Thesis (MBA)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The South African table grape industry has a very fruitful history. The landscape of the South African table grape industry has changed at a rapid rate since deregulation in 1997. The sustainability of these changes was questioned and created the opportunity for this research. The orientation of this research report outlines the structure to this research. It indicates that the South African table grape industry is experiencing a strong trend of consolidation of the production and exporter base. Economically sustainable growers and marketing companies produce or attract more volumes of table grapes to export to global destinations. The environment provides the background to the South African table grape industry, since deregulation. Five major trends in this industry are important to mention and give perspective to the research question, namely: - The number of producers has declined at a rapid rate (about 52%) since deregulation. - Traditional production regions like the Berg and Hex River have become less important due to the timing of product supplied to the market. New geographic production regions have grown in importance, like the Orange River and Northern Province. - Production volumes of table grapes have slowed down over the last ten years and in certain regions have become stagnant. - The cultivar spectrum of table grapes has changed from seeded grape that is marginal to the market to a seedless product that earns premiums in the market. - There has been a shift in marketing of table grapes from Western countries like the UK and EU to Eastern countries. There are also certain factors that have a profound impact on the South African table grape industry, namely economic, environmental, political, social and global factors, which required further investigation. The evaluation of trends in the industry and the factors that affect the industry revealed the problem statement for this research and set the foundation for the research question. The research question of this study is: What are the distinguishable marketing models currently used by South African exporters and how sustainable is each model? The research methodology demonstrates that the South African table grapes industry is split into two dominant marketing models, which are the marketing agent and the grower-exporter model. A marketing model metrics was designed, based on literature and consultations with industry experts via a questionnaire, to evaluate the economic, social and environmental sustainability of these two marketing models. The method of data analysis was a qualitative investigation into the sustainability of marketing models that exist in the South African table grape industry. The structure of the holistic marketing dimension model which was used has the following four dimensions (Kotler & Keller, 2009:61): -Relationship marketing - Performance marketing - Integrated marketing - Internal marketing. Semi-structured interviews were held with six different marketing entities in the South African table grape industry, which represented 40 percent of the total population. The interviews were held by utilising a discussion guide that comprised of standard questions to all the interviewees. The information gathered from the interviews was used to design a conceptual marketing model, with the main objective of being sustainable on an economic, social and environmental level. This relevance and practicality of this conceptual marketing model was tested against a grower-exporter model in the South African table grape industry, called Angon Fruit. The findings of this research report focused on the triple bottom-line approach of building economic, social and environmental capital. The economic sustainability revealed the following factors to consider: - Grower-exporter model is a more sustainable marketing model, due to low cost operations. -Marketing agent model should have a definite competitive advantage, to justify relevance in the cost-chain. - Sustainable market share in volume of table grapes to export by a marketing company is five percent. - Prices paid to growers by a marketing company should keep track of inflation on inputs and a ten percent premium earned on top of the production cost is regarded as sustainable. - A sustainable commission percentage charged by marketing companies should not exceed five percent of free on board (FOB) value at Cape Town port. - Growers need to replace marginal seeded cultivars with premium seedless cultivars that are high in demand in global markets. - Marketing companies should supply table grapes at a split of 50 percent to Western countries and 50 percent to Eastern countries. - The sustainability of the Berg and Hex River production regions is at risk, due to global competitions from South American countries. The South African table grape industry revealed the following social sustainability findings: - A marketing company should have a social policy, which governs social responsibility projects (CSI). - The marketing company should be involved one major project instead of a few smaller projects. - Corporate social investment (CSI) projects should aim to provide the opportunity to improve education and training, improve health status and to develop sport among the youth. - The marketing company should not invest in CSI projects if the economic sustainability is at risk. The objective is to invest five percent of net profit in CSI projects, annually. Environmental sustainability revealed the following factors to consider: - A marketing company should have an environmental policy. - The company should measure its carbon and water footprint at least every two years, with the objective to reduce or optimise the level of use. - The company should embrace and implement green technology that utilises renewable energy to reduce the dependency on fossil fuels and coal-generated electricity. - The use of water should be optimised, through implementation of advanced technology. - The marketing company should adopt the practice of recycling. The conclusion to this research report is that the table grape industry is still economically sustainable, however more work can be done on the social and environmental sustainability. Finally, ten recommendations are made to the South African table grape industry to consider from a sustainability perspective. Companies can consider implementing these best practices into their marketing of table grapes.

