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The development of a piano-recorder systemDamm, Bernt W January 1993 (has links)
Thesis (Masters Diploma (Electrical Engineering)--Cape Technikon, Cape Town, 1993 / This thesis describes the development and design of a pianorecorder
system. This system makes it possible to record the
notes played on a piano onto a computer disk. The records can
then be used for the manufacturing of pianola rolls.
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Whole life cost methods for computer systemsBradley, Malcolm January 1998 (has links)
This thesis provides an analysis of cost of ownership issues and techniques, and provides the supporting data to enable future system designers to make rational decisions on design options. It represents the experience gained whilst collecting cost and cost relationship data in the Rolls-Royce group over a period or more than four years. This, in a time of continuous change, in both the company and the wider IT industry. The thesis is arranged in chapters, each representing a milestone conference or journal paper. The exception to this is chapter Il- the conclusion and summary of the work in the thesis. The Chapter topics cover firstly the background of whole life cost and the aims and objectives of the research. A relationship between whole life cost and quality is considered and why whole life cost is a useful measure of quality. This is examined in practical terms of tools and methods. Case studies are used to illustrate the measurement and use of whole life cost. The impact of obsolescence risk is next considered, identifying the causes and implications of obsolescence. Case studies are used to show how the IT help desk can be used to identify and reduce whole life costs both in a deterministic and a probabilistic approach. This is followed by an examination of the costs of database systems at Rolls-Royce and Associates. Case studies of database systems are also used to show the need to collect in service data, and genetic algorithms are shown to be a useful tool for analysing the data. Whole life costing techniques applied to engineering systems at Rolls-Royce is examined. It is shown that a reliability centred maintenance database is a cost effective tool in collecting data. Network monitoring software is shown to be an effective tool for reducing the cost of ownership of IT systems. The overall conclusion is that whole life cost techniques have been shown to work for computer based systems, further work in this area is still needed to enable costs to be fully understood and optimised.
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Equipment for bearing housing change of work rolls in a steckel mill / Utrustning för byte av lagerhus på arbetsvalsarna i ett steckelverkNorman, Joakim January 2015 (has links)
Outokumpu Stainless AB operates in the production and development of stainless steels. In their hot rolling mill in Avesta there is a need to introduce an equipment to shift bearing housings on the steckel mill work rolls. Today this is accomplished manually with an overhead crane, jack, sledgehammer and pry-bar. It causes strain on the operators and the equipment may be damaged in the process.On behalf of Outokumpu Stainless AB, Bilfinger started this project as a thesis with the objective to develop a design proposal for a machine that meets the requirements for an easier and better handling of the bearing housing changes. In this thesis the author presents some concepts on how the machine could work, analysis of forces which occur when the roll assembly is placed on the table, a simple model to estimate the needed force to remove the bearing housing from the work roll as well as force and FEM analysis of the machine. The result was a machine consisting of a table to place the roll upon and two pullers, one for each bearing housing, which brings the bearing housing with it when actuated by a hydraulic cylinder. The machine meets all of the set requirements except for the production cost and the power of the hydraulic cylinder while retracting (30% lower). A rough estimation of the production and installation cost is estimated at just over 1 MSEK. / Outokumpu Stainless AB är verksamma inom tillverkning och utveckling av rotsfria stål. I deras varmvalsverk i Avesta finns ett behov att införa en utrustning för att enkelt byta lagerhusen på steckel valsverkets arbetsvalsar. Idag förs detta manuellt med travers, domkraft, slägga och spett. Det ger slitage på operatörer och även utrustningen kan skadas i denna process. På uppdrag av Outokumpu Stainless AB har Bilfinger startat detta projekt som ett examensarbete med målsättning att ta fram ett konstruktionsförslag för en maskin som uppfyller kraven på en smidigare och bättre hantering av lagerhusbytena. I detta arbete presenteras några koncept på hur maskinen skulle kunna fungera, några analyser av krafter som uppstår när vals och lagerhus placeras i sitt stativ, en enklare modell för att uppskatta den kraft som krävs för att ta av lagerhusen från valsen samt kraft och FEM analyser av maskinen. Resultatet blev en maskin som består av ett stativ att placera valsen med lagerhusen på samt två avtagare, en för varje lagerhus som drar med lagerhuset då den påverkas av en hydraulisk cylinder. Maskinen uppfyller alla satta krav förutom produktions pris och kraften i hydraulikcylindern då den dras in (30% lägre). En grov uppskattning av produktions och installations kostnad beräknas till lite över 1 MSEK.
