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891.
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Rebekka Darner Gougis Janet F. Stomberg Alicia T. O’Hare Catherine M. O’Reilly Nicholas E. Bader Thomas Meixner Cayelan C. Carey 《International Journal of Science and Mathematics Education》2017,15(6):1039-1056
The concepts of randomness and variation are pervasive in science. The purpose of this study was to document how post-secondary life science students explain randomness and variation, infer relationships between their explanations, and ability to describe and identify appropriate and inappropriate variation, and determine if students can identify sources of variation. An instrument designed to test statistical concepts was administered to 282 college students from three universities, ranging from introductory non-science majors to science graduate students. Students readily distinguished between causes of variation. A naïve no-pattern concept of randomness persisted from first-year non-science majors to senior-level science majors, contributing to incorrect responses on the variation instrument. Students’ expressions of randomness were better predictors of performance on the variation instrument than their expressions of variation. It is argued that inclusion of everyday language uses of randomness in instruction can bridge the gap between vernacular and scientific uses of this term. 相似文献
894.
James V. Devine Luther C. Jones Janice W. Neville Dilys J. Sakai 《Learning & behavior》1977,5(1):57-62
Two experiments were performed to determine the effect of sample duration (0.1, 2, and 4 sec), delay interval (.03, 4, 8, 16, and 32 sec), and type of stimulus (color and shape) on the matching performance of rhesus monkeys. In Experiment 1, the 15 possible delay-duration combinations were randomly presented in blocks of 15 trials. In Experiment 2, each duration was held constant and the five delays randomly presented. Then each delay interval was held constant with the three durations randomly varied. Matching performance increased as sample duration increased (ps < .01 and .005), while length of delay did not significantly affect performance. The type of stimuli paired in the matching test significantly affected performance (ps < .05 and .10) with the shape/shape choices leading to the poorest performance. Stimulus discriminability and amount of training with brief sample durations were implicated as significant determinants of matching performance. 相似文献
895.
Cynthia A. Hoffner Yuki Fujioka Jiali Ye Amal G. S. Ibrahim 《Mass Communication and Society》2013,16(2):193-216
This study explored the reasons people expose themselves to news depicting tragic events. A total of 376 undergraduates completed anonymous questionnaires about their responses to news coverage of the events of September 11. The study examined the extent to which individual differences in empathy gave rise to news viewing motives (surveillance, reassurance, curiosity), and how these variables, as well as negative emotional responses (anger, sadness, fear), were related to news interest and exposure. Both empathy and emotional responses were associated in predictable ways with interest in news coverage and selective exposure to specific types of news stories (e.g., casualty news, positive news). The results demonstrate that considering affective motivations can enrich our understanding of how and why people use news media. Limitations and suggestions for future research are discussed. 相似文献
896.
897.
N. M. Builova E. M. Epshtein V. G. Shamaev 《Scientific and Technical Information Processing》2008,35(1):28-29
The necessity for publishing a separate abstract journal on spintronics, which is a new, rapidly developing branch of physics, is substantiated. The interest in spintronics, which is the study of fundamental processes involving the simultaneous transport of both electron charge and electron spins in solids, as well as the interaction of electrons with a magnetic grating, is determined not only by its fascinating prospects but also the results that have already achieved. The spin and charge “degrees of freedom” open possibilities for the creation of semiconducting devices with parameters that are much superior to the existing ones and also the construction of devices that do not have analogues at present. First of all, this will permit problems of information transmission and processing to be solved in a new way. A detailed rubrication on spintronics is given in order to discuss the possibility of publishing a separate edition of an abstract journal devoted to spintronics. 相似文献
898.
U. Casellato F. Fenzi P. Guerriero S. Sitran P. A. Vigato U. Russo M. Galgani M. Mendera A. Manasse 《Journal of Cultural Heritage》2003,4(4):337-353
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties. 相似文献
899.
900.
Beatrice S. Bartlett 《Archival Science》2007,7(4):369-390
This article describes the first half century of the Communist government’s supervision and management of the central-government
archives of the last two dynasties. Immediately with the Communist ascent to power in 1949, the new government took great
interest in assembling and protecting the country’s archival documents, readying the Ming-Qing archives for access to scholars,
and preparing for publication of selected materials. By the 1980s Beijing’s Number One Historical Archives, in charge of the
largest holding of Ming-Qing documents, had become the first Chinese authority to complete a full sorting and preliminary
catalogues for such a collection. Moreover, to facilitate searches, an attempt has recently begun to create a subject-heading
system for these and other holdings in the country. In the first half century’s final decades, foreign researchers were admitted
for the first time and tours and international exchanges began to take place.
相似文献
Beatrice S. BartlettEmail: |