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2700 Uppsatser om Wind power - Sida 50 av 180

Alternativa dagvattenlösningar för nyexploateringsområden med avseende på substansflöden

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

Sabina Spielrein i verklighet och fiktion : Kvinnorepresentationer i centrum för en studie av pjäsen Namn: Spielrein Sabina

This thesis discusses how a historic woman is represented on stage today. The woman in mind is Sabina Spielrein, and she is portrayed in a play called: Name: Spielrein Sabina. She was born in the late 19th century and made a significant impact on the development in psycho-analysis. Since her letters, diaries and fragments was found 1977, and later on in 1982, nu-merous of people have been fascinated regarding her life, especially with her relation to Jung and Freud. One of my arguments is that there could be another story to tell, as she is living in a context when women were organized and struggled for their rights on many levels.

Uppvärmningens betydelse för hopphöjd och fem sekunders sprintprestation : En experimentell studie om hur anaerob prestation påverkas av uppvärmningsintensitet

Syfte och frågeställningarStudien genomfördes med syftet att specificera vilken intensitet och duration vid uppvärmning som är optimal för att få ut största möjliga effekt vid anaerob prestation i form av maximalt vertikalhopp och fem sekunders maximal cykelsprint. Studien byggde på tre frågeställningar: På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt vertikalhopp? På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt fem sekunders sprinttest? Vilken uppvärmning är optimal för maximal muskulär explosivitet?MetodDesignen var en kvantitativ experimentell studie som innefattade fyra fysiskt aktiva kvinnor med genomsnittsålder på 24 år. Testerna bestod av nio tillfällen där en slumpad uppvärmning på ergometercykel genomfördes varje gång. Därefter genomfördes tre vertikalhopp, så kallade counter movement jump, på en kraftplatta och tre fem-sekunders sprint (5sCST) på Monarks Peak Bike.

Bland ambassadörer och varumärken : En kvalitativ studie av svenska universitets kommunikationspolicydokument

The aim of this thesis is to investigate in what way Swedish universities regulates its internal and external communication by the use of policy documents. The purpose has led to three research questions: what scope of communication is given to the documents user, if the document is challenging or redefining the current means of power, and how questions regarding trademark is taken into consideration. In order to achieve the purpose a discourse analysis is used as both underlining theory and comprehensive method. The underlining theory is based around social constructionism, structuralism, poststructuralism and critical discourse analysis. The analysis have taken emphasis from Norman Faircloughs three-dimensional model in which the documents have been studied on three separate levels.

Hur påverkar en ökad andel solceller Umeå Energis elnät? : ? En utredning med fokus på spänningsvariationer och osymmetri inom landsbygds- och tätortsnät vid en- och trefasanslutning av solcellsanläggningar

A good power quality can be an important prerequisite to achieve a sustainable society. Scandinavia's electrical system is in many respects superior, and Sweden has a fossil free electricity generation at 97 % and a reliability of electricity distribution at 99.98 %. Meanwhile, the EU has an ambition to expand the electricity market in order to achieve a joint trading business across Europe. This cross-border market will result in a large proportion of fossil energy sources integrated into our electrical system, which also leads to an increased need for renewable electricity production in Sweden. One part of this development is to increase the share of renewable micro generation that is locally or regionally connected to the power grid.

MIMO kanalmodeler

The objective of this diploma work is to investigate a set of Multiple Input Multiple Output (MIMO) channel models compatible with the emerging IEEE 802.11n standard. This diploma work validates also advanced, innovative tools and wireless technologies that are necessary to facilitate wireless applications while maximizing spectral efficiency and throughput. MIMO channel models can be used to evaluate new Wireless Local Area Network (WLAN) proposals based on multiple antenna technologies. The purpose of this thesis is to investigate means of channel models and their implementation in different environments such as: Matlab, C++ and Advanced Design Systems (ADS). The investigation considers also a comparison between the channel models based on theoretical data and parameter setup to the channel models based on statistical characteristics obtained from measured data.

Varför agerar vi som vi gör? : aspekter som påverkar pedagogers agerande

Our essay starts with two self-experienced stories where we describe how we as pedagogues act when children do not behave as we wish. We examine the different perspectives that can influence us pedagogues to act as we do. Our narrative about Kevin, seven years old, shows how he is excluded from his school mates as they perceive him as disruptive. Also the narrative about Pelle six years old is about his dislike of an activity he is forced to attendag ainst his will.The study is based on a hermeneutical method where, through the interpretation of different perspectives, we discuss several aspects that affect us in our actions. The perspectives we have chosen to highlight are treatment of children, organization, power structures, communication and reflection.Our narratives differ from each other in the way that the recreation instructor Ulrika has no mandate over her situation on this particular day she helps as an extra support in a class atschool.

Samspelet mellan naturbaserade arbetssätt och specialpedagogik: En kritisk studie

AbstractThis essay aims to problematize and illuminate the connection between special-education and nature-based activities. With a theoretical ground that is based upon a sociocultural perspective I consider the information from the field. Through a qualitative and critical perspective I performed individual interviews with five pupils from the sixth school-year in the Swedish elementary-school. I also performed Focus-group interviews with two educators and three teachers in the same school-form. By a Hermeneutical working-method I have found out that the informants in my survey have a common experience that activities performed in nature has a positive effect on learning.

Symbolisk dekoration : En studie av Järnspiralen som symbol under yngre järnålder.

