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Information about the 35th IEEE International Conference on Plasma Science (ICOPS 2008) held at the Congress Center in Karlsruhe, Germany on June 15-19, 2008 is presented. The technical program of the conference includes basic processes in fully and partially ionized plasmas, microwave generation and plasma interactions, and charged particle beams and sources. It also includes high energy density plasmas applications, plasma diagnostics, and pulsed power other plasma applications.

The article offers information on the joint conference of 4th Euro-Asian Pulsed Power Conference (EAPPC 2012) and 19th International Conference on High-Power Particle Beams (BEAMS 2012) to be held in Germany from September 30-October 4, 2012.

The joint conference of 4th Euro-Asian Pulsed Power Conference (EAPPC 2012) and 19th International Conference on High-Power Particle Beams (BEAMS 2012) will be held on Sep. 30 - Oct. 4, 2012, in Karlsruhe, Germany (http://www.eappc-beams2012.org). This conference will reflect the most recent developments on pulsed power technology and high-power particle beam physics and applications. The objective of this Special Issue is to bring the most up-to-date developments reported at EAPPC/BEAMS 2012 to the readership of IEEE Transactions on Plasma Science. Although the conference will publish its own Proceedings, this Special Issue will be dedicated to manuscripts that are substantially revised and lengthened from those of the Proceedings. These manuscripts will undergo standard peer-review process typical for all IEEE Transactions and Journals. The manuscript submission deadline is December 31, 2012. This Special Issue IS open to, but not limited to, all attendees of EAPPC/BEAMS 2012. [ABSTRACT FROM PUBLISHER]

Terrestrial broadcast has traditionally targeted TV receivers in the home. But today’s most popular screens are those of SmartPhones and Tablet PCs. (Painful) Experience has shown that in order to reach those gadgets, IEEE- and 3GPP-specified solutions are required. Starting with TOoL+, the authors have proposed bridges between traditional broadcast and today’s wireless connectivity. Within the set of specifications of 3GPP such bridges named MBS, MBMS, and FeMBMS now exist – with limited acceptance by cellular network operators so far. The rapidly growing number of popular data services to SmartPhones, connected cars, etc., and 5G New Radio may change this in the future. Therefore, this paper presents a broadcast extension of today’s 5G New Radio supporting the implementation of High Tower High Power/Medium Power Medium Tower networks overlaying cellular networks. The extension was implemented using software defined radio and tested in a real-world field trial in Germany. [ABSTRACT FROM AUTHOR]

The new characteristics and phenomena of hybrid AC/DC transmission grids challenge the conventional protection concepts. In hybrid AC/DC overhead line systems, AC and DC systems are located on the same support structure. As a result, electromagnetic and galvanic interactions between the AC- and the DC-line influence the AC-protection and the DC-control in a novel and complex way. This paper presents key findings and solutions from a current 400-kV-hybrid AC/DC overhead line project in Germany. The focus is on AC/DC intersystem faults, i.e. galvanic contact between DC and AC systems. Fault detection and fault response of the AC-protection and the DC-control as well as a proper AC/DC protection coordination are discussed. The paper illustrates the challenges of a secure and dependable fault clearing and indicates solution methods. The findings of this paper are based on EMT simulations with detailed PSCAD-models of the hybrid AC/DC overhead line and the VSC-converters. Laboratory protection tests have been conducted and confirmed the results. [ABSTRACT FROM AUTHOR]

In this paper five different flexibility options are analysed from a techno-economic perspective as alternatives to traditional grid expansion for a specific distribution grid in Germany. The options are: two reactive power control strategies with photovoltaic inverters (as a function of the power feed-in, or of the voltage at the connection point), one residential and two large scale battery storage applications (primary control reserve with autonomous reactive power control or self consumption maximisation strategy with autonomous reactive power control). For the pilot grid located in Southern Germany a photovoltaic expansion pathway is determined. The main goal of this work is to quantify the grid expansion actions that can be avoided by applying these five flexibility options for the assumed expansion pathway, focusing on large scale battery storages. It is shown that the five flexibility options increase the hosting capacity for PV systems, compared to a scenario without, by up to 45%. Furthermore, the results of the economic assessment indicate that the analysed flexibility options might be a viable alternative to traditional grid expansion as all of them show a cost reduction potential for the pilot region. These results could encourage DSOs to consider the integration of additional PV and battery storage systems not as a problem which triggers grid expansion, but as part of the solution reducing future grid expansion costs. [ABSTRACT FROM AUTHOR]

The eight papers in this special section were presented at the 27th International Conference on Data Engineering (ICDE 2011) that was held in Hannover, Germany on 11-16 April 2011. [ABSTRACT FROM AUTHOR]

In this paper, a detailed mathematical model of the diabatic compressed air energy storage (CAES) system and a simplified version are proposed, considering independent generators/motors as interfaces with the grid. The models can be used for power system steady-state and dynamic analyses. The models include those of the compressor, synchronous motor, cavern, turbine, synchronous generator, and associated controls. The configuration and parameters of the proposed models are based on the existing bulk CAES facilities of Huntorf, Germany. The models and performance of the CAES system are first evaluated with step responses, and then examined when providing frequency regulation in a test power system with high penetration of wind generation, comparing them with existing models of CAES systems. The simulation results confirm that the dynamic responses of the detailed and simplified CAES models are similar, and demonstrate that the simultaneous charging and discharging can significantly contribute to reduce the frequency deviation of the system from the variability of the wind farm power. [ABSTRACT FROM AUTHOR]

