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<p> Intercritically annealed steels, such as dual-phase steels, have found widespread use in automotive structural components due to their high strength and ductility. Elements such as Mn, Al and Si, added to improve the mechanical properties are selectively oxidized during heat treatment and limit the ability of the alloy to be reactively wet during continuous hot-dip galvanizing. Subsequently, a limit has been placed on the amount of alloy which can be used if the steel is to be subsequently galvanized. The specifics of this limit have not been explored in detail, nor has the mechanism of decreased wettability been well demonstrated in the literature other than to say that the galvanizing reaction is limited by oxides on the surface.</p> <p> Using a force balance, it is shown that the presence of MnO on the surface of steels greatly reduces the wettability with a typical galvanizing bath (Zn-0.2wt%Al, Fe-saturated, 460°C). Furthermore, it was determined that this is caused by the additional and rate-limiting step of aluminothermic reduction of the oxide layer with the bath Al, required for subsequent inhibition layer formation. By using a low pO2 during annealing, the wettability was improved by reducing the thickness of the MnO layer when compared to intermediate and industrially common values of pO2. Using a high pO2 also resulted in improved wettability since the internal oxide which was formed did not reduce the wettability since it was not exposed to the bath alloy.</p> <p> Improvements in hardenability were also explored via dilatometry showing that the formation of bainite is delayed with increasing Mn content, as well as a decrease in transformation temperatures from γ during cooling (i.e. Ms and Bs). At ~5wt% Mn, only the the transformation to αM could be observed. This opens the door to higher strength, galvanized steels - as well as possibly galvanized martensitic steels.</p> / Thesis / Master of Applied Science (MASc)

Permanent magnet brushless dc (PMBDC) and synchronous machines (PMSM) drives are favored in variable speed applications for their high efficiency operation. Energy efficiency improvement in such motor drives is of interest in recent times because of rising cost of energy. Accordingly, two current control options for improving efficiency of these drives are taken for study and they are; (i) injecting sinusoidal and non-sinusoidal currents in PMBDC machines and (ii) lowering switching frequency of inverter driving the PMSM but without having significant low ordered sidebands of currents. Both these methods are applicable to existing types of permanent magnet motors and hence do not upset their existing optimized designs. / Ph. D.

Det senaste årets granskning av lärosätens kvalitetssystem som genomfördes avuniversitetskanslersämbetet (UKÄ) visar att även högre utbildning behöver arbeta med sitt internakvalitetsarbete och att lärosätena behöver ta fram arbetssätt och metoder för att genomföra det.Syftet med det här arbetet var att bidra med kunskap om hur arbete med kvalitetsutveckling ser utinom högre utbildning samt att ta fram en modell för att arbeta med förbättrings ochkvalitetsutveckling inom lärarutbildning. Författaren deltog i ett projektarbete sominteraktionsforskare för att ta fram en modell för arbetet med förbättrings- och utvecklingsarbetetinom lärarutbildning. Den här studien har bidragit med kunskap om att högre utbildning idagarbetar med kvalitetsarbetet utifrån de riktlinjer som finns i Högskolelag, Högskoleförordning ochStandards and Guidelines for Quality Assurances in the European Higher Education Area (ESG).Slutsatsen var, att den modell för att arbeta med utvecklingsprojekt som togs fram i projektarbetet,behöver följa dessa lagar, förordningar och riktlinjer som anges i ESG och att arbetssättet imodellen bör vara cykliskt och kan utgå från PDSA. Vidare är slutsatsen att modellen med fördelkan ta utgångspunkt i offensiv kvalitetsutveckling och hörnstensmodellen och att om lärandetinom organisationen sker på alla nivåer kontinuerligt kan modellen stödja arbetet till en lärandeorganisation. Den här studien kan vara av intresse för andra som vill lära mer ominteraktionsforskning samt för lärosäten som står inför att utveckla sitt eget interna kvalitetsarbete. / The latest year's review of the higher education institutions' quality systems carried out by theuniversity chancellor's office (UKÄ) shows that even higher education needs to work with itsinternal quality work and that the higher education institutions need to develop working methodsand methods for implementing it. The purpose of this work was to contribute with knowledgeabout how work with quality development looks within higher education and to develop a modelfor working with improvement and quality development in teacher education. The authorparticipated in a project work as an interaction researcher to develop a model for the work onimprovement and development work in teacher education. This study has contributed with theknowledge that higher education today works with the quality work based on the guidelines foundin the Higher Education Act, the Higher Education Ordinance and the Standards and Guidelinesfor Quality Assurances in the European Higher Education Area (ESG). The conclusion was thatthe model for working with development projects developed in the project work must follow theselaws, regulations and guidelines stated in the ESG and that the working method in the modelshould be cyclical and can be based on PDSA. Furthermore, the conclusion is that the model canadvantageously be based on offensive quality development and the cornerstone model and that ifthe learning within the organization takes place at all levels continuously, the model can supportthe work of a learning organization. This study may be of interest to others who want to learnmore about interaction research and for higher education institutions that are faced withdeveloping their own internal quality work. / <p>2019-06-27</p>

