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  • 28651.
    Törebrand, Johan
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Geography and Tourism.
    Thilén, Ulf
    Karlstad University, Faculty of Social and Life Sciences, Department of Geography and Tourism.
    Geodatasamverkan - nyttan för en kommun att delta2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Swedish model for developing the national infrastructure is based on increasing the cooperation between municipalities, government and businesses. The method to establish the infrastructure in Sweden is the geodatastrategin. The effort to implement the geodatastrategin has resulted in an interaction model, Geodatasamverkan.

     

    The purpose of this study is to alert municipalities and to investigate the usefulness of their participation in Geodatasamverkan. The study also presents examples of different applications where geodata can be used within a municipality.

     

    The report is based on literature reviews, surveys and interviews. Online Surveys were sent to some of Sweden's municipalities to get an overall idea of ​​how they make use of geodata and their general attitude towards Geodatasamverkan. Two different custom made questionnaires were sent out, one adapted to those municipalities that participate in Geodatasamverkan and one adapted to those who do not. Those who were asked are staff responsible for GIS at a total of 62 municipalities in Västra Götalands län, Dalarnas län, Örebro län and Värmlands län, which sums up to a total of 39 people.

     

    For a more detailed investigation, staff responsible for GIS at five different municipalities in Värmland were chosen for interviews. The interviewed persons were selected on the criteria that most municipalities can relate to the investigation. Within the selected municipalities the study includes municipalities with varying GIS activities and situations according to their participation in Geodatasamverkan.

     

    The result concludes that municipalities can benefit greatly from participating in Geodatasamverkan. However, it is necessary that geodata is used in a substantial way within the municipality, and that geodata is implemented in several administrations. Participation in Geodatasamverkan results in access for municipalities to a large amount of geodata for a minor fee. The survey shows that participating municipalities order more of the set-covering images, basic maps and elevation data compared to before. This is due to the previously high expenditures of this type of data. The administrative process to manage contracts and invoices decrease, since only one contract and one invoice needs to be dealt with for participation.

     

  • 28652.
    törebrand, marie
    et al.
    Karlstad University. Karlstad University, Faculty of Social and Life Sciences.
    tuma, andrea
    Karlstad University. Karlstad University, Faculty of Social and Life Sciences.
    Behandlingsmetoder för tandvårdsrädda barn i latensåldern2008Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

     

     

     

     

     

     

     

    Introduktion:

     

    Tandvårdsrädsla är en av de vanligaste rädslorna/fobierna i den industrialiserade delen av världen. Problemet är vanligare bland barn i latensåldern, ungdomar och unga vuxna än hos vuxna och tycks inte reduceras trots moderna behandlingsmetoder.Tandvårdsrädslans etiologi är komplex och har visat sig korrelera med faktorer som ålder, kön, besöksvanor inom tandvård, tidigare smärtsamma upplevelser, tandläkarens uppfattning, oral hälsa och psykosociala faktorer. Syfte: Syftet var att beskriva olika behandlingsmetoder av tandvårdsrädsla vid behandling av tandvårdsrädda barn i latensåldern.Metod: Studien genomfördes som en systematisk litteraturstudie. Resultat: Resultatet bygger på 16 kvantitativa artiklar. Dessa visade att det fanns många olika psykologiska och farmakologiska behandlingsmetoder för att behandla tandvårdsrädda barn i latensåldern. Psykologiska behandlingsmetoder kunde effektivt minska rädsla. Den mest använda psykologiska metoden var tell-show-do. Farmakologiska behandlingsmetoder med bensodiazepiner användes ofta för att få barn att samarbeta. Sedering med lustgas samt sedering med allmänanestetika reducerade barns tandvårdsrädsla. Slutsats: Det fanns väl fungerande behandlingsmetoder som kunde användas för att hjälpa barn att hantera sin ångest och rädsla och för att minska negativt beteende som kunde störa tandvårdsbehandlingen.

  • 28653.
    Törlind, Virpi
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Eleven och atomen: En studie om svårigheter som elever har med atomen och dess egenskaper2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study is to shed light on difficulties that students have with the structure and properties of the atom within the initial chemistry part in the course Science studies 2. The study was conducted in two steps. First the students draw their atomic models and explained what they had drawn. At the same time they told about difficulties they experienced with the concept of the atom. The next part was conducted after completing the chemistry section in the course. Students were interviewed on the difficulties and how they would like to work with the concept of the atom. The interviews were transcribed and in the analysis work the answers were grouped according to similarities and patterns. The result showed that all the students needed to work more with the structure of the atom initially in the course. The students thought that the atom is abstract because of its size and because it is not found in their everyday contexts, many words are used within the atomic concept that the students have not worked with sufficiently. Some students also mentioned a poor teaching because of frequent teacher changes in compulsory school as the cause of the difficulties. The students wanted more conversation in the teaching, both to process concepts and the atomic concept, and for a more everyday use of the atom.

  • 28654.
    Törn, Emelie
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Halvardsson, Marie
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Nya Nederländska Satsningar: en studie om immigrerade entreprenörer i Värmland2009Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
  • 28655.
    Törnberg, Johanna
    Karlstad University.
    Marknadsmissbruk: Effektiv bekämpning av marknadsmissbruk genom införandet av MAR och MAD 22017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    KompL och LSM infördes i svensk rätt till följd av MAR och MAD 2. Den nya regleringen syftar till att utredning och bekämpning av marknadsmissbruk ska kunna bedrivas på ett effektivt sätt. Prop. 2016/17:22 har namnet ”effektiv bekämpning av marknadsmissbruk”. Vad som avses med effektiv bekämpning framgår inte av propositionen. Effektivitet är enligt min mening ett mått som behöver preciseras för att förstås. Eftersom begreppet inte förklarats genom prop. 2016/17:22 har det varit nödvändigt att dra egna slutsatser om vad regeringen menar med effektivitet. Utifrån propositionens innehåll, regleringen på EU-rättslig nivå och tidigare lagstiftning på området anser jag att det går göra antagande om hur effektivitet ska uppnås. För att uppnå effektivitet har finansinspektionen, genom den nya regleringen, fått utökade utredningsbefogenheter samt möjlighet att påföra administrativa sanktioner. Vidare har straffskalorna för marknadsmissbruk skärpts och marknadsmissbruksbrott har fått ett bredare tillämpningsområde.

    Antal inkomna brottsmisstankar angående marknadsmissbruk har sedan år 2005 ökat med 460 procent. Av de anmälningar som inkommit har det varit få anmälningar som lett till åtal. En bakomliggande faktor är att bestämmelserna om marknadsmissbruk varit svåra att tillämpa. Den lagstiftning som MAD 2 och MAR genererat i svensk rätt kommer troligtvis öka förutsättningarna för att utreda och bekämpa marknadsmissbruk på ett mer effektivt sätt än tidigare. Samtliga överträdelser av MAR är förbjudna oavsett uppsåt genom införandet av KompL och LSM. Den nya regleringen kommer sannolikt påverka antal anmälningar som leder till någon form av påföljd även om åtal inte väcks.

    Marknadsmissbruksbrotten består av marknadsmanipulation, insiderhandel och obehörigt röjande av insiderinformation. Tidigare var marknadsmissbruksbrotten definierade genom svensk lag. Genom den nya regleringen ska marknadsmissbruksbrotten tolkas och tillämpas i enlighet med definitionerna i MAR. Genom hänvisning till MAR kommer fler förfaranden omfattas av bestämmelserna i KompL och LSM.

