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John Ashworth 《Higher Education Quarterly》1997,51(2):164-188
Since 1990, there has been considerable debate concerning the benefits of the expansion of higher education and the appropriate way to fund such an expansion. This paper demonstrates that three factors are decisive to the individual contemplating higher education: national economic growth; the relative earnings of graduates and non-graduates; the difference between the average and the marginal student. The results, of analysis based on rates of return, reaffirm the view that a proportion of the costs involved in higher education can be transferred to the graduates themselves in the form of loans. However, there appear to be limits to the costs that can be transferred if all students are to judge that undergraduate study is a worthwhile proposition. Notwithstanding this, most students could be lent more income to study than is now the case and indeed an average student would be advised to take any loans despite the greater debt. Marginal students, however, are making a risky private investment and, therefore, any decisions to further expand may result in students not taking up the places. 相似文献
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An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay. 相似文献