Dissertations / Theses on the topic 'Experimental Drawing'

Tree Drawings have been used extensively in software engineering and many other business and computer applications. The basic structure of a tree allows for the organization and representation of complex information. Many commercial tools allow their users to draw or construct trees to represent a problem and/or its solution. Our focus is on dynamic trees - trees subject to frequent changes and redisplay in highly user-friendly interactive computer applications. Tree presentations in such interactive tools have to be precise and maintainable, which means, the tree presentations should maintain a particular structure so that user's mental perception of the tree is not disrupted or changed drastically when modifications are made to the tree being manipulated. Minimal modifications to the tree should cause correspondingly minimal changes to the general layout of the tree drawing and such changes should be consistent with the original layout to enable the user to anticipate them and verify their correctness with minimal mental effort. Also, display properties, like Vext, Hext, aspect ratio and space utilization efficiency of the layout are important to the user as they influence efficient use of available drawing/visualizing space which in turn affects comprehensibility of the tree drawing in question. In this thesis report, we analyze and compare three published algorithms, proposed by Workman-Bernard[1], S. Moen[3], and R. Cohen [2],to interactively manage the layout of graphically represented dynamic trees. We attempt to measure and analyze the performance of these algorithms based on their layout properties and their computational requirements. This research concludes that the Workman-Bernard (WB) algorithm when compared with its closest equivalent, Moen's algorithm, produces trees with better layout at a significantly lower computation cost.
M.S.
School of Computer Science
Engineering and Computer Science
Computer Science

UNIVERSIDADE CATÓLICA DE PETRÓPOLIS
Esta pesquisa visa ao desenvolvimento de um protótipo de traçadora gráfica, para desenhar sobre uma superfície rígida na posição vertical. A principal aplicação desta traçadora é no segmento de comunicação visual para anúncios em grandes superfícies. Com a intenção de atingir alto grau de flexibilidade nesta utilização, a traçadora é concebida para trabalhar em coordenadas polares, dispensando um quadro fixo composto de várias guias lineares como seria o caso de uma traçadora x, y. Numa primeira parte, apresenta-se o layout básico, a construção do protótipo e as equações cinemáticas que governam o movimento. Em seguida, é feita uma análise estática da traçadora e do momento máximo requerido para movimentar o braço, visando à correta especificação dos atuadores. Com base nas equações geométricas utilizadas, foi elaborado um algoritmo de traçado que contempla as não linearidades inerentes ao problema.Vários testes com figuras geométricas foram realizados, para a avaliação do protótipo.
The present research aims the development of an experimental prototype of a plotterdesigned to work on a vertical plane. In order to achieve maximum flexibility to work on site, the plotter was conceived to operate in polar coordinates with a single fixed point.This concept simplifies transportation and assemblage of the plotter at the working location. The work discusses the kinematical equations for pen displacent, static and dynamic equation for torque evaluation as well as some design challenges which had to be overcome in order to make the plotter operational and reliable. Experimental results concerning precision and drafting velocity are presented in the work and final comments on further design improvements of the plotter are discussed in the last part.

Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2018.
Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2018.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages [39]-42).
One way to study how people design is to understand how others observe them designing. I take a step towards this understanding by examining how people segment visual design events temporally, in other words, how they divide these events into smaller pieces. I developed a methodology to comparatively study how multiple observers segment design events. In order to test my methodology, I conducted an experiment. In this experiment, I compared different attributes of a design event to see if some attributes communicate more meaning than others. From the results of the experiment, I observed that the segmentation of the design event was affected more by the gestures of the designer than by the produced designs. My observations suggest computational principles that could be used to develop computational design assistants that better understand designers intentions.
by Ege Ozgirin.
S.M.