    Uppdelningen mellan finansinspektionens och Ekobrottsmyndighetens befogenheter kommer sannolikt påverka att utredning av marknadsmissbruk kommer ske på ett mer effektivt sätt. Ekobrottsmyndigheten kommer inte utreda brott av mindre allvarlig karaktär till fördel för brott av mer allvarlig karaktär. Därigenom kan Ekobrottsmyndigheten fokusera på de mer allvarliga brotten som genom LSM kan påföras längre fängelsestraff. Finansinspektionen kan påföra administrativa sanktioner där subjektiva rekvisit utelämnas. Därigenom har finansinspektionen möjlighet att handlägga fler ärenden av administrativ karaktär. 

  • 28656.
    Törnberg, Johanna
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School.
    Uggla, Louise
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School.
    Arbetstagares rätt till uppfinningar och upphovsrättsskyddade alster: - Ersättningar, datorprogram och lärarundantag2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In pace with the development of technology it has become more common for companies to capture employees´ intellectual property rights. In most cases it is assumed that the companies have made agreements about the intellectual property rights such as copyright and patent law. In case there is no agreement there are regulations concerning the employees´ right to inventions.In copyright law the employees right to their subject matter isn’t vested, instead the agreement and principals are applied. In both fields of law, custom have an important role, particularly when it comes to the assessment regarding reasonable compensation in patent law.The copyright law can end in a conflict with several right areas, and the reason for that is because the employment relationship isn’t vested. It is an indication that a change is necessary for better harmonization between labour law, copyright law and patent law. The Act on the Right in Employee Inventions was added because the relationship between the employer and the employees previously wasn’t vested in Swedish law. It was previously unclear who the rights to an invention created in the service belonged too. We therefore question why the employment relationship isn’t vested.In patent law the rule regarding employees´ compensation is imperative. There is however uncertainties about what reasonable compensation is. The term reasonable has led to several disputes, but by the disputes no assessment template has developed. Thereby the difficulties of interpretation regarding the meaning of the concept still stand. Many litigation are judged in a closed settlement, which leads to further problems for the general courts to determine what reasonable compensation actually means. SOU 2010:24 comes with a proposal regarding that the compensation in copyright should be vested. To validate the compensation if the salary is not enough, can be needed, for example when it comes to science inventions. It can be established that the statutory regulation in the various areas are different from each other and it can become difficult if the right areas overlap. For example when it comes to computer programs and the exemptions for teachers.

  • 28657.
    Törnberg, Rebecka
    et al.
    Karlstad University.
    Edqvist, Emelie
    Karlstad University.
    Könsdiskriminering vid graviditet: Arbetsbrist som täckmantel2015Independent thesis Basic level (degree of Bachelor), 5 credits / 7,5 HE creditsStudent thesis
  • 28658.
    Törnberg, Rebecka
    et al.
    Karlstad University.
    Edqvist, Emelie
    Karlstad University.
    Livet efter idrottskarriären: En studie om övergången från idrottskarriären till en vanlig karriär2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Uppsatsens syfte är att undersöka övergångsfasen samt betydande faktorer för individen vid övergången från en idrottskarriär till en vanlig karriär. Den undersöker också vad som händer med individen när rollen som idrottare avslutas. Området är viktigt att undersöka eftersom allt fler idrottare går in i depressioner och liknande psykiska sjukdomar på grund av sitt arbete. Forskningsresultat visar att 10-15 % av alla idrottare som avslutar sin karriär upplever hjälplöshet, depression, oro, nedstämdhet, hög livsstress och andra psykologiska symptom (Bengtsson & Fallby, 2011). I teorikapitlet så förklaras de teorier som forskarna har valt att utgå ifrån för att besvara frågeställningarna. Utgångspunkten är socialpsykologiska och idrottspsykologiska teorier. Utifrån tidigare teorier så har en egengjord modell skapats över vilka faser som elitidrottare genomgår vid ett kärriäravslut. Studien är av kvalitativ metod och forskarna har genomfört en intervjustudie. I resultatdelen drogs slutsatsen att normativa övergångar upplevdes positivare än icke-normativa övergångar för idrottare. Forskarna kunde även urskilja problem med normativa övergångar, exempelvis om omgivningen såg negativt på avslutet eller om idrottaren inte fått chansen att avsluta på topp. En annan slutsats var att socialt stöd, målsättning och planering, identitet i balans, överförandet av idrottsegenskaper, motivation inför det nya yrket, upplevd framgång samt att fortsätta med träningen efter avslutad karriär var faktorer som var betydelsefulla för individerna. Forskarna drar även en sista slutsats att individen ofta vid en rollförlust förändrar sin identitet. En rollförlust blir jobbigare ju mer individen identifierat sig med rollen som idrottare. Förlusten blir än påtagligare om individen haft det Brewer (2001) kallar en gruppbaserad social identitet, vilket innebär att individen även förlorar sin identitet i gruppen som funnits med rollen som idrottare.

  • 28659.
    Törnblom, Cecilia
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Sjuksköterskans attityder till att vårda patienter med missbruksproblematik.: -En litteraturstudie2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Missbruk och beroende är pågående problem i vårt samhälle. Personer med missbruksproblematik drabbas ofta av ohälsa och komplexa tillstånd som kräver stora resurser från vården. Patienter med missbruksproblematik kan vara krävande både för vården som organisation och för sjuksköterskan som individ. Syftet var att undersöka sjuksköterskans attityder till att vårda patienter med missbruksproblematik Metoden var en litteraturstudie. Totalt nio artiklar som sökts fram i databaserna PubMed, Cinahl och PsycINFO kvalitetsgranskades enligt Polit och Becks granskningsmall och byggde upp studiens resultat. Resultatet visar generellt en negativ inställning bland sjuksköterskor till att vårda patienter med missbruksproblematik. Slutsats: Trots generellt negativ attityd finns det fåtalet sjuksköterskor som känner tillfredställelse i sitt arbete.

  • 28660.
    Törnblom, Linda
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies.
    Kursplanens betydelse för eleverslärande: Hur några elevers kunskap om kursplanen i fysik påverkar deras lärande2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of my study is to evaluate what knowledge some Swedish fifteen year old

    students’ in 9

    th grade had about the syllabus in physics, and how they perceive that the

    knowledge affects their learning process. The method, six qualitative interviews which is used

    in the evaluation, is chosen by the principles which can be found in studies of social science.

    One of the conclusions drawn from the study is that if students communicated knowledge

    about what the syllabus is and its purpose, it could be used as an artefact in the socio-cultural

    perspective of learning to improve motivation and increase the learning process. Over all, the

    syllabus is a very small part in what impacts the learning process in the formative assessment.

    Even difficulties in understanding concepts and the differences in concepts as syllabus,

    knowledge requirements and the content of importance has appeal in the process. In the

    perspective of social culture, communication of the syllabus can be seen as a resource in the

    learning processes.

