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MIMO is a wireless communication technology that is growing in popularity due to its ability to deliver significant improvements over conventional systems. However, some applications require antennas to be closely spaced, which results in strong coupling among the antennas and performance degradation. Here we show that in a random field, load impedance can play an important role in the power, corr
Bird brooches at Uppåkra have a changing biography, as grave gifts, pendants, and scrap metal. The association between bird brooches and birds of prey, and a male face to female jewellery opens questions of identy of the wearer and the male person in question. Following the bird brooches and the connotations of falconry decode both a social identiy and a lifestyle, expressed in the aestetics of th
The complex interplay by tunneling and scattering in quantum cascade lasers is analyzed with nonequilibrium Green's functions. Data for a recently proposed simple structure based on only two wells per period is presented. This simple structure allows to visualize the relevance of the tunneling resonance very clearly. It is argued that a QCL design needs at least three levels per period, thus furth
In an era of lifelong learning, empowerment of the learner becomes fundamental. Therefore ex-ploitation of the full potential of learning objects depends upon creation of an appropriate infra-structure to promote symmetrical control of inquiry. The learner needs to be empowered because learning is a discovery process and thus must be under his or her own control. In early stages of education it
The thesis presents the results of studies of aerosol particle formation using ion and electron beam analytical techniques. The sources of aerosol particle formation studied are the following: 1. production of primary aerosol particles in the high Arctic region during summers 2. emission of ultrafine aerosol particles from wear on the road-tire interface 3. emission of aerosol particles from di