Trefilação é um dos processos de fabricação para a obtenção de arames, tubos e barras. Este processo consiste na redução da área de seção transversal de um material cilíndrico, fazendo-o atravessar uma matriz cônica de menor seção de área transversal, chamada fieira. Destacam-se o excelente acabamento superficial, a boa precisão dimensional e o aumento na resistência mecânica do material como vantagens e, como desvantagens, deformações heterogêneas ocorrem quando atravessam a ferramenta de trefilação (fieira). As deformações heterogêneas provocam retorno elástico também heterogêneo das camadas da barra trefilada, o que induz o aparecimento das tensões residuais relacionadas às distorções de forma, empenamentos e variações dimensionais, causando desperdício de material e energia, tanto no caso de geração de refugo, quanto em tentativas de correção das não conformidades. Desta forma, neste trabalho estudou-se a influência da geometria da fieira no valor da força necessária para realizar a trefilação e no gradiente das tensões residuais em barras de aço, através de experimentos físicos e computacionais. Após a caracterização de um processo de trefilação de um aço SAE 1045 foram desenvolvidos modelos computacionais no software Simufact.forming GP ®, e obtidos os resultados para: a força de trefilação, as tensões residuais das direções principais, as deformações plásticas, o limite de escoamento e o retorno elástico do material após a realização do processo para uma determinada redução. Os modelos foram validados através da comparação dos resultados simulados com experimentos físicos e equações encontradas na literatura. Após a validação, o modelo computacional foi utilizado para simular a variação da geometria da fieira: número de regiões de trabalho, raios de convergência entre as diferentes regiões da ferramenta, diferentes materiais e áreas de seção transversal. Os resultados das simulações computacionais foram correlacionados e utilizados para projetar e fabricar uma fieira em escala reduzida e um dispositivo mecânico para a simulação física do processo de trefilação em uma máquina universal de ensaios Emic ®. Duas diferentes geometrias de fieira foram testadas experimentalmente F1: a fieira convencional, e F4, a fieira modificada a partir das sugestões obtidas a partir da metodologia escolhida para correlacionar os resultados das simulações computacionais. As novas barras trefiladas foram caracterizadas mecanicamente através de ensaios de microdureza e rugosidade para análise das propriedades mecânicas, difração de raios-X para obtenção das tensões residuais superficiais e força de trefilação, que foi medida durante a realização do ensaio. Este trabalho contribuiu cientificamente com uma melhor compreensão do comportamento do escoamento de um material trefilado e através da análise de uma nova geometria de fieira que permitiu uma redução no valor das tensões residuais, um pequeno aumento na força de trefilação, mantendo as propriedades mecânicas do material trefilado quando comparadas com o processo original objeto desta pesquisa.
The wire drawing is a manufacturing process used to produce wires, tubes and rods. It consists in a reduction in cross sectional area by plastic deformation where the raw material (wire rod) is pulled through a die. Some of the main features of the wire drawing process are the achievement of an excellent surface finishing and good dimensional accuracies and increase in mechanical strength. However, this process generates inhomogeneous deformation due to the different flowing of the material into the drawing tool (die). The inhomogeneous deformation generates residual stress, stresses present in a material free from the action of external loads and temperature gradients. Residual stresses are commonly related to distortions of shape and dimensional variations of the final products, appearing after heat treatments which are related to shape distortions, warping and dimensional variations, causing material and energy waste, in the case of waste generation and in attempts to correct nonconformities. Thus, the influence of die geometry to reducing the residual stresses and the drawing force of bars manufactured by a cold-drawing process was studied. After the characterization of a drawing process of an SAE 1045 steel, computer models were developed in the software Simufact.forming GP ®, and the results were obtained for: drawing force, residual stresses of the main directions, plastic deformations, flow and the elastic return of the material after the process was carried out. The models were validated by comparing simulated results with physical experiments and equations found in the literature. Different die geometries were simulated as: number of tool regions, fillets between different tool regions, different materials and cross-sectional areas. The results of the computational simulations were correlated and used to design and manufacture a scale die and a mechanical device to develop the physical drawing tests in an Emic ® testing machine. Two different die geometries were experimentally tested F1: the conventional die, and F4, the modified from suggestions obtained in the computational simulations correlation F. The mechanical characterization of the new drawn bars were carried out by Vickers microhardness and roughness tests, X-ray diffraction to obtain surface residual stresses and the drawing force was taken during the test. This work contributes scientifically with a better understanding of the behavior of the flow of a drawn material by the analysis of a new die geometry that allowed a reduction in the value of the residual stresses, an increase in the drawing force and maintaining the mechanical properties of the drawn material when compared to the original process object of this research.

This thesis confronts the ultimate limits of perceiving the constructed world and the limits of our ability to experience architecture. The imperative of architecture is poetic: to and project encounters between matter and energy that shape the existing and bring forth the as yet unimagined to form a continuing human world. This is explored through the imagining of a habitat and vessel that projects the human endeavor of architecture into the formless depth of space. In drawing the physical from the void, the page becomes a way to move architecture from non-existence into the real by means of the imagination. An imagined wold is drawn from the void in search of the center for a universal and humanist architecture. The thesis is conceived as a vehicle for drawing the limits of perception when we attempt to imagine that which is greater than ourselves.
Master of Architecture

The aim of this diploma thesis is experimental testing and evaluation of the suitability of lubricants for drawing stainless chromium - nickel austenitic steel X5CrNi18-10 and comparison of the results obtained from the work [51]. The testing was performed by modeling the friction between the traction edge and the retainer, which corresponds to the real production process at ACO Industries. The introductory part of the thesis describes the process of deep drawing, followed by a description of tribology and the effect of friction. The individual types and properties of lubricants are described in more detail. The main part of the work deals with the testing of lubricants. The results are then described and evaluated.

The goal of this research is to investigate the combined effects of glass fibre reinforcement and molecular orientation in polypropylene-short glass fibre composites. Specimens have been fabricated using the injection moulding process and drawn using a small die drawing rig. The effects of die drawing on the fibre composites are complex, with the drawing process orienting both the polymer molecules and the glass fibres. This may be accompanied by the creation of voids in the polymer matrix and their destruction in the compressive stress field thus restoring the interfacial contact area between fibre and matrix. Unfilled and short glass fibre filled polypropylene specimens, with fibre content 7% wt, 13%wt, 27%wt, and 55%wt, were injection moulded prior to the die drawing process. An experimental program of die drawing within an oven at elevated temperature was conducted for polypropylene filled to various levels and at different strain rates. The specimens drew to draw ratios in the range ¿=1.41 to ¿=5.6. Mechanical characterization of the test materials has been conducted by examining the tensile stress strain and fracture behaviour under uniaxial conditions. The influence of glass fibre content and drawing conditions (draw ratio) on the fracture toughness and crack propagation was investigated using the double edge notched fracture test. The notch lengths ranged from 1.5 to 2.5 mm for 10 mm wide specimens. The critical stress intensity factor increased as the fibre content increased up to a limiting filler level. The fracture toughness of both unfilled and fibre filled polypropylene were found to be highly dependent on draw ratio. The results were analysed to find out the optimal draw ratio and fibre content that yielded the maximum modulus, strength and fracture toughness. Data showed that, at a given draw ratio, modulus, strength and fracture toughness increased with increasing fibre content to a maximum and then decreased. The optimum material was obtained at a draw ratio of 2.5 and filler loading 13wt%.

