48 pecies, 44 genera and 22 families identified. Fabaceae, Asteraceae and Poaceae are the richest families. The H’ index was 3.9 in the preserved area and 2.1 in the degraded area. The community tructure was represented by eight and 16 species in the degraded and preserved areas, respectively. In degraded areas, species as Spartina ciliata, Ipomoea pes-caprae, Sphagneticola trilobata and Paspalum vaginatum have the greater importance of coverage, structuring the community. In the preserved area, the organization structure of the community is given by anavalia rosea, Remirea maritima, Stenotaphrum secundatum, Spartina ciliata and Acicarpha spathulata species. These species are considered pioneers and with a great potential of fixing dunes, which reflects their importance to the achievement of a future restoration work of thedamaged area of the restinga in question. Keywords: Coastal plain; floristic; phytosociology; recovery of degraded areas

Elastocaloric Effect in Graphene Kirigami

Kirigami, a traditional Japanese art of paper-cutting, has recently been explored for its elastocaloric effect (ECE) in kirigami-based materials (KMs), where applying strain induces temperature changes. In this study, we investigate the ECE in a nanoscale graphene kirigami (GK) monolayer, representing the thinnest possible KM, to better understand this phenomenon. Through molecular dynamics simulations, we analyze the temperature change and coefficient of performance (COP) of the nanoscale GK architecture. Our findings reveal that while GKs lack the intricate temperature changes observed in macroscopic KMs, they exhibit a substantial temperature change of approximately 9.32 K (23 times higher than that of macroscopic KMs, which is about 0.4K) for heating and -3.50 K for cooling. Additionally, they demonstrate reasonable COP values of approximately 1.57 and 0.62, respectively. It is noteworthy that the one-atom-thick graphene configuration prevents the occurrence of the complex temperature distribution observed in macroscopic KMs.Comment: 14 pages, 06 figures, and 01 tabl