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21.
The last step of the Information Retrieval process is to display the found documents to the user. However, some difficulties might occur at that point. English texts are usually written in the ASCII standard. Unlike the English language, many languages have different character sets, and do not have one standard. This plurality of standards causes problems, especially in a web environment, where one may download a document with an unknown standard. This paper suggests a purely automatic way of finding the standard which was used by the document writer based on the statistical letters distribution in the language. We developed a vector-space-based method that creates frequencies vectors for each letter of the language and then matches a new document's vectors to the pre-computed templates. The algorithm was applied on various types of corpora in Hebrew, Russian and English, and provides an efficient solution to the stated problem in most cases.  相似文献   
22.
文化可分为自在的文化与自为的文化。教师的教学生活可分为日常教学生活与非日常教学生活。自在的文化与日常教学生活具有内在一致性。日常教学生活这种自在的文化表征通过教师思想意识上的保守性、日常教学活动的重复性以及教师处理日常教学事务的经验性而表现得淋漓尽致。要对教师的日常教学生活进行文化改造,必须变革日常教学生活的文化根基,在自在文化与自为文化之间保持张力,构建教师学习协同体,促进教师的教学文化自觉。  相似文献   
23.
This article presents the intervention process carried out on a work of art created by artist Yolanda Gutiérrez Acosta, using a series of ephemeral materials such as butterfly wings and agave thorns. The work, an installation from 2002, is entitled ‘Efímeras’ (‘Ephemera’) and consists of 12 flowers mounted on acetate sheets and attached to the same with vinyl acetate copolymers and acrylic acid esters (Mowilith®). These flowers are installed on the floor in a bed of dried flowers. The conservation of contemporary art can lead to some previously unimaginable problems for restorers. Current works of art are somewhat material in nature, but they also have a conceptual dimension that is essential for their artistic interpretation. The artist’s participation in the decision-making process prior to the restoration was quite useful. The passage of time, its effect on the work, and the need to understand the possibility of the demise and destruction of the work were implicit as of the onset of its creation, such that, according to the artist, we are forced to reflect upon the possibilities of its future state.  相似文献   
24.
[目的/意义] 从用户角度出发,研究基于用户自然标注的TF-IDF辅助标引算法。[方法/过程] 首先以核心期刊论文中作者标注的关键词和分类号为源数据,通过对关键词词频进行统计,使用TF-IDF算法构建用户标注词表、形成标引知识库,然后通过IK Analyzer分词软件对待标引的科技项目数据进行切词和停用词处理,进而使用TF-IDF算法和位置加权算法提取科技项目数据的特征词,最终实现对科技项目数据进行关键词和分类的同步标引。[结果/结论] 实验结果表明,机标关键词与人标关键词的相似比在60%以上的科技项目数据占总数的68.1%,机标分类号与人标分类号前三位一致的占总数的83.9%,结果表明基于用户自然标注数据并采用TF-IDF算法在关键词和分类标引方面是可行的。  相似文献   
25.
ABSTRACT

Working on preventive conservation in Italy is difficult but not impossible. After small successes and setbacks convincing museums to adopt elements of preventive conservation in the 1990s, the first author (Rossi Doria) was contracted for 15 years to preserve the historic carriages and associated objects of the Presidency of the Republic of Italy. This required patience to overcome or circumvent obstacles such as an inflexible bureaucracy and the absence of any formal recognition of preventive conservation within the educational and contractual systems for heritage conservation. The key factors in his success were the support of the curators, the financial and planning autonomy of the Presidency, and the obvious need for conservation and preservation of these elegant and complex objects. The program began in 2001 with the recovery of the forgotten collection from inappropriate storage in several locations. The entire collection was surveyed and recorded, not only the carriages but also thousands of harnesses, saddles, clothing, fabrics, weapons and memorabilia. Multiple preventive and interventive actions were undertaken, such as pest eradication for all sensitive materials, environmental surveys, and everyday maintenance, as well as complex treatments for the ornate carriages. Analysis by country of published articles on preventive conservation and of IIC membership both confirm that the topic is not as well established in Italy as in many other countries. Some reasons and solutions are proposed.  相似文献   
26.
ABSTRACT

This study aimed to assess the effect of playing surface (Natural [NT] and Artificial [AT] Turf) on the fatigue response to a soccer-specific exercise protocol (SSEP). Eighteen male soccer players completed the SSEP on NT and AT with pre-, post-, and 48 h post-assessments of eccentric knee flexor (eccKF) and concentric knee extensor peak torque (PT), peak countermovement (CMJ) and squat jump (SJ) height, and Nordic hamstring break angle. No significant main effects for surface or any surface and time interactions were observed for any of the outcome measures, except for eccKF PT recorded at 3.14 rad·s-1, which was significantly lower 48 h post-trial in the AT condition (AT = 146.3 ± 20.4 Nm; NT = 158.8 ± 24.7 Nm). Main effects for time were observed between pre- and post-trial measures for eccKF PT at all angular velocities, Nordic break angle, CMJ and SJ height. Nordic break angle, and both CMJ and SJ height were significantly impaired 48 h post-trial when compared to pre-trial. The findings of the current study suggest surface dependent changes in eccKF PT which may have implications for recovery and subsequent performance after competition on AT.  相似文献   
27.
濮人曾经是古哀牢王国的主体民族之一,在云南境内有广泛的分布,但由于政治和战争的原因,以及汉民族的迁入,哀牢濮人经历了漫长的迁徙,分化为多个少数民族。但哀牢濮人们在生产和生活实践中自发形成的朴素的生态适应性并没有因民族衍变而消失,而是超越环境的变迁顽强地传承下来,成为我们今天调适人与自然环境,处理人地关系的很好借鉴。  相似文献   
28.
通过振动试验,得到了简支矩形等截面梁的挠度和频率随荷载变化的曲线,结果与破损模态静力试验结果一致。  相似文献   
29.
在对德国古典哲学的批判研究中,通过对历史概念的重新阐释,借助于“总体性”范畴,卢卡奇从恩格斯的自然辩证法走向总体性历史辩证法。他的早期历史辩证法思想对马克思主义哲学“历史”重建有重要的贡献,同时也具有一定的历史局限性。  相似文献   
30.
“自然无为”是老子哲学思想的显著特色。老子思想中“自然无为”命题并不是无所作为,随心所欲,而是要以辩证法的原则指导人们的社会生活,帮助人们寻找顺应自然、遵循事物客观发展的规律。结合道法自然的生态理念、清静无为的处世哲学、自然纯真的人生旨趣等若干问题,揭示老子“自然无为”这一思想的现代价值。  相似文献   
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