Syfte – Syftet med examensarbetet är att minimera eller helt eliminera den utböjning som uppstår i Husqvarnas trimmer 536 LiR från handtag ner till motor och trimmerhuvud då en 5 kilos vikt hängs i handtaget. Metod – En konceptstudie har utförts på Husqvarnas trimmer 536 LiR för att undersöka och utvärdera hur problemet med trimmern ser ut i dagsläget och därifrån ta fram olika koncept för att minimera utböjningen. Arbetet har följt en Stage-Gate produktutvecklingsprocess med sju steg från att skriva kravspecifikation till att ta fram och testa prototyper. Koncept genererades med metoderna brainstorming och Reverse Engineering och sållades sedan med Pughs beslutsmatris. Finita elementmetoden användes för att utvärdera produkten och för att analysera vissa koncept. Avancerade prototyper skapades med selektiv lasersintring medan enklare modeller togs fram för hand. Prototyperna testades och jämfördes mot originalprodukten. Resultat – I detta arbete presenteras fem olika förslag för att minska utböjningen i trimmern; en förstyvning av plastkåporna på originalprodukten, tre tillbehör att fästa på den befintliga trimmern och ett förslag på materialbyte. Alla förslag gav positiva resultat med minskad utböjning, men Tillbehör 3 var det som visade sig minimera utböjningen mest och det enda som klarade av att möta syftet. Dock gav detta tillbehör för stort viktpåslag. Förstyvningen och materialbytet gav också bra resultat gällande utböjningen och ökade inte vikten för mycket. Implikationer – Om de förslag som presenteras här skulle implementeras och tas i produktion skulle det innebära vissa tillfälliga konsekvenser vid produktion av trimmern. Verktygen för plastdetaljerna skulle behöva ändras för förstyvningen och kanske också för materialbytet, medan det för de två första tillbehören skulle behöva tillverkas helt nya verktyg för formsprutning. För att implementera Tillbehör 3 skulle nya beräkningar behövas eftersom trimmerns egenfrekvens ändras. Det skulle dock vara billigare att tillverka detta tillbehör än de första två eftersom detta inte behöver formsprutas. Begränsningar – Flertalet av prototyperna framtagna i detta projekt är tillverkade med selektiv lasersintring och inte med formsprutning, som är tillverkningsmetoden för de nuvarande plastkåporna. Detta innebär att hållfasthetsegenskaperna inte är desamma som de skulle bli vid verklig produktion. Dessutom är materialen som används glasfiberfyllda, vilket innebär att hållfastheten kommer att påverkas ytterligare beroende på tillverkningsmetod. Glasfibrernas positioner och riktningar blir olika vid olika processer vilket ger upphov till olika egenskaper. / Purpose – The purpose of this thesis is to minimize or completely eliminate the flexure in Husqvarna’s brush cutter 536 LiR from the handle down to the engine and the blade when a weight of 5 kilogrammes is hanged from the handle. Method – A concept study has been made on Husqvarna’s brush cutter 536 LiR to examine and evaluate what the problem with the model is and from that to develop different concepts to minimize the flexure. The work has followed a Stage-Gate product development process with seven steps from defining the specification of requirements to developing and testing prototypes. Ideas of concepts were generated using the methods brainstorming and Reverse Engineering and were later sifted using Pugh’s matrix. Finite Element Analysis was used to evaluate the product and to analyse certain concepts. Advanced prototypes were created using selective laser-sintering whilst simpler models were created by hand. The prototypes were tested and compared to the original product. Findings – This project presents five different suggestions on how to minimize the flexure in the brush cutter; one stiffer version of the original plastic casings, three accessories to attach to the original product and a proposal for a change of material. All these suggestions gave positive results with a lesser flexure, but the third accessory, Tillbehör 3, was the one that showed the smallest flexure and the only one able to fulfil the purpose of the study. The weight of the accessory was, however, too big. The stiffer version of the original casings and the change of material also showed good results regarding flexure and did not increase the weight too much. Implications – If any of the proposals of this project were to be implemented in production, it would cause certain temporary consequences for the production of the brush cutter. The tools for the plastic components of the current brush cutter would need some changing in order to manufacture the stiffer version of the mouldings or to produce the different material, whilst for the first two accessories completely new tools for injection moulding would have to be developed. To implement the third accessory, new calculations would be needed since the eigenfrequency of the brush cutter would be changed. It would, however, be cheaper to produce this accessory compared to the first two, since the third one does not need to be manufactured using injection moulding. Limitations – Most of the prototypes in this work is manufactured using selective laser sintering and not injection moulding, which is the manufacturing method of the current plastic casings. This means that the properties of the materials will be different than they would be if they were manufactured for production. Furthermore the materials used in the casings of the brush cutter are filled to certain degree with glass fibres, meaning that the material properties will be even more different depending on manufacturing method. The position and direction of the glass fibres will be different depending on which process is used, giving different mechanical properties.

