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5236 Uppsatser om Power and control - Sida 1 av 350
Triac Driver Platform
In the electronic industrials, power control of AC motors is commonly used. For example power control of a washing machine motor, a vacuum cleaner motor or a coffee machine motor. The company Rejlers Ingenjörer AB has many projects where power control of AC motors is included. A prototype card for this task can save time and money for the company in the future and this is the reason for this thesis.The motors are power controlled by a TRIAC and control of the trigging pulses to the TRIAC. This card is modularly built and can easily be adapted for future projects where the power control of AC motors are included.The prototype card can be used as a subsystem in a larger electronics projects or as it is in lab environment for testing and evaluating new motors..
Frekvensreglering i det nordiska kraftsystemet
Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.
När rummen råder : En studie om skolan som disciplinerande rum
This study titled When the spaces dominate A study of the school as disciplinary rooms is a study where the emphasis is on quality and where the results are based on observations. The purpose of the research was to analyse rooms and other artefacts in the school as seen from Foucault?s analysis of power. He emphasised that power is expressed in human relationships. To understand how that power is used one can study the techniques adopted and resistance offered.
Less is More : Copyright som censur i Control Societies, och hur mindre censur tenderar att bli mer reglering
In what French philosopher Gilles Deleuze labelled Control Societies, mechanisms reminiscent of censorship ? that is, restriction of information that administrators of power wish to regulate the spreading of ? are present in the concept of copyright. This kind of censorship has the advantage of not being scrutinized by public eyes in the way that the work of institutionalized censorship agencies such as the Swedish Statens Biografbyrå was. It is not unlikely that expanded possibilities for punishing anyone who spreads copyrighted material will result in larger and larger areas that may not be accessed, as the avoiding of conflict and repressive actions will emphasize the behaviour to take detours around information that is deemed taboo and therefore suspicious and dangerous. The ACTA trade agreement is one proposed tool for such extended possibilities for punishment.This essay does not however claim that copyright and censorship are the same ? but rather that the institutional execution of power that was previously a matter of state censorship has a lot of similarities with current and prognosticated application of copyright laws by corporations.
Less is More : Copyright som censur i Control Societies, och hur mindre censur tenderar att bli mer reglering
In what French philosopher Gilles Deleuze labelled Control Societies, mechanisms reminiscent of censorship ? that is, restriction of information that administrators of power wish to regulate the spreading of ? are present in the concept of copyright. This kind of censorship has theadvantage of not being scrutinized by public eyes in the way that the work of institutionalized censorship agencies such as the Swedish Statens Biografbyrå was. It is not unlikely that expanded possibilities for punishing anyone who spreads copyrighted material will result in larger and larger areas that may not be accessed, as the avoiding of conflict and repressive actions will emphasize the behaviour to take detours around information that is deemed taboo and therefore suspicious and dangerous.The ACTA trade agreement is one proposed tool for such extended possibilities for punishment. This essay does not however claim that copyright and censorship are the same ? but rather that the institutional execution of power that was previously a matter of state censorship has a lot of similarities with current and prognosticated application of copyright laws by corporations.While claiming to protect the individual, the disciplinary power executed actually aims to protect the one executing it; the purpose of the power structure is to replicate itself..
Den som ger sig in i leken får leken tåla! : En studie om barns maktlekar
Our essay is about children's exercise of power, oppression or domination in games or when playing on school grounds with one and other. We thought it would be interesting to look into how children in preschool and up to the fifth grade use power acts respective power plays in leisure-time. During four days we visited two different after-school center and carried out observations of children during the school day and later inside the recreation centers during leisure activities. In order to analyze our empirical material in relation to power, we have used Magnus Hörnqvist (2012) interpretation of Michel Foucault's theory of power - Another Foucault. We have also used Åsa Bartholdsson (2008) thesis about The regular exercise of power regime ? about normality and power in school.
Vanmakt och motmakt i personliga assistenters relationer till brukare
The aim of this study was to examine the aspect of power in the relationship between the personal assistant and the disabled person he or she works with (the user). The study was based on interviews with five personal assistants who worked for private companies that provided personal assistance. Seven themes were identified and discussed. These were: the users amount of control over the assistance given, the workplace environment, the working conditions, the organization of personal assistance by private companies, the assistants recourses and usage of power and the users participation in chores. To analyze these themes I used Foucault's theory of power and the perspective of Human Resource.
Modellbaserad drivlinereglering
A cars powertrain consists of everything that is needed for its propulsion. The components in the driveline that transfer the power from the engine to the driven wheels are not absolutely stiff, hence they will wind up due to the torque and act as torsion springs. If you suddenly demand a bigger torque by stepping on the accelerator pedal, a so called tip in manoeuvre, and that torque is acquired from the engine as quickly as possible, the driveline will not be able to transfer that fast torque change due to its weakness and as a result it will start to oscillate. These oscillations will be transferred to the driven wheels and make the car to accelerate jerkily which will be experienced as uncomfortable by the passengers. Furthermore, there is a backlash in the driveline that will make the weakness in the driveline even more excited than it should have been if the backlash did not existed.To avoid too big problems with these oscillations there is a control system that controls the demanded torque.
