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1.
《文物保护研究》2013,58(4):190-192
AbstractThree methods of consolidating stone have been compared using Maastricht limestone as the substrate. They are: impregnation with polymer (Paraloid B 72) from solution; impregnation with a mixture of monomers followed by (a) γ-ray polymerization or (b) free-radical initiated thermal polymerization. The best results were obtained with the third method. 相似文献
2.
《文物保护研究》2013,58(3):111-125
AbstractThe problem of conservation of sound waterlogged oak and in particular the limitations of polyethylene glycol impregnation are briefly considered. Development of a new process involving dehydration with acetone and impregnation with rosin is described. Results pertaining to the experimental evaluation of the procedure are presented and suggest good success in its use. Applications of the process in the conservation of soft- and heavily waterlogged woods are described. 相似文献
3.
《文物保护研究》2013,58(3):180-197
AbstractCorrosion rates are presented for metals in the aqueous solutions intended for treating both the wood and the metal components of a waterlogged wood-metal composite object. The metals include lead, mild steel, cast iron and the copper alloys of bronze, cast brass and wrought brass. The corrosion rates were determined using a standard weight-loss method in which clean metal surfaces were immersed in the solutions for two months at room temperature. The treatment solutions included Acrysol® G-11O for lead, Witcamine® RAD 1100 for copper alloys and Pluracol® 824 or the corrosion inhibitor Hostacor® KS 1 in PEG 400 for iron. These treatment solutions were prepared in distilled water as well as in a synthetic seawater. For reference, metal corrosion rates were also determined in distilled water, synthetic seawater and PEG 400. The results demonstrate that, in general, clean metal surfaces corrode more slowly in the treatment solutions than in PEG 400 solutions. However, before recommending these solutions for the treatment of composite objects, further testing is needed to determine how effective they are in reducing the corrosion rates of metals covered with a thick corrosion crust, and to see if Acrysol G-110 is capable of bulking and consolidating waterlogged wood. 相似文献
4.
《文物保护研究》2013,58(2):134-153
AbstractA broad outline of the considerations which arise with regard to the conservation of a museum collection of tapestries is given in this paper. The various types of damage to, and deterioration of, tapestries is discussed.Various methods of washing and dry cleaning, and the equipment necessary for these procedures, are reviewed, and a caution is included as to the necessity of testing all dyes for colour fastness in both water and any solvent used for dry cleaning. The equipment, materials and techniques of repair are discussed; three methods of repair being currently used in museums and specialist workshops — re-weaving, stitching on to a backing and the use of synthetic resins for impregnation and adhesion to a woven support. It is suggested in conclusion that the optimum method of repair in museums is stitching on to a backing. More research must be undertaken into the use of synthetic resins, and re-weaving usually alters the original appearance of the tapestry.Finally, the need for specialised conservation staff in a museum with a tapestry collection is emphasised. 相似文献
5.
ABSTRACTThis study explores how two nonprofit media organizations–PublicSource and Philadelphia Community Access Media (PhillyCAM)–have transformed their legacy practices to better connect within and serve marginalized populations in Pittsburgh and Philadelphia, PA. As traditional newsrooms have been depleted by dire financial realities, new journalism outcroppings have heeded the Knight Commission’s Informing Communities: Sustaining Democracy in the Digital Age (2009) report and, consequently, revised their approaches to community engagement. Adjacent to these reformed legacy newsrooms are community media organizations that operate a municipality’s public, educational, or government (PEG) access media production facilities. Although PEG access media’s legacy has no clear genealogical ties with traditional journalism, an increasing amount of PEG operations over the past ten years have started to intentionally test editorialized forms of community news reporting. The data collected and assessed in this study has indicated that news organizations like PublicSource have an explicit need to do more relational community engagement work that will enable it to fill hyperlocal information gaps and better serve marginalized populations. Community media organizations like PhillyCAM have extensive experience engaging diverse publics; however, as this study reveals, they could benefit from employing formalized news production methods that are guided by journalistic standards. 相似文献
6.
《文物保护研究》2013,58(3):110-157
AbstractConsolidation of decayed wooden artifacts can be achieved by impregnation with epoxy prepolymer dissolved in a mixture of toluene and glycidyl ether and subsequent polymerization in situ. The principles of selecting the successful method of application are discussed, and the details of the procedure given. Impregnation with the described solution causes insignificant expansion of the wood in contrast to the action of polyvinyl acetate in alcohol solution. 相似文献
7.
