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The aim of this thesis was to explore the use of genome-scale metabolic models to predict metabolic fluxes in plant tissues. Results from this thesis showed that the application of constraint-based modelling, namely flux balance analysis, to an Arabidopsis genome-scale metabolic model gave accurate predictions of metabolic fluxes in heterotrophic cell culture and in photosynthetic leaves. Two major factors important for the accuracy of model predictions were highlighted from the study: 1) the inclusion of energetic costs for transports and cellular maintenance in terms of ATP and NADPH; 2) consideration of the interactions between light and dark metabolism in modelling photosynthetic leaves. This study began with the construction of a well-curated and compartmented genome-scale metabolic model of Arabidopsis. Using the model, cellular maintenance costs in a heterotrophic cell culture under control and two stress conditions were estimated in terms of ATP and reductant usage. The results suggested that the cells were not stressed under hyperosmotic conditions. Comparisons between model predictions and experimentally estimated flux maps showed that the inclusion of transport and maintenance costs was important for obtaining accurate model flux predictions. To model leaf metabolism over a day-night cycle, a diel modelling framework was developed which took into account the interactions between light and dark metabolism. Numerous known features of metabolism in a C₃ leaf were predicted such as the nocturnal accumulation of citrate utilised for diurnal glutamate and glutamine synthesis and the operation of an incomplete TCA cycle during the day. Using the Arabidopsis genome-scale metabolic model and the diel modelling framework, the operation of the CAM cycle was predicted as a direct consequence of blocking the CO₂ exchange with the external air during the day to simulate closure of the stomata. Comparisons between model predictions of C₃ and various subtypes of CAM leaves suggested that photon and nitrogen use efficiencies are unlikely to be the driving forces for the evolution of CAM plants under the current atmospheric CO₂ concentration. Finally, the model was utilised to predict the changes in metabolic fluxes, in particular fluxes through various routes of alternative electron flow, in a C₃ leaf with varying light intensity, nitrogen availability and at different stages of leaf development. From the model flux predictions, it was shown that constraint-based modelling can be utilised to elucidate the distinct metabolic roles of enzymes in different subcellular compartments and the tissue-specific use of distinct forms of enzymes with different coenzyme specificities.

<p>Osnovni cilj ove doktorske disertacije bio je da se razvije novi automatizovani dijagnostiĉki model. Zatim da se praktiĉnom primenom tog modela (na konkretnom primeru automatizovane dijagnostike vitalnih komponenti tehniĉkih sistema u realnim pogonskim uslovima razliĉitih grana industrije) tehno-ekonomskom analizom potvrdi glavna hipoteza disertacije: &bdquo;Automatizovana dijagnostika tehniĉkih sistema u industriji (bazirana na kori&scaron;ćenju raĉunara i drugih savremenih informaciono-komunikacionih tehnologija) doprinosi porastu nivoau pouzdanosti i raspoloţivosti tih sistema, kao smanjenju ukupnih tro&scaron;kova i ekonomiĉnijem poslovanju preduzeća―.</p> / <p>The main objective of this doctoral thesis was to develop a new automated diagnostic model. Then with the practical usage of this model (in particular case of automated diagnostics vital components of technical systems in real operating conditions of different industries) with techno-economic analysis to confirm the main hypothesis of the dissertation: ―Automated diagnostics of technical systems in the industry (based on the use of computers and other modern information and communication technologies) contributes to the increase levels of reliability and availability of these systems, as well as the reduction of total costs and more economical management of the company‖.</p>