Tsunamikatastrofens politiska efterspel - En fallstudie av ansvarsutkrävandets värde i demokratin
The Swedish society woke up Boxing Day 2004 to the greatest disaster in modern times. As a result of a strong earthquake in the Indian Ocean tsunamis occurred that devastated resorts where thousands of Swedes were. In the disasters tracks were uncovered government paralysis and shortcomings of the systems control. The purpose of this study is to examine the capacity and means to demand accountability of politicians and officials of the Swedish political system. Extensive studies and the report from the commission of disasters will form the basis for the study.
Automatisering av spraytorkningsprocess
ABB Surge Arrestors in Ludvika have for a long time had a problem to keep the moisture at a steady state in the production of their ZnO-powder, that is used to produce varistors.Some black-box models of the spray drying process have been designed and evaluated to find a solution for the problem. After evaluating the collected data it has been found that variations in the supply voltage causes control difficulties for the operator. A cascade control system was designed, consisting of three PI control loops designed with lambda tuning. The disturbance in the supply voltagewas used as a feed forward in the control system.At the end of the project the control system was installed, and tests were made to verify the functionality of the regulator. It was shown that most of the variations in the moisture of the powder could be eliminated using small resources, through purchase of a process controller and four power meters.
Modellering av reserv- och nödkraftsystem i JAS 39 Gripen
Simulation is a vital tool during development of JAS 39 Gripen, since money and time can be saved.The Auxiliary and Emergency Power System, AEPS, is a subsystem of the secondary power system in Gripen. It has the function of providing the aircraft with electrical and hydraulical power before activation and after deactivation of the main engine. The system also functions as backup in case of a safety critical problem in the main power supply system. The system basically consists of a control unit and an auxiliary gearbox. The gearbox is driven by an air turbine.
Hjälpande makt : En studie om uppdraget som god man
This study illustrates how the power relation between the trustee and principals are experienced and maintained in proportion to the missions design. The main focus lies on understanding of how trustee perceives and applies the mission`s cornerstones and how power can be expressed in the relationship between trustees and principals. Nine semi-structured interviews were conducted with trustees whose principals were mentally disabled. The interviews were then analyzed with the support of Foucault's concept of discipline, knowledge, control, surveillance and reward/punishment and Tilly's theory of persistent inequality We have obtained an understanding of the complexity of the assignment regarding the mission`s cornerstones who goes into every other, and all respondents agreed that the cornerstones should be considered as a whole. We concluded that the trustee on the basis of the mission's design possesses a power that is necessary and important to have regarding the relation to his principal and its social network.
Hantering av skadade styrstavar
The thesis was performed at Forsmarks Kraftgrupp AB in the department ofmechanical engineering, FTCM. Forsmark nuclear power plant has had problems with cracks in some of the controlrods which are placed in the reactor at Forsmark 3. To investigate the cause of this,material samples were taken from five of the damaged control rods. This sampling ofthe rods resulted too short rods to be transported in the shipping container to theinterim storage facility for used nuclear fuel in Oskarshamn. Control rods are crucial components in a nuclear reactor, regulating the reactoreffect by blocking or unblocking fuel rods. Control rods which have been in thereactor are always handled under water in order to protect against the radiation theyemit. The task was to design a control rod adapter that extends the control rod sotransport can be performed from Forsmark. The goal of the work was a complete setof blueprints so the control rod adapter can be manufactured and mounted on theshort control rods and then be transported to the interim storage facility. The work began with mapping of how control rods normally being handled from thereactor to the interim storage facility.
Styrelsens användning av styrmedel -en jämförelse mellan entreprenöriella och icke-entreprenöriella företag
Management control systems are a popular area of research and a lot of new research has been done over the past years. This development has been looking into new situations and circumstances, and interdisciplinary studies are being made to further understand the connection between different fields of study. A new field of study that has grown significantly over the past few years is the connection between management control systems and entrepreneurship. Leading researchers have proposed a number of questions for further research and one of them is the board of directors? use of management control systems in entrepreneurial firms.The purpose of this study was to examine the differences and similarities in the board of directors? use of management control systems between entrepreneurial and non-entrepreneurial firms.The study was conducted as a deductive qualitative study through interviews with respondents from entrepreneurial and non-entrepreneurial firms.
Konstruktion av UPS-modul
This master thesis describes the development of an UPS module. UPS is an acronym for Uninterruptable Power Supply. The UPS module has been developed at the company AerotechTelub AB. The UPS module delivers the necessary voltage and current in case of a power interrupt. If a power interrupt occur, the computer system has one to three minutes available to store data and shut down correctly.