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971.
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
972.
973.
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: |
974.
Mark G. Simkin William L. Kuechler 《Decision Sciences Journal of Innovative Education》2005,3(1):73-98
Instructors can use both “multiple‐choice” (MC) and “constructed response” (CR) questions (such as short answer, essay, or problem‐solving questions) to evaluate student understanding of course materials and principles. This article begins by discussing the advantages and concerns of using these alternate test formats and reviews the studies conducted to test the hypothesis (or perhaps better described as the hope) that MC tests, by themselves, perform an adequate job of evaluating student understanding of course materials. Despite research from educational psychology demonstrating the potential for MC tests to measure the same levels of student mastery as CR tests, recent studies in specific educational domains find imperfect relationships between these two performance measures. We suggest that a significant confound in prior experiments has been the treatment of MC questions as homogeneous entities when in fact MC questions may test widely varying levels of student understanding. The primary contribution of the article is a modified research model for CR/MC research based on knowledge‐level analyses of MC test banks and CR question sets from basic computer language programming. The analyses are based on an operationalization of Bloom's Taxonomy of Learning Goals for the domain, which is used to develop a skills‐focused taxonomy of MC questions. However, we propose that their analyses readily generalize to similar teaching domains of interest to decision sciences educators such as modeling and simulation programming. 相似文献
975.
ABSTRACT Full three-dimensional movements and external moments in golfers’ knees and the possible involvement in injuries have not been evaluated using motion capture at high sample frequencies. This study measured joint angles and external moments around the three anatomical axes in both knees of 10 professional golfers performing golf drives whilst standing on two force plates in a motion capture laboratory. Significant differences were found in the knee joint moments between the lead and trail limbs for the peak values and throughout all stages during the swing phase. A significantly higher net abduction moment impulse was seen in the trail limb compared with the lead limb (?0.518 vs. ?0.135 Nms.kg?1), indicating greater loading over the whole swing, which could contribute to knee lateral compartment or anterior cruciate ligament injuries. A significant correlation (r = ?0.85) between clubhead speed at ball contact and maximum joint moment was found, with the largest correlations being found for joint moments at the top of the backswing event and at the end of the follow-through. Therefore, although knee moments can contribute to high clubhead speeds, the large moments and impulses suggest that they may also contribute to chronic knee injuries or exacerbate existing conditions. 相似文献
976.
Samuel W. Oxford Rob S. James Michael J. Price Carl J. Payton Michael J. Duncan 《Journal of sports sciences》2017,35(16):1658-1665
The purpose of this study was to compare arm–leg coordination and kinematics during 100 m breaststroke in 26 (8 female; 18 male) specialist breaststroke swimmers. Laps were recorded using three 50-Hz underwater cameras. Heart rate and blood lactate were measured pre- and post-swim. Arm–leg coordination was defined using coordination phases describing continuity between recovery and propulsive phases of upper and lower limbs: coordination phase 1 (time between end of leg kick and start of the arm pull phases); and coordination phase 2 (time between end of arm pull and start of leg kick phases). Duration of stroke phases, coordination phases, swim velocity, stroke length (SL), stroke rate (SR) and stroke index (SI) were analysed during the last three strokes of each lap that were unaffected by turning or finishing. Significant changes in velocity, SI and SL (P < 0.05) were found between laps. Both sexes showed significant increase (P < 0.05) in heart rate and blood lactate pre- to post-swim. Males had significantly (P < 0.01) faster swim velocities resulting from longer SLs (P = 0.016) with no difference in SR (P = 0.064). Sex differences in kinematic parameters can be explained by anthropometric differences providing males with increased propelling efficiency. 相似文献
977.
Natalie C. Simpson Philip G. Hancock 《Decision Sciences Journal of Innovative Education》2011,9(2):235-253
This article chronicles the coordination and better integration of existing institutional resources to support cocurricular themes embedded in the provision of a large enrollment, video‐mediated undergraduate operations management (OM) course. The name Project Cheddarfield refers to a 2008 initiative in which two professors team‐taught an OM course to over 600 undergraduates on two different continents through the repeated rapid exchange of digital video between the United States and Singapore. Simultaneously infused in this core curricular delivery were themes of global awareness and study‐abroad, including the promotion of one particular opportunity that bridged the two campuses. This action research narrative spans over 5 years of related activity leading up to the initiative, as this project is best understood as a trajectory, or the evolving result of design adapting to unfolding realities. 相似文献
978.
Brenda I. Rowe Wesley S. McCann Craig Hemmens 《Journal of Criminal Justice Education》2013,24(4):551-576
This study assesses the authorship of legal scholarship within 20 criminology and criminal justice (CCJ) journals from 2005 to 2015, examining trends over time and variation across journals in the prevalence of sole-authorship and the mean number of authors and identifying the most prolific authors of legal scholarship published in CCJ journals. The study thus sheds light on the extent of collaboration among CCJ legal scholars and identifies CCJ legal scholars who have remained largely invisible due to their focus on a marginalized subfield. 相似文献
979.
Many scientists and coaches are interested in mechanical power produced during cycling, and use Schoberer Rad Me\technik (SRM)
bicycle power cranks to obtain this data. However, it has been expensive and difficult to calibrate SRM cranks, causing much
of the collected data to be unreliable. We present a static method, derived from first principles, for obtaining a calibration
factor for SRM cranks.
A known mass and lever arm (chainring of a known diameter) are used to apply a known torque load to the instrument in four
positions, and the output frequencies are used to calculate the calibration factor in Hz/Nm. The reproducibility of this method
is ±0.01 Hz/Nm, which is acceptable for the application of the instrument, which is measurement of mechanical power application
by cyclists at the crank.
The method is reliable, inexpensive, and easy to set up, and will allow higher confidence in data collected using SRM power
cranks. We recommend calibration of the power meter once every six months because of the measured drift of the calibration
factor over time. 相似文献
980.
Ethel S. Heebink 《Clearing house (Menasha, Wis.)》2013,86(8):504-506