The nanonewton force facility of Physikalisch-Technische Bundesanstalt (PTB), Germany, has been significantly improved. We demonstrate the possibility of using the facility as a calibration device that can accurately determine spring constants of soft cantilevers ($k < 0.1\,\,\text {N}\cdot \text {m}^{-1}$) with traceability to the SI units. This paper is described the possibility of increasing the range of the measured forces to 1 mN. We demonstrate the possibility of using PTB’s nanonewton force facility to accurately determine and compensate for the contact potential difference. To measure the contact potential difference and at the same time the distance between a force sensor and a measured object, a new three-voltage method was developed. For a so-called “plan–plan geometry,” the results of measuring the contact potential difference and the distance in vacuum are presented. A new method of adjusting the parallelism of the plates is also presented. The method used to measure the negative light pressure (light-induced force), which had previously been only theoretically predicted, and the first results of the measurement are presented as well. [ABSTRACT FROM AUTHOR]

Tomographic synthetic aperture radar (TomoSAR) inversion of urban areas is an inherently sparse reconstruction problem and, hence, can be solved using compressive sensing (CS) algorithms. This paper proposes solutions for two notorious problems in this field. First, TomoSAR requires a high number of data sets, which makes the technique expensive. However, it can be shown that the number of acquisitions and the signal-to-noise ratio (SNR) can be traded off against each other, because it is asymptotically only the product of the number of acquisitions and SNR that determines the reconstruction quality. We propose to increase SNR by integrating nonlocal (NL) estimation into the inversion and show that a reasonable reconstruction of buildings from only seven interferograms is feasible. Second, CS-based inversion is computationally expensive and therefore, barely suitable for large-scale applications. We introduce a new fast and accurate algorithm for solving the NL L1-L2-minimization problem, central to CS-based reconstruction algorithms. The applicability of the algorithm is demonstrated using simulated data and TerraSAR-X high-resolution spotlight images over an area in Munich, Germany. [ABSTRACT FROM AUTHOR]

The second generation digital video broadcasting system for terrestrial broadcasting (DVB-T2) was designed using a toolbox concept. Compared with its predecessor DVB-T, the new standard introduces many new algorithms and allows for a more flexible parameter configuration. The parameters can be perfectly optimized for each reception scenario, ranging from stationary reception with roof-top aerials, up to portable or mobile reception. However, all countries that have already introduced DVB-T2 mainly focus on stationary reception. In contrast, stationary reception is no relevant option for a potential introduction of DVB-T2 in Germany. Instead, a potential roll-out would focus on the benefits of terrestrial broadcasting compared to satellite and cable, i.e., mobility. Within an extensive field trial in northern Germany, the performance of the different parameter configurations and new algorithms offered by DVB-T2 were analyzed in detail, e.g., multiple physical layer pipes, rotated constellations, and multiple-input single-output. This paper presents the trial network and the obtained measurement results, which are based on thousands of individual measurements. Moreover, the document gives recommendations for an optimal parameter configuration. [ABSTRACT FROM AUTHOR]

The Super-FRS (Super FRagment Separator) is a part of FAIR (Facility for Antiproton and Ion Research), which will be constructed at GSI, Germany by 17 countries. The Super-FRS comprises 24 superferric dipole magnets. The 2D and 3D magnetic field simulations of the prototype magnet are described in this paper. A passive trim slot and four chamfered removable poles are used to satisfy the required field homogeneity which is better than ±3 x 10-4 at 1.6 T, 0.8 T and 0.16 T in a wide elliptical useable aperture of 380 mm 140 mm. Measurement results at various field levels are shown in this paper as well. It can be seen from the comparison of calculation and measurement results that the magnetic designs of the magnet fulfils the requirements. [ABSTRACT FROM AUTHOR]

In this paper, we study the effect of the elevation of incoming multipaths at a multielement antenna receiver by using a novel 3-D approach. It is shown that under a more general 3-D angle-of-arrival (AoA) model, namely, the Fisher-Bingham five-parameter (FB5) distribution, the spatial fading correlation (SFC) that is experienced between the adjacent antenna array elements decreases as the elevation increases. The FB5 distribution does not have a known series expansion, and therefore, the defining SFC integral can only numerically be evaluated. The proposed SFC function is further extended to capture the effect of multiple clusters of scatterers in the propagation channel. We, therefore, propose a mixture SFC function that is scaled according to the probability that each cluster contributes to the channel. The parameters of the individual components that constitute the mixture are estimated by using a soft expectation maximization (soft-EM) algorithm. The results indicate that the proposed model fits well with the data obtained from a multiple-input-multiple-output (MIMO) measurement campaign in the city of Ilmenau, Germany. [ABSTRACT FROM AUTHOR]

A hybrid mobile communication network as considered in this paper consists of a point-to-point network (UMTS) and a point-to-multipoint network (DVB-H). The benefit of combining these two networks is an optimized transfer of data by collecting several user requests for a single response via the broadcast network. Thus, capacity can be saved, UMTS cells can be unloaded and the mean response time of the system can be reduced. Besides these advantages, hybrid networks can be applied to decrease electromagnetic exposure, especially at hot spot areas. In this paper, it is analysed how the hybrid network structure influences the electromagnetic exposure. Therefore, different scenarios have been developed consisting of different user behavior and different network structures. In order to evaluate the grade of exposure, criteria have been defined. These criteria have been used for comparing a hybrid network with a single UMTS network in terms of electromagnetic exposure. The results are shown for the different network structures and network configurations. [ABSTRACT FROM AUTHOR]

