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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.
41

Model profilu povrchu obrobku obrobeného válcovou obvodovou frézou / Model of surface profile after milling operation with plain milling cutter

Horváth, Ľudovít January 2014 (has links)
In the teoretical part of the master´s thesis, the master´s thesis deals with milling and surface profile describing. In the practical part, the master´s thesis deal with model of surface profile after milling operation with plain milling cetter. For evalution were used data obtained from the computer model of the surface profil and data obtained from measuring the actual surface profil, which was created by machining the material mills with a diameter of 45 mm.
42

Řezačka rohoží / Mat roll cutter

Šrámek, Michal January 2008 (has links)
The diploma thesis deals with the construction of a textile machine. More specifically, it deals with the construction of a vertical cutter of non-vowen fabrics that are made of polymerous fibres or fibre glass. The surface density of the material used ranges from 100 – 500 g/m2, the width of a role is 2000 mm and the weight is 150 kg. The machine is supposed to be designed in such a way so that the mat roles could be cut in any point.
43

Cutter head movement concept / Borrhuvudsförflyttningskoncept

Viberg, David January 2015 (has links)
This master thesis has been conducted at Svea Teknik on behalf of Atlas Copco and deals with the design of a cutter head motion system for mechanical rock excavation machines. Mechanical rock excavation allows tunneling to be done with just one machine in a continuous process. Such a machine is called a tunnel boring machine (TBM) and excavates rock by pressing a rotating cutter head with disc cutters against the rock face. By moving the cutter head in different patterns, tunnels of different profiles and sizes can be excavated. Atlas Copco has currently a conceptual TBM with an associated cutter head motion solution attached. The main task of this master thesis is to examine if an alternative solution to this motion system could be incorporated to the conceptual TBM, and to develop this solution to a functional concept design. In order to find a suitable alternative design nine concepts where generated and evaluated against the current concept solution using a weighted PUGH-matrix. The chosen concept was refined into a final functional concept design. The produced concept design consists of a two part linkage arm construction connected via a cylindrical joint. At one end of the articulated arm the cutter head is located and at the other end the linkage arm is connected to a rotatable base which allows the arm to rotate and swing to the sides. This rotatable base is in later turn supported by a base structure mounted to the main body of the current concept machine. All motion is achieved by hydraulic cylinders which are mounted in their respective ends using spherical bearings to minimize the need of narrow tolerance spans. The benefits of this alternative design are a greater choice of tunnel profiles along with simpler bearing solutions which may reduce manufacturing- and service costs. The downside is instead added weight to the front of the machine which will move the center of mass closer to the cutter head. This may have a negative effect on the machine propulsion system. / Detta examensarbete har utförts på Svea Teknik på uppdrag av Atlas Copco och behandlar utvecklingen av ett rörelsesystem för förflyttningen av borrhuvudet på maskiner för mekanisk bergavverkning. Med mekanisk bergavverkning är det möjligt att gräva ut en tunnel med bara en maskin i en kontinuerlig process. En sådan maskin kallas tunnelborrningsmaskin (TBM) och bryter berget genom att ett borrhuvud med brytskivor rullar under tryck mot bergsväggen. Genom att förflytta borrhuvudet i olika mönster kan tunnlar med olika profil och storlek anläggas. Atlas Copco har för närvarande en konceptuell TBM med tillhörande lösning för borrhuvudförflyttningen. Huvuduppgiften för detta examensarbete är att undersöka om en alternativ lösning till detta förflyttingssystem kan integreras med denna TBM och att utveckla den här lösning till en funktionell konceptdesign. För att hitta en lämplig alternativ utformning har nio koncept tagits fram vilka utvärderas mot den befintliga konceptlösningen i en viktad PUGH-matris. Det valda konceptet har förfinats till en slutgiltig funktionell konceptdesign. Det framtagna konceptet består av en tvådelad länkarmskonstruktion sammansatta via en cylindrisk rotationsled. I ena änden av länkarmen är borrhuvudet monterat och vid den andra änden är länkarmen ansluten till en roterbar bas som möjliggör att länkarmarna kan rotera och svänga åt sidorna. Denna roterande bas är i sin tur upphängd i en basstruktur som är fastmonterad på den nuvarande konceptmaskinen. All rörelse uppnås genom hydraulcylindrar som är monterade i respektive ände med hjälp av sfäriska lager för att minimera toleranskraven. Fördelarna med detta alternativa koncept är en större frihet i valet av tunnelprofiler tillsammans med en enklare lagerlösning som kan minska tillverknings- och servicekostnader. Nackdelen är istället att vikten längre fram på maskinen ökar. Detta leder till att masscentrum flyttats närmare borrhuvudet vilket kan ha negativ inverkning på maskinens framdrivningssystem.
44

