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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 Alfred Taubman Medical Library at the University of Michigan has offered instruction in online literature searching to third-year pharmacy students as a component of the course "Drug Information and Scientific Literature Evaluation" since 1983. In the spring of 1989, a follow-up study was conducted to assess the impact of instruction on four classes of graduates. Of a pool of 151 graduates, 90 (60%) responded to a mailed questionnaire on their use of information and computerized literature searching. The respondents were divided into four subgroups: end-user searchers, users of intermediaries, end users who used intermediaries, and those who did not use computerized literature search systems. Seventy-two percent of the respondents used some type of computerized literature searching, and 42% performed their own searches. The four subgroups differed in general computer use, familiarity with MEDLINE search terminology, information use, reasons for using or not using literature searching, and characteristics of searches (i.e., type, time frame, amount, and frequency). Training in end-user search systems appears to have had an impact on the continued use of computerized literature searching several years after the formal educational program.  相似文献   
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Physician information seeking: improving relevance through research   总被引:1,自引:0,他引:1  
Health sciences libraries have considerable potential as resources for both formal continuing professional education, as well as the informal continuing education that results from the professional's efforts to solve problems in daily practice. While there is a growing interest in making the resources of health sciences libraries more accessible to practitioners on a routine, day-to-day basis, there also needs to be more awareness of how, when, where, and why professionals look for information in the context of practical problems. This paper reviews recent research that identifies the context in which physicians seek information and advice from external sources, the information sources that physicians access, and the factors that influence which particular sources are sought. The results indicate that physicians vary in their information needs, preferences, motivations, and strategies for seeking information. This diversity suggests that health sciences libraries, in their efforts to be more accessible, should consider "market research" to determine the needs, preferences, and use patterns of the library's targeted users. Libraries may also benefit from exploring alternative methods of improving access to their resources.  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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