  • 28661.
    Törner, Amanda
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013).
    ”De måste bara våga tro på oss”: En kvalitativ studie om tjejdomares upplevelser av miljön vid domarutbildningar och vid deras vardagliga verksamhet2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Since its beginning, sports have been defined by men for men, but nowadays women are welcome in to the sport-sphere. Women in sports are first and foremost active themselves and not as officials or volunteers of any kind, an area dominated by men. Purpose: The purpose of this study is to examine how girls who are football referees experience the environment of their officialdom, both at ordinary games and in an educational environment at courses. Literature: The theories supporting this study are Hirdmans gender contract (2003) and Butlers heterosexual matrix (2007). Method: To conduct this study, a qualitative method of semi-structured interviews has been used. Six girls who have gone through the course at the tournament Sverigecupen and are or have been active as referees the latest years participated in the study. Result: The analysis of the interviews showed that the respondents didn’t take damage by the rough climate girls who are referees meet in their profession. Although they still thought that courses for girls only could be good for younger referees. Difficulties at the girls’ ordinary games outside of tournaments were also mentioned. Discussion: Altogether the girls thought that a girls only-course would be a good complement to the courses of today, and that a lot can be done by initiating role modeling in the daily occupation of female referees.

  • 28662.
    Törner, Amanda
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    "Domarjävlarna", hur orkar de?: En kartläggning av elitdomare i fotboll och deras syn på domaryrket2016Student paper second term, 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    On a football field games are played between two teams, and the players of these teams get almost all of the attention. But there is another team on the field, the team of referees. The referees get mostly negative criticism, and are almost never mentioned in a positive way. This study is all about the teams’ captain, the main referee. Who is he? What does he have to go through? What makes him continue in his career?

     

    Earlier studies have shown that the work you do as a referee can be very stressful, with a lot of stressing factors coming from the players, the coaches, and at a higher level supporters and media (Nyberg, 2000, 2002). Because of all this, this study shows opinions from active referees in Allsvenskan in Sweden, and from some which are active on an international basis as well. Interviews have been made and a survey to compare the referees experiences with their sense of coherence, from Aaron Antonovskys theory SoC (Sense of Coherence).

     

    The results are showing that yes, there are connections between a successful career as a referee and a high level of sense of coherence, and that the interviewed referees’ spend a huge amount of time to be able to perform. Even though they try their hardest, they have to deal with threats in their daily work. Therefore, you can find the conclusion that you need to have a certain type of personality to be able to make it as a referee.

  • 28663.
    Törngren, Jesper
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Modulhus som passivhus: Undersökning på modulhus lämplighet att uppnå passivhusstandard med hjälp av byggnadstermografi och energiberäkningar2017Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Byggnads- och servicesektorn står för en stor del av den totala energianvändningen i Sverige och människan är idag väl medveten om konsekvenserna vid hög energianvändning. För att minska energianvändningen har det utvecklats energisnåla hus t.ex. passivhusen. Ett passivhus är välisolerat och tätt vilket medför att det blir energieffektivt.Modulhus i trä medför flera positiva egenskaper, trä är förnyelsebart och har en lägre påverkan på koldioxidutsläpp i förhållande till det flesta andra byggnadsmaterial. Modulhus kortar ner byggprocessen jämfört mot platsbyggnation vilket är bra då det råder bostadsbrist.En modulbyggnad uppfört i trä har undersökts med termografering och energiberäkningar. Med målet att undersöka om en modulbyggnad kan uppnå passivhusstandard. Med termograferingen har byggdelar samt anslutningar mellan byggdelar kontrollerats. Energiberäkningsprogrammet VIP-Energy har använts för att utvärdera byggnadens energiprestanda. Det har konstruerats ett alternativ på hur modulhuset kan utformas i passivhusstandard.Termografiundersökning tyder på att byggnaden har flera köldbryggor, varav ett fåtal bör åtgärdas för att uppnå passivhuskraven. Köldbryggor som uppstår oregelbundet i modulskarvar behöver minimeras eller utebli helt för att uppnå passivhusstandard. Balkonginfästningarna i byggnaden utgör återkommande köldbryggor som behöver justeras för att uppnå passivhusstandard. Energiberäkningarna visar att det är klart möjligt att uppnå passivhusstandard för byggnaden. Värmeförlusttalet för byggnaden klarar passivhuskraven.

  • 28664.
    Törnkvist, Fredrik
    Karlstad University, Faculty of Social and Life Sciences.
    Järn och en stads grundande: – Filipstad ur ett lokal- och mikrohistoriskt perspektiv2010Student paper other, 15 credits / 22,5 HE creditsStudent thesis
  • 28665.
    Törnqvist, Annika
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Nyanlända elever i grundsärskolan: Grundsärskolelärares beskrivningar av pedagogiska förutsättningar i undervisningen av nyanlända elever2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med den här studien är att bidra till kunskapsutvecklingen rörande undervisningens pedagogiska förutsättningar vad gäller nyanlända elever i grundsärskolan.

     

    De senaste åren har ett flertal nyanlända elever mottagits i den svenska grundsärskolan. Undervisning av tvåspråkiga elever med utvecklingsstörning ställer höga krav på lärarna då inte bara funktionsvariationerna kräver specialpedagogisk kompetens utan även språkförbistringar ska överbryggas. För att undersöka hur grundsärskolelärare som undervisar nyanlända elever beskriver detta har semistrukturerade intervjuer genomförts med fem lärare. Deras svar har sedan analyserats med hjälp av Bronfenbrenners (1979) ekologiska systemteori.

     

    Studien innehåller även en forskningsöversikt med både nationell och internationell forskning och då framförallt forskningsresultat utifrån tvåspråkiga elever i behov av särskilt stöd. Forskningen visar att tillgång till modersmålsundervisning är en viktig del i tvåspråkiga elevers språkutveckling, både vad gäller modersmålsutvecklingen och andraspråksutvecklingen. Forskningen påvisar även vikten av att frekvent utsättas för båda språken och då helst med tillgång till språkstöd på både modersmålet och andraspråket för att i undervisningen få till en så optimal kunskapsutveckling som möjligt hos eleverna.

     

    Studiens resultat visar att de intervjuade grundsärskolelärarna beskriver en fungerande kommunikation som den viktigaste ingrediensen i arbetet med nyanlända elever. För att lyckas med detta så använder sig lärarna ofta av olika tekniska och icke-tekniska kommunikationshjälpmedel. Vidare beskriver de en näst intill total brist på alla former av språkstöd för sina nyanlända elever. Modersmålsundervisning ges bara några elever tillgång till och då endast korta stunder. Studiehandledning saknades för alla elever och ingen av de intervjuade lärarna ansåg att de hade tillgång till språkstödjare i klassrummet. 

  • 28666.
    Törnqvist, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    En osäkerhetsundersökning av GNSS-mottagare2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    Today, GNSS measurements play an important role in the surveying industry, and their use is ever increasing. Many different GNSS receivers and antenna manufacturers are on the market with new ones appearing.

    The purpose of this study is to investigate the level of measurement uncertainty of three different GNSS receivers: Leica GS15, Sokkia GCX2 and Satlab SL300.

    The method in this study is based mainly on the method proposed by HMK - Geodatakvalitet 2015 (Manual in measurement and map issues – Geographic data quality 2015 [author’s translation]) by Swedish Lantmäteriet for "Evaluation of measurement uncertainty in Network RTK [author’s translation]”. Some corrections and additions are made to this method but the basis of the method is retrieved from there. Formulas are used to calculate radial deviation and limit requirements for these. Even standard deviations and radial mean deviations as well as tolerances for these are calculated. The field measurements are made on two RIX 95-points. This is done repeatedly to get up to 20 measurements. The GNSS receivers are mounted on a tripod with a tribrach that is centered over the known points.

