Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2017-11-23T10:40:22Z No. of bitstreams: 0 / Made available in DSpace on 2017-11-23T10:40:22Z (GMT). No. of bitstreams: 0 / O objetivo deste trabalho foi estudar o comportamento mecânico de cilindros de compósito polimérico reforçado com fibras. Para isso, foram produzidos cilindros com extremidades abertas reforçados com fibra de basalto e fibra de vidro, utilizando a técnica de enrolamento filamentar (filament winding). Estes cilindros foram submetidos a ensaio hidrostático com carregamento circunferencial, ensaio de ruptura de anel (split disk test) e ensaio de resistência ao cisalhamento interlaminar (ILSS). Uma placa do compósito de fibra de basalto foi produzida por enrolamento filamentar, para caracterização por ensaio de resistência à tração. Todos cilindros submetidos ao ensaio hidrostático apresentaram fratura localizada em uma faixa de altura do cilindro, com extensas delaminações das camadas circunferenciais. Os compósitos epóxi/fibra de basalto superaram ou igualaram os de compósito epóxi/fibra de vidro nas comparações entre resultados dos valores das propriedades mecânicas avaliadas, nas porcentagens: resistência à tração aparente de ruptura de anel em 45% e 43% em resistência específica; ILSS, em 11%; resistência/tensão de membrana de ruptura no ensaio hidrostático, em 55%. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

Τα Πνευματικά του Ήρωνα (1ος αιώνας μ.Χ.), προϊόν μακράς παράδοσης. Στην εισαγωγή του έργου εκτίθεται το θεωρητικό υπόβαθρο που υποστηρίζει τη λειτουργία των διατάξεων που παρουσιάζονται στη συνέχεια, αλλά και υποστηρίζεται πειραματικά από ορισμένες. Η δομή του έργου ακολουθεί τη δομή του ολοκληρωμένου μαθηματικού λόγου της κλασικής αρχαιότητας, προσαρμοσμένο κατάλληλα. Θέματα που αναδεικνύουμε είναι: Η ολοκλήρωση της αρχής των συγκοινωνούντων δοχείων με την αυστηρή απόδειξη του αντίστροφου της πρότασης του Αρχιμήδη για τη σφαιρικότητα της επιφάνειας του ηρεμούντος υγρού. Η πειραματική απόδειξη της υλικότητας του αέρα. Διαδικασία που εναρμονίζει το πείραμα με προϋπάρχουσα θεωρία. Η πειραματική απόδειξη της ελαστικότητας του αέρα, ο οποίος μέχρι και τον Αριστοτέλη θεωρείται ασυμπίεστος, καθώς και της ύπαρξης κενού σε μακροσκοπική κλίμακα. Θέση που υποστηρίζεται πειραματικά από τρείς διαφορετικές διατάξεις. Η εξέλιξη της θεωρίας της αναθυμίασης (δημιουργία των ανέμων), προσθέτοντας στη φωτιά την ιδιότητα (δυνατότητα) δημιουργίας κενού. Η πειραματική (με τη διάταξη Ι.23) επαλήθευση της θέσης (που ανάγεται στον 5ο π.Χ. αιώνα) ότι τα ρευστά εναλλάσσονται στον ίδιο χώρο κατά ίσους όγκους. Μέσα από τα θέματα αυτά και την ανάδειξη των διατάξεων που τα υποστηρίζουν, επισημαίνουμε την ενσυνείδητη αποκατάσταση ενότητας θεωρίας και πράξης, ενώ φέρνουμε στο φως μια όχι ιδιαίτερα προσεγμένη κατηγορία διατάξεων αυτή των πειραματικών. / Heron’s (1st century A.D.) Pneumatics is the product of a long tradition. In the introduction to the work the theoretical background which explains the functioning of the devices which are analysed later in the work is presented. At the same time it is endorsed experimentally by some of them. The structure of the work follows that of the integrated mathematical language of classical antiquity, but appropriately adapted to the task at hand. The subjects which are highlighted are the following: The completion of the proposition of communicating vessels with the rigorous proof of the inverse of Archimedes’ proposition for the sphericity of the surface of liquids in rest; the experimental demonstration of the corporeity of air, a procedure that harmonises the experiment with a pre-existing theory; the experimental demonstration of the elasticity of air, which, until Aristotle, had been considered to be incompressible, as well as the existence of the macroscopic vacuum, a position which is supported by three different experimental devices; the evolution of exhalation theory (wind creation) adding to fire the property of being able to create a vacuum; the experimental verification (by means of device I.23) of the position (dating from the 5th century BC) that liquids alternate in the same space in equal volumes. Through these issues and the examination of the devices that support them, we draw attention to the conscious unification of theory and practice, while we also bring to light a rather neglected area, that of experimental devices.

This thesis deals with the determination of the load torque during flood conditions on the hydrostatic sectoral weir in Roudnice nad Labem. Problems are solved due to a glitch in the lowering sector. The aim of this study is to determine the resulting torque, of three selected states, which occurred at the water works. The issue was solved as a plane 2D problem using AutoCAD, in which were read the relevant data. It was also used ANSYS software, which modeled the flow of water over the weir to detect pressures acting on overflow face. All calculations are then counted in Microsoft Excel. Force balance is performed on the one-meter design.

