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1.
Andrea Romei Matteo Sciolla Franco Turini Marlis Valentini 《Concurrency and Computation》2007,19(13):1785-1809
KDDML‐G is a middleware language and system for knowledge discovery on the grid. The challenge that motivated the development of a grid‐enabled version of the ‘standalone’ KDDML (Knowledge Discovery in Databases Markup Language) environment was on one side to exploit the parallelism offered by the grid environment, and on the other side to overcome the problem of data immovability, a quite frequent restriction on real‐world data collections that has principally a privacy‐preserving purpose. The last question is addressed by moving the code and ‘mining’ the data ‘on the place’, that is by adapting the computation to the availability and localization of the data. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
2.
Marlis Wilplinger Isolde Schönsleben und Werner Pfannhauser 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(6):521-523
The chromium content in foods is relatively low and the most foods have a content below 0,1 ppm. Only spices, cacao, cacao products, poppy and whole meal products contain higher contents. The often published high chromium content of corn germ oil could not be verified. We did not find any chromium enrichment in the entrails of a cow. In addition the chromium contents of each food are strong deviated. The analysed values were sometimes lower than in literature. We expect that the elder values are higher because of different contaminations in some cases. 相似文献
3.
J. Brillo H. Behnken A. Drevermann Y. Plevachuk E. Pagounis V. Sklyarchuk L. Sturz 《International Journal of Heat and Mass Transfer》2011,54(19-20):4167-4174
Ni–Mn–Ga magnetic shape memory alloys (MSMA) are well-known smart materials for actuation applications, due to their large magnetic field-induced shape change of up to 10%. The production of larger amounts of single-crystalline material from these alloys with reproducible and homogeneous properties is demanding and calls for optimization of the corresponding crystal growth process. In order to support this optimization, sensitive process parameters are varied in simulations and their effects are studied.Here, we report on thermal field simulations in a Bridgman–Stockbarger furnace. The lab furnace is equipped with liquid metal cooling (LMC) to achieve high and homogeneous thermal gradients at the crystallization front during crystal growth of cylindrical Ni–Mn–Ga-rods. The calibration of the thermal simulation model requires (i) the knowledge/measurement of the relevant thermophysical properties of the Ni–Mn–Ga alloy as functions of temperature and (ii) thermal data from a reference benchmark experiment in the lab furnace using the same alloy.The calibrated simulation model is used for the simulation of a specific virtual Bridgman-experiment and for the determination of the temperature distributions. Moreover, the influence of the type of liquid metal coolant on the simulation results is investigated. 相似文献
4.
Feller C Günther R Hofmann HJ Grunow M 《Chembiochem : a European journal of chemical biology》2006,7(9):1410-1418
D-3-Hydroxybutyrate dehydrogenase from Pseudomonas putida (EC 1.1.1.30) belongs to the family of short-chain dehydrogenases/reductases (SDRs). It catalyzes the reversible and stereospecific oxidation of D-3-hydroxybutyrate (D-3-HB) to acetoacetate with the aid of NAD(+) as coenzyme. This study contributes to understanding the mechanism and the high specificity of this enzyme towards its negatively charged and hydrophilic substrate. Sequence comparison of 44 bacterial HBDHs shows the residues Gln91, His141, Lys149, Lys192, and Gln193 to be strictly conserved. Site-directed mutagenesis of these amino acids to alanine and subsequent kinetic characterization of the mutated enzymes provides insight into the importance of these residues for substrate recognition and catalysis. Docking studies and molecular-dynamics simulations based on a three-dimensional structure model of a complex between P. putida HBDH and its coenzyme obtained by comparative molecular modeling were performed and provided deeper insight into the binding of the ligands at the molecular level. They show the residues Gln91, His141, Gln193, and, in particular, Lys149 to be involved in a hydrogen-bonding network with the carboxylate group of the substrate. 相似文献
5.