    The main finding from this study is that all investigated receivers, apart from four overriding values ​​for the Leica GS15, perform better than specified by their manufacturers. However, Sokkia GCX2 and Satlab SL300 are approved with uncertainties within the calculated tolerances. The Leica GS15 instrument is very close to meeting the demands but does not reach all the way. A committed error during the performed measurements with the Satlab SL300 makes its evaluation based on 19 instead of 20 measurements. Still, calculations are performed on the collected data that resulted in low measurement uncertainties well below the manufacturer's specified uncertainty.

    The study was conducted during five weeks in May and June 2017.

  • 28667.
    Törnqvist, Martina
    Karlstad University.
    Skogen som lärmiljö2013Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 28668.
    Törnqvist, Veronica
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013).
    Flitiga flickor och omogna pojkar: En studie av lärares erfarenheter av att arbeta med anpassningar och stöd till elever i läs- och skrivsvårigheter2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study was to examine a selection of teachers’ experiences of working with adaptation and support for students with reading and writing difficulties.

    Adaptation and support should be immediately addressed to students with reading and writing difficulties according to the Swedish Agency for Education (2017).

    The Adaptations and support fields are lesser researched areas of reading and writing difficulties. This study is based on interviews with six teachers and the teachers were interviewed with semi-structured interviews. This study has a gender perspective and is based on gender as an active process that is constantly changing. Even hidden assumptions guiding gender is constantly affecting thoughts and reasons. Hardings (1986) gender model with three continuing processes in symbolic, structure and individual levels was used to analyse the study.

     

    The results show that the most common ways of paying attention to students in need of adaptations and support for reading and writing difficulties are when the teacher listens when the student reads high through different screenings. The teachers say they notice boys and girls equally. Intensive training of the students reading ability and the usage of compensatory aids are the most common adaptations and support methods. Difficulties for boys tend to follow them through the school years despite adaptations and support. The results from the study show that boys more often than girls have problem with concentration, attention and motivation in combination with reading and writing difficulties. The teachers in the study describe girls as diligent and boys as immature and sloppy. According to the teachers the boys also experience poorer child support. The analysis shows that at the symbolic level there are differences in the characteristics of boys and girls attributed to the teachers and on individual level there are writing and motivational differences between boys and girls. Boys are described to have less motivation and writing skills compared to girls. Girls are described to be vivid book readers whilst boys are thought of as non-readers. Support from colleagues and special education teachers are emphasised by all of the teachers so they can provide the best possible read and writing development support.

     

  • 28669.
    Törnros, Dennis
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Business Administration.
    Service for Free to Service for Fee: Implications derived from Service Infusion2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The concept service infusion implies that services are being included in a product-centric business to some extent. This movement towards integrating services will change how the business is performed in such a company; in other words, service infusion will lead to changes in the business model. This thesis aims to describe how service infusion affects the business in general and more specific effects in the business model.

    Volvo Trucks are somewhere in the process of service infusion and have several services offered to the market, such as Dynafleet, fuel advice, and driver training. In 2008, the service driver training was launched on the Romanian market and Volvo Trucks struggled with selling the service for a fee. This led to Volvo Trucks making the decision to start giving away the service for free. The objective of the service driver training was from the begging to sell it for a fee and the transition from service for free to service for fee is the main focus in this thesis.

    Through an analysis of the theoretical framework chosen for this thesis and a case study performed on Volvo Trucks, four success factors for the transition from free to fee could be identified: deep understanding of customers, show the value of the service, introduce sales commissions, and develop a pricing strategy. All these success factors are chosen to ease the transition from a service for free into a service for fee.

  • 28670.
    Törnvall, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    GNSS-mätning vid olika tidpunkter: En studie om osäkerhet2017Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to investigate whether different times during a day affect GNSSbased measurements. To investigate this, measurements were made on two known points at several occasions. The measurements compared are made in the morning, afternoon and evening. The points used are located in Östersund and in Hallen. The equipment that was used were a Nomad handheld computer and a TopCon Hiper II GNSS receiver with tripod and footer. The measurements were performed with NRTK in the coordinate system SWEREF99 14 15. The data was analyzed in SBG GEO and then compared in Microsoft Excel. The result was an average radial difference of 3 mm in plane. At three out of four times, the accuracy was better in the morning than in the afternoon/evening. The maximum difference between measurements was 8 mm.

  • 28671.
    Törsfeldt, Jenny
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Hedström, Linda
    Karlstad University.
    Fysisk aktivitet mellan förskola, förskoleklass och skola2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim is to provide knowledge about educators ' views on physical activity in the transition between preschool and school. The selection consisted of pre-school teachers, teachers, and teachers specializing in sport. In total, six individual interviews were conducted and a focus group with four people. The results of the study show that transitions can be a challenge for both preschool teachers, teachers and children. If there is major change too fast between school forms and unstructured, it can contribute to a precariousness in the transition for children. There may be a risk of a decrease in physical activity without a structured interaction where the staff have an interaction between each other and their respective activities, therefore this study be important for pre-school and school activities in Transitions. Preschool teachers and teachers see synergy as an opportunity to maintain play and physics activity in transitions. It was considered important to take part of each other's experiences and competencies from the different educational contexts. One conclusion in the study is that it can be a challenge to create a sustainable transition structure for children to be able to maintain physical activity with an increased age.

  • 28672.
    Tømmervold, Arne
    et al.
    Karlstad University, Division for Social Sciences.
    Bergan, Per Inge
    Karlstad University, Division for Social Sciences.
    Nerem, Vidar
    Karlstad University, Division for Social Sciences.
    Store opplevelser - små attraksjoner.: Destinasjonen Budors forutsetninger for innovasjon og utvikling.2006Independent thesis Basic level (professional degree), 10 points / 15 hpStudent thesis
    Abstract [en]

    The tourist industry is growing every year, together with the increasing competition among the travellers, both in Norway and in the rest of the world. The market for destination Budor is primarily Norway, and there are many important challenges waiting, both concerning marketing and innovation. Here we want to focus on the last mentioned item; innovation. We want to investigate if Budor has the appropriate conditions in order to continue competing for future costumers.

    We have done this by looking at both general and demographic developmental features connected to market and population, and we have especially been looking to the tourist industry and the building of Second homes.

    We have been investigating what kind of movements and innovations we see in the tourist business, and what Budor can do to meet these. We have been looking to Triple Helix theories as a power for innovations that Løiten Almenning could use, and finally we have investigated and analysed the creative climate and conditions for innovations in the organisation behind Budor; Løiten Almenning.

    Our opinion is that destination Budor has splendid natural conditions for both creativity and innovation. But, to cope with this you need cooperation and building of network together with national authorities, governmental business support apparatus i.e “Innovasjon Norge”, “FoU” and destination companies, and you need to believe in yourself and your own possibilities.

  • 28673.
    Tømte, Cathrine
    et al.
    NIFU, Nordic Institute for Studies in Innovation, Research and Education, Norge.
    Enochsson, Ann-Britt
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies.
    Buskqvist, Ulf
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies.
    Kårstein, Asbjørn
    NIFU, Nordic Institute for Studies in Innovation, Research and Education, Norge.
    Educating online student teachers to master professional digital competence: The TPACK-framework goes online2015In: Computers and education, ISSN 0360-1315, E-ISSN 1873-782X, Vol. 84, no May, p. 26-35Article in journal (Refereed)
    Abstract [en]

    In this article we study how online teacher education programmes may enhance innovative ways of teaching and learning with Information and Communication Technology (ICT). We explore how online teachers are practising professional digital competence, in general and within subject areas, and to what extent they encourage student teachers to develop their own professional digital competence. Based on online teacher education programmes at two distinct higher education institutions (HEIs), we applied mixed method design including quantitative and qualitative approaches to illuminate the aims and the scope. Our study revealed that even if online teacher education programmes represent good avenues for stimulating teachers and student teachers to develop digital competence for pedagogical purposes, this aspect is poorly integrated within the actual programmes, although some interesting examples were demonstrated. By looking at the origins of the discourses on online education and on digital competence, we found that they derive from different stakeholders: while the discourse on online education origi- nated from the management side at both HEIs, the discourse on digital competence derived from certain teaching staff at the two HEIs. Our study indicated that there is still some way to go to innovative so- lutions and to develop the potential of professional digital competence in online teacher education programmes. 

