1,720,972 research outputs found
The influence of bicycle fork bending on brake control
No full textBicycle forks are prone to bending, introducing a flexible structure between front wheel and vehicle body. This has substantial influence on brake control, not only by altering the system dynamics but also causing serious estimation problems. These consist in considerable measurement errors in the incremental wheel speed and longitudinal tyre velocity signals, both affecting the wheel slip estimation. This paper provides an in-depth analysis of this problem that represents a profound difference to classical vehicle dynamics. For this purpose, measurements are recorded in test manoeuvres using an extensive set of measurement variables. Based on this data, the complex nonlinear couplings of longitudinal and vertical dynamics are included in a full-vehicle multibody model. The measurement errors as well as compensation methods are evaluated using both simulation and experimental data. In order to examine the influence on closed-loop brake control a linear control-oriented model is derived. Finally numerical full-vehicle simulations show the influence of fork bending on discrete anti-lock brake control systems (ABS), distinguishing the sheer dynamic phenomenon and the related estimation problem
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Modeling of coupled vertical and longitudinal dynamics of bicycles for brake and suspension control
No full textOn vehicles there exists a close coupling between brake and suspension dynamics, making semi-active damper control a promising way for brake maneuver optimization, which has been widely researched in the automotive and motorcycle field. Experimental data of bicycle dynamics analyzed in this paper show substantial differences to classical vehicle dynamics. By first-principle control-oriented modeling and full vehicle nonlinear multibody simulation it is shown that this can be traced back to two phenomena: the dynamic rider response and fork bending. These are very general effects, but crucial for vehicle dynamics control on bicycles, one of the most widely used means of transportation
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Semi-active suspension control on bicycles: Anti-dive during road excitation
No full textSuspension systems on bicycles have a tendency to severe brake-induced dive-in, caused by the small wheelbase in combination with a high center of gravity. Semi-active dampers allow the implementation of anti-dive functionality, preventing this behavior. Experimental analysis has shown that this yields significant advantages during brake control on level surfaces. In the presence of additional road excitation, however, a strong conflict arises. A specific test case is a bump occurring while braking, when the damping is set to the hardest value in order to mitigate dive-in. A simulative analysis illustrates that especially the dynamic wheel load is affected, which during braking is safety critical. By simulation and experimental implementation it is shown that using a simple semi-active control rule a decent trade-off can be found. Finally, the influence of the actuator response time is evaluated
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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