This thesis deals with application of optimisation methods based on linear and mixed-integer linear programming to various problems in the power sector related to electricity production. The thesis goal is to test the applicability of such methods to formulating and solving various instances from the class of real-world electricity production problems, and to find the advantages and disadvantages associated with using these methods. Introductory chapters describe the main characteristics of power markets, including the historical and regulatory context. Fundamental properties of power markets on both demand and supply side are also described, both from a real-world and a modelling point of view. Benefits of optimisation and modelling are discussed, in particular the solution feasibility and optimality as well as insights gained from sensitivity analysis which is often difficult to replicate with the original system. In the core of the thesis, optimisation techniques are applied to three case studies, each of which deals with a specific problem arising during electricity production. In the first problem, the profit of gas-fired power plant in Slovakia from selling power on the day-ahead market is maximised. The model is set up using both technical and commercial constraints. The second problem deals with the problem of representing a two-dimensional production function which primarily arises for a hydro generator with large variations in the level of its reservoir. Several representations of the original function using piecewise linear subsets are presented, compared, and characterised by their computational intensity both theoretically and practically. In the third problem, the prices on the German day-ahead market in 2011 are modelled. Contrary to the previous two models, the model does not capture an optimisation problem faced by a single producer, but incorporates a large subset of the whole market instead. Consequently the model is formed out of generic constraints relevant to all power plants whose parameters are estimated. By combining information about the aggregate availability of power plants with the estimated efficiencies a full supply curve for each day is created. Different scenarios are analysed to test the impact of uncertain inputs such as unknown or estimated constraints. The choice of the investigated problems stems from the attempt to cover electricity production problems from the point of view of multiple criteria. The three investigated electricity production problems span a broad range from the decisions of a single power plant to the modelling a power market as a whole. Formulations of the production function with different level of detail are presented ranging from a simple linear relationship to several bivariate function formulations. While each problem answers a specific question, they all illustrate the ease with which various electricity production problems can solved using optimisation methods based on linear and mixed-integer linear programming. This is mainly due to the ability of these methods to approximate even non-linear functions and constraints over non-convex domains and find global solutions in reasonable time. Moreover, models formulated with these methods allow sensitivity and scenario analyses to be carried out easily as is illustrated in each of the case studies.

Master thesis is dealing with the issue of condensate creation and removal from the Nesher Ramle steam turbine during start-up and steady state. At the beginning a preliminary calculation of heat balance and the turbine itself is done. It is followed by description and design of drainage system supplemented by calculation of the steam flow through the orifices. Steam flow calculation was done via S. D. Morris, Pavelek with Kalčík and Ambrož, all three methods were compared. The main goal is the theoretical calculation of the amount of condensate created during start-up which is influenced by its initial state from which it is started. Three default states are considered, cold, warm and hot. In the last chapter the comparison of theoretical calculation with the measured data on real turbine is done and it is supported by the evaluation of the data from the measurement of the steam turbine at steady state on maximum power and half power. From the steady state analysis, percentage of water flow to expander from the total amount of condensate formed in the turbine were obtained.

This master„s thesis elaborates with EC motors problematic. There are described essential features of brushless DC motors, their principles, construction and methods for rotor position detection. There are mentioned commonly used control algorithms of EC motors including theory of three-phase convertors. This thesis also contains a complex design of the universal convertor for EC motor and its practical implementation. Power parts losses calculation, heat-sink calculation and measurements at the convertor prototype are also described in this thesis.

The theme of this diploma work is to define of a business aim for a concrete small-sized enterprise and to transform it into a business plan. The first part is an entry to the sector of small and middle-sized enterprises; there are definitions of specific attributes of these enterprises, thein advantages and disadvantages, and their importance for an economy. In the sekond part is presented a ground of a theory for a business plan and SWOT analyse The next part is practical part of diplom work. In the practical part is suggested and work up the business plan of founding of small enterprises.