The goal of this research is to investigate the combined effects of glass fibre reinforcement and molecular orientation in polypropylene-short glass fibre composites. Specimens have been fabricated using the injection moulding process and drawn using a small die drawing rig. The effects of die drawing on the fibre composites are complex, with the drawing process orienting both the polymer molecules and the glass fibres. This may be accompanied by the creation of voids in the polymer matrix and their destruction in the compressive stress field thus restoring the interfacial contact area between fibre and matrix. Unfilled and short glass fibre filled polypropylene specimens, with fibre content 7% wt, 13%wt, 27%wt, and 55%wt, were injection moulded prior to the die drawing process. An experimental program of die drawing within an oven at elevated temperature was conducted for polypropylene filled to various levels and at different strain rates. The specimens drew to draw ratios in the range γ=1.41 to γ=5.6. Mechanical characterization of the test materials has been conducted by examining the tensile stress strain and fracture behaviour under uniaxial conditions. The influence of glass fibre content and drawing conditions (draw ratio) on the fracture toughness and crack propagation was investigated using the double edge notched fracture test. The notch lengths ranged from 1.5 to 2.5 mm for 10 mm wide specimens. The critical stress intensity factor increased as the fibre content increased up to a limiting filler level. The fracture toughness of both unfilled and fibre filled polypropylene were found to be highly dependent on draw ratio. The results were analysed to find out the optimal draw ratio and fibre content that yielded the maximum modulus, strength and fracture toughness. Data showed that, at a given draw ratio, modulus, strength and fracture toughness increased with increasing fibre content to a maximum and then decreased. The optimum material was obtained at a draw ratio of 2.5 and filler loading 13wt%.

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Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq
The Human Figure drawing is a tool widely considered and used in the area of Psychology. There are many controversies regarding its form of interpretation and its validity of the emotional indicators presented by the test. The objective of this study was to investigate the evidences of validity of the Human Figure Drawing (HFD) as an emotional measure. The sample consisted of 310 children, 173 of the regular group, 82 of the clinical group and 55 of the regular / problem group. The regular group comprised of children attending public elementary schools, the clinical group for children attended by two private clinics in the State of S?o Paulo, coming from both public school and private school, and the regular group / problem by school children indicated by those responsible as having behavioral problems, but did not go through psychological care. The instruments used were: Identification card elaborated by the researcher, DFH evaluated by the system of emotional difficulties, Multidimensional Scale of Life Satisfaction for Children (EMSVC) and Positive Affect Scale and Negative. Data were analyzed through Pearson's Correlation, Multivariate Analysis of Variance (MANOVA) and Analysis of Variance (ANOVA). The results indicated that the variable group was significant only for the emotional indicators in the HFD. The correlations between the emotional indicators in the HFD were negative as expected between the total female figure and the positive self factor of the infant life satisfaction scale (r = -, 174; p?0.01), and with the factor of positive school (r = -, 161; p?0.01). In the total of the male figure, similar significant relationships were found, with positive self factors (r = -, 176, p?0.01) and positive schooling (r = -, 173; p?0.01). In the positive and negative affect scale only the sex/group interaction in the fact of negative affect had a significant influence (F=3,367; p?0,05), and in the income variable in Negative affect (F=3,978; p?0,01). In the Multidimensional Scale of Life Satisfaction for Children and in the Positive and Negative Affect Scale, we can see that the results are affected by income, that is, contextual indicators. It is concluded that the emotional HFD screening system is a valid measure and can be used in children's psychodiagnosis.
O desenho da Figura Humana ? uma ferramenta considerada altamente difundida e utilizada na ?rea da Psicologia. H? muitas controv?rsias em rela??o a sua forma de interpreta??o e sua validade dos indicadores emocionais apresentados pelo teste. O objetivo deste estudo foi de investigar as evid?ncias de validade do Desenho da Figura Humana (DFH) enquanto medida emocional. A amostra foi composta por 310 crian?as sendo 173 do grupo regular, 82 do grupo cl?nico e 55 do grupo regular/problema. O grupo regular formado por crian?as que frequentavam escolas p?blicas do Ensino Fundamental, o grupo cl?nico por crian?as atendidas por duas cl?nicas particulares do Estado de S?o Paulo, provenientes tanto de escola p?blica como de escola particular, e o grupo regular/problema por crian?as de escola p?blica indicadas por seus respons?veis como portadoras de problemas de comportamento, mas n?o passavam por atendimento psicol?gico. Os instrumentos utilizados foram: Ficha de identifica??o elaborada pela pesquisadora, DFH avaliado pelo sistema de dificuldades emocionais, Escala Multidimensional de Satisfa??o de Vida para Crian?as (EMSVC) e Escala de Afeto Positivo e Negativo. Os dados foram analisados por meio da Correla??o de Pearson, An?lise Multivariada da Vari?ncia (MANOVA) e An?lise de Vari?ncia (ANOVA). Os resultados encontrados indicaram que a vari?vel grupo foi significativa somente para os indicadores emocionais no DFH. As correla??es entre os indicadores emocionais no DFH foram negativas significativas como era esperado entre o total da figura feminina com o fator do eu positivo da escala satisfa??o de vida infantil (r=-,174; p?0,01), e com o fator de escola positiva (r=-,161; p?0,01). No total da figura masculina foram encontradas rela??es significativas semelhantes, com os fatores do eu positivo (r=-,176, p?0,01) e escola positiva (r=-,173; p?0,01). Na Escala de afeto positivo e negativo somente a intera??o sexo/grupo no fato de afeto negativo teve influ?ncia significativa (F=3,367; p?0,05), e na vari?vel renda no Afeto Negativo (F=3,978; p?0,01). Na Escala Multidimensional de Satisfa??o de Vida para Crian?as e na Escala de Afeto Positivo e Negativo, nota-se que os resultados s?o afetados pela renda, ou seja, indicadores contextuais. Conclui-se que o sistema de triagem do DFH emocional ? uma medida v?lida e pode ser utilizada no psicodiagn?stico infantil.

