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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Otimização de traços de concreto : estudo aplicado a postes de concreto armado visando o aumento da vida útil / Optimization of concrete mixtures: study applied to reinforced concrete poles aiming to increase service life

Reginato, Lucas Alexandre January 2014 (has links)
A energia elétrica é, sem dúvida, um recurso indispensável para a sociedade moderna. A mesma revolucionou o modo de vida do ser humano em todos os aspectos e melhorou substancialmente sua qualidade de vida. A distribuição da energia elétrica cabe ao Sistema Elétrico de Potência – SEP, dividido basicamente em três macro setores: geração, transmissão e distribuição. A eletricidade é efetivamente entregue aos consumidores pelo sistema de distribuição, formado principalmente por redes aéreas sustentadas por postes, estes na sua maioria, feitos de concreto armado. Tendo em vista o adequado fornecimento da energia elétrica à sociedade, se faz necessário assegurar as linhas de distribuição de energia, na qual os postes exercem papel fundamental. Entende-se que o aumento da vida útil dos postes de concreto armado pode colaborar para a redução da manutenção da rede de distribuição, reduzindo o investimento em substituições ou reparos em postes por parte das concessionárias Deste modo, esse trabalho propõe a otimização do traço utilizado na produção de postes de concreto armado em uma empresa de artefatos de concreto, visando à vida útil do mesmo. Para tanto foram realizados estudos visando o aprimoramento da composição dos agregados, adição de material pozolânico, adição de fibras e utilização de aditivos superplastificantes. Para análise dos traços em escala real foram moldados 12 postes, tipo duplo T com 9 metros de comprimento, empregando 5 traços com características distintas. Os postes foram avaliados seguindo a metodologia e requisitos da NBR 8451-1 (ABNT, 2011), parâmetros de resistência mecânica do concreto e penetração de íons cloreto ASTM C1202 (2012). Por meio da análise dos resultados, é apresentado o traço indicado para produção de postes de concreto armado, onde foi possível aprimorar o traço atualmente produzido pela empresa, reduzindo o consumo de cimento de 429 kg/m³ para 351 kg/m³ e reduzindo a taxa de penetração de íons cloreto e aumentando a vida útil do poste de concreto armado de 10 para 60 anos. À vista disso, foi possível aumentar a vida útil do elemento, mesmo com a redução do consumo de cimento e o custo para a produção do traço de concreto. / Electricity is undoubtedly an indispensable resource for modern society. The same has revolutionized the way of life of the human being in all aspects and substantially improved their quality of life. The distribution of electricity is up to the Electric Power System - EPS, basically divided into three macro sectors: generation, transmission and distribution. Electricity is actually delivered to consumers by the distribution system, consisting mainly of overhead lines supported by pylons, these mostly made of reinforced concrete. Given the adequate supply of electricity to society, it is necessary to ensure the power distribution lines, in which the poles play a fundamental role. It is understood that increasing the useful life of reinforced concrete poles can contribute to the reduction of maintenance of the distribution network, reducing investment in replacements or repairs on poles by concessionaires. Thus, this paper proposes the optimal trait used in the production of reinforced concrete poles on a firm concrete artifacts, seeking the life of it For both studies were performed in order to improve the composition of households, adding pozzolanic material, adding fiber and use of superplasticizers additives. For analysis of traces in real scale 12 posts, T type double with 9 feet long, employing five traits were shaped with distinct characteristics. The posts were evaluated following the methodology and requirements of NBR 8451-1 (ABNT, 2011), the mechanical response of concrete and chloride ion penetration ASTM C1202 (2012). By analyzing the results, the dash indicated for production of reinforced concrete poles, where it was possible to improve the trace currently produced by the company, reducing the cement content of 429 kg / m³ to 351 kg / m³ and reducing the rate appears penetration of chloride ions and increasing the service life of reinforced concrete post 10 to 60 years. In view of this, it was possible to extend the life of the element, even with the reduction in cement consumption and the cost for the production of concrete mix.
82

Do controle de impacto à promoção do fluxo: um debate sobre polos geradores de tráfego em São Paulo / From impact control to the promotion of flow: a debate about poles that generate traffic in São Paulo

