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Solen och alla stjärnor som vi ser på natthimlen tillhör vår Galax - Vintergatan. Vintergatan är en spiralgalax med en utbuktning i dess centrum - bulben. För att förstå hur Vintergatan blev till måste man ha en bra uppfattning om bulbens ursprung. Under många år trodde vi att vi visste hur bulben och hela Galaxen hade formats, men ny teknologi, förbättrade teleskop och instrument samt simuleringaContext. The formation and evolution of the Galactic bulge and the Milky Way is still a debated subject. Observations of, e.g., the X-shaped bulge, cylindrical stellar motions and young stars in the bulge have suggested that the bulge formed through secular evolution of the disk and not through gas dissipation and/or mergers, as thought previously.\\ Data. We use high-resolution optical spectra of

Vår galax, Vintergatan, innehåller bortåt 200 miljarder stjärnor av varierande åldrar och storlekar. Under en mörk och klar natt kan man se ungefär 2000 med blotta ögat. Detta är en liten del av det stora hela, men tillräckligt för att stimulera människors nyfikenhet. Vad är de gjorda av, och varför är de där de är? Enkla frågor, som har väldigt komplexa svar. Genom att kartlägga strukturen och deContext. Large scale chemical abundance gradients in the Galactic disks, small-scale abundance structures, and the mean chemical abundance values in the Solar vicinity, are important constraints to Galactic chemo-dynamical formation and evolution models. The formation and evolution of stars, and interstellar gas and dust depends on the distribution and evolution of matter in the Galaxy. Therefore,

Stjärnorna på himlen syns vara små eftersom de är avlägsna objekt, solar på enorma avstånd. Den närmaste stjärnan är Alfa Centauri på ett avstånd av 4,4 ljusår, cirka 41 miljon miljoner kilometer. Solen är den enda stjärna vars yta vi kan se i detalj medan andra stjärnor är så avlägsna att de inte ens i de största teleskopen syns som mer än små ljusa prickar. De skarpaste bilder som i dag erhållContext. Intensity interferometry was invented and used by R.Hanbury Brown and R.Q.Twiss in the 1960's to measure stellar angular diameters. Its main advantage over conventional interferometry is that it enables very long baselines and is insensitive to poor seeing. However, because it requires very large light collectors, it was never pursued further. The Cherenkov Telescope Array (CTA) is a

Popular Abstract in Swedish Undersökningar av astrofysikaliska spektra kräver noggranna atomära data, som t.ex. våglängder och övergångssannolikheter. Denna avhandling bidrar med atomära data av hög precision för astrofysikaliska och kosmologiska tillämpningar. Mätningarna har gjorts på ljus producerat i en hålkatodlampa med hjälp av Fouriertransformspektrometri. Genom att observera våglängdsskifInvestigations of astrophysical spectra require accurate atomic data, such as wavelengths and transition probabilities. This thesis provides high-precision atomic data for astrophysical and cosmological applications. The measurements have been carried out using Fourier transform spectrometry on light produced in a hollow cathode light source. The variability of fundamental constants is investigat

Popular Abstract in Swedish Denna avhandling behandlar komplexa optimerings problem med artificiella neuron nätverk (ANN) tekniker och diverse verktyg från den teoretiska fysiken. För många typer av komplexa optimerings problem kan den mänskliga hjärnan prestera ett snabbt och hyfsat bra svar. ANN bygger på en mycket rudimentär bild av hur det riktiga de riktiga neuronerna i hjärnan arbetar, syftPotts mean field artificial neural network techniques are developed and applied to airline crew scheduling problems and routing problems. A propagator formalism in terms of Potts neurons is developed to handle global topological issues. An integrated method for identifying and classifying ECG complexes is presented. Unsupervised self-organizing artificial neural networks are employed to cluster t

