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131.
Alexandros Gavriilidis Jörg Velten Stephan Tilgner Anton Kummert 《Journal of The Franklin Institute》2018,355(4):2009-2021
Electronic assistance devices for visually impaired people often require pedestrian detection functionality. Due to the fact that these devices have only low computational processing capabilities, it is necessary to use realtime algorithms that meet these requirements.We thus propose application of a cascaded support vector machine (SVM) classifier with linear and combined cascading of SVMs based on histogram of oriented gradients (HOGs) and Fisher score preselection. Proposed algorithms are evaluated on the basis of the INRIA database and compared to the state of the art procedure with HOG-features in combination with a standard SVM. 相似文献
132.
Stephan van der Zwaard Guido Weide Koen Levels Michelle R. I. Eikelboom Dionne A. Noordhof Mathijs J. Hofmijster 《Journal of sports sciences》2018,36(18):2111-2120
Rowers need to combine high sprint and endurance capacities. Muscle morphology largely explains muscle power generating capacity, however, little is known on how muscle morphology relates to rowing performance measures. The aim was to determine how muscle morphology of the vastus lateralis relates to rowing ergometer performance, sprint and endurance capacity of Olympic rowers. Eighteen rowers (12♂, 6♀, who competed at 2016 Olympics) performed an incremental rowing test to obtain maximal oxygen consumption, reflecting endurance capacity. Sprint capacity was assessed by Wingate cycling peak power. M. vastus lateralis morphology (volume, physiological cross-sectional area, fascicle length and pennation angle) was derived from 3-dimensional ultrasound imaging. Thirteen rowers (7♂, 6♀) completed a 2000-m rowing ergometer time trial. Muscle volume largely explained variance in 2000-m rowing performance (R2 = 0.85), maximal oxygen consumption (R2 = 0.65), and Wingate peak power (R2 = 0.82). When normalized for differences in body size, maximal oxygen consumption and Wingate peak power were negatively related in males (r = ?0.94). Fascicle length, not physiological cross-sectional area, attributed to normalized peak power. In conclusion, vastus lateralis volume largely explains variance in rowing ergometer performance, sprint and endurance capacity. For a high normalized sprint capacity, athletes may benefit from long fascicles rather than a large physiological cross-sectional area. 相似文献
133.
The use of weblogs as an information and communication technology for knowledge sharing and creation is a novel social and organizational phenomenon. In this paper, we identify and explain contingency factors that influence the successful use of weblogs for knowledge sharing and creation. We start from the assumption that successful knowledge management requires the motivation of people to engage in knowledge-related communication. Based on a comparison of two antithetic cases, we identify and discuss four contingency factors that directly influence the motivational impact of weblogs on organizational knowledge sharing and creation. 相似文献
134.
Ke Zhu Arseny S. Kaprelyants Elena G. Salina Martin Schuler Gerard H. Markx 《Biomicrofluidics》2010,4(2)
A study of the effect of aggregate size on the resuscitation of dormant M. smegmatis was conducted by constructing cell aggregates with defined sizes and shapes using dielectrophoresis and monitoring the resuscitation process under controlled laboratorial conditions in a long-term cell feeding system. Differently sized cell aggregates were created on the surface of indium tin oxide coated microelectrodes, their heights and shapes controlled by the strength of the induced electric field and the shape of the microelectrodes. Both two-dimensional (ring-patterned) and three-dimensional cell aggregates were produced. The cell aggregates were maintained under sterile conditions at 37 °C for up to 14 days by continuously flushing Sauton’s medium through the chamber. Resuscitation of dormant M. smegmatis was evaluated by the production of the fluorescent dye 5-cyano-2,3-ditolyltetrazolium chloride. The results confirm that the resuscitation of dormant M. smegmatis is triggered by the accumulation of a resuscitation promoting factor inside the aggregates by diffusion limitation. 相似文献
135.
136.
Skedsmo Guri Huber Stephan Gerhard 《Educational Assessment, Evaluation and Accountability》2021,33(4):587-589
Educational Assessment, Evaluation and Accountability - 相似文献
137.
Huber Stephan Gerhard Helm Christoph 《Educational Assessment, Evaluation and Accountability》2020,32(2):237-270
Educational Assessment, Evaluation and Accountability - The crisis caused by the COVID-19 virus has far-reaching effects in the field of education, as schools were closed in March 2020 in many... 相似文献
138.
Suzan Verberne Hans van Halteren Daphne Theijssen Stephan Raaijmakers Lou Boves 《Information Retrieval》2011,14(2):107-132
In this paper, we evaluate a number of machine learning techniques for the task of ranking answers to why-questions. We use TF-IDF together with a set of 36 linguistically motivated features that characterize questions and answers.
We experiment with a number of machine learning techniques (among which several classifiers and regression techniques, Ranking
SVM and SVM
map
) in various settings. The purpose of the experiments is to assess how the different machine learning approaches can cope
with our highly imbalanced binary relevance data, with and without hyperparameter tuning. We find that with all machine learning
techniques, we can obtain an MRR score that is significantly above the TF-IDF baseline of 0.25 and not significantly lower
than the best score of 0.35. We provide an in-depth analysis of the effect of data imbalance and hyperparameter tuning, and
we relate our findings to previous research on learning to rank for Information Retrieval. 相似文献
139.
Age-publishing profiles are estimated for four fields of science using data from the 1977 Survey of Doctorate Recipients. The five measures of publishing activity used allow for analysis of the sensitivity of the age-publishing relationship to output measure. Results are presented separately for graduate faculty and faculty at nongraduate departments. Although age is found to be a fairly weak predictor of performance, in physics and earth science older scientists publish less than their youngest peers and in physiology and biochemistry older scientists publish less than their middle-aged colleagues. Given the time frame of the data, the results suggest that the graying of America's scientific community was accompanied with slowed rates of research in higher education. 相似文献
140.
Manuela Glaser Dominik Lengyel Catherine Toulouse Stephan Schwan 《Educational technology research and development : ETR & D》2017,65(5):1135-1151
In the present study, we investigated the role of digital zoom as a tool for directing attention while looking at visual learning material. In particular, we analyzed whether minimal digital zoom functions similarly to a rhetorical device by cueing mental zooming of attention accordingly. Participants were presented either static film clips, film clips with minimal zoom-ins, or film clips with minimal zoom-outs while eye movements were recorded. We hypothesized that minimal zoom-ins should lead to more gaze coherence, to longer dwell times as an indicator of more elaborative processing, and to fewer transitions as an indicator of less mental integration. Zoom-outs, on the other hand, were expected to have opposite effects. Results showed that zoom-ins increase gaze coherence and dwell times on the center parts of the depictions while decreasing transitions of pictorial elements from the center and the context areas. In contrast, patterns of results from zoom-outs and static presentations were similar to a large degree, indicating that zoom-ins and zoom-outs do not operate in a complementary fashion. Theoretical and practical implications of the present results are discussed. 相似文献