Lemos, Leticia Lindenberg 26 January 2017 (has links)
No Brasil e em São Paulo as políticas públicas de mobilidade urbana foram historicamente orientadas para promover a fluidez dos automóveis. A partir do século XXI, particularmente na segunda década, o debate sobre mobilidade se desloca, passando a focar nas pessoas, ao invés de veículos, e na promoção de modos ativos. Esta pesquisa se insere neste contexto, analisando o instrumento de controle de impacto no sistema de circulação urbana denominado Polos Geradores de Tráfego. A partir de novos conceitos referenciais para mobilidade urbana, discutimos a evolução do marco regulatório referencial para este instrumento. Analisamos, então, como ele tem sido aplicado pela Companhia de Engenharia de Tráfego através de uma ampla amostra desses empreendimentos e do estudo de caso comparativo entre dois shopping centers em São Paulo. Os resultados indicam que o instrumento tratado aqui e sua aplicação apresentam baixa aderência às condições territoriais, levando a uma abordagem limitada dos elementos de produção e atração de viagens. Com esta pesquisa, esperamos contribuir para o debate atual sobre a produção de cidades mais sustentáveis e mais acessíveis espacial e socialmente. / In Brazil and in São Paulo, the public policies concerning urban mobility have been historically oriented to promote the traffic flow for automobile. On the beginning of the XXI century, and particularly on its second decade, the debate about mobility started to a focus on people, rather than vehicles, and on the promotion of active modes. In this context, this research analysis the instrument used to control the impact on the circulation system, entitled Traffic Generating Poles. Based on new references for mobility policies we discuss the evolution of the regulatory framework for this instrument. We analyze how it has been implemented by the Traffic Engineering Company through a large sample of these buildings and a case study comparing two shopping centers in São Paulo. The results indicate that the instrument and its implementation present a low adherence to the conditions of the territory, leading to a limited approach on the elements of production and attraction of trips. With this research, we hope to contribute to the current debate on the production of cities that are more accessible both spatially and socially, and more environmentally friendly.
83

Do controle de impacto à promoção do fluxo: um debate sobre polos geradores de tráfego em São Paulo / From impact control to the promotion of flow: a debate about poles that generate traffic in São Paulo

Leticia Lindenberg Lemos 26 January 2017 (has links)
No Brasil e em São Paulo as políticas públicas de mobilidade urbana foram historicamente orientadas para promover a fluidez dos automóveis. A partir do século XXI, particularmente na segunda década, o debate sobre mobilidade se desloca, passando a focar nas pessoas, ao invés de veículos, e na promoção de modos ativos. Esta pesquisa se insere neste contexto, analisando o instrumento de controle de impacto no sistema de circulação urbana denominado Polos Geradores de Tráfego. A partir de novos conceitos referenciais para mobilidade urbana, discutimos a evolução do marco regulatório referencial para este instrumento. Analisamos, então, como ele tem sido aplicado pela Companhia de Engenharia de Tráfego através de uma ampla amostra desses empreendimentos e do estudo de caso comparativo entre dois shopping centers em São Paulo. Os resultados indicam que o instrumento tratado aqui e sua aplicação apresentam baixa aderência às condições territoriais, levando a uma abordagem limitada dos elementos de produção e atração de viagens. Com esta pesquisa, esperamos contribuir para o debate atual sobre a produção de cidades mais sustentáveis e mais acessíveis espacial e socialmente. / In Brazil and in São Paulo, the public policies concerning urban mobility have been historically oriented to promote the traffic flow for automobile. On the beginning of the XXI century, and particularly on its second decade, the debate about mobility started to a focus on people, rather than vehicles, and on the promotion of active modes. In this context, this research analysis the instrument used to control the impact on the circulation system, entitled Traffic Generating Poles. Based on new references for mobility policies we discuss the evolution of the regulatory framework for this instrument. We analyze how it has been implemented by the Traffic Engineering Company through a large sample of these buildings and a case study comparing two shopping centers in São Paulo. The results indicate that the instrument and its implementation present a low adherence to the conditions of the territory, leading to a limited approach on the elements of production and attraction of trips. With this research, we hope to contribute to the current debate on the production of cities that are more accessible both spatially and socially, and more environmentally friendly.
84

Finite Element Analyses Of Differential Shrinkage-induced Cracking In Centrifugally Cast Concrete Poles

Tanfener, Tugrul 01 September 2012 (has links) (PDF)
Poles are used as an important constituent of transmission, distribution and communication structures / highway and street lighting systems and other various structural applications. Concrete is the main production material of the pole industry. Concrete is preferred to steel and wood due not only to environmental and economic reasons but also because of its high durability to environmental effects and relatively less frequent maintenance requirements. Centrifugal casting is the most preferred way of manufacturing concrete poles. However, misapplication of the method may lead to a significant reduction in strength and durability of the poles. Segregation of concrete mixture is a frequent problem of centrifugal casting. The segregated concrete within the pole cross-section possesses different physical properties. In particular, the shrinkage tendency of the inner concrete, where the cement paste is accumulated, becomes significantly larger. Differential shrinkage of hardened concrete across the pole section gives rise to the development of internal tensile stresses, which, in turn, results in longitudinal cracking along the poles. There is a vast literature on experimental studies of parameters affecting differential shrinkage of centrifugally cast poles. This research aims to computationally investigate the differential shrinkage-induced internal stress development and cracking of concrete poles. To this end, two and three-dimensional mathematical models of the poles are constructed and finite element analyses of these models are carried out for different scenarios. The computationally obtained results that favorably agree with the existing experimental data open the possibility to improve the centrifugal manufacturing technique by using computational tools.
85

