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235 Uppsatser om Characteristic impedance - Sida 3 av 16
Undersökning av vissa beläggningars påverkan på antenners effektivitet i tågmiljö
For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.
VSM och 16 förluster
With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.
Sound Fence
To fence in pastures for sheep today is a major cost, especially because of the time required when using current methods. What takes most time is starting to fence off a new area, but to maintain a fence is also a continuous effort. The main function is to keep the sheep at the field.! !By interviewing and observing sheep farmers on how they work with fence today and what their problems was, I got a better understanding of the problem. Also looking at a number of other things like the context, statistics on sheep farming, laws and competition mapping gave a wider image. But the most important part in my research occurred when I talked to experts about sheep behavior.
Sambandet mellan kontroll i arbetet, psykologisk flexibilitet och välmående
The work organization variable control and the individual characteristic psychological flexibility are two concepts that affect employees? well-being at work.This cross-sectional study examined the extent to which these variables correlated with burnout, mental health and job satisfaction among homecare workers in Sweden (N=68). As hypothesized, results showed that both control and psychological flexibility were associated with burnout and job satisfaction. Findings also showed that psychological flexibility was associated with mental health. Moreover, the results indicated that there is an interaction effect between control and psychological flexibility in relation to these variables.
Den sardoniska rättskiparen som våldsprincip : En etisk karaktärsstudie av domare Holden i Cormac McCarthys Blodets meridian
This paper analyses the character judge Holden in Cormac McCarthys novel Blood Meridian through an ethical perspective. The author uses several methods to analyze the character ethically, such as the western-genre, McCarthys authorship, evil as an ethical term and Friedrich Nietzsche's theory the Übermensch. The author then uses a selective group of scenes and chapters from the novel to highlighting the distinctive ethical characteristic of judge Holden. The author finds judge Holden to be the very principle of violence and blood shedding, defending and distributing these principles in his words and his actions throughout the novel. Triumphantly proclaiming his victory, judge Holden embodies the principle that whoever has the power to perform any action has then the moral right to do so.
Binär matchning av bilder med hjälp av vektorer från deneuklidiska avståndstransformen
This thesis shows the result from investigations of methods that use distance vectors when matching pictures. The distance vectors are available in a distance map made by the Euclidean Distance Transform. The investigated methods use the two characteristic features of the distance vector when matching pictures, length and direction. The length of the vector is used to calculate a value of how good a match is and the direction of the vector is used to predict a transformation to get a better match. The results shows that the number of calculation steps that are used during a search can be reduced compared to matching methods that only uses the distance during the matching..
Vad är ?rätt? gjutkvalitet? Hur uppnås det?
Ever since ABB has begun diecasting their rotors instead of permanent mold casting it,variation in the quality of the cast has arisen. Diecasting is performed in three differentmachines, M1, M2, M3 with 400, 660 respectively 800 tons of die locking pressures.The aim of this thesis is to answer the following questions:What is the ?right? cast quality? How is the right quality achieved?For sizes 160-180 solutions will be proposed that consider eccentricity between thelaminate and the short circuit ring as well as elimination of the thin Al film that appearson the outer periphery of the rotors.Through considering the statistic material the most often diverging rotor type has beenidentified and one of the actual rotors has been sent to a laboratory to be analyzed inorder to establish the current defects. The result of the analysis shows that there areplenty of gas- and oxide-porosity.It has been proved that every time the dies temperature decreased below 120°C thecontent of gas porosity increased. It is due to rapid solidification of metal that flowsthrough the ?cold? laminate.It has confirmed that enhanced porosity in squirrel cage causes high impedance in therotors.
Simulering av vindkraftverk och närliggande elnät vid Risholmen i Göteborg i SimPowerSystems
With background in the rapidly growing need to find solutions for sustainable energy production and the increasing interest for wind power, this report was written. With take-off point from the wind power plant Big Glenn, which has been built in the harbour of Gothenburg, a model of the adjacent power grid has been created in Simulink/SimPowerSystems. Parameters for the power grid and its components has been provided by Göteborg Energi Nät, that has also been the supplier of measurement data of produced power, the power need from loads in the vicinity, voltage levels, current values and also the variation of power factor at the wind power plant.The SimPowerSystems model has been used to perform simulations of power flow in the grid. These simulated values have then been compared to the measured values to verify the functionality of the model. Further, the model has been used to perform simulations of a grid fault, which causes a voltage drop.