Slezské řezané barokní sklo ve sbírce Uměleckoprůmyslového musea v Praze / Silesian Baroque Cut Glass in the collection of Museum of Decorative Arts in Prague

Bednářová, Tereza January 2012 (has links)
The Diploma thesis "Silesian Baroque Cut Glass in the collection of Museum of Decorative Arts in Prague" deals with the collection of Silesian Baroque cut glass at the Museum of Decorative Arts in Prague spanning from the last quarter of the 17th century to the third quarter of the 18th century. The thesis describes the technique of glass cutting and its history. It also deals with the beginnings of glass cutting in Silesia, which are associated with the Schaffgotsch family in the Hirschberger Valley. Worth mentioning is also the renowned glass cutter Friedrich Winter, who along with his glass workshop substantially influenced Silesian glass cutting in the following decades. The thesis also mentiones other well-known glass cutters, particularly Christian Gottfried Schneider. The chapters dealing with the development of the shape and ornament of Silesian Baroque cut glass are important for correct classification by periods and localities. A catalogue of selected objects from the collection of the Museum of Decorative Arts in Prague follows the first part of the thesis which comprises the text. Most of the catalogue's objects have not been published thus far or were often never presented in detail if they appeared in literature.
45

A Combined Field, Laboratory, and Numerical Study of Cutter Roof Failure inCarroll Hollow Mine, Carroll County, Ohio

Becker, James B. 18 June 2013 (has links)
No description available.
46

CWRU Cutter: Design and Control of an Autonomous Lawn Mowing Robot

Beno, Jonathan A. 17 May 2010 (has links)
No description available.
47

Ausarbeitung eines Finite-Elemente-Simulationsmodells für die Belastungen beim Kuttern und Optimierung diverser Kuttermesser mit bionischen Strukturen / Formulation of a finite-element-simulation model for the loads during the cutting process in a bowl cutter and optimization of various cutter blades with bionic structures

Morgenstern, Martin 08 May 2014 (has links) (PDF)
In der fleischverarbeitenden Industrie gibt es eine Vielzahl von Schneidwerkzeugen. Kuttermesser stehen hierbei in der Prozesskette weit hinten und haben einen direkten Einfluss auf die Qualität des Endprodukts. Der Prozess des Kutterns ist bislang nicht komplett analytisch geklärt. Während des Vorgangs durchläuft das Schneidgut (i.A. das Fleisch bzw. das Brät) wechselnde Aggregatzustände von fester (leicht gefrorener) Form hin zum zähviskosen Zustand. Weiterhin ist es permanentem korrosiven Kontakt ausgesetzt. Die Komplexität macht eine analytische Herangehensweise äußerst aufwendig, sodass sich mittels der FEM durch numerisches Vorgehen und Lastannahmen aus Untersuchungen diesem Problem gewidmet wird. Dabei sind bislang nicht bekannte Potentiale zu erkennen. Hierbei wurden verschiedene Vernetzungsstrategien (p- und h-Methode) der FEM angewandt und verglichen. Es sind dabei Materialreduktionen bis knapp 30% ersichtlich.
48

Descrição da atividade de forrageamento em Atta sexdens rubropilosa: transferência de informação e seleção de tarefas / Description of foraging activity in Atta sexdens rubropilosa: information sharing and task selection