In this paper, we present the currents, which have been measured since 2008 at the new top structure of the Peissenberg Tower, Germany, and the associated electric fields in a distance of about 180 m from the tower. The study comprises 17 negative lightning, which contained 44 subsequent return strokes, 108 initial continuous current (ICC)-pulses, and 26 M-components. The analysis, based on the current waveform, revealed three different types for both the M-component current and the ICC-pulse. The impulsive current of type 1 has a more or less symmetrical wave shape. For this type, the electric field occurred on average 15.7 μs prior to the current pulse. The impulsive current of type 2 has a bipolar wave shape with current reversal. The impulsive current of type 3 has a wave shape, which exhibits a fast rise to peak and a much longer decay to low current values. For all types of impulsive currents (return strokes, ICC-pulses, and M-components), the electric field exhibits a first field change (ΔE1) followed by a second field change (ΔE2) of opposite polarity. For the ICC-pulses and M-component currents of types 1 and 3, the first field change (ΔE1) has typically an initial slow-rising section, which is followed by a fast-rising section. The transition point was time-correlated with the onset of the current. The transition point was at about ΔE1/3 for type 1 and at about ΔE1/2 for type 3. For type 2, the onset of the current pulse occurred during the second field change (ΔE2) of opposite polarity. Similar to type 1 and 3 pulses, the slow-rising electric field changed into a fast-rising electric field. The transition point for type 2 pulse was at about ΔE2/3. From the 44 subsequent return strokes, 8 of them contained one negative M-component of type 1. In that case, the M-component current was extremely strong. The arithmetic mean (AM) was 8.5 kA (GM: 5.4 kA) for the peak current and 747.8 mC (GM: 614.0 mC) for the transferred charge. The return stroke was also very strong, with an AM of 16.7 kA for the peak current (GM: 15.0 kA). In comparison, the AM was 10.4 kA (GM: 8.3 kA) considering all subsequent return strokes. [ABSTRACT FROM AUTHOR]

An updating study concerning the analysis and modeling of the European Energy Exchange power market in Germany is urgently called for due to the dramatic transformations of the market in recent years. Based on careful data research, this paper provides a consolidated and detailed view concerning the development of the market and its mechanisms. This paper proposes a new analytical model of the merit order curve of the market. The model is designed to capture the occurrences of negative prices. It considers fuel prices and CO2 prices, and by taking into account the structural changes of the market such as the increasing energy in-feed from renewable sources and the moratorium of nuclear power plants in Germany, the model is robust to these changes of market fundamentals. The proposed merit-order-curve model constitutes a critical component in realistic fundamental models for the European Energy Exchange power market. [ABSTRACT FROM PUBLISHER]

Structured canopies can show pronounced directional effects which influence land surface temperature (LST) estimates from thermal infrared satellite data. The effects depend on illumination and viewing geometries, because changes in these two geometries effectively cause the sensor to “see” different fractions of the canopy and the “background” surface (bare soil or low vegetation). Furthermore, parts of these two components will be in shadow, depending on the specific geometry of the canopy and its structure. This paper investigates these directional effects for a specific savanna site in West Africa and extends the findings to areas with denser tree crown cover. This is achieved by modeling the combined effects of the structured surface with a geometric optics model. The model assumes that the surface consists of four components: shaded and sunlit tree canopies and shaded and sunlit backgrounds. The brightness temperatures of these four surface components are provided by in situ measurements at the validation site, and emissivities are taken from the Land Surface Analysis Satellite Applications Facility (LSA-SAF) project. The LST modeling is performed for the geometry of the geostationary Meteosat Second Generation and for nadir geometry. Analyses of the temperature differences between the LST estimates for the two geometries show that, in many cases, the directional effects exceed 1 ^\circ\C within a day and that the timing and the sign of the effects change with season. Directional errors due to structured canopies are currently not considered in error estimates of operationally available LST products, e.g., the LSA-SAF LST product or the Moderate Resolution Imaging Spectroradiometer (MODIS) LST/emissivity products. [ABSTRACT FROM AUTHOR]

Wendelstein 7-X (W7-X) is a superconducting stellarator under construction at the Max-Planck-Institute for Plasma Physics in Greifswald, Germany. The magnet system consists of 70 superconducting coils providing magnetic confinement-fields. Before assembly every coil had to pass an acceptance test at the French partner-institute CEA, Saclay, to examine its performance on leak tightness, high voltage strength, ampacity, and hydraulic flow at cryogenic conditions. The testing procedure was mandatory, as access for maintenance or repair after installation will not be viable. Testing followed a well specified routine including tests in warm conditions, during cool down, in cold conditions, during warm up and at last in warm conditions. Measurement was obtained firstly by the facility's instrumentation and secondly by the coil-casing's instrumentation. The received data was transmitted to different ASCII-files for each gauge. To record testing in detail, a meta-document was edited, which follows in its structure the routine mentioned above. Accordingly, the main distinctive functions of the coil during testing are recorded in so called test reports, while deviations from given thresholds and parameters are described in non conformity reports. During testing, organizational and technical challenges had to be mastered and the test program was regularly updated to meet technical improvements, manufacturing requirements and revised assembly schedules. This paper will present the acceptance test program, its development and the gained experiences. [ABSTRACT FROM AUTHOR]

In today's teaching and learning approaches for first-semester students, practical courses more and more often complement traditional theoretical lectures. This practical element allows an early insight into the real world of engineering, augments student motivation, and enables students to acquire soft skills early. This paper describes a new freshman introduction course into practical engineering, which has been established within the Bachelor of Science curriculum of Electrical Engineering and Information Technology of RWTH Aachen University, Germany. The course is organized as an eight-day, full-time block laboratory for over 300 freshman students, who were supervised by more than 60 tutors from 23 institutes of the Electrical Engineering Department. Based on a threefold learning concept comprising mathematical methods, MATLAB programming, and practical engineering, the students were required to transfer mathematical basics to algorithms in MATLAB in order to control LEGO Mindstorms robots. Toward this end, a new toolbox, called the "RWTH--Mindstorms NXT Toolbox," was developed, which enables the robots to be controlled remotely via MATLAB from a host computer. This paper describes how the laboratory course is organized and how it induces students to think as actual engineers would in solving real-world tasks with limited resources. Evaluation results show that the project improves the students' MATLAB programming skills, enhances motivation, and enables a peer learning process. [ABSTRACT FROM AUTHOR]

