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Reference-based search strategies in systematic reviews

In systematic reviews, the number of articles found by search strings tend to be very large. In order to limit the number of articles to handle manually, we investigate a search strategy based on references between papers. We first identify a “take-off paper” which is the starting point for the search and then we follow the references from that paper. We also investigate “cardinal papers”, i.e. pa

Characterization of Pt/γ-Al2O3 Catalysts Deactivated by Hexamethyldisiloxane

The deactivation of alumina supported platinum and iron catalysts by hexamethyldisiloxane (HMDS) exposure has been investigated. Three catalysts (Pt/Al2O3, Fe/Al2O3 and Fe/Pt/Al2O3) were prepared and the influence of short- and long-term deactivation on the activity for oxidation of ethyl acetate was studied. The catalysts were characterized using BET, ICP-AES, XPS, SEM and CO chemisorption. The d

Transient wave propagation in gyrotropic media

In this paper transient electromagnetic wave propagation in an inhomogeneous, cold plasma is considered. It is assumed that a constant magnetic induction is present and that the plasma is spatially inhomogeneous in the direction of the magnetic induction. Losses in the plasma are modeled with a collision frequency ν. The direct problem, which is to calculate the reflected and transmitted responses

Diode laser spectroscopy in extended wavelength ranges

Diode laser spectroscopy performed in the ultraviolet, visible and infrared spectral regions is presented. The accessible wavelength range for visible and near-infrared diode lasers is extended by the use of sum- and difference-frequency generation. Sum-frequency generation to the ultraviolet spectral region was employed using a blue and a red diode laser. Mercury spectroscopy was demonstrated wi

A highly integrated CMOS direct digital RF quadrature modulator

A highly integrated CMOS direct digital RF quadrature modulator, consisting of two 10-bit linear interpolation current steering digital-to-analog converters (DACs) and two Gilbert cell based mixers, is described. By employing linear interpolation, the attenuation of the DAC's image components is significantly increased, and the reconstruction filter is therefore eliminated. The DAC's differential

Outland, centre, periphery and world systems theories. Some remarks from a Swedish perspective

I started with a rather superficial overview of some of the problems that medieval archaeologists have to face when they try to study marginal areas, marginal in the view of those who are living near the political and economic power on one level or another. We can formulate the problems in centre-periphery models but we have also discussed some kind of world system thinking (which of course is con

Innovation in symbolic industries: the geography and organisation of knowledge sourcing

This paper deals with geographical and organisational patterns of knowledge flows in the media industry of southern Sweden, an industry that is characterised by a strong ‘symbolic’ knowledge base. Aim is to address the question of the local versus the non-local as the prime arena for knowledge exchange, and to examine the organisational patterns of knowledge sourcing with specific attention paid t

Atom-atom correlations in colliding Bose-Einstein condensates

We analyze atom-atom correlations in the s-wave scattering halo of two colliding condensates. By developing a simple perturbative approach, we obtain explicit analytic results for the collinear (CL) and back-to-back (BB) correlations corresponding to realistic density profiles of the colliding condensates with interactions. The results in the short-time limit are in agreement with the first-princi

Computationally Efficient Robust Widely Linear Beamforming for Improper Non-Stationary Signals

In this work, we introduce a computationally efficient Kalman-filter based implementation of the robust widely linear (WL) minimum variance distortionless response (MVDR) beamformer. The beamformer is able to achieve the same performance as the recently derived robust WL MVDR beamformer, but avoids the computationally burdensome solution based on a second order cone programming (SOCP), and exploit