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Elena Crespi Antonio Capolongo Davide Fissore Antonello A. Barresi 《Drying Technology》2008,26(3):349-356
The aim of this article is to develop an experiment and a procedure to investigate the restoration of water-damaged paper and archival materials using freeze drying in order to allow a reproducible test and comparison of the influence of different operating conditions on drying time and restored paper quality. Firstly, a reproducible method for the preparation of soaked samples simulating water-damaged paper has been developed. Then, the samples have been freeze-dried in a laboratory-scale apparatus that allowed monitoring the temperature as well as the weight of the samples. The technique of evaporative freezing, which reduces the drying time required, has been used in this case. An innovative procedure for the visualization of the progress of the drying process has been validated, thus allowing the validation of a simple phenomenological model of the time evolution of the ice core volume; in addition, data on the residual moisture of the dried paper sheets in different zones have been given. Finally, optimization of this particular drying process by using simple or more sophisticated approaches has been discussed. 相似文献
33.
Imperfection in information can be considered a crosscutting concern that manifests itself in diverse kinds of imprecision, uncertainty, or inconsistency in the data models of a software system. The extension of existing programming and querying interfaces for the different aspects of information imperfection requires a proper modularization of the different concerns of numerical imprecision handling, so that the extensions do not interfere with existing programming practices and do not obscure the original design. Aspect‐oriented design (AOD) enables such a form of nonintrusive extensions to be added to existing software libraries, clearly separating fuzziness or other imperfections in data as a differentiated concern that can be considered from the early phases of development. In this article, a general framework for aspect‐based extension of data models and fuzzy databases is described, and some design and implementation issues of such AOD‐based extensions on OJB database libraries are described as a case study. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 1199–1216, 2006. 相似文献
34.
Designing Templates for Mining Association Rules 总被引:3,自引:0,他引:3
Current approaches to data mining usually address specific userrequests, while no general design criteria for the extraction of associationrules are available for the end-user. In this paper, we propose aclassification of association rule types, which provides a general frameworkfor the design of association rule mining applications. Based on theidentified association rule types, we introduce predefined templates as ameans to capture the user specification of mining applications. Furthermore,we propose a general language to design templates for the extraction ofarbitrary association rule types. 相似文献
35.
M. Ardizzi N. Ballarini F. Cavani E. Chiappini L. Dal Pozzo L. Maselli T. Monti 《Applied catalysis. B, Environmental》2007,70(1-4):597-605
The properties of catalysts with (i) Brønsted-type acidity (H-mordenite and Al/P mixed oxide), (ii) Lewis-type acidity (Al trifluoride) or (iii) basic characteristics (Mg/Fe mixed oxide) were investigated in the gas-phase methylation of catechol. When methanol was used as the methylating agent, H-mordenite and AlF3 gave high selectivities to guaiacol (the product of O-methylation) under mild reaction conditions, that is at very low catechol conversions. An increase in temperature led to the transformation of guaiacol to phenol and cresols, and to considerable catalyst deactivation. The basic catalyst Mg/Fe/O also favored an extensive degradation of guaiacol to phenol. On the mildly acidic catalyst Al/P mixed oxide a stable catalytic performance and a high selectivity to guaiacol at 40% catechol conversion were obtained. When methylformate, a more reactive methylating agent, was used with AlF3 and Mg/Fe mixed oxide as catalysts, higher catechol conversions and slower deactivation rates could be achieved under mild reaction conditions, with a low extent of guaiacol degradation. However, methylformate rapidly decomposed when temperatures above 350 °C were used. Finally, tests were made by reacting catechol and diethoxymethane with acid catalysts, with the aim of synthesizing methylenedioxybenzene. The latter product was obtained with high selectivity, but with very low yield, due to both catalyst deactivation and decomposition of diethoxymethane. 相似文献
36.
This article evaluatively reviews the literature on dynamic testing, a collection of testing procedures designed to quantify not only the products or even the processes of learning but also the potential to learn. The article considers a variety of approaches to dynamic testing and the strengths and weaknesses of each. Moreover, the literature on each approach is reviewed and analyzed in terms of the extent to which it fulfills the claims made for it. In all of these approaches, testing involves learning at the time of test, rather than just static testing of what has been learned before. It is concluded that dynamic testing has great potential for helping to understand people's potentials but that its potential has yet to be realized fully. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
We consider the potential impact of Computer Supported Cooperative Work, with special reference to large technically advanced projects involving several organizations. It is vital that such projects are managed efficiently, without delays, since a product that reaches the market a few months earlier than its competitors enjoys a great advantage. Traditional methods of coordinating large projects, based on hierarchical communication, tend to produce delays, since technicians at remote sites are obliged to solve coordination problems by passing them up the hierachy. It would be better if such problems were solved by improvising conferences among the technicians; Computer Supported Cooperative Work will provide the technical means of implementing this heterarchical style of management without losing control of the project. The use of computers as a social medium raises methodological and ethical issues which are discussed in the final section. 相似文献
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Hobbie KA Peterson ES Barton ML Waters KM Anderson KA 《Journal of laboratory automation》2012,17(4):275-283
Large collaborative centers are a common model for accomplishing integrated environmental health research. These centers often include various types of scientific domains (e.g., chemistry, biology, bioinformatics) that are integrated to solve some of the nation's key economic or public health concerns. The Superfund Research Center (SRP) at Oregon State University (OSU) is one such center established in 2008 to study the emerging health risks of polycyclic aromatic hydrocarbons while using new technologies both in the field and laboratory. With outside collaboration at remote institutions, success for the center as a whole depends on the ability to effectively integrate data across all research projects and support cores. Therefore, the OSU SRP center developed a system that integrates environmental monitoring data with analytical chemistry data and downstream bioinformatics and statistics to enable complete "source-to-outcome" data modeling and information management. This article describes the development of this integrated information management system that includes commercial software for operational laboratory management and sample management in addition to open-source custom-built software for bioinformatics and experimental data management. 相似文献