  • 28674.
    Udatsjen, Klas
    et al.
    Karlstad University, Division for Information Technology.
    Lind, Michael
    Karlstad University, Division for Information Technology.
    Konstruktion av LAN-anslutet moduluppbyggt styrsystem2006Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Our task from Special-Elektronik was to construct a LAN interfaced control system. The product may be used for controlling the light bulbs and reading the switches in a house, using available TCP/IP-network which decreases needed cable length.

    To solve the task we used a microcontroller, an Xport from Lantronix and a control server. The Xport works as a master module and translates the communication from TCP/IP to serial and back. As slave module we decided to use an ATMEGA8 microcontroller, in which we use 8 digital in- and outports.

  • 28675.
    Udd, Anton
    Karlstad University.
    Kollektivtrafikens vägskäl: Om kollektivtrafiklösningars påverkan på stadens struktur2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 28676.
    Udd, Sara
    et al.
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Geography, Media and Communication (from 2013).
    Zettergren, Eric
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Geography, Media and Communication (from 2013).
    Vad är boendeattraktivitet?: En studie av boendeattraktivitetens mening och betydelse i Dalarna2018Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Sammanfattning

    Studiens syfte är att ta reda på vad boendeattraktivitet innebär i Dalarna. Frågeställningarna innefattar dels ett regionalt perspektiv på begreppet boendeattraktivitet samt hur kommunerna i länet ser och förhåller sig till begreppet.

    • Hur beskrivs boendeattraktivitet på regionalnivå i Dalarna?
    • Hur ser kommunerna i Dalarna på begreppet boendeattraktivitet?

     

    För den regionala nivån står politiker och tjänstepersoner från Länsstyrelsen Dalarna som i en kvalitativ studieform intervjuas via en strukturerad intervjuguide. För frågan kring den kommunala nivån utgår studien från både en kvalitativ enkätundersökning där kontaktpersoner från respektive kommun kontaktas via mail med fem stycken frågor där de utan svarsalternativ fritt fick svara på frågorna. Det ingår även en dokumentstudie till den kommunala nivån där kommunernas översiktsplaner studeras och ordet attraktiv eller attraktivitet eftersöktes för att kunna urskilja mönster i dess användningsområde vilket summeras likt en kvantitativ ansatts i ett diagram. Enkätundersökningen och dokumentstudien jämförs sedan men varandra och får sedermera utgöra empirin för den andra frågeställningen

    Det teoretiska ramverket utgår från regionalism, attraktioner, Floridas kreativa klassen, Lee´s push & pull modell och Syssner och Anholts platsmarknadsföring. Tidigare studier från Telemarksforskning om attraktivitetens betydelse som illustreras till en attraktivitetspyramid, har även en central roll i studien.

    Resultatet av intervjuerna visar att det är omöjligt att peka ut en specifik faktor som är attraktiv, det varierar istället kraftigt beroende på individens livssituation. På den kommunala nivån däremot pekas sjönära läge ut som någonting särskilt attraktivt. Både från intervjuer och enkätundersökning går det att urskilja vikten av varierade lägen och boendeformer för att kunna uppnå en attraktivitet för majoriteten. I jämförelsen mellan enkätsvaren och dokumentstudien kunde det sammanfattas att ordet attraktiv används i marknadsföringssyfte och blivit allt vanligare med åren att använda sig utav.

    Studiens slutsats visar att boendeattraktivitet på regionalnivå kan angripas från tre olika håll. För invånare skiljer sig boendeattraktivitet beroende på deras livssituation. Attraktivitet kan mätas i fastighetspris, ett högre pris är lika med högre attraktivitet. För att kunna skapa attraktivitet i en region eller kommun krävs det variation i både lägen och boendeformer.

    Den kommunala nivån ser något annorlunda ut då de har möjlighet att utgå från sin egna geografiska avgränsning och dess förutsättningar. Även där angrips dock boendeattraktiviteten från tre håll. Det sjönära läget är det attraktiva läget i en kommun, kommunerna använder sig av begreppet boendeattraktivitet i platsmarknadsföringssyfte och liksom den regionala nivån krävs det variation för att kunna vara attraktiv för alla.

  • 28677.
    Udd, Stina
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013).
    Regional Utveckling, för Vem?: - en studie om hur inkluderande tillväxt kan arbetas in i det regionala utvecklingen i Värmland2015Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inom den regionala utvecklingen har ekonomisk tillväxt fått en allt större roll, fler och fler

    regioner arbetar efter att sträva en så hög ekonomiskt tillväxt som möjligt. Men i och med

    detta så skapas en geografiskt differentierad utveckling där de områden som genererar tillväxt

    anses har starka utvecklingsmöjligheter medan de områden som inte alls genererar lika

    mycket riskerar att hamna efter och bli outvecklade. Detta är något som kan ses i Värmland

    där Karlstadsregionen utvecklas medan de svagare delarna av länet, så som

    landsbygdsområdena inte alls har lika stort fokus på sig inom det regionala

    utvecklingsarbetet. En lösning på detta kan vara att arbeta fram en inkluderande tillväxt där

    det inte bara handlar om de ekonomiska värden utan även inkluderar sociala faktorer.

    Syftet med min studie är därför att lyfta fram och belysa frågor som rör inkluderande tillväxt

    på regional nivå med Värmland som fallstudie. Syftet är även att undersöka hur en mer

    inkluderad tillväxt kan arbetas in den regionala kontexten, samt se hur det regionala

    perspektivet och utvecklingsarbetet i Värmland kan påverkas av detta. Detta har jag gjort

    genom att utgå från två frågeställningar: Hur kan en inkluderande tillväxt arbetas in i den

    regionala kontexten och användas inom Värmlands regionala utvecklingsarbete? och vilka är

    effekterna som kan uppkomma om en inkluderande tillväxtstrategi arbetas in i det regionala

    utvecklingsarbetet i Värmland?

    Den hermeneutiska vetenskapsansatsen genomsyrar studiens teori, analys och bearbetning av

    empirin. Mitt perspektiv är socialkonstruktivistiskt. I min studie har jag utgått ifrån ett

    teoretiskt ramverk som har behandlat ämnena tillväxt, regionalism, regional utveckling,

    inkluderande tillväxt samt strategier för inkluderande tillväxt. I mitt empiriska material har

    jag fått tillhandahållit en enkätundersökning rörande tillväxt och utveckling i Värmland som

    är utformad inför en studie om ett interreg-projekt, samt kompletterat med redan bearbetat

    material från den värmländska SOM-undersökningen. Detta för att kunna skapa en förståelse

    för hur en inkluderande tillväxt kan arbetas in i en regional kontext och användas inom det

    regionala utvecklingsarbetet i Värmland.

