Press felts are highly critical components of the paper machine. A degraded press felt could lead to paper web breaks, which requires the paper machine to be restarted. Moreover, a degraded felt influences the quality of the paper, leading to paper disposal. Condition monitoring aims at minimising the risk of paper web breaks, unsatisfactory paper quality and other types of production loss while maximising the useful life of the press felts. However, installing a new condition monitoring system is expensive and the installation can be difficult to fit into the scheduled maintenance stops. This thesis investigates the possibility of using existing monitoring systems instead of installing a new one. Four possible approaches of monitoring the degradation of the press felts have been explored. The identified approaches of press felt monitoring were tested by using data acquired through existing monitoring systems of the paper machine PM2 at BillerudKo-rsnäs in Karlsborg, located in the north of Sweden. The first approach is based upon process parameters. This approach could, however, not be properly investigated due to a malfunctioning sensor. The second approach revolves around the natural frequencies of the felt and the frequency changes as the felt degrades. The remaining two approaches originates from the hypothesis that felt degradation could lead to impacts as the possibly uneven felt passes the rollers. One approach is to detect these possible impacts by using the time domain feature kurtosis. The other approach is to monitor the harmonics these impacts could lead to. Neither the natural frequency nor the kurtosis approach was deemed promising, partly based on the results of the analysed data but also due to intrinsic deficiencies of these approaches. The approach based on felt harmonics did, however, exhibit indications that it might be a feasible monitoring technique. The felt harmonics approach should be further investigated. Furthermore, a python program that can synchronise data from different sources was developed. This program enables degradation features to be extracted using machine learning algorithms. However, due to the lack of vibration data and labels of the current felt condition, machine learning was not applied. / Pressfiltar är ytterst kritiska komponenter i pappersmaskinen. En nedsliten pressfilt kan orsaka pappersbanbrott vilket innebär att pappersmaskinen måste startas om. En nedsliten filt kan också påverka papperskvaliteten vilket resulterar i att papper måste kasseras. Tillståndsövervakning är ett steg närmare att kunna optimera användandet av pressfiltarna, det vill säga maximera livstiden samtidigt som risken för oplanerade stopp minimeras. Att installera ett nytt tillståndsövervakningssystem kan dock vara dyrt och installationen kan vara svår att rymmas i de planerade underhållsstoppen. Detta masterarbete utreder möjligheten att använda existerande övervakningssytem istället för att installera ett nytt. Fyra möjliga angreppssätt för tillståndsövervakning av pressfilten utforskades. De identifierade övervakningsteknikerna testades genom att använda data från existerande övervakningssystem på pappersmaskinen PM2 hos BillerudKorsnäs i Karlsborg utanför Kalix. Det första angreppssättet baseras på processparametrar. Detta angreppssätt kunde dock ej utvärderas på grund av en defekt sensor. Det andra angreppssättet kretsar kring filtens egenfrekvenser och dessas förändring när filten slits ut. Återstående två angreppssätt har sitt ursprung i hypotesen att en försämrad filt kan ge upphov till slag när den eventuellt ojämna filten passerar valsarna. Ett angreppssätt är att detektera dessa eventuella vibrationer genom tidsdomänfunktionen kurtosis. Det andra angreppssättet som använts är att övervaka de övertoner som slagen kan leda till. Varken angreppssättet baserat på egenfrekvens eller det baserat på kurtosis bedömdes lovande. Detta delvis baserat på resultaten från analyserad data men också på grund av de inneboende bristerna för dessa två angreppssätt. Det angreppssätt som baseras på filtens övertoner visade däremot indikationer på att det kan utgöra en möjlig övervakningsteknik och detta angreppssätt bör därför utforskas vidare. Vidare utvecklades ett pythonprogram som kan synkronisera data från olika källor. Programmet möjliggör applicering av maskininlärningsalgoritmer. På grund av brist på vibrationsdata och klassificering av nuvarande filttillstånd applicerades dock inte maskininlärning. / NonStopp

No description available.

No description available.

Wechselnde Richtungen von Flächen in unterschiedlichen „Amplituden“ ... – Das Leporello kann in seinen unterschiedlichen Ausdehnungen in verschiedener Weise gesehen, gelesen werden: nach außen, über die Faltungen oben und unten sich öffnend – oder – von außen über die obere und unterer Ebene einander zusammenführend.

