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Research in Higher Education - Increasingly, undergraduates take more than 4 years to complete a baccalaureate, a situation widely perceived as a waste of time and money, for students,...  相似文献   
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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   
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In the IR field it is clear that the value of a system depends on the cost and benefit profiles of its users. It would seem obvious that different users would prefer different systems. In the TREC-9 filtering track, systems are evaluated by a utility measure specifying a given cost and benefit. However, in the study of decision systems it is known that, in some cases, one system may be unconditionally better than another. In this paper we employ a decision theoretic approach to find conditions under which an Information Filtering (IF) system is unconditionally superior to another for all users regardless of their cost and benefit profiles.It is well known that if two IF systems have equal precision the system with better recall will be preferred by all users. Similarly, with equal recall, better precision is universally preferred. We confirm these known results and discover an unexpected dominance relation in which a system with lower recall will be universally preferred provided its precision is sufficiently higher.  相似文献   
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The economic success of some of the countries within the East Asian region has generated a range of studies which have attempted to identify the sources of that growth. One strand within these analyses has focused on the critical role of schooling in the accumulation of human capital. This paper examines the role which education has played in the rapid development of the four 'Asian Tigers'; namely: Hong Kong, Taiwan, South Korea and Singapore. It is argued that whilst patterns of educational provision displayed some common features there were also significant differences in other areas such as the role of the state, sources of educational funding, the role of technical education and of the school curriculum.  相似文献   
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Our argument in this paper is that the model of literary progression which Bakhtin (1981, 1986) expounds in his writing on the chronotope can generate insight into the processes through which pupils improve their writing. We suggest more generally that there are concepts and clues in Bakhtin's historical model of the development of the European novel and in his theory of dialogue which can be helpful in both the evaluation and teaching of classroom writing.  相似文献   
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The aim of this study was to investigate the effects of extensive endurance training (15-25 h per week) on the development of maximal oxygen uptake (VO2 max) in boys from puberty. Maximal oxygen uptake was measured a number of times each year from the age of puberty and for the next 6-9 years in seven young male elite cross-country skiers. Mean VO2 max was measured as 76.3 and 80.1 ml kg-1 min-1 at the ages of 14 and 15 years respectively. Despite the fast rate of growth during puberty, maximal aerobic power showed seasonal variations from the age of 14, reaching a plateau at the age of 15, whereas VO2 max (ml kg-2/3 min-1) increased continuously. It is concluded that, during puberty, boys probably attain significant increases in VO2 max when appropriate amounts of endurance training are undertaken.  相似文献   
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