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1.
Wolfgang Schr?der-Preikschat Daniel Lohmann Fabian Scheler Olaf Spinczyk 《Informatik - Forschung und Entwicklung》2007,22(1):5-22
Design, implementation, and re-engineering of operating systems are still an ambitious undertaking.
Despite, or even because, of the long history of theory and practice in this field, adapting existing systems
to environments of different conditions and requirements as originally specified or assumed, in terms of
functional and/or non-functional respects, is anything but simple. Especially this is true for the embedded
systems domain which, on the one hand, calls for highly specialized and application-aware system abstractions
and, on the other hand, cares a great deal for easily reusable implementations of these abstractions.
The latter aspect becomes more and more important as embedded systems technology is faced with an innovation
cycle decreasing in length. Software for embedded systems needs to be designed for variability, and this
is in particular true for the operating systems of this domain. The paper discusses dimensions of variability
that need to be considered in the development of embedded operating systems and presents approaches that
aid construction and maintenance of evolutionary operating systems.
CR subject classification C.3; D.2.11; D.2.13; D.4.7 相似文献
2.
In many countries, studies show declining levels of trust in news media at large. However, there still is no valid and accepted measure of generalized trust in news media. To establish and test a suitable measure, we chose two elaborate scales of related concepts: the scale on trust in media coverage of a specific topic by Kohring and Matthes and a credibility scale by Yale, Jensen, Carcioppolo, Sun, and Liu. We adapted both to measure generalized trust in news media and conducted a survey in Germany to (a) evaluate the dimensional structures of both adapted scales and (b) analyze their predictive validity by testing their explanative power on alternative media use. Both adapted scales yield well-fitting models but should be carefully treated with respect to discriminant validity. The adapted Kohring and Matthes scale successfully predicts alternative media use and can therefore be recommended for further research on generalized trust in news media. 相似文献
3.
Alba E. Mustaca Fabian Gabelli Mauricio R. Papini Peter Balsam 《Learning & behavior》1991,19(2):125-138
Appetitive contextual conditioning in rats and ringdoves was investigated in six experiments. In Experiment 1, differential contextual training produced greater anticipatory activity in rats in the presence of a context paired with food than it did in rats in the presence of a different context in which food was never presented. Furthermore, the rats showed a preference for the context associated with food when they were given a simultaneous choice test between contexts. In Experiment 2, rats were more active in and preferred a context associated with a variable-time 30-sec (VT30) schedule as opposed to a VT180 schedule. Experiment 3 was a between-subjects replication of the previous experiment. As expected, rats exhibited significantly more anticipatory activity in a context in which food had been presented on a VT30 schedule than they did in a context in which food had been presented on a VT180 schedule. Experiment 4 showed that anticipatory activity was a reflection of context-US associations in ringdoves, and in Experiments 5 and 6, ringdoves also exhibited an inverse relationship between the. amount of anticipatory activity and the length of the interreinforcement interval (IRI). These results reveal a relation between ERI and contextual conditioning opposite from that obtained in studies of aversive conditioning. 相似文献
4.
Daniel Aragonés Alexander Eekhoff Fabian Horst Wolfgang Immanuel Schöllhorn 《Journal of sports sciences》2018,36(11):1296-1304
Training consisting of numerous repetitions performed as closely as possible to ideal techniques is common in sports and every-day tasks. Little is known about fatigue-related technique changes that emerge at different timescales when repeating complex actions such as a karate front kick. Accordingly, 15 karatekas performed 600 kicks (1 pre-block and 9 blocks). The pre-block comprised 6 kicks (3 with each leg) at maximum intensity (K-100%). Each block comprised 60 kicks (10 with each leg) at 80% of their self-perceived maximum intensity (K-80%) plus 6 K-100%. In between blocks, the participants rested for 90 seconds. Right leg kinematics (peak joint angles, peak joint angular velocities, peak joint linear resultant velocities, and time of occurrence of peaks) and kick duration corresponding to the K-80% were measured resulting in numerous variations with fatigue. At the timescale of tens of seconds, the changes involved variables that were related to velocity of execution (slowed down), while variables related to movement form were hardly affected. At the timescale of tens of minutes, the opposite results were observed. These findings challenge the long-standing rationale underlying repetitive training, suggesting instead that such involuntary variations in technique might play a crucial role in motor skill training 相似文献
5.
Despite its strong impact in domestic settings on job performance, organizational commitment, stress, and turnover intentions, job satisfaction has received little attention in the literature on expatriates. This paper analyzes the predictors of job satisfaction that may arise in an expatriate context. Drawing on the cultural distance perspective, we propose that the national cultural distance, supervisor's nationality, host-country language proficiency, expatriate type, and company nationality are important determinants of expatriate job satisfaction. Survey results from 148 expatriates in Japan demonstrate that national cultural distance, supervisor's nationality, and expatriate type have a statistically significant influence on expatriate job satisfaction. Theoretical and practical implications are provided. 相似文献
6.