A. Drevermann U. Hecht V. Witusiewicz B. Böttger S. Rex 《Microgravity science and technology》2005,16(1-4):45-49
Within the frame of the joint ESA research program “SETA” (Solidification along a Eutectic path in Ternary Alloys) univariant solidification is investigated in preparation of experiments onboard the ISS. The ternary eutectic alloys under examination belong to the ternary system Al-Cu-Ag. The focus is on coupled eutectic growth of two solid phases along the univariant eutectic groove (marked (1) in fig. 1 and 2) that extends from the binary Al-Cu eutectic towards the ternary nonvariant eutectic with increasing Ag content. This presentation reports on three different approaches to the topic: by means of thermodynamics, experiments and microstructure simulations and their interaction. Experiments and simulations are compared regarding planar and cellular microstructure formation and phase compositions. Thermodynamic data and calculations serve as interpretational link between experiment and simulation and as main input to the simulations. 相似文献
6.
KK Chan JL Cohen JF Gross KJ Himmelstein JR Bateman Y Tsu-Lee AS Marlis 《Canadian Metallurgical Quarterly》1978,62(8):1161-1171
A ten-compartment flow-limited pharmacokinetic model scaled from rabbit tissue distribution data was used to predict plasma adriamycin concentrations in 23 patients and adriamycin tissue uptake in nine surgery patients following iv bolus doses of 10--60 mg/m2. The predicted concentrations were compared to experimentally determined adriamycin using a specific thin-layer chromatographic fluorescence scanning procedure. The predicted plasma time course for 11 of 16 patients with relatively normal liver and kidney function agreed closely with the observed plasma time course. Deviations in the other five patients were ascribed to possible changes in the profile of metabolite formation and/or fluctuations in biliary clearance. All four patients with elevated serum bilirubin demonstrated significantly higher and more prolonged plasma levels than predicted. The results of two patients with impaired kidney function and one patient with both hepatic and renal involvement were inconclusive. The comparison between predicted and observed tissue concentrations in biopsy samples was varied; however, all were within an order of magnitude. It is concluded that the model depicts adriamycin uptake and distribution reasonably well; however, more needs to be known concerning individual variation in metabolic and biliary excretion rates for this to become more patient-specific. Also, a tumor compartment appears to be an important addition in modifying the model to allow for clinical utility. 相似文献
7.
In thermoelectric applications, optimized thermal contacts are essential to enable efficient and homogeneous flow of heat currents. Thermomechanical stresses may lead to surface deformation, which alters the thermal contact. As a result, the heat current density is reduced and no longer homogeneous. Also an undesired temperature gradient perpendicular to the heat flow develops, and hence this temperature gradient again causes thermomechanical stresses. The described thermomechanical problems are particularly important in applications where high operating temperatures and hence large temperature differences are used. Also, system durability is a crucial aspect, especially in applications where thermal cycles occur (i.e., in the field of waste heat regeneration of car combustion engines). We describe a measuring technique to detect and evaluate the influence of these deformations. To analyze the surface and external points of contact of a thermoelectric generator (TEG), a measurement setup based on speckle interferometry is used. Temperature gradients as well as small surface deflections in the μm range have to be measured simultaneously. Therefore, an optical as well as a thermography camera are used to create a holistic image of the deformation and to analyze the influence of this deformation on the TEG structure. 相似文献
8.
H. Drevermann W. Krischer 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,239(2):160-174
The human perception of high-energy pictures may be considerably facilitated if one enhances the interesting features of the image by modifying its geometry. Several examples for such an improvement are shown for pictures from bubble chambers, for a drawing of a fixed target experiment and for a simulated image from a collider experiment. 相似文献
9.
Within the last 10 years, the cryopump was added to the range of the pumps used in the high vacuum and ultra high vacuum fields. The choice of the right pump often turns out to be difficult. One of the reasons could surely be that the user is not often familiar with the properties of the cryopumps. The article is meant to make the reader aware of all possible criteria, which in turn will make it easier for him to make a decision concerning the pump required for the application. The refigerator cryopumps can be used in any application for which hydrocarbonfree vacuum is required as well as a high pumping speed for almost all gases. 相似文献
10.
In this paper we propose a numerical method for approximating the product of a matrix function with multiple vectors by Krylov subspace methods combined with a QR decomposition of these vectors. This problem arises in the implementation of exponential integrators for semilinear parabolic problems. We will derive reliable stopping criteria and we suggest variants using up- and downdating techniques. Moreover, we show how Ritz vectors can be included in order to speed up the computation even further. By a number of numerical examples, we will illustrate that the proposed method will reduce the total number of Krylov steps significantly compared to a standard implementation if the vectors correspond to the evaluation of a smooth function at certain quadrature points. 相似文献