Thorkild B. Hansen

Learn More
The plane-wave scattering matrix is used to characterize antennas that are located just above a planar interface that separates two media. The plane-wave transmitting spectrum for the field radiated downward into the lower medium is expressed directly in terms of the current distribution of the transmitting antenna. The transmitting spectrum for a(More)
Plane-wave representations are used to formulate the exact solutions to frequency-domain and time-domain sources illuminating a magnetodielectric slab with complex permittivity epsilon(omega) and permeability mu(omega). In the special case of a line source at z = 0 a distance d < L in front of an L-wide lossless double-negative (DNG) slab with kappa(omega(More)
The fate of 15NH4-N labelled cattle slurry applied before sowing in September of a winter wheat crop was studied on a loamy sand soil. The aim was to quantify immobilization of slurry 4 into microbial biomass, the speed at which nitrate derived from the slurry NH4-N was transported down the soil profile, and the utilization of slurry 4 by the winter wheat(More)
Time-domain planar near-field measurement techniques are formulated for acoustic and electromagnetic fields. Probe correction is ignored in that it is assumed that the probe measures the exact values of the field on the scan plane. Two fundamentally different approaches are used in deriving three sets of formulas that give the fields in the source-free half(More)
The current near a right-angled comer on a perfectly conducting flat scatterer illuminated by a plane wave is expressed as a sum of three currents. The first is the physical optics (PO) current, which describes the surface effect. The second is the fringe wave (FW) current, which is found from the half-plane solution and accounts for the distortion of the(More)
An experimental study is performed to investigate the ignition, devolatilization, and burnout of single biomass particles of various shapes and sizes under process conditions that are similar to those in an industrial combustor. A chargecoupled device (CCD) camera is used to record the whole combustion process. For the particles with similar volume (mass),(More)