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31.
Alisher Mirzabaev Dawit Guta Jann Goedecke Varun Gaur Jan Börner Detlef Virchow 《国际水》2015,40(5-6):772-790
This article provides a review of trade-offs and synergies of bioenergy within the water–energy–food security nexus, with emphasis on developing countries. It explores the links of bioenergy with food security, poverty reduction, environmental sustainability, health, and gender equity. It concludes that applying the nexus perspective to analyses of bioenergy widens the scope for achieving multiple-win outcomes along the above aspects. 相似文献
32.
33.
Tilmann Beck Karl-Heinz Lang Detlef Löhe 《Transactions of the Indian Institute of Metals》2010,63(2-3):195-202
The influence of superimposed total strain controlled HCF loadings on TMF life is presented and discussed for several cast Al-Si alloys, the Ni-base superalloy Inconel 617 and the cast iron GJS-700. Except for GJS-700, a threshold of the superimposed HCF loading is observed, below of which TMF life is not significantly affected. The strong decrease of TMF life as soon as the HCF amplitude exceeds this threshold is due to fundamental changes in the crack propagation mechanisms. The paper closes with a brief overview on lifetime prediction methods for TMF and their application in the case of TMF/HCF loadings. 相似文献
34.
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
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36.
Sbastien Gentil Eulalia Crespo Isabel Rojo Aurlie Friang Clara Vias Francesc Teixidor Bohumír Grüner Detlef Gabel 《Polymer》2005,46(26):12218-12225
The influence of weakly coordinating anions with different shapes and substituents has been studied to get the overoxidation resistance limit of the material, ORL. The anions utilized are derivatives of [Co(C2B9H11)2]−, [B12H12]2− and [B12H11NH3]−. The following tendencies have been established (1) boron cluster monoanions are to date the anions that offer the highest stability to overoxidation of PPy doped materials (2) the ORL stability of the material can not be attributed only to the shape of the cluster (3) monoanionic clusters are far superior than dianionic to get an ORL rise (4) cluster charge density reduction results in ORL rise as has been observed in [Co(C2B9H11)2]− after incorporation of electron-withdrawing substituents with no electron back-donation (5) globular, rigid and large monoanions are less suitable for enhanced ORL values than elongated and non-rigid species (6) adequate anion's substitution produce a rise in the ORL of the material, thus polyether side-arms are beneficial with [Co(C2B9H11)2]−, whereas, T-shaped methylaryl groups are appealing in [B12H11NH3]− based materials, respectively, (7) substituents on the anions usually imply higher difficulty in the materials' growth. The high boron contents in these materials has permitted to learn on the fate of the doping anions during the overoxidation process. There is a built-up of the concentration of the doping anion in the electrolyte near surface area, whereas, a depletion is observed in the nearest inner layers. 相似文献
37.
38.
Prof. Dr.-Ing. Hans Kurt Tönshoff Dipl.-Ing. Detlef Ahlborn 《Forschung im Ingenieurwesen》1992,58(1-2):1-5
Zusammenfassung Bei der experimentellen Modalanalyse von Maschinen führen Fehler der Frequenzgangmessung und die getroffenen Annahmen bei
der Formulierung der elastomechanischen Gleichungen zu Abweichungen zwischen gemessenen und modellierten Frequenzg?ngen. Im
vorliegenden Beitrag wird ein auf einer linearen Modellierung beruhendes Frequenzbereichsverfahren diskutiert, das eine Absch?tzung
der statistischen Unsicherheiten der dynamischen Modellparameter Eigenfrequenz, D?mpfung und Schwingungsform erlaubt. Es wird
gezeigt, da? bei der Relativerregung eine andere Gleichung für die Parametersch?tzung zu w?hlen ist, als bei der absoluten
Erregung von Maschinen. Wird die Relativerregung im Modell nicht berücksichtigt, treten erhebliche Fehler bei Ermittlung der
Schwingungsformen auf, die exemplarisch diskutiert werden.
Der vorgestellte Bericht ist aus den Arbeiten des von der Deutschen Forschungsgemeinschaft (DFG) gef?rderten Sonderforschungsbereiches
121 „Ger?usch- und Schwingungsvorg?nge an Maschinen” hervorgegangen 相似文献
39.
Detlef Kilian 《Datenschutz und Datensicherheit - DuD》2007,31(3):214-217
Zusammenfassung Nachdem wir unser Augenmerk in den beiden ersten Teilen dieser Reihe auf die bestehenden Standards für Informationssicherheitsmanagementsysteme
(ISMS), deren theoretische Grundlagen und die wichtigsten Unterschiede gerichtet hatten, m?chten wir diesmal zeigen, was bei
der praktischen Implementierung zu beachten ist.
Detlef Kilian ist Senior Consultant, Lehrbeauftragter für IT-Security an der FH Braunschweig/Wolfenbüttel und lizenzierter
Auditor für ISO 27001 Audits auf Basis von IT-Grundschutz des Bundesamtes für Sicherheit in der Informationstechnik (BSI). 相似文献
40.