Accumulated labours : First Nations art in British Columbia, 1922-1961

Hawker, Ronald W. 11 1900 (has links)
In this dissertation, I chart the conflicting and shifting assertions of meaning for Northwest Coast objects in Canada through a series of representational projects implemented between 1922 and 1961, beginning in January 1922, with the prosecution by the Department of Indian Affairs of participants in the Cranmer potlatch. The intersection between the concept of the 'fatal impact' or death of First Nations societies under European modernization, federal assimilationist policies, the government's exercise of disciplinary control, and the expansion of public museum collections was explicitly illustrated when the Lekwiltok, Mamalillikulla, and the Nimpkish peoples surrendered over seventeen cases of ceremonial objects in exchange for suspended sentences for violating the potlatch ban. The dissertation concludes by examining the Gitanyow agreement, engineered between 1958 and 1961, in which Gitanyow laws, histories and territories would be published by the government of British Columbia in exchange for the removal and replication of four crest poles. The raising of the poles' replicas in 1961 coincided with Canadian parliament's approval of the enfranchisement of First Nations people, the theoretical end to the era of assimilation in Canada. These events bookend a period in which representation continued to be entwined with politica and social conditions created by the Indian Act that depended on promulgating views that First Nations lifeways were vanishing. However, production of Northwest Coast objects retained significance throughout this period, such objects playing complex and multifaceted roles. Because of the symbolic and financial value many Euro-Canadians attached to First Nations objects, "art" proved an avenue for communicating First Nations-related social, political and economic issues. The objects produced or displayed between 1922 and 1961 operated through the projects I describe in the intertwined transformative processes of identity construction and boundary marking among individual First Nations groups and within Canadian national identity. Through these projects, important steps were taken in formulating two major characteristics of the post-1960 period: 1. a burgeoning market in Northwest Coast objects constructed as "traditional;" and 2. First Nations activism for land claims and self-determination using "tradition" and "art" as a platform in activism for land claims and self-determination.
86

Δημιουργία μοντέλου πεπερασμένων στοιχείων σύγχρονης μηχανής και μελέτη σφαλμάτων δρομέα

