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991.
Whether supervision of doctoral students is best pursued individually or collectively is a recurring but unresolved question in debates on higher education. The rarity of longitudinal data and the common usage of qualitative methods to analyse a limited number of cases have left the effectiveness of either model largely untested. To assist with overcoming these problems, this paper reports on a study of 145 individuals admitted to a specific doctoral programme between 1991 and 2014. It analyses the effects of either individual or collective supervision during the first year of the programme on the probability of thesis completion and the time to thesis completion. Group means, Cox regressions, Kaplan–Meir curves and Ordinary Least Square regressions are calculated on the basis of the number of months spent by each doctoral student in the programme without defending a thesis. Studied in these ways, it appears that collective supervision in the first year significantly increases the probability of thesis completion and decreases the time to thesis completion. Collective supervision may have this effect as it enhances peer learning, creates a wider academic learning context, allows doctoral students to gradually acquire the values and behaviours of a research practice community and reduces the risk of premature selection of permanent supervisors. 相似文献
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Many universities have developed large-scale interdisciplinary research centers to address societal challenges and to attract the attention of private philanthropists and federal agencies. However, prior studies have mostly shown that interdisciplinary centers relate to a narrow band of outcomes such as publishing and grants. Therefore, we shift attention to include outcomes that have been the centers mandate to influence ? namely outreach to the media and private industry, as well as broader research endeavors and securing external funding. Using data covering Stanford University between 1993 and 2014, we study if being weakly and strongly affiliated with interdisciplinary centers in one year relates to and increases (1) knowledge production (publications, grants and inventions), (2) instruction (numbers of students taught, PhDs and postdocs advised), (3) intellectual prominence (media mentions, awards won and centrality within the larger collaboration network), and (4) the acquisition of various sources of funding in the next year. Our results indicate that interdisciplinary centers select productive faculty and increase their activity on a broad range of outcomes further, and in ways greater than departments and traditional interdisciplinary memberships, such as courtesy and joint appointments. 相似文献
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One of the tests used to evaluate the performance of sports surfaces measures the peak deceleration of a rigid mass during
contact with the surface, after being dropped from a set height. It is widely used and is included in a number of international
standards.
The test was carried out using two drop heights on four different designs of artificial cricket pitch, with a full set of
acceleration data being collected over the duration of impact. These data were then integrated twice with respect to time
to produce velocity and displacement information. Oblique impacts of cricket balls were also carried out and analysed using
a high-speed video system to evaluate the playing performance of each pitch design.
It was found that, although the pitches gave quite different readings of peak deceleration, they produced similar values for
coefficient of restitution and were therefore considered to ‘play’ in a very similar way. This was due to a high peak deceleration
reading being accompanied by a short contact time and low peak deceleration being accompanied by a long contact time, meaning
that the change in momentum was similar in both cases. It was concluded that for accelerometer tests to be useful, all the
acceleration-time data should be analysed, rather than the peak value alone. 相似文献
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