    Det jag har kommit fram till i min studie är framförallt att det finns ett behov av att bredda

    tillväxtbegreppet så att det blir mer inkluderande, och att denna inkluderande tillväxten bör

    arbeta mer med sociala faktorer. För att kunna arbeta in detta i det regionala

    utvecklingsarbetet i Värmland bör det först och främst skapas en förståelse för att länet är så

    mycket mer än Karlstad samt att de måste se till hela befolkningens behov. Görs detta den

    största effekten bli att det skapas en mer geografiskt jämn utveckling i hela Värmland.

  • 28678.
    Uddegård, Susanne
    Karlstad University, Division for Social Sciences.
    Fritid -till vilket pris?: En intervjustudie om hur unga vuxna med fysiskt funktionshinder upplever möjligheter till en meningsfull fritid2007Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
  • 28679.
    Uddin, Md. Saffer
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    The Impact of Sensory Branding (five senses) on Consumer: A Case Study on "Coca Cola"2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 28680.
    Uddén, Rebecka
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies.
    Små barns interaktion med ofärdigt material: En kvalitativ studie om interaktion mellan barn och material2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 28681.
    Udéhn, Maria
    Karlstad University.
    Utvecklingen av antiepileptiska läkemedel 1953-2011 samt förskrivningen av ett urval 2006-2012 för barn och ungdommar 0-19 år2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 28682. Udén, G
    et al.
    Johansson, Inger
    Karlstad University, Faculty of Social and Life Sciences, Department of Nursing.
    Wilde-Larsson, Bodil
    Karlstad University, Faculty of Social and Life Sciences, Department of Nursing.
    Athlin, Elsy
    Karlstad University, Faculty of Social and Life Sciences, Department of Nursing.
    Kvalitetssäkring I omvårdnad1998Report (Refereed)
  • 28683.
    Ugarelli, Rita
    et al.
    Bologna university, Bologna, Italy.
    Govindarajan, Venkatesh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Brattebo, Helge
    Norwegian university of science and technology, Trondheim, Norway.
    Di Federico, Vittorio
    Bologna university, Bologna, Italy.
    Saegrov, Sveinung
    Norwegian university of science and technology, Trondheim, Norway.
    Historical analysis of blockages in wastewater pipelines in Oslo and diagnosis of causative pipeline characteristics.2010In: Urban Water Journal, ISSN 1573-062X, Vol. 7, no 6, p. 335-343Article in journal (Refereed)
    Abstract [en]

    The city of Oslo is evaluating strategies for the selection of appropriate materials for the pipelines and manholes of its wastewater network. The overarching motive is to minimise construction-related failures over the system lifetime and also ensure that it is able to avert flooding events. This paper analyses the blockage records of the last 16 years (1991-2006) in the wastewater pipeline network of Oslo. For the purpose of the analysis, the pipeline stock is categorised on the basis of pipe diameter, material of fabrication, slope and age. Proneness to blockages is studied and attempts are made to correlate the same to the size, material, slope and age. The analyses performed confirm that older and small diameter sewage pipelines made of concrete, laid almost horizontal to the ground surface are the high-priority candidates, and more importantly enables one to compare among the different categories and classes of pipelines.

  • 28684.
    Uggla, Anton
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Karlstad Business School (from 2013).
    Med betaltjänstdirektivet PSD2 som katalysator: Hur strategiska val och möjliga roller i värdekedjan påverkar den framtida marknadspositionen2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Även om marknaden för finansiella tjänster digitaliseras i en allt högre takt finns det fortfarandeinträdesbarriärer för nya aktörer som vill utveckla betal- och kontotjänster för konsumenter. Ettav dessa hinder är att infrastrukturen som används för tjänsterna ägs och förvaltas av deetablerade aktörerna vilket försvårar för en fri konkurrens. Som ett led i att bland annat öppnaupp den europeiska finansiella tjänstesektorn och främja innovation har EU därför infört ettandra betaltjänstdirekt (PSD2) som trädde i kraft under 2018. Direktivet omfattar etableradebanker och finansbolag och tvingar dem att exponera betaltjänster och kontoinformation tilltredjepartsleverantörer när kunden gett sitt medgivande. Införandet av PSD2 kommer förändraspelplanen för både etablerade och nya aktörer när befintliga affärsmodeller utmanas i takt medatt kunderna själva väljer finansiella tjänster efter tycke och smak.

    Denna kandidatuppsats syftar till att öka förståelsen för hur etablerade banker och finansbolagförhåller sig till möjligheterna och utmaningarna med att anpassa sina verksamheter i enlighetmed PSD2. Därtill är syftet att undersöka huruvida alternativet att inte ta upp kampen med nyaaktörer om de kundnära tjänsterna är en möjlig överlevnadsstrategi för de etablerade aktörerna.Den kvalitativa studien som ligger till grund för slutsatserna bygger på intervjuer somgenomförts med respondenter från två etablerade aktörer samt en ny aktör på den svenskabankmarknaden. Principerna för kvalitativ innehållsanalys har tillämpats vid strukturering ochanalys av intervjuerna.

    Resultatet visar att PSD2 även förväntas ge etablerade aktörer nya möjligheter attvidareutveckla sina tjänster genom att använda det tekniska ramverket utöver de regulatoriskakrav som direktivet föreskriver. I valet av strategi för PSD2 och de möjliga roller i värdekedjansom erbjuds finns det dock utmaningar med både den mest tillbakalutade och framåtriktademarknadspositionen eftersom dessa ställer krav som är svåra att leva upp till. PSD2 kommeräven medföra fler samarbeten mellan etablerade och nya aktörer som följd av att det finns ettömsesidigt beroende mellan parterna i ambitionen om att leverera den bästa kundupplevelsen.

  • 28685.
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Global cosmological dynamics for the scalar field representation of the modified Chaplygin gas2013In: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. D88, p. 064040-1-064040-7Article in journal (Refereed)
    Abstract [en]

    In this paper we investigate the global dynamics for the minimally coupled scalar field representation of the modified Chaplygin gas in the context of flat Friedmann-Lemaître-Robertson Walker cosmology. The tool for doing this is a new set of bounded variables that lead to a regular dynamical system. It is shown that the exact modified Chaplygin gas perfect fluid solution appears as a straight line in the associated phase plane. It is also shown that no other solutions stay close to this solution during their entire temporal evolution, but that there exists an open subset of solutions that stay arbitrarily close during an intermediate time interval, and into the future in the case when the scalar field potential exhibits a global minimum.

  • 28686.
    Uggla, Claes
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Recent developments concerning generic spacelike singularities2013In: General Relativity and Gravitation, ISSN 0001-7701, E-ISSN 1572-9532, Vol. 45, p. 1669-1710Article in journal (Refereed)
    Abstract [en]

    This is a review of recent progress concerning generic spacelikesingularities in general relativity. For brevity the main focus is on singularities in vacuum spacetimes, although the connection with, and the role of, matter for generic singularity formation is also commented on. The paper describes recent developments in two areas and show how these are connected within the context of the conformally Hubble-normalized state space approach. The first area is oscillatory singularities in spatially homogeneous cosmology and the connection between asymptotic behaviour and heteroclinic chains. The second area concerns oscillatory singularities in inhomogeneous models, especially spike chains and recurring spikes. The review also outlines some underlying reasons for why the structures that are the foundation for generic oscillatory behaviour exists at all, which entails discussing how underlying physical principles and applications of solutiongenerating techniques yield hierarchical structures and connections between them. Finally, it is pointed out that recent progress concerning generic singularities motivates some speculations that suggest that a paradigm shift concerning their physical role, and what mathematical issues to address,might be in order.