<p>Industrial robots have been used for a long time in the industry. Despite this thedevelopment of advanced force control system using industrial robots is relativelylimited. Using force controlled robot systems expands the possibility of what canbe done with industrial robots.Previously a force feedback system for a standard industrial robot from ABBhas been developed. The system is developed towards the aircraft industry, where amounted drill machine on the robot has to fulfill the requirements in robot drillingin aircraft structures. This thesis presents experimental results and improvementsof this industrial robot system. Mechanical modifications and tests of a new endeffector are analyzed.</p>

Trots en ökad efterfrågan i samhället på insatser för att stötta nyanlända i språkutveckling, och därmed även att ta sig in på arbetsmarknaden, finns i Sverige begränsad forskning kring handledning av nyanlända inom industrisektorn. Syftet med denna studie är att bringa kunskap i förutsättningar för arbetsplatslärande hos nyanlända inom industrisektorn, med fokus på språkinlärning. Detta görs genom att undersöka följande frågeställningar; Hur föreskrivs yrkesintroduktion gå till? Hur förhåller sig handledare till processer för nyanländas språkinlärning? Hur förhåller sig handledare till processer för inkludering av nyanlända? Vilka förutsättningar ger yrkesintroduktioner för nyanländas arbetsplatslärande inom företagen?Metoderna för att undersöka fenomenet är dels kvalitativa intervjuer av sex handledare för nyanlända på yrkesintroduktioner på tre olika företag inom industrisektorn, samt en text- och dokumentanalys av fyra stöddokument som har tagits fram av Delegationen för arbetsplatslärande vid yrkesintroduktionsanställningar (YA-delegationen) kring handledning av nyanlända.   Genom ett teoretiskt ramverk baserat på Etienne Wengers teori om gränsland och mäklarskap inom ”Communities of Practices” (2000) tolkas resultaten från undersökningarna. Några av de slutsatser som dras är att handledarna på företagen främst arbetar med praktisk upplärning av arbetsuppgifter och språkinlärning som fokuserar på inlärning av enskilda yrkesbegrepp. Djupare diskussioner kring normer och värderingar samt ”mjuka värden” hindras på grund av bristande språkkunskaper hos de nyanlända. Bristande kunskap i hur gemensamma aktiviteter för kunskapsutbyten kan ske utmärker även handledarskapet, och förslag på sådana aktiviteter saknas även i stöddokumenten. En sista slutsats är att om varken staten eller företagen själva kan stötta handledare i hur olika människors kunskaper kan tas tillvara på och hur mångfald ska utnyttjas så blir språket inom industrier inte bara en säkerhetsfråga, utan en samhällsfråga. / Despite an increased demand in society for effortsto support newly arrived immigrants in language development, and getting a way in to the labor market, there is a limited research in Sweden on mentorship of immigrants in the industrial sector. The aim of this study is to bring knowledge into the prerequisites for workplace learning among immigrants in the industrial sector, with a focus on language learning. This is done by examining the following questions;How are professional introductions precribed to be implemented? How do supervisors relate to processes for language learning of the immigrants? How do supervisors relate to processes for inclusion of immigrants? What are the prerequisites for professional introductions for immigrant´s workplace learning within the companies?The methods for examining this phenomenon are partly qualitative interviews of six mentors of immigrants at professional introductions at three different companies in the industrial sector, as well as a document analysis on four steering documents that have been provided by the YA-delegation.   The results of the study are interpreted through a theoretical framework based on Etienne Wenger's (2000) theory of boarders and broakers within the theory of ”Communities of Practice”. Some of the conclusions that are drawn are that the mentors at the companies mostly work with practical training of tasks, and language learning that focuses on separate technical terms. Deeper discussions on norms and values​ ​​are hindered by the lack of broader language skills of the immigrants. Lack of knowledge in how joint activities for knowledge sharing can be taken place characterizes the mentorships, and this aspect is also lacking in the state’s governance documents. One final conclusion is that if neither the state nor the companies themselves can support mentors in how different people's knowledge can be utilized and how diversity should be utilized, the language within industries will not only be a security issue, but a social issue.