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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.
1

The effect of board coating and precalendering on coating coverage and surface structure /

Kuni, Stefan. January 2003 (has links)
Dissertation--Åbo Akademi university, 2003. / Notes bibliogr.
2

Analyse expérimentale et modélisation du comportement non linéaire thermomécanique de cloison en plaques carton-plâtre-carton, vissées et soumise à des charges thermiques et mécaniques / Experimental analysis and modeling of nonlinear thermomechanical behavior for partition wall with plates cardboard-plasterboard-cardboard, screwed and subjected to thermal and mechanical charge

Do, Thanh Trung 08 December 2011 (has links)
Dans le cadre de ce travail nous étudions le comportement thermomécanique d'une cloison légère faite de plaques carton-plâtre-carton (CPC) vissées sur une ossature métallique. Cette étude consiste d'une part à mener une analyse expérimentale pour identifier les propriétés thermiques, mécaniques et thermomécaniques des différents constituants de la cloison, et d'autre part, à développer un modèle analytique et un modèle numérique robuste du comportement thermomécanique non linéaire de cloisons légères soumises à un incendie naturel. Pour une modélisation robuste, nous avons d'une part développé un modèle du comportement thermomécanique de l'assemblage par vissage, et d'autre part développé un modèle global de la cloison légère en combinant, le modèle thermomécanique non linéaire du vissage, le modèle du comportement thermomécanique d'une plaque CPC et le modèle de l'ossature métallique. Comme il existe une grande variabilité dans les résultats expérimentaux, les incertitudes doivent être prises en compte. Pour ce faire, nous avons proposé d'utiliser un modèle probabiliste du comportement de l'assemblage par vissages / In this research, we study the thermomechanical behavior of a light partition wall made of carton-gypsum-carton (CGC) plates screwed to a metallic frame. This study consist firstly, to conduct an experimental analysis in order to identify the thermal, mechanical and thermomechanical propeties of the differents components of the light partition wall, and secondly, to develop an analytical model and a robust numerical model of nonlinear thermomechanical behavior of the partition walls subjected to natural fire. For a robust model, firstly, we developped a model of the thermomechanical behavior of the assembly by screws, and then developped a global model of the light partition wall by combining the nonlinear thermomechanical model of the assembly by screws, the model of the thermomechanical behavior of a CGC plate and model of the metal frame. As there is important variability in experimental results, the uncertainties must be taken into account. To do this, we proposed to use a probabilistic model of the behavior of the assembly by screw
3

Mechanical Behaviour of Adhesive Joints in Cartonboard for Packaging

Korin, Christer January 2009 (has links)
A cartonboard package is often sealed and closed with an adhesive – either a hot-melt adhesive (adhesives that are applied in a molten state on the cartonboard) or a dispersion adhesive (adhesives that are applied as water-based dispersions). This thesis focuses on the process of hot-melt gluing, and how material properties and process conditions affect the performance of the adhesive joint. Requirements vary depending on how the package is to be used. A package that is only supposed to protect the product during transport differs from one that is supposed to attract consumers and facilitate their use of the product. If a package has been opened, due to external or internal forces that cause a fracture in the adhesive joint, the consumer may choose another package instead. A fracture of the adhesive joint may occur in several different ways; for example, a cohesive fracture in the adhesive, an interfacial fracture between the adhesive and one of the cartonboard surfaces, and a cohesive fracture in the cartonboard. The traditional way of testing the adhesive joint is to subjectively evaluate the fibre tear after manually tearing the joint apart. The primary interest of this study has been to find an objective method that can characterise the adhesive joint – that is, its strength and joint characteristics. The work has principally concentrated on physical experiments where the Y-peel method has been evaluated and further developed, including the construction of a laboratory adhesive applicator. Adhesive joint failure is analysed and correlated to the force-elongation curve during Y-peel testing in order to explore various mechanisms of the failure. The force versus elongation curves are transformed into a force versus inelastic deformation curve for the adhesive joint. The inelastic deformation of the adhesive joint is defined as the inelastic opening of the adhesive joint perpendicular to the cartonboard surface. The dissipative descending energy has been used to characterise the adhesive joint. High descending dissipative energy showed high resistance against final failure of the joint. This correlates very well with the manual fibre-tear test. Characteristic force-elongation curves in Y-peel testing – that is, the shape of the curve – have been analysed, and four main failure modes have been identified. The finite element method has been used to predict mechanical behaviour in the ascending part of the force-elongation curve. When it comes to local behaviour, a high stiffness adhesive results in bending behaviour while a low results in shearing, but on a global scale, no big difference was detected on the ascending part of the force-elongation curve. The new laboratory adhesive applicator and finite element method can be used to objectively design the interaction between the adhesive and the cartonboard for a specific application. This can be achieved by modifying the cartonboard, the adhesive or the process parameters.
4

