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The European Gyrotron Consortium (EGYC) is developing the European 1 MW, 170 GHz Continuous Wave (CW) industrial prototype gyrotron for ITER in cooperation with Thales Electron Devices (TED) and Fusion for Energy (F4E). This conventional, hollow-cavity gyrotron, is based on the 1 MW, 170 GHz Short-Pulse (SP) modular gyrotron that has been designed and manufactured by the Karlsruhe Institute of Technology (KIT) in collaboration with TED. Both gyrotrons have been tested successfully in multiple experiments. In this work we briefly report on the results with the CW gyrotron at KIT and we focus at the experiments at the Swiss Plasma Center (SPC). In addition, we present preliminary results from various upgrades of the SP tube that are currently tested at KIT.
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28 | 0:00:00 Start 0:00:05 Einleitung 0:00:28 Dominik Schreiber - SAT Solving and Automated Planning 0:00:41 Overview 0:01:51 The SAT Problem 0:03:39 SAT Solving 0:05:06 Parallel SAT Solving 0:09:30 Automated Planning 0:13:20 SAT-based Planning 0:17:44 Outlook: Future Research and Teaching 0:23:16 Sebastian Lamm - Distributed Connected Components 0:23:45 Connected Components and Applications 0:25:23 Sequential Algorithms 0:26:16 General Framework 0:29:04 All-Reduce (AR) - Algorithm 0:31:14 Union-find merging (UFM) 0:35:26 Graph Contraction (GC) - Algorithm 0:38:21 Label Propagation (LP) 0:40:44 Comparison 0:43:14 Conclusion 0:44:40 Sebastion Schlag - High Quality Hypergraph Partitioning 0:47:24 Applications 0:48:57 Parallel Sparse-Matrix Vector Product (SpM x V) 0:52:09 From SpM x V to Hypergraph Partitioning 0:56:33 How does Hypergraph Partitioning work? 0:59:27 Taxonomy of Hypergraph Partitioning Tools 1:01:07 Why Yet Another Multilevel Algorithm? 1:05:30 Latest Experimental Results 1:08:45 KaHyPar - Karlsruhe Hypergraph Partitioning 1:10:20 Tobias Maier - Parallele Algorithmen - Einschub Shared Memory Datenstrukturen 1:12:12 Concurrent Hash Table 1:17:19 Migration als Lösung 1:20:33 Vergrößern der Hash Tabelle 1:24:09 Deallocation Problem
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Sodium-ion batteries (SIBs) are a recent development being promoted repeatedly as an economically promising alternative to lithium-ion batteries (LIBs). However, only one detailed study about material costs has yet been published for this battery type. This paper presents the first detailed economic assessment of 18,650-type SIB cells with a layered oxide cathode and a hard carbon anode, based on existing datasheets for pre-commercial battery cells. The results are compared with those of competing LIB cells, that is, with lithium-nickel-manganese-cobalt-oxide cathodes (NMC) and with lithium-iron-phosphate cathodes (LFP). A sensitivity analysis further evaluates the influence of varying raw material prices on the results. For the SIB, a cell price of 223 €/kWh is obtained, compared to 229 €/kWh for the LFP and 168 €/kWh for the NMC batteries. The main contributor to the price of the SIB cells are the material costs, above all the cathode and anode active materials. For this reason, the amount of cathode active material (e.g., coating thickness) in addition to potential fluctuations in the raw material prices have a considerable effect on the price per kWh of storage capacity. Regarding the anode, the precursor material costs have a significant influence on the hard carbon cost, and thus on the final price of the SIB cell. Organic wastes and fossil coke precursor materials have the potential of yielding hard carbon at very competitive costs. In addition, cost reductions in comparison with LIBs are achieved for the current collectors, since SIBs also allow the use of aluminum instead of copper on the anode side. For the electrolyte, the substitution of lithium with sodium leads to only a marginal cost decrease from 16.1 to 15.8 €/L, hardly noticeable in the final cell price. On the other hand, the achievable energy density is fundamental. While it seems difficult to achieve the same price per kWh as high energy density NMC LIBs, the SIB could be a promising substitute for LFP cells in stationary applications, if it also becomes competitive with LFP cells in terms of safety and cycle life.
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Improving the understanding and representation of heavy precipitation is crucial to prevent its hazards. A powerful means to reduce errors is to assimilate high-resolution humidity GPS observations. Here, novel experiments employing sub-hourly atmospheric GPS, in-situ observations and nudging are used to study the impact of moisture corrections on convection. This work adds new explanations on the sensitivity of extreme precipitation to moisture changes and on the added value of nudging GPS.
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Der Eindeutigkeitssatz für Maße besitzt vielfältige Anwendungen in der Maßtheorie und in der Stochastik. In diesem Video wird der Satz vorgestellt und bewiesen. Schlagkräftiges Hilfsmittel ist das Konzept des Dynkin-Systems.
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The first divertor was installed in the JET machine between 1992 and 1994 and was operated with carbon tiles and then beryllium tiles in 1994–5. Post-mortem studies after these first experiments demonstrated that most of the impurities deposited in the divertor originate in the main chamber, and that asymmetric deposition patterns generally favouring the inner divertor region result from drift in the scrape-off layer. A new monolithic divertor structure was installed in 1996 which produced heavy deposition at shadowed areas in the inner divertor corner, which is where the majority of the tritium was trapped by co-deposition during the deuterium-tritium experiment in 1997. Different divertor geometries have been tested since such as the Gas-Box and High-Delta divertors; a principle objective has been to predict plasma behaviour, transport and tritium retention in ITER. Transport modelling experiments were carried out at the end of four campaigns by puffing 13C-labelled methane, and a range of diagnostics such as quartz-microbalance and rotating collectors have been installed to add time resolution to the post-mortem analyses. The study of material migration after D-D and D-T campaigns clearly revealed important consequences of fuel retention in the presence of carbon walls. They gave a strong impulse to make a fundamental change of wall materials. In 2010 the carbon divertor and wall tiles were removed and replaced with tiles with Be or W surfaces for the ITER-Like Wall Project.
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Tropospheric ozone (O3) is one of the most prominent air pollution problems in Europe and other countries worldwide. Human health is affected by O3 via the respiratory as well the cardiovascular systems. Even though trees are present in relatively low numbers in urban areas, they can be a dominant factor in the regulation of urban O3 concentrations. Trees affect the O3 concentration via emission of biogenic volatile organic compounds (BVOC), which can act as a precursor of O3, and by O3 deposition on leaves. The role of urban trees with regard to O3 will gain further importance as NOx concentrations continue declining and climate warming is progressing—rendering especially the urban ozone chemistry more sensitive to BVOC emissions. However, the role of urban vegetation on the local regulation of tropospheric O3 concentrations is complex and largely influenced by species-specific emission rates of BVOCs and O3 deposition rates, both highly modified by tree physiological status. In this review, we shed light on processes related to trees that affect tropospheric ozone concentrations in metropolitan areas from rural settings to urban centers, and discuss their importance under present and future conditions. After a brief overview on the mechanisms regulating O3 concentrations in urban settings, we focus on effects of tree identity and tree physiological status, as affected by multiple stressors, influencing both BVOC emission and O3 deposition rates. In addition, we highlight differences along the rural-urban gradient affecting tropospheric O3 concentrations and current knowledge gaps with the potential to improve future models on tropospheric O3 formation in metropolitan areas.
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