This master´s thesis „The role and benefits of Incentives in attracting FDI in CR“ is focused on the sphere of investment incentives used as an instrument of Czech goverment policy by decision making of foreign investors to enter and start busines in the Czech Republic. This thesis gives a picture on the specific factors, which play the greatest influence on decision if foreign companies will finally invest in CR. There are four studies by evaluating company´s business plan to show influence of investment grants on start-up costs of investment comparison to obtained incentives funds and the impact on the employment in certain regions force on goverment employment policy.

The diploma thesis deals with a creation of a business plan which is about to analyze current situation of technological startup with the aim to stabilize it and create suitable solutions for expansion. The thesis contains some topics specific to technological startups. It also contains complete business plan of chosen strategy for the expansion.

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El presente trabajo de investigación se realizó en la empresa Southern Perú Unidad Minera Cuajone y tuvo como finalidad minimizar los tiempos improductivos en el proceso de relevo del personal que opera equipos de carguío y acarreo en interior mina aplicando la metodología Six Sigma. El procedimiento metodológico aplicado en la mejora de la gestión de la productividad de la flota de carguío y transporte se basó en la aplicación de la metodología Six Sigma desde la recopilación y análisis de datos en gabinete y campo. En la etapa inicial de gabinete se recolectó los datos del sistema de gestión de flota JMineOps y se procedió a revalidar la información en campo y registrar los tiempos improductivos más significantes del cambio de turno, en la fase final de gabinete se analizó la información extraída del anterior y nuevo proceso del relevo de personal , y se realizó una evaluación de los tiempos entre actividades, del tonelaje de arranque en las distintas guardias ,ya que es un parámetro fundamental a incluir para poder evaluar cómo se ve afectada la productividad en la primera hora del turno ,ya que al inicio de guardia se pierde tonelaje a causa de las demoras operativas en el relevo del personal, además, se comparará la disponibilidad física y utilización de la flota de equipos de carguío y transporte. Según el análisis se obtuvo que las demoras más significativas de la operación fueron Espera en Bahía de transporte, Personal Rezagado, Charla de Seguridad y Revisión de Pantallas para asignación de equipos que significaron el 37% ,59%, 77% y 84% respectivamente de las demoras totales. Los resultados fueron favorables, se redujeron las demoras operativas presentes en la primera hora de cada turno. Lo que permitió cuantificar las toneladas que se dejó de mover por la duración de los retrasos sobre la primera hora de turno siendo 1062 toneladas de mineral y 3938 toneladas de desmonte aproximadamente por guardia. Se incrementó la producción de arranque en 2000 toneladas de mineral al día, lo cual equivale a ganancias diarias de 14,348 $ y 5,236,985$ al año. Adicionalmente, se optimizó y automatizó el inicio de las operaciones, por ende, se redujeron las demoras operativas en el relevo del personal y con ello se aumentó la disponibilidad física de la flota de Palas y volquetes en 2.5%, en 1.6% la utilización de las palas y en 1.4% la utilización de los volquetes. / The present research work was carried out at the Southern Peru Mining Unit Cuajone Company and its purpose was to minimize unproductive times in the process of the Shift Change that operates loading and hauling fleet inside the mine applying the Six Sigma methodology. The methodological procedure applied in the improvement of the productivity management of the loading and hauling fleet was based on the application of the Six Sigma methodology from the collection and analysis of data in the office and in the field. In the initial stage of the office the data from the JMineOps fleet management system was collected and the information was revalidated in the field with the most significant unproductive times of the shift change. In the final phase of the cabinet the information extracted from the previous and new process of the shift change was analyzed. The evaluation of the times between activities and starting tonnage in the different shifts was carried out since it is a fundamental parameter to include to be able to evaluate how productivity is affected in the first hour of the shift. According to the analysis, the most significant delays of the operation were Waiting in the transport bay, Iddle Personnel, Safety Talk and Screen Review for the assignment of equipment that meant 37%, 59%, 77% and 84% respectively of total delays. The results were favorable, the operational delays present in the first hour of each shift were reduced. This allowed to quantify the tons that were not moved due to the duration of the delays in the first hour of the shift, being 1062 tons of ore and 3938 tons of waste approximately per shift. The start-up production was increased by 2000 tons of ore per day, which is equivalent to daily earnings of $14,348 and $5,236,985 per year. In addition, the start-up of operations was optimized and automated, thereby reducing operational delays in personnel replacement and increasing the physical availability of the fleet of shovels and dump trucks by 2.5%, shovel utilization by 1.6% and dump truck utilization by 1.4%. / Tesis