A tool path generation method for sculptured surfaces defined by triangular meshes is presented in this thesis along with an algorithm that helps determine the best type of cutter geometry to machine a specific surface. Existing tool path planning methods for sculptured surfaces defined by triangular meshes require extensive computer processing power and result in long processing times mainly since surface topology for triangular meshes is not provided. The method presented in this thesis avoids this problem by offsetting each triangular facet individually. The combination of all the individual offsets make up a cutter location surface. A single triangle offsetting results in many more triangles; many of these are redundant, increasing the time required for data handling in subsequent steps. To avoid the large number of triangles, the proposed method creates a bounding space to which the offset surface is limited. The original surface mesh describes the bounding surface of a solid, thus it is continuous with no gaps. Therefore, the resulting bounding spaces are also continuous and without gaps. Applying the boundary space limits the size of the offset surface resulting in a reduction in the number of triangular surfaces generated. The offset surface generation may result in unwanted intersecting triangles. The tool path planning strategy addresses this issue by applying hidden-surface removal algorithms. The cutter locations from the offset surface are obtained using the depth buffer. The simulation and machining results show that the tool paths generated by this process are correct. Furthermore, the time required to generate tool paths is less than the time required by other methods. The second part of this thesis presents a method for selecting an optimal cutter type. Extensive research has been carried out to determine the best cutter size for a given machining operation. However, cutter type selection has not been studied in-depth. This work presents a method for selecting the best cutter type based on the amount of material removed. By comparing the amount of material removed by two cutters at a given cutter location the best cutter can be selected. The results show that the optimal cutter is highly dependent on the surface geometry. For most complex surfaces it was found that a combination of cutters provides the best results.

The credit card industry is huge with over two and a half billion cards shipped annually. A local card manufacturer, with a production volume in excess of forty million cards annually, approached the University of Canterbury to design and develop advanced card manufacturing technology. The motivation behind this development was the desire of the sponsoring company to keep abreast of new technologies and to have the ability to manufacture and supply cards with this new and emerging technology into a highly competitive world market. This thesis reports the research surrounding the development of a dedicated new machine tool explicitly designed to implement the emerging technologies found in the international credit card industry. The machine tool, a dedicated milling machine, was not developed in its entirety within these pages; however, three major constituents of the machine were researched and developed to a point where they could be implemented or become the subject of further research. The three areas of interest were; • A machine table system that avoided the increased zonal wear to which linear bearings are subject, typically due to short high frequency traversals, and also the high friction and mass generally found in dovetail slides. • Design requirements demanded the use of a single commercially available carbide cutter to produce 1500 components per hour. Therefore, a purpose built high (revs per minute) rpm spindle and drive system specifically for use with polymeric materials, (R-PVC in particular) was deemed necessary. • Tracking the cutter depth in relation to an RFID aerial track embedded within the credit card core. The aerial tracking was to be dynamic and occur during the machining process with the machine “remembering” the depth of cut at contact with the aerial. Each of the three areas was researched via an in-depth literature review to determine what and if any material had been published in these fields. For the development of the machine table a novel flexure hinge idea was considered. Considerable material was discovered about flexures, but very little was found to be relevant to the application of high displacement metal flexures necessary to meet the required levels of table movement. In effect the proposed machine table system and research in this field would be novel. The high performance spindle investigation became directed into a much narrower focus as it progressed; that of determining the power consumption required to machine the integrated circuit pockets in an R-PVC work piece. This was due to the lack of information pertaining to the physical properties of polymeric materials, in particular the specific cutting pressure. The depth following sensor array was configured using capacitance detection methods to determine the distance between the cutter?s end and the aerial tracks. Capacitance sensing methods, whilst not new, were developed into a novel arrangement to meet the specific cutter tracking requirements of the proposed new machine tool. Each of the respective development areas had concept designs completed and were prototyped before being tested to determine the effectiveness of the respective designs. The outcomes from the testing are reported herein, and show each constituent part to be basically feasible, in the application. The results were sufficient to indicate that each development showed distinct potential but further development and integration into the machine tool should ensue.

