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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   
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Editorial     
This issue of the Journal contains three interesting articlesabout central aspects of public opinion research, as well asan equal number of research notes that reflect the range oftopics that interest all public opinion researchers. Toshio Takeshita takes a turn at reconceptualizing agenda-settingstudies, using a taxonomy  相似文献   
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Zusammenfassung Mit den XML-basierten Sprachen GML, XSLT und SVG lassen sich Geodaten nicht nur anwendungsorientiert modellieren, sondern auch karten?hnlich visualisieren. In dieser Fallstudie zeigen wir das, indem wir realistische Geodatenbest?nde der Landesvermessungs?mter zun?chst mit der Geography Markup Language (GML) nachmodellieren. So mit GML strukturierte Daten werden dann mit der Extensible Stylesheet Language for Transformation (XSLT) auf Elemente der Sprache Scalable Vector Graphics (SVG) abgebildet. Dabei wird der Prozess der kartografischen Visualisierung durch XSLT-Konstrukte modelliert und auch gleichzeitig implementiert. Als Ergebnis erhalten wir Grafiken, die den entsprechenden Karten der Landes?mter zumindest nicht un?hnlich sind.
Using the XML-based languages GML, XSLT and SVG, we modeled German geo data and also visualized it in map-like graphics. This case study shows the feasibility of that approach, by modelling the data with the Geography Markup Language (GML). Then, the GML-structured data is mapped with the Extensible Stylesheet Language for Transformation (XSLT) to elements of the language Scalable Vector Graphics (SVG). The process of cartographical visualization is thus modelled through XSLT-constructs and at same time also implemented. The results are graphics, which share close ressemblance to the corresponding maps of the official offices.
CR Subject Classification I.3.3,I.3.5,I.6.5,I.7.2,J.2  相似文献   
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This study assessed the feasibility of doing hearing screening in Migrant, American Indian and Early Head Start programs using otoacoustic emissions (OAE) technology. Staff members were trained to screen 0–3-year-old children for hearing loss using hand-held OAE equipment and a multi-step screening and referral protocol. Of the 3486 children screened as a part of the study, 77% passed an OAE screening at the first step, 18% more passed an OAE screening at the second step, and 5% were ultimately referred for medical or audiological follow-up. Eighty children were identified as having a hearing loss or disorder of the outer, middle or inner ear requiring treatment. Of these 80, six had permanent bilateral or unilateral hearing loss. Although the protocol suggested that the multi-step screening procedure should be completed within a 4-week time period or less, analysis of the data showed that for children requiring more than an initial OAE screening, the length of time over which the screening was completed ranged from 7 to 12 weeks. The median time required to complete a single OAE screening session was 4 minutes per child. The results demonstrate that OAE screening of young children using this protocol is practical and effective. The implications for conducting periodic hearing screening throughout early childhood are discussed.  相似文献   
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Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to 30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications.  相似文献   
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Data from both neuropsychological and neuroimaging studies have implicated the left inferior parietal cortex in calculation. Comparatively less attention has been paid to the neural responses associated with the commission of calculation errors and how the processing of arithmetic errors is modulated by individual differences in mathematical competence. Do more competent individuals exhibit a different brain response to errors than less mathematically able individuals? These outstanding questions were addressed in the present functional Magnetic Resonance Imaging (fMRI) study through an investigation of which brain regions respond more to erroneously versus correctly solved arithmetic problems while a group of 24 adult participants with varying levels of mathematical competence solved problems of all four arithmetic operations. Despite high levels of accuracy, a robust main effect of accuracy (incorrect vs. correct) was observed in both medial and lateral regions of the prefrontal cortex. These regions have frequently been associated with both the detection of errors and the deployment of cognitive control following an error. Furthermore, mathematical competence was found to modulate the activation of an area in the right dorsolateral prefrontal cortex. Specifically, individuals with relatively higher mathematical competence (n = 12) were found to activate this region more for incorrectly solved trials than their less mathematically competent peers (n = 12). Taken together, these findings suggest that the commission of arithmetic errors modulates responses of prefrontal regions and, moreover, that activation of the right lateral prefrontal cortex during arithmetic errors is affected by individual differences in mathematical competence. In view of the evidence associating the lateral prefrontal cortex with the implementation of cognitive control, we suggest that individuals with relatively high mathematical competence may exhibit greater awareness of calculation mistakes and implement greater control following the commission of errors.  相似文献   
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Being active in civic organizations can be expressed in multifarious forms of participation and commitment. With regard to individuals, the learning context it provides fosters personal development, sympathy for other perspectives, and social competencies in general and is, thus, particularly meaningful for young people in their second and third decades. With regard to organizations, civic participation strengthens the integration and dynamic adaptation of institutions to changing environments and, on a macro-level, raises social cohesion. The contexts of participation are various: not only in educational institutions and the world of work, but also in clubs, organizations and less formal groups, which are involved in social and political issues. Socio-structural and motivational factors, but also belonging to social networks determine the involvement in such forms of civic participation. Additionally, there is evidence of a mutual reinforcement of participation in different contexts. This is shown by the results of the DJI-Survey AID:A 2009.  相似文献   
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