Ιωάννου, Κωνσταντίνος 06 September 2010 (has links)
Η παρούσα διπλωματική εργασία εκπονήθηκε στο τμήμα Ηλεκτρολόγων Μηχανικών και Τεχνολογίας υπολογιστών του πανεπιστημίου Πατρών και το θέμα της αφορά τη μελέτη σφαλμάτων στο δρομέα τριφασικής σύγχρονης μηχανής έκτυπων πόλων με τη δημιουργία δισδιάστατου μοντέλου πεπερασμένων στοιχείων. Σκοπός της διπλωματικής εργασίας είναι η ανάλυση της λειτουργίας τριφασικού σύγχρονου κινητήρα έκτυπων πόλων κατά την ασύγχρονη εκκίνηση του σε τρείς περιπτώσεις, με σφάλμα σε μία μπάρα ενός έκτυπου πόλου, στο δακτύλιο βραχυκύκλωσης και χωρίς κανένα σφάλμα και σύγκριση των αποτελεσμάτων. Για την σχεδίαση του μοντέλου του τριφασικού κινητήρα χρησιμοποιήθηκαν τα κατασκευαστικά στοιχεία μιας πραγματικής τριφασικής μηχανής πού προορίζεται για λειτουργία σε υδροηλεκτρικό σταθμό παραγωγής ενέργειας με τη δυνατότητα λειτουργίας σαν αντλία. Για την κατασκευή και εξομοίωση του μοντέλου στις δύο διαστάσεις χρησιμοποιήθηκε το λογισμικό Opera-2d, το οποίο χρησιμοποιεί την μέθοδο των πεπερασμένων στοιχείων, μια αριθμητική μέθοδο για να προσομοιώσει τη φυσική λειτουργία των ηλεκτρικών μηχανών. Για την επιτυχία του μοντέλου χρειάστηκαν αρκετές μετρήσεις και υπολογισμοί από τα δεδομένα που είχαμε τα οποία δεν παραθέτονται. Με την περάτωση του μοντέλου εξομοιώθηκαν διαφορετικές λειτουργίες στη μόνιμη κατάσταση για εξακρίβωση της ακρίβειας του μοντέλου που κατασκευάσαμε. Η διπλωματική εργασία χωρίζεται σε πέντε κεφάλαια, όπου αρχικά στο πρώτο κεφάλαιο γίνεται μια γενική περιγραφή των βασικών εννοιών της ηλεκτρικής ενέργειας και των βασικών αρχών που διέπουν την κατασκευή και λειτουργία των σύγχρονων μηχανών και γενικότερα των τριφασικών σύγχρονων μηχανών έκτυπων πόλων. Στο κεφάλαιο 2 εξηγείται πιο αναλυτικά η λειτουργία του τριφασικού σύγχρονου κινητήρα και οι μέθοδοι της εκκίνησης του με έμφαση στην ασύγχρονη εκκίνηση. Επίσης παρουσιάζονται μερικά δεδομένα γενικά γύρω από τους υδροηλεκτρικούς σταθμούς και τον τρόπο λειτουργίας τους. Στη συνέχεια στο κεφάλαιο 3 δίνονται επιγραμματικά τα κυρίως βήματα που ακολουθήσαμε κατά την σχεδίαση του μοντέλου πεπερασμένων στοιχείων μαζί με τα σχέδια των τμημάτων του κινητήρα και τα κυριότερα παράθυρα ελέγχου του λογισμικού Opera-2d. Στο κεφάλαιο 4 δίνονται τα βήματα και τα παράθυρα ελέγχου για τις παραμέτρους της ανάλυσης και παρουσιάζονται τα αποτελέσματα των εξομοιώσεων που για τις τρείς περιπτώσεις τους υγιούς μοντέλου, του μοντέλου με σπασμένη μπάρα και το μοντέλο με σφάλμα στο δακτύλιο βραχυκύκλωσης. Στο τέλος του κεφαλαίου 4 εξάγονται τα συμπεράσματα μας για την ασύγχρονη εκκίνηση του σύγχρονου κινητήρα και πως αυτή επηρεάζεται από τα σφάλματα σε μία μπάρα βραχυκύκλωσης και στο δακτύλιο βραχυκύκλωσης. / This thesis was produced in the department of Electrical Engineering and Computer Science at the University of Patras and involves the study of rotor errors in a three phase synchronous motor with salient poles with the help of finite element analysis. The purpose of this thesis is the monitoring of a three-phase synchronous motor with salient poles during asynchronous starting, with one broken bar, broken ring and in a healthy state for comparing the results. For the design of the motor we used the machine data of a real motor which is used in a pumped storage hydroelectric generator. For the creation of the model in two dimensions we used the software Opera-2d, which uses the finite element method to simulate the operation of electric machines. For the success of the design, a number of measurements and calculations was taken from the machine data which are not included in the thesis. Also, after the completion of the model, we run simulations in steady state to verify that the model was running according to designer parameters. The thesis is divided in five chapters. In the first chapter there is a general description of the basic knowledge of electric energy and the principles regarding the construction and operation of synchronous machines and in particular three-phase synchronous machines with salient poles. In chapter 2 there is a more detailed description of the operating characteristics of a three-phased synchronous motor and the starting methods, with emphasis at asynchronous starting. Additionally, there is some information regarding hydro-generator stations. Chapter 3 shows the main steps followed during the design stage of the model and it includes images of the main parts of the motor and the control windows of the software Opera-2d. Chapter 4 starts by showing the main steps and control windows for the analysis parameters and this is followed by the results of the simulations for the three cases: healthy motor, with broken bar and with broken ring. Finally the conclusions for the asynchronous starting of a synchronous motor and how it is affected by a broken bar and a broken ring at the rotor, are presented at the end of chapter 4.
87

Μελέτη σύγχρονης μηχανής εκτύπων πόλων και υπολογισμός παραμέτρων της με τη μέθοδο πεπερασμένων στοιχείων