We present the first analysis of surface current fields derived from TerraSAR-X along-track interferometric synthetic aperture radar (along-track InSAR, ATI) data. The images were acquired over the mouth of the Elbe river (Germany) during six satellite overpasses in spring and summer 2008, using the experimental "aperture switching" mode of TerraSAR-X. In this mode, the phased-array synthetic aperture radar (SAR) antenna is split into two halves for receiving, but in contrast to the "dual receive antenna" mode, which uses two independent receivers in parallel, a single receiver is multiplexed to process signals from the two antenna halves in an alternating manner at a doubled pulse repetition frequency. The effective ATI baseline is on the order of 0.8 m. The SAR/ATI raw data processing is described in another paper in this issue. This paper focuses on the conversion of the basic interferograms into line-of-sight surface current fields, which includes an elimination of ship signatures, identification, and correction (as far as possible) of imaging artifacts, additional filtering and smoothing, and a subtraction of contributions of wave motions to detected velocities according to a theoretical model. We evaluate the quality of the results by comparison with current fields from a numerical flow model and with available in situ data. The ATI performance of TerraSAR-X is found to be basically consistent with theoretical expectations. After applying the same data processing algorithms to all six images, mean differences between TerraSAR-X-derived currents and reference currents in our main test area range from -0.11 to +0.08 m/s in five of the six cases with one outlier at +0.42 m/s. The spatial current variations within the TerraSAR-X-derived current fields are consistent with the model in three cases, but unrealistically strong variations across the images are found in the other three cases. We attribute this to shortcomings of our preliminary raw data processing algorithms, which can probably be fixed after some more detailed analysis and testing. The results obtained so far encourage us to believe that our internal performance goal of a typical current measuring accuracy of 0.1 m/s at an effective spatial resolution better than 1 km can be met. [ABSTRACT FROM AUTHOR]

Two Series-Connected Hybrid (SCH) magnets are under development at the National High Magnetic Field Laboratory. The first SCH is for the Helmholtz Centre Berlin (HZB) in Germany. The HZB SCH will be a horizontal bore, 30 T magnet and will be used for neutron scattering experiments. The second SCH is for the National High Magnetic Field Laboratory (NHMFL) in Tallahassee, FL. The NHMFL SCH will be a vertical bore, 36 T magnet. Both SCH Magnets combine a set of resistive Florida-Bitter coils with a superconducting outsert coil constructed of cable-in-conduit conductor (CICC). The two SCH magnets are designed for various operating scenarios including those with multiple ramp cycles at various rates. Both of the superconducting magnets are forced flow cooled with supercritical helium at 4.5 K. A standard refrigerator with a capacity of about 150-200 W at 4.5 K will be used to supply the cooling power and the forced mass flow rate. The cryogenic system of the SCH magnet consists of a helium refrigerator, a valve box with subcooler, a magnet cryostat and cryolines. In this paper, the design of the cryogenic system is described. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the vibrations in a new tram model (the "Combino Plus") developed by Siemens Company, Germany, which was recently launched on a main Budapest road, and in an older tram model withdrawn from the same line. Comparative measurements were made from terminal to terminal (18 sections). The results of this investigation gave us information about the advances made in relation to the vibrational characteristics of trams. This paper summarizes literature concerning the physiological effects of continuous vibration exposures, as well as the standard ISO 2631, to clarify the relevance of the topic and to draw attention to the recorded parameters of the new "Combino Plus" tram. The new "Combino Plus" tram successfully absorbs the vibrations originating from the roughness of the tram rail. This tram produces significantly less vibration for passengers and drivers than the older model tram withdrawn from the main road traffic. The new Combino Plus satisfies the ergonomic requirements and ensures favorable working conditions. [ABSTRACT FROM AUTHOR]

The upgrade of JT-60U to JT-60 Super Advanced (JT-60SA), a fully superconducting tokamak, will be performed in the framework of the Broader Approach (BA) agreement between Europe (EU) and Japan. In particular, the Toroidal Field (TF) system, which includes 18 coils, is foreseen to be procured by France, Italy and Germany. This work covers activities from design and manufacturing to shipping to Japan. The present paper is mainly devoted to the analyses that lead to the conductor design and to the technical specifications of the joints for the JT-60SA TF coils. The conductor geometry is described, which is derived from Cable-In-Conduit concept and adapted to the actual JT-60SA tokamak operating conditions, principally the ITER-like scenario. The reported simulations and calculations are particularly dealing with the stability analysis and the power deposition during normal and off-normal conditions (AC losses, nuclear heating). The final conductor solution was selected through a trade-off between scientific approach and industrial technical orientation. Besides, the TF system connections layout is shown, derived from the industrially assessed twin-box concept, together with the associated thermo-hydraulic calculations ensuring a proper temperature margin. [ABSTRACT FROM AUTHOR]

Subject matter of this paper is the analysis of the total of six upward positive lightning initiated from the Peissenberg Tower, Germany. All of them occurred during the cold season from February to April in the years 1997 to 1999. Three of them were initiated without nearby preceding lightning activity (called “self-initiated” upward lightning) and the other three occurred during nearby lightning activity (called “other-triggered” up-ward lightning). The analysis suggests that the other-triggered upward lightning is a downward lightning involving a relatively long upward connecting leader. The first current component, however, was different from the current of a first return stroke of a positive cloud-to-ground flash. On average, the duration was 15.7 ms, the maximum was 4.37 kA, and the charge was 13.3 C. Due to the long duration and the relatively low current, the first current component is more consistent with the initial continuous current (ICC) of an upward lightning. The initial period of the ICC exhibits a slowly rising portion lasting about 1 ms. During that period, the ICC was superimposed by weak current pulses. The arithmetic means of the pulse peak and the pulse duration were 0.49 kA and 9.6 μs, respectively. The average leader velocity was \bf \bf 2.3 \, \bm \times \,\bf 10^\bf 5 m/s and the average leader charge density was \bf 1.02 \, \bf \times\, \bf 10^\bf -3 C/m. Much stronger current pulses were observed after that initial period. Then, the arithmetic means were 5.3 kA for the pulse peak and 46.6 μs for the pulse duration. The ICC of the self-initiated upward lightning did not exhibit such an initial slowly rising portion with weak superimposed current pulses. The ICC immediately increased to several kilo-amperes involving strong current pulsation. For the ICC, the arithmetic means were 58 ms for the duration, 6.4 kA for the maximum, and 105 C for the charge. For the current pulses, the arithmetic means were 5.7 kA for the pulse peak and 19 μs for the pulse duration. The leader charge density was estimated to be up to several 10 mC/m. [ABSTRACT FROM PUBLISHER]

