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11.
利用正则表达式在字符串操作上的优势,实现从不规则含噪页面中对油价事件信息的抓取,指出实现中的难点要点,并验证正则表达式在字符串处理中强大的结构描述能力。  相似文献   
12.
1901年1月29日,因八国联军入侵而尚在西安的清廷发布变法上谕:"世有万古不变之常经,无一成不变之成法。穷变通久,见于《大易》;损益可知,著于《论语》。盖不易者三纲五常,昭然如日月之照世;而可变者令甲令乙,不妨如琴瑟之改弦。伊古以来,代有兴革。  相似文献   
13.
《文物保护研究》2013,58(1):20-3
Abstract

Severe corrosion was found covering the brass beads on several beaded belts. The corrosion was a mixture of copper soaps and zinc soaps, and was so thick in some places that it completely buried the brass beads. One of these belts was chosen as a test case for cleaning. The details of the cleaning are described, as are the effects of the corrosion process on the beads and surrounding organic materials. Two supporting studies are also reported: tests of the solubility of the corrosion in a variety of organic solvents, including mixtures of ethanol and petroleum-based solvents; and tests of leather dressings and other coatings on brass, copper, and zinc coupons in various relative humidities (RH), to determine what values of RH could be recommended for storage.  相似文献   
14.
Eliminating noisy information and extracting informative content have become important issues for web mining, search and accessibility. This extraction process can employ automatic techniques and hand-crafted rules. Automatic extraction techniques focus on various machine learning methods, but implementing these techniques increases time complexity of the extraction process. Conversely, extraction through hand-crafted rules is an efficient technique that uses string manipulation functions, but preparing these rules is difficult and cumbersome for users. In this paper, we present a hybrid approach that contains two steps that can invoke each other. The first step discovers informative content using Decision Tree Learning as an appropriate machine learning method and creates rules from the results of this learning method. The second step extracts informative content using rules obtained from the first step. However, if the second step does not return an extraction result, the first step gets invoked. In our experiments, the first step achieves high accuracy with 95.76% in extraction of the informative content. Moreover, 71.92% of the rules can be used in the extraction process, and it is approximately 240 times faster than the first step.  相似文献   
15.
The webbing clothes moth Tineola bisselliella (Hummel, 1823) is one of the most common museum pests and can be found all over the world. The larvae damages objects made of feather, wool, fur, and other keratinaceous materials. Pheromone traps are important tools in integrated pest management, which allow the detection of infestations and evaluation of their extent. Organic-rich dust (detritus) or other materials of animal origin, such as dead birds, can be an alternative food source for the moths. This paper analyzes monitoring data collected with pheromone traps from six different museums in Vienna and Berlin and tries to differentiate between moths resulting from infested objects or moths coming from other food sources, such as organic-rich dust. Annual totals of moths trapped and catch rate (moths per trap) are important guides for selecting appropriate remedial measures. Long-term data (over six years) enabled us to interpret monitoring results and differentiate between active infestation of objects and cleaning or housekeeping problems. However, detailed knowledge of the site and buildings, availability of high-quality food for the larvae, and lack of regular cleaning are also important factors to consider when interpreting the data.  相似文献   
16.
The paper presents strategies for the conservation of historical textiles in Egypt that have been in uncontrolled storage and display. The silk textile is highly decorated, multicoloured and dates to the Ottoman period, and was exhibited in case # 12014. The textile has various types of deterioration. An examination and analysis of the textile was undertaken in order to develop a plan of conservation treatment. FTIR was used to identify the kinds of dyes and organic stains, and XR-D was used to identify mordants and dust. Light microscope and SEM were used to identify the kind of fibers, their condition and surface morphology. The effects of cleaning materials on the natural dyes were tested. The researcher designed a new metallic frame support system which has advantages over the wooden frames commonly used in Egypt. This presentation will review the conservation treatment step by step. Poultices were used to remove all the sticking cardboard and adhesive. Old conservation repairs were removed. Separated parts were supported. Cleaning included mechanical and wet cleaning. New silk fabrics dyed with natural dyes were used to complete the missing parts. The textile was supported on new linen fabric which was stretched on a metal frame. The method of exhibition will be discussed. Photographs are included to document the conservation process.  相似文献   
17.
徐斌  祝秀琴 《科技广场》2012,(7):161-163
旧油桶重新投入使用前,必须对油桶进行清洗及干燥。本文通过对清洗原理及待洗油桶内部油垢状况的研究,提出了一种油桶的清洗工艺流程。  相似文献   
18.
润滑及清洁度对滚动轴承寿命的影响程度   总被引:1,自引:0,他引:1  
本通过应用滚动轴承新的寿命计算方法对不同工作条件(润滑和清洁度)下轴承寿命的对比计算,来论述润滑与清洁度对轴承寿命影响的程度,证明合理润滑与密封设计的重要性。  相似文献   
19.
INTRODUCTION Waterjet cleaning technology is mainly achieved by an erosion process of high pressure water to re-move coating materials.Louis and Schikorr(1982)identified deposits removed by high-speed waterjet cleaning as rust,oil,rubber,organics,etc.,and inves-tigated the relationship between the properties of the deposits and substrata.Summers(1982)investigated the correlation between the standoff distance,pres-sure and cleaning effectiveness.Saunders and Barton(1986)investigated the r…  相似文献   
20.
The scientific approach to the restoration and monitoring of mural paintings, at S. Girolamo Chapel – SS. Annunziata Church in Florence, is reported as a fruitful example of the synergic collaboration between restorers and scientists in the planning and development of conservative interventions. Before restoration, the painting technique and the state of preservation of the pictorial cycle have been investigated firstly by close examination of the painted surfaces and then by optical and/or SEM-EDS microscopy and μFT-IR spectroscopy on appropriately selected samples. In particular, the original constituent materials and those belonging to subsequent restorations were characterized together with those originating from decay processes. In this mural painting cycle, a peculiar “fresco” technique has been used although an auxiliary binder for pigment distemper has been also employed. The use of this technique, sometimes in an improper way together with uncorrected restoration interventions, are the main responsible of the unsatisfactory state of conservation of many painted areas. Preliminary conservation trials and scientific studies were carried out to design the most convenient restoration intervention and to verify the correctness and non-invasive of the necessary operations. Special attention was devoted to cleaning procedures, continuously monitored by a physico-chemical methodology, mainly based on microinvasive, microscopic and spectroscopic investigations, to evaluate the efficiency, advantages and drawbacks of the proposed cleaning procedures and define the most appropriate ones. Finally, specific decay markers have been recognized, by a comparison of the results obtained from the detached samples with those deriving from artificially aged models, to be used for a correct future monitoring and maintenance of the wall paintings.  相似文献   
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