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A crescente preocupaÃÃo em relaÃÃo Ãs questÃes ambientais, somada à necessidade de promover o desenvolvimento sustentÃvel, tornou emergente a discussÃo sobre a avaliaÃÃo e a reduÃÃo dos impactos ambientais relacionados Ãs atividades industriais. Muitos dos mÃtodos de avaliaÃÃo de impactos ambientais aplicados atualmente, para diversos tipos de empreendimentos, contam com um grau considerÃvel de subjetividade. Este trabalho tem como objetivo o desenvolvimento de um mÃtodo quantitativo para a avaliaÃÃo de impactos ambientais, tendo em vista a pouca contribuiÃÃo cientÃfica nesta Ãrea de estudos, especialmente no Estado do CearÃ. O mÃtodo desenvolvido admite a aplicaÃÃo de indicadores ambientais, organizados por categorias. Aos indicadores, associam-se funÃÃes matemÃticas que possibilitam a obtenÃÃo de um valor adimensional, denominado de Ãndice de qualidade ambiental. Esses Ãndices sÃo combinados a partir de mÃdias aritmÃticas atà a determinaÃÃo de um Ãnico valor numÃrico, representante da condiÃÃo ambiental da organizaÃÃo. A aplicaÃÃo prÃtica do mÃtodo foi realizada em uma indÃstria do ramo tÃxtil, a partir da escolha de 18 indicadores, agrupados em trÃs categorias: eficiÃncia de recursos, efluentes e emissÃes gasosas. Os resultados obtidos revelam a boa aderÃncia do mÃtodo Ãs variaÃÃes do processo industrial, possibilitando aos gestores ambientais da organizaÃÃo a tomada de decisÃes baseadas em fatos, com simplicidade e significativa reduÃÃo da subjetividade em relaÃÃo à anÃlise dos impactos ambientais considerados. / The increasing concerning about environmental matters, added to the necessity of promoting sustainable development, transformed the discussion about evaluation and reduction of environmental impacts, related to industrial activities, in an emergent issue. Several methods currently applied to evaluate environmental impacts, for various types of enterprises, have considerable subjectivity. The objective of this work is to achieve the development of a quantitative method for the evaluation of environmental impacts; hence there are few scientific studies in this subject, mainly in Ceara State. The method developed allows the application of environmental indicators, divided in category sets. Mathematical functions are associated to these indicators in order to obtain non-dimensional values called environmental quality indexes. These indexes are combined using arithmetical means until the determination of a unique numerical value, which is representative of the organizationâs environmental performance. Practical application of the method was conducted in a textile industry, in which were elected 18 indicators, grouped in three categories: resources efficiency, effluents and gas emissions. Obtained results show good effectiveness of the method concerning to the industrial intrinsic process variations, giving environmental managers the possibility of making fact based decisions, in a simple way and with significant reduction of the subjectivity related to the analysis of the environmental impacts considered.

Industrial robots have been used for a long time in the industry. Despite this thedevelopment of advanced force control system using industrial robots is relativelylimited. Using force controlled robot systems expands the possibility of what canbe done with industrial robots.Previously a force feedback system for a standard industrial robot from ABBhas been developed. The system is developed towards the aircraft industry, where amounted drill machine on the robot has to fulfill the requirements in robot drillingin aircraft structures. This thesis presents experimental results and improvementsof this industrial robot system. Mechanical modifications and tests of a new endeffector are analyzed.