?I don?t give a shit about fashion. I?m a man? : En kvalitativ undersökning om maskuliniteter och mansideal i Magazin Café
The aim of this study was to identify what kind of masculinity is shown in 54 articles of the Swedish lifestyle magazine Magazine Café of 1993 and 2008, and in which way this masculinity may be different from eachother.The study included four magazine issues of each year with analysis focus on main articles and abolishment of reviews and press items. The method was semiotic analysis with focus on manly characteristics and stereotypes. The result showed that the normative man pictured in Magazine Café in 1993 was a man?s-man interested in manly characteristic business as sports, outdoor adventures and women. Fifteen years later not much has changed. The manly characteristics are the same but they have been complemented with a man-by-man accepted and homosexually inspired vain..
Avancerad flöjtteknik. Hur kroppen befäster finmotoriska färdigheter
The aim with this essay is to look into what literature has been published in 2006 and 2007 for boys between the ages of twelve and sixteen in order to analyse six of the titles. Our two main questions are as follows:?How is the teenage boy depicted in six of these books? - To what extent is the teenage boy depicted in a gender stereotypical way?.We chose the titles for analysis based on our mapping of the published literature and took into account the authors? gender and age as well as the main themes of the books. As theoretical base for our analysis we used Marias Nikolajeva?s table of gender stereotypes in literature.
Optimering av informationsinsamlingvid prototyptillverkning
This report discusses a method to detect divers in harbour environments usingpassive acoustic detection. The goal was to achieve as high detection as possiblewithout having too high false alarm rate. A short execution time was also desirable.By using the characteristic of an inhalation a band-pass filter was applied to the signalto improve the signal to noise ratio. After the filtering an energy estimation of thesignal was made. This energy estimation was later used in a frequency analysis, whichcould tell us if there were enough energy in the frequencies that correspond to adivers breathing frequency.
Signalanalys med ATLAS
On Ericsson Ltd in Borås a wireless communication system called MINI-LINK? is produced. In order to sell their product with the best possible quality guaranty, there is a signal processing circuit called ATLAS implemented in the system. This circuit would eventually be useful in the production and for the repairs of the radio units. Our commission was to examine the possibility for this use.
Pojkar i litteraturen och litteratur för pojkar : Analys av sex moderna ungdomsböcker för pojkar
The aim with this essay is to look into what literature has been published in 2006 and 2007 for boys between the ages of twelve and sixteen in order to analyse six of the titles. Our two main questions are as follows:?How is the teenage boy depicted in six of these books? - To what extent is the teenage boy depicted in a gender stereotypical way?.We chose the titles for analysis based on our mapping of the published literature and took into account the authors? gender and age as well as the main themes of the books. As theoretical base for our analysis we used Marias Nikolajeva?s table of gender stereotypes in literature.
Nätet spinns vidare : Hur används Internet i ungdomsromanen?
The essay is a text centred study of ten Young Adult Novels, in which Internet plays an essential part. The structure is put into light out of used narrative techniques of how to create stories and its construction elements. I compare the ten Young Adult novels to each other. My aim is to analyze the functions of the Internet motive in the chosen novels, using different approaches, and enlighten it with concerns to the new phenomenon that Internet is in society. Consequently the essay will also have a mimetic touch to it.The ten novels that I base the analysis on are written of both med and women and have both male and female as main fictive persons, and are from different parts of the world.
Att bli framgångsrik musikartist : De karaktäristiska dragen i marknadsföringen av artister
The research this report is based on aims to find out the characteristic features of the marketing tools that are essential for a music artist, and define a successful artist. The thesis arises and discusses how different medias can have an affect on an artists career and on his/hers achievement. To bee seen in the right medias can have an important influence on their career. To be able to answer our aim we have interviewed people who have a solid knowledge about music business, we have also used a qualitative method. The outcome of the research is that there are some indications that show important factors which are essential when it comes to marketing artists.