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..

Research in solar energy is taking big steps in both solar heating and solar electricity. It´s not only the technologies alone, but also the combination of both solar electricity and solar heating which is what is called a solar hybrid. The idea of a solar hybrid is that a solar cells efficiency decrease with increased temperature and can with help from a solar collector be cooled and the heat can be utilized. This thesis report compares heat production and electricity production with respect of, in first hand, a solar hybrids geometry in the cooler. The theory chapter describes solar heating and how different solar cell technologies work and their environmental impact at the production and how compatible these technologies are for the solar hybrid.

An important process for grid companies in order to reduce power losses in electricity distribution grids is to figure out where and how they appear. This report describes the factors that cause power losses in low voltage distribution grids and methods for how they could be measured and analyzed. Measurement data for consumed and injected energy were collected for twelve low voltage distribution grids owned by Gävle Energi AB in order to analyze the size of the power losses and how the measurement uncertainty affects the collected data. Then models of three of the grids were created in MATLAB in order to analyze the data and the power losses were calculated to be compared to the collected data. Curve fitting were also used as a method in order to analyze the power losses from collected data.The results show that the losses in the studied grids are low.

The supply of uninterruptible power can be applied to many areas wherecontinuous operation is highly prioritized.The application of uninterruptible power for motor operation is facilitatedusing a frequency converter. Direct current operated frequency converters canbe applied directly to the power reserve which removes the need for additionalpower-converting.Batteries have long constituted the power reserve but advancements inthe development of ultracapacitors have created a viable substitution. Ultra-capacitors have high energy storing capabilities and can be applied to highpower applications.Maxwell is a leading manufacturing company of ultracapacitors and pro-vide different modules with built-in solutions for voltage balancing. Unevenvoltages between series-connected capacitors is a phenomenon caused by vary-ing capacitance. A configuration containing Maxwell?s 56V module is createdand constitutes the power reserve in the simulations.The discharge simulation shows a significant current that could damagethe system.

Violence against teachers in Swedish schools, according to recent reports has increased and there have been many studies to investigate the situation for teachers. The surveys show that teachers are especially vulnerable to students. This study aims to examine the relationship between a number of teachers and their students to study the power relations that exist in the classroom. This is to see what violence is an expression of and also how violence is perceived by the teachers. The issues that are central in this study are:What is the importance of dialogue in the relationship between these teachers and their students?Is there power relations between teachers and their students?What is the violence against teachers and expression of?Is there any connection between dialogue, power relations and violence?The theories of the materials in this study was analyzed using power relations theories of the historian of ideas Michel Foucault and Philosophy Doctor Anders Persson, who to some extent has his theoretical basis in Foucault?s power relations.

The purpose of this thesis is to identify power structures and instruments of power within the Jehovah?s witnesses and investigate how they affect the baptized youths baptized within the organization. The material consists of qualitative in-depth interviews and is analyzed with Foucault's theories of power. The results show that the participants have a very strict relationship to the rules of the congregation and also that they take great care in observing these rules carefully. It becomes evident that young members are exposed to disciplinary measures from the organization.

The purpose with the report is to show that it is possible to design a class-D amplifier, using a programmable FPGA mounted on a developing card from Xess and a H-bridge. The FPGA was programmed in VHDL which is the language the software from Xilinx use to implement a logical function into the FPGA The logical function corresponds to a modeling of the music signal and the modeling can be described as a comparator which compare the music signal with a triangle wave and as a out signal produce a pulse width modulated (PWM) signal. The report is also a review and evaluating of two different modulating technologies, AD- modeling and BD-modeling. A detailed part about how the H-bridge was designed and how it works. The result of this project is a working audio amplifier to a significant lower price than the products in todays market..

According to many scholars America's soft power is in decline, a power resource whose importance has been increasing in world politics. This makes it interesting to examine if there is a difference between how Democratic and Republican administrations wield their soft power.This thesis is a hypothesis-testing study and the purpose is to test the hypothesis that Democratic administrations, to a greater extent than Republican, can create, utilize and defend soft power. My thesis is based on Joseph Nye's theory of soft power and the focus of this study is the aspects of the foreign policy resources. In order to measure this concept I have made my own operationalization where five different indicators serve as my guidance. I use the method of least likely-cases to select and motivate the administrations being tested, which gives me a comparative study of the Democratic administrations of Lyndon Johnson and Bill Clinton and the Republican administration of George H.