The aim of work is to present and analyse assessment of the current state and at the same time the proposal of adjustments to the technology or parameters, the introduction of the wire into the drawing machine. The problem arises when the introduction of wire with a diameter of 14 mm from the material CK 67 to the drawbenches Schumag. If we introduce the wire into the drawing machines with two primary beams leads to a buckling of the wire and pack between the drawing die and the boot device. For the introduction of wire are used hydraulic boot collets, which are controlled semi-automatically. In connection with professional studies and on the basis of the calculation, simulation and practical experiment have been identified the conditions allowing the current method of deployment of wire to use.

Els documents gráfics són documents que expressen continguts semántics utilitzant majoritáriament un llenguatge visual. Aquest llenguatge está format per un vocabulari (símbols) i una sintaxi (relacions estructurals entre els símbols) que conjuntament manifesten certs conceptes en un context determinat. Per tant, la interpretació dun document gráfic per part dun ordinador implica tres fases. (1) Ha de ser capadçe detectar automáticament els símbols del document. (2) Ha de ser capadç extreure les relacions estructurals entre aquests símbols. I (3), ha de tenir un model del domini per tal poder extreure la semántica. Exemples de documents gráfics de diferents dominis són els planells darquitectural i d’enginyeria, mapes, diagrames de flux, etc. El Reconeixement de Gráfics, dintre de lárea de recerca de Análisi de Documents, neix de la necessitat de la indústria dinterpretar la gran quantitat de documents gráfics digitalitzats a partir de laparició de lescáner. Tot i que molts anys han passat daquests inicis, el problema de la interpretació automática de documents sembla encara estar lluny de ser solucionat. Básicament, aquest procés sha alentit per una raó principal: la majoria dels sistemes dinterpretació que han estat presentats per la comunitat són molt centrats en una problemática específica, en el que el domini del document marca clarament la implementació del mètode. Per tant, aquests mètodes són difícils de ser reutilitzats en daltres dades i marcs daplicació, estancant així la seva adopció i evolució en favor del progrés. En aquesta tesi afrontem el problema de la interpretació automática de documents gráfics a partir dun seguit de models relacionals que treballen a tots els nivells del problema, i que han estat dissenyats des dun punt de vista genèric per tal de que puguin ser adaptats a diferents dominis. Per una part, presentem 3 mètodes diferents per a lextracció dels símbols en un document. El primer tracta el problema des dun punt de vista estructural, en el que el coneixement general de lestructura dels símbols permet trobar-los independentment de la seva aparença. El segon és un mètode estad ístic que aprèn laparença dels símbols automáticament i que, per tant, sadapta a la gran variabilitat del problema. Finalment, el tercer mètode és una combinació dambdós, heretant els beneficis de cadascun dels mètodes. Aquesta tercera implementaci ó no necessita de un aprenentatge previ i a més sadapta fácilment a múltiples notacions gráfiques. D’altra banda, presentem dos mètodes per a la extracció del context visuals. El primer mètode segueix una estratègia bottom-up que cerca les relacions estructurals en una representació de graf mitjançant algorismes dintel_ligència artificial. La segona en canvi, és un mètode basat en una gramática que mitjançant un model probabilístic aprèn automáticament lestructura dels planells. Aquest model guia la interpretació del document amb certa independència de la implementació algorísmica. Finalment, hem definit una base del coneixement fent confluir una definició ontol`ogica del domini amb dades reals. Aquest model ens permet raonar les dades des dun punt de vista contextual i trobar inconsistències semántiques entre les dades. Leficiència daquetes contribucions han estat provades en la interpretació de planells darquitectura. Aquest documents no tenen un estándard establert i la seva notació gráfica i inclusió dinformació varia de planell a planell. Per tant, és un marc rellevant del problema de reconeixement gráfic. A més, per tal de promoure la recerca en termes de interpretació de documents gráfics, fem públics tant les dades, leina per generar les dades i els evaluadors del rendiment.
Graphical documents express complex concepts using a visual language. This language consists of a vocabulary (symbols) and a syntax (structural relations among symbols) that articulate a semantic meaning in a certain context. Therefore, the automatic interpretation of these sort of documents by computers entails three main steps: the detection of the symbols, the extraction of the structural relations among these symbols, and the modeling of the knowledge that permits the extraction of the semantics. Different domains in graphical documents include: architectural and engineering drawings, maps, flowcharts, etc. Graphics Recognition in particular and Document Image Analysis in general are born from the industrial need of interpreting a massive amount of digitalized documents after the emergence of the scanner. Although many years have passed, the graphical document understanding problem still seems to be far from being solved. The main reason is that the vast majority of the systems in the literature focus on a very specific problems, where the domain of the document dictates the implementation of the interpretation. As a result, it is difficult to reuse these strategies on different data and on different contexts, hindering thus the natural progress in the field. In this thesis, we face the graphical document understanding problem by proposing several relational models at different levels that are designed from a generic perspective. Firstly, we introduce three different strategies for the detection of symbols. The first method tackles the problem structurally, wherein general knowledge of the domain guides the detection. The second is a statistical method that learns the graphical appearance of the symbols and easily adapts to the big variability of the problem. The third method is a combination of the previous two inheriting their respective strengths, i.e. copes the big variability and does not need of annotated data. Secondly, we present two relational strategies that tackle the problem of the visual context extraction. The first one is a full bottom up method that heuristically searches in a graph representation the contextual relations among symbols. Contrarily, the second is syntactic method that models probabilistically the structure of the documents. It automatically learns the model, which guides the inference algorithm to counter the best structural representation for a given input. Finally, we construct a knowledge-based model consisting of an ontological definition of the domain and real data. This model permits to perform contextual reasoning and to detect semantic inconsistencies within the data. We evaluate the suitability of the proposed contributions in the framework of floor plan interpretation. Since there is no standard in the modeling of these documents, there exists an enormous notation variability and the sort of information included in the documents also varies from plan to plan. Therefore, floor plan understanding is a relevant task in the graphical document understanding problem. It is also worth to mention that, we make freely available all the resources used in this thesis (the data, the tool used to generate the data, and the evaluation scripts) aiming at fostering the research in graphical document understanding task.