Popular Abstract in Swedish Hur ser det ut inuti protonen? Vi vet att protonen består av mindre partiklar. Den utgörs egentligen av tre st. kvarkar, men där finns också en mängd gluoner och virtuella kvarkar och antikvarkar. Gluonerna är de partiklar som håller ihop de tre kvarkarna (valenskvarkarna) i ett så hårt grepp att protonen blir väldigt liten (ca. 100000 ggr mindre än en atom). Det är deIn this thesis, we give a description of the detailed structure of the proton and a description of the final-state properties in electron-proton scattering. Qualitative results, in a purely gluonic scenario with the leading log approximation, and quantitative results, where quarks are included and some sub-leading corrections have been made, are presented. The quantitative results are in fair agre

I många däggdjurs hjärnor pågår en process som kallas "synaptic pruning", som går ut på att göra sig av med hjärnans mindre använda kopplingar. Likt detta kallar man processer för ta bort överflödiga objekt från neuronnätverk för "pruning". Ett av de ursprungliga sätten att åstadkomma detta var det så kallade "optimal brain damage", som definierade ett sätt att sorterIn this study, the efficiency of various pruning algorithms were investigated, with an emphasis on regularization methods. Pruning is a method which aims to remove excess objects from a neural network. In particular, this included the LASSO (Least Asbolute Shrinkage and Selection Operator) and the extensions derived from it, which were compared with other methods, including optimal brain damage an

The decay of solutions to the Klein-Gordon equation is studied in two expanding cosmological spacetimes, namely (1) the de Sitter universe in flat Friedmann-Lemaitre-Robertson-Walker (FLRW) form, and (2) the cosmological region of the Reissner-Nordström-de Sitter (RNdS) model. Using energy methods, for initial data with finite higher order energies, bounds on the decay rates of the solution are obOne of the most profound realisations of physics of the twentieth century is that space and time should be considered as a single whole, a four-dimensional geometric object called spacetime, rather than two separate entities. Gravitation arising from matter manifests itself as curvature of spacetime, and the motion of matter is described by the straightest possible curves on this curved spacetime.

The aim for this report is to present an industrial design master thesis carried out by Micael Palmgren at Lunds University. The report describes, not only the end result of the project, but also the path along the line to the final result. The master thesis have developed and visualized a unique concept for a new motorboat for tomorrow, called Gränö 750 ME. The reader will be taken through the de

This dissertation is about the view of writing. One of the intentions of the study is to analyse different notions of writing that become manifest in media debates about student writing. Another intention is to analyse conceptions of writing in curricula and course plans for upper secondary school in Sweden from 1970 to 2011. Drawing from theories of critical discourse analysis, the study aims atThis dissertation is about the view of writing. One of the intentions of the study is to analyse different notions of writing that become manifest in media debates about student writing. Another intention is to analyse conceptions of writing in curricula and course plans for upper secondary school in Sweden from 1970 to 2011. Drawing from theories of critical discourse analysis, the study aims at

Feature stability, time and tempo of change, and the role of genealogy versus areality in creating linguistic diversity are important issues in current computational research on linguistic typology. This paper presents a database initiative, DiACL Typology, which aims to provide a resource for addressing these questions with specific of the extended Indo-European language area of Eurasia, the regiFeature stability, time and tempo of change, and the role of genealogy versus areality in creating linguistic diversity are important issues in current computational research on linguistic typology. This paper presents a database initiative, DiACL Typology, which aims to provide a resource for addressing these questions with specific of the extended Indo-European language area of Eurasia, the regi

Taking a historical perspective, this article compares the four Nordic states of Denmark, Finland, Norway and Sweden with respect to the following question: How have problem representations developed the Nordic region’s policy response to the exploitation of migrant workers? We demonstrate that parallel and competing problem representations, defined in government policy as ‘human trafficking’, ‘foTaking a historical perspective, this article compares the four Nordic states of Denmark, Finland, Norway and Sweden with respect to the following question: How have problem representations developed the Nordic region’s policy response to the exploitation of migrant workers? We demonstrate that parallel and competing problem representations, defined in government policy as ‘human trafficking’, ‘fo