Carmo, Daniele Victoratti do 10 February 2015 (has links)
As colônias de saúvas e o ambiente em que vivem são sistemas de dinâmica independente, variável e, ainda assim, interativos. Nesse sentido, frente às demandas flexíveis do ambiente, as tarefas que uma colônia deve executar devem ser acompanhadas da flexibilidade comportamental necessária. Para isso, a transmissão de informação, seja para forragear ou explorar novas áreas, deve ocorrer. Dentro deste contexto, o trabalho investigou em formigas do gênero Atta sexdens rubropilosa, o comportamento em um labirinto em Y. Foi observado um conjunto de comportamentos em duas condições experimentais: (1) com o corredor de acesso anterior à bifurcação do labirinto em Y marcado com feromônio e (2) corredor de acesso anterior à bifurcação do labirinto em Y não marcado com feromônio. Em ambos os casos um dos braços sempre estava marcado por feromônio e levava para a bandeja com folhas e outro não estava marcado e levava para uma bandeja sem folhas. Foi medido o fluxo em cada lado do braço após o Y, o número de formigas que permaneciam nas bandejas, o número de encontros de cabeça entre as formigas e o momento em que houve o primeiro transporte de folha. Observou-se o efeito no fluxo de formigas no labirinto entre as condições (1) e (2), e escolha do braço com e sem feromônio. Em uma ANOVA, comparando a permanência dos indivíduos antes e depois do primeiro transporte de folha encontrou-se efeito no braço (com x sem feromônio), e de interação entre lado (com x sem feromônio) e momento (antes x depois do transporte da primeira folha), e no número de encontros das formigas. Foi possível observar que: (1) as formigas que se engajaram na atividade de exploração do trecho limpo do corredor de acesso à bifurcação não alteraram a composição comportamental das formigas que passaram por ele, reforçando que o limiar exploratório naquela condição, de todas as formigas, parece não diferir; (2) a dinâmica de transmissão de informação nas áreas com e sem feromônio foram distintas e ocorreram de forma dinâmica. O transporte da primeira folha (3) atuou como um sinalizador da atividade que deveria ser priorizada naquele momento e a partir dele, havendo um maior fluxo, permanência e engajamento na atividade de forrageamento. Isso parece reforçar a concepção que mais que apenas entender como as formigas agem coletivamente na solução de um problema, é necessário compreender como coletivamente elas estabelecem os mecanismos de seleção de tarefas em condições que há tarefas concorrentes / The leaf-cutter ants colony and the enviromento in which they live are dinamically independent systems, variable and interactive. In this sense, opposite the flexible demands of the environment, the tasks a colony must perform could be accompanied by required behavioral flexibility. For this, the information transmission, whether to forager or explorer new area, it should occur. Within this context, this research investigated in leaf-cutter ants of the genus Atta, the behavior in a Y maze. The behavior was observed in two experimental conditions: (1) the previous access marked with pheromone to the bifurcation in the Y maze. (2) the previous access to the bifurcation in the Y maze without pheromone. In both cases one branch was always marked by pheromone and it led to the leaves box and other branch was unmarked and it led for a box without leaves. The flow was measured on each branch after the Y maze, the number of ants that remained in the trays was counted, the number of head-on encounter was counted and the moment the first leaf was transport. The effect on the ants flow was observed among the conditions (1) and (2). And the choose the branch without or with pheromone was encountered effect. In an ANOVA comparing the individuals permanence before and after the first leaf transported was observed effect on the arm (with X without pheromone), and interaction among branch side (with X without pheromone) and time (before X after the first leaf transported), and the number of head-on encounters. It was observed: (1) the ants engaged in exploration activity clean stretch of the previous acess to the bifurcation did not alter the behavioral composition of the others that passed there. It reinforcing the exploratory threshold in that condition, to all ants does not seem to differ; (2) the dynamics of information transmission in areas with and without pheromone were distinct and occurred dynamically. The first leaf transported (3) served as a marker of activity that should be prioritized at the moment and from there, with a greater flow permanence and engagement in foraging activity. This seems to reinforce the concept that more than just understanding how ants act collectively to solve a problem, it is necessary to understand how collectively they establish mechanisms for task selection in conditions that no competing tasks
49

