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We consider a multiple input multiple output (MIMO) system wherein channel correlation as well as noisy channel estimation are both taken into account. For a given block fading duration, pilot-assisted channel estimation is carried out with the aid of a minimum mean square error estimator. The pilot sequences and data are jointly optimized to maximize the ergodic capacity while fulfilling a total

”Vad ska vi äta ikväll?” är en välbekant fråga för många. Mitt avhandlingsarbete tar sin utgångspunkt i hur småbarnsfamiljer (vår definition inkluderar familjer med barn upp till 8 år) förhåller sig till och får ihop vardagen när det kommer till mat, måltider och inköp. Att varje dag hinna med att tillaga en ordentlig måltid som ska smaka familjens alla medlemmar innebär inte enbart att utföra arb

In this paper we discuss AI in industrial robotics. In automatic control, computer vision and optimization, ma- chine learning and data mining algorithms are widely used. However, cognition enabling mechanisms, such as high-level logic and symbolic reasoning, are still limited. This is not due to the lack of available algorithms, rather the bottleneck is knowledge representation, acquisition and t

We take a logical approach to threshold models , used to study the diffusion of e.g. new technologies or behaviors in social net-works. In short, threshold models consist of a network graph of agents connected by a social relationship and a threshold to adopt a possibly cascading behavior. Agents adopt new behavior when the proportion of their neighbors who have already adopted it meets the thresh

Popular Abstract in Swedish Syn är avgörande för många djurs överlevnad. En väldigt viktig del av ögat är linsen då ljuset fokuseras genom den. I denna studie har jag undersökt hur fisklinser fokuserar ljus. Valet av fiskar som försöksdjur berodde på att de är lätta att skaffa och deras linser är klotformade, vilket underlättar beräkningen av strålgången och linsens optiska egenskaper. Hos fiskar Vision is an important source of information for many animals. The lens plays a central role in the visual pathway and hence the ecology of these animals. Fish have spherically shaped crystalline lenses that contain a gradient of refractive index. Like all refracting elements, lens performance depends on the wavelength of the refracted light. This wavelength dependent focusing leads to chromatic a

The knowledge concerning electricity consumption, and especially load demand, in Swedish commercial buildings is very limited. The current study deals with methods for electricity consumption indicator development and application of the different methodologies on measured data. Typical load shapes and consumption indicators are developed for four different types of commercial buildings: schools, h

This paper reports on physical limitations on metamaterials in scattering and antenna problems. A dispersion relation for the extinction cross section is derived from the holomorphic properties of the forward scattering dyadic. The result states that for a given volume, there is only a limited amount of scattering and absorption available in the entire frequency range. The dispersion relation is v