This thesis examines the pedagogical value of a particular visual programming environment (VPE) called the Gem Cutter which is based upon the functional programming paradigm. The contribution of this thesis is two-fold: it provides a qualitative evaluation via the Cognitive Dimensions Framework developed by Green to explore the usefulness of the Gem Cutter environment from a pedagogical viewpoint, and secondly provides a framework called the Word Game Framework designed in the Gem Cutter which can be used to create exercises for sudents learning to program. The Word Game Framework allows students to create interactive turn-based "wordgames" and provides an engaging environment for students to explore interesting and useful functional programming concepts such as recursion, higher order functions, type inference, and list processing.

Orientador: Mariângela Spotti Lopes Fujita / Banca: João Batista Ernesto de Moraes / Banca: Mariângela Pisoni Zanaga / Resumo: A Catalogação de Assunto (Subject Cataloging) é um dos processos de representação temática da informação e foi desenvolvida nos Estados Unidos a partir da consolidação da Biblioteconomia estadunidense e dos processos biblioteconômicos que evidenciaram a necessidade de maior desenvolvimento dos catálogos, pois estes se afirmaram como instrumento indispensável às bibliotecas e suas comunidades usuárias. No entanto, a despeito de o Brasil ter sido fortemente influenciado pela Biblioteconomia estadunidense, há pouca literatura nacional a seu respeito e assim, pouca discussão dos aspectos históricos, conceituais e metodológicos da Catalogação de Assunto. Assim, abordamos esses aspectos por meio de estudo teórico e também da obra de Charles A. Cutter, nome fundamental para a evolução da Catalogação, e dos princípios propostos em sua obra Rules for a Dictionary Catalog. Dessa maneira, tivemos por objetivo auxiliar na compreensão desses fundamentos acerca da Catalogação de Assunto e conceder subsídios teóricos que pudessem contribuir para a diminuição da carência desse tema em língua portuguesa. A partir disso, realizamos o percurso histórico da Catalogação de Assunto partindo de seu contexto mais amplo, que é a Catalogação como um todo, e o desenvolvimento da própria biblioteconomia estadunidense. Em seguida, discutimos o conceito de "assunto", dada a sua importância e constante presença no vocabulário da área e na própria expressão Catalogação de Assunto. Utilizamos o método do Protocolo Verbal em Grupo, para buscar a visão de acadêmicos e profissionais acerca das discussões aqui levantadas e dessa forma, obter dados sobre o conhecimento dessas questões nessas duas esferas de atuação, a partir do que confirmamos que embora tais tópicos tenham tido pouco espaço entre a literatura brasileira, e assim, é necessário que esta abordagem seja... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Subject Cataloging is a process of thematic representation of the information and was developed in the United States from the consolidation of the american librarianship and of the librarian processes that evidenced the need for further development of catalogs, as they asserted themselves as an instrument indispensable to libraries and their user communities. However, despite Brazil having been heavily influenced by American Library, there is little national literature about and so little discussion of historical, conceptual and methodological aspects of Subject Cataloging. Thus, we addressed these aspects through theoretical study and also the work of Charles A. Cutter, fundamental name to the evolution of Cataloging, and the principles proposed in his Rules for a Dictionary Catalog. Thus, we had by objective was to assist in understanding these fundamentals about Subject Cataloging and provide theoretical support that could contribute to reducing the lack of this theme in Portuguese. From this, we outline the history of the Subject Cataloging departing from its broader context, which is Cataloging as a whole, and the development of American librarianship. Next, we discuss the concept of "subject", given its importance and constant presence in the vocabulary of area and in the expression Subject Cataloging. We used the method of Think-aloud protocol, to seek the view of academics and professionals about the discussions raised here and thereby obtain data on the knowledge of these issues in these two spheres of activity, from which we confirm that although these topics have been little space between the Brazilian literature, and so, it is necessary that this approach is carried out to seek of the understanding of this conceptual universe. We conclude so far that actually there is a dearth of literature in Portuguese, to guide the epistemological foundation pillars for the Subject...(Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2015-03-26T13:42:20Z (GMT). No. of bitstreams: 1 texto completo.pdf: 409832 bytes, checksum: ad0a607cdb6347db88136cb73c5389f8 (MD5) Previous issue date: 2011-02-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This is the first genetic study on Atta robusta to investigate the genetic variability and structure in populations from Espírito Santo and Rio de Janeiro in which microsatellites specific primers were used. Twenty microsatellite primers for A. robusta were designed and eleven (55%) were polymorphic. When analyzing 80 colonies of A. robusta, the number of alleles/locus ranged from 7 to 24. The observed heterozigosity ranged from 0,27 a 0,80 in the loci analyzed, meanwhile the expected heterozigosity ranged from 0,30 to 0,83. When grouping the colonies within the two targeted populations (Espírito Santo and Rio de Janeiro), it was confirmed that they are genetically similar. In the population from Espírito Santo, the number of alleles/locus ranged from 6 to 22. The observed heterozigosity ranged from 0,22 to 0,70, while the expected heterozygosity ranged from 0,30 to 0,85. In the population from Rio de Janeiro, the number of alleles/locus ranged from 4 to 17. The observed heterozigosity ranged from 0,32 to 0,97, while the expected ranged from 0,29 to 0,81. However, when considering the colonies sampled in each of the 16 localities as a subpopulation, it was confirmed that they are highly structured. However, the UPGMA analysis did not provide accurate evidence that the formation of clades containing only colonies are geographically nearby. When considering the 80 colonies sampled, they weren’t structured and did not group colonies geographically adjacent. These results indicate that the colonies of A. robusta sampled either in Rio de Janeiro or Espírito Santo have high genetic variability and that they aren’t structured. Although, considering the endemism and the threaten to extinction of A. robusta, in order to conserve this species will be necessary the maintenance of all possible colonies in the Restinga’s region. / Este é o primeiro estudo genético realizado com Atta robusta e investigou a variabilidade genética e o nível de estruturação nas populações do Espírito Santo e Rio de Janeiro com o uso de primers microssatélites espécie-específicos. Assim, vinte primers microssatélites específicos para A. robusta foram desenhados, sendo que onze (55%) foram polimórficos. Ao se analisar 80 colônias de A. robusta, o número de alelos/loco variou de 7 a 24. A heterozigosidade observada variou de 0,27 a 0,80 nos locos analisados, enquanto a esperada variou de 0,30 a 0,83. Agrupando-se as colônias em duas populações (Espírito Santo e Rio de Janeiro), verificou-se que elas são geneticamente similares. Na população do Espírito Santo, o número de alelos/loco variou de 6 a 22. A heterozigosidade observada variou de 0,22 a 0,70 nos locos analisados, enquanto a esperada variou de 0,30 a 0,85. Na população do Rio de Janeiro, o número de alelos/loco variou de 4 a 17. A heterozigosidade observada variou de 0,32 a 0,97 nos locos analisados, enquanto a esperada variou de 0,29 a 0,81. Por outro lado, considerando-se as colônias amostradas em cada uma das 16 localidades amostradas, como uma subpopulação, verificou-se que elas estão altamente estruturadas. Apesar disto, a análise de agrupamento não evidenciou a formação de clados contendo apenas colônias de localidades geograficamente próximas. Por outro lado, quando se considerou as 80 colônias amostradas, não se verificou estruturação e nem agrupamento de colônias de acordo com a localidade de origem das mesmas. Em conclusão, os resultados obtidos indicam que as colônias amostradas, tanto no Rio de Janeiro como no Espírito Santo, apresentam alta variabilidade genética e que as mesmas não estão estruturadas. Entretanto, considerando-se o endemismo e a ameaça à extinção de A. robusta, para conservá-la será necessário a manutenção do maior número possível de colônias nas regiões de restinga destes dois Estados.