  • 28687.
    Uggla, Claes
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Spacetime singularities: Recent developments2013In: International Journal of Modern Physics D, ISSN 0218-2718, Vol. 22, no 3, p. 1330002-1330022Article in journal (Refereed)
    Abstract [en]

    Recent developments concerning oscillatory spacelike singularities in general relativity are taking place on two fronts. The first treats generic singularities in spatially homogeneous cosmology, most notably Bianchi types VIII and IX. The second deals with generic oscillatory singularities in inhomogeneous cosmologies, especially those with two commuting spacelike Killing vectors. This paper describes recent progress in these two areas: in the spatially homogeneous case, focus is on mathematically rigorous results, while analytical and numerical results concerning generic behavior and so-called recurring spike formation are the main topics in the inhomogeneous case. Unifying themes are connections between asymptotic behavior, hierarchical structures and solution generating techniques, which provide hints for a link between the nature of generic singularities and a hierarchy of hidden asymptotic symmetries.

  • 28688.
    Uggla, Claes
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    The Nature of Generic Cosmological Singularities2006In: Plenariebidrag "11th Marcel Grossmann Meeting on Recent Developments in General Relativity" (2006); även arXiv:0706.0463Article in journal (Refereed)
    Abstract [en]

    The existence of a singularity by definition implies a preferred scale--the affine parameter distance from/to the singularity of a causal geodesic that is used to define it. However, this variable scale is also captured by the expansion along the geodesic, and this can be used to obtain a regularized state space picture by means of a conformal transformation that factors out the expansion. This leads to the conformal `Hubble-normalized' orthonormal frame approach which allows one to translate methods and results concerning spatially homogeneous models into the generic inhomogeneous context, which in turn enables one to derive the dynamical nature of generic cosmological singularities. Here we describe this approach and outline the derivation of the `cosmological billiard attractor,' which describes the generic dynamical asymptotic behavior towards a generic spacelike singularity. We also compare the `dynamical systems picture' resulting from this approach with other work on generic spacelike singularities: the metric approach of Belinskii, Lifschitz, and Khalatnikov, and the recent Iwasawa based Hamiltonian method used by Damour, Henneaux, and Nicolai; in particular we show that the cosmological billiards obtained by the latter and the cosmological billiard attractor form complementary `dual' descriptions of the generic asymptotic dynamics of generic spacelike singularities

  • 28689.
    Uggla, Claes
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Vad händer då rum och tid upphör?2005In: Kosmos (2005) 65-91Article in journal (Other (popular science, discussion, etc.))
  • 28690.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Heinzle, J. Mark
    Röhr, Niklas
    The cosmological billiard attractor2009In: Advances in Theoretical and Mathematical Physics, ISSN 1095-0761, E-ISSN 1095-0753, Vol. 13, no 2, p. 293-407Article in journal (Refereed)
    Abstract

    This article is devoted to a study of the asymptotic dynamics of generic solutions of the Einstein vacuum equations toward a generic spacelike singularity. Starting from fundamental assumptions about the nature of generic spacelike singularities we derive in a step-by-step manner the cosmological billiard conjecture: we show that the generic asymptotic dynamics of solutions is represented by (randomized) sequences of heteroclinic orbits on the `billiard attractor'. Our analysis rests on two pillars: (i) a dynamical systems formulation based on the conformal Hubble-normalized orthonormal frame approach expressed in an Iwasawa frame; (ii) stochastic methods and the interplay between genericity and stochasticity. Our work generalizes and improves the level of rigor of previous work by Belinskii, Khalatnikov, and Lifshitz; furthermore, we establish that our approach and the Hamiltonian approach to `cosmological billiards', as elaborated by Damour, Hennaux, and Nicolai, can be viewed as yielding `dual' representations of the asymptotic dynamics

  • 28691.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    van Elst, Henk
    Wainwright, John
    Ellis, George F R
    The past attractor in inhomogeneous cosmology2003In: Phys.Rev. D68 (2003) 103502Article in journal (Refereed)
    Abstract [en]

    We present a general framework for analyzing spatially inhomogeneous cosmological dynamics. It employs Hubble-normalized scale-invariant variables which are defined within the orthonormal frame formalism, and leads to the formulation of Einstein's field equations with a perfect fluid matter source as an autonomous system of evolution equations and constraints. This framework incorporates spatially homogeneous dynamics in a natural way as a special case, thereby placing earlier work on spatially homogeneous cosmology in a broader context, and allows us to draw on experience gained in that field using dynamical systems methods. One of our goals is to provide a precise formulation of the approach to the spacelike initial singularity in cosmological models, described heuristically by Belinski\v{\i}, Khalatnikov and Lifshitz. Specifically, we construct an invariant set which we conjecture forms the local past attractor for the evolution equations. We anticipate that this new formulation will provide the basis for proving rigorous theorems concerning the asymptotic behavior of spatially inhomogeneous cosmological models

  • 28692.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Wainwright, John
    University of Waterloo, Canada.
    A simplified structure for second order cosmological perturbation equations2013In: General Relativity and Gravitation, ISSN 0001-7701, E-ISSN 1572-9532, Vol. 45, no 3, p. 643-674Article in journal (Refereed)
    Abstract [en]

    Increasingly accurate observations of the cosmic microwave background and the large scale distribution of galaxies necessitate the study of nonlinear perturbations of Friedmann–Lemaitre cosmologies, whose equations are notoriously complicated. In this paper we present a new derivation of the governing equations for second order perturbations within the framework of the metric-based approach that is minimal, as regards amount of calculation and length of expressions, and flexible, as regards choice of gauge and stress–energy tensor. Because of their generality and the simplicity of their structure our equations provide a convenient starting point for determining the behaviour of nonlinear perturbations of FL cosmologies with any given stress–energy content, using either the Poisson gauge or the uniform curvature gauge.

  • 28693.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Wainwright, John
    University of Waterloo, Canada.
    Asymptotic analysis of perturbed dust cosmologies to second order2013In: General Relativity and Gravitation, ISSN 0001-7701, E-ISSN 1572-9532, Vol. 45, no 8, p. 1467-1492Article in journal (Refereed)
    Abstract [en]

    Nonlinear perturbations of Friedmann-Lemaitre cosmologies with dust and a cosmological constant Lambda>0 have recently attracted considerable attention. In this paper our first goal is to compare the evolution of the first and second order perturbations by determining their asymptotic behaviour at late times in ever-expanding models. We show that in the presence of spatial curvature K or a cosmological constant, the density perturbation approaches a finite limit both to first and second order, but the rate of approach depends on the model, being power law in the scale factor if Lambda>0 but logarithmic if Lambda=0 and K<0. Scalar perturbations in general contain a growing and a decaying mode. We find, somewhat surprisingly, that if Lambda>0 the decaying mode does not die a way, i.e.  it contributes on an equal footing as the growing mode to the asymptotic expression for the density perturbation. On the other hand, the future asymptotic regime of the Einstein-de Sitter universe (K=Lambda=0) is completely different, as exemplified by the density perturbation which diverges; moreover, the second order perturbation diverges faster than the first order perturbation, which suggests that the Einstein-de Sitter universe is unstable to perturbations, and that the perturbation series do not converge towards the future. We conclude that the presence of spatial curvature or a cosmological constant stabilizes the perturbations. Our second goal is to derive an explicit expression for the second order density perturbation that can be used to study the effects of including a cosmological constant and spatial curvature.

