Sökresultat

Filtyp

Din sökning på "*" gav 528096 sökträffar

Some Control Applications in Electric Power Systems

Popular Abstract in Swedish Denna avhandling presenterar några reglertekniska tillämpningar i elkraftsystem. Tillämpningarna är: hur likströmskablar påverkar båtrafik som använder magnetkompasser; frekvensmätning i elkraftsystem; algorithmer för datorbaserade reläskydd; koppling av aktiv last för att dämpa effektpendlingar.This thesis presents some control applications in electric power systems. The work consists of the four parts: interaction between DC cables and ship steering autopilots; frequency estimation; computer relaying; field tests using load switching to damp power oscillations. The first three parts are based on four papers that are given in Appendix A-D. The thesis presents supplementary text to these

Towards a Theory of Codes for Iterative Decoding

Channel codes in combination with iterative decoding techniques are a both powerful and efficient method to protect data against disturbances in digital communication systems. This thesis deals with various code constructions for block-wise and continuous transmission that have the potential to achieve low bit error rates with iterative decoding, even when operating close to the Shannon limit. Fo

Isotope-Selective Spectroscopy: Fast Timing R&D and fp-Shell Mirror Isomers

This thesis highlights the research and development of a new plastic-scintillator detector for time-of-flight measurements in relativistic heavy-ion beam experiments. The detector makes possible the identification of different ion species on flight distances as short as a few meters. The novelty lies in the design approach of using many moderately fast, independent measurements of every physical e

Model development for estimating carbon dioxide exchange in Nordic forests and peatlands with MODIS time series data

Popular Abstract in Swedish Den pågående ökningen av växthusgaser i atmosfären orsakar en ökning av den globala medeltemperaturen. En viktig påverkande faktor för koncentrationen koldioxid (CO2) i atmosfären är utbytet mellan atmosfären och biosfären; fotosyntesen tar upp CO2 och respirationen släpper ut CO2, vilket resulterar i ett nettoutbyte. För att öka vår förståelse av den spatiala och tempoThe ongoing increase in atmospheric greenhouse gas concentrations causes an increase in the global mean air temperature. One important moderator of the atmospheric carbon dioxide (CO2) concentration is the gas exchange between the atmosphere and the biosphere; photosynthesis extracts and respiration releases CO2, resulting in a net exchange. A variety of methods are used to improve our understandi

The Strategic Grounding of Competitive Advantage - The Case of Scania

Scania has performed well above average in the heavy truck industry during a considerable time span. Scania's sources of competitive advantage are presented and their interrelations and significance for the business strategy analysed in order to explain the success of Scania. Strategic issues are traditionally analysed in a top-down procedure starting with the corporate strategy and proceeding by

Advances in Stellar Astrophysics from Laboratory Spectroscopy

Popular Abstract in Swedish Om man betraktar ljuset fran en varm gas ser man att det har en viss färg som är beroende gasens kemiska sammansättning. Består gasen av endast ett ämne kan man genom att detaljstudera ljuset erhålla information som är specifik för just detta grundämnet. For varje grundämne finns ett mönster av spektrallinjer som bygger upp ämnets spektrum. Om spektrumen for många ämnenInvestigation of astrophysical plasmas, such as stellar atmospheres, require both knowledge of atomic structure and data. We present laboratory instruments, techniques and tools for acquisition of the data required to derive important atomic parameters such as, wavelengths, oscillator strengths and line profiles. In this thesis new atomic data for advancement of stellar atmosphere analysis are pre

Defect Sensitivity and Strength of Paperboard in Out-of-Plane Tension and Shear

Abstract in French La présente communication examine les effets du fissurage sur les causes des défaillances dans le sens de l'épaisseur d'un carton multicouches. Nous avons étudié comment la valeur de contrainte maximum relative change en fonction de la longueur des fissures dans diverses conditions de charge. Des feuilles d'essai comportant des fissures de fabrication dans le sens parallèle au pThis paper considers the effects of defects in the form of cracks on the failure properties in the thickness direction of multilayered board. The objective was to study how the peak stress value changes with various crack lengths under various load conditions. Specimens with manufactured cracks cut parallel to the machine-direction–cross-machine-direction plane were glued in the Arcan device and t

Genetiska konflikter. Polemiska artiklar från trettio år

Kunskap är makt, vilket betyder att med genetisk kunskap följer anspråk på makt över livet, människorna och tankarna. Men anspråk på makt möter motanspråk. Därför har genetisk kunskap alltid genererat konflikter. Dessa handlar sällan om genetiken själv. Istället handlar de om makt-anknutna anspråk. Hur fullständig är egent-ligen kunskapen som våra genetiska undersökningar ger? Räcker den till för