This paper analyzes the slow-varying electric fields and the associated currents of a total of 35 negative upward lightning initiated by the Peissenberg tower, Germany. Thirty-four of which were from winter upward lightning and only one from summer upward lightning. It appears that all of the winter upward lightning were initiated without nearby preceding lightning activity (called “self-initiated” lightning) and only the summer lightning was triggered by nearby lightning activity (called “other-triggered” lightning). The slow-varying electric fields of the winter upward lightning showed a fast rise characterized by the 10–90% risetime, with an arithmetic mean of 13.8 ms. After attaining the maximum, the electric field turned into a slow decay being characterized by the time on half value which was evaluated to having the arithmetic mean of 441 ms. Transported charges to ground were on average 44.8 C and on maximum 165 C. The maximum value of the electric field was 39.9 kV/m on average, with the highest value being 64.5 kV/m. For the electric fields, higher values were prevented by recovery effects such as the corona from objects at ground and the redistribution of the charge in the thundercloud. Due to these effects, no or only weak correlations were found between the 10–90% risetime, the time on half value, the charge, and the maximum of the electric field. From additional measurements with a field mill, it was found that the electric field recovers to the starting level within some seconds. [ABSTRACT FROM PUBLISHER]

The European Space Agency's Soil Moisture and Ocean Salinity (SMOS) satellite was launched in November 2009 and delivers now brightness temperature and soil moisture products over terrestrial areas on a regular three-day basis. In 2010, several airborne campaigns were conducted to validate the SMOS products with microwave emission radiometers at L-band (1.4 GHz). In this paper, we present results from measurements performed in the Rur and Erft catchments in May and June 2010. The measurement sites were situated in the very west of Germany close to the borders to Belgium and The Netherlands. We developed an approach to validate spatial and temporal SMOS brightness temperature products. An area-wide brightness temperature reference was generated by using an area-wide modeling of top soil moisture and soil temperature with the WaSiM-ETH model and radiative transfer calculation based on the L-band Microwave Emission of the Biosphere model. Measurements of the airborne L-band sensors EMIRAD and HUT-2D on-board a Skyvan aircraft as well as ground-based mobile measurements performed with the truck mounted JÜLBARA L-band radiometer were analyzed for calibration of the simulated brightness temperature reference. Radiative transfer parameters were estimated by a data assimilation approach. By this versatile reference data set, it is possible to validate the spaceborne brightness temperature and soil moisture data obtained from SMOS. However, comparisons with SMOS observations for the campaign period indicate severe differences between simulated and observed SMOS data. [ABSTRACT FROM PUBLISHER]

This paper addresses the question of how projects are organized and how these management structures impact project success. Despite its widely accepted managerial importance, empirical studies could not provide significant evidence of a relationship between implemented management structures and project success. A major problem in finding meaningful empirical evidence is the conceptualization of the structure measure, which is derived from a typologist's perspective. In this study, we follow the taxonomists' perspective and empirically develop an alternative taxonomy of project management structures. We empirically compare both approaches, by using two different samples, collected in the United States and Germany, including together over 600 projects. Our empirical findings show that the validity of the widely accepted project organization typology is in question. The use of cluster analyses reveals an alternative taxonomy that encompasses five structural types, differentiated by the entities managing them: project coordinator, supervised project coordinator, autonomous project manager, supervised project manager, and autonomous functional project manager. The results strongly support the widely accepted proposition of a relationship between project organization and project success. The emerging taxonomy of project organization configurations enriches the theoretical and conceptual discussions of organizing projects and unravels the multiple aspects involved in organizing the execution of projects. [ABSTRACT FROM AUTHOR]

The next step in the Wendelstein stellarator line is the large superconducting device Wendelstein 7-X (W7-X), which is currently under construction in Greifswald. Steady-state operation is an intrinsic feature of stellarators, and one key element of the W7-X mission is to demonstrate steady-state operation at reactor-relevant plasma conditions, as required for an economic fusion reactor. Such steady-state operation requires development of special technologies to be discussed in this paper. [ABSTRACT FROM AUTHOR]

Experimental airborne synthetic aperture radar (SAR) systems achieve spatial resolutions of approximately 10 cm, whereas the new spaceborne very high spatial resolution (VHR) SAR sensors onboard the TerraSAR-X and COSMO-SkyMed satellites achieve spatial resolutions down to 1 m. In VHR SAR data, features fromindividual urban structures (i.e., buildings) can be identified by their characteristic settings in urban settlement patterns. In this paper, we present a novel concept for the height estimation of generic man-made structures from single detected SAR data. The proposed approach is based on the definition of a hypothesis on the height of the building and on the simulation of a SAR image for testing that hypothesis. A matching procedure is applied between the estimated and the actual SAR image in order to test the height hypothesis. The process is iterated for different height assumptions until the matching function is optimized, and thus, the building height is estimated. The efficiency of the proposed method is demonstrated on a set of 40 flat- and gable-roof buildings using two submeter VHR airborne and two 1-m resolution TerraSAR-X SAR scenes all acquired from the same residential area in Dorsten, Germany. The results show that, in the absence of string disturbing effects, the method is able to estimate the height of flat- and gable-roof buildings in the submeter data to the order of a meter, while the accuracy for the meter resolution spaceborne data is lower but still sufficient to estimate the number of floors of a building. [ABSTRACT FROM AUTHOR]

