Characterizing the mechanical parameters of forward and backward falls as experienced in snowboarding     

Schmitt KU  Wider D  Michel FI  Brügger O  Gerber H  Denoth J 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(1):57-72

Wrist injuries are frequently observed after falls in snowboarding. In this study, laboratory experiments mimicking forward and backward falls were analysed. In six different falling scenarios, participants self-initiated falls from a static initial position. Eighteen volunteers conducted a total of 741 trials. Measurements were taken for basic parameters describing the kinematics as well as the biomechanical loading during impact, such as impact force, impact acceleration, and velocity. The effective mass affecting the wrist in a fall also was determined. The elbow angle at impact showed a more extended arm in backward falls compared to forward falls, whereas the wrist angle at impact remained similar in forward and backward falls. The study results suggest a new performance standard for wrist guards, indicating the following parameters to characterize an impact: an effective mass acting on one wrist of 3-5 kg, an impact angle of 75 degrees of the forearm relative to the ground, and an impact velocity of 3 m/s.  相似文献   

Structural Equations and Causal Explanations: Some Challenges for Causal SEM     

Keith A. Markus 《Structural equation modeling》2013,20(4):654-676

One common application of structural equation modeling (SEM) involves expressing and empirically investigating causal explanations. Nonetheless, several aspects of causal explanation that have an impact on behavioral science methodology remain poorly understood. It remains unclear whether applications of SEM should attempt to provide complete explanations or partial explanations. Moreover, it remains unclear what sorts of things researchers can best take as causes and effects. Finally, the meaning of causal assertions itself remains poorly understood. Attempting to clarify the use of structural equations as causal explanations by addressing these issues has implications for behavioral science methodology because applications of SEM typically remain vague about causation and thus about their substantive conclusions. Research aimed at clarifying these issues can lead to a sharper and more refined use of SEM for causal explanation, and by extension, clarify behavioral science methodology more generally.  相似文献   

Governance for system optimization and system change: The case of urban waste     

Markus M. Bugge  Arne Martin Fevolden  Antje Klitkou 《Research Policy》2019,48(4):1076-1090

This paper analyses urban waste systems to explore how local authorities can resolve challenges related to climate change, urbanization and resource depletion. The paper investigates how different public governance regimes affect local authorities’ ability to move upwards in the waste hierarchy. It identifies three different governance regimes – traditional bureaucracy, new public management and networked governance – and uses the insights from innovation in urban waste in three Norwegian city regions – Oslo, Drammen and Bergen – to illuminate how these regimes possess both strengths and weaknesses in how they affect system optimization and system change. The observed working practices signal that the issue of urban waste systems is perceived as a challenge of system optimization rather than system change. Viewing this as a challenge requiring system change would probably have ensured a stronger directionality and a broader anchoring of actors. Such an approach is likely to have arrived at a waste prevention mode earlier than the step-by-step-solutions implemented so far. The paper concludes that there is not one best governance regime, but a need to acknowledge their co-existence and carefully consider the characteristics of the respective regimes in order to arrange urban waste systems for long-term dynamic and sustainable city regions.  相似文献   

Measuring patent assessment quality—Analyzing the degree and kind of (in)consistency in patent offices’ decision making   总被引：1，自引：0，他引：1  

Paul F. Burke  Markus Reitzig 《Research Policy》2007,36(9):1404-1430

We argue that consistent decision making in judging a patent's validity and basing this on its underlying technological quality are important elements of patent office service (“assessment”) quality. To understand which level of assessment quality patent offices (can) provide, particularly in new technological areas, we study the concordance of the European Patent Office's (EPO) granting and opposition decisions for individual patents. Using the biotechnology industry in the 1980s (an emerging patenting area then) as an example, we find no empirical evidence that the EPO provided maximal or optimal assessment quality as far as can be told from bibliographic indicators. We discuss research limitations and consequences of this first empirical analysis, and suggest ideas for refinements in future work.  相似文献   

Positive beliefs about errors as an important element of adaptive individual dealing with errors during academic learning     

Maria Tulis  Gabriele Steuer  Markus Dresel 《教育心理学》2018,38(2):139-158

Research on learning from errors gives reason to assume that errors provide a high potential to facilitate deep learning if students are willing and able to take these learning opportunities. The first aim of this study was to analyse whether beliefs about errors as learning opportunities can be theoretically and empirically distinguished from adaptive reactions to errors in an affective-motivational sense (including the maintenance of motivation and activating emotions), and in terms of learning behaviour and metacognitive activities specifically adjusted in response to a specific error. The second aim was to validate the proposed distinction across different domains. The third aim was to investigate the added value of beliefs about errors besides domain-specific self-concept and mastery goal orientation for understanding the preconditions for adaptive reactions to errors at school. We assessed all variables in three different school subjects (N = 614 students, Grades 5–7). Confirmatory factor analyses indicated distinctness and a moderate domain specificity of error-related reactions. Positive error-related beliefs predicted students’ affective-motivational and action adaptivity of error reactions, above and beyond self-concepts and goal orientations. Taken together, the current findings provide a more complete understanding of the intra-personal mechanisms of adaptive responses to errors in different school subjects.  相似文献   

Prediction of elementary mathematics grades by cognitive abilities     

Hilbert  Sven  Bruckmaier  Georg  Binder  Karin  Krauss  Stefan  Bühner  Markus 《European Journal of Psychology of Education - EJPE》2019,34(3):665-683

European Journal of Psychology of Education - In the present study, the relationship between the mathematics grade and the three basic cognitive abilities (inhibition, working memory, and...  相似文献   

Work experience in relation to study pace and thesis grade: investigating the mediating role of student learning     

Tarja Tuononen  Anna Parpala  Markus Mattsson  Sari Lindblom-Ylänne 《Higher Education》2016,72(1):41-58

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Exploring the role of logographemes in Chinese handwritten word production     

Damian  Markus F.  Qu  Qingqing 《Reading and writing》2019,32(1):147-173

Reading and Writing - Recent research has demonstrated that abstract orthographic representations such as morphemes, syllables, and graphemes, influence handwritten production in languages with...  相似文献   

II. Method Overview     

Daniel R. Anderson  Aletha C. Huston  Kelly L. Schmitt  Deborah L. Linebarger  & John C. Wright 《Monographs of the Society for Research in Child Development》2001,66(1):10-24

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Early childhood television viewing and adolescent behavior: the recontact study   总被引：5，自引：0，他引：5  

Anderson DR  Huston AC  Schmitt KL  Linebarger DL  Wright JC 《Monographs of the Society for Research in Child Development》2001,66(1):I-VIII, 1-147

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