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91	Simulation of the Filling of Epoxy in Resin Impregnated Paper Bushings : Analysis of Temperature Measurements during Filling of Epoxy and the Generation of New Filling Recipes to Avoid Cavities in the RIP Bushing Damsgaard Falck, Hanna January 2023 (has links) The goal of the project was to create a model in COMSOL Multiphysics that can simulate thefilling of resin (epoxy) in Resin Impregnated Paper (RIP) bushings. Using the model new fillingrecipes that avoid problematic double-fronts and thereby avoid the creation of cavities in thebushings should be designed. Another goal was to use Thermocouples and Fiber optics tomeasure the temperature at different positions during the filling to get a better understanding ofthe filling. The first step was to design and determine functions, parameters (such as thepermeability), boundary conditions etc. for the simulation model in COMSOL Multiphysics and tocalibrate the model to align with measurements of fillings previously done. The second part wasto increase the filling time to minimize the maximum difference between filling fronts in thebushings and thereby decrease the risk of problematical double-fronts that create cavities,which decrease the bushing's dielectrical properties. The simulation model aligned somewhatwith the measured data but there is a lot of uncertainty both in the measurements and due toassumptions made in the simulation model. The measurements from Thermocouples and Fiberoptics where almost identical and they indicated that the filling of the bushing is symmetric. Porous media COMSOL Multiphysicis Darcy's Law Richard's Equation Resin Impregnated Paper Bushings RIP Bushings Bushings Transformers Epoxy Simulation Other Materials Engineering Annan materialteknik Other Computer and Information Science Annan data- och informationsvetenskap
92	Etude du comportement mécanique à l’arrachement de fils multi-filamentaires enrobés dans une matrice cimentaire et influence de l’imprégnation / Study of the mechanical pull-out behaviour of multi-filament yarns embedded in a cementitious matrix and influence of the impregnation Aljewifi, Hana 12 December 2011 (has links) Cette recherche porte sur les fils multifilamentaires de verre utilisés pour renforcer les matériaux à base de ciment. Elle est focalisée sur les interactions mécaniques de ce type de fils, constitués d'un assemblage de milliers de filaments micrométriques, avec un micro-béton et sur le rôle spécifique de l'imprégnation du fil par cette matrice cimentaire. Trois pré-conditionnements des fils ont été employés lors de la fabrication des éprouvettes afin de moduler les conditions d'imprégnation par la matrice cimentaire. L'imprégnation de 5 fils multi-filamentaires par la matrice cimentaire a été caractérisée et les paramètres d'imprégnation ont été définis en s'appuyant sur des observations MEB, ainsi que des essais de porosimétrie au mercure et des essais spécifiques d'écoulement le long du fil enrobé. Des essais classiques d'arrachement de type pull-out ont été utilisés pour la caractérisation mécanique. L'analyse des liens entre les propriétés mécaniques et les paramètres d'imprégnation ont permis de mieux comprendre les micro-mécanismes d'interaction filaments / matrice cimentaire et d'expliquer le comportement macroscopique à l'arrachement. / This research deals with multi-filaments glass yarns used as reinforcement of cement based materials. It focuses on the mechanical interactions of these yarns, made of thousands of micrometric filaments, with a micro-concrete and on the specific part of the impregnation of the yarn by the cementitious matrix. Modulated impregnation conditions of the yarns were obtained by using three different manufacturing processes for the samples preparation. The impregnation of 5 multi-filament yarns by the cementitious matrix has been characterized and physical parameters of impregnation were determined using SEM investigations, mercury intrusion porosity measurements and specific tests of flow all along the embedded yarn. Classical pull-out tests have been used for the mechanical characterisation. The study of the links between the mechanical properties and the physical parameters of impregnation allowed accessing a better understanding of the filaments / cementitious matrix interaction micro-mechanisms, and explaining the macroscopic pull-out behaviour. Micro béton Interface fil /matrice Observations microstructurale par MEB Essai d'arrachement Micro concrete Glass multi-filament yarn and hemp fiber Intrerface yarn/matrix Microstructural observations by SEM Pull-out test
93	MY EYES DUE SEE Barfield, Johannes J 01 January 2018 (has links) My Eyes Due See is a multidimensional examination of the “black experience” in America. The installation is composed of a single-channel video, a music composition that utilizes music samples and live instrumentation, and sculptures made up of car parts and broomsedge grass. Each of these elements arranged in space share a nuanced and complicated view of blackness through the lens of a black man decoding personal history and American history simultaneously. Autonomy is the overarching theme throughout the work as it pertains to race, identity, urban and rural environments, and the relationship between generational trauma and nostalgia. Johannes James Barfield Johannes Johannes Barfield Barfield my eyes due see black video artist black artist road street asphalt fluorescent lights fluorescent forensic rod forensic trajectory rod rods automotive car parts road marking tape broomsedge ballistic trajectory rods grass objective reasonableness amplification nullification southern pine asphalt impregnated board Audio Arts and Acoustics Composition Fine Arts Interdisciplinary Arts and Media Other Film and Media Studies Sculpture
94	Formwork-free, continuous production of variable frame elements for modular shell structures Ivaniuk, Egor, Mechtcherine, Viktor 10 November 2022 (has links) Conventional construction of concrete shells involves a costly and time-consuming erection of custom formwork. An alternative approach that avoids this is an on-site assembly of shells from prefabricated modules. This article presents a new, highly automated method for the production of such modules. The proposed method combines the technology of full-width 3D concrete printing using strain-hardening cement-based composite and the technology of robotic textile mesh production from mineral-impregnated carbon yarns. info:eu-repo/classification/ddc/690 ddc:690

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