The waterline method is used to derive the topography of the tidal flats along the German coast by evaluation of synthetic aperture radar (SAR) images. A series of about 70 European Remote Sensing Satellites SAR images of the German Bight taken at different water levels within four years is analyzed to detect the borderline between tidal flats and adjacent water areas using a wavelet-based edge-detection algorithm. After geocoding, the waterlines are combined with the corresponding water levels to represent the topography on an irregularly spaced grid. The water levels are taken from a numerical tide model and corrected with themeasured gauge data. Interpolation of these data into a regular grid yields a topographic map of the intertidal zone. While the general practicability of this method has been demonstrated in previous studies for smaller test areas, this paper is the first attempt to generate maps of a large area on a yearly basis. [ABSTRACT FROM AUTHOR]

TerraSAR-X, the first national German remote-sensing satellite, was launched on-June 15, 2007. It-carries an X-band high-resolution synthetic aperture radar (SAR) instrument featuring imaging modes like StripMap, ScanSAR, and, particularly, SpotLight in a variety of different polarization modes. Primary mission goal is the provision of both science and commercial users with a variety of products from advanced SAR modes. The TerraSAR-X Ground Segment, which is provided by the German Aerospace Center (DLR), constitutes the central element for controlling and operating the TerraSAR-X satellite, for calibrating its SAR instrument, and for archiving the SAR data, as well as generating and distributing the basic data products. This paper depicts the ground-segment layout and describes its major elements. The ordering and product-generation workflow is presented. It introduces the applied prelaunch integration, testing, verification, and validation approach, a major key to the completion not only of the SAR technical-verification program but also the operational qualification of the ground segment itself within the commissioning phase. [ABSTRACT FROM AUTHOR]

TerraSAR-X, the first civil German synthetic aperture radar (SAR) satellite, was successfully launched on June 15, 2007. After 4.5 days, the first processed image was obtained. The overall quality of the image was outstanding; however, suspicious features could be identified which showed precipitation-related signatures. These rain-cell signatures are thoroughly investigated, and the physical background of the related propagation effects is provided. In addition, rain-cell signatures from former missions like SIR-C/X and the Shuttle Radar Topography Mission are provided for comparison. During the commissioning phase of TerraSAR-X, a total of 12000 scenes were investigated for potential propagation effects, and about 100 scenes revealed atmospheric effects to a visible extent. Some of the particularly interesting events were selected and are discussed in greater detail. An interesting case of data acquisition over New York will be presented, which shows typical rain-cell signatures, and the SAR image will be compared with weather-radar data acquired nearly simultaneously (within the same minute). By comparing the images, it can be clearly seen that reflectivities in the weather-radar image of 50 dBZ may cause visible artifacts in SAR images. Furthermore, in this paper, we discuss the influence of the atmosphere (troposphere) on the external calibration of TerraSAR-X. By acquiring simultaneous weather-radar data over the test site and the SAR acquisition, it was possible to flag affected SAR images and to exclude them from the procedure to derive the absolute calibration constant. Thus, it was possible to decrease the 1 σ uncertainty of the absolute calibration factor by 0.15 dB. [ABSTRACT FROM AUTHOR]

The aim of this research work focuses on three basic aspects: at first, the general life and reliability models of electrical equipment are required to evaluate the actual conditions of the electrical equipment; secondly, available maintenance models shall be found to describe actual maintenance actions in continuous processes; thirdly, such a mathematical approach can optimize the maintenance strategies for maximal reliability and minimal costs. This paper demonstrates some actual examples by applying these models and provides the possibility of putting the reliability centered asset management into execution. The systematic quantitative approach can propose different maintenance strategies with the optimum maintenance intervals. [ABSTRACT FROM AUTHOR]

The goal of the International Avogadro Project is the redetermination of Avogadro's constant with an overall uncertainty of 2 × 10-8 at the most. The project partners, therefore, perform measurements of the molar mass and the lattice parameter of a silicon single crystal and of the mass and the volume of a macroscopic high-precision silicon sphere that is made of the same crystal. The results are combined to calculate Avogadro's constant. The determination of the volume of the Avogadro sphere requires unequalled precision in absolute interferometry. For this purpose, a special Fizeau interferometer with spherical reference faces has been developed at the Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany. In particular, systematical influences on an experimental setup can only be detected if relevant influencing parameters are varied. The sphere interferometer of the PTB offers a unique way of investigating the influence of its optical components. The measurement strategy and results are presented in this paper. [ABSTRACT FROM AUTHOR]

The payload ground segment (PGS) for the recently launched German radar satellite, TerraSAR-X, performs the operational data management of the acquired satellite data. This comprises well-known functions such as reception, systematic and ondemand processing, archiving and cataloguing, ordering, and dissemination of digital Earth-observation products. In addition, it comprises new functions like large-scale multimode acquisition ordering by users, integration with a commercial service segment, and new interfaces and workflows within the complete ground segment. The TerraSAR-X PGS is based on the Data Information and Management System (DIMS), the multimission data-handling infrastructure of the German Remote Sensing Data Center (DFD) at the German Aerospace Center. The development and integration of the new functions and complex workflows for TerraSAR-X were achieved and successfully tested on time. After the support of commissioning phase for five months, the system is now operational. As an intended side effect, the PGS for TerraSAR-X is, in several aspects, a pattern being reused for upcoming future missions, thus substantially reducing overall developmental costs. This paper investigates features of the TerraSAR-X PGS that enable the reuse in a multimission environment. It summarizes the achieved enhancements and extensions of DIMS to support the TerraSAR-X mission. Special emphasis is placed on the implementation of the request workflow initiated by user orders and the corresponding data flow within the distributed DFD multimission facility. [ABSTRACT FROM AUTHOR]