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-07-23T19:23:55Z No. of bitstreams: 1 Dissertação Lidia - 0412.17doc (003).pdf: 1798159 bytes, checksum: 5a60beb26c5f7be125eb337773512792 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-30T21:25:29Z (GMT) No. of bitstreams: 1 Dissertação Lidia - 0412.17doc (003).pdf: 1798159 bytes, checksum: 5a60beb26c5f7be125eb337773512792 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-30T21:29:13Z (GMT) No. of bitstreams: 1 Dissertação Lidia - 0412.17doc (003).pdf: 1798159 bytes, checksum: 5a60beb26c5f7be125eb337773512792 (MD5) / Made available in DSpace on 2018-07-30T21:29:25Z (GMT). No. of bitstreams: 1 Dissertação Lidia - 0412.17doc (003).pdf: 1798159 bytes, checksum: 5a60beb26c5f7be125eb337773512792 (MD5) Previous issue date: 2018-03-12 / O milho (Zea mays L.) utiliza a hibridação como o principal processo de produção de sementes. Neste, ocorre a eliminação da inflorescência masculina das plantas genitoras femininas para que ocorra o cruzamento com os polinizadores conhecidos como genitores masculinos. O despendoamento mecânico pode ser realizado por arranque dos pendões, sendo realizado por um equipamento mecânico denominado “Wheel Puller’ (pneu) ou “Cutter” (faquinha). O objetivo deste trabalho foi avaliar a eficiência de três métodos diferentes de despendoamento mecânico em campos de produção de sementes híbridas de milho. O experimento foi realizado na safra 2016/2017, em área de produção localizada no município de Indianapolis-MG e foram avaliados três tipos de despendoamento, os quais constituíram os tratamentos: T1 (“puller”), T2 (“cutter 2 vezes + puller”) e T3 (“cutter 1 vez + puller”). Foram mensurados: número de folhas acima da espiga, umidade na colheita, umidade após secagem, peso líquido das espigas no campo, peso líquido das espigas após a secagem, rendimento de debulha, peso líquido de sementes debulhadas, rendimento na pré-limpeza, sementes limpas para classificação, e massa de 1000 sementes. Os tratamentos T2 e T3 obtiveram melhores resultados em relação ao número de folhas acima da espiga, o que pode ter influenciado também em melhores valores de peso líquido de espiga e rendimento na usina. No entanto, não houve diferença significativa entre os tratamentos em relação a umidade de colheita e peso de mil grãos. / The maize (Zea mays L.) hybridization is the main process of seed production, in which the objective is the elimination of the male inflorescence of the female genitor plants so that the crossing occurs with the pollinators known as male genitors. Mechanical detassaling can be performed by pulling the tassels which is done by a mechanical equipment called Wheel Puller (tire) or by Cutter (slides). The objective of this work is to evaluate three different mechanical detasseling methods in corn hybrid seed production. The experimente was carried out in the 2016/2017 harvest in a seed production field in Indianapolis-MG and was evaluated three detasseling methods, which the treatments consisted of: T1 (“puller”), T2 (“cutter 2 times + puller”) e T3 (“cutter 1 time + puller”). It was measured: number of leaves above the ear corn, harvesting moisture, ear moisture after drying, ear corn weight in the field, ear weight after drying, shelling yield, shelled seeds weight, pre-cleaning yield, clean seeds for classification, and 1000 seeds. Treatments T2 and T3 had better results in number of leaves above the ear corn, which might have influenced in better results for ear corn weight and yield. Although there was no significant difference between treatments concerning harvesting moisture and 1000 seeds weight.