Orientador: Rafael de Brito Dias / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-21T13:43:57Z (GMT). No. of bitstreams: 1 Faria_JanainaElisaPattide_M.pdf: 2319389 bytes, checksum: 7595de5c7ebdd761885688d44470db07 (MD5) Previous issue date: 2012 / Resumo: O objetivo geral desta Dissertação de Mestrado é apresentar elementos históricos, jurídicos, econômicos e políticos concernentes à propriedade intelectual, contribuindo para uma reflexão crítica a respeito da visão atualmente naturalizada do papel benéfico desta relevante instituição social. No primeiro capítulo, busca-se articular aspectos teóricos da funcionalidade da propriedade intelectual para o capitalismo - especialmente das patentes - com a trajetória histórica dos mecanismos que asseguram o estatuto de propriedade privada de conhecimentos e criações intelectuais. A ascensão do capitalismo monopolista no fim do século XIX e a assinatura da Convenção da União de Paris (CUP) constituem o ponto de partida da análise histórica. Destaca-se o papel dos EUA como catalisador das principais transformações internacionais nesse campo, com particular vigor no período neoliberal, o que culminou na assinatura do Acordo TRIPS (Trade-Related Aspects of Intellectual Property Rights) da Organização Mundial de Comércio (OMC). O segundo capítulo aborda alguns impactos da homogeneização internacional de direitos de propriedade intelectual (DPIs) estabelecida pelo TRIPS para a periferia do capitalismo, salientando a coerção política e econômica exercida pelos EUA para a adoção de regras mais rígidas do que as exigidas no Acordo. Elucida-se também como ocorreu o processo político de internalização do TRIPS no Brasil e as transformações dele decorrentes no que se refere aos pagamentos de contratos de transferência de tecnologia. O terceiro capítulo, por sua vez, ilustra o conflito mundial gerado pelo TRIPS em um setor produtivo específico: a indústria farmacêutica. São apresentados argumentos que contribuem para a reflexão sobre patentes farmacêuticas, inovação, produção e acesso a medicamentos. O comportamento da indústria farmacêutica com operação no Brasil e do acesso a medicamentos no país também são abordados no terceiro capítulo. O quarto e último capítulo deste trabalho explora as recentes estratégias adotadas pelos países centrais para elevar o nível internacional de DPIs por meio principalmente da ampliação das regras concernentes à observância desses direitos, destacando três importantes iniciativas: Regulamento CE 1383/2003 da União Européia, Força-Tarefa Anticontrafação (IMPACT) da Organização Mundial de Saúde e o Acordo Comercial Anticontrafação (ACTA). Aponta-se que as novas regras são em sua vasta maioria negociadas em fóruns onde países periféricos têm pouca ou nenhuma chance de se manifestarem a respeito de normatizações que os impactam direta ou indiretamente. Em linhas gerais, o alicerce deste trabalho é a relação de exploração econômica e de dominação política entre os países centrais e periféricos; relação esta que condiciona as regras internacionais de propriedade intelectual a fim de favorecer os países que são o centro gravitacional do capitalismo / Abstract: The overall goal of this Master's Dissertation is to present historical, legal, economic and political elements concerning intellectual property in order to contribute to a critical reflection about the current naturalized vision of the beneficial role played by this social institution. In the first chapter we intend to articulate the theoretical aspects of the functionality of intellectual property in capitalism - especially patents - with the historical trajectory of the mechanisms that ensure the status of private ownership of knowledge and intellectual creations. The rise of monopoly capitalism in the late nineteenth century and the signing of the Paris Convention are the starting point of the historical analysis. Noteworthy is the U.S. role as a catalyst for major international changes in this field with particular strength in the neoliberal period, culminating in the signing of the Trade-Related Aspects of Intellectual Property Rights Agreement (TRIPS) of the World Trade Organization (WTO). The second chapter discusses some impacts of the international homogenization of intellectual property rights (IPRs) established by TRIPS to peripheral countries, highlighting the political and economic coercion exerted by the U.S. for the adoption of rules stricter than those required by the Agreement. It also elucidates the political process of the internalization of TRIPS in Brazil and some consequences in regard to payments for technology transfer contracts. The third chapter, in turn, illustrates the worldwide conflict generated by TRIPS in a specific production sector: the pharmaceutical industry. It presents arguments that contribute to the debate on pharmaceutical patents, innovation, production and access to medicines. The behavior of the pharmaceutical industry with operations in Brazil and access to medicines in the country are also covered in the third chapter. The fourth and final chapter of this work explores the recent strategies adopted by developed countries to raise the international level of IPRs primarily through the expansion of enforcement