AbstractThis study examines the technologies appropriate in developing back-and solutions for search-driven user interfaces of e-commerce sites. The study is based on existing research in search-driven user interfaces of e-commerce sites from a design point of view, but instead the focus of this study lies within a back-end perspective. This choice of focus is a result of the gap that was encountered within research and other literature when it comes to general advice in how e-commerce sites best should build back-end solutions to support search driven user interfaces. The technologies that have been examined and compared are traditional relational databse management systems (RDMS) and the newer so called No-SQL database management systems, and also traditional search engines and the newer variant s of search engines. The study concludes that in some cases it is appropriate to combine traditional and newer technologies when it comes to databases, while the comparison of search engines indicates that there are some newer search en gines that have the ability to meet more of the needs that can be identified on the back-end solutions.Primary data consists of interviews made ?face to face? with experts on the subject and questionnaires addressed to selected e-commerce companies via e-mail.

Some people do not have the opportunity to visit a physical exhibition because of limited time or long travelling distances, it is here the need for a web-based exhibition arises.This dissertation describes the development of an interactive web-site representing a part of a physical exhibition of over 200 interviews on different peoples immigration to inner Scandinavia. The interviews contain text, audio clip, pictures and video clip.The website contains modern programming technologies such as HTML5, ASP.NET MVC3, SQL, JavaScript and jQuery.A cover of the technologies used and how the project has been designed and implemented is explained in the dissertation. In the end of the dissertation we discuss about how the result of the project follows the goals we set up in the start phase. The result of this project is an interactive and easy to use web-site showing a part of the physical exhibition online. An easy administration to insert new information and edit existing without any major computer knowledge..

This thesis project explores technologies that enable people to experience the world through animals' senses in order to spark interest in and awareness about the marine environment and its inhabitants. The project is carried out as part of a planned ocean themed science center. The purpose is to explore how a greater understanding of the marine environment can be achieved using interactive technologies. The thesis is based on a theoretical framework consisting of academic works on experience, learning in a museum context and sensory perception. Our proposed designs are a series of, primarily, wearable devices that translate sensory experiences and principles from the marine world to humans.

The purpose of this study is to investigate how much of the estimated annual electric energy production from Swedish wind power that actually was produced, as well as the history of this agreement over time. The aim is to also examine if there are properties that have caused some group of wind power plants to produce more or less, compared to their estimated production. Operational data on wind turbines collected by the Swedish Energy Agency was analyzed. A survey was made among owners of wind power plants with a nominal power of at least 2 MW. Two different methods for normal year correction of production data were used and compared.

This study is an institutional analysis of the firm both as it is theoretically conceptualized and how it takes shape and changes. The role of power relations between manage¬ment and employees is especially examined with the aim of evaluating pos¬sible connections between the firm as an institution and power relations within it. Based on a comparison of two cases (two selected periods of the same organization) it asks ?How closely does each case match the conceptual characteristics of the firm??; ?What are the power relations between management and employees in each case??; and finally ?What factors account for the resulting differences??. It is found that there is a negative correlation between employee power and proximity to the firm as a concept.

Currently there is a controversial debate about that we must reduce our impact on the global warming; therefore both the Government and the local authorities have invested heavily in developing renewable energy in Sweden. The major development on the wind power market can be seen as a result of both the technological development and also on the decision that the Government took in 1996, which opened up the wind power market for private parties.This paper has aimed to examine the types of financial innovations that have arisen from the investments and financing of wind power on Gotland, and what these innovations can contribute to the future development of wind power.The problems that this thesis is based on is; what kind of financial innovations have occurred within investment and financing of wind power? How can these innovations contribute to the continued development of wind power on Gotland? The conclusion of this study shows that respondents and participants have defined a number of financial innovations that have emerged. Where some of the innovations only can be seen as incremental since they are based on continuous improvements, while others can be seen as radical as they are completely new for the context in which they operate. The study has also shown that Gotland has a great potential to produce more renewable electricity, but the development is dependent on the new power lines being built, in order to export electricity to the mainland..

The power system modelled in this thesis work has been developed for simulationwhen e.g. the production in some part of the power system is changed. The powersystem has been modelled according to the swing mass of the system, the frequencydependency of the load and the turbine governor. The model determines the systemfrequency, the period of regulation and the power exchange between the differentsubsystems in the Nordic synchronized system.In this model the system frequency is assumed to be the same in all different parts ofthe power system and the voltage conditions in the power system are neglected. Forthat reason power swings does not occur between different subsystems in the powersystem, which usually occur as a result of the swinging connection between thetransmissions line.