Det här examensarbetet har fördjupat sig inom två områden inom kvalitetsledning. Det första området är ”ständiga förbättringar av processer”. Den andra är en ”mjuk sida” av kvalitetsledning, värderingarna.En enkät har tagits fram som ska kunna mäta stöd för olika värderingar. Motiveringen att göra det kan vara en önskan att skaffa sig en utgångspunkt i förbättringsarbetet för sitt arbete med förbättring av processer, inom en organisation eller företag. Denna enkät bör även lätt kunna modifieras för att bli användbar även för andra forskare eller organisationer för att mäta en utgångspunkt i sitt förbättringsarbete av processer.I detta arbete har utvärdering gjorts av två olika gruppers resultat för sex olika värderingarna (med enkät samt efterföljande intervjuer) som anses viktiga inom offensiv kvalitetsutveckling.Rapporten ger även förbättringsförslag till organisationen för utveckling av sitt arbete med ständiga förbättringar processer, för några av de värderingar som studien indikerade att stödet behövde utvecklas för. / This degree project has deepened into two areas within quality management (QM). The first area is “Continuous improvements of processes”. The second is a “soft side” of QM, the values.A survey has been developed that can measure support for different values to be able to provide a starting point for the improvement work with process improvement, within an organization or company. This survey can easily by using the same methodology as used in this work, being modified to be useful for other researchers or organizations.In this work, evaluation of results, from two different groups has been made, of support for six values (using questionnaires and subsequent interviews) as considered important in QM.The report also provides improvement suggestions to the organization for development of the work of “Continuous improvements of processes”, regarding some of the QM-values which is proposed to improve. / <p>2020-06-26</p>

This thesis analyses long term and short term environmental effects on geothermal power plant performance and discusses adaptive ways to improve performance. Mokai 1 geothermal power plant has been used as a case study for this investigation. Mokai 1 is a combined cycle plant where the binary cycles are air-cooled. The plant performance of an air-cooled binary cycle geothermal power plant is dependent on the environment (resource characteristics as well as weather conditions). For modelling such a power plant, two time scales are of interest: the yearly basis for aggregate plant performance for design and operations; and the daily basis for hourly plant performances for an accurate dispatch prediction. Adaptive methodology for long term performance improvement has been introduced in this work which would save money and effort in the future by keeping the provisions to adapt to changes in resource characteristics based on geothermal reservoir modelling. The investigation was carried out using a steady state computer simulator of Mokai 1 geothermal power plant. The steady sate simulator was built specifically for this work. The deviation in performance of various components is less than 5% compared to the original plant design. The model is very generic and it can be used for other plants with simple adaptation or can be used for future plant design. One of the main contributions of this work is an iterative method for modelling the environmental effect on short term performance on the air-cooled organic Rankine cycle. The ambient temperature is identified as the most influencing parameter on short term performance which influences the performance of the whole cycle in two ways. Firstly, by changing the equilibrium pressure inside the condenser, the turbine outlet pressure changes and hence, the turbine pressure ratio also changes. The turbine pressure ratio is a major parameter determining power generated by a turbine; therefore, the plant output is affected. Secondly, by changing the condenser outlet temperature with the ambient temperature, the pump inlet and outlet condition and consequently vaporizer equilibrium temperature and pressure are influenced. The developed method sought the equilibrium conditions of both condenser and vaporizer iteratively. In short, ORC cycle shifts on the T-s plane depending on the ambient temperature. This method iteratively seeks the shifted ORC on the T,s plane. Two case studies have been carried out to demonstrate the method. The developed method shows robustness and converges exponentially. The model is effective for cycles that use saturated vapour as well as superheated vapour. The model essentially assumes steady state operation of the power cycle. The possible unit time where this model can be applied is bounded by the time required by a system to come into steady state. The saturated vapour cycle yielded average error 4.20% with maximum error 9.25% and the superheated vapour cycle yielded average error 2.12% with maximum error 5.60%. The main advantage of the developed method is that it requires a minimum number of inputs: condenser (p,T), vaporizer (p,T), condenser heat load, turbine efficiency (overall), pump work and the extremum conditions of all the components. These inputs should represent typical operating conditions of a plant. The model can predict the appropriate plant performance depending on the system heat input (geothermal fluid flow in this case) and the heat sink temperature. As the method is based on basic thermodynamics rather than empirical or semi-empirical approaches, this method is widely applicable. The main focus of this work is on the ORC but the developed method is applicable to any closed Rankine cycle. In addition, application of the developed iterative method to predict plant performance based on mean yearly weather data is also discussed in the thesis. Water-augmented cooling system and optimization of plant operating point parameters have been proposed as adaptive measures to improve short term performance. Developed iterative method has been used for the short term performance analysis. The water-augmented cooling system is specifically suitable to mitigate the reduced power output during the summer. The simulated average gain in power during the summer (Jan, Feb, Nov and Dec) of an ORC of Mokai 1 geothermal power plant by incorporating a water-augmented cooling system was 2.3% and the average gain for the whole year was 1.6% based on the weather data of Taupo for the year 2005. A cost benefit analysis showed that water-augmented cooling system is more economical compared to other alternative renewable energies considered to meet summer peak demand. From the green house gas emissions perspective, water-augmented cooling is a better option than the gas fired peaking plants. Adaptive approach for short term performance improvement by optimizing operating point parameters of an air-cooled binary cycle has huge potential with possible maximum improvement in power output by about 50%. The optimization takes in to account the effects of the geothermal resource characteristics and the weather conditions. The optimization is achieved by manipulating cycle mass flow rate and vaporizer equilibrium condition. Further study on the optimizing operating points to achieve improved short term performance has been recommended for future work.