rules. The focus is given to three initiatives of the 'enforcement movement': EC Regulation 1383/2003 of the European Union, International Medical Products Anti-Counterfeiting Taskforce of the World Health Organization (IMPACT/ WHO) and the Anti-Counterfeiting Trade Agreement (ACTA). It is pointed out that the new rules are overwhelmingly negotiated in forums where peripheral countries have little or no chance to express their interests regarding regulations that impact them directly or indirectly. In general, the foundation of this Master's Dissertation is the relationship of economic exploitation and political domination between central and peripheral countries; in a large extent, this relationship designs the international intellectual property rules in order to favor countries that are the gravitational center of capitalism / Mestrado / Politica Cientifica e Tecnologica / Mestra em Política Científica e Tecnológica

Control and monitoring networks often operate on AC/DC power systems. DC batteries and chargers are commonly used on industrial plants as auxiliary DC power systems for these control and monitoring networks. The energy demand and load profiles for these control networks differ from application to application. Proper design, sizing, and maintenance of the components that forms part of the DC control power system are therefore required. Throughout the load profile of a control and monitoring system there are various peak currents. The peak currents are classified as inrush and momentary loads. These inrush and momentary loads play a large role when calculating the required battery size for an application. This study investigates the feasibility of using supercapacitors in conjunction with batteries, in order to reduce the size of the required battery capacity. A reduction in the size of the required battery capacity not only influences the cost of the battery itself, but also influences the hydrogen emissions, the physical space requirements, and the required rectifiers and chargers. When calculating the required size batteries for an auxiliary power system, a defined load profile is required. Control and monitoring systems are used to control dynamic processes, which entails a continuous starting and stopping of equipment as the process demands. This starting and stopping of devices will cause fluctuations in the load profile. Ideally, data should be obtained from a live plant for the purpose of defining load profiles. Unfortunately, due to the economic risks involved, installing data logging equipment on a live industrial plant for the purpose of research, is not allowed. There are also no historical data available from which load profiles could be generated. In order to evaluate the influence of supercapacitors, complex load profiles are required. In this study, an alternative method of defining the load profile for a dynamic process is investigated. Load profiles for various applications are approximated using a probabilistic approach. The approximation methodology make use of plant operating philosophies as input to the Markov Chain Monte Carlo simulation theory. The required battery sizes for the approximated profiles are calculated using the IEEE recommended practice for sizing batteries. The approximated load profile, as well the calculated battery size are used for simulating the auxiliary power system. A supercapacitor is introduced into the circuit and the simulations are repeated. The introduction of the supercapacitor relieves the battery of the inrush and momentary loads of the load profile. The battery sizing calculations are repeated so as to test the influence of the supercapacitor on the required battery capacity. In order to investigate the full influence of adding a supercapacitor to the design, the impact on various factors are considered. In this study, these factors include the battery size, charger size, H2 extraction system, as well as maintenance requirements and the life of the battery. No major cost savings where evident from the results obtained. Primary reasons for this low cost saving are the fixed ranges in which battery sizes are available, as well as conservative battery data obtained from battery suppliers. It is believed that applications other than control and monitoring systems will show larger savings. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015

Control and monitoring networks often operate on AC/DC power systems. DC batteries and chargers are commonly used on industrial plants as auxiliary DC power systems for these control and monitoring networks. The energy demand and load profiles for these control networks differ from application to application. Proper design, sizing, and maintenance of the components that forms part of the DC control power system are therefore required. Throughout the load profile of a control and monitoring system there are various peak currents. The peak currents are classified as inrush and momentary loads. These inrush and momentary loads play a large role when calculating the required battery size for an application. This study investigates the feasibility of using supercapacitors in conjunction with batteries, in order to reduce the size of the required battery capacity. A