An essay on the one-act play with special reference to the theatre of Dancourt

Anderson, Robert Edward, January 1973 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
5

Zařízení na vkládání oplatků do kartónových krabic / Machine for putting waffles in cartons

Kobza, Milan January 2008 (has links)
The subject of this thesis is the design of construction the machine for putting waffles in cartons. This device is manually adjustable for 3 kind of waffles and cartons and isn’t part of any technological line. This thesis contains introductory study, concept of possible variations, control of important parts of machine and prices of these parts.
6

Procesní FMECA analýza kartonového stojanu / FMECA procedural analysis of a cardboard stand

Potěšilová, Hana January 2015 (has links)
The thesis deals with application of method FMECA to the manufacturing process of cardboard stand. The aim of work is to describe cardboard stand manufacturing, identify fault conditions and their consequences in particular manufacturing processes. In order to increase reliability of cardboard stands, we have designed measures based on analysis of criticality.
7

Analyse expérimentale et modélisation du comportement non linéaire thermomécanique de cloison en plaques carton-plâtre-carton, vissées et soumise à des charges thermiques et mécaniques

Do, Thanh Trung 08 December 2011 (has links) (PDF)
Dans le cadre de ce travail nous étudions le comportement thermomécanique d'une cloison légère faite de plaques carton-plâtre-carton (CPC) vissées sur une ossature métallique. Cette étude consiste d'une part à mener une analyse expérimentale pour identifier les propriétés thermiques, mécaniques et thermomécaniques des différents constituants de la cloison, et d'autre part, à développer un modèle analytique et un modèle numérique robuste du comportement thermomécanique non linéaire de cloisons légères soumises à un incendie naturel. Pour une modélisation robuste, nous avons d'une part développé un modèle du comportement thermomécanique de l'assemblage par vissage, et d'autre part développé un modèle global de la cloison légère en combinant, le modèle thermomécanique non linéaire du vissage, le modèle du comportement thermomécanique d'une plaque CPC et le modèle de l'ossature métallique. Comme il existe une grande variabilité dans les résultats expérimentaux, les incertitudes doivent être prises en compte. Pour ce faire, nous avons proposé d'utiliser un modèle probabiliste du comportement de l'assemblage par vissages
8

Entwicklung eines Analysealgorithmus zur Erfassung der Materialverteilung tiefgezogener Kartonformteile mittels konfokaler Abstandssensoren / Development of an algorithm to analyse the material distribution of deep-drawing carton shells with a confocal measurement device

