Sökning: "spektralanalys"

Visar resultat 1 - 5 av 8 avhandlingar innehållade ordet spektralanalys.

  1. 1. Hydrology and Bed Topography of the Greenland Ice Sheet : Last known surroundings

    Författare :Katrin Lindbäck; Rickard Pettersson; Francisco Navarro; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; climate change; Greenland Ice Sheet; radio-echo sounding; digital elevation models; ice thickness; bed topography; spectral analysis; roughness; subglacial hydrology; water piracy; englacial features; drainage catchments; meltwater runoff; ice dynamics; klimatförändringar; Grönlands inlandsis; markbaserad radar; digitala höjdmodeller; istjocklek; bottentopografi; spektralanalys; subglacial hydrologi; englaciala strukturer; avrinningsområden; isdynamik;

    Sammanfattning : The increased temperatures in the Arctic accelerate the loss of land based ice stored in glaciers. The Greenland Ice Sheet is the largest ice mass in the Northern Hemisphere and holds ~10% of all the freshwater on Earth, equivalent to ~7 metres of global sea level rise. LÄS MER

  3. 2. Topographic Control of Groundwater Flow

    Författare :Lars Marklund; Anders Wörman; Shulan Xu; Roy Haggerty; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Groundwater; Modeling; Topography; Spectral analysis; Fourier series; Exact solu-tions; Multi-scale; Grundvatten; Modellering; Topografi; Spektralanalys; Fourier serier; Analytisk lösning; Flerskalig; Hydrology; Hydrologi; Environmental engineering; Miljöteknik;

    Sammanfattning : Gravity is the main driving force for groundwater flow, and both landscape topography and geology distribute the effects of gravity on groundwater flow.  The groundwater table defines the distribution of the potential energy of the water. LÄS MER

  4. 3. Microwave spectroscopical investigations of some halogenated butadienes

    Författare :Per Cederbalk; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Spektralanalys;

    Sammanfattning : This thesis deals with microwave spectroscopical investigations of four mono-halogenated 1,3-butadienes. Two of the investigations are mainly concerned with the elucidation of complete molecular structures using the isotopical substitution method, whereas the other two deal chiefly with the determination of molecular charge distributions. LÄS MER

  5. 4. Spectral analysis in laser powder bed fusion

    Författare :Benedikt Brandau; Frank Brückner; Alexander Kaplan; Dan Roth-Fagaraseanu; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spectral monitoring; Laser powder bed fusion; Laser optics; Absorbance; Produktionsutveckling; Manufacturing Systems Engineering;

    Sammanfattning : This thesis is about the investigation of the spectral interaction of electromagnetic radiation with metal powders. For this purpose, spectral data of powders for laser powder bed fusion processes are investigated in three papers using different techniques. LÄS MER

  7. 5. Spectral Analysis for Signal Detection and Classification : Reducing Variance and Extracting Features

    Författare :Isabella Reinhold; Statistical Signal Processing Group; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multifönster; Tids-frekvensanalys; Instantaneous frequency; Multitaper; Signal resolution; Reassignment method; Time-frequency analysis;

    Sammanfattning : Spectral analysis encompasses several powerful signal processing methods. The papers in this thesis present methods for finding good spectral representations, and methods both for stationary and non-stationary signals are considered. LÄS MER