Αλεξανδροπούλου, Παρασκευή 19 July 2012 (has links)
Η παρούσα διπλωματική εργασία εκπονήθηκε στο τμήμα Ηλεκτρολόγων Μηχανικών και Τεχνολογίας Υπολογιστών του Πανεπιστημίου Πατρών και το θέμα αφορά την μελέτη της σύγχρονης μηχανής με έκτυπους πόλους και τον υπολογισμό παραμέτρων της με την μέθοδο των πεπερασμένων στοιχείων. Σκοπός της διπλωματικής εργασίας είναι ο υπολογισμός των επαγωγιμοτήτων της σύγχρονης μηχανής με έκτυπους πόλους. Πιο συγκεκριμένα θα υπολογίσουμε τις αυτεπαγωγιμότητες και τις αμοιβαίες επαγωγιμότητες του στάτη και του δρομέα. Για την σχεδίαση του μοντέλου της τριφασικής σύγχρονης μηχανής χρησιμοποιήθηκαν τα κατασκευαστικά στοιχεία μιας πραγματικής τριφασικής μηχανής που προορίζεται για λειτουργία σε υδροηλεκτρικό σταθμό παραγωγής ενέργειας. Για την κατασκευή και εξομοίωση του μοντέλου στις δύο διαστάσεις χρησιμοποιήθηκε το λογισμικό Opera-2d, το οποίο χρησιμοποιεί την μέθοδο των πεπερασμένων στοιχείων, μια αριθμητική μέθοδο για να προσομοιώσει τη φυσική λειτουργία των ηλεκτρικών μηχανών. Για την επιτυχία του μοντέλου χρειάστηκαν αρκετές μετρήσεις και υπολογισμοί από τα δεδομένα που είχαμε τα οποία δεν παραθέτονται. Με την περάτωση του μοντέλου εξομοιώθηκαν διαφορετικές λειτουργίες στη μόνιμη κατάσταση για εξακρίβωση της ακρίβειας του μοντέλου που κατασκευάσαμε. Η διπλωματική εργασία χωρίζεται σε τέσσερα κεφάλαια. Στο πρώτο κεφάλαιο γίνεται μια αναφορά στις βασικές αρχές που διέπουν την κατασκευή και λειτουργία των σύγχρονων μηχανών και ειδικότερα τις τριφασικές σύγχρονες μηχανές με έκτυπους πόλους. Στο δεύτερο κεφάλαιο αναφέρουμε την θεωρία του ηλεκτρομαγνητισμού πάνω στην οποία βασίζονται οι υπολογισμοί που υλοποιούμε με την χρήση του Opera 2d. Αναλύουμε την μέθοδο των πεπερασμένων στοιχείων που χρησιμοποιούμε για να κάνουμε τους υπολογισμούς. Στο τρίτο κεφάλαιο κάνουμε μια σύντομη αναφορά στην θεωρία των σύγχρονων μηχανών για τις αμοιβαίες επαγωγιμότητες και αυτεπαγωγιμότητες του δρομέα και του στάτη. Στο τελευταίο κεφάλαιο παρουσιάζουμε τα πειράματα που διεξήγαμε για να υπολογίσουμε τις επαγωγιμότητες του στάτη και του δρομέα της σύγχρονης μηχανής. Στην τελευταία παράγραφο υπολογίζουμε κάποιες επαγωγιμότητες και αντιστάσεις με την βοήθεια αναλυτικών τύπων που βασίζονται στην θεωρία των σύγχρονων μηχανών και συγκρίνουμε τα αποτελέσματα με αυτά του κατασκευαστή. / This thesis was produced in the department of Electrical Engineering and Computer Science at the University of Patrai and involves the study of synchronous machine with salient pole and with the help of finite element analysis. The aim of the thesis is to calculate inductances of synchronous machine with salient pole. We will calculate mutual and self inductances of stator and rotor. To design the motor, machine data of a real motor, used to pump a storage hydroelectric generator, were used. The software Opera-2d was used to create the model in two dimensions. The software uses the finite element method to simulate the operation of electric machines. To ensure the motor design is suitable for the aim of the thesis, a number of measurements and calculations were made from the machine data which are not included as they are beyond the scope of this thesis. Also, after completing the model, simulations were run in steady state to verify that the model was running according to designed parameters. The thesis is structured in four chapters. Chapter 1 introduces the literature review where there is the principles regarding the construction and operation of synchronous machines and in particular three-phase synchronous machines with salient poles. In chapter 2, we refer to the theory of electromagnetism based on the calculations that we implement using the Opera 2d.We analyze finite element method which we use for calculations. In chapter 3, we make a brief reference to theory of synchronous machine for mutual and self inductances of rotor and stator. In the last chapter we present experiments we had to compute inductances of stator and rotor of synchronous machine. In last paragraph we compute some inductances and resistances with analytical formulas based on the theory of synchronous machine and compare our results with those of the manufacturer.
88

Efeitos de um progama de treinamento de caminhada livre e caminhada nórdica em idosos sedentários / Effects of a Nordic walking and free walking training program on static and dynamic balance parameters, self-selected walking speed, locomotor rehabilitation index and quality of life of sedentary elderly : a randomized controlled trial