The purpose of the thesis was to create a data glove that can translate ASL by reading the finger- and hand movements. Furthermore, the applicability of conductive fabric as stretch sensors was explored. To read the hand gestures stretch sensors constructed from conductive fabric were attached to each finger of the glove to distinguish how much they were bent. The hand movements were registered using a 3-axis accelerometer which was mounted on the glove. The sensor values were read by an Arduino Nano 33 IoT mounted to the wrist of the glove which processed the readings and translated them into the corresponding sign. The microcontroller would then wirelessly transmit the result to another device through Bluetooth Low Energy. The glove was able to correctly translate all the signs of the ASL alphabet with an average accuracy of 93%. It was found that signs with small differences in hand gestures such as S and T were harder to distinguish between which would result in an accuracy of 70% for these specific signs. / Syftet med uppsatsen var att skapa en datahandske som kan översätta ASL genom att läsa av finger- och handrörelser. Vidare undersöktes om ledande tyg kan användas som sträcksensorer. För att läsa av handgesterna fästes ledande tyg på varje finger på handsken för att urskilja hur mycket de böjdes. Handrörelserna registrerades med en 3-axlig accelerometer som var monterad på handsken. Sensorvärdena lästes av en Arduino Nano 33 IoT monterad på handleden som översatte till de motsvarande tecknen. Mikrokontrollern överförde sedan resultatet trådlöst till en annan enhet via Bluetooth Low Energy. Handsken kunde korrekt översätta alla tecken på ASL-alfabetet med en genomsnittlig exakthet på 93%. Det visade sig att tecken med små skillnader i handgester som S och T var svårare att skilja mellan vilket resulterade i en noggrannhet på 70% för dessa specifika tecken.

Understanding the interactions of polymer interfaces is essential to improve polymer-based designs, as the properties of the interface are often different than those of the bulk material. This thesis explores the interfacial interactions of polymer interfaces for two classes of materials, additive manufacturing materials and fiber-reinforced composites. Additive manufacturing (AM) refers to a number of processes which rely on data generated from computer-aided design (CAD) programs to construct components by adding material in a layer-by-layer fashion. AM continues to generate a substantial amount of interest to produce fully functional products while reducing tooling costs associated with traditional manufacturing techniques such as casting and welding. Recent advancements in the field have led to the production of multi-material printing that has the potential to create products with enhanced mechanical properties and additional functionality. This thesis attempts to characterize the fracture resistance of AM materials produced by the PolyJet process. Test standards established for mode I fracture testing of adhesive joints are adapted to evaluate the fracture resistance and interface between two printed acrylic-based photopolymers. Significant differences in fracture energy and loci of failure between the selected test configurations were observed depending on the print orientation. Failures were nominally seen to occur at the interface, alternating from one adherend interface to another in a random fashion. Results demonstrated a decreasing trend in fracture energy at slower crack propagation rates, indicating that such dependency is associated with the fracture resistance of the interface. T-peel tests conducted on specimens prepared with both constant and graded interlayers revealed enhanced peel resistance with gradient interlayers, suggesting design opportunities of enhanced fracture toughness by implementing intricate material patterns at the interface of the two photopolymers. Fiber reinforced composite (FRCs) materials have become increasingly desirable in a number of industrial applications where weight reduction is critical for increased payloads and higher performance. When manufacturing structures from these materials, the presence of friction in the composite forming process is seen to have a major effect on the finished quality. Friction between the plies, or between the composite laminate and forming tool, can be undesirable as shape distortions such as wrinkles can appear and compromise the structural integrity of the finished product. To evaluate these frictional processes, a standard rheometer is used to evaluate tool-ply friction on dry textile fabrics and graphite/epoxy prepregs over a range of temperatures, pressures, and sliding velocities. The results provide some general insights into the frictional response of composite prepregs as a function of the manufacturing environment. The materials tested are shown to have different mechanisms that govern the frictional processes. In particular, the results of friction testing on the prepreg indicate that friction comes from a contribution of both Coulomb and viscous-related mechanisms, the latter which become especially at higher temperatures. / Master of Science

