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In the context of transient processes in power system measurements, a sampled signal is analyzed with respect to electro-magnetic influences. These are most likely superposed sinusoids that can be found next to the fundamental system sinusoid. However, such signal is not stationary, i.e. has a varying model order which means that temporary and exponentially damped sinusoids appear eventually. In our previous work, the exponential damping was only considered indirectly but not explicitly incorporated in the signal model used. Regarding the amplitude estimation, this led to inaccuracies since the amplitude was incorrectly assumed constant within a window of samples. In this paper, we use ESPRIT's ability to also estimate a parameter of exponential damping, improve the corresponding signal model, advance the amplitude estimation algorithm and back projection algorithm. Especially short-term signal components can be tracked far more precise.

In the context of parameter estimation, subspace-based methods like ESPRIT have become common. They require a subspace separation e.g. based on eigenvalue/-vector decomposition. In time-varying environments, this can be done by subspace trackers. One class of these is based on the PAST algorithm. Our non-linear parameter estimation algorithm DaPT builds on-top of the ESPRIT algorithm. Evaluation of the different variants of the PAST algorithm shows which variant of the PAST algorithm is worthwhile in the context of frequency estimation.

The use of Information and Communication Technology (ICT)-based power system applications increases continually which poses new engineering challenges regarding the development, validation and management of both - the applications and the intertwined infrastructures. In this paper the need for a joint analysis of power and ICT systems for evaluating smart grid applications is discussed and a systematic validation approach is proposed. After reviewing state of the art validation techniques, a newly developed Wide-Area Monitoring, Protection and Control (WAMPAC) system is introduced. Its extensive use of wide-area communication and the combination of centralized and decentralized decision making stress the complexity of such a cyber-physical system, where the interdependency between the power system and the ICT domains are challenging to validate. Deduced from these requirements, a validation concept is proposed that comprises (i) the usage of a comprehensive smart grid reference model, (ii) a systematic and objectively verifiable generation of scenarios, and (iii) a single and multi-domain validation process using analytical, simulative and experimental techniques. For the latter, a composition of analyses using co-simulation, Hardware-in-the-Loop (HiL) simulations and an empirical test bed is outlined.

A 54-year-old man was admitted to hospital because of chronic right-sided heart failure. Echocardiography revealed dilatation of all chambers of the heart. Cardiac catheterization showed high-output heart failure due to left-to-right shunt caused by a congenital fistula between the right iliac artery and vein. The fistula was closed by percutaneous implantation of a covered stent. 15 months later, the patient denied any cardiac complaint. On echocardiography, the size of all chambers had almost normalized, cardiac catheterization proved a normal cardiac output. By angiography and oximetry, neither a residual nor a relapsing shunt were seen.

In modern power transmission systems, monitoring of transient processes becomes more important. Analyzing a transient process is hard since the process is not only transforming from one steady state into another, but it also includes event-driven oscillations from LC-circuits within the net. The number of such oscillations is unknown and not constant. Furthermore, the oscillations can have a small amplitude. The knowledge of such oscillations can help understanding what happens where in the net. To estimate these oscillations, we present a signal processing method based on subspace estimation and history-based data ranking. It enables the estimation of an a-priori unknown number of oscillations and so the rank, although their amplitude might be small compared to dominating components.

Hamming networks have been investigated to develop IR spectral search systems. The resulting system is able to identify spectra of mixtures with high fault tolerance. Hamming networks were tested with a set of about 1000 spectra of pharmaceutical components. The main components of mixtures are identified correctly in most cases. Less concentrated components are mostly to be found in a hit of the 10 best matching substances.

Summary Modern geophysical interpretation requires an interdisciplinary approach and software capable of handling multiple data like seismic, FTG gravity, magnetic and magnetotelluric. We introduce the new IGMAS+ ("Interactive Geophysical Modeling Application System") geo-modeling software for realistic 3D FTG and magnetic modeling. The software is grid capable and allows extreme fast distributed calculations on normal hardware such as a network of PCs. An outlook is given towards semantic constraints generated by ontology based search technologies. A show case for CCS (carbon capture storage) will be presented. Finally the interlink between data modeling and text mining will be discussed.

Three-dimensional (3D) interactive modeling with the IGMAS software provides means for integrated processing and interpretation of geoid, gravity and magnetic fields and their gradients (full tensor), yielding improved geological interpretation. IGMAS fully three-dimensional models are constructed using triangulated polyhedra and/or triangulated grids, to which constant density and/or induced and remanent susceptibility are assigned. Interactive modifications of model parameters (geometry, density, susceptibility, magnetization), access to the numerical modeling process, and direct visualization of both calculated and measured fields of gravity and magnetics, enable the interpreter to design the model as realistically as possible. IGMAS allows easy integration of constraining data into interactive modeling processes, visualization and combination of geodata with density/susceptibility models. These visual overlays of different 2D and 3D datasets enables quantitative comparison and adjustment and results in models that are constrained by as much independently derived information as possible.

We would like to thank V. I. Starostenko for his interest in our paper and his historical remarks on the development of 3‐D modeling formulas in gravity and magnetics. The main objective of our paper was to publish a user‐friendly fast interpretation tool for 3‐D modeling including interactive computer graphics. Therefore, it does not deal with an extended derivation of the formulas used in potential field theory.

After inducing experimentally a stenosis of the aorta abdominalis in rabbits, the mitochondria of the aortic endothelium were fluorescence-optically demonstrated, and quantitatively investigated above as well as below the stenosis. The changes in the number of the mitochondria are proportional to the values of blood pressure, and are discussed in relation to changes in the shape of the endothelial cells.