Gomeñuka, Natalia Andrea January 2016 (has links)
Introdução: Considerando o rápido aumento da população de idosos e da sua expectativa de vida, junto com a expansão das intervenções de caminhada nórdica (NW) como método de treinamento para idosos, há uma necessidade de estudos de base experimental (ensaios clínicos randomizados controlados, ECRs) de caráter preventivo e de boa qualidade metodológica que permitam aos profissionais da educação física, da saúde e da reabilitação a tomada de decisões relativas ao tipo, volume, intensidade de exercício da NW na promoção da saúde dos idosos sedentários. Objetivos: o presente estudo teve como objetivos (estudo A) determinar, por meio de revisão sistemática de ensaios clínicos randomizados, se o treinamento sistematizado com NW, comparado à caminhada livre (CL), produz efeitos benéficos sobre componentes da aptidão funcional de idosos sedentários saudáveis, também avaliar (estudo B) os efeitos de oito semanas de treinamento de NW e CL na qualidade de vida (QV), no equilíbrio estático, na variabilidade dinâmica, na velocidade autosselecionada de caminhada (VAS) em esteira e no índice de reabilitação locomotor (IRL) de idosos sedentários, e também avaliar (estudo C) os efeitos de oito semanas de treinamento de NW e CL no trabalho mecânico (externo- Wext, trabalho mecânico interno- Wint, no trabalho mecânico total – Wtot), no mecanismo pendular (R), no Custo de transporte (C), na frequência cardíaca de exercício (FCexercício), na sensação subjetiva de esforço (RPE), e nos parâmetros eletromiográficos (amplitude média do sinal e co-contração) dos músculos: deltoides anterior (DA), tríceps braquial (TB), vasto lateral (VL), bíceps femoral (BF), tibial anterior (TA) e gastrocnêmio medial (GM) de idosos sedentários. Desenho Experimental: ECR. Local da Pesquisa: Escola de Educação Física, Fisioterapia e Dança (ESEFID) da Universidade Federal do Rio Grande do Sul Porto Alegre, Rio Grande do Sul, Brasil. Métodos: Participaram deste estudo 32 idosos sedentários randomizados em dois grupos (grupo NW), n=16, idade: 64,6±4,1 anos, massa: 81,5±10,7kg e estatura: 166,3±7,5cm; e o grupo CL, n=16, idade: 68,6±3,9 anos, massa: 74,6±14,5kg e estatura: 161,6±10,3cm), realizaram treinamento de NW e CL durante 8 semanas. Desfechos do estudo A: foram avaliadaos com um estudo de revisão sistemática parâmetros da aptidão funcional de idosos (força e resistência dos membros superiores, força e resistência dos membros inferiores, mobilidade, flexibilidade dos músculos da coluna lombar e da região posterior da coxa, amplitude geral da articulação do ombro, resistência aeróbia e velocidade autosselecionada). Desfechos do estudo B: foram avaliados utilizando questionário de qualidade de vida, testes de equilibrio em plataforma de força e coleta cinemática 3D durante caminhada em esteira rolante para determinação dos Parâmetros funcionais (qualidade de vida, equilíbrio estático e dinâmico, velocidade autosselecionada de caminhada e índice de reabilitação locomotor). Desfechos do estudo C: foram avaliados através coletas de dados espirométricos, cinemáticos 3D e eletromiográficos da caminhada em esteira rolante em diferentes velocidades os parâmetros mecânicos e do mecanismo pendular (trabalho mecânico externo, interno e total- Wext, Wint, Wtot, Recovery -R, Custo de transporte -C, Velocidade autosselecionada -VAS), parâmetros eletromiográficos (amplitude média do sinal e co-contração dos músculos DA, TB, VL, BF, TA e GM), frequência cardíaca de exercício – FCexercício, e sensação subjetiva de esforço - RPE, de idosos sedentários,. Análise Estatística: Os dados de descrição da amostra, no baseline, foram comparados aplicando-se ANOVA one-way. Os desfechos foram analisados utilizando as Equações de Estimativas Generalizadas (GEE), para a comparação entre os grupos (NW e CL) e os momentos (pré e pós treino). Utilizou-se um post-hoc de Bonferroni, para identificar as diferenças entre os efeitos e interações. Os dados foram apresentados em “model-based adjusted means”, e foram analisados com o software Statistical Package for the Social Science (SPSS) v.22.0. Adotou-se um nível de significância de α=0,05. Conclusão: os treinamentos de NW e de CL, promovem melhoras nos componentes da aptidão funcional; no equilíbrio estático e na variabilidade dinâmica de idosos. Contudo algumas diferenças entre as duas intervenções se relacionam ao princípio da especificidade do treinamento e ocorrem apenas nos componentes que receberam mais estímulos impostos pela técnica da caminhada com bastões, especialmente nos membros superiores. Ainda, o incremento da VAS na esteira aliada à utilização do IRL, nos permitem concluir que o treinamento de NW tem relevância clínica e é recomendado como meio de melhora do condicionamento físico e como método de reabilitação de idosos sedentários. Esta atividade física proporciona adaptações centrais com melhora significativa na mobilidade funcional de idosos. Deste modo, após treinamento de resistência aeróbica com e sem bastões os idosos aumentam a velocidade de locomoção nas atividades diárias e com menor custo metabólico devido às adaptações centrais e melhora do mecanismo pendular devido à maior proximidade da VAS à velocidade ótima de caminhada. Ainda há adaptações importantes na ativação muscular decorrentes do treinamento de NW em idosos indicando uma redução dos níveis de co-contração de membros superiores na caminhada sem bastões, à qual repercute