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Tredagars föräldraaktiv inskolning av små barn : En vetenskaplig essä utifrån anknytningsteoretiska perspektivPersson, Elena, Fonseka, Geeshani January 2016 (has links)
In this essay, we have used scientific methodology as means to correlate our reflections to scientific literature and theory. The purpose of the essay is to examine the three-day parent active introduction method and its influence on children, parents and teachers. We have interviewed four teachers from different pre-schools in Stockholm in order to gain more knowledge from other teachers point of view on our research. The essay starts with two different firsthand scenarios where we describe three-day parent active introduction. In one of the two scenarios the children are introduced in a group and in the other the children are introduced individually. Throughout the writing of the essay it has brought thought to our minds about the length of the introduction and how that length effects the childrens attachment. Since we want to gain deeper understanding of the childrens attachment to the teachers we have based the essay upon John Bowlby's attachment theory. We have also taken in to consideration other views by other psychologists and theorists, who argue that children need time to build the relationship with the teachers during the introduction and that parents should not leave their children too early in pre-school. We believe that it is one of the most important moments for the childrens continued development to establish emotional bonds with the person who takes care of the child. In our essay we leverage the importance of the attachment theory has in relation to the moment when the children are being seperated from their parents for the first time. Then we examine the pre-school curriculum, if it in any way advocates the three-day parent active introduction. We also want to clarify what three-day parent active introduction is about. In addition we also are interested in finding out why threeday parent active introduction increased so much in popularity. We believe that the introduction has to start from the individual child and that the child needs time to build relationships. / Vi skriver denna uppsats i vetenskaplig essäform, där våra reflektioner kopplas till vetenskaplig litteratur och teori. Syftet med denna essä är att undersöka tredagars föräldraaktiv inskolning och dess påverkan på barn, föräldrar och pedagoger. För att få in andra pedagogers perspektiv i vår undersökning har vi intervjuat fyra pedagoger från olika förskolor i Stockholmsregionen. Essän inleds med två olika egenupplevda berättelser där vi beskriver tredagars föräldraaktiv inskolning. I den ena berättelsen skolas barnen in i grupp och i den andra skolas de in enskilt. När vi skriver våra berättelser väcks tankar kring inskolningsmetodens längd och hur längden påverkar barnens anknytning. Då vi vill nå djupare förståelse för barnens anknytning till pedagogerna, har vi i essän utgått ifrån psykoanalytikern John Bowlbys anknytningsteoretiska perspektiv. Samtidigt utgår vi även ifrån andra psykologer och teoretiker, som menar att barnen behöver tid på sig att bygga relation med pedagogerna under inskolningen och att föräldrarna inte bör lämna barnen för tidigt i förskolan. Vi tror att detta att knyta känslomässiga band med den närmaste omvårdnadspersonen är ett av de viktigaste momenten i barnens fortsatta utveckling. I vår essä lyfter vi frågan om anknytningens betydelse i separationsögonblicket den stunden då barnen skiljs från sina föräldrar för första gången. Därefter undersöker vi förskolans läroplan om den på något sätt förespråkar tredagars föräldraaktiv inskolning. Vi vill även tydliggöra vad tredagars föräldraaktiv inskolning går ut på. Vi vill också försöka ta reda på varför tredagars föräldraaktiv inskolning blivit så populärt. Vi menar att inskolningen måste utgå utifrån det individuella barnet och att barnet behöver tid på sig att skapa relationer.
