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Working Graphs     
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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   
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The current societal and professional context presents a variety of ethical challenges to decision makers. The importance of educational preparation for ethical decision-making and ethical leadership has been addressed in the literature of library and information science (LIS), among other professions. However, it can be quite difficult to measure the impact of professional ethics education on students. This article is based on an evaluation of published original research related to ethics education in disciplines supported by professional education, including education, nursing, allied health, journalism, social work, public health, engineering, and LIS. The study considers data related to research design, methodologies used, populations studied, approaches to measuring impact, levels of impact, and publication in the journal literature. Results indicate more extensive research in education and nursing as compared with other fields, a lack of baseline data gathering for comparison, a reliance on a limited number of data-gathering techniques, and a tendency toward studying alumni over current students  相似文献   
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彻底简化IT     
如何实现"简化IT"的战略,这是困扰很多企业,尤其是CIO的一个重要问题。本文以日本新生银行的例子来诠释如何彻底简化IT。中世纪哲人William of Ock- ham说过,理论应该尽可能的简单。同样的原则适用于企业IT系统:它们按照尽可能少的标准  相似文献   
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