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Det blir allt enklare att starta ett företag i Sverige, mycket tack vare de många startupplattformar som finns. Samtidigt överlever knappt hälften av alla startup längre än fem år. En viktig aspekt för att inte misslyckas som nystartat företag är att förstå sina kunder och sina användare och lansera produkten till rätt kundsegment, samtidigt som det kan vara kostsamma undersökningar som också förlänger den kritiska tiden innan företaget börjar generera inkomster. För att det ska bli lönsamt krävs det också att företagen förstår hur informationen som insamlas ska användas för att förbättra produkten. Det här arbetet undersöker hur och när startups väljer att involvera sina användare i produktutvecklingsprocessen. För att besvara arbetets frågeställningar har en litteraturstudie utförts, där bakgrunden till problematiseringen kartlagts. Därefter genomfördes en intervjustudie med fyra olika startups där syftet var att förstå hur arbetet med användarinvolveringen utfördes i praktiken. Samtliga företag som intervjuades hade genomgått ett program på, eller finansierats av någon startupplattform. Studien visade att startups ofta inte följer en linjär produktutvecklingsprocess, utan måste anpassa den efter de finansiella och strukturella förutsättningar som företaget har. Därför lämpar sig ofta andra iterativa metoder för företagen, där insatsen för varje förändring blir mindre. Det gäller också för användarinvolvering, där företagen dock strävar efter att involvera användaren så mycket som möjligt då det upplevs som en minskad osäkerhet. En kontinuerlig involvering av användare är dock sällan genomförbart för nystartade företag. Dessutom gör bristen på erfarenhet det svårt för företagen att strukturerat fastställa de viktigaste kraven och behoven från användarna. Sammanfattningsvis pekar studiens resultat på att en utmaning för startups är att applicera en linjär produktutvecklingsprocessen på grund av bristande struktur och startupfas. De strävar efter att förstå sina kunder och användare då konsensus råder om att detta leder till en lyckad lansering då osäkerheten minskar och produkterna förbättras. / Starting a business in Sweden is becoming easier, thanks in large part to the numerous startup platforms available. However, barely half of all startups survive beyond the first five years. A crucial aspect of avoiding failure as a new company is understanding one's customers and users and launching the product to the right customer segments. Yet, conducting costly surveys can also prolong the critical period before the company starts generating income. To make it profitable, companies also need to understand how the collected information should be used to improve the product. This study investigates how and when startups choose to involve their users in the product development process. To address the research questions, a literature review was conducted mapping out the background of the problem. Then an interview study was carried out with four different startups, aiming to understand how user involvement was implemented in practice. All interviewed companies had gone through a program on or were funded by a startup platform. The study revealed that startups often do not follow a conventional product development process but have to adapt it based on the company's financial and structural conditions. Insted, other iterative methods are often suitable for new companies, where the cost for each change is less significant. This also applies to user involvement, although companies strive to involve users as much as possible because it is perceived as reducing uncertainty. However, continuous user involvement is rarely possible for startups with limited budgets and time constraints. Moreover, the lack of experience makes it challenging for companies to systematically determine the most critical requirements and needs from users. In summary, the study's findings indicate that a challenge for startups is to apply a linear product development process due to a lack of structure and the startup phase. They strive to understand their customers and users, as there is a consensus that this leads to a successful launch by reducing uncertainty and improving products.