reduction in the size of the required battery capacity not only influences the cost of the battery itself, but also influences the hydrogen emissions, the physical space requirements, and the required rectifiers and chargers. When calculating the required size batteries for an auxiliary power system, a defined load profile is required. Control and monitoring systems are used to control dynamic processes, which entails a continuous starting and stopping of equipment as the process demands. This starting and stopping of devices will cause fluctuations in the load profile. Ideally, data should be obtained from a live plant for the purpose of defining load profiles. Unfortunately, due to the economic risks involved, installing data logging equipment on a live industrial plant for the purpose of research, is not allowed. There are also no historical data available from which load profiles could be generated. In order to evaluate the influence of supercapacitors, complex load profiles are required. In this study, an alternative method of defining the load profile for a dynamic process is investigated. Load profiles for various applications are approximated using a probabilistic approach. The approximation methodology make use of plant operating philosophies as input to the Markov Chain Monte Carlo simulation theory. The required battery sizes for the approximated profiles are calculated using the IEEE recommended practice for sizing batteries. The approximated load profile, as well the calculated battery size are used for simulating the auxiliary power system. A supercapacitor is introduced into the circuit and the simulations are repeated. The introduction of the supercapacitor relieves the battery of the inrush and momentary loads of the load profile. The battery sizing calculations are repeated so as to test the influence of the supercapacitor on the required battery capacity. In order to investigate the full influence of adding a supercapacitor to the design, the impact on various factors are considered. In this study, these factors include the battery size, charger size, H2 extraction system, as well as maintenance requirements and the life of the battery. No major cost savings where evident from the results obtained. Primary reasons for this low cost saving are the fixed ranges in which battery sizes are available, as well as conservative battery data obtained from battery suppliers. It is believed that applications other than control and monitoring systems will show larger savings. / MIng (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015

3D-Druck durch computergesteuerte selektive Betonablage ist der am häufigsten verwendete Ansatz im Kontext der additiven, digitalen Fertigung im Betonbau. Dieses schalungsfreie digitale Verfahren ermöglicht ein schnelles, wirtschaftliches Bauen und bietet einen großen architektonischen Gestaltungsspielraum. Um die Möglichkeiten der 3D-Druck-Technologie im Betonbau zu entfalten, müssen die rheologischen und mechanischen Eigenschaften von Beton exakt charakterisiert werden und so eingestellt, dass sie mit aus den Prozessparametern resultierenden Anforderungen an das Material übereinstimmen. Des Weiteren ist die inhärente Anisotropie der 3D-gedruckten Elemente aufgrund der schichtweisen Herstellung und Bildung von Arbeitsfugen zu beachten. Um die aus den Prozessparametern resultierenden Anforderungen zu erfüllen und Schwachstellen zu vermeiden, sollten die druckbare Betone bestimmte, genau kontrollierbare rheologische Eigenschaften wie statische Fließgrenze und ihre zeitliche Entwicklung (aufgrund von strukturellen Aufbau- und Hydratationsreaktionen) aufweisen. Die komplexenund teilweise widersprüchlichen Materialanforderungen erfordern umfangreiche experimentelle Untersuchungen. Dies ist eine große Herausforderung, da es keine Standardtestmethoden zur Materialcharakterisierung von druckbarem Beton gibt. Die vorliegende Arbeit fokussiert auf die Erarbeitung einer praxistauglichen Vorgehensweise zur Festlegung, Einstellung und Prüfung der erforderlichen Materialeigenschaften von frischem und erhärtendem Beton. Folgende wesentliche Anforderungen an druckbare Betone wurden untersucht: die Pumpbarkeit, die Extrudierbarkeit, die Verbaubarkeit sowie die Leistungsfähigkeit der Verbunds zwischen den Schichten. Im Ergebnis der Arbeiten wurden Methoden zur a) dehnungsbasierten Messung des Strukturaufbaus, b) rechnerischen Abschätzung von Pumpendruck, c) Inline-Charakterisierung der Extrudierbarkeit, d) praxisorientierten Ermittlung der Verbaubarkeit und e) mikro- und makroskopischen Untersuchungen der Grenzflächeneigenschaften der Schichten entwickelt. In den experimentellen Untersuchungen wurden u.a. ein Beton-3D-Drucker mit einer Exzenterschneckenpumpe, ein Couette-Rheometer mit zylindrischer Messgeometrie, ein RAM Extruder und ein Rasterelektronenmikroskop eingesetzt, um die entwickelten druckbaren, feinkörnigen, hochfesten Betone systematisch zu charakterisieren. Die Analysen der umfangreichen experimentellen Ergebnisse zeigten, dass der Strukturaufbaudes frischen Zementleims mit dem Ansatz der konstanten effektiven Dehnung ermittelt werdenkann, diese hinreichend groß sein muss, um den statische Fließgrenze zu erreichen (Strukturbruch). Die