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The normal approach to digital control is to sample periodically in time. Using an analog of integration theory we can call this Riemann sampling. Lebesgue sampling or event based sampling is an alternative to Riemann sampling. It means that signals are sampled only when measurements pass certain limits. In this paper it is shown that Lebesgue sampling gives better performance for some simple syst

Using DTT and iodoacetamide as a novel irreversible method to inhibit endogenous violaxanthin de-epoxidase, we found that violaxanthin could be converted into zeaxanthin from both sides of the thylakoid membrane provided that purified violaxanthin de-epoxidase was added. The maximum conversion was the same from both sides of the membrane. Temperature was found to have a strong influence both on th

The max-bisection and min-bisection problems are to find a partition of the vertices of a graph into two equal size subsets that, respectively, maximizes or minimizes the number of edges with endpoints in both subsets. We design the first polynomial time approximation scheme for the max-bisection problem on arbitrary planar graphs solving a long-standing open problem. The method of solution involv

Background: Exhaled breath condensate (EBC) is simple to cottect and as such a non-invasive method that has attracted substantial interest in the last few years. However, several methodological concerns have been raised and it has been difficult to reproduce results between different centres. Because of low concentrations of inflammatory markers, potential loss in the sampling system may have grea

In this paper, a number of challenges, which need to be overcome if multivariate monitoring of wastewater treatment operation is to be successful, are presented. For each challenge, one or several solutions are discussed. The methodologies are illustrated using an example from full-scale wastewater treatment operation. Some guidelines regarding choices of methods and implementation aspects are giv

There is a need for objective and quantitative methods for measuring posture and movement, so that, for instance, exposure-response relationships for work-related musculoskeletal disorders can be established. Inclinometry data have been obtained from triaxial accelerometers based on uniaxial solid-state accelerometers used in conjunction with a computer program to perform co-ordinate transformatio

The utilisation of biofuels is attracting growing support from the European Union and member states as a strategy to tackle climate change, enhance energy security, and contribute to regional development. This paper describes, compares, and analyses the markets for biofuels in Germany and the UK. The introduction of biofuels for transport in these member states provides contrasting pictures, and t

PURPOSE: CT and MR imaging are appropriate modalities for imaging of the liver. Contrast media are used to obtain a greater difference in attenuation and signal intensity, respectively, between normal liver tissue and focal lesions. However, no studies have attempted to determine whether physiological nutritional status of the liver during fasting is of importance for the native signal of normal l

Medical physics education and training requires the use of extensive imaging material and specific explanations. These requirements provide an excellent background for application of e-Learning. The EU projects Consortia EMERALD and EMIT developed five volumes of such materials, now used in 65 countries. EMERALD developed e-Learning materials in three areas of medical physics (X-ray diagnostic rad

This paper presents an application of the Hilbert-Huang transform (HHT) and ensemble correlation for detection of the transient evoked otoacoustic emissions (TEOAEs), and high resolution time-frequency mapping. The HHT provides a powerful tool for nonlinear analysis of nonstationary signals such as TEOAEs. Since the HHT itself does not distinguish between signal and noise it was used with ensemble

Case study is a suitable research methodology for software engineering research since it studies contemporary phenomena in its natural context. However, the understanding of what constitutes a case study varies, and hence the quality of the resulting studies. This paper aims at providing an introduction to case study methodology and guidelines for researchers conducting case studies and readers st

Structure-property relationships of polymers incorporating Lewis acidic boron in their branched chain architecture were investigated as a function of LiClO4 salt concentration. The polymers were synthesised from boron trioxide, and different poly(ethylene glycol)s (PEGs) and monomethyl ether end-capped PEGs. The PEG-boronate ester polymers based on PEGs having molecular weights equal to, or below,

This article proposes nonparametric inference procedures for analyzing microarray gene expression data that are reliable, robust, and simple to implement. They are conceptually transparent and require no special-purpose software. The analysis begins by normalizing gene expression data in a unique way. The resulting adjusted observations consist of gene-treatment interaction terms ( representing di

Surface wave characteristics and radiation efficiency are calculated for a patch antenna with a given current distribution and located on top of an inhomogeneous, isotropic substrate. The substrate is infinite in the lateral directions and inhomogeneous with respect to the height coordinate. The surface waves in the substrate are analysed using the propagator technique and residue calculus. The pr

The paper critically reviews some themes and methods within qualitative research and argues for self-ethnography as an approach to study universities and other settings which the researcher is highly familiar with, and has direct access to. Advantages and disadvantages are discussed. In particular the struggle between utilizing closeness to empirically rich situations and avoid the closure followi