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Made available in DSpace on 2018-06-27T19:13:06Z (GMT). No. of bitstreams: 3 Ana Marli Bulegon.pdf: 421203 bytes, checksum: de11377d3c900b2d2939aa61ef128d0d (MD5) Ana Marli Bulegon.pdf.txt: 174117 bytes, checksum: 669d56f4fa95c5b0e2013ab60bd9ebeb (MD5) Ana Marli Bulegon.pdf.jpg: 3494 bytes, checksum: 1d09d71204f70325f5d812e90a845644 (MD5) Previous issue date: 2006-12-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The purpose of this work was to investigate the contributions of the experimental activities while a classroom resource in a meaningful process of teaching-learning of Hydrostatics in High Schools. To reach this objective we have made experimental activities, with own schedules, inserted in Didactics Modules, developed according to the Three Pedagogical Moments, proposed by Delizoicov and Angotti (1991). The accomplishment of these activities occurred in the Physics laboratory of Manoel Ribas Public School in Santa Maria/RS, in a second group of students. These activities used recycle and/or material that can easily get in the students neighborhood and they where utilized to complement the conceptual approach in the expositive teaching about the topics studied. In this work we have used the learning theory of Ausubel, which offers us a theoretical reference that makes possible to improve the Physics teaching with few or no conditions or resources like in a great number of public schools. According to this theory, meaningful learning is a process that must begin trough the previous knowledge of the students, obtained through their personal experiences and buildings in the environment they are inserted and their interaction with new acquirements using teaching-learning activities that make the relationship among theses procedures easier. The acquired results of these activities showed that there was an evolution in the construction of meanings of Physics concepts involved in this subject. When they have handled recycle material the students have noticed that science is not a finished knowledge that belongs just a limited group of people but it can be studied and understood by all of us as we take part of it. The investigation has shown up that the work with classroom experimental activities has allowed the development of students attitudes and proceedings that lead them to approximate their school reality and their everyday life and also can help them to solve not only school doubts but also everyday life problems. / Este trabalho teve como objetivo investigar quais as contribuições das atividades experimentais, enquanto recurso didático, no ensino e na aprendizagem significativa de Hidrostática no nível médio. Para atingir este objetivo foram elaboradas atividades experimentais, com roteiro próprio, inseridas em Módulos Didáticos (MD), elaborados de acordo com a metodologia dos Três Momentos Pedagógicos (TMP), propostos por Delizoicov e Angotti (1991). A implementação das atividades experimentais ocorreu no laboratório didático de Física do Colégio Estadual Manoel Ribas em Santa Maria/RS, na 2ª série do ensino médio. Essas atividades fizeram uso de materiais recicláveis e/ou de fácil obtenção no meio onde os alunos vivem e foram utilizadas em complementação à abordagem conceitual, em aulas expositivas sobre os temas estudados. Neste trabalho, fez-se uso da teoria de aprendizagem de Ausubel, pois essa oferece um referencial teórico capaz de contribuir para a melhoria do ensino de Física sem implicar em condições ou recursos não existentes na grande maioria das escolas. Para este autor, a aprendizagem significativa é um processo que deve partir dos conhecimentos prévios dos alunos, adquiridos de suas construções pessoais na sua relação cotidiana com o mundo, e da interação destes com os conhecimentos novos, por meio de atividades de ensino-aprendizagem que facilitem a articulação entre esses conhecimentos. Os resultados obtidos revelaram que houve uma evolução em relação à construção de significados dos conceitos físicos envolvidos nesse assunto. Ao manusear materiais recicláveis, os alunos vislumbraram que a ciência não é um conhecimento acabado pertencente somente a um grupo limitado de pessoas, mas que pode ser estudada e entendida por todos nós, pois fazemos parte desta ciência. A investigação evidenciou que o trabalho com atividades experimentais em sala de aula possibilitou o desenvolvimento de atitudes e procedimentos nos alunos, facilitando a aproximação do mundo vivido na escola e sua vida cotidiana, permitindo-lhes resolver não apenas problemas escolares, mas também problemas cotidianos

A new primary torque control concept for hydrostatics mobile machines was introduced in 2018 [1]. The mentioned concept controls the pressure in a closed circuit by changing the angle of the hydraulic pump to achieve the desired pressure based on a feedback system. Thanks to this concept, a series of advantages are expected [2]. However, while working in a Y cycle, the primary torque controlled wheel loader has worse performance in efficiency compared to secondary controlled earthmover due to lack of recuperation ability. Alternatively, we use deep learning algorithms to improve machines’ regeneration performance. In this paper, we firstly make a potential analysis to show the benefit by utilizing the regeneration process, followed by proposing a series of CRDNNs, which combine CNN, RNN, and DNN, to precisely detect Y cycles. Compared to existing algorithms, the CRDNN with bidirectional LSTMs has the best accuracy, and the CRDNN with LSTMs has a comparable performance but much fewer training parameters. Based on our dataset including 119 truck loading cycles, our best neural network shows a 98.2 % test accuracy. Therefore, even with a simple regeneration process, our algorithm can improve the holistic efficiency of mobile machines up to 9% during Y cycle processes if primary torque concept is used.