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An experimental approach to verify the forward scattering sum rule for periodic structures is presented. This approach allows an upper bound on the total cross section integrated over a bandwidth from a simple static problem to be found. Based on energy conservation, the optical theorem is used to construct a relation between the total cross section and the forward scattering of periodic structure

We compute the Cramér-Rao lower bounds for determination of isotropic permittivity and permeability in slabs using scattering data such as reflection and transmission coefficients. Assuming only the fundamental mode is propagating in the slab, the results are formally the same regardless if the slab is in free space, or inside a rectangular or coaxial waveguide. The bounds depend only on signal qu

High-speed communication using the copper network, originally installed for telephony, is one of the dominant Internet access techniques. Several variants of a technology referred to as digital subscriber line (xDSL) have been developed, standardized and installed during the last two decades. Essentially, xDSL achieves high rates by exploiting wide bands of the copper cable channel. The shorter th

Popular Abstract in Swedish Hantering av risker i företag och organisationer har haft en lång och komplicerad historia. På åttiotalet, och i början av nittiotalet, var uppfattningen att om en olycka inträffade i en organisation, som påstods vara nära nog perfekt, måste det bero på ”den mänskliga faktorn”, dvs. att en eller flera medarbetare inte gjorde som de borde ha gjort. Orsakerna till olyckaIntroduction Risk management in enterprises, organisations and companies has had a long and complicated history. During the eighties, and at least during the beginning of the nineties, the notion concerning risk management was that if an accident happened in an otherwise perfect system it was due to the human operator in some way being the cause of the error. The cause for the accidents was desc

Minor structural changes on the surface of proteins can have tremendous impact on their biological properties. When producing therapeutic proteins it is therefore important to verify that the generated protein is the desired one. Small variations such as glycosylations or amino acid substitutions can mean the difference between a functional, defective or even toxic product. This thesis describes

In this thesis, we draw inspiration from both classical system identification and modern machine learning in order to solve estimation problems for real-world, physical systems. The main approach to estimation and learning adopted is optimization based. Concepts such as regularization will be utilized for encoding of prior knowledge and basis-function expansions will be used to add nonlinear model

Devices based on molecular motor-driven cytoskeletal filaments, e.g., actin filaments, have been developed both for biosensing and biocomputational applications. Commonly, these devices require nanoscaled tracks for guidance of the actin filaments which has limited the patterning technique to electron beam lithography. Thus, large scale systems become intractable to fabricate at a high throughput

Coherent phenomena have been widely suggested to play a role in efficient photosynthetic light harvesting and charge separation processes. To substantiate these ideas, separation of intramolecular vibrational coherences from purely electronic or mixed vibronic coherences is essential. To this end, polarization-controlled two-dimensional electronic spectroscopy has been shown to provide an effectiv

Ichthyosaurs are extinct marine reptiles that display a notable external similarity to modern toothed whales. Here we show that this resemblance is more than skin deep. We apply a multidisciplinary experimental approach to characterize the cellular and molecular composition of integumental tissues in an exceptionally preserved specimen of the Early Jurassic ichthyosaur Stenopterygius. Our analyses

Pairwise comparison of sound and radio signals can be used to estimate the distance between two units that send and receive signals. In a similar way it is possible to estimate differences of distances by correlating two received signals. There are essentially two groups of such methods, namely methods that are robust to noise and reverberation, but give limited precision and sub-sample refinement

Background Both internet-based cognitive-behavioural therapy (ICBT) and physical exercise are alternatives to treatment as usual (TAU) in managing mild to moderate depression in primary care.Aims To determine the cost-effectiveness of ICBT and physical exercise compared with TAU in primary care.Method Economic evaluation of a randomised controlled trial (N = 945) in Sweden. Costs were estimated by

The response of a coupled atmosphere-ocean general circulation model to insolation representative of 6000 years ago has been studied with a set of 1000-year quasi-equilibrium simulations. Comparison with similar experiments with an uncoupled atmosphere general circulation model demonstrates the importance of an interactive ocean for the climate signal. The model simulates an intensification of the