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Mécanisme d'initiation du collage lors du laminage à chaud des aciers inoxydables ferritiques stabilisés / Initiation of sticking phenomenon in hot rolling of ferritic stainless steelsLuc, Emilie 20 December 2013 (has links)
Le laminage à chaud de l’acier inoxydable est une étape du procédé de fabrication agissant significativement sur la qualité de surface des produits. Les nuances ferritiques stabilisées sont largement utilisées dans les applications automobiles et de décoration mais sont concernées par le phénomène de collage à chaud. Ces nuances, ayant des résistances élevées en corrosion sèche et en fluage, sont riches en éléments tels que le Cr, le Nb ou le Ti, limitant aussi l’oxydation des brames lors du laminage. Or, l’oxydation maitrisée de la brame permet de protéger la surface du métal de tout contact direct avec les cylindres de laminage.Afin de comprendre l’initiation du collage, une première campagne d’étude sur la topographie et la dégradation de l’état de surface des cylindres a été réalisée. Il a été mis en évidence que l’initiation du collage ne serait pas du à des rayures d’usure en surface des cylindres et dont la profondeur serait supérieure à la couche d’oxyde, car la probabilité que la profondeur d’une rayure de cylindre soit plus importante que la couche d’oxyde est très faible.Ensuite, un banc d’essai reproduisant les conditions tribologiques de l’emprise du laminoir a été conçu afin de mieux appréhender les mécanismes à l’origine du collage. Etant donné l’importance de l’état de surface des brames et des cylindres, ce banc d’essai a permis de travailler sur des échantillons pris en production, permettant d’étudier la surface oxydée des tôles. Cette deuxième campagne d’étude a mis en évidence l’importance des oxydes de silicium sur l’adhérence partielle de la couche d’oxyde, ainsi que la relative hétérogénéité en épaisseur et en composition chimique. / Hot rolling of stainless steel is one of the most important steps in manufacturing process regarding surface quality of the product. Stabilised ferritic stainless steels are widely used in automotive and cosmetic appliances but are also concerned by sticking phenomenon. These grades, having high dry corrosion and creep resistance, are enriched in specific chemical elements such as Cr, Nb or Ti, limiting also slab oxidation during hot rolling. Nevertheless, the mastered oxidation of slab surface is a way to protect metal surface from direct contact with rolls.In order to better understand initiation of sticking, a first campaign was based on topography and rolls surface state wear analysis. This study revealed that sticking initiation is not due to the presence of roll scratches which depth is higher than oxide layer thickness. Indeed, the probability that roll scratches are deeper than oxide layer thickness is very low.In a second time, a pilot was designed, reproducing tribological conditions of a roll bite, to better understand mechanisms that initiate sticking. Keeping in mind the importance of rolls and slab surface state, this pilot is able to use specimen taking from industrial products, having the original oxide layer surface. This second study highlighted the major role of silicium oxides on scale adherence and the high heterogeneity of this scale layer in thickness and in chemical composition.
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Controle de nível em um processo de lingotamento contínuo de tiras-rolos duplos / not availableSantos, Josemar dos 22 June 2001 (has links)
O presente trabalho tem como objetivo explorar o uso de técnicas de controle avançado na indústria metalúrgica. O nível de aço é uma das variáveis mais críticas para a produção de chapas ou tiras de alta qualidade no processo de lingotamento contínuo de tiras baseados em rolos duplos. Para melhorar a qualidade da espessura das tiras utiliza-se em tanque intermediário submerso na piscina formada entre os rolos duplos. São propostas três técnicas e controle de \"fuzzy\" via modelos Mamdani e Takagi-Sugeno. O modelo Mamdani é desenvolvido com base no conhecimento experimental do processo. O modelo Takagi-Sugeno utiliza uma abordagem mais sistêmica para a resolução do problema, utilizando modelos locais (linearizados) da planta não-linear que descreve o nível e escoamento do aço no tanque intermediário. Os componentes do sistema de controle empregados são discutidos e especificados. São apresentados resultados de simulação utilizando os parâmetros reais de uma planta de lingotamento contínuo instalada no IPT São Paulo. As simulações realizadas mostram que as técnicas de controle sugeridas atendem as restrições da planta e são viáveis de implementação. / This work explores the use of advanced control techniques in the metallurgical industry. The molten steel level is one of the most critical to the production of high quality steel strips in strip casting process. The strip thickness uniformity can be improved using an intermediary tundish submerse into the pool formed between the two rotating rolls. Three control techniques are considered to control the intermediary tundish molten steel level: PID, feedback linearization and fuzzy logic via Mamdani and Takagi-Sugeno models. The Mamdani model is developed with base in the experimental knowledge of the process. The Takagi-Sugeno model uses a more systematic approach for the solution of the control problem using local models for the non-linear plant that describes the level and flow of the steel in the intermediary tundish. The components of the level control system are discussed and specified. Simulation results are presented considering the real system parameters of a strip casting plant installed at IPT São Paulo. The simulation results obtained show that the control techniques suggested satisfies the constraints on the plant and can be considered for implementation.
