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1.
《Journal of Map & Geography Libraries》2013,9(1):37-66
Abstract Users of geographic data may not be able to afford to purchase and implement a dataset that does not finally meet their needs. Therefore, metadata has a very important role in the information supply environment of geographic data. The development of national/local spatial data infrastructures recognizes the importance of metadata, as do the digital libraries providing spatial data. The new ISO 19115:2003 standard of metadata for geographic information is introduced briefly. In particular, geographic information can be made available as digital maps (or images) that are meant for visual use, or as datasets meant for computational use. Metadata for digital maps is closely related to the metadata elements for conventional maps and can be enhanced by providing a sample map with the data. The case of computational use of geographic data is more complex. There are several details that may appear crucial when determining the fitness of data for an intended use. Understanding the importance of the crucial factors in each use case requires professional skills from the users of metadata. 相似文献
2.
《文物保护研究》2013,58(2):112-115
AbstractThe present work demonstrates by means of two practical examples the extreme importance of examination of cross sections of metal threads to obtain an overview of their structure and of the different materials employed in their manufacture. Problems that might be caused by disturbance of surface features during polishing were prevented by covering the sample before embedding with a layer of nickel, using electroless deposition. Results from scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX) showed that, although the mean chemical composition of both metal wires is the same, their metallurgical structure is completely different: one consisting of pure silver with inclusions of copper particles and the other a silver–copper alloy. 相似文献
3.
《文物保护研究》2013,58(3):199-210
AbstractDescente des vaches (1836) by Théodore Rousseau in the Mesdag Collection in The Hague is barely readable and its paint layers are in poor condition. The surface of the painting is strongly deformed and cracked, the whole painting has darkened and especially the greens have lost all or most of their colour resulting in brown passages. Large passages of the painting that were painted with multiple thick and medium-rich layers have darkened dramatically. This paper proposes that the degradation of Emerald green (Cu(C2H3O2)2·3Cu(AsO2)2, copperacetoarsenite) – the main green pigment used in this painting – is a significant factor in the cause of the darkening. Electron backscatter images reveal that the Emerald green particles are shown different degrees of degradation: from partially to completely disintegrated. Elemental maps show that arsenic is distributed throughout the paint cross section, with relatively higher concentrations around iron- and aluminium-containing particles, and in the varnish layer. Imaging-Fourier-transform infrared microscopy detects copper soaps in the degraded Emerald green-containing layers. Analytical data from four paint cross sections strongly suggest that Emerald green reacts with free fatty acids derived from the binding medium forming copper soaps and mobile arsenic-based species. Chemical laboratory experiments fully support this hypothesis. Emerald green and palmitic acid in chloroform form copper palmitate and arsenic trioxide (arsenolite, cubic) under room temperature and normal light conditions. The degradation of Emerald green particles in Descente des vaches has resulted in a loss of light-reflecting surfaces and in newly formed compounds in the paint, both contribute to the colour change from green to brown. 相似文献
4.
Sarah-Jane Fox Caroline Babington Fiona Macalister Thomas Bower Charlotte Martin de Fonjaudran 《文物保护研究》2018,63(5):81-86
ABSTRACTResearch into dust deposition rates on the wall paintings in the State Apartments at the Palace of Westminster, London, UK, began during the restoration of the encaustic floor tiles. The study has broadened to inform day-to-day preventive care for the extensive fine art collections on display and the intricately decorated Gothic interiors, providing a powerful tool for the forthcoming restoration and renewal of the Palace. Different monitoring methods, using optical microscopy, macro-photography and software-based image analysis, were investigated. Qualitative analysis with SEM-EDX and optical microscopy allowed the identification of a number of anthropogenic, geogenic and biological sources of particulate matter, while quantitative results elucidated deposition trends, highlighting both seasonal and works-related impacts. Results indicated that mitigation measures taken to protect works of art and limit the diffusion and deposition of particulate matter on surrounding surfaces were successful. A new dust monitoring method, based on imaging of vertical surfaces and on a recently developed image analysis workflow (CHIJ) operated in open-source software (ImageJ) was trialled alongside more traditional methods for measuring dust deposition through collection of particulate matter on proxies. Results showed significant discrepancies between data acquired directly on wall painting surfaces as compared to horizontal glass slides. The advantages, limitations and complementarity of both monitoring methods were identified, and their potential contributions to the development of data-driven conservation approaches for heritage sites were assessed. The relatively low-tech methods and equipment used present useful and adapted tools for collection managers and conservators to inform their decision-making processes. 相似文献
5.
ABSTRACTComputational social science has caused a shift of research paradigm in social science in general and communication in particular. The special issue brings together a community of active researchers to introduce computational social science for Asia-Pacific communication research. The special issue outlines major computational methods closely related to communication research and demonstrates how computational methods can be applied to address theoretical and practical questions in Asia-Pacific societies. The advantages and limitations of computational methods have been conceptually discussed and/or empirically illustrated. Finally, the special issue provides a guideline of conducting computational research for communication researchers in Asia-Pacific societies and beyond. 相似文献
6.
