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911.
912.
Felix M. Simon 《The Information Society》2019,35(3):158-169
Data-driven campaigning has been in the spotlight over several years. Yet, we still have a limited understanding of political data analytics companies: how they envision data analytics and voter targeting, their role in electoral processes and what promises they make to their clients. This article focuses on the way in which such issues are conceived of in the marketing rhetoric of the political data analytics industry. Drawing on a sample of 19 political data analytics companies it systematically explores the ways in which data analytics is envisioned and marketed as a powerful tool in electoral processes, exposing a fundamental disconnect between scholarly discourse on the one hand – often critical of the claims of these companies about the efficacy of their methods – and a highly functionary data imaginary on the other hand, actively fostered by the political data-analytics industry and the media. 相似文献
913.
Yi-Yuan Li Sara Ying Zhang Jason Zheng Jiang Simon Neild 《Journal of The Franklin Institute》2019,356(14):7836-7854
Vibration suppression capabilities of linear passive vibration absorbers, such as traditional tuned mass damper (TMD), and recently proposed inerter-based vibration absorbers, have been studied for multiple mechanical systems. In particular, significant performance advantages have been obtained with a specific device making use of both inerter and mass elements, namely the tuned mass damper inerter (TMDI). However, there are still countless mass-included inerter-based configurations that have not been studied, which can potentially provide more preferred dynamic properties. In this paper, an immittance-function-layout (IFL) is introduced, which can cover a large range of topological connection possibilities with both mass and inerter elements. With the recently proposed structural immittance format, a systematic approach is established to identify the most beneficial IFL type mass-included inerter-based configurations with pre-determined number of each element type. Vibration suppression performance with single-IFL type device and two parallel-connected IFLs (i.e. dual-IFL) type devices are investigated in this paper. Three optimal configurations are identified for mitigating the maximum inter-storey drift of an example 3-storey building model subjected to base excitation. With this 3-storey building model, results show that, for the optimum single-IFL configuration, the performance improvement is 7.3% compared with the optimum TMDI, and with identified beneficial dual-IFL configurations, up to 34.9% performance advantages are obtained. Furthermore, consistent performance gains are shown under real-life earthquake inputs and with a 10-storey building model using identified absorber configurations. 相似文献
914.
Ann Blandford Anne Adams Simon Attfield George Buchanan Jeremy Gow Stephann Makri Jon Rimmer Claire Warwick 《Information processing & management》2008
The strongest tradition of IR systems evaluation has focused on system effectiveness; more recently, there has been a growing interest in evaluation of Interactive IR systems, balancing system and user-oriented evaluation criteria. In this paper we shift the focus to considering how IR systems, and particularly digital libraries, can be evaluated to assess (and improve) their fit with users’ broader work activities. Taking this focus, we answer a different set of evaluation questions that reveal more about the design of interfaces, user–system interactions and how systems may be deployed in the information working context. The planning and conduct of such evaluation studies share some features with the established methods for conducting IR evaluation studies, but come with a shift in emphasis; for example, a greater range of ethical considerations may be pertinent. We present the PRET A Rapporter framework for structuring user-centred evaluation studies and illustrate its application to three evaluation studies of digital library systems. 相似文献
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It is common for the physiological working capacity of a triathlete when cycling and running to be assessed on two separate days. The aim of this study was to establish whether an incremental running test to exhaustion has a negative effect after a 5 h recovery from an incremental cycling test. Eight moderately trained triathletes (age, 26.2 +/- 3.4 years; body mass, 67.3 +/- 9.1 kg; VO2max when cycling, 59 +/- 13 ml x kg x min(-1); mean +/- s) completed an incremental running test 5 h after an incremental cycling test (fatigue) as well as an incremental running test without previous activity (control). Maximum running speed, maximal oxygen uptake (VO2max) and the lactate threshold were determined for each incremental running test and correlated with the average speed during a 5 km run, which was performed immediately after a 20 km cycling time-trial, as in a sprint triathlon. There were no significant differences in maximum running speed, VO2max or the lactate threshold in either incremental running test (control or fatigue). Furthermore, good agreement was found for each physiological variable in both the control and fatigue tests. For the fatigue test, there were significant correlations between the average speed during a 5 km run and both VO2max expressed in absolute terms (r = 0.83) and the lactate threshold (r = 0.88). However, maximum running speed correlated most strongly with the average speed during a 5 km run (r = 0.96). The results of this study indicate that, under controlled conditions, an incremental running test can be performed successfully 5 h after an incremental cycling test to exhaustion. Also, the maximum running speed achieved during an incremental running test is the variable that correlates most strongly with the average running speed during a 5 km run after a 20 km cycling time-trial in well-trained triathletes. 相似文献
920.
William E. Simon 《Academic Questions》1988,1(4):72-74
This essay originally appeared in the July 8, 1988 issue ofThe Wall Street Journal. It is reprinted here with theJournal's permission. 相似文献