O revestimento de argamassa de fachada é utilizado em praticamente todos os edifícios residenciais;assim, sua importância é caracterizada tanto pelo uso intenso, quanto por desempenhar importantes funções estéticas e de proteção do edifício, além de representar importante parcela do custo direto de construção e de manutenção das fachadas. O presente trabalho busca caracterizar, analisar e propor melhorias ao processo de produção dos revestimentos de argamassa de fachada de edifícios, particularmente quanto às etapas de projeto, execução e controle, através de levantamentos realizados em quatro obras de importantes empresas de construção na cidade de Santos. A metodologia utilizada consistiu em revisão bibliográfica, e posterior aplicação dos conceitos levantados nos estudos de caso. Com base neste estudo, foi possível identificar as condições locais de produção e os principais problemas enfrentados ao longo do processo, tendo sido possível à elaboração de sugestões de melhoria ao processo analisado. Além disso, espera-se que se possa contribuir também para a disseminação de ações de racionalização do processo de produção dos revestimentos de argamassa de fachada de edifícios; e, por conseqüência, contribuir para diminuir os problemas patológicos e os custos de produção das empresas construtoras. / The façade mortar covering is used in practically all residential buildings; thus, its importance is characterized by its intense use and also for playing important esthetic functions in building protection. Besides the fact, that it represents an important parcel of the direct cost of construction and façade\'s maintenance. The present work searches to characterize, analyze and consider improvements in the process of production of mortar covering, particularly related to each stage of the project, execution and control by surveys carried through four construction sites of important construction companies in the city of Santos. The methodology used consisted of bibliographical revision, and posterior application of the concepts researched in the case studies. Based on this study, it was possible to identify local conditions of production and the main problems faced throughout the process, having been possible to elaborate suggestions of improvement to the analyzed process. Moreover, it is expected that it can also contribute to the dissemination of façade\'s production management. Consequently, contributing to diminish the pathological problems and lowering the cost of production for contractors.

