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991.
Steady state experiments like Wendelstein 7-X have to deal with large amounts of data of different kind. Discharge lengths may last from less than a second up to 30 min. During this time diagnostics will measure data in different discharge phases with different rates depending on the physical program. Furthermore the technical configuration of all devices must be logged during the discharge as well as between experiment phases. This is necessary to allow supervision of constantly running devices. All measured data must be stored together in a common database to make it easily accessible and reduce the effort to combine data. Because of these requirements a continuous data acquisition system must be provided where data may exist at any time. Intelligent methods for browsing and retrieval of the acquired data from the common database are desired. This includes calendar-based time interval selection, overview plots for intervals that cover several days and online views of the last stored data. The contribution will explain the challenges and the advantages induced by this kind of data access methods. Existing and planned solutions for Wendelstein 7-X will be depicted. Particularly the “Data Browser” – a graphical tool specially designed to fulfil these tasks at W7-X – will be presented.  相似文献   
992.
The development of the IFMIF (International Fusion Material Irradiation Facility) High Flux Test Module in the EVEDA (Engineering Validation and Engineering Design Activities) phase up to 2013 includes conceptual design, engineering analyses, as well as design and engineering validation by building of prototypes and their testing. The High Flux Test Module is the device to facilitate the irradiation of SSTT samples of RAFM steels at temperatures 250–550 °C and up to an accumulated irradiation damage of 150 dpa. The requirements, the current design and the performance of the module are discussed, and the development process is outlined.  相似文献   
993.
Process management and workflow optimisation have become key issues of good laboratory management and now seem to be predominant over traditional challenges such as the quality of analytical testing. The first author of this paper has conducted several workflow optimisation studies for clinical laboratories in Europe (Universities of Zurich and Amsterdam, Manchester Royal Infirmary and others) and in the US (University of Virginia), using a laboratory-specific simulation software called Simlab™ for realistic computer modeling of laboratory scenarios. Since data input and calibration of the models against reality have always been a challenge in these studies, we looked into possibilities of using automated data extraction to extract as much information as possible from the laboratory information system. In this paper we describe our first experience with a Microsoft Excel™-based software program called Simlab 1, which uses the ASCII file transfer protocol to extract data from the LIS.  相似文献   
994.
We have studied MOVPE-grown interior GaAs/AlAs interfaces using highly selective etching combined with atomic force microscopy. We observe substantial restructuring for samples grown on both (100) exact and vicinal substrates. Interface structures differ significantly from sample surfaces after cool-down. On (100) exact substrates, the macroscopic monolayer island and terrace structure smoothes during growth interruptions over the whole 2 min period of time studied. A new, mesoscopic scale of roughness is detected for the first time. This structure does not depend on growth interruption time but does change its typical size at different growth temperatures. On vicinal substrates, we observe and quantify step bunching during growth interruption. The growing surface itself is smooth, in sharp contrast to the corresponding macrostepped GaAs sample surface obtained after cooling down.  相似文献   
995.
Parametrizing compactly supported orthonormal wavelets by discrete moments   总被引:1,自引:0,他引:1  
We discuss parametrizations of filter coefficients of scaling functions and compactly supported orthonormal wavelets with several vanishing moments. We introduce the first discrete moments of the filter coefficients as parameters. The discrete moments can be expressed in terms of the continuous moments of the related scaling function. To solve the resulting polynomial equations we use symbolic computation and in particular Gröbner bases. The cases of four to ten filter coefficients are discussed and explicit parametrizations are given.  相似文献   
996.
Zusammenfassung Der Palestrina-Kontrapunkt nimmt in der Musiktheorie-Ausbildung eine wichtige Stellung ein.  相似文献   
997.
998.
A trilateral intercomparison of photometric units between NIST (USA), NPL (UK), and PTB (Germany) has been conducted to update the knowledge of the relationship between the photometric units disseminated in the three countries. The luminous intensity unit (cd), the luminous responsivity scale (A/lx), and the luminous flux unit (lm) maintained at each laboratory were compared by circulating transfer standard lamps and photometers. The results showed that the relative luminous intensity values, with respect to the average, measured by NIST, NPL, and PTB were 1.0014, 1.0021, and 0.9966; the relative inverse values of the luminous responsivity (corresponding to illuminance) were 1.0023, 1.0011, and 0.9965; the relative luminous flux values were 0.9994, 1.0034, and 0.9972, respectively. The results agreed within the stated uncertainties of the units maintained at the three laboratories.  相似文献   
999.
An enantioselective synthesis of tert-butyl (5S,6R)-(E)-5-tert-butyldimethylsilyloxy-6-methyl-2,7-octadieno ate, a precursor for the synthesis of the antimitotic macrolides cryptophycin A and arenastatin A (cryptophycin-24), is presented. The key step in the reaction sequence features a crotyl boration that sets both stereocenters that become the C16 hydroxyl and Cl' methyl in the cryptophycins. Homologation of the terminal olefin via a Heck reaction is presented.  相似文献   
1000.
MHD effects arising in plasma sources, such as short-pulsed magnetoplasmadynamic generators and inductively heated plasma generators, are analyzed with both algebraic models and measured data. Functional principles of the sources based on their MHD behavior are explained. Moreover, Stewart numbers in the order of magnitude of at least 10−1 are calculated for the systems and qualified as an identifier for the magnetic influence on plasmas. Here, the considered plasma systems that are a priori known as MHD systems were used to determine typical values of the Stewart number. Based on this experience the concept of a plasma probe to magnetically influence or control weakly ionized free stream plasma flows is presented.  相似文献   
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