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排序方式: 共有3537条查询结果,搜索用时 281 毫秒
991.
992.
Zusammenfassung Mit der Einführung des elektronischen Personalausweises steht in Deutschland eine eID-L?sung mit potentiell sehr weiter Verbreitung
vor der Tür. Der Beitrag diskutiert, wie solche L?sungen im Identit?tsmanagement eingesetzt und wie sie in Zukunft verbessert
werden k?nnen.
Dr. Christoph Sorge Research Scientist, NEC Laboratories Europe, Heidelberg. T?tigkeitsschwerpunkt: Forschung im Bereich der Netzsicherheit,
u.a. Identit?tsmanagement
Dr. Dirk Westhoff Chief Researcher, NEC Laboratories Europe, Heidelberg. T?tigkeitsschwerpunkt: Forschung in den Bereichen mobile drahtlose
Sicherheit, Identit?tsmanagement 相似文献
993.
994.
The European Water Framework Directive recommends investigating trends in groundwater head time series by means of trend analysis in order to assess possible harmful anthropogenic impacts. This approach encounters substantial problems. Usually the Mann-Kendall test is applied which does not consider interactions between trends and auto-correlation in the data. These are very common in groundwater head time series. As a consequence, trend significance has been substantially overestimated. In addition, significance, magnitude and trend sign depend strongly on the selected time span. A functional analysis based on a principal component analysis of groundwater head time series was introduced as an alternative. It yielded very robust results, independent from the selected periods. To determine anthropogenic impacts on groundwater heads, deviations of observed data from the expected behaviour could be investigated. Data requirements and the computational effort of this approach are about the same compared to trend analysis. 相似文献
995.
Christoph F-J Goetz 《Datenschutz und Datensicherheit - DuD》2010,34(12):811-814
Es gibt einen breiten Konsens, dass auch in der Gesundheitsversorgung Papier gebundene Kommunikation durch elektronische Medien
ersetzt werden muss. Erwartungen und Nutzen für die verfassten Organisationen sind bereits gefestigt. Wie wird der Bürger
in diese Entwicklung eingebunden? 相似文献
996.
This article focuses on the distribution of costs induced by the integration of electricity generation from renewable energy sources (RES-E). The treatment to distribute these costs on different market actors is crucial for its development. For this purpose, individual actors of electricity markets and several cost categories are identified. According to the defined cost structure, possible treatments to distribute the individual cost categories on different relevant actors are described. Finally, an evaluation of the cost distribution treatments based on an economic analysis is given. Economic efficiency recommends that clearly attributable (shallow) grid connection as well as (deep) grid costs are charged to the corresponding RES-E producer and that the RES-E producers are also charged the regulating power costs. However, deep grid integration costs should be updated to reflect evolving scarcities. Also regulating power costs should reflect actual scarcity and thus be symmetric and based on real-time prices, taking into account the overall system imbalance. Moreover, the time span between the closure of the spot market and actual delivery should be chosen as short as possible to enable accurate RES-E production forecasts. 相似文献
997.
Biometric data have been integrated in all new European passports, since the Member States of the European Union started to implement the EU Council Regulation No 2252/2004 on standards for security features and biometrics in passports. The additional integration of three-dimensional models promises significant performance enhancements for border controls. By combining the geometry-and texture-channel information of the face, 3-D face recognition systems provide an improved robustness while processing variations in poses and problematic lighting conditions when taking the photo. 相似文献
998.
Renaud Metz Jonathan Morel Mourad Houabes Julien Pansiot Merdad Hassanzadeh 《Journal of Materials Science》2007,42(24):10284-10287
High current characterization of SnO2-based varistors have been carried out and the results obtained have been compared with those ZnO-based commercial surge arresters.
It is shown that for a high temperature sintering (1350 °C), the leakage current, breakdown voltage and the saturation at
high current density are similar between both types of surge arresters. The paper shows, for the first time, that the high
breakdown voltage observed with tin dioxide cannot be easily maintained since the saturation of the ceramics is reached for
current densities of several amperes per square centimetre. 相似文献
999.
Yasushi Umeda Shozo Takata Fumihiko Kimura Tetsuo Tomiyama John W. Sutherland Sami Kara Christoph Herrmann Joost R. Duflou 《CIRP Annals》2012,61(2):681-702
Life cycle engineering (LCE) is a key concept for promoting environmentally sustainable practices among manufacturing firms. A major hurdle in the implementation of LCE is the lack of a systematic and strategic method to design or plan an entire product life cycle. To address this issue, this keynote provides a framework for life cycle development and proposes the concept of life cycle planning. This paper aims to provide explicit and systematic methodologies for life cycle planning by reviewing this research area. Practical cases that employ life cycle planning are also illustrated. Finally, some research directions are suggested. 相似文献
1000.
Heiring Christoph; Muller Yves A. 《Protein engineering, design & selection : PEDS》2001,14(3):183-188
The production of recombinant proteins in Escherichia coli oftenleads to the formation of inclusion bodies. Although this hasa number of advantages, a major disadvantage is the need todevelop folding protocols for the renaturing of the proteins.However, the systematic screening of folding conditions is oftenhampered by the lack of convenient assays to detect correctlyfolded proteins. To address this problem we present a simpleprotocol, which combines folding screens and limited proteolysisto rapidly assess and optimize folding conditions. The efficacyof this method, termed FSAP (folding screening assayed by proteolysis),is demonstrated by the large-scale folding, purification andcrystallization of various cystine deletion mutants of the cystineknot family member: vascular endothelial growth factor (VEGF).These mutants are particularly difficult to fold as the cystineknot is believed to make major contributions to the stabilityof the protein and this family of proteins lacks extensive hydrophobiccore regions. 相似文献