O trabalhador do corte de cana no norte pioneiro do Paraná: o fim da atividade e os sentidos do trabalho

Rodrigues Filho, Luciano Ferreira 23 March 2015 (has links)
Made available in DSpace on 2016-04-29T13:31:16Z (GMT). No. of bitstreams: 1 Luciano Ferreira Rodrigues Filho.pdf: 5929443 bytes, checksum: d2ab604b02bedaba2bfd3ab1ca27ae12 (MD5) Previous issue date: 2015-03-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Sugar cane is part of the history of Brazil, and influence for social culture in the brazilian identity, was and is the raw material of important products for the country's economy, sugar and ethanol. However, in recent years, the cane fields of the country have been mechanized in harvesting and planting, resulting in decreased labor to cut sugar cane. This research aims to analyze the subjective dimensions and the meanings of work for cane cutting workers faced with the end of his activity in the Pioneer North of Paraná, where it applies to Resolution SEMA No. 076, of december 20, 2010 that provides for the "phasing out of straw removal of cane sugar by controlled burning" with this, the use of labor to cut sugar cane become unviable. Basing on the Socio-Historical Psychology, considering the subject is constituted in the dialectic relationship between the subject and the object, this research aims at understanding the subjective dimension, subjectivity - objectivity, for the constitution of cane cutting workers and thus understand the subject within a socio-historical context that changes. For this, outside held several conversations with rural workers, bookies, trade unionists and entrepreneurs to be able to know the determinants that mediate with the rural worker. Similarly, analyzing the socio-economic scenario of the country to understand the importance of sugar cane and the policy measures to the direction of workers and the production of sugar and ethanol. This made it possible to identify the end of the cane cutting activity occurred for the mechanization of sugarcane, but also by the current socio-economic context of the country that favors the migration of workers to other activities, however, the migration activity is not the end precarious work the sugarcane worker faces. The rural workers and their living conditions legitimized by capitalist ideology, are not as improvements to work, taking them to undergo other activities that pose risks to life and harms their health, thus, this dissertation contributes to clarify that the end a painful activity, does not guarantee improvements to the lives of workers in the same way that improvements in work conditions also are not guarantees of greater dignity at work, they often are camouflage mechanism and manipulate the expropriation of the worker / A cana de açúcar faz parte da história do Brasil, sendo influência para a cultura social na identidade brasileira, foi e é matéria prima de produtos importantes para a economia do país, o açúcar e o etanol. No entanto, nos últimos anos, os canaviais do país vêm sendo mecanizados em sua colheita e plantio, resultando na diminuição da mão de obra para o corte de cana. Esta pesquisa tem por objetivo analisar as dimensões subjetivas e os sentidos do trabalho para os trabalhadores do corte de cana frente o fim de sua atividade, no Norte Pioneiro do Paraná, onde se aplica a Resolução SEMA nº 076, de 20 de dezembro de 2010 que dispõe sobre a "eliminação gradativa da despalha da cana-de-açúcar através da queima controlada", com isto, a utilização da mão de obra para o corte de cana se tornam inviável. Pautando-se na Psicologia Sócio-Histórica, que considera o sujeito constituído na relação dialética entre o sujeito e o objeto, esta pesquisa visa compreender a dimensão subjetiva, subjetividade - objetividade, para a constituição do trabalhador do corte de cana e, assim, compreender o sujeito dentro de um contexto sócio-histórico que se modifica. Para isto, foram realizadas várias conversas com trabalhadores rurais, agenciadores, sindicalistas e empresários para ser possível conhecer os determinantes que fazem a mediação com o trabalhador rural. Do mesmo modo, analisando o cenário socioeconômico do país para compreender a importância da cana de açúcar e as medidas políticas para o rumo dos trabalhadores e da produção de açúcar e etanol. Com isto, foi possível identificar o fim da atividade do corte de cana ocorrido pela mecanização dos canaviais, mas também, pelo atual contexto socioeconômico do país que favorece a migração dos trabalhadores para outras atividades, no entanto, a migração de atividade não significa o fim do trabalho precário que o trabalhador canavieiro enfrenta. O trabalhador rural e sua condição de vida legitimada pela ideologia capitalista, não encontram melhorias quanto ao trabalho, tendo eles que se submeterem a outras atividades que oferecem riscos de vida e malefícios a sua saúde, com isto, esta dissertação contribui para esclarecer que o fim de uma atividade penosa, não garante melhorias à vida do trabalhador, da mesma forma que, melhorias na condição do trabalho também não são garantias de maior dignidade no trabalho, estas, muitas vezes, são mecanismo de camuflar e manipular a expropriação do trabalhador
50

