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1.
Wolfgang Wahlster J?rg Baus Christian Kray und Antonio Krüger 《Informatik - Forschung und Entwicklung》2001,16(4):233-241
Zusammenfassung. Die intelligente Ressourcenadaption ist eine der gro?en Herausforderungen für die n?chste Generation mobiler Navigationssysteme.
Da man typischerweise mehrere Fortbewegungsarten oder Verkehrsmittel kombinieren muss, um an einen Zielort zu gelangen, muss
sichergestellt werden, dass mobile, allgegenw?rtige Navigationshilfen dies über eine jeweils situationsangepasste Benutzerschnittstelle
unterstützen. Der notwendige Wechsel zwischen verschiedenen Positionierungstechnologien soll für den Endbenutzer m?glichst
unbemerkt bleiben. Im folgenden wird ein hybrides Personennavigationssystem vorgestellt, das die in bestimmten Fortbewegungssituationen
verfügbaren Positionierungstechnologien und deren Genauigkeit optimal nutzt, um die Pr?sentation der Wegbeschreibung auf verschiedene
Endger?te und Ausgabemodalit?ten sowie die kognitive Ressourcenlage des Benutzers zu adaptieren.
Eingegangen am 28. Februar 2001 / Angenommen am 8. August 2001 相似文献
2.
Farideh Fekrsanati Stefan Klein Jens Hildenhagen Klaus Dickmann Yiorgos Marakis Aleka Manousaki Vassilis Zafiropulos 《Journal of Cultural Heritage》2001,2(4):187
The application of lasers for the removal of superficial deposits from historic stained glass is a comparatively new field of scientific interest. Experimental studies concerning the behaviour of glass substrates and the corresponding superficial deposits towards different laser wavelengths were carried out. The experiments were performed using wavelengths of λ = 193 nm (ArF-Excimer), 308 nm (XeCl-Excimer), 355 nm (Nd:YAG third harmonic) and 1 064 nm (Nd:YAG fundamental) in comparison to λ = 248 nm (KrF-Excimer). This comparison is due to the fact that the present knowledge is based on the 248 nm wavelength. Specially prepared model glass samples representing the original fragments and samples of organic polymers (formerly used as a protective material for historic stained glasses) were used to study the effects of laser radiation and were subsequently characterised by optical microscopy. 相似文献
3.
Zusammenfassung Diese Arbeit stellt ein Modell und ein System zur Steuerung von Exoskeletten mit Hilfe von elektrischen
Signalen vor, die an den Muskeln des Benutzers gemessen werden. Anhand dieser Signale wird der eigene Drehmomentbeitrag
des Benutzer zur gewünschten Bewegung abgesch?tzt, und ein einstellbarer Faktor bestimmt das vom
Exoskelett hinzugefügte Drehmoment in Bezug auf den Beitrag des Benutzers. Die Signale werden durch
ein komplexes biomechanisches Modell ausgewertet.
CR subject classification J.3 ; J.7 ; I.6.5 相似文献
4.
Christian von Sikorski 《Communication Research Reports》2018,35(2):162-171
Reports about political scandals have increased lately. Yet the general impact of news visuals and the specific role of lightness and darkness cues in images of scandalized politicians remain unclear. With the help of an experiment, the present pilot study examined the influence of candidate images and the effects of particular image backgrounds (light versus dark). While the foreground of the image depicting a politician involved in a scandal remained unchanged, the background was systematically altered. The results revealed that a light background had a positive effect on recipients’ attitudes toward the politician. In contrast, participants exposed to a dark image background demanded a more severe punishment for the politician. 相似文献
5.
Many studies demonstrate differences in the coverage of citing publications in Google Scholar (GS) and Web of Science (WoS). Here, we examine to what extent citation data from the two databases reflect the scholarly impact of women and men differently. Our conjecture is that WoS carries an indirect gender bias in its selection criteria for citation sources that GS avoids due to criteria that are more inclusive. Using a sample of 1250 U.S. researchers in Sociology, Political Science, Economics, Cardiology and Chemistry, we examine gender differences in the average citation coverage of the two databases. We also calculate database-specific h-indices for all authors in the sample. In repeated simulations of hiring scenarios, we use these indices to examine whether women's appointment rates increase if hiring decisions rely on data from GS in lieu of WoS. We find no systematic gender differences in the citation coverage of the two databases. Further, our results indicate marginal to non-existing effects of database selection on women's success-rates in the simulations. In line with the existing literature, we find the citation coverage in WoS to be largest in Cardiology and Chemistry and smallest in Political Science and Sociology. The concordance between author-based h-indices measured by GS and WoS is largest for Chemistry followed by Cardiology, Political Science, Sociology and Economics. 相似文献
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8.
In this article, we build on Stigler and Becker’s (1977) “consumption capital theory” and propose a novel conceptualization of film quality for the analysis of motion picture franchises. Generally, this theory predicts that the utility consumers derive from a particular good or service increases with prior consumption. We test our theoretical conjectures by drawing on the population of sequels that were running in the US between 1992 and 2011. The empirical results point to the explanatory power of the proposed framework. Film executives may use our findings to improve the profitability of their sequel productions. From a theoretical point of view, consumption capital theory allows for a more refined analysis of sequel performance along different dimensions. Moreover, it may provide a fruitful basis for the analysis of other serial media content, including books, TV, music, and games. 相似文献
9.
Hui-ping Lin Jun Lin Juan Li Jing-hong Xu Christian Mehl 《Journal of Zhejiang University. Science. B》2016,17(11):864-873
Resin-dentin bond degradation is a major cause of restoration failures. The major aim of the current study was to evaluate the impact of a remineralization medium on collagen matrices of hybrid layers of three different adhesive resins using nanotechnology methods. Coronal dentin surfaces were prepared from freshly extracted premolars and bonded to composite resin using three adhesive resins (FluoroBond II, Xeno-III-Bond, and iBond). From each tooth, two central slabs were selected for the study. The slabs used as controls were immersed in a simulated body fluid (SBF). The experimental slabs were immersed in a Portland cement-based remineralization medium that contained two biomimetic analogs (biomineralization medium (BRM)). Eight slabs per group were retrieved after 1, 2, 3, and 4 months, respectively and immersed in Rhodamine B for 24 h. Confocal laser scanning microscopy was used to evaluate the permeability of hybrid layers to Rhodamine B. Data were analyzed by analysis of variance (ANOVA) and Tukey’s honest significant difference (HSD) tests. After four months, all BRM specimens exhibited a significantly smaller fluorescent area than SBF specimens, indicating a remineralization of the hybrid layer (P≤0.05). A clinically applicable biomimetic remineralization delivery system could potentially slow down bond degradation. 相似文献
10.
The FIFA World Cup for men (hereafter referred to as the FIFA World Cup) is possibly the biggest global media event. Winning or losing often gives rise to expressions of collective degrees of national pride or disappointment. But, it is not only the performance of the teams that is of significance in this respect; the devotion of fans to the game and their loyalty to their own national team are also an important vehicle of identity and self-affirmation as a nation. Thus, no country can afford to dispense with the travelling model of the enthusiastic fan as a representative of national identity. Through an ethnographic study of Ghana’s state-financed fan trip to the FIFA World Cup 2010 in South Africa, we will show how the actors involved (government, opposition, fans and media) negotiate national identity and representation. 相似文献