Sheet metal forming has an important place among metal forming processes. As the usage of sheet metal increases, the fatigue simulation and optimization of these parts become more important. This thesis study examines the change of the fatigue life of a sheet metal part after forming. A sphere-like shape is deep drawn and change in thickness and residual stresses are analyzed. To understand the effect of residual stresses, deep drawn parts with and without residual stress tested against the fatigue failure. In parallel, the forming process is simulated with an implicit finite element method (FEM). The success of forming simulation is discussed in the study. Thickness changes and residual stresses calculated with FEM are included in computer aided fatigue analysis. The effect of thickness changes is examined with the results of FEM analysis. The effectiveness of the whole simulation process is discussed by comparing the outputs of experiments and computational analysis.

L'évolution de la microstructure de films de poly(éthylène téréphtalate) (polymère thermoplastique amorphe et cristallisable) a été étudiée lorsqu'ils sont soumis à un traitement mécanique (mono ou bi-étirage) et à un traitement thermique. L'étirage est effectué entre les températures de transition vitreuse et de cristallisation. A partir d'une valeur critique du taux d'étirage (2,8), il apparaît une phase cristalline induite. L'évolution de la texture cristalline a été étudiée par diffraction des rayons X (Debye-Scherrer et figures de pôles). Les chaines s'orientant selon la/les direction/s d'étirage, les figures de pôles montrent le développement d'une forte texture de fibres. De plus, dans le cas des films bi-étirés, les plans cristallins les plus denses s'orientent parallèlement aux faces des films. Dans tous les cas, la taille des cristaux induits par l'étirage est plus petite que celle des sphérolites initiés par le chauffage. Les différents films ont été étudiés par analyse enthalpique différentielle, analyse mécanique dynamique et courants de dépolarisation thermostimulés. Il a été mis en évidence l'existence d'une phase supplémentaire mésomorphe (à partir d'un taux d'étirage égal à 2). Cette phase amorphe rigide prend naissance dans la phase amorphe. Elle est transformée en une phase cristalline anisotrope si le matériau subit une contrainte mécanique ou thermique supplémentaire. L'analyse thermique des films pré-cristallisés par étirage, ayant des taux d'étirage inférieurs à 4,2, montre l'existence d'une cristallisation supplémentaire initiée par la chaleur. L'influence de l'étirage sur la topologie de la phase amorphe a également été étudiée. Nous avons mis en évidence l'existence de deux relaxations apparaissant a des températures inférieures à la température de transition vitreuse. L'analyse par courants de dépolarisation thermostimulés montre que l'augmentation du taux d'étirage s'accompagne d'une localisation de la mobilité moléculaire