AbstractPolyethylene glycols (PEG) can be detected in wood by their in situ formation of coloured complex compounds. Solutions of potassium bismuth iodide/barium chloride and of bromine/potassium iodide are suitable for sprayingdirectly onto wood, and may even be used on dark-coloured wood by mixing chalk powder into the reagent. By adopting a print-off technique onto damp filter paper, the distribution of PEG in wood can be demonstrated even more exactly, even from very small samples. Print-offs are developed into differentiated coloured pictures withsolutions of potassium bismuth iodide/barium chloride, iodine/potassium iodide or ammonium cobalt (II) thiocyanate. 相似文献
8.
Wendy Jo Girven 《图书馆管理杂志》2013,53(8):1007-1017
ABSTRACTSpecial academic libraries are in the unique position to blend the innovative and user focused services of academic libraries with the niche collections of special libraries when serving their Millennial student population. Millennials are a highly researched generation, but special libraries may have not updated their services to reflect the needs and expectations of this rising generation. Maine Maritime Academy's Nutting Memorial Library serves as a case study of methods in which special academic libraries can incorporate Millennials' expectations of library spaces, services, and collections in sustainable ways. 相似文献
9.
SUMMARY Describing her experience of establishing an Electronic Document Delivery Service at the library of the Lahore University of Management Sciences (LUMS), the author discusses the various issues, which significantly effect the net cost, delivery time and management process of providing such a service by a library in Pakistan. While presenting multiple options leading to an effective solution, the advantages and disadvantages of each option have been highlighted, and their implications, with particular reference to Pakistani libraries, have been discussed. The various points to be considered by Pakistani Librarians, while selecting a commercial Document Provider, have also been discussed. In the end, the author discusses the potential of using the Electronic Document Delivery facility as a time-saving and cost-effective tool for Resource Sharing among libraries in Pakistan. 相似文献
10.
11.
《文物保护研究》2013,58(1):51-62
AbstractThe conservation of non-metallic seals is an aspect of archival conservation which is all too often neglected.The authors show the most usual causes and forms of damage together with various methods of treatment. Among the aspects discussed are composition and manufacture; cleaning and repair of single and double-faced seals made of beeswax, shellac and other thermoplastic compounds; the conservation and repair of papered seals, together with seals and wafers applied en placard to documents; and methods of packing and storage used in the University of Glasgow Archives. 相似文献
12.
Natural polymers as alternative consolidants for the preservation of waterlogged archaeological wood
In recent years, there has been increased interest in examining alternative polymers for the conservation of archaeological artefacts, particularly waterlogged timbers, providing better, renewable, greener alternatives to poly(ethylene glycol) (PEG). The degradation of PEG consolidants in the timbers of the sixteenth century warship Mary Rose has been examined and the rheological and thermal properties of PEG have been compared with its monomethyl and dimethyl ethers and several polysaccharide consolidants (chitosan, guar, and 2-hydroxyethyl cellulose) in order to evaluate their potential as alternative consolidants for the conservation of waterlogged wooden artefacts. Additionally, the effect of the polymers on the archaeological wood was characterised by thermogravimetric analysis and solid-state nuclear magnetic resonance spectroscopy. The results suggest that the future of conservation technologies lies with polysaccharide consolidant materials, which show enhanced compatibility with wooden artefacts with no detectable side effects while also being cheap, with extremely low toxicity, renewable, and sustainably resourced. 相似文献
13.
《Communication Teacher》2013,27(3):166-174
Courses: Communication Research Methods, Senior Capstone. Objectives: After completing this course, students will be able to: ? appreciate the role of empirical communication research in solving social and organizational problems; ? identify issues and needs in the community that can be addressed with empirical communication research; ? choose appropriate research methods for addressing different issues and needs; ? use various communication research methods to address community issues and needs; ? present research findings and recommendations to community organizations; ? demonstrate an increased commitment to active citizenship. 相似文献
14.
Oren Kurland 《Information Retrieval》2009,12(4):437-460
To obtain high precision at top ranks by a search performed in response to a query, researchers have proposed a cluster-based
re-ranking paradigm: clustering an initial list of documents that are the most highly ranked by some initial search, and using
information induced from these (often called) query-specific clusters for re-ranking the list. However, results concerning the effectiveness of various automatic cluster-based re-ranking methods have been inconclusive. We show that using query-specific clusters for automatic re-ranking
of top-retrieved documents is effective with several methods in which clusters play different roles, among which is the smoothing of document language models. We do so by adapting previously-proposed cluster-based retrieval approaches, which are based on (static) query-independent
clusters for ranking all documents in a corpus, to the re-ranking setting wherein clusters are query-specific. The best performing
method that we develop outperforms both the initial document-based ranking and some previously proposed cluster-based re-ranking
approaches; furthermore, this algorithm consistently outperforms a state-of-the-art pseudo-feedback-based approach. In further
exploration we study the performance of cluster-based smoothing methods for re-ranking with various (soft and hard) clustering
algorithms, and demonstrate the importance of clusters in providing context from the initial list through a comparison to
using single documents to this end.