Simulationsergebnisse aus dem entwickelten CFD-Modell (computational fluid dynamics) für Virtual SLIPER (slidingpiperheometer) korrelierten mit experimentellen Messungen. Im CFD-Modell wurde eine Gleitschicht zwischen Wandung und Kernbeton implementiert und deren Viskosität mit dem Krieger-Dougherty-Modell berechnet. Die Gültigkeit der vorgeschlagenen Inline-Charakterisierung der Extrusion wurde durch den Vergleich der Ergebnisse von RAM-Extrusion- und Viskometerprüfungen nachgewiesen. Die spezifische Extrusionsenergie, d.h. der Energieverbrauch pro extrudierte Einheitsvolumen, stieg mit zunehmender Fließgrenze und plastischer Viskosität des Betons. Die Parameter zur Beschreibung der Verbaubarkeit wurden mit einem praxisorientierten Ansatz identifiziert. Das vorgeschlagene Modell berücksichtigt Maschinen-, Arbeits-, Materialkosten sowie die Art des 3D-Drucks. Die Eigenschaften des Verbunds zwischen den Schichten hängen stark vom Zeitintervall zwischen der Ablage der Schichten, der Bindemittelzusammensetzung und der Porosität/Rauheit des Substrats ab. Eine ungünstige Parameterwahl kann zu fatalen Folgen führen. Der teilweise Ersatz von Portlandzement durch puzzolanische Zusatzstoffe führte zu einem schnelleren Strukturaufbau, eines verbesserten Zwischenschichtverbundes und günstigen mechanischen Eigenschaften. Die in dieser Arbeit entwickelte Werkzeuge zur Materialcharakterisierung und die damit ermittelten Ergebnisse schaffen eine Grundlage für eine genaue und zuverlässige Materialcharakterisierung zementgebundener Materialien für den Einsatz beim 3D-Druck durch selektive Ablage. / Extrusion-based 3D-printing — also referred to as digital construction (DC) — involves automated layer-by-layer deposition of 3D-printable cement-based materials (3PCs). DC enables speedy, economic and formwork-free construction in addition to quasi-unlimited architectural design flexibility. To ensure these advancements with DC, the rheological and mechanical properties of 3PCs need to be accurately measured and optimised according to the technological requirements. Inherently, the 3D-printed elements can reveal weak layer-to-layer interfaces, which form the weakest links in the entire structure and imply pronounced anisotropy. To fulfil the process requirements and to prevent weak bonds, the 3PCs should exhibit particular, precisely controllable rheological properties, such as static yield stress and its development in time due to structural build-up. The complex and partly contradictory material requirements of 3PCs necessitates comprehensive experimental investigations. This is a great challenge since there are no standard test methods for the material characterisation of 3PCs. In this research, while following an overarching aim of developing high-performance 3PCs for on-site DC, the author focused on material characterisation. The primary requirements to 3PCs — pumpability, extrudability, buildability and layer-to-layer bond — are investigated. The deliverables are methods for a) strain-based measurement of structural build-up, b) computationally estimating pumping pressures, c) inline extrudability characterisation, d) practice-oriented determination of buildability test parameters and e) micro- and macroscopic insights on layer-to-layer interface properties. A 3D-printing test device with a progressive cavity pump, a concentric cylinder Couette rheometer, ram extruder and scanning electron microscope were the major devices applied to systematically characterise the printability of developed fine-grained high-strength 3PCs. The extensive analyses of the experimental results revealed that structural build-up can be characterised with constant effective strain approach. To do so, this effective strain must be high enough to ensure flow-onset. Simulation results obtained using the developed CFD (computation fluid dynamics) model called virtual Sliper (sliding pipe rheometer) correlated with experimental measurements. Lubricating layer was implemented into the CFD model and its viscosity could be calculated using Krieger-Dougherty model. Comparative analyses of ram-extrusion and viscometer tests substantiated the significance of the proposed inline extrudability quantification method for 3PCs. The unit extrusion energy, i.e. energy consumed per extruded unit volume of 3PC, increased with increasing yield stress and plastic viscosity of 3PCs. Buildability tests’ parameters were identified with a practice-oriented approach. The proposed model takes machine, labour, material costs and DC approach type into consideration. Layer-to-layer interface properties were shown to be highly sensitive to time interval between subsequent layers, binder composition, and substrate porosity/roughness. An improper choice of parameters can lead to fatal consequences. Furthermore, it was demonstrated that partial replacement of Portland cement with supplementary cementitious materials causes high structuration rate (structural build-up), superior interface properties and satisfactory mechanical performance. Developed test methods and the obtained results establish a basis for accurate and reliable material characterisation of cementitious materials in the context of extrusion-based digital construction.