Submitted by Nara Lays Domingues Viana Oliveira (naradv) on 2015-06-12T22:36:19Z No. of bitstreams: 1 000006AB.pdf: 9859828 bytes, checksum: 7298da927fa0f798beed1d1cb69fcb2a (MD5) / Made available in DSpace on 2015-06-12T22:36:19Z (GMT). No. of bitstreams: 1 000006AB.pdf: 9859828 bytes, checksum: 7298da927fa0f798beed1d1cb69fcb2a (MD5) Previous issue date: 2012 / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Neste trabalho, foi realizada a simulação do ciclo térmico da Usina Termoelétrica São Jerônimo – UTSJ. A Usina, muito antiga, possui caldeira do tipo grelha. Na mesma Usina foi instalada uma caldeira experimental de leito fluidizado, para funcionar em paralelo com a existente. O trabalho é iniciado com a modelagem de um ciclo de Rankine simples e segue evoluindo até se estabelecer a configuração mais adequada e representativa na tarefa de simular o modo de trabalho da Usina Termelétrica São Jerônimo – UTSJ. Desta forma, foram adotadas as considerações mais convencionais na prática de projeto de centrais termelétricas cujos sistemas térmicos baseiam-se no ciclo de Rankine. As simulações, que se caracterizam pela resolução simultânea das equações que modelam o ciclo e seus componentes, foram efetuadas através de programa IPSE-pro®. As simulações foram aplicadas para a obtenção dos resultados mais importantes na análise de sistemas térmicos, tais como rendimento térmico do ciclo, potência, vazões mássicas do sistema, calor trocado no gerador de vapor e no condensador, entre outros. Por fim, com objetivo de melhorar o rendimento térmico da planta, são apresentadas algumas alternativas ao sistema atual, tais como o aumento de eficiência da caldeira mediante substituição ou a adição de uma caldeira em paralelo à original. / In this work was made the simulation of the thermal cycle of São Jerônimo - UTSJ thermal power plant. The power plant, very old, has a grate boiler. In the same power plant was installed an experimental fluidized bed boiler, workingin parallel with the existing one. The work starts with the modeling of a simple Rankine cycle and evolves up to establish the most suitable and representative configuration to simulate the mode the work of São Jerônimo –UTSJ thermal power plant. Therefore, in this work it was adopted the more conventional considerations in the design practice for thermal power plants whose systems are based on the Rankine cycle. The simulations, which are characterized by the simultaneous solving of equations that model the cycle and its components, were made through the IPSE-pro® software. The simulations were applied to obtain the main results on the analysis of thermal systems such as, thermal efficiency of the cycle, power, system mass flow, heat exchanged in the steam generator and condenser, among others. Finally, in order to improve the thermal efficiency of the plant, some alternatives to the actual system were presented.

In this age of technology, people or the companies all over the world have started using the easyway to find information or to process a particular task selected or given. In this path, Informationsystems have gone a long way with day to day improvements and upgrades with everythingabout what it can be done to give the right access and right task to the users.The developers have gone to such an extent that nothing can be compromised in the developmentor in the implementation of Information systems, however in the practical scenario there aremany issues that are to be taken into consideration to develop an Information System and also inthe implementation of the same.Here, in this thesis we will try to bring out those factors where in the implementation ofInformation Systems can go wrong and what are to be considered in order for the IS to be usefulthan it has to be emphasising on user satisfaction and user acceptance / Program: Magisterutbildning i informatik

<p>Aim: This study investigates the degree of Six Sigma implementation in the aviation industry where it has been successful and is widely spread. Six Sigma is a quality measurement and improvement program and provides businesses with the tools to improve the capability of their business processes. The paper scrutinizes the possible consequences of implementing Six Sigma in a strictly controlled environment and how the defined success factors for implementation could be interpreted in this context. The concept of Six Sigma is examined with the objective to define recommendations for implementation at Saab Avitronics, a company within the aviation industry.</p><p>Method: The theoretical background presents what theories for Six Sigma successful implementation that are present and seeks to give the topic depth and perspective to establish a basis on which the analysis later is built on. Phases for implementation of improvement programs and success factors for Six Sigma are investigated. To establish the environment in which the theory is adapted the empirical part of the study presents a marketing audit and a SWOT analysis of Saab Avitronics. An internal survey is also performed to examine Saab Avitronics’ view on its own knowledge in the area of Six Sigma, improvement methodology, statistics, and the attitudes towards implementing a methodology based on Six Sigma. The analysis is performed by applying the theoretical background in the light of the reality of Saab Avitronics. The possibility of a successful implementation is discussed.</p><p>Result & Conclusions:Continuous improvements are a general prerequisite for survival and success and the study shows that this has also become a requirement imposed on companies within the aviation industry. Although special conditions apply to the aviation industry and Saab Avitronics there is nothing preventing from implementing the improvement concept in general, but special criteria have to be considered when choosing suitable projects. The study concludes with recommendations for Saab Avitronics on five phases for implementation; Plan, Pilot, Implement, Expand and Integrate, and main activities within these phases are defined. Finally the most important success factors for implementation at Saab Avitronics are defined and also how these should be interpreted for continuous improvement and future success.</p><p>Suggestions for future research: The investigation is limited to the aviation industry and to Saab Avitronics. Future research projects could further study the consequences at Saab Avitronics after implementation of Six Sigma, case studies of implementing best practise theories like these recommendations, and studying selection criteria for success factors.</p><p>Contribution of the thesis: The study contributes with recommendations to Saab Avitronics when implementing Six Sigma and also to the know-how and knows-what, to others than Saab Avitronics, when studying the same topic or when planning their own implementation of Six Sigma.</p>