The purpose of this thesis is to explore disruptions Swedish wind turbines onshore are exposed to, and to estimate their economic impacts on the operators. We want to investigate whether there is a need for a more developed service and maintenance market within the Swedish wind power market. This study focuses on wind power, a renewable energy source in an emerging market, which experiences exponential growth. Sweden is a minor actor in the wind power market with a production of around 2 TWh yearly. The government aims at a total production of 10TWh in 2015 and 20TWh in 2020, which equals an annual growth of 24%. However, we hypothesize that the Swedish wind power market is negatively affected by a service and maintenance market which is underdeveloped due to a lack of competition. This results in lengthy repair times and disproportionate costs for wind power operators. The study was carried out by conducting semi-structured qualitative interviews and by sending out a survey to approximately 300 wind power operators. Six interviewees were wind power operators and one interviewee was a representative from an independent service supplier. We have also analysed the current cost situation of operators with theories about maintenance costs and we have also carried out an industry analysis on the service and maintenance market, which was based on Porter’s structural industry analysis. After conducting a structural analysis of the service and maintenance market, we can conclude a lack of competition today as there is a dominance of the wind turbine manufacturers as the service supplier. Furthermore we can see that this lack of competition has negative effects on the efficiency of the service and maintenance provided. The results also stress a need for a more developed service and maintenance market. We have found that the profitability for the Swedish wind power operators is challenged if the service and maintenance market is not keeping pace and meeting the demands of the rapidly growing Swedish wind power market as a whole.

<p>The purpose of this thesis is to explore disruptions Swedish wind turbines onshore are exposed to, and to estimate their economic impacts on the operators. We want to investigate whether there is a need for a more developed service and maintenance market within the Swedish wind power market.</p><p>This study focuses on wind power, a renewable energy source in an emerging market, which experiences exponential growth. Sweden is a minor actor in the wind power market with a production of around 2 TWh yearly. The government aims at a total production of 10TWh in 2015 and 20TWh in 2020, which equals an annual growth of 24%. However, we hypothesize that the Swedish wind power market is negatively affected by a service and maintenance market which is underdeveloped due to a lack of competition. This results in lengthy repair times and disproportionate costs for wind power operators.</p><p>The study was carried out by conducting semi-structured qualitative interviews and by sending out a survey to approximately 300 wind power operators. Six interviewees were wind power operators and one interviewee was a representative from an independent service supplier. We have also analysed the current cost situation of operators with theories about maintenance costs and we have also carried out an industry analysis on the service and maintenance market, which was based on Porter’s structural industry analysis.</p><p>After conducting a structural analysis of the service and maintenance market, we can conclude a lack of competition today as there is a dominance of the wind turbine manufacturers as the service supplier. Furthermore we can see that this lack of competition has negative effects on the efficiency of the service and maintenance provided. The results also stress a need for a more developed service and maintenance market. We have found that the profitability for the Swedish wind power operators is challenged if the service and maintenance market is not keeping pace and meeting the demands of the rapidly growing Swedish wind power market as a whole.</p>

This article presents an econometric analysis of the maintenance costs for the Austrian railway system. The data contain observations of track maintenance costs from 1998 to 2000. Our analysis identifies the cost driving factors in order to determine estimates of marginal costs, as required by the infrastructure provision principles of the European Union. The analysis identifies the variables "track length" and "transported gross-tons" as the principal cost determinants. Furthermore, we observe that total costs as well as marginal costs increase with (i) a high proportion of the track occupied by train stations, (ii) the number of switches within a track, (iii) narrow bends, and (iv) considerable slopes. Moreover average as well as marginal costs for secondary lines are significantly higher than for main lines. (author's abstract) / Series: Department of Economics Working Paper Series