Snapover is particularly relevant to Earth-orbiting spacecraft powered by high-voltage solar arrays. During snapover, the current collected by a positively biased conductor that is immersed in a plasma suddenly increases when two conditions are met: i) there is an immediately adjacent insulator; ii) the conductor exceeds a positive threshold voltage with respect to the plasma. The enhanced current develops as a consequence of the insulator, either through secondary electron (SE) emission or by material ionization. Experiments were performed to examine snapover onset potential and current collection dependence on conductor and insulator materials, conductor size and shape, sample history, biasing rate, and contamination and smoothness of the dielectric surface. Numerous current jumps were observed between applied voltages of 100 V and 1000 V. Both surface roughening and surface coatings were found to inhibit snapover. In general, the results did not support previous simple interpretations of the SE model.

Resumo: O objetivo deste trabalho foi investigar e modelar matematicamente a influência das variáveis do processo de têmpera e revenimento no limite de resistência à tração de arames de aço trefilado SAE 9254 com diâmetros de 2,00mm e 6,50mm. Para isso, utilizaram-se as ferramentas estatísticas de delineamento de experimentos e de regressão múltipla com aplicação de análise de componentes principais. Os resultados revelaram quais variáveis do processo têm influência significativa na variável resposta. Os modelos matemáticos obtidos pela regressão múltipla predizem com boa precisão a propriedade mecânica limite de resistência à tração.
Abstract: The purpose of this work was to investigate and to model mathematically the influence of the quench hardening and draw tempering process variables on the tensile strength of SAE 9254 drawn steel wires with 2,00 mm and 6,50mm diameter. To this end, the statistical tools of design of experiments and multiple regression with application of principal components analysis were employed. The results revealed the process variables that significantly affect the response variable. The mathematical models obtained by multiple regression were able to predict, with a reasonable accuracy, the mechanical property of the tensile strength.
Orientador: Messias Borges Silva
Coorientador: Rosinei Batista Ribeiro
Banca: Marco Antonio Carvalho Pereira
Banca: Gilbert Silva
Mestre

Etude concernant le comportement predateur de la sepiole realisee en combinant les observations en milieu naturel et en aquarium. L'analyse qualitative et quantitative de l'acte de predation a permis de definir 3 phases distinctes: "alerte", "positionnement" et "capture". Une etude sur le choix alimentaire a ete egalement realisee, elle montre que les sepioles semblent preferer les mysidaces

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo deste trabalho foi investigar e modelar matematicamente a influência das variáveis do processo de têmpera e revenimento no limite de resistência à tração de arames de aço trefilado SAE 9254 com diâmetros de 2,00mm e 6,50mm. Para isso, utilizaram-se as ferramentas estatísticas de delineamento de experimentos e de regressão múltipla com aplicação de análise de componentes principais. Os resultados revelaram quais variáveis do processo têm influência significativa na variável resposta. Os modelos matemáticos obtidos pela regressão múltipla predizem com boa precisão a propriedade mecânica limite de resistência à tração.
The purpose of this work was to investigate and to model mathematically the influence of the quench hardening and draw tempering process variables on the tensile strength of SAE 9254 drawn steel wires with 2,00 mm and 6,50mm diameter. To this end, the statistical tools of design of experiments and multiple regression with application of principal components analysis were employed. The results revealed the process variables that significantly affect the response variable. The mathematical models obtained by multiple regression were able to predict, with a reasonable accuracy, the mechanical property of the tensile strength.