  • 28694.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Wainwright, John
    Cosmological perturbation theory revisited2011In: Classical and quantum gravity, ISSN 0264-9381, E-ISSN 1361-6382, Vol. 28, no 17, p. 175017-175043Article in journal (Refereed)
    Abstract [en]

    Increasingly accurate observations are driving theoretical cosmology towards the use of more sophisticated descriptions of matter and the study of nonlinear perturbations of Friedmann–Lemaitre cosmologies, whose governing equations are notoriously complicated. Our goal in this paper is to formulate the governing equations for linear perturbation theory in a particularly simple and concise form in order to facilitate the extension to nonlinear perturbations. Our approach has several novel features. We show that the use of so-called intrinsic gauge invariants has two advantages. It naturally leads to (i) a physically motivated choice of a gauge invariant associated with the matter density, and (ii) two distinct and complementary ways of formulating the evolution equations for scalar perturbations, associated with the work of Bardeen and of Kodama and Sasaki. In the first case, the perturbed Einstein tensor gives rise to a second-order (in time) linear differential operator, and in the second case to a pair of coupled first-order (in time) linear differential operators. These operators are of fundamental importance in cosmological perturbation theory, since they provide the leading order terms in the governing equations for nonlinear perturbations

  • 28695.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Wainwright, John
    Univ Waterloo, Dept Appl Math, Waterloo, Canada.
    Dynamics of cosmological perturbations at first and second order2018In: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 98, no 10, article id 103534Article in journal (Refereed)
    Abstract [en]

    In this paper we give five gauge-invariant systems of governing equations for first and second order scalar perturbations of flat Friedmann-Lemaitre universes that are minimal in the sense that they contain no redundant equations or variables. We normalize the variables so that they are dimensionless, which leads to systems of equations that are simple and ready-to-use. We compare the properties and utility of the different systems. For example, they serve as a starting point for finding explicit solutions for two benchmark problems in cosmological perturbation theory at second order: adiabatic perturbations in the superhorizon regime (the long wavelength limit) and perturbations of ACDM universes. However, our framework has much wider applicability and serves as a reference for future work in the field.

  • 28696.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Physics and Electrical Engineering.
    Wainwright, John
    Scalar cosmological perturbations2012In: Classical and quantum gravity, ISSN 0264-9381, E-ISSN 1361-6382, Vol. 29, no 10, p. 105002-105029Article in journal (Refereed)
    Abstract [en]

    Scalar perturbations of Friedmann–Lemaitre cosmologies can be analyzed in a variety of ways using Einstein's field equations, the Ricci and Bianchi identities, or the conservation equations for the stress–energy tensor, and possibly introducing a timelike reference congruence. The common ground is the use of gauge invariants derived from the metric tensor, the stress–energy tensor, or from vectors associated with a reference congruence, as basic variables. Although there is a complication in that there is no unique choice of gauge invariants, we will show that this can be used to advantage. With this in mind our first goal is to present an efficient way of constructing dimensionless gauge invariants associated with the tensors that are involved, and of determining their inter-relationships. Our second goal is to give a unified treatment of the various ways of writing the governing equations in dimensionless form using gauge-invariant variables, showing how simplicity can be achieved by a suitable choice of variables and normalization factors. Our third goal is to elucidate the connection between the metric-based approach and the so-called 1 + 3 gauge-invariant approach to cosmological perturbations. We restrict our considerations to linear perturbations, but our intent is to set the stage for the extension to second-order perturbations

  • 28697.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Wainwright, John
    University of Waterloo, Canada.
    Second order cosmological perturbations: simplified gauge change formulas2019In: Classical and quantum gravity, ISSN 0264-9381, E-ISSN 1361-6382, Vol. 36, no 3, p. 1-19, article id 035004Article in journal (Refereed)
    Abstract [en]

    In this paper we present a new formulation of the change of gauge formulas in second order cosmological perturbation theory which unifies and simplifies known results. Our approach is based on defining new second order scalar perturbation variables by adding a multiple of the square of the corresponding first order variables to each second order variable. A bonus is that these new perturbation variables are of broader significance in that they also simplify the analysis of second order scalar perturbations in the super-horizon regime in a number of ways, and lead to new conserved quantities.

  • 28698.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Technology and Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Wainwright, John
    University of Waterloo.
    Second order density perturbations for dust cosmologies2014In: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. D90, p. 043511-Article in journal (Refereed)
    Abstract [en]

    We present simple expressions for the relativistic first and second order fractional density perturbations for FL cosmologies with dust, in four different gauges: the Poisson, uniform curvature, total matter and synchronous gauges. We include a cosmological constant and arbitrary spatial curvature in the background. A distinctive feature of our approach is our description of the spatial dependence of the perturbations using a canonical set of quadratic differential expressions involving an arbitrary spatial function that arises as a conserved quantity. This enables us to unify, simplify and extend previous seemingly disparate results. We use the primordial matter and metric perturbations that emerge at the end of the inflationary epoch to determine the additional arbitrary spatial function that arises when integrating the second order perturbation equations. This introduces a non-Gaussianity parameter into the expressions for the second order density perturbation. In the special case of zero spatial curvature we show that the time evolution simplifies significantly, and requires the use of only two non-elementary functions, the so-called growth supression factor at the linear level, and one new function at the second order level. We expect that the results will be useful in applications, for example, studying the effects of primordial non-Gaussianity on the large scale structure of the universe.

  • 28699.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Wainwright, John
    University Waterloo, Canada.
    Second-order cosmological perturbations: New conserved quantities and the general solution at super-horizon scale2019In: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 100, no 2, article id 023544Article in journal (Refereed)
    Abstract [en]

    The study of long-wavelength scalar perturbations, in particular the existence of conserved quantities when the perturbations are adiabatic, plays an important role in e.g., inflationary cosmology. In this paper we present some new conserved quantities at second order and relate them to the curvature perturbation in the uniform density gauge, zeta, and the comoving curvature perturbation, R. We also, for the first time, derive the general solution of the perturbed Einstein equations at second order, which thereby contains both growing and decaying modes, for adiabatic long-wavelength perturbations for a stress-energy tensor with zero anisotropic stresses and zero heat flux. The derivation uses the total matter gauge, but results are subsequently translated to the uniform curvature and Poisson (longitudinal, zero shear) gauges.

  • 28700.
    Uggla, Claes
    et al.
    Karlstad University, Faculty of Technology and Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics.
    Wainwright, John
    University of Waterloo.
    Simple expressions for second order density perturbations in standard cosmology2014In: Classical and quantum gravity, ISSN 0264-9381, E-ISSN 1361-6382, Vol. 31, no 10, p. 105008-Article in journal (Refereed)
    Abstract [en]

    In this paper we present four simple expressions for the relativistic first and second order fractional density perturbations for ΛCDM cosmologies in different gauges: the Poisson, uniform curvature, total matter and synchronous gauges. A distinctive feature of our approach is the use of a canonical set of quadratic differential expressions involving an arbitrary spatial function, the so-called comoving curvature perturbation, to describe the spatial dependence, which enables us to unify, simplify and extend previous seemingly disparate results. The simple structure of the expressions makes the evolution of the density perturbations completely transparent and clearly displays the effect of the cosmological constant on the dynamics, namely that it stabilizes the perturbations. We expect that the results will be useful in applications, for example, studying the effects of primordial non-Gaussianity on the large scale structure of the universe.

571572573574575576577 28651 - 28700 of 31133
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