"Amanhã é outro dia": falas, memórias e outras histórias de trabalhadores cortadores-de-cana em General Salgado SP, 1980 2008

Teixeira, Eber Mariano 25 March 2010 (has links)
Made available in DSpace on 2016-04-27T19:32:48Z (GMT). No. of bitstreams: 1 Eber Mariano Teixeira.pdf: 7534157 bytes, checksum: 14e8ee9c14301dc00e606ac531a10718 (MD5) Previous issue date: 2010-03-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present research aims to quest experiences of life for the workers sugar cane cutter at the General Salgado city, northwest region of São Paulo. The coming of these workers sugar cane cutter the field, and of other cities, mainly of the northeast region, represented new situations/tensions -, propagated for regional the local press/expressing and feeding reactions of different groups of the city, the region, ahead of the impact caused for this presence in the city. Searching to give visibility to the problematic ones lived by these workers, I look for to make a reflection in co-authorship with them, appealing to the ways as they interpret and they tell its experiences. Experiences that if they enunciate in the ways to work, to live, to socialize, in the proper forms of living, acting and interpreting the life, that we take and we analyze in ampler dimensions of the historical process. I searched to understand as these workers face, in the daily one, the processes of changes in the productive relations front to the mechanization of the sugar cane cut, the fight to guarantee the sustenance of the family -, as (re) they construct the convivial, (re) elaborate and internalize the values, customs, without losing of sight the tensions/social contradictions that produce and constitute in the spaces lived for the workers in its trajectories between the field and the city. From these questions placed in the present I started to reflect on the significant presence of the workers sugar cane cutter in General Salgado, disputing places and firming presence in the city in search of better conditions of life and work / A presente pesquisa problematiza as experiências vividas pelos trabalhadores cortadores-de-cana na cidade de General Salgado, região noroeste do Estado de São Paulo. A vinda destes trabalhadores cortadores-de-cana do campo e de outras cidades, principalmente da região nordeste, representou novas situações/tensões, veiculadas pela imprensa local/regional, expressando e alimentando reações de diferentes grupos da cidade, da região, diante do impacto causado por essa presença na cidade. Buscando dar visibilidade às problemáticas vividas por esses trabalhadores, procurei fazer uma reflexão em co-autoria com eles, recorrendo aos modos como interpretam e relatam suas experiências. Experiências que se enunciam nos modos de trabalhar, de morar, de sociabilizar, nas formas próprias de viver, agir e de interpretar a vida, que se toma e se analisa em dimensões mais amplas do processo histórico. Busquei compreender como estes trabalhadores enfrentam, no cotidiano, os processos de mudanças nas relações produtivas frente à mecanização do corte-de-cana, a luta para garantir o sustento da família , como (re) constroem convivências, (re) elaboram e internalizam valores, costumes, sem perder de vista as tensões/contradições sociais que engendram e constituem nos espaços vividos pelos trabalhadores em suas trajetórias entre o campo e a cidade. A partir dessas questões postas no presente é que comecei a refletir sobre a presença significativa dos trabalhadores cortadores-de-cana em General Salgado, disputando lugares e firmando presença na cidade em busca de melhores condições de vida e trabalho

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