diretamente na melhora da aptidão física, na independência funcional dos idosos. Além disso, recomendamos à NW como uma atividade física segura e efetiva para esta população quando a periodização do treinamento são realizados com o volume e intensidade estritamente controlados. / Introduction: Considering the rapid increase in the elderly population and their life expectancy, together with the expansion of Nordic walking (NW) interventions as a training method for the elderly, there is a need for experimental studies (randomized controlled trials, ECRs) of preventive character and of good methodological quality that allow the professionals of physical education, health and rehabilitation to make decisions regarding the type, volume and intensity of NW exercise in the health promotion of sedentary elderly. Objectives: This study aimed (study A) to determine, through a systematic review of randomized clinical trials, whether systematic training with NW, compared to free walking (FW), has beneficial effects on components of the functional capacity of sedentary elderly, also (study B) avaluate the effects of eight weeks of NW and FW training on quality of life (QoL), static balance, dynamic variability, self-selected walking speed on treadmill (SSWS) and Locomotor rehabilitation index (LRI) of sedentary elderly, and also evaluate (study C) the effects of eight weeks of NW and FW training on mechanical work (external, internal and total mechanical work -Wext,Wint, Wtot), pendular mechanism (R), Cost of (C), exercise heart rate (HRexercise), rate of perceived exertion (RPE), and electromyographic parameters (mean signal amplitude and co-contraction) of muscles: Anterior Deltoid (AD), Triceps Brachii (TB), Vastus Lateralis (VL), Femoral Biceps (BF), Anterior Tibialis (TA) and Medial Gastrocnemius (MG) of sedentary elderly. Experimental Design: Controlled Clinical Trial (ECR). Research Location: School of Physical Education, Physiotherapy and Dance (ESEFID), Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil. Methods: The sample comprised 33 sedentary participants randomly divided into two groups (NW group, n =16, age: 64.6 ± 4.1 years old, weight: 81.5 ± 10.7 kg and height: 166.3 ± 7.5 cm; and FW group, n =16, age: 68.6 ± 3.9 years, mass: 74.6 ± 14.5 kg and height: 161.6 ± 10.3 cm), performed NW and FW training for 8 weeks. Outcomes of Study A: Parameters of functional fitness of the elderly (upper limb strength and endurance, lower limb strength and endurance, mobility, lumbar spine and posterior hip muscle flexibility, general amplitude of the shoulder joint, aerobic endurance and self-selected speed). Outcomes of study B: Functional parameters (QoL, static and dynamic balance, SSWS and LRI).Outcomes of Study C: Mechanical parameters and pendular mechanism (Wext, Wint, Wtot, R, C, SSS), electromyographic parameters (mean signal amplitude and Co-contraction of AD, TB, VL, BF, AT and MG muscles), HRexercise RPE of sedentary elderly. Statistics Analysis: Sample description data, at baseline, were compared by applying one-way ANOVA. The outcomes were analyzed using Generalized Estimates (GEE), to compare the groups (NW and CL) and the moments (pre and post training). A Bonferroni post-hoc was used to identify the differences between effects and interactions. The data were presented in model-based adjusted means, and were analyzed with the software Statistical Package for the Social Science (SPSS) v.22.0. A significance level of α = 0.05 was adopted. Conclusion: NW and FW training, promotes improvements in functional fitness components; in the static balance and in the dynamic variability of the elderly. However, some differences between the two interventions are related to the principle of training specificity and occur only in the components that received the most stimuli imposed by the walking technique with poles, especially in the upper limbs. Furthermore, the increase in SSWS on the treadmill combined with the use of LRI allows us to conclude that NW training has clinical relevance and is recommended as a means of improving physical conditioning and as a method of rehabilitation of sedentary elderly. This physical activity provides central adaptations with significant improvement in the functional mobility of the elderly. Thus, after aerobic resistance training with and without poles, the elderly increase the speed of locomotion in daily activities and with lower metabolic cost due to the central adaptations and improvement of the pendulum mechanism due to the greater proximity of the SSWS to the optimal speed of walking. There are still important adaptations in muscle activation resulting from NW training in the elderly indicating a reduction in the levels of co-contraction of upper limbs in walking without walking poles, which directly affects the improvement of physical fitness and functional independence of the elderly. In addition, we recommend NW as a safe and effective physical activity for this population when the periodization of training is performed with the volume and intensity strictly controlled.
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Percepce Záolší očima polských menšinových médií. Analýza vybraných historických a společenských otázek Těšínského Slezska na základě textů Głosu Ludu a Zwrotu / Teschen Silesia through the Minority Media. Analysis of Selected Historical and Social Issues on the Regional Territory Based on Articles of Głos Ludu and Zwrot

