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The direct and inverse scattering problems for a plane-stratified viscoelastic medium excited by a transient plane wave of SH or P-SV type are treated. The viscoelastic medium is characterized by two time and space dependent memory functions and a spatially dependent density. The direct and inverse problems are solved by a time-domain wave propagator method that is related to the Green functions t

Lund University, Sweden, is developing a video analysis system for making long-term behavioural studies, primarily in complex urban environments. Road users are detected using the KLT (Kanade-Lucas-Tomasi) interest point tracker. Trajectories are estimated using foreground–background segmentation, whereas speed is estimated using the shape analysis of interest points. The extracted trajectories ar

A new chemical reactor, the Open Plate Reactor (OPR), is being developed by Alfa Laval AB. It has a very flexible configuration with distributed inlet ports, cooling zones and internal sensors. This gives the OPR improved control capabilities compared to standard chemical reactors in addition to better heat transfer capacity. In this paper, we address the relationship between the process design,

A bilinear system model of a continuous tank reactor from a biotechnology application (F. Mandenius et al., 1987) is studied. The concentrations of the substrate sugar and the product ethanol were measured on-line and utilized to control the flow-rate through the fermenter. The system can be integrated analytically making it possible to describe the reachable sets. Limited controllability is found

The direct problem of time dependent electromagnetic scattering in the dispersive sphere is solved by a wave splitting technique. The electric field is expanded in a series involving vector spherical harmonics, leading to a system of wave equations for each term. These systems are reduced to scalar wave equations for each term, which are solved via reflection operators. Some preliminary numerical

Using the optical double resonance and level crossing methods, properties of several excited S , P , and D states in 39 K were studied. The S and D states were populated using stepwise excitation with the first P state as an intermediate level. An rf lamp and a CW dye laser were used in the first and second excitation steps, respectively. The studied P states were populated in the cascade decay of

Nonlinear propagation of electromagnetic waves is an important problem in optics. Often the properties of the nonlinear media are not fully understood. The solution of an inverse problem can provide an aid to that understanding. An inverse transmission problem is posed, it is one of reconstructing the medium parameters, by measurement of a wave that has been propagated through the nonlinear medium

This paper studies regional museum, archives and arts education commissions of the Region of Scania, reformed in 2009, from a policy analysis perspective. It describes the background, design and implementation of the new policy and analyses its effects. The paper gives detailed information on the complexities of policy tool design and implementation, and discusses it in the light of regional gover