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101.
102.
Zusammenfassung Ziel dieses Artikels ist es, einen überblick über technische Sicherheitsl?sungen für Intranets zu geben. Ein Modell, das
die Anforderungen an ein Sicherheitssystem in Form von abstrakten Diensten abbildet, dient dazu, verschiedene L?sungsalternativen
zur Realisierung der unterschiedlichen Dienste auf Basis offener Standards oder generalisierter Produktklassen beurteilen
zu k?nnen. Darauf aufbauend wird eine beispielhafte Referenzarchitektur für Unternehmen auf Basis einer X.509 Public-Key-Infrastruktur
entworfen.
相似文献
103.
Supported gold catalysts, e.g., Au on Al2O3, Fe2O3, CeO2, MnO2, TiO2, ZrO2, activated carbon, titanium silicalite TS‐1, were prepared and used for the isomerization of linoleic acid (cis‐9,cis‐12‐octadecadienoic acid) to conjugated linoleic acids (CLA) in the presence of hydrogen at 165 °C in a batch reactor. The best results were obtained using a catalyst with 2 wt % Au on TS‐1, which exhibits a high selectivity (78 %) towards CLA. The two biologically active target CLA isomers, i.e., cis‐9,trans‐11‐CLA and trans‐10,cis‐12‐CLA, were the main products. During the isomerization of linoleic acid to CLA, consecutive reactions also took place. These were the hydrogenation of linoleic acid and CLA to monounsaturated octadecenoic acids and the further hydrogenation of monounsaturated acids to stearic acid. Thus, gold catalysts are capable of isomerizing linoleic acid to CLA and hydrogenating their double bonds to an extent that depends on the Au catalyst used. 相似文献
104.
Detlef Stiller Birgit Gaschler-Markefski Frank Baumgart Frank Schindler Claus Tempelmann Hans-Jochen Heinze henning Scheich 《Magma (New York, N.Y.)》1997,5(4):275-284
Prosodic modulation of speech provides information about emotional states of speakers (affective prosodies) or serves as syntactic
markers to change linguistic aspects of speech (linguistic prosodies). Previous electrophysiological investigations and studies
on patients with right or left hemisphere damage showed nonuniform results with respect to lateralization of prosodic processing.
In this study 20 healthy right-handed volunteers were investigated with functional magnetic resonance imaging of the acoustically
responsive areas on the supratemporal plane while detecting phonemes as control targets or prosodies in strings of nonsense
syllables and adjectives, the latter randomly intonated in a declarative, interrogative, commanding, happy, or sad fashion.
In control task A the phoneme /a/ was detected in the syllables. In control task B the phoneme /a/ was detected in the adjectives,
and in the experimental task C the sad intonations (affective) and in the experimental task D the interrogative intonations
(linguistic) had to be detected in the same material. In task A intensity-weighted volumes of activated voxels were not different
in the two hemispheres (laterality index 0). In task B with an irrelevant phoneme detection with respect to prosodic material,
the population split into two subgroups with similar right or left hemispheric lateralization of activity leading to an absolute
laterality index of 26.8 across all subjects. During detection of affective prosodies (task C), lateralization was maintained
yet the absolute laterality index reduced to 14.5, while there was no lateralization during detection of linguistic prosodies.
The sum of activations in the two hemispheres was the same across all tasks and subgroups, which suggests that the lateralizations
occurring with presentation and detection of prosodic material depend on a redistribution of activity between hemispheres. 相似文献
105.
Volker Claus 《Informatik-Spektrum》2005,28(2):124-128
Ein Ranking beruht meist auf einer Abbildung einer endlichen Menge von (hochkomplexen) Strukturen auf die reelle Achse. 相似文献
106.
107.
Simplified counter-current distribution procedures are described which allow correct analysis of the α acids and iso α acids content of hop extracts. 相似文献
108.
Masoud Kayhanian Amardeep Singh Claus Suverkropp Steve Borroum 《Canadian Metallurgical Quarterly》2003,129(11):975-990
The objective of this study was to evaluate correlations between annual average daily traffic (AADT) and storm water runoff pollutant concentrations generated from California Department of Transportation (Caltrans) highway sites. Analyses of data collected from the Caltrans four-year (1997–2001) highway runoff characterization program revealed that, in general, pollutant concentrations from urban highways were higher than those found from nonurban highways. For a limited number of pollutants, however, the concentrations from nonurban highways were found to be higher than the concentrations from urban highways. No direct linear correlation was found between highway runoff pollutant event mean concentrations and AADT. However, through multiple regression analyses, it was shown that AADT has an influence on most highway runoff constituent concentrations, in conjunction with factors associated with watershed characteristics and pollutant build-up and wash off. The other noticeable factors shown to influence the accumulation of pollutants on highways were antecedent dry period, drainage area, maximum rain intensity, and land use. 相似文献
109.
Claus B. Madsen 《Machine Vision and Applications》1997,9(5-6):291-303
The paper presents an analysis of the stability of pose estimation. Stability is defined as sensitivity of the pose parameters
towards noise in image features used for estimating pose. The specific emphasis of the analysis is on determining {how the
stability varies with viewpoint} relative to an object and to understand the relationships between object geometry, viewpoint,
and pose stability. Two pose estimation techniques are investigated. One uses a numerical scheme for finding pose parameters;
the other is based on closed form solutions. Both are “pose from trihedral vertices” techniques, which provide the rotation
part of object pose based on orientations of three edge segments. The analysis is based on generalized sensitivity analysis
propagating the uncertainty in edge segment orientations to the resulting effect on the pose parameters. It is shown that
there is a precomputable, generic relationship between viewpoint and pose stability, and that there is a drastic difference
in stability over the range of viewpoints. This viewpoint variation is shared by the two investigated techniques. Additionally,
the paper offers an explicit way to determine the most robust viewpoints directly for any given vertex model. Experiments
on real images show that the results of the work can be used to compute the variance in pose parameters for any given pose.
For the predicted {instable} viewpoints the variance in pose parameters is on the order of 20 (degrees squared), whereas the
variance for robust viewpoints is on the order of 0.05 (degrees squared), i.e., two orders of magnitude difference. 相似文献
110.
A section is born: Studies in Automated Reasoning 相似文献