This investigation explored the feasibility of recently developed toughened cyanate ester networks as candidate materials for high performance composite matrix applications. The resin investigated was a Bisphenol-A cyanate ester toughened with hydroxy functionalized phenolphthalein based amorphous poly(arylene ether sulfone). The thermoplastic modified toughened networks exhibited improvement in the fracture toughness over the base cyanate ester networks without significant reductions in mechanical properties or glass transition temperature. Void free, unidirectional carbon fiber prepreg was successfully manufactured with the toughened cyanate resin using a solventless hot-melt technique. The resin mass fraction of the prepregs was between 31 and 35%. The carbon fiber, toughened cyanate ester prepreg was fabricated into composite panels for mechanical and physical testing. The cure cycle used to manufacture the composite laminates was developed with the aid of a process simulation model developed by Loos and Springer. In order to accurately simulate the resin curing and flow processes, the cure reaction kinetics and melt viscosity was characterized as a function of temperature and degree of cure and input into the simulation model. The model generated cure cycle was used in the manufacture 8-ply unidirectional and 16-ply quasi-isotropic composite laminates. The manufactured laminates were well consolidated to the specified fiber volume fraction between 59 and 60%. Photomicrographs showed that the laminates are void free, the fiber and resin distribution is uniform and fiber wet-out is very good. Mechanical tests were performed to measure the impact damage resistance and shear properties of the toughened cyanate ester resin composites. The results show improvements in impact damage resistance compared with the commonly used hot-melt epoxy resin composites. The influence of processing on performance was observed from the results of shear tests. Carbon fabric composite panels were manufactured by liquid molding processes (resin transfer molding and resin film infusion), with a series of four toughened cyanate ester resins generated by varying the concentration and the molecular weight of the toughener. The panels were subjected to physical, damage tolerance, and fracture toughness tests. The results of physical testing indicate consistently uniform quality, and the void content was found to be less than 2%. The toughened cyanate ester composites exhibited significantly improved impact damage resistance and tolerance compared with hot-melt epoxy systems. Marked increase in the mode II fracture toughness were observed with an increase in the concentration and the molecular weight of the toughener. / Ph. D.

Cette thèse de doctorat constitue une première étude de synthèse de la céramique de cuisine (Brittle Ware), de l’époque romaine à l’époque omeyyade en Syrie. Cette recherche repose sur une approche méthodologique combinant un classement typologique des formes et un classement par groupes de pâtes. Le corpus étudié provient de plusieurs sites archéologiques de Syrie du nord, dont la céramique de cuisine est encore inédite et pour laquelle on ignore les centres de production (Apamée, Andarin, Alep et Dibsi Faraj). Ce travail a entrepris d’identifier le nombre d’ateliers et leur localisation, leur profil de production et leur aire de diffusion. Les objectifs sont de caractériser la production de Brittle Ware depuis la manufacture jusqu’aux contextes de consommation, L’étude chrono-typologique a permis de définir le répertoire de la Brittle Ware et de situer sa production entre l’époque hellénistique (3e av. J.-C.) et l’époque mamelouke (13e s. apr. J.-C.). Aux époques romaine, byzantine et omeyyade, un même assemblage formel, constituant un service de cuisine se diffuse dans toute la province antique de Syrie. Ce service de cuisine est constitué d’un pot à cuire haut et fermé qui devait servir aux liquides et aux bouillies, d’une casserole ouverte pour les plats mijotés et d’une cruche. L’analyse minéralogique et chimique des pâtes a identifié cinq groupes de pâte, correspondant à cinq zones de production. L’origine des matières premières exploitées a pu être localisée dans le nord-ouest de la Syrie, à proximité de l’Euphrate et dans le sud-ouest de la Syrie. L’étude des pâtes et des formes de Brittle Ware dans leur contexte géographique et chronologique a de surcroît montré que ces cinq sources d’argile correspondent à cinq centres de production. Les profils de ces centres de production ont pu être définis : leur durée d’activité et l’aire géographique de leur diffusion varie pour chacun d’entre eux. Quatre sont des ateliers syriens alors que le dernier semble être localisé plus au sud. Deux centres de production ont une diffusion supra-régionale (couvrant plusieurs zones géographiques). L’un diffuse ses produits de Syrie occidentale jusqu’à l’Euphrate et l’autre, moins attesté à l’est, constitue l’unique fournisseur de la ville d’Apamée. Les trois autres centres ont une distribution régionale. La plupart de ces ateliers partagent le même service de cuisine, témoignant de la transmission d’un savoir-faire technique et formel sur plusieurs générations. Alors qu’à l’époque hellénistique, on note sur quelques sites la présence d’une vaisselle culinaire différente, qui s’apparente aux traditions de l’Âge du Fer et de l’Âge du Bronze syrien, l’étude de la distribution de la Brittle Ware en Syrie révèle que celle-ci représente l’unique céramique de cuisine utilisée aux époques romaines et byzantines. En outre, les formes typiques de la Brittle Ware ne sont pas attestées en dehors des limites de la province antique de Syrie : en Cilicie, en Palestine ou à Chypre. Les céramiques culinaires des régions limitrophes de la Syrie constituent d’autres faciès régionaux qui partagent néanmoins des traditions formelles et techniques avec les productions de Brittle Ware. Ces autres faciès sont caractérisés par leurs répertoires typologiques spécifiques, par ailleurs inconnus en Syrie. Les cartes de distribution de la Brittle Ware et la comparaison avec les productions des régions limitrophes montrent par conséquent que la production de Brittle Ware représente un commerce à échelle supra-régionale, tourné essentiellement vers l’intérieur de la Syrie. Le fait que ce commerce ne dépasse pas les limites de la province, loin d’être un facteur négatif, indique que la production de Brittle Ware est suffisamment prospère pour défier la concurrence. L’étude des contextes de production de la Brittle Ware montre que cette catégorie de vaisselle, bien qu’utilitaire était l’objet d’une production de masse, diffusée à l’échelle d’une province et provenant sans doute de grands centres de production spécialisés. Cette recherche couvrant trois périodes historiques contribue à notre connaissance de l’économie syrienne, car elle illustre la pérennité des centres de production et de certains réseaux d’échange, depuis l’époque romaine jusqu’à la fin de l’époque omeyyade.