The Forschungszentrum Juelich (FZJ) has taken the leadership of a consortium to design and construct the HESR as part of the Facility for Antiproton an Ion Research (FAIR) project at the Gesellschaft fuer Schwerionenforschung (GSI) in Germany. The HESR is a 50 Tm synchrotron/storage ring for antiprotons using superconducting magnet technology, where the development of a bent dipole magnet (cosine theta) with a radius of curvature of 13.9 m and a length of 3.3 m is the major task. On basis of the HERA cooling system the cryogenic design for the HESR has started. One key issue will be the design of several cold-warm, transitions e.g. at PANDA, the E-Cooler and in the region of the stochastic beam cooling system. Another important development is the cryostat layout housing the superconducting curved magnets and in particular the alignment system and measurement equipment for the bent magnets. This paper will present an overview both of the cryogenic layout and the cryostat design. It will give a status report on the achievements so far and discuss the future plans. [ABSTRACT FROM AUTHOR]

This paper presents the results of a measurement campaign conducted in the winter of 2002 around the city of Munich in southern Germany. The primary goal was to evaluate the link performance of the land mobile satellite channel at Ku-band and to characterize the temporal behavior of the channel to help in the evaluation of different fade mitigation techniques for future mobile satellite systems that aim at employing this frequency band. To achieve this objective, first- and second-order channel statistics will be presented, the outage probability of the channel analyzed, and a Markov-chain-based narrowband channel model proposed. [ABSTRACT FROM AUTHOR]

Information about several papers discussed at the 13th International Symposium on Electromagnetic (EM) Launch Technology which was held on May 22-25, 2006 in Berlin, Germany is presented. The event was attended by 169 researchers and engineers from 15 countries. Featured keynote speakers include: Marilyn Freeman from Army's Office of the Secretary; Elizabeth D'Andrea, program manager for the Navy EM Railgun program; and Roger Nadeau from the Army Research, Development and Engineering Command.

Improving the efficacy of emergency responses with digital means is receiving increasing attention. Currently, several innovative information technologies and systems are being developed to raise the situation awareness of first responders like firefighters. Among them, emergency response information systems (ERIS) appear to provide a particularly promising platform, which helps to gather, analyze, and share relevant information during emergencies. However, the conditions under which firefighters accept or reject such systems remain unclear. Existing theories explain the acceptance of information technologies only on a general level that does not consider the specific usage constraints existing in the firefighter domain. To fill this literature gap, we propose a detailed, domain-specific acceptance model with factors that explain the acceptance of ERIS by firefighters. It combines findings of the user satisfaction and the technology acceptance literature and was developed based on the input of 82 domain experts. An evaluation of the acceptance model in a survey with 212 firefighters from Germany indicates that it is effective in predicting a firefighter's intention to use an ERIS. The identified acceptance factors provide guidance for the design and evaluation of ERIS, enabling the so far mostly theoretical benefits of ERIS to be transferred into practical applications more effectively. [ABSTRACT FROM AUTHOR]

A calendar of events is presented for Institute of Electrical & Electronics Engineers(IEEE) Computer Society events around the world in 2007. From April 16-20, 2007, the 23rd IEEE International Conference on Data Engineering will take place in Istanbul, Turkey. From May 6-10, the IEEE VLSI Test Symposium will take place in Berkeley, California. On May 7 until the 9, the 10th IEEE International Symposium on Object, Component, & Service-Oriented Real-Time Distributed Computing will take place in Santorini, Greece. From May 7-11, the 8th International Conference on Mobile Data Management will take place in Mannheim, Germany.

The load-following capabilities of power plants became increasingly important in recent years as a means of ensuring a reliable operation of future power systems. In this work, we propose a generic approach, based on reachability analysis, to rigorously verify the safety of critical components that often pose limitations on the flexibility of conventional power plants to perform fast load changes. The proposed reachability algorithm makes it possible to compute the bounds of all possible trajectories for a range of operating conditions while simultaneously meeting the practical requirements of a real power plant. As an example, we consider the verification of the water level inside a drum unit. In contrast to previous work, our results are based on measurement data of a realistic configuration of a boiler system located within a 450 MW combined cycle plant in Germany. We use an abstract model which considers the modelling errors to ensure that all dynamic behaviors of the process are replicated by the abstraction. Through the implementation of our abstract model, we formally guarantee that the water level inside the drum always remains within safe limits for load changes equivalent to 40 MW which, as a result, exploits the power plant's adaptability and load-following capabilities. [ABSTRACT FROM PUBLISHER]

The intermittent and stochastic nature of solar energy generation systems, climate change, and the inefficiency of modern power systems due to zero inertia have created many challenges for on-grid operators. Solar forecasting systems based on machine learning algorithms are an emerging and effective solution that uses Big Data related to weather phenomena. However, the predictive ability of these algorithms is hampered by the sporadic nature of solar energy generation. In this article, a robust hybrid machine learning system that utilizes multiple linear regression (MLR) and a Pearson correlation coefficient (PCC) was tested on solar power plant sites of varying capacities in Germany (100–8500 kW). The volume of Big Data features can be reduced by focusing on the features that significantly improve the reliability of the mid-term forecasting system. In this way, drastic fluctuations in the prediction of photovoltaic (PV) power generation can be avoided. The results of our approach are evaluated regarding real-world data using the extreme gradient boosting (XGBoost) with feature engineering, and principal component analysis (PCA), in order to forecast PV energy, rank, and track the importance of feature engineering for different PV capacities. Furthermore, we found that the need for selectivity and reduction of performance error was supported by ridge regression. In addition, the proposed novel XGBoost forecast system decreased the root-mean-square error (RMSE) and mean absolute error (MAE) by 30% and 18%, respectively, compared to the Autoencoder and long short-term memory (LSTM) for same datasets. Furthermore, the CoD determination coefficient ($R^{2}$) increased by 85% compared to the statistical model's autoregressive integrated moving average (ARIMA). [ABSTRACT FROM AUTHOR]

The article introduces the December 12, 1998 issue of the journal, IEEE Transactions on Software Engineering. In the context of software and systems engineering, work in scenario management has so far been fragmented. Therefore a call for papers for a special issue of this journal on scenario management was published. The goal was to produce a collection of some of the major research efforts on scenario management, taking a broad view of what is or should be relevant to software and systems engineering. In order to draw scenario research and practice from different reference disciplines closer together, the CREWS ESPRIT Long Term Research Project of the European Communities organized an interdisciplinary workshop on scenario management, held in Germany. The first three issue of the journal describe some of the components of a scenario-based approach developed in the CREWS project. The following three papers investigate scenarios themselves as formal objects, from which more abstract knowledge is derived by formal reasoning techniques.