《The Reference Librarian》2013,54(79-80):343-362
Summary Despite intensive development of computer-based surveillance (CBS), there has been little work on models of such systems. This paper describes a computational model of CBS-output, inputs, and algorithms required to create the output from the inputs. Starting from an assumed requirement that an ideal CBS system be capable of mitigating a bioterroristic outbreak of inhalational Anthrax, the author shows that an output of CBS should be a continuously updated probabilistic threat assessment, which is used to trigger response actions at levels of threat determined by cost-benefit analyses. The paper considers the types of algorithmic transformations required to map from a full spectrum of types of input data to the required output. The set of input data is much broader than previously considered. The specific complementary relationship between the computational model and the evolving architectural model of the National Electronic Disease Surveillance System is discussed. 相似文献
7.
《文物保护研究》2013,58(3):153-155
AbstractThe use of human saliva to clean dirty surfaces has been an intuitive practice for many generations. The authors have established the scientific basis for this practice by means of qualitative tests and chromatographic techniques. α-amylasewas found to be the main constituent responsible for the cleaning power of saliva and therefore amylasic preparations obtained from bread or from microorganisms were tested as saliva substitutes. 相似文献
8.
《文物保护研究》2013,58(4):178-186
AbstractA radioactive tracer has been used to monitor the deposition of lime, that occurs when friable limestone is treated with a lime poultice and multiple applications of limewater. It has been shown that more than half the lime deposited is in the outer 2mm of the stone. Further into the stone, the amount deposited is so small that no consolidating effect can reasonably be expected. 相似文献
9.
ABSTRACT Studies on information and media literacy focus on describing activities and frameworks individually, and most of the time, connect within the field of library science. However, other frameworks and practices can be used. This case study presents the application of Behrman’s Critical Literacy Practices to information and media literacy to engage students to think critically about information within their field of study. The purpose of this research is to model the information behavior of education students through the perspective of constructivist learning. The study used a qualitative method with six upper-level undergraduate education majors. Activities that comprise practices and theories in both education and library sciences are presented to form a continuous exposure to critical thinking. Factors that influenced how students perceived the validity of information came from personal, educational, and societal factors. This research contributes to the ongoing discussion about critical thinking skills in undergraduate students, presenting a model that describes how practices from other fields can be used and incorporated with information and media literacy. 相似文献
10.
Anna Henningsson 《文物保护研究》2018,63(5):113-120
ABSTRACTDuring construction of a 6 km long railway tunnel close to historic churches in Stockholm, a preventive monitoring model was applied for ensembles of large-scale immovable ecclesiastical artworks. Construction work such as blasting and pile-driving took place during five years under or very close to these immovable works of art. In Sweden, risk assessment related to construction work is focused on risks associated with the building; meanwhile, there is no common approach for protecting the immovable historic works of art and architectural surfaces. This paper discusses how a preventive model for vibration monitoring on immovable artworks was developed and used as well as how the preventive purpose was perceived by different stakeholders during and after the tunnelling work. Experience from this project concludes that monitoring that includes uniform visual inspection becomes crucial for being able to protect the artworks. The concept of vibrations standards relying on fixed numbers of critical vibrations levels for mitigating the effects of vibration on immovable art can be questioned based on experiences from this project. 相似文献
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12.
Marisa L. Conte Mark P. MacEachern Nandita S. Mani Whitney A. Townsend Judith E. Smith Chase Masters Caitlin Kelley 《Journal of the Medical Library Association》2015,103(2):69-73
Objective:The researchers used the flipped classroom model to develop and conduct a systematic review course for librarians.Setting:The research took place at an academic health sciences library.Method:A team of informationists developed and conducted a pilot course. Assessment informed changes to both course components; a second course addressed gaps in the pilot.Conclusion:The flipped classroom model can be successful in developing and implementing a course that is well rated by students. 相似文献
13.
Pawel Popiel 《广播与电子媒介杂志》2020,64(2):341-364
ABSTRACT The content of political communication of independent regulatory agencies (IRAs) is understudied. Combining computational text analysis and qualitative document analysis, this study analyzes over 7,500 speeches and statements of Federal Communications Commission (FCC) commissioners, given over two decades, to examine how political and industry influence on policymaking manifest themselves discursively. The results shed light on how external factors, such as regulator party affiliation and passage through the revolving door, exert influence on IRAs by impacting agenda-setting processes and occasionally the content of regulators’ political communication. However, the findings also reveal the contingency of this influence in selected contexts as well. 相似文献
14.