In recent years the steelmaking industry has been subjected to continuous attempts to improve its production route. The main goals has been to increase the competitiveness and to reduce the environmental impact. The development of predictive models has therefore been of crucial importance in order to achieve such optimization. Models are representations or idealizations of reality which can be used to investigate new process strategies without the need of intervention in the process itself. Together with the development of Industry 4.0, Machine Learning (ML) has turned out as a promising modeling approach for the steel industry. However, ML models are generally difficult to interpret, which makes it complicated to investigate if the model accurately represents reality. The present work explores the practical usefulness of applied ML models in the context of the secondary metallurgy processes in steelmaking. In particular, the application of interest is the prediction of the liquid steel temperature after the vacuum treatment step in the Vacuum Tank Degasser (VTD). The choice of the VTD process step is related to its emerging importance in the SSAB Oxelösund steel plant due to the planned future investment in an Electric Arc Furnace (EAF) based production line. The temperature is an important parameter of process control after the vacuum treatment since it directly influences the castability of the steel. Furthermore, there are not many available models which predict the temperature after the vacuum treatment step. The present thesis focuses first on giving a literature background of the statistical modeling approach, mainly addressing the ML approach, and the VTD process. Furthermore, it is reported the methodology behind the construction of the ML model for the application of interest and the results of the numerical experiments. All the statistical concepts used are explained in the literature section. By using the described methodologies, several findings originated from the resulting ML models predicting the temperature of the liquid steel after the vacuum treatment in the VTD.A high complexity of the model is not necessary in order to achieve a high predictive performance on the test data. On the other hand, the data quality is the most important factor to take into account when improving the predictive performance. Itis fundamental having an expertise in both metallurgy and machine learning in order to create a machine learning model that is both relevant and interpretable to domain experts. This knowledge is indeed fundamental for the selection of the input data and the machine learning model framework. Crucial information for the predictions result to be the heat status of the ladle as well as the stirring process time and the temperature benchmarks before and after the vacuum steps. However, to draw specific conclusions, a higher model predictive performance is needed. This can only be obtained upon a significant data quality improvement. / Stålindustrin har under de senaste åren ständigt förbättrat sin produktionsförmåga som i huvudsak har bidragit till ökad konkurrenskraft och minskad miljöpåverkan. Utvecklingen  av  prediktiva  modeller  har  under  denna  process  varit  av  avgörande betydelse för att uppnå dessa bedrifter. Modeller är representationer eller idealiseringar av verkligheten som kan användas för att utvärdera nya processtrategier utan att åberopa  ingrepp  i  själva  processen.    Detta  sparar  industrin  både  tid och pengar.   I takt  med  Industri  4.0  har  maskininlärning  blivit  uppmärksammad  som ett ytterligare modelleringsförfarande inom stålindustrin. Maskininlärningsmodeller är dock generellt svårtolkade, vilket gör det utmanande att undersöka om modellen representerar verkligheten. Detta arbete undersöker den praktiska användningen av maskininlärningsmodeller inom sekundärmetallurgin på  ett  svenskt  stålverk.    Tillämpningen  är  i  synnerhet av   intresse   för   att   kunna   förutspå   temperaturen   hos   det   flytande   stålet   efter vakuumbehandlingssteget  i  VTD-processen. Denna  process  valdes  eftersom den är av  stor  betydelse  för  framtida  ståltillverkning  hos  SSAB  i  Oxelösund. Detta är primärt  på  grund  utav  att  SSAB  kommer  att  investera  i  en ljusbågsugnsbaserad produktionslinje.   Temperaturen är en viktig processparameter eftersom den direkt påverkar   stålets   gjutbarhet. Utöver   detta   har   inga   omfattande   arbeten   gjorts gällande  att  förutspå  temperaturen  efter vakuumbehandlingssteget  med  hjälp av maskininlärningsmodeller. Arbetet presenterar först en litteraturbakgrund inom statistisk modellering med fokus på maskininlärning och VTD-processen.  Därefter redovisas metodiken som använts för att skapa  maskininlärningsmodellerna  som  ligger  till  grund  för  de  numeriska experimenten samt resultaten. Genom att använda de beskrivna metoderna härrörde flera fynd från de skapande maskininlärningsmodellerna. En hög grad av komplexitet är inte   nödvändig   för   att   uppnå   en   hög   prediktiv   förmåga   på   data   som   inte använts  för  att  anpassa  modellens  parametrar.   Å  andra  sidan  är  datakvalitén den viktigaste faktorn om man ämnar att förbättra den prediktiva förmågan hos modellen. Utöver  detta  är  det  av  yttersta  vikt  att  ha  kompetens  inom  både  metallurgi  och maskininlärning för att skapa en modell som är både relevant och tolkbar för experter inom  området  processmetallurgi. Ideligen  är  kunskap  inom  processmetallurgi grundläggande för val av indata och val av maskininlärningsalgoritm. Under analysen av maskininlärningsmodellerna upptäcktes det att skänkens värmestatus, omrörningstiden i processen, samt temperaturriktmärkena före och efter vakuumstegen var de mest avgörande variablerna för modellens prediktiva förmåga. För att kunna dra specifika slutsatser behöver modellen ha en högre prediktiv förmåga. Detta kan endast erhållas efter en betydande förbättring av datakvalitén.