In this study, we analyze a lightning event, which occurred on March 20, 2020 at 8:05 pm. Three other-triggered upward lightning developed simultaneously from the 150 m high Peissenberg Tower and from two small structures, a 35 m high mast and a 25 m high Church Tower. The velocity of the upward leaders ranged from 2.1 × 104 to 4.1 × 104 m/s. In addition, to these upward leaders, the total of 51 isolated leaders were observed. These leaders had no contact to the lightning channel or to other leaders or to objects at ground, i.e., most of them did not develop along a path of the decayed channel of a previous leader. Therefore, it is doubtful whether the isolated leaders may be recoil leaders. The lightning to the Peissenberg Tower was a bipolar flash with a current, which contained several (unusual) positive and negative components. The first component was a negative initial continuous current (ICC), followed by a strong negative current component, with a maximum of 4.1 kA and a duration of 40.2 ms. This current component was superimposed by a pulse train of 26 extremely strong current pulses with peak values up to 1.87 kA. The negative current component was followed by a positive current pulse with a peak value of 31 kA, a 10%–90% risetime of 1.80 ms, an action integral of 0.68 MJ/Ω, a full width on half maximum of 0.67 ms and a duration of 15.7 ms. The positive current pulse was superimposed by strong oscillations with the frequency of about 5 kHz and with amplitudes up to 10.2 kA. After its cessation, the positive current pulse turned into a negative continuing current with the duration of 217 ms, the maximum of 245 A, and the transferred charge of 18.0 C. The negative continuing current was followed by a negative return stroke which in turn was followed by a positive continuing current, which lasted 19.7 ms and had a maximum of 173 A. Finally, a second negative return stroke occurred, which was followed by a short negative continuing current with an M-component. [ABSTRACT FROM AUTHOR]

An increasing number of municipalities are striving for energy autonomy. This study determines in which municipalities and at what additional cost energy autonomy is feasible for a case study of Germany. An existing municipal energy system optimization model is extended to include the industrial, commercial and personal transport sectors. Multiple regression methods are benchmarked in order to identify the model best suited for the transfer of individual optimization results to a large proportion of German municipalities. The resulting levelized cost of energy (LCOE) from the optimization of representative case study municipalities are transferred using energy-relevant indicators. The study demonstrates that energy autonomy is technically feasible in 6,314 (56%) municipalities. Thereby, the LCOEs increase in the autonomous case on average by 0.41 €/kWh compared to the minimum cost scenario. Apart from energy demand, base-load-capable bioenergy and deep geothermal energy have the greatest influence on the LCOEs. Overall, it appears that municipal energy autonomy is not economically viable under current framework conditions. This study represents a starting point for defining possible scenarios in studies of future national energy system or transmission grid expansion planning, which for the first time consider completely energy autonomous municipalities. [ABSTRACT FROM AUTHOR]

Pursuing long-term climate stabilisation scenarios subjects power, heat, industry, and transport sectors to undergo fundamental transitions towards fully renewable energy systems. Cost-efficient strategies involve the integration of energy vectors, introducing additional cross-sectoral electricity demand and flexibility for traditional power sectors. When performing cross-sectoral capacity expansion planning (CEP) analyses of low-carbon energy systems for decision making support, the underlying mathematical optimisation problems easily become intractable. To overcome the computational challenges of optimising real-world instances of future energy systems with adequate representations of temporal, spatial, and technological detail, this work investigates different modelling approaches for flexible heat pump systems at the power and heat sector interface of the long-term energy system model SCOPE SD. A comparative case study carried out for a net-neutral decarbonisation scenario in Europe and Germany highlights the implications of using model aggregation techniques. It is shown that the proposed modelling approaches can present computational benefits at only limited cost of result accuracy. However, poorly implemented grouping strategies can lead to high result inaccuracies and even a lack of performance improvements. [ABSTRACT FROM AUTHOR]

A calendar of computer-related events for January to November 2010 is presented which includes the IEEE International Workshop on Wireless, Mobile and Ubiquitous Technology in Education in Kaohsiung, Taiwan, the PerCom 2010 International Conference on Pervasive Computing and Communications in Mannheim, Germany and International Conference on Data Engineering in Long Beach, California.

Finding new industry partners poses a challenge to many public research organizations. This article explores how statistical classification can support partner selection at the example of the Fraunhofer Society in Germany, Europe's largest public organization for applied research. We use internal cooperation data and feature sets based on unstructured data, i.e., text and industry codes, both of which describe business activities of firms. An important advantage of this data is that it is available for most companies in Germany, even small and medium enterprises, which allows for an almost complete screening of the market, in contrast to using other data sources, e.g., patents. In addition, we also include economic variables linked to firms, as turnover, number of employees/managers and firm age. We report the performance of various classification techniques such as logistic regression, support vector machines, and random forests in our dataset for diverse combinations of feature sets. Results show that simple methods with fewer parameters remain competitive in comparison to complex ones. Overall, the performance of most classifiers is high enough to support the decision process of finding new industry partners for public research. [ABSTRACT FROM AUTHOR]