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141.
While a good deal of research has examined the uses of Twitter in journalism, comparably few research projects employ comparative research designs in order to provide new insights. The present study details Twitter use by public service broadcasters (PSBs) during recent national elections in Norway and Sweden. Utilizing quantitative analysis of social media content in tandem with qualitative interviews with key PSB journalists, the main results indicate that while the PSB organizations—the Norwegian NRK and the Swedish SVT—are both frequently contacted by “regular” citizens on Twitter, they seem to prefer to retweet and interact with journalists, politicians or other “elite” users. Compared with the interviews performed, the study uncovers an interesting tension as journalists often talk about the need to engage with “regular” users—a practice that is arguably in line with PSB regulations, but that is seldom adhered to in the contexts studied here.  相似文献   
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In the context of strength training in rehabilitation, visual movement control can be helpful to ensure correct movements. However, there are only a few studies that deal with the effectiveness of feedback during resistance exercises. To investigate the effect of feedback during guided exercise, 18 young adults (28.8?±?5.5 years) and 12 senior citizens (67.9?±?4.1 years) were tested. Subjects performed shoulder press exercises (3 sets, 15 repetitions) with and without visual movement control in a randomized order. On day 1, the subjects trained without load, and on day 2 they trained at 50% of their single repetition maximum. Joint articulation at the elbow was recorded using elbow extension and flexion. Autocorrelation was used to determine the reproducibility of movements. Subjects achieved better reproducibility of the movement with feedback than without (χ2?=?19.73; p?<?0.001). There was no effect of the load on motion accuracy (p?>?0.05), but the age group showed a significant effect (χ2?=?6.00; p?=?0.014). The younger group shows a higher degree of movement accuracy. In summary, visual movement control is useful in guided exercises to control movement execution. In clinical setting, this may be a way to control the motion performance of guided strength exercises and to ensure purposeful muscle work. Further studies should clarify the effect of visual feedback on the movement quality in unguided strength exercises.  相似文献   
144.
Extracurricular sport is coupled with many socialization and education potentials for developmental promotion of children and adolescents. The promotion concept “Psychosocial resources in sports” (Sygusch 2007) provides the starting point for the development of capabilities to react and perform in sports as well as for general personality development through sport. This incentive concept is oriented towards training and competitive routine as well as on concrete demands from types of sport. Among others it justifies the methodical measures for promotion of selected resources (e. g. self-concept, cooperative ability). Within the framework of the accompanying study PRimus (psychosocial resources in youth sports) an evaluation of the execution of the programme was realized. Among others it was investigated whether the incentive concept can be implemented in organized child and youth sports. The results indicate that the incentive concept “pedagogically arranged extracurricular youth sports” is implemented by voluntary youth trainers in most instances and is estimated by trainers to be feasible.  相似文献   
145.
Multimedia-Anwendungen und Animationen sind durch Dynamik gekennzeichnet. Die Dynamik muss sich in der Architektur der Anwendung niederschlagen. Eine M?glichkeit hierbei besteht darin, die Dynamik in einer speziellen Softwareschicht innerhalb einer Mehrschichtenarchitektur zu realisieren. Dieses Papier stellt ein Animations-Framework in Java vor, das diese Architektur JavaBeans-konform als muster-orientiertes Framework realisiert und somit die systematische Entwicklung von animierten Multimedia-Anwendungen in Java unterstützt.  相似文献   
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Zusammenfassung Seit der Einführung von Use Cases hat deren Bedeutung zur Spezifikation von Anforderungen stetig zugenommen. Die Qualit?t der Use Cases ist ein entscheidender Faktor für den Erfolg des Entwicklungsprozesses, da die meisten Entwicklungsschritte auf den Use Cases aufbauen. Trotz der extremen Wichtigkeit der Qualit?t der Use Cases stellen die meisten use-case-basierten Entwicklungsans?tze keine oder nur unzureichende integrierte qualit?tssichernde Ma?nahmen bereit (z.B. ad-hoc Empfehlungen, Erstellungsrichtlinien, einige Checklisten zur Inspektion von Use Cases). Diese Techniken werden in den meisten F?llen unabh?ngig voneinander eingesetzt, so dass bestimmte Fehlerklassen in den Use Cases durch mehrere Techniken, andere Fehlerklassen überhaupt nicht adressiert werden. In diesem Artikel wird ein integrierter Ansatz vorgestellt, in dem Use Case Erstellungsrichtlinien, Inspektionen und Simulation in systematischer Weise miteinander verknüpft werden. Der Ansatz basiert auf einer Fehlerklassifikation für Use Cases, die als Grundlage dient, die verschiedenen Techniken auf bestimmte Fehlerarten zu fokussieren .
Since their introduction, use cases (UCs) have become increasingly important for the specification of software requirements. High quality UCs are a prerequisite for project success. Despite the high importance of their quality, UC driven approaches often lack systematic and integrated quality assurance techniques. Only ad-hoc recommendations, creation guidelines, and a few checklists for inspection are available in the literature. If at all, these techniques are developed and used separately, so that one class of defects is addressed by several techniques and other classes are not addressed at all. In this paper, we present an integrated approach that combines UC creation guidelines, UC inspections, and simulation in a systematic way. We base our combined approach on a defect classification for use cases. This classification enables the requirements engineer to focus the different techniques on different types of defects.
CR Subject Classification D2.1  相似文献   
148.
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.  相似文献   
149.
This study used accelerometer and self-report measures of overall sedentary time (ST) and screen time behaviours to examine their respective associations with adiposity among UK youth. Participants (Year groups 5, 8, and 10; n=292, 148 girls) wore the SenseWear Armband Mini accelerometer for eight days and completed the Youth Activity Profile, an online report tool designed to estimate physical activity and ST.Stature, body mass and waist circumference were measured to classify adiposity outcomes (overweight/obese and central obesity). One-way between groups ANOVA and adjusted linear, logistic and multinomial logistic regression analyses were conducted. There was a significant main effect of age on total ST across the whole week (F(2, 289)=41.64, p≤0.001). ST increased monotonically across Year 5 (581.09±107.81 min·dˉ¹), 8 (671.96±112.59 min·dˉ¹) and 10 (725.80±115.20 min·dˉ¹), and all pairwise comparisons were significant at p≤0.001. A steep age-related gradient to mobile phone use was present (p≤0.001). ST was positively associated with adiposity outcomes independent of moderate-to-vigorous intensity physical activity (MVPA; p≤0.001). Engaging in >3 hours of video gaming daily was positively associated with central obesity (OR=2.12, p≤0.05) but not after adjustment for MVPA. Results further demonstrate the importance of reducing overall ST to maintain healthy weight status among UK youth.  相似文献   
150.
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