相似文献
| Oren KurlandEmail: |
15.
Mary Ronnie 《International Information and Library Review》2013,45(4):359-361
AbstractThe Australian public sector, like that in many other countries, has been undergoing substantial reform for more than a decade. The changes, which have been introduced as ways of improving efficiency, effectiveness and accountability, have affected all areas of government operations. The methods for achieving the improvements have involved substantial change in respect of financial management, goal setting and evaluation, structural change and human resource management policies. Occurring concurrently with change within the public sector, the Australian Commonwealth and various state governments have been pursuing substantial change programs in other areas, such as industrial relations, which have had many similar aims to those of the government reform programs, a major one being the improvement of efficiency and effectiveness in the workplace. Libraries have felt, and will continue to feel, the impacts of these reforms as new management requirements and methods are introduced. This paper briefly describes a number of aspects of the various reform programs highlighting their impacts to date and some of their likely future impacts on the librarian and the library workplace. 相似文献
16.
《文物保护研究》2013,58(4):316-326
AbstractA survey is given of polychromed sculpture in Sweden. Historical aspects of the care of sculptures are discussed. Many retables have been imported from Lübeck and Antwerp. Polychromed sculptures are often well preserved because there was hardly any iconoclasm in Sweden. Many need treatment however due to various forms of neglect. A special case—the triptych of Kärrbo (c. 1500)—is described in detail from a technical point of view. 相似文献
17.
《Behavioral & Social Sciences Librarian》2013,32(2):39-57
The First Edication of The Thesaurus of Psychological Index Terms was published in 1974 by the American Psycholigical Association to answer the need for controlled vocabulary to represent precissely the literature of psychology and related disciplines contained in Psychological Abstracts and the PsychINFO database. As the field of psychology has grown and evolved, five subsequent editions of the Thesaurus have improved and extended the original vocabulary of 4000 postable and nonpostable terms. In addition, several featues have been added, including a rotated alphabetical terms section, scope notes, posting notes, and, in the new Sixth Edition (1991), an index term clusters option. In maintaining the Thesaurus, PsychINFO's indexing staff seeks to reflect the ever-changing field of psychology and the literature that describes it. 相似文献
18.
Richard J. Cox 《International Information and Library Review》2013,45(3):195-231
AbstractThere has been little systematic research about the image of archivists and archives. This study considers how this topic has been handled in an eight month span of The New York Times from late 1992 to mid 1993. While the news media’s coverage is present, it is clear that archives are treated as curiosities or when they relate to political disputes, are associated with prominent figures, or have interesting or different views to offer on important topics. 相似文献
19.
《文物保护研究》2013,58(4):157-167
AbstractThe winter climatic conditions of much of Canada provide an ideal environment for freeze-drying. We have been attempting to use these conditions for the drying of large waterlogged timbers. In the freeze-drying process the wood is kept in a frozen state and the drying proceeds by sublimation. We are particularly concerned with the treatment of large timber which present great difficulties when treated by the accepted methods. A structure was built to keep snow and rain off the wood but which allowed air to pass over it. The structure was covered with polyethylene sheet to allow the sun to shine on the wood surface and heat it. Weight changes in the wood were measured with a load transducer and temperature wa followed with thermocouple probes. Temperature and relative humidity of the surrounding air were recorded instrumentally. The timbers were of several varieties of wood in various states of decomposition. All of the wood dried quickly and much of the water was removed. This technique appears to have the potential to treat large quantities of timber in an economic and simple way. 相似文献
20.
《文物保护研究》2013,58(3):97-102
AbstractPrehistoric decorated caves, witness to man's artistic activity many thousands of years ago, have survived till now thanks to favourable conditions of conservation. Since their discovery, as a consequence of changes brought about by various developments and heavy visitor traffic, their precarious equilibrium has been threatened. Before we attempt to strengthen or to restore this state of equilibrium, it is desirable to understand the mechanisms governing the current in situ conditions in relation to the circulation of air, variations of humidity and temperature, the relationship between the cave and its surroundings, and the role of microorganisms. 相似文献