《文物保护研究》2013,58(4):264-272
AbstractThe removal of calcareous accretions from archaeological bronzes can be a difficult step in their conservation. Chemical cleaning with chelating agents might be an alternative to mechanical methods. In this study the use of the chelating agent sodium tripolyphosphate (STPP) was examined to determine whether it is effective in discriminating between calcium carbonate and copper patina, and non-corrosive to copper alloys in the presence of air. Comparative experiments with STPP and disodium ethylenediamine-tetraacetate (Na2-EDTA) were carried out on synthetic malachite, cuprite, calcium carbonate, naturally polished malachite surfaces and sheets of bronze and brass. In addition to the properties of the chelating agent, the solubility of the salts and the pH values of the solutions are crucial factors in the removal of compounds of low solubility. The quantity of metal ions dissolved, estimated by atomic absorption spectral analysis and scanning electron microscopy, showed that the calcareous accretions could be removed satisfactorily, but STPP also dissolved constituent parts of the patina, such as malachite and cuprite, and may harm bronze or brass. Compared to Na2-EDTA, STPP is less effective in dissolving calcium carbonate. It is less harmful to the patina and base metal, but may lead to patination of the underlying metal. 相似文献
15.
ABSTRACTPublic librarians face various factors that can affect professional practice: socio-cultural nuances of diverse information needs, isolation due to system-wide location and/or geography, and systemic disconnection from professional networking and learning opportunities. To address these factors, an inquiry-based professional development model called The Librarians’ Inquiry Forum (LINQ) was devised and employed with a select group of Hawai’i-based public librarians via the cloud-based collaborative workspace platform, Slack, as a means of building a community-of-practice for professional learning and development. This article reports the evolution and early implementation of the LINQ model. Inquiry-based research often reveals data that raises more questions than answers. Questions raised from the reflective research performed with LINQ revealed ways in which the LINQ librarians learned “better” ways/approaches of practice. LINQ was found to be a viable method for enhancing public librarian professional development. 相似文献
16.
ABSTRACTSticky rice paste is a viscous material commonly used in traditional Chinese construction. It has the basic properties of high viscosity and viscoelasticity, good corrosion and weather resistance, and a small coefficient of expansion. Sticky rice paste is usually added to site soils to modify their basic physical and mechanical properties. This study found that gelatinized sticky rice-paste-modified site soils have clearly improved physical and mechanical properties compared to 20 and 100°C water-modified soils when 1% (wt%) sticky rice paste is added as the soil modifier. The liquid and plastic limits, and the plastic index of the soil are improved upon modification, to 27.4, 17.7, and 9.7%, respectively. The unconfined compressive strength and hydraulic conductivity were significantly increased and reduced, respectively. In addition, there was a reduction in the rate of disintegration by water, while the water resistance of the soil was improved. X-ray diffraction, Fourier transform infrared, and thermogravimetry/differential scanning calorimetry studies reveal that the improved properties arise through physical processes between the sticky rice paste and the soil. Scanning electron microscopy reveals that dispersed branched-chain sticky rice-paste molecules extensively infiltrate the surfaces of the soil particles on the nanoscale and become attached to them to form a good adhesive colloid that solidifies the soil particles after water evaporation, resulting in a compact structure. 相似文献
17.
Rebecca Knuth 《International Information and Library Review》2013,45(2):77-89
AbstractPublic and school library development has been slow in Third World countries. This can only be overcome by a shift in perception whereby libraries become important to national development and educational and literacy goals. When considering transformation in library mission and delivery systems, combined school and public libraries offer an alternate and innovative model. Research has determined conditions under which combined libraries are successful and when these success factors and conditions in developing countries are juxtaposed, striking correlations appear. Combined libraries may offer the integration necessary in a climate of scarcity; they may provide the framework in which libraries can serve all the people by contributing to a literate environment and literacy efforts, while supporting formal education and development programs. 相似文献
18.
《图书馆管理杂志》2013,53(1-2):263-324
SUMMARY The quantity of legal and government information accessible through online delivery has increased tremendously. Information technology has revolutionized the way much of this information is disseminated by government and the way that researchers access it. The increase in publication can be attributed to two factors: the government's efforts to create a virtual depository of publications and the capability of Internet technology to provide personalized “feeds” of topic-specific information through Web logs and RSS news aggregators. In this article, finding tools, primary and secondary sources of legal and regulatory government information will be identified and described including search engines and guides. 相似文献
19.
Matthew S. Weber 《Communication methods and measures》2018,12(2-3):200-215
ABSTRACTThis article examines the role of web archives as a critical source of data for conducting computational communication research. Web archives are large-scale databases containing comprehensive records of websites showing how those websites have evolved over time. Recent communication scholarship using web archives is reviewed, demonstrating the breadth of research conducted in this space. Subsequently, a methodological framework is proposed for using web archives in computational communication research. As a source of data, web archives present a number of methodological challenges, particularly with regards to the accuracy and completeness of web archives. These problems are addressed in order to better inform future work in this area. The closing sections outline a forward-looking trajectory for computational communication research using web archives. 相似文献