Depuis quelques années, l’urbanisme tend à considérer de plus en plus la question patrimoniale. Au Québec, c’est suite à l’adoption, en 1980, de la Loi sur l’aménagement et l’urbanisme que fut formellement introduite la donne patrimoniale dans la pratique urbanistique. Bien que cette pratique tente aujourd’hui de poser la conservation du patrimoine bâti comme l’une de ses préoccupations, elle ne parvient pas à l’assumer complètement. En nous basant sur la définition du patrimoine urbain telle que proposée par Gustavo Giovannoni, nous voulons, par cette étude, amorcer une réflexion sur les enjeux d’une approche urbanistique du patrimoine urbain. Nous proposons dans un premier temps un survol de l’évolution de la notion de patrimoine urbain. Cette évolution est mise en relation avec la constitution d’un regard sur le patrimoine bâti québécois. Nous analysons, par la suite, trois moments clés dans la constitution d’un tel regard. La mise en contexte de la naissance de l’urbanisme québécois constitue, quant à elle, le troisième et avant-dernier volet de notre réflexion. À la lumière de cette analyse, nous considérons que le regard de l’urbaniste, posé sur le patrimoine bâti, témoigne encore aujourd’hui d’un désintérêt pour la forme. L’abandon du domaine du physico-spatial au profit d’une gestion rationnelle de la ville a engendré une méconnaissance des processus de constitution des ensembles bâtis et du rôle des formes spécialisées polarisantes. Une véritable approche urbanistique du patrimoine bâti ne saurait passer que par la reconnaissance des processus morphogénétiques des ensembles urbains anciens et de leur inscription dans la ville contemporaine. / For a few decades now, urban planners have tried to include the conservation of built environment in their practices. In Quebec, the first introduction of this consideration takes place in 1980 by the adoption of the Act respecting land use planning and development. Unfortunately, this new consideration was never fully included in the practice, even if urban planning tried to considerer conservation of built environment as one of his main interest. Regarding the definition of built heritage by Gustavo Giovannoni, this study is concerned with the consideration of built heritage in an urban planning’s point of view. In the first part, we will go through an overview of the evolution of the term built heritage. Secondly, we will review three different moments in the constitution of a specific point of view of Quebec’s built heritage. Finally, we will dedicate the third part of our thesis to the birth of urban planning in the province of Quebec. The results of our study show that the modern urban planner’s point of view on built heritage is still characterized by a disinterest in the urban and architectural forms. The focus made by urban planners on the rational management of the twentieth century’s city caused a misunderstanding of its evolution process. What we will demonstrate is that a real urban planning’s point of view on built heritage must consider these processes as well as the inclusion of the old city within the new agglomeration.

Driven by the crippling command of Eros, my work provides a veiled exposure to my secret life in love, desire, fear, and obsession. My sculptures are the physical evidence of an emotional realm coming forth in a coded language that is, even to me, only remotely accessible. The Demon that Lives in My Bedroom, the saga of the Cat People, the stories of Trasnichi and the Love Crusade; all came to me in a beam of thought. Once the beam takes hold, it becomes my obsession, and the era of that work begins. I can trace my development through these eras of obsessions.