When the Iron spirals investigated in this paper saw the light again no one looked at them as nothing more than decoration. It was first during the 2011 excavation in Old Uppsala that the symbolism of the items no longer could be ignored. The spirals of Old Uppsala lay along the walls of the great hall, which stood upon one of the human constructed plateaus in the area. The hall had been burned down and then cleared of all lumber. Then the iron spirals had been placed in the positions and then everything was sealed with a layer of clay.A study of the artifact began with the purpose to contextualize and interpret the iron spiral.

Analys och dimensionering av robusta kilspårsförband

This master thesis comprises analysis and dimensioning of a keyed joint between a generator axis and a hub with aid from the FEM-software ANSYS Workbench 13.0.The generator axis is a part of a hydroelectric power station that generates electricity with a reactions turbine, a Kaplan turbine. The existing keyway consists of one parallel key with the width 90 mm and height 45 mm. Due to a planned increase of the power of the generated power with 32 % a design study was needed to see if the keyed joint would be suitable for the extra force. Because of the fact that the axis diameter is bigger than the standards covers/recommends a the keyway had to be re-dimensioned. In an earlier assignment from Skellefteå Kraft AB to Sweco Energuide the keyway was planned to be properly dimensioned, but no final solution was approved.During this master thesis a number of different numerical tests were made.

Den nya musikbranschen på AllEars.se : Det demokratiska mötet mellan skivbolag och artister på Internet

AbstractTitle: The New Type of Music Industry at AllEars.se (Den nya musikbranschen på AllEars.se)Number of pages: 49 (53 including enclosures)Author: Viktor BackemarTutor: Else NygrenCourse: Media och Communication Studies CPeriod: Fall 2007University: Division of Media and Communication, Department of Information Science, Uppsala University.Purpose: The purpose of this paper is to compare AllEars´ own view of the website AllEars.se to an observed view of the same site. The comparison is based on theories regarding the Internet in today?s society, convergence, communities and collective intelligence, interactivity and participation, and business in today?s society.Method: Since the paper has a purpose to compare two views of the same website there are two main methods in use. AllEars´ own view has been created via an interview with the company?s CEO, a press release that was released in connection with the launch of the website and texts found on the website.

Äga rum: Offentliga rum betraktade i ett politiskt perspektiv, fallet Pristina

In order to fully grasp the phenomena 'City' we must understand its political structure as an integrated part of its physical structure and vice versa. This thesis focuses on one crucial element of the City, the public space, and discusses it in relation to the public realm, or sphere, of the City. The aim is to see if it is possible to conceive public space as a spatial dimension of power, and if so, how to analyse this. With the help of the theoretical tool of two ideal types of the configuration of public space, "The city as civic public life" and "The city as authoritarian control" an empirical study is carried out on the case of Prishtina, capital of Kosovo.Conclusions made are that function and use of a city's public spaces can be understood in relation to changes in the political climate of the society. Furthermore, a void in the asset of concepts offered by the ideal types is found ? and therefore also need for new concepts to describe and understand a public space undergoing a dynamic transformation, as being a part of a city in political transition..

Möjligheten för solceller genom solcellskooperativ och solelbörs

This candidate thesis contains the possibility of expand the Swedish photovoltaic market through photovoltaic cooperatives and a photovoltaic exchange. In the current situation there is a lot of problems with production of electricity from photovoltaic, that?s why we show some possibilities how to avoid these. To understand the problem with photovoltaic produced electricity we first give you a background.We show how to expand the Swedish photovoltaic market by describing how a photovoltaic cooperative and photovoltaic exchange could work in Sweden. It have been confirmed from our market research that the interest of photovoltaic cooperative and exchange is high.To find out how profitable photovoltaic is in Sweden, have three projections been made.

Undersökning av energiförbrukning och konceptutveckling av mer energisnåla frukostmaskiner

This master thesis comprises analysis and dimensioning of a keyed joint between a generator axis and a hub with aid from the FEM-software ANSYS Workbench 13.0.The generator axis is a part of a hydroelectric power station that generates electricity with a reactions turbine, a Kaplan turbine. The existing keyway consists of one parallel key with the width 90 mm and height 45 mm. Due to a planned increase of the power of the generated power with 32 % a design study was needed to see if the keyed joint would be suitable for the extra force. Because of the fact that the axis diameter is bigger than the standards covers/recommends a the keyway had to be re-dimensioned. In an earlier assignment from Skellefteå Kraft AB to Sweco Energuide the keyway was planned to be properly dimensioned, but no final solution was approved.During this master thesis a number of different numerical tests were made.

Att vårda ett brustet hjärta : Kvinnors upplevelse av stöd vid akut hjärtsjukdom

Syfte och frågeställningarStudien genomfördes med syftet att specificera vilken intensitet och duration vid uppvärmning som är optimal för att få ut största möjliga effekt vid anaerob prestation i form av maximalt vertikalhopp och fem sekunders maximal cykelsprint. Studien byggde på tre frågeställningar: På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt vertikalhopp? På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt fem sekunders sprinttest? Vilken uppvärmning är optimal för maximal muskulär explosivitet?MetodDesignen var en kvantitativ experimentell studie som innefattade fyra fysiskt aktiva kvinnor med genomsnittsålder på 24 år. Testerna bestod av nio tillfällen där en slumpad uppvärmning på ergometercykel genomfördes varje gång. Därefter genomfördes tre vertikalhopp, så kallade counter movement jump, på en kraftplatta och tre fem-sekunders sprint (5sCST) på Monarks Peak Bike.

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