The Influence of Hygroscopic Materials on the Fluctuation of Relative Humidity in Museums Located in Historical Buildings

ABSTRACT

The preservation of artefacts in museum collections is profoundly affected by fluctuations in temperature and, especially, relative humidity (RH). Since the late nineteenth century, many studies have been carried out on the best way to control hygrothermal conditions. In old buildings located in maritime temperate climate zones (such as Portugal) with strong thermal inertia, and which have low ventilation rate (relative to the volume and number of visitors), daily and seasonal hygroscopic inertia may help to assure the maintenance of RH stabilization conditions. The use of expensive active systems may be minimized through the passive behaviour of internal finishing building materials. This work presents the results of an experimental laboratory study conducted in a flow chamber to demonstrate the enormous potential of hygroscopic materials in stabilizing interior relative humidity. Based in these results and in-situ monitoring in a museum housed in a building, located in Porto, with a typical construction of the 1950s (granite masonry and reinforced concrete slabs), a numerical analysis was done to quantify the influence of hygroscopic materials in stabilizing the interior relative humidity.     

Proclaiming Library Worth in a Program Prioritization Process at a Mid-Sized Public University

Abstract

In an economic climate when colleges can no longer presume that legislators see institutions of higher learning as tacit public goods, institutions around the country are facing budget cuts. This article presents a case study of the experience of a mid-sized public state university and its Library in a budget crisis undergoing a university-wide program prioritization process. The authors review the process of writing three reports on the Library’s value, along with the approach to engaging staff in the process including a retreat. This article raises questions about what every library should consider assessing and provide tools for libraries navigating similar terrain.     

浅谈如何上好艺术体操选修课

对普通高校艺术体操选修课教学从形体姿态的培养、教学成套动作的编排,音乐的选择及口令、手势的运用等,进行了分析探讨.     

Measuring Search Engine Quality

The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures.     

论高校体育教学中学生创新思维能力的培养

通过树立现代体育教学观念、优化体育课堂教学、优选体育教学法等几个方面论述了学生创新思维能力的培养。     

浅析足球运动员意志品质及培养方法

阐述了足球运动中意志品质的作用和地位、培养足球运动员意志品质的意义及各种方法.     

中国男子足球队大赛期间阵容完整性的研究

采用录像观察法、数理统计法和文献资料法对中国队在亚洲杯期间主力阵容与98世界杯前3强主力阵容变化进行比较研究.结果表明:98世界杯前3强队伍主力阵容在比赛期间基本保持完整,而中国队主力阵容在最后一场比赛中极不完整.研究认为:影响中国队比赛阵容完整性的主要因素是战斗性减员和非战斗性减员.建议国家队应配备体能教练和心理学、运动医学、营养学专家;加强运动员的自我保护意识,使运动损伤最小化;合理运用技术动作减少红黄牌的发生.