The dredging activity is increasing worldwide due to ships that require bigger drafts, and consequently deeper navigation channels. Some dredging projects requires the operation of cutter suction dredgers on open waters, once these are capable of removing compact sediments and rocks while still maintaining a good productivity. These facts motivated the creation of a weather driven downtime prediction software for this type of operation, based on simplified calculations of the main dredging systems of a CSD. The motions caused by waves, and the forces and moments caused on these dredgers by winds, waves and currents were analyzed in order to evaluate the influence of each parameter magnitude and direction on the behavior of the vessel. The main criteria of the dredger influenced by this conditions were determined by a literature review as being the swing winch required power, the interaction between the cutterhead and the soil, and the anchoring system resistance, this that can be both a spud pole system stress or the Christmas tree cable tension. In this research, only the spud pole system bending stress was considered. Three mathematical models were developed to represent those systems. Since the non-linearity of the relation between the reaction forces of the dredger and the soil was not an object of the study, this process is represented by a constant user defined reaction force and a horizontal cutterhead velocity model. The efficiency of these models were tested by applying them on a case study of the dredging of the Açu port on the Brazilian coast by the Taurus II dredger. Simultaneous wind, wave and current data data were used as input to these models by creating a time series scenario of the operation period. The results for both scenarios showed that the operation would be close to impossible due to wave generated dynamic stress on the spud pole. / A atividade de dragagem no mundo é cada vez mais significativa em função do aumento dos navios que operam em portos, estes que possuem maior calado e requerem, consequentemente, canais de navegação mais profundos. Alguns projetos de dragagem utilizam dragas de sucção e recalque em mar aberto, dada a capacidade destes equipamentos de remover sedimento compactado e rochas, ainda mantendo uma boa produtividade. Estes fatos motivaram a criação de um programa de previsão de downtime gerado por condições ambientais de dragas de sucção e recalque baseado em modelos matemáticos simplificados. Os movimentos causados por ondas, e as forças e momentos causados na draga por ventos, ondas e correntezas foram analisados de forma a se obter a influência da magnitude e direção de cada um destes parâmetros no comportamento da embarcação. Os principais sistemas da draga influenciados por estas condições foram determinados com base em uma revisão bibliográficas como sendo a potência requerida nos guinchos de varredura, a interação do cortador com o solo e a resistência do sistema de ancoragem, sendo este a tensão de flexão dinâmica na trave do spud ou as tensões de ancoragem pelo sistema de árvore de natal. Três modelos matemáticos foram desenvolvidos para representar estes sistemas. Considerando a não linearidade da interação entre a draga e o solo, este processo foi representado por uma força de reação definida pelo usuário e pela velocidade horizontal do cortador. A eficiência destes modelos foi testada ao aplicá-los em um estudo de caso da dragagem do porto de Açu, na costa brasileira pela draga Taurus II. Valores simultâneos de ondas, ventos e correnteza foram utilizadas como entrada nestes modelos, através da criação de um cenário hipotético de série temporal. Os resultados para ambos os casos demonstraram que a operação seria impossibilitada em função de tensões de flexão dinâmicas no spud maiores que o limite determinado.

This thesis deals with the application of the methodology LEAN and TOC to solve the problem of low capacity of fabric cutting machine. The aim of the thesis is to apply LEAN and TOC methodology to propose solutions for continuous improvement of cutting process. To solve the problem itself is used mainly principle of five focusing steps, which is based on the theory of constraints and which is described in the theoretical part of the thesis. The theoretical part also introduces some methods and tools of lean management, which are already in place in the company BOS Automotive Products CZ, s.r.o, also their specific applications are demonstrated. During research was identified a potential source of continuous improvement. This source are data that constantly sends cutter during operation. In conclusion are summarized results and suggestions for improvement based on the used principles and recommendations for further improvement.

This diploma thesis consists of two parts. The theoretical part describes sintered carbides, their properties and manufacturing tools. Some selected problems of milling and its physical nature is discussed also. It also deals with the types and methods of tool wear testing. The aim is to compare the experimental properties of monolithic end milling cutters (short four cutting edges, uncoated carbides) of various grain sizes in two basic ways of milling - down-feed method and up-feed method. The measured values are evaluated by analysis in time series of the cutting forces and power.