In vielen Anwendungen sind Papier und Karton wegen der hohen Verfügbarkeit, überlegenen Umformbarkeit und der hervorragenden Barriereeigenschaften von Kunststoffen verdrängt worden. Die Akzeptanz von Verpackungen aus erdölbasierten Kunststoffen nimmt jedoch auf Grund der Probleme hinsichtlich Recyclings, Anreicherung von Mikroplastik in den Meeren und Deponierung ab. Folglich steigt der Druck auf Industrie und Wissenschaft, nachhaltige Verpackungslösungen mit Packstoffen aus nachwachsenden Rohstoffen zu entwickeln und einzusetzen. Auf Grund dieser Entwicklungen müssen die Grenzen für die Einsetzbarkeit von Papier und Karton in anspruchsvollen Verpackungslösungen neu betrachtet werden. Mit dem Umformprozess 'Ziehen von Karton' können komplexe dreidimensionale Verpackungskomponenten hergestellt werden. Allerdings wird der Prozess von diversen Material- und Prozessparametern, sowie Umweltbedingungen beeinflusst und erfordert daher systematisches Vorgehen bei Prozessanalyse und Optimierung. Ziel dieser Arbeit war die Analyse von Einflussparametern des Ziehprozesses mit experimentellen und simulativen Methoden. Dazu ist die Entwicklung von objektiven und automatisierten Messmethoden zur Erfassung von Qualitätskriterien der Ziehteile notwendig. Unter Anwendung der entwickelten Messmethoden wurden die Einflüsse von Prozessparametern auf die Umformung untersucht. Es wurden Messmethoden zur Bestimmung von Lage und Anzahl der für den Ziehprozess charakteristischen Falten und für die Messung der Formabweichung entwickelt. Darüber hinaus wurde eine statistische Analyse zum Auftreten von Materialversagen während der Umformung durchgeführt. Die experimentellen Untersuchungen zeigten, dass sowohl das Auftreten von Rissen, als auch die Faltenbildung vornehmlich durch die Faltenhalterkraft beeinflusst werden. Jedoch können Faltenbildung und Formabweichung durch Erhöhung der eingebrachten thermischen Energie über Beheizung der Werkzeuge verbessert werden. Der Energieeintrag konnte durch Erhöhung von Werkzeugtemperaturen und durch Reduktion der Stempelgeschwindigkeit erfolgen. Im simulativen Teil der Arbeit wurde die Anwendbarkeit der Finite Elemente Methode (FEM) auf die Simulation des Ziehprozesses untersucht. Simulationen des Einlaufvorgang des Materials in die Ziehbüchse mit einem für die Abbildung von Karton entwickelten Materialmodell, welches Orthotropie, elastisch-plastisches Verhalten und die Wirkung von Temperatur auf die mechanischen und tribologischen Eigenschaften enthielt, ergaben, dass die Stempelkraftkurve in diesem Prozessabschnitt gut abgebildet werden konnte. Darüber hinaus wurde die Anwendbarkeit von FEM-Modellen zur Simulation der Faltenbildung untersucht. Untersuchungen des Einflusses von Werkzeugtemperaturen auf die mechanischen Eigenschaften und Reibeigenschaften ergaben, dass sich Variationen in der Kraftkurve nur durch die Reduktion des Reibkoeffizienten bei erhöhter Werkzeugtemperatur ergaben. Die Erweichung des Materials durch Erhöhung der Temperatur führte dagegen nicht zu Variationen der Kraftkurve im Einlaufvorgang.:DANKSAGUNG III KURZFASSUNG IV TABLE OF CONTENTS VI LIST OF ABBREVIATIONS IX LIST OF SYMBOLS X LIST OF FIGURES XII LIST OF TABLES XV 1 INTRODUCTION 1 1.1 Background 1 1.2 Research problem 2 1.3 Objectives and outline of the thesis 3 2 LITERATURE REVIEW 4 2.1 Forming of paperboard 4 2.1.1 Categorization of forming processes 4 2.1.2 Hydroforming 6 2.1.3 Pressforming 7 2.1.4 Deep drawing of paperboard 7 2.1.4.1 Deep drawing process 7 2.1.4.2 Quality criteria and measurement 10 2.1.4.3 Scientific advances in deep drawing 11 2.2 Mechanical properties of paper and paperboard 14 2.2.1 Microstructure of paper and paperboard 14 2.2.2 Tensile behavior 16 2.2.3 In-plane compression 17 2.2.4 Yield stress and plastic deformation 18 2.2.5 Mechanical behavior in ZD 19 2.2.6 Rupture of paperboard 20 2.2.7 Friction 21 2.2.8 Inhomogeneity 22 2.2.9 Influence of environmental conditions on paperboard properties 24 2.2.9.1 Influence of moisture content 24 2.2.9.2 Influence of temperature 25 2.2.9.3 Effects of environmental conditions on mechanical properties 26 2.3 Modeling of paperboard 28 2.3.1 Fundamentals of modeling 28 2.3.1.1 Classification of models 28 2.3.1.2 Elastic modeling 29 2.3.1.3 Elastic-plastic modeling 31 2.3.1.4 Out-of-plane modeling 33 2.3.2 FEM Material models 34 2.3.3 Modeling of moisture and temperature 36 2.3.4 Modeling of fracture 39 2.3.5 Modeling of friction 41 2.4 Applications of models for paper and paperboard 42 2.4.1 Simulations of packaging components and processing steps 42 2.4.2 Simulation of creasing and folding 42 2.4.3 Simulation of hydroforming 44 3 EXPERIMENTAL PROCESS ANALYSIS 46 3.1 Shape accuracy analysis 46 3.1.1 Measurement method 46 3.1.2 Validation 48 3.1.3 Experimental conditions 50 3.1.4 Results 51 3.1.4.1 Parametric study 51 3.1.4.2 Influence of heat energy transfer 55 3.1.4.3 Relationship between shape accuracy and transferred heat energy 58 3.2 Analysis of wrinkling 62 3.2.1 Method 62 3.2.2 Validation 64 3.2.3 Results 65 3.2.3.1 Influence of material properties on wrinkling 65 3.2.3.2 Parametric study 66 3.2.3.3 Relationship between wrinkling and transferred heat energy 71 3.3 Rupture in deep drawing 73 3.3.1 Method 73 3.3.2 Results 77 4 SIMULATIVE PROCESS ANALYSIS 84 4.1 Explicit FEM analysis 84 4.1.1 Modeling 84 4.1.1.1 FEM-model 84 4.1.1.2 Material model 88 4.1.1.3 Modeling of temperature effects 92 4.1.2 Calibration 93 4.1.3 Validation 94 4.1.4 Results 96 4.1.4.1 Punch force 96 4.1.4.2 Analysis of stresses in deep drawing 101 4.1.5 Limitations for FEM-models 106 4.2 Global model 109 4.2.1 Material model 109 4.2.1.1 Mechanical behavior 109 4.2.1.2 Wrinkling model 110 4.2.1.3 Inhomogeneity 112 4.2.2 Modeling of environmental influence 113 4.2.3 Friction model 114 4.2.4 Rupture model 115 5 CONCLUSIONS 117 REFERENCES 121 INDEX TO APPENDICES 140 APPENDIX 141