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Customer Needings : Finding the Relationship Gaps between Rolls Royce and their Industrial CustomersJohansson, Daniel, Fredriksson, Patrik January 2009 (has links)
<p><strong>Purpose </strong></p><p>The purpose of this thesis is to investigate to what extent Rolls Royce in Kristinehamn manages to fulfil their customer needings. By identifying gaps between offerings and needings, the authors will give recommendations on how Rolls Royce can increase their customers' satisfaction by providing them with what they need.</p><p> </p><p><strong>Method</strong></p><p>A qualitative research is used in the form of in-depth face-to-face- and telephone interviews. Eight such interviews have been conducted in this thesis; three interviews with representatives from Rolls Royce and five interviews with representatives from three of their customers.</p><p> </p><p><strong>Findings </strong></p><p>Many gaps have been found in the analysis of the empirical study. The most frequently discovered gaps are that; Rolls Royce should have better control over their sub-suppliers and Rolls Royce should agree on higher penalty fees for delay or poor quality. Further gaps have been found in which activities the customer wants to be relieved or enabled of.</p><p> </p><p><strong>Recommendations </strong></p><p>A figure of customer specific recommendations have been compiled through the findings. From this figure, general recommendations have been discovered that can, to some extent, represent all of Rolls Royce's customers.</p><p> </p>
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Customer Needings : Finding the Relationship Gaps between Rolls Royce and their Industrial CustomersJohansson, Daniel, Fredriksson, Patrik January 2009 (has links)
Purpose The purpose of this thesis is to investigate to what extent Rolls Royce in Kristinehamn manages to fulfil their customer needings. By identifying gaps between offerings and needings, the authors will give recommendations on how Rolls Royce can increase their customers' satisfaction by providing them with what they need. Method A qualitative research is used in the form of in-depth face-to-face- and telephone interviews. Eight such interviews have been conducted in this thesis; three interviews with representatives from Rolls Royce and five interviews with representatives from three of their customers. Findings Many gaps have been found in the analysis of the empirical study. The most frequently discovered gaps are that; Rolls Royce should have better control over their sub-suppliers and Rolls Royce should agree on higher penalty fees for delay or poor quality. Further gaps have been found in which activities the customer wants to be relieved or enabled of. Recommendations A figure of customer specific recommendations have been compiled through the findings. From this figure, general recommendations have been discovered that can, to some extent, represent all of Rolls Royce's customers.
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A study of the resistance of woven wool felts to liquid flowMacklem, James E. 01 January 1960 (has links)
No description available.
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Controle de nível em um processo de lingotamento contínuo de tiras-rolos duplos / not availableJosemar dos Santos 22 June 2001 (has links)
O presente trabalho tem como objetivo explorar o uso de técnicas de controle avançado na indústria metalúrgica. O nível de aço é uma das variáveis mais críticas para a produção de chapas ou tiras de alta qualidade no processo de lingotamento contínuo de tiras baseados em rolos duplos. Para melhorar a qualidade da espessura das tiras utiliza-se em tanque intermediário submerso na piscina formada entre os rolos duplos. São propostas três técnicas e controle de \"fuzzy\" via modelos Mamdani e Takagi-Sugeno. O modelo Mamdani é desenvolvido com base no conhecimento experimental do processo. O modelo Takagi-Sugeno utiliza uma abordagem mais sistêmica para a resolução do problema, utilizando modelos locais (linearizados) da planta não-linear que descreve o nível e escoamento do aço no tanque intermediário. Os componentes do sistema de controle empregados são discutidos e especificados. São apresentados resultados de simulação utilizando os parâmetros reais de uma planta de lingotamento contínuo instalada no IPT São Paulo. As simulações realizadas mostram que as técnicas de controle sugeridas atendem as restrições da planta e são viáveis de implementação. / This work explores the use of advanced control techniques in the metallurgical industry. The molten steel level is one of the most critical to the production of high quality steel strips in strip casting process. The strip thickness uniformity can be improved using an intermediary tundish submerse into the pool formed between the two rotating rolls. Three control techniques are considered to control the intermediary tundish molten steel level: PID, feedback linearization and fuzzy logic via Mamdani and Takagi-Sugeno models. The Mamdani model is developed with base in the experimental knowledge of the process. The Takagi-Sugeno model uses a more systematic approach for the solution of the control problem using local models for the non-linear plant that describes the level and flow of the steel in the intermediary tundish. The components of the level control system are discussed and specified. Simulation results are presented considering the real system parameters of a strip casting plant installed at IPT São Paulo. The simulation results obtained show that the control techniques suggested satisfies the constraints on the plant and can be considered for implementation.
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