Daniel A. Bizjak Fabian Tomschi Gunnar Bales Elie Nader Marc Romana Philippe Connes Wilhelm Bloch Marijke Grau 《运动与健康科学(英文)》2020,9(6):595-603
ObjectiveTo examine the impact of a 6-week endurance training on red blood cell (RBC) aging and deformability of healthy participants to detect possible improved hemorheological and performance-related adaptations.MethodsA total of 31 participants (17 females and 14 males) performed a 6-week moderate training protocol (three 1-h running sessions per week at 70% of maximal heart rate). Blood was sampled before and after the training. RBCs from each participant were fractioned according to density and age into 4 RBC subfractions. Subfractions were examined for changes of RBC properties, including aging distribution, RBC deformability, RBC microparticles, and phosphatidylserine concentrations. RBC and plasma nitrite levels were measured as indicators of nitric oxide metabolism.ResultsAerobic performance, peak oxygen consumption, ventilatory thresholds, velocity at the aerobic–anaerobic threshold, and lactate at exhaustion improved after training. The relative amount of both young RBCs and old RBCs increased, and the amount of the main RBC fraction decreased. Phosphatidylserine externalization and RBC-derived microparticles decreased. Overall deformability expressed as shear stress required to achieve half-maximum deformation to theoretical maximal elongation index at infinite shear stress improved in unfractioned RBCs (p < 0.001). Nitrite decreased in total (p = 0.001), young (p < 0.001), main (p < 0.001), and old (p = 0.020) aged RBCs and in plasma (p = 0.002), but not in very old RBCs.ConclusionThese results indicate that non-endurance-trained healthy participants benefit from a regular moderate running training program because performance-related parameters improve and a younger RBC population with improved RBC properties is induced, which might support oxygen supply in the microcirculation. 相似文献
7.
Fabian W. Otte Sarah-Kate Millar Stefanie Klatt 《Journal of sports sciences》2020,38(11-12):1465-1473
ABSTRACT The football goalkeeper position arguably represents a unique role within the team sport. Despite its highly complex skill demands, research on football goalkeeping has only sporadically examined the position within isolated and limited parameters. In particular, there is limited literature on “modern” skill acquisition training methods and approaches within the field of goalkeeper training. In a cross-cultural study with fifteen expert goalkeeper coaches, researchers here examined the overarching research question of “how does the modern football goalkeeper train?”. Semi-structured interviews explored expert coaches’ views on critical skills for performance in goalkeeping and the training approaches used to develop these critical skills. Results indicate that four skill sets are considered essential by goalkeeper coaches, these are: decision-making skills, athleticism, mentality, and technical skills. In terms of developing these skills in goalkeeper-specific training, the majority of expert coaches apply a similar microstructure to training sessions. This structure involves a steady progression from simple to complex training tasks, where for large parts, isolated technical training appears to be prioritised over a holistic training approach that integrates technical skills and perceptual-cognitive components (e.g., decision making). Scientific and practical recommendations for researchers and practitioners in the field of football goalkeeper coaching are provided. 相似文献
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ABSTRACTThe present study aims to investigate the ability of a new framework enabling to derive more detailed model-based predictions from ranking systems. These were compared to predictions from the bet market including data from the World Cups 2006, 2010, and 2014. The results revealed that the FIFA World Ranking has essentially improved its predictive qualities compared to the bet market since the mode of calculation was changed in 2006. While both predictors were useful to obtain accurate predictions in general, the world ranking was able to outperform the bet market significantly for the World Cup 2014 and when the data from the World Cups 2010 and 2014 were pooled. Our new framework can be extended in future research to more detailed prediction tasks (i.e., predicting the final scores of a match or the tournament progress of a team). 相似文献
10.
This article aims to provide an overview of the current state of research on the relationship between loneliness and physical activity (PA). A systematic literature search was conducted to identify all empirical studies assessing this relationship. A total of 37 studies stemming from 36 publications met the inclusion criteria. Study analyses comprised an individual consideration of each study and a systematic summarization of the studies. The majority of eligible studies focused on adolescent or elderly populations. Direct negative associations between PA and loneliness were found in half of the 24 cross-sectional studies. Of the seven identified longitudinal studies, one found a direct negative influence of PA on loneliness. Four longitudinal studies found evidence for a reverse influence, namely of loneliness on PA. Five intervention studies found PA to reduce loneliness. Two of the cross-sectional studies and one of the intervention studies found social support and social competence to moderate or to mediate the relationship between PA and loneliness. The findings indicate that PA can contribute to a decrease in loneliness. However, studies also indicate that any beneficial effect is dependent upon the quality of relationships present during physical activity. Additionally, loneliness itself might reduce the probability of being physically active. 相似文献