碩士
國立虎尾科技大學
工業工程與管理研究所
102
Now technology is increasingly developed, experiments in various domains are increasingly complex, thus relatively experimental cost and time used are increasingly getting higher, so the study aims at using Taguchi method applied to experiment for synthetic fiber process to reduce experiment times and enhance experimental efficiency. The study takes acrylic strand hot drawing process as example, applies Taguchi orthogonal table to experimental process, by means of setting control factors and levels, to evaluate their importance of effect in acrylic strand hot elongation process, and considering interaction effect among factors, so that accuracy of experimental prediction can be enhanced, and further conducts small range experiment with evaluated experimental combinations, to find out possible preferred parameter combinations in the process, thereby effect of reducing experimental cost can be achieved. The study considers interaction effects among factors, the prediction results in the study has enhanced prediction accuracy comparing to that of interaction effects among factors not considered. From experiment, it is found that prediction with interaction effects among factors considered is more accurate, the same experimental results of 30 times of experiments are the same as results of 48 time, through the experiments, it is found that Taguchi method is capable of effectively enhancing experimental efficiency, reducing experiment cost, and thereby it can be provided for reference in experiments of other processes in synthetic fiber processing plants.

碩士
國立屏東科技大學
技職教育研究所
103
This study discussed the effect on students’ academic achievement by integrating teaching for creative thinking into beauty and colored painting curriculum. In this study, the subjects were 94 students(7 male students and 86 female students) from two second-year classes of a beauty department of S vocational school in Kaohsiung City to conduct experimental teaching. The experimental group was focused on teaching for creative thinking, while the control group was focused on the general traditional teaching. The questionnaires collection, analysis and qualitative data, like reviews summary, students’ creative works and students’ feedback sheet on thoughts were used to understand students’ academic achievement in the beauty and colored painting. In terms of quantized questionnaire data, this study found that the students’ satisfaction scores in the three aspects of skill acquisition, knowledge acquisition and teaching behavior in the experimental group are significantly higher than those of control group. In terms of qualitative data, this study analyzed and accepted students’ academic achievement in three kinds of colored painting techniques of point, line and surface in the experimental teaching of beauty and colored painting, as well as teachers’ teaching characteristics perceived by students during the process of experimental teaching of beauty and colored painting. Based on the above results, several suggestions are proposed, aiming at respectively teaching practice and future study.

碩士
國立臺灣科技大學
機械工程系
101
This study proposes a numerical model to predict the interlacing frequency of spin drawn yarn processed by a airjet nozzle, where the flow characteristics inside the nozzle is correlated with the experimental measurements via of a least square method. Three types of SDY nozzles, each with three different inlet diameters, are investigated in this study. Two processing conditions are studied in this research. The first processing condition is using yarn of 50D/24F with overfeed 1.5% at yarn speed 4460 m/min, and the second processing condition is using yarn of 50D/48F with overfeed 2.3% at yarn speed 4460 m/min. In the first processing condition, the airjet nozzle A delivers the highest interlacing frequency, while the airjet nozzle C gives the best performance in the second processing condition. The airjet nozzle C has the worst efficiency among three investigated nozzles despite of the processing conditions. The proposed numerical model is proven to deliver good prediction accuracy less than 0.3% error when compared with the available experimental measurements.

碩士
國立臺灣師範大學
設計研究所
96
This research applies the “poetic thought” process to the play writing and the visual expressions in experimental animation. Intermedia intertextuality was often seen between the text of poetry and the text of images. The nature of animation is closely related to poetry. For example, the poetic animation has—strong subjectivity from the author’s personal style, image which has its unique imagery, image symbols in Symbolism, and the surrealistic techniques. All of these are the same with the characteristic of poetry. The relationships among poetry, the poetic sentiment, and the animation are as follow: "Poetry," the dominant component of the script, expresses the subjective thinking of the animation creator; "the image (frame content)" is the work of the animation creator; "the poetic sentiment" is the visual feeling and the aesthetic psychology of the audience.Since animation is a big combination of different artistic domains, and there is high degree of freedom in how to apply techniques and materials, any idea could be put into practice. Therefore, we should emphasize the creativity and the aesthetic value in the content of animation. Poetry is related to thinking in nature, and is the power source for creators to express their thoughts and to create. While referring to the intertextuality phenomenon between animation and poetry, we should ground in the essence of poetic language. Therefore, the author applied "the Associative Tree", which was proposed by the poet Bai-Ling, as the "poetic thinking" method during the process of play writing and creative performance. Through the special characteristics of the poetic language, the author transformed the abstract human mood into concrete image and then the script of the poem. Moreover, the author used both realistic and abstract visual element in the animation, and united the highly painterly hand-drawn animation with personal sensitive style to visualize the poetic script, making every effort to unfold experimental animation in the artistic way.