Witt, Tilman 30 March 2017 (has links) (PDF)
Die vorliegende Arbeit hat die Entwicklung und Validierung eines Analysealgorithmus zur objektiven Auswertung der Materialverteilung entlang der Zarge an gezogenen Karton-formziehteilen zum Ziel. Die dafür verwendeten Messdaten werden durch Oberflächenab-tastung mit konfokaler Sensorik erzeugt. Unter Anwendung des Analysealgorithmus wer-den die Einflüsse der Prozessparameter auf die Materialverteilung ermittelt. Abschließend wird aus den gewonnenen Daten ein Ansatz zur Berechnung der Werkzeuggeometrie ent-wickelt. Zur Bestimmung der Materialverteilung wird die Zarge beidseitig abgetastet. Aus der Diffe-renz der Radien von Außen- und Innenkontur wird der Dickenverlauf entlang der Zarge bestimmt, die die Materialverteilung beschreibt. Die Messung mit konfokalen Sensoren wird mit mikroskopischen Aufnahmen von Mikrotomschnitten und röntgentomographi-schen Aufnahmen geprüft. Der Mittelwert und die Standardabweichung des Dickenverlaufs charakterisieren die Mate-rialverteilung. Der Analysealgorithmus ermittelt aus den durch Sensoren aufgenommenen Daten die charakteristischen Werte. In der Auswertung zeigt sich, dass eine Höhere Zieh-stempeltemperatur als Ziehbüchsentemperatur sowie eine hohe Temperatursumme die mittlere Dicke verringern. Eine hohe Faltenhalterkraft und eine hohe Stempeltemperatur bewirken eine gleichmäßigere Materialverteilung. Der ermittelte Zusammenhang von der Beeinflussung des Mittelwertes der Dicke mit den Temperaturunterschieden von Stempel und Büchse wird durch ein Modell der thermischen Ausdehnung von Stempel und Büchse belegt. / The present thesis comprises the development and validation of an algorithm for the objec-tive evaluation of data on material distribution alongside the architrave of drawn cardboard shells. The necessary data are obtained through detection of the surface with confocal sensors. The influences of the process parameters on material distribution are investigated with algorithm. Resulting from this data, the basis for the calculation of the tools geometry is developed. The determination of material distribution is accomplished by double-sided optical scanning of the architraves inner and outer surface. The trend of cardboard thickness alongside the architrave is calculated by the subtracion of the inside radius from the outside radius of the cardboard shell. The cardboard thickness describes material distribution. The measures with confocal sensors are approved of examined microtome cuts under microscope and x-ray analyses. Material distribution is characterised by average of the thickness and standard deviation of thickness. The analysis algorithm calculates with sensor data the characteristic values. A higher temprature of the drawing die as the temprature of the drawing box and the sum of temperatures lead to a decrease of the average thickness. The combination of a high die temperature and a high force applied by the blankholder result in a more even material distribution. The identified correlation of average thickness and temperature gradients between the drawing die and the box is discribed by thermal expansion of die and box.
9

Entwicklung eines Analysealgorithmus zur Erfassung der Materialverteilung tiefgezogener Kartonformteile mittels konfokaler Abstandssensoren

Witt, Tilman 30 March 2017 (has links)
Die vorliegende Arbeit hat die Entwicklung und Validierung eines Analysealgorithmus zur objektiven Auswertung der Materialverteilung entlang der Zarge an gezogenen Karton-formziehteilen zum Ziel. Die dafür verwendeten Messdaten werden durch Oberflächenab-tastung mit konfokaler Sensorik erzeugt. Unter Anwendung des Analysealgorithmus wer-den die Einflüsse der Prozessparameter auf die Materialverteilung ermittelt. Abschließend wird aus den gewonnenen Daten ein Ansatz zur Berechnung der Werkzeuggeometrie ent-wickelt. Zur Bestimmung der Materialverteilung wird die Zarge beidseitig abgetastet. Aus der Diffe-renz der Radien von Außen- und Innenkontur wird der Dickenverlauf entlang der Zarge bestimmt, die die Materialverteilung beschreibt. Die Messung mit konfokalen Sensoren wird mit mikroskopischen Aufnahmen von Mikrotomschnitten und röntgentomographi-schen Aufnahmen geprüft. Der Mittelwert und die Standardabweichung des Dickenverlaufs charakterisieren die Mate-rialverteilung. Der Analysealgorithmus ermittelt aus den durch Sensoren aufgenommenen Daten die charakteristischen Werte. In der Auswertung zeigt sich, dass eine Höhere Zieh-stempeltemperatur als Ziehbüchsentemperatur sowie eine hohe Temperatursumme die mittlere Dicke verringern. Eine hohe Faltenhalterkraft und eine hohe Stempeltemperatur bewirken eine gleichmäßigere Materialverteilung. Der ermittelte Zusammenhang von der Beeinflussung des Mittelwertes der Dicke mit den Temperaturunterschieden von Stempel und Büchse wird durch ein Modell der thermischen Ausdehnung von Stempel und Büchse belegt. / The present thesis comprises the development and validation of an algorithm for the objec-tive evaluation of data on material distribution alongside the architrave of drawn cardboard shells. The necessary data are obtained through detection of the surface with confocal sensors. The influences of the process parameters on material distribution are investigated with algorithm. Resulting from this data, the basis for the calculation of the tools geometry is developed. The determination of material distribution is accomplished by double-sided optical scanning of the architraves inner and outer surface. The trend of cardboard thickness alongside the architrave is calculated by the subtracion of the inside radius from the outside radius of the cardboard shell. The cardboard thickness describes material distribution. The measures with confocal sensors are approved of examined microtome cuts under microscope and x-ray analyses. Material distribution is characterised by average of the thickness and standard deviation of thickness. The analysis algorithm calculates with sensor data the characteristic values. A higher temprature of the drawing die as the temprature of the drawing box and the sum of temperatures lead to a decrease of the average thickness. The combination of a high die temperature and a high force applied by the blankholder result in a more even material distribution. The identified correlation of average thickness and temperature gradients between the drawing die and the box is discribed by thermal expansion of die and box.
10

