Sökning: "polarization fields"

Visar resultat 1 - 5 av 83 avhandlingar innehållade orden polarization fields.

1. 1. Computing abelian varieties over finite fields

   Författare :Stefano Marseglia; Jonas Bergström; Christophe Ritzenthaler; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; abelian varieties; finite fields; period matrices; ideal classes; orders; number fields; integral matrices; Mathematics; matematik;

   Sammanfattning : In this thesis we address the problem of developing effective algorithms to compute isomorphism classes of polarized abelian varieties over a finite field and of fractional ideals of an order in a finite product of number fields.There are well-known methods to efficiently compute the classes of invertible ideals of an order in a number field, but not much has previously been known about non-invertible ideals. LÄS MER

3. 2. Polarization in the ELAIS-N1 LOFAR deep field

   Författare :Sara Piras; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ELAIS-N1; galaxies; polarization; polarimetric; radio continuum;

   Sammanfattning : The physical characteristics of cosmic magnetic fields are encoded in the po- larization properties of the extragalactic radio sources. Linearly polarized radiation undergoes Faraday rotation as it crosses a magneto-ionic medium; the rotation of the polarization angle of the signal is equal to its wavelength squared times the Rotation Measure (RM), that is proportional to the line- of-sight integral of the product of the magnetic field component along the line of sight and the density of thermal electrons. LÄS MER

4. 3. A first-principles approach to protein–ligand interaction

   Författare :Pär Söderhjelm; Beräkningskemi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; solvation; exchange repulsion; polarizable force fields; polarization; molecular mechanics; quantum chemistry; intermolecular interactions; protein–ligand interaction;

   Sammanfattning : It is still impossible to make an accurate, purely theoretical prediction of the free energy of a ligand binding to a protein in aqueous environment. The two main problems are the immense number of nuclear configurations contributing to the binding free energy and the impossibility to apply accurate quantum-chemical methods to such a large system, even for a single configuration. LÄS MER

5. 4. Polarization-Resolved Particle Holography

   Författare :Johan Öhman; Mikael Sjödahl; Erik Olsson; Per Bergström; Pietro Ferraro; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Experimentell mekanik; Experimental Mechanics;

   Sammanfattning : In this thesis, measurement of particle fields using digital holography is the main subject. The questions investigated consider positioning, identification and sizing of nanometer and micrometer particles. The thesis explore these topics using both simulations and experimental measurements. LÄS MER

7. 5. A quantum-chemical study to the magnetic characteristics of methanol and its applications in astronomy

   Författare :Boy Lankhaar; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; methanol; maser polarization; star formation; magnetic fields; masers;

   Sammanfattning : Magnetic fields play an important role during star formation. Direct magnetic field strength observations have proven specifically challenging in the dynamic protostellar phase. LÄS MER