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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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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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Kevin Hovland and Carol Geary Schneider champion the importance of a twenty‐first‐century liberal education and provide examples of essential learning outcomes that make global and civic learning central and pervasive.  相似文献   
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Factors that influence the incidence of utilization deficiencies and other recall/strategy-use patterns on a strategic memory task were evaluated in two hundred and fourteen 7- and 9-year-old children. Both utilization deficiencies and the incidence of children showing increases in both recall and strategy use over phases were more likely to be observed on phase transitions involving prompting or when different lists of items were included on consecutive trials; in contrast, increases in recall in the absence of increases in strategy use were more likely to be found between trials consisting of the same stimulus items. This research clearly indicates that patterns of recall/strategy-use relations, including utilization deficiencies, vary meaningfully with the age of the child and a variety of contextual factors.  相似文献   
7.
Weighted vests are widely used to improve running economy and performance. However, it is not well-studied how running mechanics are adapted to counteract the higher peak vertical ground reaction forces (Fpeak) while running with such a device. Therefore, the present study aimed to investigate the effects of different loading conditions on running mechanics at different velocities. Thirteen subjects participated in two separate sessions one week apart. In the first session, maximal aerobic speed (MAS) was determined through a maximal incremental running test while in the second session, they were instructed to run during one minute under different loading (0%, +10% and +20% of body mass [BM]) and velocity (60%, 80% and 100% of MAS) conditions in a random order. Spatiotemporal data were recorded and then running mechanics modelled using the spring-mass model. The main results indicated that vertical and leg stiffness (Kvert and Kleg, respectively) were increased (P?P?>?.05) when load was changed. At the same time, alterations of the running kinematics were observed such as longer contact times, reduced flight times, stride frequencies and step lengths, as well as an increase of the centre of mass dynamics. Based on these results it is assumed that runners maintain a certain stiffness level for each velocity despite different loading conditions. As a consequence, Fpeak increases and this probably causes spatiotemporal adjustments in the movement kinematics.  相似文献   
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On 1 August 1929 the Prussian Minister of Education enacted a regulation establishing“exercise and physical education” as an academic field of study to be offered at all universities and institutes of technology under his jurisdiction. This action served to successfully complete the process that had been evolving since the middle of the nineteenth century to recognize the discipline as a university level specialty in the face of considerable longstanding opposition. The gravest forms of opposition emanated from the universities themselves and starting in the middle of the 1920s were ultimately overcome by proceedings and argumentation. These circumstances are described in this contribution based on accessing and evaluating new sources. The central focus is on a memorandum written in February 1929 by the Göttingen University physical education lecturer Bernhard Zimmermann. The article concludes by classifying and assessing the act of 1929 with a view to the further development of the academic education of sports instructors in the ensuing era of National Socialism and the postwar period in West Germany and the Federal Republic of Germany.  相似文献   
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In this paper, I analyze how recent calls to internationalize publication behavior affect research practices at an automotive engineering department in Germany. Automotive engineering is a field with traditionally rather scarce publication activity and strong connections to industry. Substantial authority to define suitable research problems and ways of organizing knowledge production on a daily basis was therefore reserved for local academic elites as well as corporate partners. However, as engineers are increasingly expected to prove their performance through publishing in international peer-reviewed journals, the judgment as to what should be considered “interesting” or “robust” research is partly relegated to a gradually globalizing community of academic peers. This generates a variety of tensions with established ways of coordinating epistemic work at the department studied here. For example, the thematic interests of journals tend to exert a disruptive centrifugal pull in the context of an otherwise highly modular research culture, and possibilities to publish in international venues are unequally distributed across individual research projects. But while department members agree that there is a lack of fit between current practices and new expectations towards their publishing behavior, their opinions about the conclusions that should be drawn differ significantly. Some researchers argue that profound organizational changes are necessary to foster the academic rigor of German engineering research. Others believe that evaluation criteria should simply be adapted. This situation is arguably characteristic for research areas with a traditionally strong orientation to local stakeholders, and it suggests a need for more deliberative, participatory approaches to research evaluation in such fields.  相似文献   
10.
Studying abroad is one way in which university students can develop personal capital and distinguish themselves in an increasingly congested graduate labour market. Data show that studying abroad indeed provides employment benefits, with evidence pointing to even greater positive effects for students from low socio‐economic status backgrounds. Focusing on a group of Canadian students about to embark on a study exchange, we find no evidence that career‐instrumental reasons played a role in participants’ decisions to study abroad. Rather, they sought personal growth and escape from the everyday frustrations of being an undergraduate student. We argue, however, that these motivations nonetheless have to be understood as strategic, since going on a study exchange abroad allows students to escape temporarily, while ‘staying in the game’ of becoming credentialed at home. We discuss the role of socio‐economic status, as well as the policy implications of these findings.  相似文献   
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