Aproveitamento de embalagens cartonadas em compósito de polietileno de baixa densidade. / Re-use of carton packages in low density polyethylene composites.

Borges, Daliana Gomes 05 September 2007 (has links)
A produção de materiais plásticos tem se elevado para 169 milhões de toneladas no mundo, no ano de 2003. Uma parte considerável destes polímeros sintéticos, 36% na Europa são destinados ao setor de embalagens. Estas matérias primas são utilizadas por um período de tempo bastante curto e geram um volume de descartes importante. Mesmo com um desenvolvimento considerável de linhas de gestão dos descartes, seu tratamento e sua eliminação colocam ainda problemas provenientes da dificuldade em reutilizar tais embalagens na forma em que são geradas, seja pelo estado de limpeza em que são descartadas, seja pela composição multi-material que é utilizada para sua produção. O presente trabalho busca o reaproveitamento de Embalagens Cartonadas pós-consumo como reforço em compósito com Polietileno de baixa densidade para i) maximizar o teor de ELV empregada no compósito e ii) melhorar o aspecto visual do compósito por meio de incorporação de concentrado de cores e corantes. Por meio do processo de extrusão, preparou-se o compósito na forma granulada. O material granulado foi moldado por injeção para obtenção dos corpos-de-prova para ensaios de tração. As propriedades viscosimétricas do compósito foram avaliadas por meio do Índice de Fluidez e a morfologia do compósito foi avaliada por meio de microscopia eletrônica de varredura e espectroscopia de energia dispersiva de raio X. Nas condições do trabalho pode-se afirmar que o teor de Embalagem Cartonada que apresenta o melhor conjunto de propriedades de tração está entre 20 e 25% (p/p) no compósito; a utilização de concentrado de cor para melhoria do aspecto visual do compósito não tem influência no conjunto de propriedades de tração do mesmo. / Plastics materials production has increased to 169 million tons in the world in 2003. A great part of these synthetic polymers, it means 36% in Europe are used in packaging applications. These raw materials are used for a short time and produces a great volume of residues. Even with a great development of residues management, its treatments and elimination causes several problems due to difficulty in reuse these packages as its were discarted or the state of dirtiness in which they are discarted or even by the composition multi-material of these packages. This work has as a goal the reuse of Carton Packages (CP) post-use as a reinforcement in a Low Density PolyEthylene (LDPE), to i) maximize the content of CP in the composite and ii) improve the composite visual aspect by means of color masterbatches. With aid of extrusion process, the granuleted composite was prepared. These granulated was moulded by injection to obtain test specimens for mechanical tests. Composites viscosimetric proprierties and morphology were evaluated by means of Melt Index and Scanning Electronic Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). In the work conditions it can be postulate that the best content of CP in the composite that gives the best mechanical properties is between 20 and 25% (w/w); the use of color masterbatches for improve the composite visual aspects has no influence over mechanical properties.

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