Svenska Kraftnät (Svk) is responsible for ensuring that Sweden has a safe, sustainable, and cost-effective transmission system for electricity. In an effort to reduce costs, Svk has participated in a study where it has been determined that there are mostly costs for common facilities that stand out cost-wise. The goal of this master thesis is to identify and assess what factors influence maintenance costs for the substations in the Swedish national grid for electricity. Response feature modeling was applied on longitudinal data for the substations (N=53) for years 2017-2020 to obtain individual intercepts with a common slope for further analysis. The factors included in the global model were based on Pearson correlation analysis and consultation with experts. Further attempts to improve upon the global model were made based on a stepwise variable selection made by comparing AIC, a log-transformation of the response, and by applying expert knowledge to attain a subset of predictors. all the resulting models were significant (P&lt;0.001) with the best model having an R2 of 0.8376. Predictions for a proposed substation was made for the first fifty years of lifespan. Predictors that were found significant in multiple models includes variables regarding substation size and age. Factors that were not significant in any model related to substation fence length and location amongst others. / Svenska kraftnät (Svk) är ansvariga för att försäkra att Sverige har ett säkert, hållbart och kostnadseffektivt transmissionsnät för elektricitet. I ett försök att minska kostnader deltog Svk i en studie där det fastslogs att det var främst kostnader för deras stamnnätsstationer som sticker ut kostnadsmässigt. Målet i den här uppsatsen är att identifiera och värdera faktorer som kan influera underhållskostnader för stamnätsstationerna i det Svenska stamnätet. Response feature modeling applicerades på longitudinell data (N=53) för åren 2017-2020. Individuella intercept skattades med en gemensam lutning för att användas vid vidare analys. Faktorerna som initialt inkluderades i den globala modellen var antingen inkluderade eller exkluderade genom en analys av Pearson korrelationer samt i rådfrågan med experter med sakkunskap. Vidare försök att förbättra den globala modellen gjordes genom att applicera en stegvis variable selection baserad på AIC. Samma process genomfördes efter en log-transformation av responsvariabeln. Slutligen skapades en ytterligare modell med en delmängd faktorer skapad av experter på Svk. Samtliga regressionsmodeller var signifikanta (P&lt;0.001) där den bästa modellen med avseende på R2 hade värdet 0.8376. Skattningar av framtida kostnader för en föreslagen stations första femtio år av dess livsspann gjordes. Faktorer som var signifikanta (P&lt;0.05) inkluderade variabler som beskrev stationsstorlek, ställverkstyp och stationsålder. Faktorer som inte var signifikanta i någon modell var bland annat faktorer med anknytning till geografiskt läge, staketlängd bland andra.

The efficiency of a best management practice (BMP) is defined simply as a measure of how well the practice or series of practices removes targeted pollutants. While this concept is relatively simple, mathematical attempts to quantify BMP efficiency are numerous and complex. Intuitively, the pollutant removal capability of a BMP should be fundamental to the BMP selection process. However, as evidenced by the absence of removal efficiency as an influential criterion in many BMP selection procedures, it is typically not at the forefront of the BMP selection and design process. Additionally, of particular interest to any developer or municipal agency is the financial impact of implementing a BMP. Not only does the implementation cost exist, but there are long-term maintenance costs associated with almost any BMP. Much like pollutant removal efficiency, implementation and maintenance costs seem as though they should be integral considerations in the BMP selection process. However, selection flow charts and matrices employed by many localities neglect these considerations. Among the categories of criteria to consider in selecting a BMP for a particular site or objective are site-specific characteristics; local, state, and federal ordinances; and implementation and long-term maintenance costs. A consideration such as long-term maintenance cost may manifest itself in a very subjective fashion during the selection process. For example, a BMPs cost may be of very limited interest to the reviewing locality, whereas cost may be the dominant selection criterion in the eyes of a developer. By contrast, the pollutant removal efficiency of a BMP may be necessarily prioritized in the selection process because of the required adherence to governing legislation. These are merely two possible criteria influencing selection. As more and more selection criteria are considered, the task of objectively and optimally selecting a BMP becomes increasingly complex. One mathematical approach for optimization in the face of multiple influential criteria is the Analytic Hierarchy Process. "The analytic hierarchy process (AHP) provides the objective mathematics to process the inescapably subjective and personal preferences of an individual or a group in making a decision" (Schmoldt, 2001, pg. 15). This paper details the development of two categories of comprehensive BMP selection matrices expressing long-term pollutant removal performance and annual maintenance and operations cost respectively. Additionally, the AHP is applied in multiple scenarios to demonstrate the optimized selection of a single BMP among multiple competing BMP alternatives. Pairwise rankings of competing BMP alternatives are founded on a detailed literature review of the most popular BMPs presently implemented throughout the United States. / Master of Science

Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2016-05-04T13:35:26Z No. of bitstreams: 1 arquivototal.pdf: 9161935 bytes, checksum: f754259723418e8bdd6374a6ee8b0b57 (MD5) / Made available in DSpace on 2016-05-04T13:35:27Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 9161935 bytes, checksum: f754259723418e8bdd6374a6ee8b0b57 (MD5) Previous issue date: 2015-08-28 / Passenger transport by bus has a public and notorious importance. A complex logistics chain that by integrating the urban fabric, affects the productivity of production systems due to their own productivity. In this segment, business and government are challenged to fund transport systems that can meet their needs and those of the society. Increased competitiveness, combined with political and social challenges strategically focuses the measures on maintenance costs, still few explored. Traditional ways of funding do not consider all the complexity around its accuracy. In the era of knowledge, the activities managed by projects are the most whose added value. The Activity Based Costs, as most accurate method, details the complexity of these costs. As management support maintenance costs, the exploratory research applies a model, specifically developed, integrating the GP and the ABC. In this sense it has been developed a chain of Generic Value in Public Transport, and a chain of Specific Maintenance value. Maintenance operations and support activities were mapped and grouped into macro activities (set of services / maintenance tasks). The search database, contained in materials services and requisition orders was collected via SQL (Structured Query Language) and documentary research, and validated by interviews. Evidence from a case study in two companies of João Pessoa / Brazil validate the model, presenting management indicators and details the actual maintenance costs throughout its value chain in three stages: cost of services, cost of vehicles and cost of operating lines. Thus, from the case study it can be said that the model, not being single, not definitive, It is effective in maintenance of public transport processes, the accuracy of the results. Even not allowing full generalizations, it is adhering to processes of transport maintenance to keep similar aspects. The application of modern costing methods such as ABC associated with the Project Management (GP), in fact it resulted in a management support maintenance costs in public passenger transport. / O transporte de passageiros por ônibus é de importância pública e notória. Uma complexa cadeia logística que ao integrar o tecido urbano, afeta a produtividade dos sistemas de produção em razão de sua própria produtividade. Nesse segmento, empresas e governo são desafiados a custear sistemas de transportes que possam atender as suas demandas e as da sociedade. O aumento da competividade, aliado a desafios políticos e sociais focam estrategicamente as ações em torno dos custos de manutenção, parcela ainda pouco explorada. As tradicionais formas de custeio não consideram toda a complexidade em torno de sua acurácia. Na era do conhecimento as atividades gerenciadas por projetos são as que mais adicionam valor. O Activity Based Costs como método mais acurado detalha a complexidade desses custos. Como suporte ao gerenciamento dos custos de manutenção, a pesquisa de natureza exploratória aplica um modelo, especificamente desenvolvido, integrando o GP e o ABC. Nesse sentido foram desenvolvidas uma Cadeia de Valor Genérica em Transporte Público e uma Específica de Manutenção. As operações de manutenção e as atividades de apoio foram mapeadas e agrupadas em macroatividades (conjunto de serviços/tarefas de manutenção). A base de dados da pesquisa, contidos em Ordens de Serviços e Requisição de Materiais foi coletada via SQL (Structured Query Language) e pesquisa documental e validada por entrevistas. Evidências a partir de um estudo de caso, em duas empresas de João Pessoa/Brasil validam o modelo que apresenta indicadores de gerenciamento e detalha os reais custos de manutenção ao longo de sua cadeia de valor em três estágios: custos dos serviços, custo dos veículos e custo das linhas operacionais. Logo, a partir do caso em estudo é possível afirmar que o modelo, não se constituindo único, nem definitivo, ressalva-se, é eficaz em processos de manutenção de transporte público pela acuracidade dos resultados. Mesmo não permitindo generalizações plenas, é aderente a processos de manutenções de transportes que mantenham semelhantes aspectos. A aplicação de métodos de custeios modernos como ABC associado à Gestão de Projetos, de fato resultou um suporte ao gerenciamento dos custos de manutenção em transporte público de passageiros.

This thesis deals with the design of a new maintenance system of a powder coating line at ABB. The theoretical part describes history of maintenance, used maintenance methods, and types of organizational structure. The practical part describes the current state of maintenance of the production line, analysis of the situation, and subsequently design of the new maintenance system.