Matelová, Táňa January 2018 (has links)
(in English): The diploma thesis analyzes special historical and social themes, which have been published in two most significant newspapers of Polish minority from Teschen Silesia - Głos Ludu and Zwrot. The theoretical part of this thesis is focused on problematics of Polish press in Teschen Silesia since 1848, especially on a history, contens and editors of first Polish- language newspapers. This part is also dedicated to the development of Polish press in Teschen Silesia in the 20th century, primarily to advancement of Polish press in the first half of the century, but also to the reaction to partition of Teschen Silesia after the First World War. This part put emphazis on Czech-Polish relations. The diploma thesis is also focused on the historical development and content of Głos Ludu and Zwrot (in the period of communism). Except for content analysis the thesis is dedicated to newspeak. The main purpose of the practical part of the thesis is to introduce a Polish perception of themself and perception of Czech majority through the minority press in the first six years after the fall of the communist regime (1990-1995). Using the Critical discourse analysis (CDA), the thesis examine a snippets of articles, which are divided into the following socio-historical thematic units: position of Polish...
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Otimização de traços de concreto : estudo aplicado a postes de concreto armado visando o aumento da vida útil / Optimization of concrete mixtures: study applied to reinforced concrete poles aiming to increase service life

Reginato, Lucas Alexandre January 2014 (has links)
A energia elétrica é, sem dúvida, um recurso indispensável para a sociedade moderna. A mesma revolucionou o modo de vida do ser humano em todos os aspectos e melhorou substancialmente sua qualidade de vida. A distribuição da energia elétrica cabe ao Sistema Elétrico de Potência – SEP, dividido basicamente em três macro setores: geração, transmissão e distribuição. A eletricidade é efetivamente entregue aos consumidores pelo sistema de distribuição, formado principalmente por redes aéreas sustentadas por postes, estes na sua maioria, feitos de concreto armado. Tendo em vista o adequado fornecimento da energia elétrica à sociedade, se faz necessário assegurar as linhas de distribuição de energia, na qual os postes exercem papel fundamental. Entende-se que o aumento da vida útil dos postes de concreto armado pode colaborar para a redução da manutenção da rede de distribuição, reduzindo o investimento em substituições ou reparos em postes por parte das concessionárias Deste modo, esse trabalho propõe a otimização do traço utilizado na produção de postes de concreto armado em uma empresa de artefatos de concreto, visando à vida útil do mesmo. Para tanto foram realizados estudos visando o aprimoramento da composição dos agregados, adição de material pozolânico, adição de fibras e utilização de aditivos superplastificantes. Para análise dos traços em escala real foram moldados 12 postes, tipo duplo T com 9 metros de comprimento, empregando 5 traços com características distintas. Os postes foram avaliados seguindo a metodologia e requisitos da NBR 8451-1 (ABNT, 2011), parâmetros de resistência mecânica do concreto e penetração de íons cloreto ASTM C1202 (2012). Por meio da análise dos resultados, é apresentado o traço indicado para produção de postes de concreto armado, onde foi possível aprimorar o traço atualmente produzido pela empresa, reduzindo o consumo de cimento de 429 kg/m³ para 351 kg/m³ e reduzindo a taxa de penetração de íons cloreto e aumentando a vida útil do poste de concreto armado de 10 para 60 anos. À vista disso, foi possível aumentar a vida útil do elemento, mesmo com a redução do consumo de cimento e o custo para a produção do traço de concreto. / Electricity is undoubtedly an indispensable resource for modern society. The same has revolutionized the way of life of the human being in all aspects and substantially improved their quality of life. The distribution of electricity is up to the Electric Power System - EPS, basically divided into three macro sectors: generation, transmission and distribution. Electricity is actually delivered to consumers by the distribution system, consisting mainly of overhead lines supported by pylons, these mostly made of reinforced concrete. Given the adequate supply of electricity to society, it is necessary to ensure the power distribution lines, in which the poles play a fundamental role. It is understood that increasing the useful life of reinforced concrete poles can contribute to the reduction of maintenance of the distribution network, reducing investment in replacements or repairs on poles by concessionaires. Thus, this paper proposes the optimal trait used in the production of reinforced concrete poles on a firm concrete artifacts, seeking the life of it For both studies were performed in order to improve the composition of households, adding pozzolanic material, adding fiber and use of superplasticizers additives. For analysis of traces in real scale 12 posts, T type double with 9 feet long, employing five traits were shaped with distinct characteristics. The posts were evaluated following the methodology and requirements of NBR 8451-1 (ABNT, 2011), the mechanical response of concrete and chloride ion penetration ASTM C1202 (2012). By analyzing the results, the dash indicated for production of reinforced concrete poles, where it was possible to improve the trace currently produced by the company, reducing the cement content of 429 kg / m³ to 351 kg / m³ and reducing the rate appears penetration of chloride ions and increasing the service life of reinforced concrete post 10 to 60 years. In view of this, it was possible to extend the life of the element, even with the reduction in cement consumption and the cost for the production of concrete mix.

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